1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* Daemon interface 3 * 4 * Copyright (C) 2007, 2021 Red Hat, Inc. All Rights Reserved. 5 * Written by David Howells (dhowells@redhat.com) 6 */ 7 8 #include <linux/module.h> 9 #include <linux/init.h> 10 #include <linux/sched.h> 11 #include <linux/completion.h> 12 #include <linux/slab.h> 13 #include <linux/fs.h> 14 #include <linux/file.h> 15 #include <linux/namei.h> 16 #include <linux/poll.h> 17 #include <linux/mount.h> 18 #include <linux/statfs.h> 19 #include <linux/ctype.h> 20 #include <linux/string.h> 21 #include <linux/fs_struct.h> 22 #include "internal.h" 23 24 static int cachefiles_daemon_open(struct inode *, struct file *); 25 static int cachefiles_daemon_release(struct inode *, struct file *); 26 static ssize_t cachefiles_daemon_read(struct file *, char __user *, size_t, 27 loff_t *); 28 static ssize_t cachefiles_daemon_write(struct file *, const char __user *, 29 size_t, loff_t *); 30 static __poll_t cachefiles_daemon_poll(struct file *, 31 struct poll_table_struct *); 32 static int cachefiles_daemon_frun(struct cachefiles_cache *, char *); 33 static int cachefiles_daemon_fcull(struct cachefiles_cache *, char *); 34 static int cachefiles_daemon_fstop(struct cachefiles_cache *, char *); 35 static int cachefiles_daemon_brun(struct cachefiles_cache *, char *); 36 static int cachefiles_daemon_bcull(struct cachefiles_cache *, char *); 37 static int cachefiles_daemon_bstop(struct cachefiles_cache *, char *); 38 static int cachefiles_daemon_cull(struct cachefiles_cache *, char *); 39 static int cachefiles_daemon_debug(struct cachefiles_cache *, char *); 40 static int cachefiles_daemon_dir(struct cachefiles_cache *, char *); 41 static int cachefiles_daemon_inuse(struct cachefiles_cache *, char *); 42 static int cachefiles_daemon_secctx(struct cachefiles_cache *, char *); 43 static int cachefiles_daemon_tag(struct cachefiles_cache *, char *); 44 static int cachefiles_daemon_bind(struct cachefiles_cache *, char *); 45 static void cachefiles_daemon_unbind(struct cachefiles_cache *); 46 47 static unsigned long cachefiles_open; 48 49 const struct file_operations cachefiles_daemon_fops = { 50 .owner = THIS_MODULE, 51 .open = cachefiles_daemon_open, 52 .release = cachefiles_daemon_release, 53 .read = cachefiles_daemon_read, 54 .write = cachefiles_daemon_write, 55 .poll = cachefiles_daemon_poll, 56 .llseek = noop_llseek, 57 }; 58 59 struct cachefiles_daemon_cmd { 60 char name[8]; 61 int (*handler)(struct cachefiles_cache *cache, char *args); 62 }; 63 64 static const struct cachefiles_daemon_cmd cachefiles_daemon_cmds[] = { 65 { "bind", cachefiles_daemon_bind }, 66 { "brun", cachefiles_daemon_brun }, 67 { "bcull", cachefiles_daemon_bcull }, 68 { "bstop", cachefiles_daemon_bstop }, 69 { "cull", cachefiles_daemon_cull }, 70 { "debug", cachefiles_daemon_debug }, 71 { "dir", cachefiles_daemon_dir }, 72 { "frun", cachefiles_daemon_frun }, 73 { "fcull", cachefiles_daemon_fcull }, 74 { "fstop", cachefiles_daemon_fstop }, 75 { "inuse", cachefiles_daemon_inuse }, 76 { "secctx", cachefiles_daemon_secctx }, 77 { "tag", cachefiles_daemon_tag }, 78 #ifdef CONFIG_CACHEFILES_ONDEMAND 79 { "copen", cachefiles_ondemand_copen }, 80 { "restore", cachefiles_ondemand_restore }, 81 #endif 82 { "", NULL } 83 }; 84 85 86 /* 87 * Prepare a cache for caching. 88 */ 89 static int cachefiles_daemon_open(struct inode *inode, struct file *file) 90 { 91 struct cachefiles_cache *cache; 92 93 _enter(""); 94 95 /* only the superuser may do this */ 96 if (!capable(CAP_SYS_ADMIN)) 97 return -EPERM; 98 99 /* the cachefiles device may only be open once at a time */ 100 if (xchg(&cachefiles_open, 1) == 1) 101 return -EBUSY; 102 103 /* allocate a cache record */ 104 cache = kzalloc(sizeof(struct cachefiles_cache), GFP_KERNEL); 105 if (!cache) { 106 cachefiles_open = 0; 107 return -ENOMEM; 108 } 109 110 mutex_init(&cache->daemon_mutex); 111 init_waitqueue_head(&cache->daemon_pollwq); 112 INIT_LIST_HEAD(&cache->volumes); 113 INIT_LIST_HEAD(&cache->object_list); 114 spin_lock_init(&cache->object_list_lock); 115 refcount_set(&cache->unbind_pincount, 1); 116 xa_init_flags(&cache->reqs, XA_FLAGS_ALLOC); 117 xa_init_flags(&cache->ondemand_ids, XA_FLAGS_ALLOC1); 118 119 /* set default caching limits 120 * - limit at 1% free space and/or free files 121 * - cull below 5% free space and/or free files 122 * - cease culling above 7% free space and/or free files 123 */ 124 cache->frun_percent = 7; 125 cache->fcull_percent = 5; 126 cache->fstop_percent = 1; 127 cache->brun_percent = 7; 128 cache->bcull_percent = 5; 129 cache->bstop_percent = 1; 130 131 file->private_data = cache; 132 cache->cachefilesd = file; 133 return 0; 134 } 135 136 void cachefiles_flush_reqs(struct cachefiles_cache *cache) 137 { 138 struct xarray *xa = &cache->reqs; 139 struct cachefiles_req *req; 140 unsigned long index; 141 142 /* 143 * Make sure the following two operations won't be reordered. 144 * 1) set CACHEFILES_DEAD bit 145 * 2) flush requests in the xarray 146 * Otherwise the request may be enqueued after xarray has been 147 * flushed, leaving the orphan request never being completed. 148 * 149 * CPU 1 CPU 2 150 * ===== ===== 151 * flush requests in the xarray 152 * test CACHEFILES_DEAD bit 153 * enqueue the request 154 * set CACHEFILES_DEAD bit 155 */ 156 smp_mb(); 157 158 xa_lock(xa); 159 xa_for_each(xa, index, req) { 160 req->error = -EIO; 161 complete(&req->done); 162 __xa_erase(xa, index); 163 } 164 xa_unlock(xa); 165 166 xa_destroy(&cache->reqs); 167 xa_destroy(&cache->ondemand_ids); 168 } 169 170 void cachefiles_put_unbind_pincount(struct cachefiles_cache *cache) 171 { 172 if (refcount_dec_and_test(&cache->unbind_pincount)) { 173 cachefiles_daemon_unbind(cache); 174 cachefiles_open = 0; 175 kfree(cache); 176 } 177 } 178 179 void cachefiles_get_unbind_pincount(struct cachefiles_cache *cache) 180 { 181 refcount_inc(&cache->unbind_pincount); 182 } 183 184 /* 185 * Release a cache. 186 */ 187 static int cachefiles_daemon_release(struct inode *inode, struct file *file) 188 { 189 struct cachefiles_cache *cache = file->private_data; 190 191 _enter(""); 192 193 ASSERT(cache); 194 195 set_bit(CACHEFILES_DEAD, &cache->flags); 196 197 if (cachefiles_in_ondemand_mode(cache)) 198 cachefiles_flush_reqs(cache); 199 200 /* clean up the control file interface */ 201 cache->cachefilesd = NULL; 202 file->private_data = NULL; 203 204 cachefiles_put_unbind_pincount(cache); 205 206 _leave(""); 207 return 0; 208 } 209 210 static ssize_t cachefiles_do_daemon_read(struct cachefiles_cache *cache, 211 char __user *_buffer, size_t buflen) 212 { 213 unsigned long long b_released; 214 unsigned f_released; 215 char buffer[256]; 216 int n; 217 218 /* check how much space the cache has */ 219 cachefiles_has_space(cache, 0, 0, cachefiles_has_space_check); 220 221 /* summarise */ 222 f_released = atomic_xchg(&cache->f_released, 0); 223 b_released = atomic_long_xchg(&cache->b_released, 0); 224 clear_bit(CACHEFILES_STATE_CHANGED, &cache->flags); 225 226 n = snprintf(buffer, sizeof(buffer), 227 "cull=%c" 228 " frun=%llx" 229 " fcull=%llx" 230 " fstop=%llx" 231 " brun=%llx" 232 " bcull=%llx" 233 " bstop=%llx" 234 " freleased=%x" 235 " breleased=%llx", 236 test_bit(CACHEFILES_CULLING, &cache->flags) ? '1' : '', 237 (unsigned long long) cache->frun, 238 (unsigned long long) cache->fcull, 239 (unsigned long long) cache->fstop, 240 (unsigned long long) cache->brun, 241 (unsigned long long) cache->bcull, 242 (unsigned long long) cache->bstop, 243 f_released, 244 b_released); 245 246 if (n > buflen) 247 return -EMSGSIZE; 248 249 if (copy_to_user(_buffer, buffer, n) != 0) 250 return -EFAULT; 251 252 return n; 253 } 254 255 /* 256 * Read the cache state. 257 */ 258 static ssize_t cachefiles_daemon_read(struct file *file, char __user *_buffer, 259 size_t buflen, loff_t *pos) 260 { 261 struct cachefiles_cache *cache = file->private_data; 262 263 //_enter(",,%zu,", buflen); 264 265 if (!test_bit(CACHEFILES_READY, &cache->flags)) 266 return 0; 267 268 if (cachefiles_in_ondemand_mode(cache)) 269 return cachefiles_ondemand_daemon_read(cache, _buffer, buflen); 270 else 271 return cachefiles_do_daemon_read(cache, _buffer, buflen); 272 } 273 274 /* 275 * Take a command from cachefilesd, parse it and act on it. 276 */ 277 static ssize_t cachefiles_daemon_write(struct file *file, 278 const char __user *_data, 279 size_t datalen, 280 loff_t *pos) 281 { 282 const struct cachefiles_daemon_cmd *cmd; 283 struct cachefiles_cache *cache = file->private_data; 284 ssize_t ret; 285 char *data, *args, *cp; 286 287 //_enter(",,%zu,", datalen); 288 289 ASSERT(cache); 290 291 if (test_bit(CACHEFILES_DEAD, &cache->flags)) 292 return -EIO; 293 294 if (datalen > PAGE_SIZE - 1) 295 return -EOPNOTSUPP; 296 297 /* drag the command string into the kernel so we can parse it */ 298 data = memdup_user_nul(_data, datalen); 299 if (IS_ERR(data)) 300 return PTR_ERR(data); 301 302 ret = -EINVAL; 303 if (memchr(data, '\0', datalen)) 304 goto error; 305 306 /* strip any newline */ 307 cp = memchr(data, '\n', datalen); 308 if (cp) { 309 if (cp == data) 310 goto error; 311 312 *cp = '\0'; 313 } 314 315 /* parse the command */ 316 ret = -EOPNOTSUPP; 317 318 for (args = data; *args; args++) 319 if (isspace(*args)) 320 break; 321 if (*args) { 322 if (args == data) 323 goto error; 324 *args = '\0'; 325 args = skip_spaces(++args); 326 } 327 328 /* run the appropriate command handler */ 329 for (cmd = cachefiles_daemon_cmds; cmd->name[0]; cmd++) 330 if (strcmp(cmd->name, data) == 0) 331 goto found_command; 332 333 error: 334 kfree(data); 335 //_leave(" = %zd", ret); 336 return ret; 337 338 found_command: 339 mutex_lock(&cache->daemon_mutex); 340 341 ret = -EIO; 342 if (!test_bit(CACHEFILES_DEAD, &cache->flags)) 343 ret = cmd->handler(cache, args); 344 345 mutex_unlock(&cache->daemon_mutex); 346 347 if (ret == 0) 348 ret = datalen; 349 goto error; 350 } 351 352 /* 353 * Poll for culling state 354 * - use EPOLLOUT to indicate culling state 355 */ 356 static __poll_t cachefiles_daemon_poll(struct file *file, 357 struct poll_table_struct *poll) 358 { 359 struct cachefiles_cache *cache = file->private_data; 360 XA_STATE(xas, &cache->reqs, 0); 361 struct cachefiles_req *req; 362 __poll_t mask; 363 364 poll_wait(file, &cache->daemon_pollwq, poll); 365 mask = 0; 366 367 if (cachefiles_in_ondemand_mode(cache)) { 368 if (!xa_empty(&cache->reqs)) { 369 xas_lock(&xas); 370 xas_for_each_marked(&xas, req, ULONG_MAX, CACHEFILES_REQ_NEW) { 371 if (!cachefiles_ondemand_is_reopening_read(req)) { 372 mask |= EPOLLIN; 373 break; 374 } 375 } 376 xas_unlock(&xas); 377 } 378 } else { 379 if (test_bit(CACHEFILES_STATE_CHANGED, &cache->flags)) 380 mask |= EPOLLIN; 381 } 382 383 if (test_bit(CACHEFILES_CULLING, &cache->flags)) 384 mask |= EPOLLOUT; 385 386 return mask; 387 } 388 389 /* 390 * Give a range error for cache space constraints 391 * - can be tail-called 392 */ 393 static int cachefiles_daemon_range_error(struct cachefiles_cache *cache, 394 char *args) 395 { 396 pr_err("Free space limits must be in range 0%%<=stop<cull<run<100%%\n"); 397 398 return -EINVAL; 399 } 400 401 /* 402 * Set the percentage of files at which to stop culling 403 * - command: "frun <N>%" 404 */ 405 static int cachefiles_daemon_frun(struct cachefiles_cache *cache, char *args) 406 { 407 unsigned long frun; 408 409 _enter(",%s", args); 410 411 if (!*args) 412 return -EINVAL; 413 414 frun = simple_strtoul(args, &args, 10); 415 if (args[0] != '%' || args[1] != '\0') 416 return -EINVAL; 417 418 if (frun <= cache->fcull_percent || frun >= 100) 419 return cachefiles_daemon_range_error(cache, args); 420 421 cache->frun_percent = frun; 422 return 0; 423 } 424 425 /* 426 * Set the percentage of files at which to start culling 427 * - command: "fcull <N>%" 428 */ 429 static int cachefiles_daemon_fcull(struct cachefiles_cache *cache, char *args) 430 { 431 unsigned long fcull; 432 433 _enter(",%s", args); 434 435 if (!*args) 436 return -EINVAL; 437 438 fcull = simple_strtoul(args, &args, 10); 439 if (args[0] != '%' || args[1] != '\0') 440 return -EINVAL; 441 442 if (fcull <= cache->fstop_percent || fcull >= cache->frun_percent) 443 return cachefiles_daemon_range_error(cache, args); 444 445 cache->fcull_percent = fcull; 446 return 0; 447 } 448 449 /* 450 * Set the percentage of files at which to stop allocating 451 * - command: "fstop <N>%" 452 */ 453 static int cachefiles_daemon_fstop(struct cachefiles_cache *cache, char *args) 454 { 455 unsigned long fstop; 456 457 _enter(",%s", args); 458 459 if (!*args) 460 return -EINVAL; 461 462 fstop = simple_strtoul(args, &args, 10); 463 if (args[0] != '%' || args[1] != '\0') 464 return -EINVAL; 465 466 if (fstop >= cache->fcull_percent) 467 return cachefiles_daemon_range_error(cache, args); 468 469 cache->fstop_percent = fstop; 470 return 0; 471 } 472 473 /* 474 * Set the percentage of blocks at which to stop culling 475 * - command: "brun <N>%" 476 */ 477 static int cachefiles_daemon_brun(struct cachefiles_cache *cache, char *args) 478 { 479 unsigned long brun; 480 481 _enter(",%s", args); 482 483 if (!*args) 484 return -EINVAL; 485 486 brun = simple_strtoul(args, &args, 10); 487 if (args[0] != '%' || args[1] != '\0') 488 return -EINVAL; 489 490 if (brun <= cache->bcull_percent || brun >= 100) 491 return cachefiles_daemon_range_error(cache, args); 492 493 cache->brun_percent = brun; 494 return 0; 495 } 496 497 /* 498 * Set the percentage of blocks at which to start culling 499 * - command: "bcull <N>%" 500 */ 501 static int cachefiles_daemon_bcull(struct cachefiles_cache *cache, char *args) 502 { 503 unsigned long bcull; 504 505 _enter(",%s", args); 506 507 if (!*args) 508 return -EINVAL; 509 510 bcull = simple_strtoul(args, &args, 10); 511 if (args[0] != '%' || args[1] != '\0') 512 return -EINVAL; 513 514 if (bcull <= cache->bstop_percent || bcull >= cache->brun_percent) 515 return cachefiles_daemon_range_error(cache, args); 516 517 cache->bcull_percent = bcull; 518 return 0; 519 } 520 521 /* 522 * Set the percentage of blocks at which to stop allocating 523 * - command: "bstop <N>%" 524 */ 525 static int cachefiles_daemon_bstop(struct cachefiles_cache *cache, char *args) 526 { 527 unsigned long bstop; 528 529 _enter(",%s", args); 530 531 if (!*args) 532 return -EINVAL; 533 534 bstop = simple_strtoul(args, &args, 10); 535 if (args[0] != '%' || args[1] != '\0') 536 return -EINVAL; 537 538 if (bstop >= cache->bcull_percent) 539 return cachefiles_daemon_range_error(cache, args); 540 541 cache->bstop_percent = bstop; 542 return 0; 543 } 544 545 /* 546 * Set the cache directory 547 * - command: "dir <name>" 548 */ 549 static int cachefiles_daemon_dir(struct cachefiles_cache *cache, char *args) 550 { 551 char *dir; 552 553 _enter(",%s", args); 554 555 if (!*args) { 556 pr_err("Empty directory specified\n"); 557 return -EINVAL; 558 } 559 560 if (cache->rootdirname) { 561 pr_err("Second cache directory specified\n"); 562 return -EEXIST; 563 } 564 565 dir = kstrdup(args, GFP_KERNEL); 566 if (!dir) 567 return -ENOMEM; 568 569 cache->rootdirname = dir; 570 return 0; 571 } 572 573 /* 574 * Set the cache security context 575 * - command: "secctx <ctx>" 576 */ 577 static int cachefiles_daemon_secctx(struct cachefiles_cache *cache, char *args) 578 { 579 char *secctx; 580 581 _enter(",%s", args); 582 583 if (!*args) { 584 pr_err("Empty security context specified\n"); 585 return -EINVAL; 586 } 587 588 if (cache->secctx) { 589 pr_err("Second security context specified\n"); 590 return -EINVAL; 591 } 592 593 secctx = kstrdup(args, GFP_KERNEL); 594 if (!secctx) 595 return -ENOMEM; 596 597 cache->secctx = secctx; 598 return 0; 599 } 600 601 /* 602 * Set the cache tag 603 * - command: "tag <name>" 604 */ 605 static int cachefiles_daemon_tag(struct cachefiles_cache *cache, char *args) 606 { 607 char *tag; 608 609 _enter(",%s", args); 610 611 if (!*args) { 612 pr_err("Empty tag specified\n"); 613 return -EINVAL; 614 } 615 616 if (cache->tag) 617 return -EEXIST; 618 619 tag = kstrdup(args, GFP_KERNEL); 620 if (!tag) 621 return -ENOMEM; 622 623 cache->tag = tag; 624 return 0; 625 } 626 627 /* 628 * Request a node in the cache be culled from the current working directory 629 * - command: "cull <name>" 630 */ 631 static int cachefiles_daemon_cull(struct cachefiles_cache *cache, char *args) 632 { 633 struct path path; 634 const struct cred *saved_cred; 635 int ret; 636 637 _enter(",%s", args); 638 639 if (strchr(args, '/')) 640 goto inval; 641 642 if (!test_bit(CACHEFILES_READY, &cache->flags)) { 643 pr_err("cull applied to unready cache\n"); 644 return -EIO; 645 } 646 647 if (test_bit(CACHEFILES_DEAD, &cache->flags)) { 648 pr_err("cull applied to dead cache\n"); 649 return -EIO; 650 } 651 652 get_fs_pwd(current->fs, &path); 653 654 if (!d_can_lookup(path.dentry)) 655 goto notdir; 656 657 cachefiles_begin_secure(cache, &saved_cred); 658 ret = cachefiles_cull(cache, path.dentry, args); 659 cachefiles_end_secure(cache, saved_cred); 660 661 path_put(&path); 662 _leave(" = %d", ret); 663 return ret; 664 665 notdir: 666 path_put(&path); 667 pr_err("cull command requires dirfd to be a directory\n"); 668 return -ENOTDIR; 669 670 inval: 671 pr_err("cull command requires dirfd and filename\n"); 672 return -EINVAL; 673 } 674 675 /* 676 * Set debugging mode 677 * - command: "debug <mask>" 678 */ 679 static int cachefiles_daemon_debug(struct cachefiles_cache *cache, char *args) 680 { 681 unsigned long mask; 682 683 _enter(",%s", args); 684 685 mask = simple_strtoul(args, &args, 0); 686 if (args[0] != '\0') 687 goto inval; 688 689 cachefiles_debug = mask; 690 _leave(" = 0"); 691 return 0; 692 693 inval: 694 pr_err("debug command requires mask\n"); 695 return -EINVAL; 696 } 697 698 /* 699 * Find out whether an object in the current working directory is in use or not 700 * - command: "inuse <name>" 701 */ 702 static int cachefiles_daemon_inuse(struct cachefiles_cache *cache, char *args) 703 { 704 struct path path; 705 const struct cred *saved_cred; 706 int ret; 707 708 //_enter(",%s", args); 709 710 if (strchr(args, '/')) 711 goto inval; 712 713 if (!test_bit(CACHEFILES_READY, &cache->flags)) { 714 pr_err("inuse applied to unready cache\n"); 715 return -EIO; 716 } 717 718 if (test_bit(CACHEFILES_DEAD, &cache->flags)) { 719 pr_err("inuse applied to dead cache\n"); 720 return -EIO; 721 } 722 723 get_fs_pwd(current->fs, &path); 724 725 if (!d_can_lookup(path.dentry)) 726 goto notdir; 727 728 cachefiles_begin_secure(cache, &saved_cred); 729 ret = cachefiles_check_in_use(cache, path.dentry, args); 730 cachefiles_end_secure(cache, saved_cred); 731 732 path_put(&path); 733 //_leave(" = %d", ret); 734 return ret; 735 736 notdir: 737 path_put(&path); 738 pr_err("inuse command requires dirfd to be a directory\n"); 739 return -ENOTDIR; 740 741 inval: 742 pr_err("inuse command requires dirfd and filename\n"); 743 return -EINVAL; 744 } 745 746 /* 747 * Bind a directory as a cache 748 */ 749 static int cachefiles_daemon_bind(struct cachefiles_cache *cache, char *args) 750 { 751 _enter("{%u,%u,%u,%u,%u,%u},%s", 752 cache->frun_percent, 753 cache->fcull_percent, 754 cache->fstop_percent, 755 cache->brun_percent, 756 cache->bcull_percent, 757 cache->bstop_percent, 758 args); 759 760 if (cache->fstop_percent >= cache->fcull_percent || 761 cache->fcull_percent >= cache->frun_percent || 762 cache->frun_percent >= 100) 763 return -ERANGE; 764 765 if (cache->bstop_percent >= cache->bcull_percent || 766 cache->bcull_percent >= cache->brun_percent || 767 cache->brun_percent >= 100) 768 return -ERANGE; 769 770 if (!cache->rootdirname) { 771 pr_err("No cache directory specified\n"); 772 return -EINVAL; 773 } 774 775 /* Don't permit already bound caches to be re-bound */ 776 if (test_bit(CACHEFILES_READY, &cache->flags)) { 777 pr_err("Cache already bound\n"); 778 return -EBUSY; 779 } 780 781 if (IS_ENABLED(CONFIG_CACHEFILES_ONDEMAND)) { 782 if (!strcmp(args, "ondemand")) { 783 set_bit(CACHEFILES_ONDEMAND_MODE, &cache->flags); 784 } else if (*args) { 785 pr_err("Invalid argument to the 'bind' command\n"); 786 return -EINVAL; 787 } 788 } else if (*args) { 789 pr_err("'bind' command doesn't take an argument\n"); 790 return -EINVAL; 791 } 792 793 /* Make sure we have copies of the tag string */ 794 if (!cache->tag) { 795 /* 796 * The tag string is released by the fops->release() 797 * function, so we don't release it on error here 798 */ 799 cache->tag = kstrdup("CacheFiles", GFP_KERNEL); 800 if (!cache->tag) 801 return -ENOMEM; 802 } 803 804 return cachefiles_add_cache(cache); 805 } 806 807 /* 808 * Unbind a cache. 809 */ 810 static void cachefiles_daemon_unbind(struct cachefiles_cache *cache) 811 { 812 _enter(""); 813 814 if (test_bit(CACHEFILES_READY, &cache->flags)) 815 cachefiles_withdraw_cache(cache); 816 817 cachefiles_put_directory(cache->graveyard); 818 cachefiles_put_directory(cache->store); 819 mntput(cache->mnt); 820 put_cred(cache->cache_cred); 821 822 kfree(cache->rootdirname); 823 kfree(cache->secctx); 824 kfree(cache->tag); 825 826 _leave(""); 827 } 828
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