fs/9p/v9fs.c

   1 /*
   2  *  linux/fs/9p/v9fs.c
   3  *
   4  *  This file contains functions assisting in mapping VFS to 9P2000
   5  *
   6  *  Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
   7  *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License version 2
  11  *  as published by the Free Software Foundation.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to:
  20  *  Free Software Foundation
  21  *  51 Franklin Street, Fifth Floor
  22  *  Boston, MA  02111-1301  USA
  23  *
  24  */
  25
  26 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  27
  28 #include <linux/module.h>
  29 #include <linux/errno.h>
  30 #include <linux/fs.h>
  31 #include <linux/sched.h>
  32 #include <linux/parser.h>
  33 #include <linux/idr.h>
  34 #include <linux/slab.h>
  35 #include <net/9p/9p.h>
  36 #include <net/9p/client.h>
  37 #include <net/9p/transport.h>
  38 #include "v9fs.h"
  39 #include "v9fs_vfs.h"
  40 #include "cache.h"
  41
  42 static DEFINE_SPINLOCK(v9fs_sessionlist_lock);
  43 static LIST_HEAD(v9fs_sessionlist);
  44 struct kmem_cache *v9fs_inode_cache;
  45
  46 /*
  47  * Option Parsing (code inspired by NFS code)
  48  *  NOTE: each transport will parse its own options
  49  */
  50
  51 enum {
  52         /* Options that take integer arguments */
  53         Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid,
  54         /* String options */
  55         Opt_uname, Opt_remotename, Opt_cache, Opt_cachetag,
  56         /* Options that take no arguments */
  57         Opt_nodevmap,
  58         /* Cache options */
  59         Opt_cache_loose, Opt_fscache, Opt_mmap,
  60         /* Access options */
  61         Opt_access, Opt_posixacl,
  62         /* Lock timeout option */
  63         Opt_locktimeout,
  64         /* Error token */
  65         Opt_err
  66 };
  67
  68 static const match_table_t tokens = {
  69         {Opt_debug, "debug=%x"},
  70         {Opt_dfltuid, "dfltuid=%u"},
  71         {Opt_dfltgid, "dfltgid=%u"},
  72         {Opt_afid, "afid=%u"},
  73         {Opt_uname, "uname=%s"},
  74         {Opt_remotename, "aname=%s"},
  75         {Opt_nodevmap, "nodevmap"},
  76         {Opt_cache, "cache=%s"},
  77         {Opt_cache_loose, "loose"},
  78         {Opt_fscache, "fscache"},
  79         {Opt_mmap, "mmap"},
  80         {Opt_cachetag, "cachetag=%s"},
  81         {Opt_access, "access=%s"},
  82         {Opt_posixacl, "posixacl"},
  83         {Opt_locktimeout, "locktimeout=%u"},
  84         {Opt_err, NULL}
  85 };
  86
  87 /* Interpret mount options for cache mode */
  88 static int get_cache_mode(char *s)
  89 {
  90         int version = -EINVAL;
  91
  92         if (!strcmp(s, "loose")) {
  93                 version = CACHE_LOOSE;
  94                 p9_debug(P9_DEBUG_9P, "Cache mode: loose\n");
  95         } else if (!strcmp(s, "fscache")) {
  96                 version = CACHE_FSCACHE;
  97                 p9_debug(P9_DEBUG_9P, "Cache mode: fscache\n");
  98         } else if (!strcmp(s, "mmap")) {
  99                 version = CACHE_MMAP;
 100                 p9_debug(P9_DEBUG_9P, "Cache mode: mmap\n");
 101         } else if (!strcmp(s, "none")) {
 102                 version = CACHE_NONE;
 103                 p9_debug(P9_DEBUG_9P, "Cache mode: none\n");
 104         } else
 105                 pr_info("Unknown Cache mode %s\n", s);
 106         return version;
 107 }
 108
 109 /**
 110  * v9fs_parse_options - parse mount options into session structure
 111  * @v9ses: existing v9fs session information
 112  *
 113  * Return 0 upon success, -ERRNO upon failure.
 114  */
 115
 116 static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
 117 {
 118         char *options, *tmp_options;
 119         substring_t args[MAX_OPT_ARGS];
 120         char *p;
 121         int option = 0;
 122         char *s, *e;
 123         int ret = 0;
 124
 125         /* setup defaults */
 126         v9ses->afid = ~0;
 127         v9ses->debug = 0;
 128         v9ses->cache = CACHE_NONE;
 129 #ifdef CONFIG_9P_FSCACHE
 130         v9ses->cachetag = NULL;
 131 #endif
 132         v9ses->session_lock_timeout = P9_LOCK_TIMEOUT;
 133
 134         if (!opts)
 135                 return 0;
 136
 137         tmp_options = kstrdup(opts, GFP_KERNEL);
 138         if (!tmp_options) {
 139                 ret = -ENOMEM;
 140                 goto fail_option_alloc;
 141         }
 142         options = tmp_options;
 143
 144         while ((p = strsep(&options, ",")) != NULL) {
 145                 int token, r;
 146                 if (!*p)
 147                         continue;
 148                 token = match_token(p, tokens, args);
 149                 switch (token) {
 150                 case Opt_debug:
 151                         r = match_int(&args[0], &option);
 152                         if (r < 0) {
 153                                 p9_debug(P9_DEBUG_ERROR,
 154                                          "integer field, but no integer?\n");
 155                                 ret = r;
 156                                 continue;
 157                         }
 158                         v9ses->debug = option;
 159 #ifdef CONFIG_NET_9P_DEBUG
 160                         p9_debug_level = option;
 161 #endif
 162                         break;
 163
 164                 case Opt_dfltuid:
 165                         r = match_int(&args[0], &option);
 166                         if (r < 0) {
 167                                 p9_debug(P9_DEBUG_ERROR,
 168                                          "integer field, but no integer?\n");
 169                                 ret = r;
 170                                 continue;
 171                         }
 172                         v9ses->dfltuid = make_kuid(current_user_ns(), option);
 173                         if (!uid_valid(v9ses->dfltuid)) {
 174                                 p9_debug(P9_DEBUG_ERROR,
 175                                          "uid field, but not a uid?\n");
 176                                 ret = -EINVAL;
 177                                 continue;
 178                         }
 179                         break;
 180                 case Opt_dfltgid:
 181                         r = match_int(&args[0], &option);
 182                         if (r < 0) {
 183                                 p9_debug(P9_DEBUG_ERROR,
 184                                          "integer field, but no integer?\n");
 185                                 ret = r;
 186                                 continue;
 187                         }
 188                         v9ses->dfltgid = make_kgid(current_user_ns(), option);
 189                         if (!gid_valid(v9ses->dfltgid)) {
 190                                 p9_debug(P9_DEBUG_ERROR,
 191                                          "gid field, but not a gid?\n");
 192                                 ret = -EINVAL;
 193                                 continue;
 194                         }
 195                         break;
 196                 case Opt_afid:
 197                         r = match_int(&args[0], &option);
 198                         if (r < 0) {
 199                                 p9_debug(P9_DEBUG_ERROR,
 200                                          "integer field, but no integer?\n");
 201                                 ret = r;
 202                                 continue;
 203                         }
 204                         v9ses->afid = option;
 205                         break;
 206                 case Opt_uname:
 207                         kfree(v9ses->uname);
 208                         v9ses->uname = match_strdup(&args[0]);
 209                         if (!v9ses->uname) {
 210                                 ret = -ENOMEM;
 211                                 goto free_and_return;
 212                         }
 213                         break;
 214                 case Opt_remotename:
 215                         kfree(v9ses->aname);
 216                         v9ses->aname = match_strdup(&args[0]);
 217                         if (!v9ses->aname) {
 218                                 ret = -ENOMEM;
 219                                 goto free_and_return;
 220                         }
 221                         break;
 222                 case Opt_nodevmap:
 223                         v9ses->nodev = 1;
 224                         break;
 225                 case Opt_cache_loose:
 226                         v9ses->cache = CACHE_LOOSE;
 227                         break;
 228                 case Opt_fscache:
 229                         v9ses->cache = CACHE_FSCACHE;
 230                         break;
 231                 case Opt_mmap:
 232                         v9ses->cache = CACHE_MMAP;
 233                         break;
 234                 case Opt_cachetag:
 235 #ifdef CONFIG_9P_FSCACHE
 236                         v9ses->cachetag = match_strdup(&args[0]);
 237 #endif
 238                         break;
 239                 case Opt_cache:
 240                         s = match_strdup(&args[0]);
 241                         if (!s) {
 242                                 ret = -ENOMEM;
 243                                 p9_debug(P9_DEBUG_ERROR,
 244                                          "problem allocating copy of cache arg\n");
 245                                 goto free_and_return;
 246                         }
 247                         ret = get_cache_mode(s);
 248                         if (ret == -EINVAL) {
 249                                 kfree(s);
 250                                 goto free_and_return;
 251                         }
 252
 253                         v9ses->cache = ret;
 254                         kfree(s);
 255                         break;
 256
 257                 case Opt_access:
 258                         s = match_strdup(&args[0]);
 259                         if (!s) {
 260                                 ret = -ENOMEM;
 261                                 p9_debug(P9_DEBUG_ERROR,
 262                                          "problem allocating copy of access arg\n");
 263                                 goto free_and_return;
 264                         }
 265
 266                         v9ses->flags &= ~V9FS_ACCESS_MASK;
 267                         if (strcmp(s, "user") == 0)
 268                                 v9ses->flags |= V9FS_ACCESS_USER;
 269                         else if (strcmp(s, "any") == 0)
 270                                 v9ses->flags |= V9FS_ACCESS_ANY;
 271                         else if (strcmp(s, "client") == 0) {
 272                                 v9ses->flags |= V9FS_ACCESS_CLIENT;
 273                         } else {
 274                                 uid_t uid;
 275                                 v9ses->flags |= V9FS_ACCESS_SINGLE;
 276                                 uid = simple_strtoul(s, &e, 10);
 277                                 if (*e != '\0') {
 278                                         ret = -EINVAL;
 279                                         pr_info("Unknown access argument %s\n",
 280                                                 s);
 281                                         kfree(s);
 282                                         goto free_and_return;
 283                                 }
 284                                 v9ses->uid = make_kuid(current_user_ns(), uid);
 285                                 if (!uid_valid(v9ses->uid)) {
 286                                         ret = -EINVAL;
 287                                         pr_info("Uknown uid %s\n", s);
 288                                         kfree(s);
 289                                         goto free_and_return;
 290                                 }
 291                         }
 292
 293                         kfree(s);
 294                         break;
 295
 296                 case Opt_posixacl:
 297 #ifdef CONFIG_9P_FS_POSIX_ACL
 298                         v9ses->flags |= V9FS_POSIX_ACL;
 299 #else
 300                         p9_debug(P9_DEBUG_ERROR,
 301                                  "Not defined CONFIG_9P_FS_POSIX_ACL. Ignoring posixacl option\n");
 302 #endif
 303                         break;
 304
 305                 case Opt_locktimeout:
 306                         r = match_int(&args[0], &option);
 307                         if (r < 0) {
 308                                 p9_debug(P9_DEBUG_ERROR,
 309                                          "integer field, but no integer?\n");
 310                                 ret = r;
 311                                 continue;
 312                         }
 313                         if (option < 1) {
 314                                 p9_debug(P9_DEBUG_ERROR,
 315                                          "locktimeout must be a greater than zero integer.\n");
 316                                 ret = -EINVAL;
 317                                 continue;
 318                         }
 319                         v9ses->session_lock_timeout = (long)option * HZ;
 320                         break;
 321
 322                 default:
 323                         continue;
 324                 }
 325         }
 326
 327 free_and_return:
 328         kfree(tmp_options);
 329 fail_option_alloc:
 330         return ret;
 331 }
 332
 333 /**
 334  * v9fs_session_init - initialize session
 335  * @v9ses: session information structure
 336  * @dev_name: device being mounted
 337  * @data: options
 338  *
 339  */
 340
 341 struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
 342                   const char *dev_name, char *data)
 343 {
 344         struct p9_fid *fid;
 345         int rc = -ENOMEM;
 346
 347         v9ses->uname = kstrdup(V9FS_DEFUSER, GFP_KERNEL);
 348         if (!v9ses->uname)
 349                 goto err_names;
 350
 351         v9ses->aname = kstrdup(V9FS_DEFANAME, GFP_KERNEL);
 352         if (!v9ses->aname)
 353                 goto err_names;
 354         init_rwsem(&v9ses->rename_sem);
 355
 356         rc = bdi_setup_and_register(&v9ses->bdi, "9p");
 357         if (rc)
 358                 goto err_names;
 359
 360         v9ses->uid = INVALID_UID;
 361         v9ses->dfltuid = V9FS_DEFUID;
 362         v9ses->dfltgid = V9FS_DEFGID;
 363
 364         v9ses->clnt = p9_client_create(dev_name, data);
 365         if (IS_ERR(v9ses->clnt)) {
 366                 rc = PTR_ERR(v9ses->clnt);
 367                 p9_debug(P9_DEBUG_ERROR, "problem initializing 9p client\n");
 368                 goto err_bdi;
 369         }
 370
 371         v9ses->flags = V9FS_ACCESS_USER;
 372
 373         if (p9_is_proto_dotl(v9ses->clnt)) {
 374                 v9ses->flags = V9FS_ACCESS_CLIENT;
 375                 v9ses->flags |= V9FS_PROTO_2000L;
 376         } else if (p9_is_proto_dotu(v9ses->clnt)) {
 377                 v9ses->flags |= V9FS_PROTO_2000U;
 378         }
 379
 380         rc = v9fs_parse_options(v9ses, data);
 381         if (rc < 0)
 382                 goto err_clnt;
 383
 384         v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ;
 385
 386         if (!v9fs_proto_dotl(v9ses) &&
 387             ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
 388                 /*
 389                  * We support ACCESS_CLIENT only for dotl.
 390                  * Fall back to ACCESS_USER
 391                  */
 392                 v9ses->flags &= ~V9FS_ACCESS_MASK;
 393                 v9ses->flags |= V9FS_ACCESS_USER;
 394         }
 395         /*FIXME !! */
 396         /* for legacy mode, fall back to V9FS_ACCESS_ANY */
 397         if (!(v9fs_proto_dotu(v9ses) || v9fs_proto_dotl(v9ses)) &&
 398                 ((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) {
 399
 400                 v9ses->flags &= ~V9FS_ACCESS_MASK;
 401                 v9ses->flags |= V9FS_ACCESS_ANY;
 402                 v9ses->uid = INVALID_UID;
 403         }
 404         if (!v9fs_proto_dotl(v9ses) ||
 405                 !((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
 406                 /*
 407                  * We support ACL checks on clinet only if the protocol is
 408                  * 9P2000.L and access is V9FS_ACCESS_CLIENT.
 409                  */
 410                 v9ses->flags &= ~V9FS_ACL_MASK;
 411         }
 412
 413         fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, INVALID_UID,
 414                                                         v9ses->aname);
 415         if (IS_ERR(fid)) {
 416                 rc = PTR_ERR(fid);
 417                 p9_debug(P9_DEBUG_ERROR, "cannot attach\n");
 418                 goto err_clnt;
 419         }
 420
 421         if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE)
 422                 fid->uid = v9ses->uid;
 423         else
 424                 fid->uid = INVALID_UID;
 425
 426 #ifdef CONFIG_9P_FSCACHE
 427         /* register the session for caching */
 428         v9fs_cache_session_get_cookie(v9ses);
 429 #endif
 430         spin_lock(&v9fs_sessionlist_lock);
 431         list_add(&v9ses->slist, &v9fs_sessionlist);
 432         spin_unlock(&v9fs_sessionlist_lock);
 433
 434         return fid;
 435
 436 err_clnt:
 437         p9_client_destroy(v9ses->clnt);
 438 err_bdi:
 439         bdi_destroy(&v9ses->bdi);
 440 err_names:
 441         kfree(v9ses->uname);
 442         kfree(v9ses->aname);
 443         return ERR_PTR(rc);
 444 }
 445
 446 /**
 447  * v9fs_session_close - shutdown a session
 448  * @v9ses: session information structure
 449  *
 450  */
 451
 452 void v9fs_session_close(struct v9fs_session_info *v9ses)
 453 {
 454         if (v9ses->clnt) {
 455                 p9_client_destroy(v9ses->clnt);
 456                 v9ses->clnt = NULL;
 457         }
 458
 459 #ifdef CONFIG_9P_FSCACHE
 460         if (v9ses->fscache)
 461                 v9fs_cache_session_put_cookie(v9ses);
 462         kfree(v9ses->cachetag);
 463 #endif
 464         kfree(v9ses->uname);
 465         kfree(v9ses->aname);
 466
 467         bdi_destroy(&v9ses->bdi);
 468
 469         spin_lock(&v9fs_sessionlist_lock);
 470         list_del(&v9ses->slist);
 471         spin_unlock(&v9fs_sessionlist_lock);
 472 }
 473
 474 /**
 475  * v9fs_session_cancel - terminate a session
 476  * @v9ses: session to terminate
 477  *
 478  * mark transport as disconnected and cancel all pending requests.
 479  */
 480
 481 void v9fs_session_cancel(struct v9fs_session_info *v9ses) {
 482         p9_debug(P9_DEBUG_ERROR, "cancel session %p\n", v9ses);
 483         p9_client_disconnect(v9ses->clnt);
 484 }
 485
 486 /**
 487  * v9fs_session_begin_cancel - Begin terminate of a session
 488  * @v9ses: session to terminate
 489  *
 490  * After this call we don't allow any request other than clunk.
 491  */
 492
 493 void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses)
 494 {
 495         p9_debug(P9_DEBUG_ERROR, "begin cancel session %p\n", v9ses);
 496         p9_client_begin_disconnect(v9ses->clnt);
 497 }
 498
 499 extern int v9fs_error_init(void);
 500
 501 static struct kobject *v9fs_kobj;
 502
 503 #ifdef CONFIG_9P_FSCACHE
 504 /**
 505  * caches_show - list caches associated with a session
 506  *
 507  * Returns the size of buffer written.
 508  */
 509
 510 static ssize_t caches_show(struct kobject *kobj,
 511                            struct kobj_attribute *attr,
 512                            char *buf)
 513 {
 514         ssize_t n = 0, count = 0, limit = PAGE_SIZE;
 515         struct v9fs_session_info *v9ses;
 516
 517         spin_lock(&v9fs_sessionlist_lock);
 518         list_for_each_entry(v9ses, &v9fs_sessionlist, slist) {
 519                 if (v9ses->cachetag) {
 520                         n = snprintf(buf, limit, "%s\n", v9ses->cachetag);
 521                         if (n < 0) {
 522                                 count = n;
 523                                 break;
 524                         }
 525
 526                         count += n;
 527                         limit -= n;
 528                 }
 529         }
 530
 531         spin_unlock(&v9fs_sessionlist_lock);
 532         return count;
 533 }
 534
 535 static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches);
 536 #endif /* CONFIG_9P_FSCACHE */
 537
 538 static struct attribute *v9fs_attrs[] = {
 539 #ifdef CONFIG_9P_FSCACHE
 540         &v9fs_attr_cache.attr,
 541 #endif
 542         NULL,
 543 };
 544
 545 static struct attribute_group v9fs_attr_group = {
 546         .attrs = v9fs_attrs,
 547 };
 548
 549 /**
 550  * v9fs_sysfs_init - Initialize the v9fs sysfs interface
 551  *
 552  */
 553
 554 static int __init v9fs_sysfs_init(void)
 555 {
 556         v9fs_kobj = kobject_create_and_add("9p", fs_kobj);
 557         if (!v9fs_kobj)
 558                 return -ENOMEM;
 559
 560         if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) {
 561                 kobject_put(v9fs_kobj);
 562                 return -ENOMEM;
 563         }
 564
 565         return 0;
 566 }
 567
 568 /**
 569  * v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface
 570  *
 571  */
 572
 573 static void v9fs_sysfs_cleanup(void)
 574 {
 575         sysfs_remove_group(v9fs_kobj, &v9fs_attr_group);
 576         kobject_put(v9fs_kobj);
 577 }
 578
 579 static void v9fs_inode_init_once(void *foo)
 580 {
 581         struct v9fs_inode *v9inode = (struct v9fs_inode *)foo;
 582 #ifdef CONFIG_9P_FSCACHE
 583         v9inode->fscache = NULL;
 584 #endif
 585         memset(&v9inode->qid, 0, sizeof(v9inode->qid));
 586         inode_init_once(&v9inode->vfs_inode);
 587 }
 588
 589 /**
 590  * v9fs_init_inode_cache - initialize a cache for 9P
 591  * Returns 0 on success.
 592  */
 593 static int v9fs_init_inode_cache(void)
 594 {
 595         v9fs_inode_cache = kmem_cache_create("v9fs_inode_cache",
 596                                           sizeof(struct v9fs_inode),
 597                                           0, (SLAB_RECLAIM_ACCOUNT|
 598                                               SLAB_MEM_SPREAD|SLAB_ACCOUNT),
 599                                           v9fs_inode_init_once);
 600         if (!v9fs_inode_cache)
 601                 return -ENOMEM;
 602
 603         return 0;
 604 }
 605
 606 /**
 607  * v9fs_destroy_inode_cache - destroy the cache of 9P inode
 608  *
 609  */
 610 static void v9fs_destroy_inode_cache(void)
 611 {
 612         /*
 613          * Make sure all delayed rcu free inodes are flushed before we
 614          * destroy cache.
 615          */
 616         rcu_barrier();
 617         kmem_cache_destroy(v9fs_inode_cache);
 618 }
 619
 620 static int v9fs_cache_register(void)
 621 {
 622         int ret;
 623         ret = v9fs_init_inode_cache();
 624         if (ret < 0)
 625                 return ret;
 626 #ifdef CONFIG_9P_FSCACHE
 627         ret = fscache_register_netfs(&v9fs_cache_netfs);
 628         if (ret < 0)
 629                 v9fs_destroy_inode_cache();
 630 #endif
 631         return ret;
 632 }
 633
 634 static void v9fs_cache_unregister(void)
 635 {
 636         v9fs_destroy_inode_cache();
 637 #ifdef CONFIG_9P_FSCACHE
 638         fscache_unregister_netfs(&v9fs_cache_netfs);
 639 #endif
 640 }
 641
 642 /**
 643  * init_v9fs - Initialize module
 644  *
 645  */
 646
 647 static int __init init_v9fs(void)
 648 {
 649         int err;
 650         pr_info("Installing v9fs 9p2000 file system support\n");
 651         /* TODO: Setup list of registered trasnport modules */
 652
 653         err = v9fs_cache_register();
 654         if (err < 0) {
 655                 pr_err("Failed to register v9fs for caching\n");
 656                 return err;
 657         }
 658
 659         err = v9fs_sysfs_init();
 660         if (err < 0) {
 661                 pr_err("Failed to register with sysfs\n");
 662                 goto out_cache;
 663         }
 664         err = register_filesystem(&v9fs_fs_type);
 665         if (err < 0) {
 666                 pr_err("Failed to register filesystem\n");
 667                 goto out_sysfs_cleanup;
 668         }
 669
 670         return 0;
 671
 672 out_sysfs_cleanup:
 673         v9fs_sysfs_cleanup();
 674
 675 out_cache:
 676         v9fs_cache_unregister();
 677
 678         return err;
 679 }
 680
 681 /**
 682  * exit_v9fs - shutdown module
 683  *
 684  */
 685
 686 static void __exit exit_v9fs(void)
 687 {
 688         v9fs_sysfs_cleanup();
 689         v9fs_cache_unregister();
 690         unregister_filesystem(&v9fs_fs_type);
 691 }
 692
 693 module_init(init_v9fs)
 694 module_exit(exit_v9fs)
 695
 696 MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>");
 697 MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
 698 MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>");
 699 MODULE_LICENSE("GPL");