fs/smb/client/dir.c

   1 // SPDX-License-Identifier: LGPL-2.1
   2 /*
   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  */
  10 #include <linux/fs.h>
  11 #include <linux/stat.h>
  12 #include <linux/slab.h>
  13 #include <linux/namei.h>
  14 #include <linux/mount.h>
  15 #include <linux/file.h>
  16 #include "cifsfs.h"
  17 #include "cifspdu.h"
  18 #include "cifsglob.h"
  19 #include "cifsproto.h"
  20 #include "cifs_debug.h"
  21 #include "cifs_fs_sb.h"
  22 #include "cifs_unicode.h"
  23 #include "fs_context.h"
  24 #include "cifs_ioctl.h"
  25 #include "fscache.h"
  26
  27 static void
  28 renew_parental_timestamps(struct dentry *direntry)
  29 {
  30         /* BB check if there is a way to get the kernel to do this or if we
  31            really need this */
  32         do {
  33                 cifs_set_time(direntry, jiffies);
  34                 direntry = direntry->d_parent;
  35         } while (!IS_ROOT(direntry));
  36 }
  37
  38 char *
  39 cifs_build_path_to_root(struct smb3_fs_context *ctx, struct cifs_sb_info *cifs_sb,
  40                         struct cifs_tcon *tcon, int add_treename)
  41 {
  42         int pplen = ctx->prepath ? strlen(ctx->prepath) + 1 : 0;
  43         int dfsplen;
  44         char *full_path = NULL;
  45
  46         /* if no prefix path, simply set path to the root of share to "" */
  47         if (pplen == 0) {
  48                 full_path = kzalloc(1, GFP_KERNEL);
  49                 return full_path;
  50         }
  51
  52         if (add_treename)
  53                 dfsplen = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1);
  54         else
  55                 dfsplen = 0;
  56
  57         full_path = kmalloc(dfsplen + pplen + 1, GFP_KERNEL);
  58         if (full_path == NULL)
  59                 return full_path;
  60
  61         if (dfsplen)
  62                 memcpy(full_path, tcon->tree_name, dfsplen);
  63         full_path[dfsplen] = CIFS_DIR_SEP(cifs_sb);
  64         memcpy(full_path + dfsplen + 1, ctx->prepath, pplen);
  65         convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
  66         return full_path;
  67 }
  68
  69 /* Note: caller must free return buffer */
  70 const char *
  71 build_path_from_dentry(struct dentry *direntry, void *page)
  72 {
  73         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
  74         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
  75         bool prefix = tcon->Flags & SMB_SHARE_IS_IN_DFS;
  76
  77         return build_path_from_dentry_optional_prefix(direntry, page,
  78                                                       prefix);
  79 }
  80
  81 char *__build_path_from_dentry_optional_prefix(struct dentry *direntry, void *page,
  82                                                const char *tree, int tree_len,
  83                                                bool prefix)
  84 {
  85         int dfsplen;
  86         int pplen = 0;
  87         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
  88         char dirsep = CIFS_DIR_SEP(cifs_sb);
  89         char *s;
  90
  91         if (unlikely(!page))
  92                 return ERR_PTR(-ENOMEM);
  93
  94         if (prefix)
  95                 dfsplen = strnlen(tree, tree_len + 1);
  96         else
  97                 dfsplen = 0;
  98
  99         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH)
 100                 pplen = cifs_sb->prepath ? strlen(cifs_sb->prepath) + 1 : 0;
 101
 102         s = dentry_path_raw(direntry, page, PATH_MAX);
 103         if (IS_ERR(s))
 104                 return s;
 105         if (!s[1])      // for root we want "", not "/"
 106                 s++;
 107         if (s < (char *)page + pplen + dfsplen)
 108                 return ERR_PTR(-ENAMETOOLONG);
 109         if (pplen) {
 110                 cifs_dbg(FYI, "using cifs_sb prepath <%s>\n", cifs_sb->prepath);
 111                 s -= pplen;
 112                 memcpy(s + 1, cifs_sb->prepath, pplen - 1);
 113                 *s = '/';
 114         }
 115         if (dirsep != '/') {
 116                 /* BB test paths to Windows with '/' in the midst of prepath */
 117                 char *p;
 118
 119                 for (p = s; *p; p++)
 120                         if (*p == '/')
 121                                 *p = dirsep;
 122         }
 123         if (dfsplen) {
 124                 s -= dfsplen;
 125                 memcpy(s, tree, dfsplen);
 126                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {
 127                         int i;
 128                         for (i = 0; i < dfsplen; i++) {
 129                                 if (s[i] == '\\')
 130                                         s[i] = '/';
 131                         }
 132                 }
 133         }
 134         return s;
 135 }
 136
 137 char *build_path_from_dentry_optional_prefix(struct dentry *direntry, void *page,
 138                                              bool prefix)
 139 {
 140         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 141         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
 142
 143         return __build_path_from_dentry_optional_prefix(direntry, page, tcon->tree_name,
 144                                                         MAX_TREE_SIZE, prefix);
 145 }
 146
 147 /*
 148  * Don't allow path components longer than the server max.
 149  * Don't allow the separator character in a path component.
 150  * The VFS will not allow "/", but "\" is allowed by posix.
 151  */
 152 static int
 153 check_name(struct dentry *direntry, struct cifs_tcon *tcon)
 154 {
 155         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 156         int i;
 157
 158         if (unlikely(tcon->fsAttrInfo.MaxPathNameComponentLength &&
 159                      direntry->d_name.len >
 160                      le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength)))
 161                 return -ENAMETOOLONG;
 162
 163         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
 164                 for (i = 0; i < direntry->d_name.len; i++) {
 165                         if (direntry->d_name.name[i] == '\\') {
 166                                 cifs_dbg(FYI, "Invalid file name\n");
 167                                 return -EINVAL;
 168                         }
 169                 }
 170         }
 171         return 0;
 172 }
 173
 174
 175 /* Inode operations in similar order to how they appear in Linux file fs.h */
 176
 177 static int cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
 178                           struct tcon_link *tlink, unsigned int oflags, umode_t mode, __u32 *oplock,
 179                           struct cifs_fid *fid, struct cifs_open_info_data *buf)
 180 {
 181         int rc = -ENOENT;
 182         int create_options = CREATE_NOT_DIR;
 183         int desired_access;
 184         struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
 185         struct cifs_tcon *tcon = tlink_tcon(tlink);
 186         const char *full_path;
 187         void *page = alloc_dentry_path();
 188         struct inode *newinode = NULL;
 189         int disposition;
 190         struct TCP_Server_Info *server = tcon->ses->server;
 191         struct cifs_open_parms oparms;
 192         int rdwr_for_fscache = 0;
 193
 194         *oplock = 0;
 195         if (tcon->ses->server->oplocks)
 196                 *oplock = REQ_OPLOCK;
 197
 198         full_path = build_path_from_dentry(direntry, page);
 199         if (IS_ERR(full_path)) {
 200                 free_dentry_path(page);
 201                 return PTR_ERR(full_path);
 202         }
 203
 204         /* If we're caching, we need to be able to fill in around partial writes. */
 205         if (cifs_fscache_enabled(inode) && (oflags & O_ACCMODE) == O_WRONLY)
 206                 rdwr_for_fscache = 1;
 207
 208 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
 209         if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
 210             (CIFS_UNIX_POSIX_PATH_OPS_CAP &
 211                         le64_to_cpu(tcon->fsUnixInfo.Capability))) {
 212                 rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
 213                                      oflags, oplock, &fid->netfid, xid);
 214                 switch (rc) {
 215                 case 0:
 216                         if (newinode == NULL) {
 217                                 /* query inode info */
 218                                 goto cifs_create_get_file_info;
 219                         }
 220
 221                         if (S_ISDIR(newinode->i_mode)) {
 222                                 CIFSSMBClose(xid, tcon, fid->netfid);
 223                                 iput(newinode);
 224                                 rc = -EISDIR;
 225                                 goto out;
 226                         }
 227
 228                         if (!S_ISREG(newinode->i_mode)) {
 229                                 /*
 230                                  * The server may allow us to open things like
 231                                  * FIFOs, but the client isn't set up to deal
 232                                  * with that. If it's not a regular file, just
 233                                  * close it and proceed as if it were a normal
 234                                  * lookup.
 235                                  */
 236                                 CIFSSMBClose(xid, tcon, fid->netfid);
 237                                 goto cifs_create_get_file_info;
 238                         }
 239                         /* success, no need to query */
 240                         goto cifs_create_set_dentry;
 241
 242                 case -ENOENT:
 243                         goto cifs_create_get_file_info;
 244
 245                 case -EIO:
 246                 case -EINVAL:
 247                         /*
 248                          * EIO could indicate that (posix open) operation is not
 249                          * supported, despite what server claimed in capability
 250                          * negotiation.
 251                          *
 252                          * POSIX open in samba versions 3.3.1 and earlier could
 253                          * incorrectly fail with invalid parameter.
 254                          */
 255                         tcon->broken_posix_open = true;
 256                         break;
 257
 258                 case -EREMOTE:
 259                 case -EOPNOTSUPP:
 260                         /*
 261                          * EREMOTE indicates DFS junction, which is not handled
 262                          * in posix open.  If either that or op not supported
 263                          * returned, follow the normal lookup.
 264                          */
 265                         break;
 266
 267                 default:
 268                         goto out;
 269                 }
 270                 /*
 271                  * fallthrough to retry, using older open call, this is case
 272                  * where server does not support this SMB level, and falsely
 273                  * claims capability (also get here for DFS case which should be
 274                  * rare for path not covered on files)
 275                  */
 276         }
 277 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
 278
 279         desired_access = 0;
 280         if (OPEN_FMODE(oflags) & FMODE_READ)
 281                 desired_access |= GENERIC_READ; /* is this too little? */
 282         if (OPEN_FMODE(oflags) & FMODE_WRITE)
 283                 desired_access |= GENERIC_WRITE;
 284         if (rdwr_for_fscache == 1)
 285                 desired_access |= GENERIC_READ;
 286
 287         disposition = FILE_OVERWRITE_IF;
 288         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 289                 disposition = FILE_CREATE;
 290         else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
 291                 disposition = FILE_OVERWRITE_IF;
 292         else if ((oflags & O_CREAT) == O_CREAT)
 293                 disposition = FILE_OPEN_IF;
 294         else
 295                 cifs_dbg(FYI, "Create flag not set in create function\n");
 296
 297         /*
 298          * BB add processing to set equivalent of mode - e.g. via CreateX with
 299          * ACLs
 300          */
 301
 302         if (!server->ops->open) {
 303                 rc = -ENOSYS;
 304                 goto out;
 305         }
 306
 307         /*
 308          * if we're not using unix extensions, see if we need to set
 309          * ATTR_READONLY on the create call
 310          */
 311         if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
 312                 create_options |= CREATE_OPTION_READONLY;
 313
 314 retry_open:
 315         oparms = (struct cifs_open_parms) {
 316                 .tcon = tcon,
 317                 .cifs_sb = cifs_sb,
 318                 .desired_access = desired_access,
 319                 .create_options = cifs_create_options(cifs_sb, create_options),
 320                 .disposition = disposition,
 321                 .path = full_path,
 322                 .fid = fid,
 323                 .mode = mode,
 324         };
 325         rc = server->ops->open(xid, &oparms, oplock, buf);
 326         if (rc) {
 327                 cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);
 328                 if (rc == -EACCES && rdwr_for_fscache == 1) {
 329                         desired_access &= ~GENERIC_READ;
 330                         rdwr_for_fscache = 2;
 331                         goto retry_open;
 332                 }
 333                 goto out;
 334         }
 335         if (rdwr_for_fscache == 2)
 336                 cifs_invalidate_cache(inode, FSCACHE_INVAL_DIO_WRITE);
 337
 338 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
 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
 374 cifs_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 #else
 381         {
 382 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
 383                 /* TODO: Add support for calling POSIX query info here, but passing in fid */
 384                 rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb, xid, fid);
 385                 if (newinode) {
 386                         if (server->ops->set_lease_key)
 387                                 server->ops->set_lease_key(newinode, fid);
 388                         if ((*oplock & CIFS_CREATE_ACTION) && S_ISREG(newinode->i_mode)) {
 389                                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
 390                                         newinode->i_mode = mode;
 391                                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 392                                         newinode->i_uid = current_fsuid();
 393                                         if (inode->i_mode & S_ISGID)
 394                                                 newinode->i_gid = inode->i_gid;
 395                                         else
 396                                                 newinode->i_gid = current_fsgid();
 397                                 }
 398                         }
 399                 }
 400         }
 401
 402 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
 403 cifs_create_set_dentry:
 404 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
 405         if (rc != 0) {
 406                 cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",
 407                          rc);
 408                 goto out_err;
 409         }
 410
 411         if (newinode)
 412                 if (S_ISDIR(newinode->i_mode)) {
 413                         rc = -EISDIR;
 414                         goto out_err;
 415                 }
 416
 417         d_drop(direntry);
 418         d_add(direntry, newinode);
 419
 420 out:
 421         free_dentry_path(page);
 422         return rc;
 423
 424 out_err:
 425         if (server->ops->close)
 426                 server->ops->close(xid, tcon, fid);
 427         if (newinode)
 428                 iput(newinode);
 429         goto out;
 430 }
 431
 432 int
 433 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 434                  struct file *file, unsigned oflags, umode_t mode)
 435 {
 436         int rc;
 437         unsigned int xid;
 438         struct tcon_link *tlink;
 439         struct cifs_tcon *tcon;
 440         struct TCP_Server_Info *server;
 441         struct cifs_fid fid = {};
 442         struct cifs_pending_open open;
 443         __u32 oplock;
 444         struct cifsFileInfo *file_info;
 445         struct cifs_open_info_data buf = {};
 446
 447         if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb))))
 448                 return -EIO;
 449
 450         /*
 451          * Posix open is only called (at lookup time) for file create now. For
 452          * opens (rather than creates), because we do not know if it is a file
 453          * or directory yet, and current Samba no longer allows us to do posix
 454          * open on dirs, we could end up wasting an open call on what turns out
 455          * to be a dir. For file opens, we wait to call posix open till
 456          * cifs_open.  It could be added to atomic_open in the future but the
 457          * performance tradeoff of the extra network request when EISDIR or
 458          * EACCES is returned would have to be weighed against the 50% reduction
 459          * in network traffic in the other paths.
 460          */
 461         if (!(oflags & O_CREAT)) {
 462                 struct dentry *res;
 463
 464                 /*
 465                  * Check for hashed negative dentry. We have already revalidated
 466                  * the dentry and it is fine. No need to perform another lookup.
 467                  */
 468                 if (!d_in_lookup(direntry))
 469                         return -ENOENT;
 470
 471                 res = cifs_lookup(inode, direntry, 0);
 472                 if (IS_ERR(res))
 473                         return PTR_ERR(res);
 474
 475                 return finish_no_open(file, res);
 476         }
 477
 478         xid = get_xid();
 479
 480         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 481                  inode, direntry, direntry);
 482
 483         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 484         if (IS_ERR(tlink)) {
 485                 rc = PTR_ERR(tlink);
 486                 goto out_free_xid;
 487         }
 488
 489         tcon = tlink_tcon(tlink);
 490
 491         rc = check_name(direntry, tcon);
 492         if (rc)
 493                 goto out;
 494
 495         server = tcon->ses->server;
 496
 497         if (server->ops->new_lease_key)
 498                 server->ops->new_lease_key(&fid);
 499
 500         cifs_add_pending_open(&fid, tlink, &open);
 501
 502         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 503                             &oplock, &fid, &buf);
 504         if (rc) {
 505                 cifs_del_pending_open(&open);
 506                 goto out;
 507         }
 508
 509         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 510                 file->f_mode |= FMODE_CREATED;
 511
 512         rc = finish_open(file, direntry, generic_file_open);
 513         if (rc) {
 514                 if (server->ops->close)
 515                         server->ops->close(xid, tcon, &fid);
 516                 cifs_del_pending_open(&open);
 517                 goto out;
 518         }
 519
 520         if (file->f_flags & O_DIRECT &&
 521             CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
 522                 if (CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
 523                         file->f_op = &cifs_file_direct_nobrl_ops;
 524                 else
 525                         file->f_op = &cifs_file_direct_ops;
 526                 }
 527
 528         file_info = cifs_new_fileinfo(&fid, file, tlink, oplock, buf.symlink_target);
 529         if (file_info == NULL) {
 530                 if (server->ops->close)
 531                         server->ops->close(xid, tcon, &fid);
 532                 cifs_del_pending_open(&open);
 533                 rc = -ENOMEM;
 534                 goto out;
 535         }
 536
 537         fscache_use_cookie(cifs_inode_cookie(file_inode(file)),
 538                            file->f_mode & FMODE_WRITE);
 539
 540 out:
 541         cifs_put_tlink(tlink);
 542 out_free_xid:
 543         free_xid(xid);
 544         cifs_free_open_info(&buf);
 545         return rc;
 546 }
 547
 548 int cifs_create(struct mnt_idmap *idmap, struct inode *inode,
 549                 struct dentry *direntry, umode_t mode, bool excl)
 550 {
 551         int rc;
 552         unsigned int xid = get_xid();
 553         /*
 554          * BB below access is probably too much for mknod to request
 555          *    but we have to do query and setpathinfo so requesting
 556          *    less could fail (unless we want to request getatr and setatr
 557          *    permissions (only).  At least for POSIX we do not have to
 558          *    request so much.
 559          */
 560         unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
 561         struct tcon_link *tlink;
 562         struct cifs_tcon *tcon;
 563         struct TCP_Server_Info *server;
 564         struct cifs_fid fid;
 565         __u32 oplock;
 566         struct cifs_open_info_data buf = {};
 567
 568         cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 569                  inode, direntry, direntry);
 570
 571         if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb)))) {
 572                 rc = -EIO;
 573                 goto out_free_xid;
 574         }
 575
 576         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 577         rc = PTR_ERR(tlink);
 578         if (IS_ERR(tlink))
 579                 goto out_free_xid;
 580
 581         tcon = tlink_tcon(tlink);
 582         server = tcon->ses->server;
 583
 584         if (server->ops->new_lease_key)
 585                 server->ops->new_lease_key(&fid);
 586
 587         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode, &oplock, &fid, &buf);
 588         if (!rc && server->ops->close)
 589                 server->ops->close(xid, tcon, &fid);
 590
 591         cifs_free_open_info(&buf);
 592         cifs_put_tlink(tlink);
 593 out_free_xid:
 594         free_xid(xid);
 595         return rc;
 596 }
 597
 598 int cifs_mknod(struct mnt_idmap *idmap, struct inode *inode,
 599                struct dentry *direntry, umode_t mode, dev_t device_number)
 600 {
 601         int rc = -EPERM;
 602         unsigned int xid;
 603         struct cifs_sb_info *cifs_sb;
 604         struct tcon_link *tlink;
 605         struct cifs_tcon *tcon;
 606         const char *full_path;
 607         void *page;
 608
 609         if (!old_valid_dev(device_number))
 610                 return -EINVAL;
 611
 612         cifs_sb = CIFS_SB(inode->i_sb);
 613         if (unlikely(cifs_forced_shutdown(cifs_sb)))
 614                 return -EIO;
 615
 616         tlink = cifs_sb_tlink(cifs_sb);
 617         if (IS_ERR(tlink))
 618                 return PTR_ERR(tlink);
 619
 620         page = alloc_dentry_path();
 621         tcon = tlink_tcon(tlink);
 622         xid = get_xid();
 623
 624         full_path = build_path_from_dentry(direntry, page);
 625         if (IS_ERR(full_path)) {
 626                 rc = PTR_ERR(full_path);
 627                 goto mknod_out;
 628         }
 629
 630         rc = tcon->ses->server->ops->make_node(xid, inode, direntry, tcon,
 631                                                full_path, mode,
 632                                                device_number);
 633
 634 mknod_out:
 635         free_dentry_path(page);
 636         free_xid(xid);
 637         cifs_put_tlink(tlink);
 638         return rc;
 639 }
 640
 641 struct dentry *
 642 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 643             unsigned int flags)
 644 {
 645         unsigned int xid;
 646         int rc = 0; /* to get around spurious gcc warning, set to zero here */
 647         struct cifs_sb_info *cifs_sb;
 648         struct tcon_link *tlink;
 649         struct cifs_tcon *pTcon;
 650         struct inode *newInode = NULL;
 651         const char *full_path;
 652         void *page;
 653         int retry_count = 0;
 654
 655         xid = get_xid();
 656
 657         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 658                  parent_dir_inode, direntry, direntry);
 659
 660         /* check whether path exists */
 661
 662         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
 663         tlink = cifs_sb_tlink(cifs_sb);
 664         if (IS_ERR(tlink)) {
 665                 free_xid(xid);
 666                 return ERR_CAST(tlink);
 667         }
 668         pTcon = tlink_tcon(tlink);
 669
 670         rc = check_name(direntry, pTcon);
 671         if (unlikely(rc)) {
 672                 cifs_put_tlink(tlink);
 673                 free_xid(xid);
 674                 return ERR_PTR(rc);
 675         }
 676
 677         /* can not grab the rename sem here since it would
 678         deadlock in the cases (beginning of sys_rename itself)
 679         in which we already have the sb rename sem */
 680         page = alloc_dentry_path();
 681         full_path = build_path_from_dentry(direntry, page);
 682         if (IS_ERR(full_path)) {
 683                 cifs_put_tlink(tlink);
 684                 free_xid(xid);
 685                 free_dentry_path(page);
 686                 return ERR_CAST(full_path);
 687         }
 688
 689         if (d_really_is_positive(direntry)) {
 690                 cifs_dbg(FYI, "non-NULL inode in lookup\n");
 691         } else {
 692                 cifs_dbg(FYI, "NULL inode in lookup\n");
 693         }
 694         cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
 695                  full_path, d_inode(direntry));
 696
 697 again:
 698         if (pTcon->posix_extensions) {
 699                 rc = smb311_posix_get_inode_info(&newInode, full_path, NULL,
 700                                                  parent_dir_inode->i_sb, xid);
 701         } else if (pTcon->unix_ext) {
 702                 rc = cifs_get_inode_info_unix(&newInode, full_path,
 703                                               parent_dir_inode->i_sb, xid);
 704         } else {
 705                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
 706                                 parent_dir_inode->i_sb, xid, NULL);
 707         }
 708
 709         if (rc == 0) {
 710                 /* since paths are not looked up by component - the parent
 711                    directories are presumed to be good here */
 712                 renew_parental_timestamps(direntry);
 713         } else if (rc == -EAGAIN && retry_count++ < 10) {
 714                 goto again;
 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         free_dentry_path(page);
 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         int rc;
 737
 738         if (flags & LOOKUP_RCU)
 739                 return -ECHILD;
 740
 741         if (d_really_is_positive(direntry)) {
 742                 inode = d_inode(direntry);
 743                 if ((flags & LOOKUP_REVAL) && !CIFS_CACHE_READ(CIFS_I(inode)))
 744                         CIFS_I(inode)->time = 0; /* force reval */
 745
 746                 rc = cifs_revalidate_dentry(direntry);
 747                 if (rc) {
 748                         cifs_dbg(FYI, "cifs_revalidate_dentry failed with rc=%d", rc);
 749                         switch (rc) {
 750                         case -ENOENT:
 751                         case -ESTALE:
 752                                 /*
 753                                  * Those errors mean the dentry is invalid
 754                                  * (file was deleted or recreated)
 755                                  */
 756                                 return 0;
 757                         default:
 758                                 /*
 759                                  * Otherwise some unexpected error happened
 760                                  * report it as-is to VFS layer
 761                                  */
 762                                 return rc;
 763                         }
 764                 }
 765                 else {
 766                         /*
 767                          * If the inode wasn't known to be a dfs entry when
 768                          * the dentry was instantiated, such as when created
 769                          * via ->readdir(), it needs to be set now since the
 770                          * attributes will have been updated by
 771                          * cifs_revalidate_dentry().
 772                          */
 773                         if (IS_AUTOMOUNT(inode) &&
 774                            !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
 775                                 spin_lock(&direntry->d_lock);
 776                                 direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
 777                                 spin_unlock(&direntry->d_lock);
 778                         }
 779
 780                         return 1;
 781                 }
 782         }
 783
 784         /*
 785          * This may be nfsd (or something), anyway, we can't see the
 786          * intent of this. So, since this can be for creation, drop it.
 787          */
 788         if (!flags)
 789                 return 0;
 790
 791         /*
 792          * Drop the negative dentry, in order to make sure to use the
 793          * case sensitive name which is specified by user if this is
 794          * for creation.
 795          */
 796         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
 797                 return 0;
 798
 799         if (time_after(jiffies, cifs_get_time(direntry) + HZ) || !lookupCacheEnabled)
 800                 return 0;
 801
 802         return 1;
 803 }
 804
 805 /* static int cifs_d_delete(struct dentry *direntry)
 806 {
 807         int rc = 0;
 808
 809         cifs_dbg(FYI, "In cifs d_delete, name = %pd\n", direntry);
 810
 811         return rc;
 812 }     */
 813
 814 const struct dentry_operations cifs_dentry_ops = {
 815         .d_revalidate = cifs_d_revalidate,
 816         .d_automount = cifs_d_automount,
 817 /* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
 818 };
 819
 820 static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 821 {
 822         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 823         unsigned long hash;
 824         wchar_t c;
 825         int i, charlen;
 826
 827         hash = init_name_hash(dentry);
 828         for (i = 0; i < q->len; i += charlen) {
 829                 charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
 830                 /* error out if we can't convert the character */
 831                 if (unlikely(charlen < 0))
 832                         return charlen;
 833                 hash = partial_name_hash(cifs_toupper(c), hash);
 834         }
 835         q->hash = end_name_hash(hash);
 836
 837         return 0;
 838 }
 839
 840 static int cifs_ci_compare(const struct dentry *dentry,
 841                 unsigned int len, const char *str, const struct qstr *name)
 842 {
 843         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 844         wchar_t c1, c2;
 845         int i, l1, l2;
 846
 847         /*
 848          * We make the assumption here that uppercase characters in the local
 849          * codepage are always the same length as their lowercase counterparts.
 850          *
 851          * If that's ever not the case, then this will fail to match it.
 852          */
 853         if (name->len != len)
 854                 return 1;
 855
 856         for (i = 0; i < len; i += l1) {
 857                 /* Convert characters in both strings to UTF-16. */
 858                 l1 = codepage->char2uni(&str[i], len - i, &c1);
 859                 l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
 860
 861                 /*
 862                  * If we can't convert either character, just declare it to
 863                  * be 1 byte long and compare the original byte.
 864                  */
 865                 if (unlikely(l1 < 0 && l2 < 0)) {
 866                         if (str[i] != name->name[i])
 867                                 return 1;
 868                         l1 = 1;
 869                         continue;
 870                 }
 871
 872                 /*
 873                  * Here, we again ass|u|me that upper/lowercase versions of
 874                  * a character are the same length in the local NLS.
 875                  */
 876                 if (l1 != l2)
 877                         return 1;
 878
 879                 /* Now compare uppercase versions of these characters */
 880                 if (cifs_toupper(c1) != cifs_toupper(c2))
 881                         return 1;
 882         }
 883
 884         return 0;
 885 }
 886
 887 const struct dentry_operations cifs_ci_dentry_ops = {
 888         .d_revalidate = cifs_d_revalidate,
 889         .d_hash = cifs_ci_hash,
 890         .d_compare = cifs_ci_compare,
 891         .d_automount = cifs_d_automount,
 892 };