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->time || !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 int retries = 0, cur_sleep = 1; 149 150 if (tcon == NULL || tcon->cfids == NULL || tcon->nohandlecache || 151 is_smb1_server(tcon->ses->server) || (dir_cache_timeout == 0)) 152 return -EOPNOTSUPP; 153 154 ses = tcon->ses; 155 cfids = tcon->cfids; 156 157 if (cifs_sb->root == NULL) 158 return -ENOENT; 159 160 replay_again: 161 /* reinitialize for possible replay */ 162 flags = 0; 163 oplock = SMB2_OPLOCK_LEVEL_II; 164 server = cifs_pick_channel(ses); 165 166 if (!server->ops->new_lease_key) 167 return -EIO; 168 169 utf16_path = cifs_convert_path_to_utf16(path, cifs_sb); 170 if (!utf16_path) 171 return -ENOMEM; 172 173 cfid = find_or_create_cached_dir(cfids, path, lookup_only, tcon->max_cached_dirs); 174 if (cfid == NULL) { 175 kfree(utf16_path); 176 return -ENOENT; 177 } 178 /* 179 * Return cached fid if it has a lease. Otherwise, it is either a new 180 * entry or laundromat worker removed it from @cfids->entries. Caller 181 * will put last reference if the latter. 182 */ 183 spin_lock(&cfids->cfid_list_lock); 184 if (cfid->has_lease) { 185 spin_unlock(&cfids->cfid_list_lock); 186 *ret_cfid = cfid; 187 kfree(utf16_path); 188 return 0; 189 } 190 spin_unlock(&cfids->cfid_list_lock); 191 192 /* 193 * Skip any prefix paths in @path as lookup_positive_unlocked() ends up 194 * calling ->lookup() which already adds those through 195 * build_path_from_dentry(). Also, do it earlier as we might reconnect 196 * below when trying to send compounded request and then potentially 197 * having a different prefix path (e.g. after DFS failover). 198 */ 199 npath = path_no_prefix(cifs_sb, path); 200 if (IS_ERR(npath)) { 201 rc = PTR_ERR(npath); 202 goto out; 203 } 204 205 if (!npath[0]) { 206 dentry = dget(cifs_sb->root); 207 } else { 208 dentry = path_to_dentry(cifs_sb, npath); 209 if (IS_ERR(dentry)) { 210 rc = -ENOENT; 211 goto out; 212 } 213 } 214 cfid->dentry = dentry; 215 216 /* 217 * We do not hold the lock for the open because in case 218 * SMB2_open needs to reconnect. 219 * This is safe because no other thread will be able to get a ref 220 * to the cfid until we have finished opening the file and (possibly) 221 * acquired a lease. 222 */ 223 if (smb3_encryption_required(tcon)) 224 flags |= CIFS_TRANSFORM_REQ; 225 226 pfid = &cfid->fid; 227 server->ops->new_lease_key(pfid); 228 229 memset(rqst, 0, sizeof(rqst)); 230 resp_buftype[0] = resp_buftype[1] = CIFS_NO_BUFFER; 231 memset(rsp_iov, 0, sizeof(rsp_iov)); 232 233 /* Open */ 234 memset(&open_iov, 0, sizeof(open_iov)); 235 rqst[0].rq_iov = open_iov; 236 rqst[0].rq_nvec = SMB2_CREATE_IOV_SIZE; 237 238 oparms = (struct cifs_open_parms) { 239 .tcon = tcon, 240 .path = path, 241 .create_options = cifs_create_options(cifs_sb, CREATE_NOT_FILE), 242 .desired_access = FILE_READ_DATA | FILE_READ_ATTRIBUTES, 243 .disposition = FILE_OPEN, 244 .fid = pfid, 245 }; 246 247 rc = SMB2_open_init(tcon, server, 248 &rqst[0], &oplock, &oparms, utf16_path); 249 if (rc) 250 goto oshr_free; 251 smb2_set_next_command(tcon, &rqst[0]); 252 253 memset(&qi_iov, 0, sizeof(qi_iov)); 254 rqst[1].rq_iov = qi_iov; 255 rqst[1].rq_nvec = 1; 256 257 rc = SMB2_query_info_init(tcon, server, 258 &rqst[1], COMPOUND_FID, 259 COMPOUND_FID, FILE_ALL_INFORMATION, 260 SMB2_O_INFO_FILE, 0, 261 sizeof(struct smb2_file_all_info) + 262 PATH_MAX * 2, 0, NULL); 263 if (rc) 264 goto oshr_free; 265 266 smb2_set_related(&rqst[1]); 267 268 /* 269 * Set @cfid->has_lease to true before sending out compounded request so 270 * its lease reference can be put in cached_dir_lease_break() due to a 271 * potential lease break right after the request is sent or while @cfid 272 * is still being cached. Concurrent processes won't be to use it yet 273 * due to @cfid->time being zero. 274 */ 275 cfid->has_lease = true; 276 277 if (retries) { 278 smb2_set_replay(server, &rqst[0]); 279 smb2_set_replay(server, &rqst[1]); 280 } 281 282 rc = compound_send_recv(xid, ses, server, 283 flags, 2, rqst, 284 resp_buftype, rsp_iov); 285 if (rc) { 286 if (rc == -EREMCHG) { 287 tcon->need_reconnect = true; 288 pr_warn_once("server share %s deleted\n", 289 tcon->tree_name); 290 } 291 goto oshr_free; 292 } 293 cfid->tcon = tcon; 294 cfid->is_open = true; 295 296 spin_lock(&cfids->cfid_list_lock); 297 298 o_rsp = (struct smb2_create_rsp *)rsp_iov[0].iov_base; 299 oparms.fid->persistent_fid = o_rsp->PersistentFileId; 300 oparms.fid->volatile_fid = o_rsp->VolatileFileId; 301 #ifdef CONFIG_CIFS_DEBUG2 302 oparms.fid->mid = le64_to_cpu(o_rsp->hdr.MessageId); 303 #endif /* CIFS_DEBUG2 */ 304 305 306 if (o_rsp->OplockLevel != SMB2_OPLOCK_LEVEL_LEASE) { 307 spin_unlock(&cfids->cfid_list_lock); 308 rc = -EINVAL; 309 goto oshr_free; 310 } 311 312 rc = smb2_parse_contexts(server, rsp_iov, 313 &oparms.fid->epoch, 314 oparms.fid->lease_key, 315 &oplock, NULL, NULL); 316 if (rc) { 317 spin_unlock(&cfids->cfid_list_lock); 318 goto oshr_free; 319 } 320 321 rc = -EINVAL; 322 if (!(oplock & SMB2_LEASE_READ_CACHING_HE)) { 323 spin_unlock(&cfids->cfid_list_lock); 324 goto oshr_free; 325 } 326 qi_rsp = (struct smb2_query_info_rsp *)rsp_iov[1].iov_base; 327 if (le32_to_cpu(qi_rsp->OutputBufferLength) < sizeof(struct smb2_file_all_info)) { 328 spin_unlock(&cfids->cfid_list_lock); 329 goto oshr_free; 330 } 331 if (!smb2_validate_and_copy_iov( 332 le16_to_cpu(qi_rsp->OutputBufferOffset), 333 sizeof(struct smb2_file_all_info), 334 &rsp_iov[1], sizeof(struct smb2_file_all_info), 335 (char *)&cfid->file_all_info)) 336 cfid->file_all_info_is_valid = true; 337 338 cfid->time = jiffies; 339 spin_unlock(&cfids->cfid_list_lock); 340 /* At this point the directory handle is fully cached */ 341 rc = 0; 342 343 oshr_free: 344 SMB2_open_free(&rqst[0]); 345 SMB2_query_info_free(&rqst[1]); 346 free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base); 347 free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base); 348 if (rc) { 349 spin_lock(&cfids->cfid_list_lock); 350 if (cfid->on_list) { 351 list_del(&cfid->entry); 352 cfid->on_list = false; 353 cfids->num_entries--; 354 } 355 if (cfid->has_lease) { 356 /* 357 * We are guaranteed to have two references at this 358 * point. One for the caller and one for a potential 359 * lease. Release the Lease-ref so that the directory 360 * will be closed when the caller closes the cached 361 * handle. 362 */ 363 cfid->has_lease = false; 364 spin_unlock(&cfids->cfid_list_lock); 365 kref_put(&cfid->refcount, smb2_close_cached_fid); 366 goto out; 367 } 368 spin_unlock(&cfids->cfid_list_lock); 369 } 370 out: 371 if (rc) { 372 if (cfid->is_open) 373 SMB2_close(0, cfid->tcon, cfid->fid.persistent_fid, 374 cfid->fid.volatile_fid); 375 free_cached_dir(cfid); 376 } else { 377 *ret_cfid = cfid; 378 atomic_inc(&tcon->num_remote_opens); 379 } 380 kfree(utf16_path); 381 382 if (is_replayable_error(rc) && 383 smb2_should_replay(tcon, &retries, &cur_sleep)) 384 goto replay_again; 385 386 return rc; 387 } 388 389 int open_cached_dir_by_dentry(struct cifs_tcon *tcon, 390 struct dentry *dentry, 391 struct cached_fid **ret_cfid) 392 { 393 struct cached_fid *cfid; 394 struct cached_fids *cfids = tcon->cfids; 395 396 if (cfids == NULL) 397 return -ENOENT; 398 399 spin_lock(&cfids->cfid_list_lock); 400 list_for_each_entry(cfid, &cfids->entries, entry) { 401 if (dentry && cfid->dentry == dentry) { 402 cifs_dbg(FYI, "found a cached root file handle by dentry\n"); 403 kref_get(&cfid->refcount); 404 *ret_cfid = cfid; 405 spin_unlock(&cfids->cfid_list_lock); 406 return 0; 407 } 408 } 409 spin_unlock(&cfids->cfid_list_lock); 410 return -ENOENT; 411 } 412 413 static void 414 smb2_close_cached_fid(struct kref *ref) 415 { 416 struct cached_fid *cfid = container_of(ref, struct cached_fid, 417 refcount); 418 419 spin_lock(&cfid->cfids->cfid_list_lock); 420 if (cfid->on_list) { 421 list_del(&cfid->entry); 422 cfid->on_list = false; 423 cfid->cfids->num_entries--; 424 } 425 spin_unlock(&cfid->cfids->cfid_list_lock); 426 427 dput(cfid->dentry); 428 cfid->dentry = NULL; 429 430 if (cfid->is_open) { 431 SMB2_close(0, cfid->tcon, cfid->fid.persistent_fid, 432 cfid->fid.volatile_fid); 433 atomic_dec(&cfid->tcon->num_remote_opens); 434 } 435 436 free_cached_dir(cfid); 437 } 438 439 void drop_cached_dir_by_name(const unsigned int xid, struct cifs_tcon *tcon, 440 const char *name, struct cifs_sb_info *cifs_sb) 441 { 442 struct cached_fid *cfid = NULL; 443 int rc; 444 445 rc = open_cached_dir(xid, tcon, name, cifs_sb, true, &cfid); 446 if (rc) { 447 cifs_dbg(FYI, "no cached dir found for rmdir(%s)\n", name); 448 return; 449 } 450 spin_lock(&cfid->cfids->cfid_list_lock); 451 if (cfid->has_lease) { 452 cfid->has_lease = false; 453 kref_put(&cfid->refcount, smb2_close_cached_fid); 454 } 455 spin_unlock(&cfid->cfids->cfid_list_lock); 456 close_cached_dir(cfid); 457 } 458 459 460 void close_cached_dir(struct cached_fid *cfid) 461 { 462 kref_put(&cfid->refcount, smb2_close_cached_fid); 463 } 464 465 /* 466 * Called from cifs_kill_sb when we unmount a share 467 */ 468 void close_all_cached_dirs(struct cifs_sb_info *cifs_sb) 469 { 470 struct rb_root *root = &cifs_sb->tlink_tree; 471 struct rb_node *node; 472 struct cached_fid *cfid; 473 struct cifs_tcon *tcon; 474 struct tcon_link *tlink; 475 struct cached_fids *cfids; 476 477 for (node = rb_first(root); node; node = rb_next(node)) { 478 tlink = rb_entry(node, struct tcon_link, tl_rbnode); 479 tcon = tlink_tcon(tlink); 480 if (IS_ERR(tcon)) 481 continue; 482 cfids = tcon->cfids; 483 if (cfids == NULL) 484 continue; 485 list_for_each_entry(cfid, &cfids->entries, entry) { 486 dput(cfid->dentry); 487 cfid->dentry = NULL; 488 } 489 } 490 } 491 492 /* 493 * Invalidate all cached dirs when a TCON has been reset 494 * due to a session loss. 495 */ 496 void invalidate_all_cached_dirs(struct cifs_tcon *tcon) 497 { 498 struct cached_fids *cfids = tcon->cfids; 499 struct cached_fid *cfid, *q; 500 LIST_HEAD(entry); 501 502 if (cfids == NULL) 503 return; 504 505 spin_lock(&cfids->cfid_list_lock); 506 list_for_each_entry_safe(cfid, q, &cfids->entries, entry) { 507 list_move(&cfid->entry, &entry); 508 cfids->num_entries--; 509 cfid->is_open = false; 510 cfid->on_list = false; 511 /* To prevent race with smb2_cached_lease_break() */ 512 kref_get(&cfid->refcount); 513 } 514 spin_unlock(&cfids->cfid_list_lock); 515 516 list_for_each_entry_safe(cfid, q, &entry, entry) { 517 list_del(&cfid->entry); 518 cancel_work_sync(&cfid->lease_break); 519 if (cfid->has_lease) { 520 /* 521 * We lease was never cancelled from the server so we 522 * need to drop the reference. 523 */ 524 spin_lock(&cfids->cfid_list_lock); 525 cfid->has_lease = false; 526 spin_unlock(&cfids->cfid_list_lock); 527 kref_put(&cfid->refcount, smb2_close_cached_fid); 528 } 529 /* Drop the extra reference opened above*/ 530 kref_put(&cfid->refcount, smb2_close_cached_fid); 531 } 532 } 533 534 static void 535 smb2_cached_lease_break(struct work_struct *work) 536 { 537 struct cached_fid *cfid = container_of(work, 538 struct cached_fid, lease_break); 539 540 spin_lock(&cfid->cfids->cfid_list_lock); 541 cfid->has_lease = false; 542 spin_unlock(&cfid->cfids->cfid_list_lock); 543 kref_put(&cfid->refcount, smb2_close_cached_fid); 544 } 545 546 int cached_dir_lease_break(struct cifs_tcon *tcon, __u8 lease_key[16]) 547 { 548 struct cached_fids *cfids = tcon->cfids; 549 struct cached_fid *cfid; 550 551 if (cfids == NULL) 552 return false; 553 554 spin_lock(&cfids->cfid_list_lock); 555 list_for_each_entry(cfid, &cfids->entries, entry) { 556 if (cfid->has_lease && 557 !memcmp(lease_key, 558 cfid->fid.lease_key, 559 SMB2_LEASE_KEY_SIZE)) { 560 cfid->time = 0; 561 /* 562 * We found a lease remove it from the list 563 * so no threads can access it. 564 */ 565 list_del(&cfid->entry); 566 cfid->on_list = false; 567 cfids->num_entries--; 568 569 queue_work(cifsiod_wq, 570 &cfid->lease_break); 571 spin_unlock(&cfids->cfid_list_lock); 572 return true; 573 } 574 } 575 spin_unlock(&cfids->cfid_list_lock); 576 return false; 577 } 578 579 static struct cached_fid *init_cached_dir(const char *path) 580 { 581 struct cached_fid *cfid; 582 583 cfid = kzalloc(sizeof(*cfid), GFP_ATOMIC); 584 if (!cfid) 585 return NULL; 586 cfid->path = kstrdup(path, GFP_ATOMIC); 587 if (!cfid->path) { 588 kfree(cfid); 589 return NULL; 590 } 591 592 INIT_WORK(&cfid->lease_break, smb2_cached_lease_break); 593 INIT_LIST_HEAD(&cfid->entry); 594 INIT_LIST_HEAD(&cfid->dirents.entries); 595 mutex_init(&cfid->dirents.de_mutex); 596 spin_lock_init(&cfid->fid_lock); 597 kref_init(&cfid->refcount); 598 return cfid; 599 } 600 601 static void free_cached_dir(struct cached_fid *cfid) 602 { 603 struct cached_dirent *dirent, *q; 604 605 dput(cfid->dentry); 606 cfid->dentry = NULL; 607 608 /* 609 * Delete all cached dirent names 610 */ 611 list_for_each_entry_safe(dirent, q, &cfid->dirents.entries, entry) { 612 list_del(&dirent->entry); 613 kfree(dirent->name); 614 kfree(dirent); 615 } 616 617 kfree(cfid->path); 618 cfid->path = NULL; 619 kfree(cfid); 620 } 621 622 static void cfids_laundromat_worker(struct work_struct *work) 623 { 624 struct cached_fids *cfids; 625 struct cached_fid *cfid, *q; 626 LIST_HEAD(entry); 627 628 cfids = container_of(work, struct cached_fids, laundromat_work.work); 629 630 spin_lock(&cfids->cfid_list_lock); 631 list_for_each_entry_safe(cfid, q, &cfids->entries, entry) { 632 if (cfid->time && 633 time_after(jiffies, cfid->time + HZ * dir_cache_timeout)) { 634 cfid->on_list = false; 635 list_move(&cfid->entry, &entry); 636 cfids->num_entries--; 637 /* To prevent race with smb2_cached_lease_break() */ 638 kref_get(&cfid->refcount); 639 } 640 } 641 spin_unlock(&cfids->cfid_list_lock); 642 643 list_for_each_entry_safe(cfid, q, &entry, entry) { 644 list_del(&cfid->entry); 645 /* 646 * Cancel and wait for the work to finish in case we are racing 647 * with it. 648 */ 649 cancel_work_sync(&cfid->lease_break); 650 if (cfid->has_lease) { 651 /* 652 * Our lease has not yet been cancelled from the server 653 * so we need to drop the reference. 654 */ 655 spin_lock(&cfids->cfid_list_lock); 656 cfid->has_lease = false; 657 spin_unlock(&cfids->cfid_list_lock); 658 kref_put(&cfid->refcount, smb2_close_cached_fid); 659 } 660 /* Drop the extra reference opened above */ 661 kref_put(&cfid->refcount, smb2_close_cached_fid); 662 } 663 queue_delayed_work(cifsiod_wq, &cfids->laundromat_work, 664 dir_cache_timeout * HZ); 665 } 666 667 struct cached_fids *init_cached_dirs(void) 668 { 669 struct cached_fids *cfids; 670 671 cfids = kzalloc(sizeof(*cfids), GFP_KERNEL); 672 if (!cfids) 673 return NULL; 674 spin_lock_init(&cfids->cfid_list_lock); 675 INIT_LIST_HEAD(&cfids->entries); 676 677 INIT_DELAYED_WORK(&cfids->laundromat_work, cfids_laundromat_worker); 678 queue_delayed_work(cifsiod_wq, &cfids->laundromat_work, 679 dir_cache_timeout * HZ); 680 681 return cfids; 682 } 683 684 /* 685 * Called from tconInfoFree when we are tearing down the tcon. 686 * There are no active users or open files/directories at this point. 687 */ 688 void free_cached_dirs(struct cached_fids *cfids) 689 { 690 struct cached_fid *cfid, *q; 691 LIST_HEAD(entry); 692 693 if (cfids == NULL) 694 return; 695 696 cancel_delayed_work_sync(&cfids->laundromat_work); 697 698 spin_lock(&cfids->cfid_list_lock); 699 list_for_each_entry_safe(cfid, q, &cfids->entries, entry) { 700 cfid->on_list = false; 701 cfid->is_open = false; 702 list_move(&cfid->entry, &entry); 703 } 704 spin_unlock(&cfids->cfid_list_lock); 705 706 list_for_each_entry_safe(cfid, q, &entry, entry) { 707 list_del(&cfid->entry); 708 free_cached_dir(cfid); 709 } 710 711 kfree(cfids); 712 } 713