git.oblomov.eu Git - linux-2.6/blob - fs/fuse/inode.c

   1 /*
   2   FUSE: Filesystem in Userspace
   3   Copyright (C) 2001-2005  Miklos Szeredi <miklos@szeredi.hu>
   4
   5   This program can be distributed under the terms of the GNU GPL.
   6   See the file COPYING.
   7 */
   8
   9 #include "fuse_i.h"
  10
  11 #include <linux/pagemap.h>
  12 #include <linux/slab.h>
  13 #include <linux/file.h>
  14 #include <linux/mount.h>
  15 #include <linux/seq_file.h>
  16 #include <linux/init.h>
  17 #include <linux/module.h>
  18 #include <linux/parser.h>
  19 #include <linux/statfs.h>
  20
  21 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
  22 MODULE_DESCRIPTION("Filesystem in Userspace");
  23 MODULE_LICENSE("GPL");
  24
  25 spinlock_t fuse_lock;
  26 static kmem_cache_t *fuse_inode_cachep;
  27 static struct subsystem connections_subsys;
  28
  29 struct fuse_conn_attr {
  30         struct attribute attr;
  31         ssize_t (*show)(struct fuse_conn *, char *);
  32         ssize_t (*store)(struct fuse_conn *, const char *, size_t);
  33 };
  34
  35 #define FUSE_SUPER_MAGIC 0x65735546
  36
  37 struct fuse_mount_data {
  38         int fd;
  39         unsigned rootmode;
  40         unsigned user_id;
  41         unsigned group_id;
  42         unsigned fd_present : 1;
  43         unsigned rootmode_present : 1;
  44         unsigned user_id_present : 1;
  45         unsigned group_id_present : 1;
  46         unsigned flags;
  47         unsigned max_read;
  48 };
  49
  50 static struct inode *fuse_alloc_inode(struct super_block *sb)
  51 {
  52         struct inode *inode;
  53         struct fuse_inode *fi;
  54
  55         inode = kmem_cache_alloc(fuse_inode_cachep, SLAB_KERNEL);
  56         if (!inode)
  57                 return NULL;
  58
  59         fi = get_fuse_inode(inode);
  60         fi->i_time = jiffies - 1;
  61         fi->nodeid = 0;
  62         fi->nlookup = 0;
  63         fi->forget_req = fuse_request_alloc();
  64         if (!fi->forget_req) {
  65                 kmem_cache_free(fuse_inode_cachep, inode);
  66                 return NULL;
  67         }
  68
  69         return inode;
  70 }
  71
  72 static void fuse_destroy_inode(struct inode *inode)
  73 {
  74         struct fuse_inode *fi = get_fuse_inode(inode);
  75         if (fi->forget_req)
  76                 fuse_request_free(fi->forget_req);
  77         kmem_cache_free(fuse_inode_cachep, inode);
  78 }
  79
  80 static void fuse_read_inode(struct inode *inode)
  81 {
  82         /* No op */
  83 }
  84
  85 void fuse_send_forget(struct fuse_conn *fc, struct fuse_req *req,
  86                       unsigned long nodeid, u64 nlookup)
  87 {
  88         struct fuse_forget_in *inarg = &req->misc.forget_in;
  89         inarg->nlookup = nlookup;
  90         req->in.h.opcode = FUSE_FORGET;
  91         req->in.h.nodeid = nodeid;
  92         req->in.numargs = 1;
  93         req->in.args[0].size = sizeof(struct fuse_forget_in);
  94         req->in.args[0].value = inarg;
  95         request_send_noreply(fc, req);
  96 }
  97
  98 static void fuse_clear_inode(struct inode *inode)
  99 {
 100         if (inode->i_sb->s_flags & MS_ACTIVE) {
 101                 struct fuse_conn *fc = get_fuse_conn(inode);
 102                 struct fuse_inode *fi = get_fuse_inode(inode);
 103                 fuse_send_forget(fc, fi->forget_req, fi->nodeid, fi->nlookup);
 104                 fi->forget_req = NULL;
 105         }
 106 }
 107
 108 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr)
 109 {
 110         if (S_ISREG(inode->i_mode) && i_size_read(inode) != attr->size)
 111                 invalidate_inode_pages(inode->i_mapping);
 112
 113         inode->i_ino     = attr->ino;
 114         inode->i_mode    = (inode->i_mode & S_IFMT) + (attr->mode & 07777);
 115         inode->i_nlink   = attr->nlink;
 116         inode->i_uid     = attr->uid;
 117         inode->i_gid     = attr->gid;
 118         i_size_write(inode, attr->size);
 119         inode->i_blksize = PAGE_CACHE_SIZE;
 120         inode->i_blocks  = attr->blocks;
 121         inode->i_atime.tv_sec   = attr->atime;
 122         inode->i_atime.tv_nsec  = attr->atimensec;
 123         inode->i_mtime.tv_sec   = attr->mtime;
 124         inode->i_mtime.tv_nsec  = attr->mtimensec;
 125         inode->i_ctime.tv_sec   = attr->ctime;
 126         inode->i_ctime.tv_nsec  = attr->ctimensec;
 127 }
 128
 129 static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
 130 {
 131         inode->i_mode = attr->mode & S_IFMT;
 132         i_size_write(inode, attr->size);
 133         if (S_ISREG(inode->i_mode)) {
 134                 fuse_init_common(inode);
 135                 fuse_init_file_inode(inode);
 136         } else if (S_ISDIR(inode->i_mode))
 137                 fuse_init_dir(inode);
 138         else if (S_ISLNK(inode->i_mode))
 139                 fuse_init_symlink(inode);
 140         else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
 141                  S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
 142                 fuse_init_common(inode);
 143                 init_special_inode(inode, inode->i_mode,
 144                                    new_decode_dev(attr->rdev));
 145         } else
 146                 BUG();
 147 }
 148
 149 static int fuse_inode_eq(struct inode *inode, void *_nodeidp)
 150 {
 151         unsigned long nodeid = *(unsigned long *) _nodeidp;
 152         if (get_node_id(inode) == nodeid)
 153                 return 1;
 154         else
 155                 return 0;
 156 }
 157
 158 static int fuse_inode_set(struct inode *inode, void *_nodeidp)
 159 {
 160         unsigned long nodeid = *(unsigned long *) _nodeidp;
 161         get_fuse_inode(inode)->nodeid = nodeid;
 162         return 0;
 163 }
 164
 165 struct inode *fuse_iget(struct super_block *sb, unsigned long nodeid,
 166                         int generation, struct fuse_attr *attr)
 167 {
 168         struct inode *inode;
 169         struct fuse_inode *fi;
 170         struct fuse_conn *fc = get_fuse_conn_super(sb);
 171         int retried = 0;
 172
 173  retry:
 174         inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
 175         if (!inode)
 176                 return NULL;
 177
 178         if ((inode->i_state & I_NEW)) {
 179                 inode->i_flags |= S_NOATIME|S_NOCMTIME;
 180                 inode->i_generation = generation;
 181                 inode->i_data.backing_dev_info = &fc->bdi;
 182                 fuse_init_inode(inode, attr);
 183                 unlock_new_inode(inode);
 184         } else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
 185                 BUG_ON(retried);
 186                 /* Inode has changed type, any I/O on the old should fail */
 187                 make_bad_inode(inode);
 188                 iput(inode);
 189                 retried = 1;
 190                 goto retry;
 191         }
 192
 193         fi = get_fuse_inode(inode);
 194         fi->nlookup ++;
 195         fuse_change_attributes(inode, attr);
 196         return inode;
 197 }
 198
 199 static void fuse_put_super(struct super_block *sb)
 200 {
 201         struct fuse_conn *fc = get_fuse_conn_super(sb);
 202
 203         down_write(&fc->sbput_sem);
 204         while (!list_empty(&fc->background))
 205                 fuse_release_background(list_entry(fc->background.next,
 206                                                    struct fuse_req, bg_entry));
 207
 208         spin_lock(&fuse_lock);
 209         fc->mounted = 0;
 210         fc->connected = 0;
 211         spin_unlock(&fuse_lock);
 212         up_write(&fc->sbput_sem);
 213         /* Flush all readers on this fs */
 214         wake_up_all(&fc->waitq);
 215         kobject_del(&fc->kobj);
 216         kobject_put(&fc->kobj);
 217 }
 218
 219 static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
 220 {
 221         stbuf->f_type    = FUSE_SUPER_MAGIC;
 222         stbuf->f_bsize   = attr->bsize;
 223         stbuf->f_frsize  = attr->frsize;
 224         stbuf->f_blocks  = attr->blocks;
 225         stbuf->f_bfree   = attr->bfree;
 226         stbuf->f_bavail  = attr->bavail;
 227         stbuf->f_files   = attr->files;
 228         stbuf->f_ffree   = attr->ffree;
 229         stbuf->f_namelen = attr->namelen;
 230         /* fsid is left zero */
 231 }
 232
 233 static int fuse_statfs(struct super_block *sb, struct kstatfs *buf)
 234 {
 235         struct fuse_conn *fc = get_fuse_conn_super(sb);
 236         struct fuse_req *req;
 237         struct fuse_statfs_out outarg;
 238         int err;
 239
 240         req = fuse_get_request(fc);
 241         if (!req)
 242                 return -EINTR;
 243
 244         memset(&outarg, 0, sizeof(outarg));
 245         req->in.numargs = 0;
 246         req->in.h.opcode = FUSE_STATFS;
 247         req->out.numargs = 1;
 248         req->out.args[0].size =
 249                 fc->minor < 4 ? FUSE_COMPAT_STATFS_SIZE : sizeof(outarg);
 250         req->out.args[0].value = &outarg;
 251         request_send(fc, req);
 252         err = req->out.h.error;
 253         if (!err)
 254                 convert_fuse_statfs(buf, &outarg.st);
 255         fuse_put_request(fc, req);
 256         return err;
 257 }
 258
 259 enum {
 260         OPT_FD,
 261         OPT_ROOTMODE,
 262         OPT_USER_ID,
 263         OPT_GROUP_ID,
 264         OPT_DEFAULT_PERMISSIONS,
 265         OPT_ALLOW_OTHER,
 266         OPT_MAX_READ,
 267         OPT_ERR
 268 };
 269
 270 static match_table_t tokens = {
 271         {OPT_FD,                        "fd=%u"},
 272         {OPT_ROOTMODE,                  "rootmode=%o"},
 273         {OPT_USER_ID,                   "user_id=%u"},
 274         {OPT_GROUP_ID,                  "group_id=%u"},
 275         {OPT_DEFAULT_PERMISSIONS,       "default_permissions"},
 276         {OPT_ALLOW_OTHER,               "allow_other"},
 277         {OPT_MAX_READ,                  "max_read=%u"},
 278         {OPT_ERR,                       NULL}
 279 };
 280
 281 static int parse_fuse_opt(char *opt, struct fuse_mount_data *d)
 282 {
 283         char *p;
 284         memset(d, 0, sizeof(struct fuse_mount_data));
 285         d->max_read = ~0;
 286
 287         while ((p = strsep(&opt, ",")) != NULL) {
 288                 int token;
 289                 int value;
 290                 substring_t args[MAX_OPT_ARGS];
 291                 if (!*p)
 292                         continue;
 293
 294                 token = match_token(p, tokens, args);
 295                 switch (token) {
 296                 case OPT_FD:
 297                         if (match_int(&args[0], &value))
 298                                 return 0;
 299                         d->fd = value;
 300                         d->fd_present = 1;
 301                         break;
 302
 303                 case OPT_ROOTMODE:
 304                         if (match_octal(&args[0], &value))
 305                                 return 0;
 306                         d->rootmode = value;
 307                         d->rootmode_present = 1;
 308                         break;
 309
 310                 case OPT_USER_ID:
 311                         if (match_int(&args[0], &value))
 312                                 return 0;
 313                         d->user_id = value;
 314                         d->user_id_present = 1;
 315                         break;
 316
 317                 case OPT_GROUP_ID:
 318                         if (match_int(&args[0], &value))
 319                                 return 0;
 320                         d->group_id = value;
 321                         d->group_id_present = 1;
 322                         break;
 323
 324                 case OPT_DEFAULT_PERMISSIONS:
 325                         d->flags |= FUSE_DEFAULT_PERMISSIONS;
 326                         break;
 327
 328                 case OPT_ALLOW_OTHER:
 329                         d->flags |= FUSE_ALLOW_OTHER;
 330                         break;
 331
 332                 case OPT_MAX_READ:
 333                         if (match_int(&args[0], &value))
 334                                 return 0;
 335                         d->max_read = value;
 336                         break;
 337
 338                 default:
 339                         return 0;
 340                 }
 341         }
 342
 343         if (!d->fd_present || !d->rootmode_present ||
 344             !d->user_id_present || !d->group_id_present)
 345                 return 0;
 346
 347         return 1;
 348 }
 349
 350 static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt)
 351 {
 352         struct fuse_conn *fc = get_fuse_conn_super(mnt->mnt_sb);
 353
 354         seq_printf(m, ",user_id=%u", fc->user_id);
 355         seq_printf(m, ",group_id=%u", fc->group_id);
 356         if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
 357                 seq_puts(m, ",default_permissions");
 358         if (fc->flags & FUSE_ALLOW_OTHER)
 359                 seq_puts(m, ",allow_other");
 360         if (fc->max_read != ~0)
 361                 seq_printf(m, ",max_read=%u", fc->max_read);
 362         return 0;
 363 }
 364
 365 static void fuse_conn_release(struct kobject *kobj)
 366 {
 367         struct fuse_conn *fc = get_fuse_conn_kobj(kobj);
 368
 369         while (!list_empty(&fc->unused_list)) {
 370                 struct fuse_req *req;
 371                 req = list_entry(fc->unused_list.next, struct fuse_req, list);
 372                 list_del(&req->list);
 373                 fuse_request_free(req);
 374         }
 375         kfree(fc);
 376 }
 377
 378 static struct fuse_conn *new_conn(void)
 379 {
 380         struct fuse_conn *fc;
 381
 382         fc = kzalloc(sizeof(*fc), GFP_KERNEL);
 383         if (fc) {
 384                 int i;
 385                 init_waitqueue_head(&fc->waitq);
 386                 INIT_LIST_HEAD(&fc->pending);
 387                 INIT_LIST_HEAD(&fc->processing);
 388                 INIT_LIST_HEAD(&fc->io);
 389                 INIT_LIST_HEAD(&fc->unused_list);
 390                 INIT_LIST_HEAD(&fc->background);
 391                 sema_init(&fc->outstanding_sem, 1); /* One for INIT */
 392                 init_rwsem(&fc->sbput_sem);
 393                 kobj_set_kset_s(fc, connections_subsys);
 394                 kobject_init(&fc->kobj);
 395                 for (i = 0; i < FUSE_MAX_OUTSTANDING; i++) {
 396                         struct fuse_req *req = fuse_request_alloc();
 397                         if (!req) {
 398                                 kobject_put(&fc->kobj);
 399                                 return NULL;
 400                         }
 401                         list_add(&req->list, &fc->unused_list);
 402                 }
 403                 fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
 404                 fc->bdi.unplug_io_fn = default_unplug_io_fn;
 405                 fc->reqctr = 0;
 406         }
 407         return fc;
 408 }
 409
 410 static struct fuse_conn *get_conn(struct file *file, struct super_block *sb)
 411 {
 412         struct fuse_conn *fc;
 413         int err;
 414
 415         err = -EINVAL;
 416         if (file->f_op != &fuse_dev_operations)
 417                 goto out_err;
 418
 419         err = -ENOMEM;
 420         fc = new_conn();
 421         if (!fc)
 422                 goto out_err;
 423
 424         spin_lock(&fuse_lock);
 425         err = -EINVAL;
 426         if (file->private_data)
 427                 goto out_unlock;
 428
 429         kobject_get(&fc->kobj);
 430         file->private_data = fc;
 431         spin_unlock(&fuse_lock);
 432         return fc;
 433
 434  out_unlock:
 435         spin_unlock(&fuse_lock);
 436         kobject_put(&fc->kobj);
 437  out_err:
 438         return ERR_PTR(err);
 439 }
 440
 441 static struct inode *get_root_inode(struct super_block *sb, unsigned mode)
 442 {
 443         struct fuse_attr attr;
 444         memset(&attr, 0, sizeof(attr));
 445
 446         attr.mode = mode;
 447         attr.ino = FUSE_ROOT_ID;
 448         return fuse_iget(sb, 1, 0, &attr);
 449 }
 450
 451 static struct super_operations fuse_super_operations = {
 452         .alloc_inode    = fuse_alloc_inode,
 453         .destroy_inode  = fuse_destroy_inode,
 454         .read_inode     = fuse_read_inode,
 455         .clear_inode    = fuse_clear_inode,
 456         .put_super      = fuse_put_super,
 457         .statfs         = fuse_statfs,
 458         .show_options   = fuse_show_options,
 459 };
 460
 461 static unsigned long long conn_id(void)
 462 {
 463         static unsigned long long ctr = 1;
 464         unsigned long long val;
 465         spin_lock(&fuse_lock);
 466         val = ctr++;
 467         spin_unlock(&fuse_lock);
 468         return val;
 469 }
 470
 471 static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 472 {
 473         struct fuse_conn *fc;
 474         struct inode *root;
 475         struct fuse_mount_data d;
 476         struct file *file;
 477         struct dentry *root_dentry;
 478         int err;
 479
 480         if (!parse_fuse_opt((char *) data, &d))
 481                 return -EINVAL;
 482
 483         sb->s_blocksize = PAGE_CACHE_SIZE;
 484         sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
 485         sb->s_magic = FUSE_SUPER_MAGIC;
 486         sb->s_op = &fuse_super_operations;
 487         sb->s_maxbytes = MAX_LFS_FILESIZE;
 488
 489         file = fget(d.fd);
 490         if (!file)
 491                 return -EINVAL;
 492
 493         fc = get_conn(file, sb);
 494         fput(file);
 495         if (IS_ERR(fc))
 496                 return PTR_ERR(fc);
 497
 498         fc->flags = d.flags;
 499         fc->user_id = d.user_id;
 500         fc->group_id = d.group_id;
 501         fc->max_read = d.max_read;
 502         if (fc->max_read / PAGE_CACHE_SIZE < fc->bdi.ra_pages)
 503                 fc->bdi.ra_pages = fc->max_read / PAGE_CACHE_SIZE;
 504
 505         /* Used by get_root_inode() */
 506         sb->s_fs_info = fc;
 507
 508         err = -ENOMEM;
 509         root = get_root_inode(sb, d.rootmode);
 510         if (!root)
 511                 goto err;
 512
 513         root_dentry = d_alloc_root(root);
 514         if (!root_dentry) {
 515                 iput(root);
 516                 goto err;
 517         }
 518
 519         err = kobject_set_name(&fc->kobj, "%llu", conn_id());
 520         if (err)
 521                 goto err_put_root;
 522
 523         err = kobject_add(&fc->kobj);
 524         if (err)
 525                 goto err_put_root;
 526
 527         sb->s_root = root_dentry;
 528         spin_lock(&fuse_lock);
 529         fc->mounted = 1;
 530         fc->connected = 1;
 531         spin_unlock(&fuse_lock);
 532
 533         fuse_send_init(fc);
 534
 535         return 0;
 536
 537  err_put_root:
 538         dput(root_dentry);
 539  err:
 540         kobject_put(&fc->kobj);
 541         return err;
 542 }
 543
 544 static struct super_block *fuse_get_sb(struct file_system_type *fs_type,
 545                                        int flags, const char *dev_name,
 546                                        void *raw_data)
 547 {
 548         return get_sb_nodev(fs_type, flags, raw_data, fuse_fill_super);
 549 }
 550
 551 static struct file_system_type fuse_fs_type = {
 552         .owner          = THIS_MODULE,
 553         .name           = "fuse",
 554         .get_sb         = fuse_get_sb,
 555         .kill_sb        = kill_anon_super,
 556 };
 557
 558 static ssize_t fuse_conn_waiting_show(struct fuse_conn *fc, char *page)
 559 {
 560         return sprintf(page, "%i\n", atomic_read(&fc->num_waiting));
 561 }
 562
 563 static struct fuse_conn_attr fuse_conn_waiting =
 564         __ATTR(waiting, 0400, fuse_conn_waiting_show, NULL);
 565
 566 static struct attribute *fuse_conn_attrs[] = {
 567         &fuse_conn_waiting.attr,
 568         NULL,
 569 };
 570
 571 static ssize_t fuse_conn_attr_show(struct kobject *kobj,
 572                                    struct attribute *attr,
 573                                    char *page)
 574 {
 575         struct fuse_conn_attr *fca =
 576                 container_of(attr, struct fuse_conn_attr, attr);
 577
 578         if (fca->show)
 579                 return fca->show(get_fuse_conn_kobj(kobj), page);
 580         else
 581                 return -EACCES;
 582 }
 583
 584 static ssize_t fuse_conn_attr_store(struct kobject *kobj,
 585                                     struct attribute *attr,
 586                                     const char *page, size_t count)
 587 {
 588         struct fuse_conn_attr *fca =
 589                 container_of(attr, struct fuse_conn_attr, attr);
 590
 591         if (fca->store)
 592                 return fca->store(get_fuse_conn_kobj(kobj), page, count);
 593         else
 594                 return -EACCES;
 595 }
 596
 597 static struct sysfs_ops fuse_conn_sysfs_ops = {
 598         .show   = &fuse_conn_attr_show,
 599         .store  = &fuse_conn_attr_store,
 600 };
 601
 602 static struct kobj_type ktype_fuse_conn = {
 603         .release        = fuse_conn_release,
 604         .sysfs_ops      = &fuse_conn_sysfs_ops,
 605         .default_attrs  = fuse_conn_attrs,
 606 };
 607
 608 static decl_subsys(fuse, NULL, NULL);
 609 static decl_subsys(connections, &ktype_fuse_conn, NULL);
 610
 611 static void fuse_inode_init_once(void *foo, kmem_cache_t *cachep,
 612                                  unsigned long flags)
 613 {
 614         struct inode * inode = foo;
 615
 616         if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
 617             SLAB_CTOR_CONSTRUCTOR)
 618                 inode_init_once(inode);
 619 }
 620
 621 static int __init fuse_fs_init(void)
 622 {
 623         int err;
 624
 625         err = register_filesystem(&fuse_fs_type);
 626         if (err)
 627                 printk("fuse: failed to register filesystem\n");
 628         else {
 629                 fuse_inode_cachep = kmem_cache_create("fuse_inode",
 630                                                       sizeof(struct fuse_inode),
 631                                                       0, SLAB_HWCACHE_ALIGN,
 632                                                       fuse_inode_init_once, NULL);
 633                 if (!fuse_inode_cachep) {
 634                         unregister_filesystem(&fuse_fs_type);
 635                         err = -ENOMEM;
 636                 }
 637         }
 638
 639         return err;
 640 }
 641
 642 static void fuse_fs_cleanup(void)
 643 {
 644         unregister_filesystem(&fuse_fs_type);
 645         kmem_cache_destroy(fuse_inode_cachep);
 646 }
 647
 648 static int fuse_sysfs_init(void)
 649 {
 650         int err;
 651
 652         kset_set_kset_s(&fuse_subsys, fs_subsys);
 653         err = subsystem_register(&fuse_subsys);
 654         if (err)
 655                 goto out_err;
 656
 657         kset_set_kset_s(&connections_subsys, fuse_subsys);
 658         err = subsystem_register(&connections_subsys);
 659         if (err)
 660                 goto out_fuse_unregister;
 661
 662         return 0;
 663
 664  out_fuse_unregister:
 665         subsystem_unregister(&fuse_subsys);
 666  out_err:
 667         return err;
 668 }
 669
 670 static void fuse_sysfs_cleanup(void)
 671 {
 672         subsystem_unregister(&connections_subsys);
 673         subsystem_unregister(&fuse_subsys);
 674 }
 675
 676 static int __init fuse_init(void)
 677 {
 678         int res;
 679
 680         printk("fuse init (API version %i.%i)\n",
 681                FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
 682
 683         spin_lock_init(&fuse_lock);
 684         res = fuse_fs_init();
 685         if (res)
 686                 goto err;
 687
 688         res = fuse_dev_init();
 689         if (res)
 690                 goto err_fs_cleanup;
 691
 692         res = fuse_sysfs_init();
 693         if (res)
 694                 goto err_dev_cleanup;
 695
 696         return 0;
 697
 698  err_dev_cleanup:
 699         fuse_dev_cleanup();
 700  err_fs_cleanup:
 701         fuse_fs_cleanup();
 702  err:
 703         return res;
 704 }
 705
 706 static void __exit fuse_exit(void)
 707 {
 708         printk(KERN_DEBUG "fuse exit\n");
 709
 710         fuse_sysfs_cleanup();
 711         fuse_fs_cleanup();
 712         fuse_dev_cleanup();
 713 }
 714
 715 module_init(fuse_init);
 716 module_exit(fuse_exit);