fs/smb/client/cached_dir.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Functions to handle the cached directory entries
   4  *
   5  *  Copyright (c) 2022, Ronnie Sahlberg <lsahlber@redhat.com>
   6  */
   7
   8 #include <linux/namei.h>
   9 #include "cifsglob.h"
  10 #include "cifsproto.h"
  11 #include "cifs_debug.h"
  12 #include "smb2proto.h"
  13 #include "cached_dir.h"
  14
  15 static struct cached_fid *init_cached_dir(const char *path);
  16 static void free_cached_dir(struct cached_fid *cfid);
  17 static void smb2_close_cached_fid(struct kref *ref);
  18 static void cfids_laundromat_worker(struct work_struct *work);
  19
  20 static struct cached_fid *find_or_create_cached_dir(struct cached_fids *cfids,
  21                                                     const char *path,
  22                                                     bool lookup_only,
  23                                                     __u32 max_cached_dirs)
  24 {
  25         struct cached_fid *cfid;
  26
  27         spin_lock(&cfids->cfid_list_lock);
  28         list_for_each_entry(cfid, &cfids->entries, entry) {
  29                 if (!strcmp(cfid->path, path)) {
  30                         /*
  31                          * If it doesn't have a lease it is either not yet
  32                          * fully cached or it may be in the process of
  33                          * being deleted due to a lease break.
  34                          */
  35                         if (!cfid->has_lease) {
  36                                 spin_unlock(&cfids->cfid_list_lock);
  37                                 return NULL;
  38                         }
  39                         kref_get(&cfid->refcount);
  40                         spin_unlock(&cfids->cfid_list_lock);
  41                         return cfid;
  42                 }
  43         }
  44         if (lookup_only) {
  45                 spin_unlock(&cfids->cfid_list_lock);
  46                 return NULL;
  47         }
  48         if (cfids->num_entries >= max_cached_dirs) {
  49                 spin_unlock(&cfids->cfid_list_lock);
  50                 return NULL;
  51         }
  52         cfid = init_cached_dir(path);
  53         if (cfid == NULL) {
  54                 spin_unlock(&cfids->cfid_list_lock);
  55                 return NULL;
  56         }
  57         cfid->cfids = cfids;
  58         cfids->num_entries++;
  59         list_add(&cfid->entry, &cfids->entries);
  60         cfid->on_list = true;
  61         kref_get(&cfid->refcount);
  62         spin_unlock(&cfids->cfid_list_lock);
  63         return cfid;
  64 }
  65
  66 static struct dentry *
  67 path_to_dentry(struct cifs_sb_info *cifs_sb, const char *path)
  68 {
  69         struct dentry *dentry;
  70         const char *s, *p;
  71         char sep;
  72
  73         sep = CIFS_DIR_SEP(cifs_sb);
  74         dentry = dget(cifs_sb->root);
  75         s = path;
  76
  77         do {
  78                 struct inode *dir = d_inode(dentry);
  79                 struct dentry *child;
  80
  81                 if (!S_ISDIR(dir->i_mode)) {
  82                         dput(dentry);
  83                         dentry = ERR_PTR(-ENOTDIR);
  84                         break;
  85                 }
  86
  87                 /* skip separators */
  88                 while (*s == sep)
  89                         s++;
  90                 if (!*s)
  91                         break;
  92                 p = s++;
  93                 /* next separator */
  94                 while (*s && *s != sep)
  95                         s++;
  96
  97                 child = lookup_positive_unlocked(p, dentry, s - p);
  98                 dput(dentry);
  99                 dentry = child;
 100         } while (!IS_ERR(dentry));
 101         return dentry;
 102 }
 103
 104 static const char *path_no_prefix(struct cifs_sb_info *cifs_sb,
 105                                   const char *path)
 106 {
 107         size_t len = 0;
 108
 109         if (!*path)
 110                 return path;
 111
 112         if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
 113             cifs_sb->prepath) {
 114                 len = strlen(cifs_sb->prepath) + 1;
 115                 if (unlikely(len > strlen(path)))
 116                         return ERR_PTR(-EINVAL);
 117         }
 118         return path + len;
 119 }
 120
 121 /*
 122  * Open the and cache a directory handle.
 123  * If error then *cfid is not initialized.
 124  */
 125 int open_cached_dir(unsigned int xid, struct cifs_tcon *tcon,
 126                     const char *path,
 127                     struct cifs_sb_info *cifs_sb,
 128                     bool lookup_only, struct cached_fid **ret_cfid)
 129 {
 130         struct cifs_ses *ses;
 131         struct TCP_Server_Info *server;
 132         struct cifs_open_parms oparms;
 133         struct smb2_create_rsp *o_rsp = NULL;
 134         struct smb2_query_info_rsp *qi_rsp = NULL;
 135         int resp_buftype[2];
 136         struct smb_rqst rqst[2];
 137         struct kvec rsp_iov[2];
 138         struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
 139         struct kvec qi_iov[1];
 140         int rc, flags = 0;
 141         __le16 *utf16_path = NULL;
 142         u8 oplock = SMB2_OPLOCK_LEVEL_II;
 143         struct cifs_fid *pfid;
 144         struct dentry *dentry = NULL;
 145         struct cached_fid *cfid;
 146         struct cached_fids *cfids;
 147         const char *npath;
 148
 149         if (tcon == NULL || tcon->cfids == NULL || tcon->nohandlecache ||
 150             is_smb1_server(tcon->ses->server) || (dir_cache_timeout == 0))
 151                 return -EOPNOTSUPP;
 152
 153         ses = tcon->ses;
 154         server = ses->server;
 155         cfids = tcon->cfids;
 156
 157         if (!server->ops->new_lease_key)
 158                 return -EIO;
 159
 160         if (cifs_sb->root == NULL)
 161                 return -ENOENT;
 162
 163         utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
 164         if (!utf16_path)
 165                 return -ENOMEM;
 166
 167         cfid = find_or_create_cached_dir(cfids, path, lookup_only, tcon->max_cached_dirs);
 168         if (cfid == NULL) {
 169                 kfree(utf16_path);
 170                 return -ENOENT;
 171         }
 172         /*
 173          * Return cached fid if it has a lease.  Otherwise, it is either a new
 174          * entry or laundromat worker removed it from @cfids->entries.  Caller
 175          * will put last reference if the latter.
 176          */
 177         spin_lock(&cfids->cfid_list_lock);
 178         if (cfid->has_lease) {
 179                 spin_unlock(&cfids->cfid_list_lock);
 180                 *ret_cfid = cfid;
 181                 kfree(utf16_path);
 182                 return 0;
 183         }
 184         spin_unlock(&cfids->cfid_list_lock);
 185
 186         /*
 187          * Skip any prefix paths in @path as lookup_positive_unlocked() ends up
 188          * calling ->lookup() which already adds those through
 189          * build_path_from_dentry().  Also, do it earlier as we might reconnect
 190          * below when trying to send compounded request and then potentially
 191          * having a different prefix path (e.g. after DFS failover).
 192          */
 193         npath = path_no_prefix(cifs_sb, path);
 194         if (IS_ERR(npath)) {
 195                 rc = PTR_ERR(npath);
 196                 kfree(utf16_path);
 197                 return rc;
 198         }
 199
 200         /*
 201          * We do not hold the lock for the open because in case
 202          * SMB2_open needs to reconnect.
 203          * This is safe because no other thread will be able to get a ref
 204          * to the cfid until we have finished opening the file and (possibly)
 205          * acquired a lease.
 206          */
 207         if (smb3_encryption_required(tcon))
 208                 flags |= CIFS_TRANSFORM_REQ;
 209
 210         pfid = &cfid->fid;
 211         server->ops->new_lease_key(pfid);
 212
 213         memset(rqst, 0, sizeof(rqst));
 214         resp_buftype[0] = resp_buftype[1] = CIFS_NO_BUFFER;
 215         memset(rsp_iov, 0, sizeof(rsp_iov));
 216
 217         /* Open */
 218         memset(&open_iov, 0, sizeof(open_iov));
 219         rqst[0].rq_iov = open_iov;
 220         rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE;
 221
 222         oparms = (struct cifs_open_parms) {
 223                 .tcon = tcon,
 224                 .path = path,
 225                 .create_options = cifs_create_options(cifs_sb, CREATE_NOT_FILE),
 226                 .desired_access =  FILE_READ_DATA | FILE_READ_ATTRIBUTES,
 227                 .disposition = FILE_OPEN,
 228                 .fid = pfid,
 229         };
 230
 231         rc = SMB2_open_init(tcon, server,
 232                             &rqst[0], &oplock, &oparms, utf16_path);
 233         if (rc)
 234                 goto oshr_free;
 235         smb2_set_next_command(tcon, &rqst[0]);
 236
 237         memset(&qi_iov, 0, sizeof(qi_iov));
 238         rqst[1].rq_iov = qi_iov;
 239         rqst[1].rq_nvec = 1;
 240
 241         rc = SMB2_query_info_init(tcon, server,
 242                                   &rqst[1], COMPOUND_FID,
 243                                   COMPOUND_FID, FILE_ALL_INFORMATION,
 244                                   SMB2_O_INFO_FILE, 0,
 245                                   sizeof(struct smb2_file_all_info) +
 246                                   PATH_MAX * 2, 0, NULL);
 247         if (rc)
 248                 goto oshr_free;
 249
 250         smb2_set_related(&rqst[1]);
 251
 252         rc = compound_send_recv(xid, ses, server,
 253                                 flags, 2, rqst,
 254                                 resp_buftype, rsp_iov);
 255         if (rc) {
 256                 if (rc == -EREMCHG) {
 257                         tcon->need_reconnect = true;
 258                         pr_warn_once("server share %s deleted\n",
 259                                      tcon->tree_name);
 260                 }
 261                 goto oshr_free;
 262         }
 263         cfid->tcon = tcon;
 264         cfid->is_open = true;
 265
 266         o_rsp = (struct smb2_create_rsp *)rsp_iov[0].iov_base;
 267         oparms.fid->persistent_fid = o_rsp->PersistentFileId;
 268         oparms.fid->volatile_fid = o_rsp->VolatileFileId;
 269 #ifdef CONFIG_CIFS_DEBUG2
 270         oparms.fid->mid = le64_to_cpu(o_rsp->hdr.MessageId);
 271 #endif /* CIFS_DEBUG2 */
 272
 273         if (o_rsp->OplockLevel != SMB2_OPLOCK_LEVEL_LEASE)
 274                 goto oshr_free;
 275
 276         smb2_parse_contexts(server, o_rsp,
 277                             &oparms.fid->epoch,
 278                             oparms.fid->lease_key, &oplock,
 279                             NULL, NULL);
 280         if (!(oplock & SMB2_LEASE_READ_CACHING_HE))
 281                 goto oshr_free;
 282         qi_rsp = (struct smb2_query_info_rsp *)rsp_iov[1].iov_base;
 283         if (le32_to_cpu(qi_rsp->OutputBufferLength) < sizeof(struct smb2_file_all_info))
 284                 goto oshr_free;
 285         if (!smb2_validate_and_copy_iov(
 286                                 le16_to_cpu(qi_rsp->OutputBufferOffset),
 287                                 sizeof(struct smb2_file_all_info),
 288                                 &rsp_iov[1], sizeof(struct smb2_file_all_info),
 289                                 (char *)&cfid->file_all_info))
 290                 cfid->file_all_info_is_valid = true;
 291
 292         if (!npath[0])
 293                 dentry = dget(cifs_sb->root);
 294         else {
 295                 dentry = path_to_dentry(cifs_sb, npath);
 296                 if (IS_ERR(dentry)) {
 297                         rc = -ENOENT;
 298                         goto oshr_free;
 299                 }
 300         }
 301         spin_lock(&cfids->cfid_list_lock);
 302         cfid->dentry = dentry;
 303         cfid->time = jiffies;
 304         cfid->has_lease = true;
 305         spin_unlock(&cfids->cfid_list_lock);
 306
 307 oshr_free:
 308         kfree(utf16_path);
 309         SMB2_open_free(&rqst[0]);
 310         SMB2_query_info_free(&rqst[1]);
 311         free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
 312         free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
 313         spin_lock(&cfids->cfid_list_lock);
 314         if (!cfid->has_lease) {
 315                 if (rc) {
 316                         if (cfid->on_list) {
 317                                 list_del(&cfid->entry);
 318                                 cfid->on_list = false;
 319                                 cfids->num_entries--;
 320                         }
 321                         rc = -ENOENT;
 322                 } else {
 323                         /*
 324                          * We are guaranteed to have two references at this
 325                          * point. One for the caller and one for a potential
 326                          * lease. Release the Lease-ref so that the directory
 327                          * will be closed when the caller closes the cached
 328                          * handle.
 329                          */
 330                         spin_unlock(&cfids->cfid_list_lock);
 331                         kref_put(&cfid->refcount, smb2_close_cached_fid);
 332                         goto out;
 333                 }
 334         }
 335         spin_unlock(&cfids->cfid_list_lock);
 336         if (rc) {
 337                 if (cfid->is_open)
 338                         SMB2_close(0, cfid->tcon, cfid->fid.persistent_fid,
 339                                    cfid->fid.volatile_fid);
 340                 free_cached_dir(cfid);
 341                 cfid = NULL;
 342         }
 343 out:
 344         if (rc == 0) {
 345                 *ret_cfid = cfid;
 346                 atomic_inc(&tcon->num_remote_opens);
 347         }
 348
 349         return rc;
 350 }
 351
 352 int open_cached_dir_by_dentry(struct cifs_tcon *tcon,
 353                               struct dentry *dentry,
 354                               struct cached_fid **ret_cfid)
 355 {
 356         struct cached_fid *cfid;
 357         struct cached_fids *cfids = tcon->cfids;
 358
 359         if (cfids == NULL)
 360                 return -ENOENT;
 361
 362         spin_lock(&cfids->cfid_list_lock);
 363         list_for_each_entry(cfid, &cfids->entries, entry) {
 364                 if (dentry && cfid->dentry == dentry) {
 365                         cifs_dbg(FYI, "found a cached root file handle by dentry\n");
 366                         kref_get(&cfid->refcount);
 367                         *ret_cfid = cfid;
 368                         spin_unlock(&cfids->cfid_list_lock);
 369                         return 0;
 370                 }
 371         }
 372         spin_unlock(&cfids->cfid_list_lock);
 373         return -ENOENT;
 374 }
 375
 376 static void
 377 smb2_close_cached_fid(struct kref *ref)
 378 {
 379         struct cached_fid *cfid = container_of(ref, struct cached_fid,
 380                                                refcount);
 381
 382         spin_lock(&cfid->cfids->cfid_list_lock);
 383         if (cfid->on_list) {
 384                 list_del(&cfid->entry);
 385                 cfid->on_list = false;
 386                 cfid->cfids->num_entries--;
 387         }
 388         spin_unlock(&cfid->cfids->cfid_list_lock);
 389
 390         dput(cfid->dentry);
 391         cfid->dentry = NULL;
 392
 393         if (cfid->is_open) {
 394                 SMB2_close(0, cfid->tcon, cfid->fid.persistent_fid,
 395                            cfid->fid.volatile_fid);
 396                 atomic_dec(&cfid->tcon->num_remote_opens);
 397         }
 398
 399         free_cached_dir(cfid);
 400 }
 401
 402 void drop_cached_dir_by_name(const unsigned int xid, struct cifs_tcon *tcon,
 403                              const char *name, struct cifs_sb_info *cifs_sb)
 404 {
 405         struct cached_fid *cfid = NULL;
 406         int rc;
 407
 408         rc = open_cached_dir(xid, tcon, name, cifs_sb, true, &cfid);
 409         if (rc) {
 410                 cifs_dbg(FYI, "no cached dir found for rmdir(%s)\n", name);
 411                 return;
 412         }
 413         spin_lock(&cfid->cfids->cfid_list_lock);
 414         if (cfid->has_lease) {
 415                 cfid->has_lease = false;
 416                 kref_put(&cfid->refcount, smb2_close_cached_fid);
 417         }
 418         spin_unlock(&cfid->cfids->cfid_list_lock);
 419         close_cached_dir(cfid);
 420 }
 421
 422
 423 void close_cached_dir(struct cached_fid *cfid)
 424 {
 425         kref_put(&cfid->refcount, smb2_close_cached_fid);
 426 }
 427
 428 /*
 429  * Called from cifs_kill_sb when we unmount a share
 430  */
 431 void close_all_cached_dirs(struct cifs_sb_info *cifs_sb)
 432 {
 433         struct rb_root *root = &cifs_sb->tlink_tree;
 434         struct rb_node *node;
 435         struct cached_fid *cfid;
 436         struct cifs_tcon *tcon;
 437         struct tcon_link *tlink;
 438         struct cached_fids *cfids;
 439
 440         for (node = rb_first(root); node; node = rb_next(node)) {
 441                 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
 442                 tcon = tlink_tcon(tlink);
 443                 if (IS_ERR(tcon))
 444                         continue;
 445                 cfids = tcon->cfids;
 446                 if (cfids == NULL)
 447                         continue;
 448                 list_for_each_entry(cfid, &cfids->entries, entry) {
 449                         dput(cfid->dentry);
 450                         cfid->dentry = NULL;
 451                 }
 452         }
 453 }
 454
 455 /*
 456  * Invalidate all cached dirs when a TCON has been reset
 457  * due to a session loss.
 458  */
 459 void invalidate_all_cached_dirs(struct cifs_tcon *tcon)
 460 {
 461         struct cached_fids *cfids = tcon->cfids;
 462         struct cached_fid *cfid, *q;
 463         LIST_HEAD(entry);
 464
 465         if (cfids == NULL)
 466                 return;
 467
 468         spin_lock(&cfids->cfid_list_lock);
 469         list_for_each_entry_safe(cfid, q, &cfids->entries, entry) {
 470                 list_move(&cfid->entry, &entry);
 471                 cfids->num_entries--;
 472                 cfid->is_open = false;
 473                 cfid->on_list = false;
 474                 /* To prevent race with smb2_cached_lease_break() */
 475                 kref_get(&cfid->refcount);
 476         }
 477         spin_unlock(&cfids->cfid_list_lock);
 478
 479         list_for_each_entry_safe(cfid, q, &entry, entry) {
 480                 list_del(&cfid->entry);
 481                 cancel_work_sync(&cfid->lease_break);
 482                 if (cfid->has_lease) {
 483                         /*
 484                          * We lease was never cancelled from the server so we
 485                          * need to drop the reference.
 486                          */
 487                         spin_lock(&cfids->cfid_list_lock);
 488                         cfid->has_lease = false;
 489                         spin_unlock(&cfids->cfid_list_lock);
 490                         kref_put(&cfid->refcount, smb2_close_cached_fid);
 491                 }
 492                 /* Drop the extra reference opened above*/
 493                 kref_put(&cfid->refcount, smb2_close_cached_fid);
 494         }
 495 }
 496
 497 static void
 498 smb2_cached_lease_break(struct work_struct *work)
 499 {
 500         struct cached_fid *cfid = container_of(work,
 501                                 struct cached_fid, lease_break);
 502
 503         spin_lock(&cfid->cfids->cfid_list_lock);
 504         cfid->has_lease = false;
 505         spin_unlock(&cfid->cfids->cfid_list_lock);
 506         kref_put(&cfid->refcount, smb2_close_cached_fid);
 507 }
 508
 509 int cached_dir_lease_break(struct cifs_tcon *tcon, __u8 lease_key[16])
 510 {
 511         struct cached_fids *cfids = tcon->cfids;
 512         struct cached_fid *cfid;
 513
 514         if (cfids == NULL)
 515                 return false;
 516
 517         spin_lock(&cfids->cfid_list_lock);
 518         list_for_each_entry(cfid, &cfids->entries, entry) {
 519                 if (cfid->has_lease &&
 520                     !memcmp(lease_key,
 521                             cfid->fid.lease_key,
 522                             SMB2_LEASE_KEY_SIZE)) {
 523                         cfid->time = 0;
 524                         /*
 525                          * We found a lease remove it from the list
 526                          * so no threads can access it.
 527                          */
 528                         list_del(&cfid->entry);
 529                         cfid->on_list = false;
 530                         cfids->num_entries--;
 531
 532                         queue_work(cifsiod_wq,
 533                                    &cfid->lease_break);
 534                         spin_unlock(&cfids->cfid_list_lock);
 535                         return true;
 536                 }
 537         }
 538         spin_unlock(&cfids->cfid_list_lock);
 539         return false;
 540 }
 541
 542 static struct cached_fid *init_cached_dir(const char *path)
 543 {
 544         struct cached_fid *cfid;
 545
 546         cfid = kzalloc(sizeof(*cfid), GFP_ATOMIC);
 547         if (!cfid)
 548                 return NULL;
 549         cfid->path = kstrdup(path, GFP_ATOMIC);
 550         if (!cfid->path) {
 551                 kfree(cfid);
 552                 return NULL;
 553         }
 554
 555         INIT_WORK(&cfid->lease_break, smb2_cached_lease_break);
 556         INIT_LIST_HEAD(&cfid->entry);
 557         INIT_LIST_HEAD(&cfid->dirents.entries);
 558         mutex_init(&cfid->dirents.de_mutex);
 559         spin_lock_init(&cfid->fid_lock);
 560         kref_init(&cfid->refcount);
 561         return cfid;
 562 }
 563
 564 static void free_cached_dir(struct cached_fid *cfid)
 565 {
 566         struct cached_dirent *dirent, *q;
 567
 568         dput(cfid->dentry);
 569         cfid->dentry = NULL;
 570
 571         /*
 572          * Delete all cached dirent names
 573          */
 574         list_for_each_entry_safe(dirent, q, &cfid->dirents.entries, entry) {
 575                 list_del(&dirent->entry);
 576                 kfree(dirent->name);
 577                 kfree(dirent);
 578         }
 579
 580         kfree(cfid->path);
 581         cfid->path = NULL;
 582         kfree(cfid);
 583 }
 584
 585 static void cfids_laundromat_worker(struct work_struct *work)
 586 {
 587         struct cached_fids *cfids;
 588         struct cached_fid *cfid, *q;
 589         LIST_HEAD(entry);
 590
 591         cfids = container_of(work, struct cached_fids, laundromat_work.work);
 592
 593         spin_lock(&cfids->cfid_list_lock);
 594         list_for_each_entry_safe(cfid, q, &cfids->entries, entry) {
 595                 if (cfid->time &&
 596                     time_after(jiffies, cfid->time + HZ * dir_cache_timeout)) {
 597                         cfid->on_list = false;
 598                         list_move(&cfid->entry, &entry);
 599                         cfids->num_entries--;
 600                         /* To prevent race with smb2_cached_lease_break() */
 601                         kref_get(&cfid->refcount);
 602                 }
 603         }
 604         spin_unlock(&cfids->cfid_list_lock);
 605
 606         list_for_each_entry_safe(cfid, q, &entry, entry) {
 607                 list_del(&cfid->entry);
 608                 /*
 609                  * Cancel and wait for the work to finish in case we are racing
 610                  * with it.
 611                  */
 612                 cancel_work_sync(&cfid->lease_break);
 613                 if (cfid->has_lease) {
 614                         /*
 615                          * Our lease has not yet been cancelled from the server
 616                          * so we need to drop the reference.
 617                          */
 618                         spin_lock(&cfids->cfid_list_lock);
 619                         cfid->has_lease = false;
 620                         spin_unlock(&cfids->cfid_list_lock);
 621                         kref_put(&cfid->refcount, smb2_close_cached_fid);
 622                 }
 623                 /* Drop the extra reference opened above */
 624                 kref_put(&cfid->refcount, smb2_close_cached_fid);
 625         }
 626         queue_delayed_work(cifsiod_wq, &cfids->laundromat_work,
 627                            dir_cache_timeout * HZ);
 628 }
 629
 630 struct cached_fids *init_cached_dirs(void)
 631 {
 632         struct cached_fids *cfids;
 633
 634         cfids = kzalloc(sizeof(*cfids), GFP_KERNEL);
 635         if (!cfids)
 636                 return NULL;
 637         spin_lock_init(&cfids->cfid_list_lock);
 638         INIT_LIST_HEAD(&cfids->entries);
 639
 640         INIT_DELAYED_WORK(&cfids->laundromat_work, cfids_laundromat_worker);
 641         queue_delayed_work(cifsiod_wq, &cfids->laundromat_work,
 642                            dir_cache_timeout * HZ);
 643
 644         return cfids;
 645 }
 646
 647 /*
 648  * Called from tconInfoFree when we are tearing down the tcon.
 649  * There are no active users or open files/directories at this point.
 650  */
 651 void free_cached_dirs(struct cached_fids *cfids)
 652 {
 653         struct cached_fid *cfid, *q;
 654         LIST_HEAD(entry);
 655
 656         if (cfids == NULL)
 657                 return;
 658
 659         cancel_delayed_work_sync(&cfids->laundromat_work);
 660
 661         spin_lock(&cfids->cfid_list_lock);
 662         list_for_each_entry_safe(cfid, q, &cfids->entries, entry) {
 663                 cfid->on_list = false;
 664                 cfid->is_open = false;
 665                 list_move(&cfid->entry, &entry);
 666         }
 667         spin_unlock(&cfids->cfid_list_lock);
 668
 669         list_for_each_entry_safe(cfid, q, &entry, entry) {
 670                 list_del(&cfid->entry);
 671                 free_cached_dir(cfid);
 672         }
 673
 674         kfree(cfids);
 675 }