fs/fuse/inode.c

   1 /*
   2   FUSE: Filesystem in Userspace
   3   Copyright (C) 2001-2006  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/seq_file.h>
  15 #include <linux/init.h>
  16 #include <linux/module.h>
  17 #include <linux/parser.h>
  18 #include <linux/statfs.h>
  19 #include <linux/random.h>
  20
  21 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
  22 MODULE_DESCRIPTION("Filesystem in Userspace");
  23 MODULE_LICENSE("GPL");
  24
  25 static kmem_cache_t *fuse_inode_cachep;
  26 struct list_head fuse_conn_list;
  27 DEFINE_MUTEX(fuse_mutex);
  28
  29 #define FUSE_SUPER_MAGIC 0x65735546
  30
  31 struct fuse_mount_data {
  32         int fd;
  33         unsigned rootmode;
  34         unsigned user_id;
  35         unsigned group_id;
  36         unsigned fd_present : 1;
  37         unsigned rootmode_present : 1;
  38         unsigned user_id_present : 1;
  39         unsigned group_id_present : 1;
  40         unsigned flags;
  41         unsigned max_read;
  42 };
  43
  44 static struct inode *fuse_alloc_inode(struct super_block *sb)
  45 {
  46         struct inode *inode;
  47         struct fuse_inode *fi;
  48
  49         inode = kmem_cache_alloc(fuse_inode_cachep, SLAB_KERNEL);
  50         if (!inode)
  51                 return NULL;
  52
  53         fi = get_fuse_inode(inode);
  54         fi->i_time = jiffies - 1;
  55         fi->nodeid = 0;
  56         fi->nlookup = 0;
  57         fi->forget_req = fuse_request_alloc();
  58         if (!fi->forget_req) {
  59                 kmem_cache_free(fuse_inode_cachep, inode);
  60                 return NULL;
  61         }
  62
  63         return inode;
  64 }
  65
  66 static void fuse_destroy_inode(struct inode *inode)
  67 {
  68         struct fuse_inode *fi = get_fuse_inode(inode);
  69         if (fi->forget_req)
  70                 fuse_request_free(fi->forget_req);
  71         kmem_cache_free(fuse_inode_cachep, inode);
  72 }
  73
  74 static void fuse_read_inode(struct inode *inode)
  75 {
  76         /* No op */
  77 }
  78
  79 void fuse_send_forget(struct fuse_conn *fc, struct fuse_req *req,
  80                       unsigned long nodeid, u64 nlookup)
  81 {
  82         struct fuse_forget_in *inarg = &req->misc.forget_in;
  83         inarg->nlookup = nlookup;
  84         req->in.h.opcode = FUSE_FORGET;
  85         req->in.h.nodeid = nodeid;
  86         req->in.numargs = 1;
  87         req->in.args[0].size = sizeof(struct fuse_forget_in);
  88         req->in.args[0].value = inarg;
  89         request_send_noreply(fc, req);
  90 }
  91
  92 static void fuse_clear_inode(struct inode *inode)
  93 {
  94         if (inode->i_sb->s_flags & MS_ACTIVE) {
  95                 struct fuse_conn *fc = get_fuse_conn(inode);
  96                 struct fuse_inode *fi = get_fuse_inode(inode);
  97                 fuse_send_forget(fc, fi->forget_req, fi->nodeid, fi->nlookup);
  98                 fi->forget_req = NULL;
  99         }
 100 }
 101
 102 static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
 103 {
 104         if (*flags & MS_MANDLOCK)
 105                 return -EINVAL;
 106
 107         return 0;
 108 }
 109
 110 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr)
 111 {
 112         if (S_ISREG(inode->i_mode) && i_size_read(inode) != attr->size)
 113                 invalidate_inode_pages(inode->i_mapping);
 114
 115         inode->i_ino     = attr->ino;
 116         inode->i_mode    = (inode->i_mode & S_IFMT) + (attr->mode & 07777);
 117         inode->i_nlink   = attr->nlink;
 118         inode->i_uid     = attr->uid;
 119         inode->i_gid     = attr->gid;
 120         i_size_write(inode, attr->size);
 121         inode->i_blksize = PAGE_CACHE_SIZE;
 122         inode->i_blocks  = attr->blocks;
 123         inode->i_atime.tv_sec   = attr->atime;
 124         inode->i_atime.tv_nsec  = attr->atimensec;
 125         inode->i_mtime.tv_sec   = attr->mtime;
 126         inode->i_mtime.tv_nsec  = attr->mtimensec;
 127         inode->i_ctime.tv_sec   = attr->ctime;
 128         inode->i_ctime.tv_nsec  = attr->ctimensec;
 129 }
 130
 131 static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
 132 {
 133         inode->i_mode = attr->mode & S_IFMT;
 134         i_size_write(inode, attr->size);
 135         if (S_ISREG(inode->i_mode)) {
 136                 fuse_init_common(inode);
 137                 fuse_init_file_inode(inode);
 138         } else if (S_ISDIR(inode->i_mode))
 139                 fuse_init_dir(inode);
 140         else if (S_ISLNK(inode->i_mode))
 141                 fuse_init_symlink(inode);
 142         else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
 143                  S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
 144                 fuse_init_common(inode);
 145                 init_special_inode(inode, inode->i_mode,
 146                                    new_decode_dev(attr->rdev));
 147         } else
 148                 BUG();
 149 }
 150
 151 static int fuse_inode_eq(struct inode *inode, void *_nodeidp)
 152 {
 153         unsigned long nodeid = *(unsigned long *) _nodeidp;
 154         if (get_node_id(inode) == nodeid)
 155                 return 1;
 156         else
 157                 return 0;
 158 }
 159
 160 static int fuse_inode_set(struct inode *inode, void *_nodeidp)
 161 {
 162         unsigned long nodeid = *(unsigned long *) _nodeidp;
 163         get_fuse_inode(inode)->nodeid = nodeid;
 164         return 0;
 165 }
 166
 167 struct inode *fuse_iget(struct super_block *sb, unsigned long nodeid,
 168                         int generation, struct fuse_attr *attr)
 169 {
 170         struct inode *inode;
 171         struct fuse_inode *fi;
 172         struct fuse_conn *fc = get_fuse_conn_super(sb);
 173         int retried = 0;
 174
 175  retry:
 176         inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
 177         if (!inode)
 178                 return NULL;
 179
 180         if ((inode->i_state & I_NEW)) {
 181                 inode->i_flags |= S_NOATIME|S_NOCMTIME;
 182                 inode->i_generation = generation;
 183                 inode->i_data.backing_dev_info = &fc->bdi;
 184                 fuse_init_inode(inode, attr);
 185                 unlock_new_inode(inode);
 186         } else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
 187                 BUG_ON(retried);
 188                 /* Inode has changed type, any I/O on the old should fail */
 189                 make_bad_inode(inode);
 190                 iput(inode);
 191                 retried = 1;
 192                 goto retry;
 193         }
 194
 195         fi = get_fuse_inode(inode);
 196         fi->nlookup ++;
 197         fuse_change_attributes(inode, attr);
 198         return inode;
 199 }
 200
 201 static void fuse_umount_begin(struct super_block *sb)
 202 {
 203         fuse_abort_conn(get_fuse_conn_super(sb));
 204 }
 205
 206 static void fuse_put_super(struct super_block *sb)
 207 {
 208         struct fuse_conn *fc = get_fuse_conn_super(sb);
 209
 210         spin_lock(&fc->lock);
 211         fc->connected = 0;
 212         fc->blocked = 0;
 213         spin_unlock(&fc->lock);
 214         /* Flush all readers on this fs */
 215         kill_fasync(&fc->fasync, SIGIO, POLL_IN);
 216         wake_up_all(&fc->waitq);
 217         wake_up_all(&fc->blocked_waitq);
 218         mutex_lock(&fuse_mutex);
 219         list_del(&fc->entry);
 220         fuse_ctl_remove_conn(fc);
 221         mutex_unlock(&fuse_mutex);
 222         fuse_conn_put(fc);
 223 }
 224
 225 static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
 226 {
 227         stbuf->f_type    = FUSE_SUPER_MAGIC;
 228         stbuf->f_bsize   = attr->bsize;
 229         stbuf->f_frsize  = attr->frsize;
 230         stbuf->f_blocks  = attr->blocks;
 231         stbuf->f_bfree   = attr->bfree;
 232         stbuf->f_bavail  = attr->bavail;
 233         stbuf->f_files   = attr->files;
 234         stbuf->f_ffree   = attr->ffree;
 235         stbuf->f_namelen = attr->namelen;
 236         /* fsid is left zero */
 237 }
 238
 239 static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
 240 {
 241         struct super_block *sb = dentry->d_sb;
 242         struct fuse_conn *fc = get_fuse_conn_super(sb);
 243         struct fuse_req *req;
 244         struct fuse_statfs_out outarg;
 245         int err;
 246
 247         req = fuse_get_req(fc);
 248         if (IS_ERR(req))
 249                 return PTR_ERR(req);
 250
 251         memset(&outarg, 0, sizeof(outarg));
 252         req->in.numargs = 0;
 253         req->in.h.opcode = FUSE_STATFS;
 254         req->out.numargs = 1;
 255         req->out.args[0].size =
 256                 fc->minor < 4 ? FUSE_COMPAT_STATFS_SIZE : sizeof(outarg);
 257         req->out.args[0].value = &outarg;
 258         request_send(fc, req);
 259         err = req->out.h.error;
 260         if (!err)
 261                 convert_fuse_statfs(buf, &outarg.st);
 262         fuse_put_request(fc, req);
 263         return err;
 264 }
 265
 266 enum {
 267         OPT_FD,
 268         OPT_ROOTMODE,
 269         OPT_USER_ID,
 270         OPT_GROUP_ID,
 271         OPT_DEFAULT_PERMISSIONS,
 272         OPT_ALLOW_OTHER,
 273         OPT_MAX_READ,
 274         OPT_ERR
 275 };
 276
 277 static match_table_t tokens = {
 278         {OPT_FD,                        "fd=%u"},
 279         {OPT_ROOTMODE,                  "rootmode=%o"},
 280         {OPT_USER_ID,                   "user_id=%u"},
 281         {OPT_GROUP_ID,                  "group_id=%u"},
 282         {OPT_DEFAULT_PERMISSIONS,       "default_permissions"},
 283         {OPT_ALLOW_OTHER,               "allow_other"},
 284         {OPT_MAX_READ,                  "max_read=%u"},
 285         {OPT_ERR,                       NULL}
 286 };
 287
 288 static int parse_fuse_opt(char *opt, struct fuse_mount_data *d)
 289 {
 290         char *p;
 291         memset(d, 0, sizeof(struct fuse_mount_data));
 292         d->max_read = ~0;
 293
 294         while ((p = strsep(&opt, ",")) != NULL) {
 295                 int token;
 296                 int value;
 297                 substring_t args[MAX_OPT_ARGS];
 298                 if (!*p)
 299                         continue;
 300
 301                 token = match_token(p, tokens, args);
 302                 switch (token) {
 303                 case OPT_FD:
 304                         if (match_int(&args[0], &value))
 305                                 return 0;
 306                         d->fd = value;
 307                         d->fd_present = 1;
 308                         break;
 309
 310                 case OPT_ROOTMODE:
 311                         if (match_octal(&args[0], &value))
 312                                 return 0;
 313                         d->rootmode = value;
 314                         d->rootmode_present = 1;
 315                         break;
 316
 317                 case OPT_USER_ID:
 318                         if (match_int(&args[0], &value))
 319                                 return 0;
 320                         d->user_id = value;
 321                         d->user_id_present = 1;
 322                         break;
 323
 324                 case OPT_GROUP_ID:
 325                         if (match_int(&args[0], &value))
 326                                 return 0;
 327                         d->group_id = value;
 328                         d->group_id_present = 1;
 329                         break;
 330
 331                 case OPT_DEFAULT_PERMISSIONS:
 332                         d->flags |= FUSE_DEFAULT_PERMISSIONS;
 333                         break;
 334
 335                 case OPT_ALLOW_OTHER:
 336                         d->flags |= FUSE_ALLOW_OTHER;
 337                         break;
 338
 339                 case OPT_MAX_READ:
 340                         if (match_int(&args[0], &value))
 341                                 return 0;
 342                         d->max_read = value;
 343                         break;
 344
 345                 default:
 346                         return 0;
 347                 }
 348         }
 349
 350         if (!d->fd_present || !d->rootmode_present ||
 351             !d->user_id_present || !d->group_id_present)
 352                 return 0;
 353
 354         return 1;
 355 }
 356
 357 static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt)
 358 {
 359         struct fuse_conn *fc = get_fuse_conn_super(mnt->mnt_sb);
 360
 361         seq_printf(m, ",user_id=%u", fc->user_id);
 362         seq_printf(m, ",group_id=%u", fc->group_id);
 363         if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
 364                 seq_puts(m, ",default_permissions");
 365         if (fc->flags & FUSE_ALLOW_OTHER)
 366                 seq_puts(m, ",allow_other");
 367         if (fc->max_read != ~0)
 368                 seq_printf(m, ",max_read=%u", fc->max_read);
 369         return 0;
 370 }
 371
 372 static struct fuse_conn *new_conn(void)
 373 {
 374         struct fuse_conn *fc;
 375
 376         fc = kzalloc(sizeof(*fc), GFP_KERNEL);
 377         if (fc) {
 378                 spin_lock_init(&fc->lock);
 379                 atomic_set(&fc->count, 1);
 380                 init_waitqueue_head(&fc->waitq);
 381                 init_waitqueue_head(&fc->blocked_waitq);
 382                 INIT_LIST_HEAD(&fc->pending);
 383                 INIT_LIST_HEAD(&fc->processing);
 384                 INIT_LIST_HEAD(&fc->io);
 385                 INIT_LIST_HEAD(&fc->interrupts);
 386                 atomic_set(&fc->num_waiting, 0);
 387                 fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
 388                 fc->bdi.unplug_io_fn = default_unplug_io_fn;
 389                 fc->reqctr = 0;
 390                 fc->blocked = 1;
 391                 get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
 392         }
 393         return fc;
 394 }
 395
 396 void fuse_conn_put(struct fuse_conn *fc)
 397 {
 398         if (atomic_dec_and_test(&fc->count))
 399                 kfree(fc);
 400 }
 401
 402 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
 403 {
 404         atomic_inc(&fc->count);
 405         return fc;
 406 }
 407
 408 static struct inode *get_root_inode(struct super_block *sb, unsigned mode)
 409 {
 410         struct fuse_attr attr;
 411         memset(&attr, 0, sizeof(attr));
 412
 413         attr.mode = mode;
 414         attr.ino = FUSE_ROOT_ID;
 415         return fuse_iget(sb, 1, 0, &attr);
 416 }
 417
 418 static struct super_operations fuse_super_operations = {
 419         .alloc_inode    = fuse_alloc_inode,
 420         .destroy_inode  = fuse_destroy_inode,
 421         .read_inode     = fuse_read_inode,
 422         .clear_inode    = fuse_clear_inode,
 423         .remount_fs     = fuse_remount_fs,
 424         .put_super      = fuse_put_super,
 425         .umount_begin   = fuse_umount_begin,
 426         .statfs         = fuse_statfs,
 427         .show_options   = fuse_show_options,
 428 };
 429
 430 static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
 431 {
 432         struct fuse_init_out *arg = &req->misc.init_out;
 433
 434         if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION)
 435                 fc->conn_error = 1;
 436         else {
 437                 unsigned long ra_pages;
 438
 439                 if (arg->minor >= 6) {
 440                         ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
 441                         if (arg->flags & FUSE_ASYNC_READ)
 442                                 fc->async_read = 1;
 443                         if (!(arg->flags & FUSE_POSIX_LOCKS))
 444                                 fc->no_lock = 1;
 445                 } else {
 446                         ra_pages = fc->max_read / PAGE_CACHE_SIZE;
 447                         fc->no_lock = 1;
 448                 }
 449
 450                 fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
 451                 fc->minor = arg->minor;
 452                 fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
 453         }
 454         fuse_put_request(fc, req);
 455         fc->blocked = 0;
 456         wake_up_all(&fc->blocked_waitq);
 457 }
 458
 459 static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
 460 {
 461         struct fuse_init_in *arg = &req->misc.init_in;
 462
 463         arg->major = FUSE_KERNEL_VERSION;
 464         arg->minor = FUSE_KERNEL_MINOR_VERSION;
 465         arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
 466         arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS;
 467         req->in.h.opcode = FUSE_INIT;
 468         req->in.numargs = 1;
 469         req->in.args[0].size = sizeof(*arg);
 470         req->in.args[0].value = arg;
 471         req->out.numargs = 1;
 472         /* Variable length arguement used for backward compatibility
 473            with interface version < 7.5.  Rest of init_out is zeroed
 474            by do_get_request(), so a short reply is not a problem */
 475         req->out.argvar = 1;
 476         req->out.args[0].size = sizeof(struct fuse_init_out);
 477         req->out.args[0].value = &req->misc.init_out;
 478         req->end = process_init_reply;
 479         request_send_background(fc, req);
 480 }
 481
 482 static u64 conn_id(void)
 483 {
 484         static u64 ctr = 1;
 485         return ctr++;
 486 }
 487
 488 static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 489 {
 490         struct fuse_conn *fc;
 491         struct inode *root;
 492         struct fuse_mount_data d;
 493         struct file *file;
 494         struct dentry *root_dentry;
 495         struct fuse_req *init_req;
 496         int err;
 497
 498         if (sb->s_flags & MS_MANDLOCK)
 499                 return -EINVAL;
 500
 501         if (!parse_fuse_opt((char *) data, &d))
 502                 return -EINVAL;
 503
 504         sb->s_blocksize = PAGE_CACHE_SIZE;
 505         sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
 506         sb->s_magic = FUSE_SUPER_MAGIC;
 507         sb->s_op = &fuse_super_operations;
 508         sb->s_maxbytes = MAX_LFS_FILESIZE;
 509
 510         file = fget(d.fd);
 511         if (!file)
 512                 return -EINVAL;
 513
 514         if (file->f_op != &fuse_dev_operations)
 515                 return -EINVAL;
 516
 517         fc = new_conn();
 518         if (!fc)
 519                 return -ENOMEM;
 520
 521         fc->flags = d.flags;
 522         fc->user_id = d.user_id;
 523         fc->group_id = d.group_id;
 524         fc->max_read = d.max_read;
 525
 526         /* Used by get_root_inode() */
 527         sb->s_fs_info = fc;
 528
 529         err = -ENOMEM;
 530         root = get_root_inode(sb, d.rootmode);
 531         if (!root)
 532                 goto err;
 533
 534         root_dentry = d_alloc_root(root);
 535         if (!root_dentry) {
 536                 iput(root);
 537                 goto err;
 538         }
 539
 540         init_req = fuse_request_alloc();
 541         if (!init_req)
 542                 goto err_put_root;
 543
 544         mutex_lock(&fuse_mutex);
 545         err = -EINVAL;
 546         if (file->private_data)
 547                 goto err_unlock;
 548
 549         fc->id = conn_id();
 550         err = fuse_ctl_add_conn(fc);
 551         if (err)
 552                 goto err_unlock;
 553
 554         list_add_tail(&fc->entry, &fuse_conn_list);
 555         sb->s_root = root_dentry;
 556         fc->connected = 1;
 557         file->private_data = fuse_conn_get(fc);
 558         mutex_unlock(&fuse_mutex);
 559         /*
 560          * atomic_dec_and_test() in fput() provides the necessary
 561          * memory barrier for file->private_data to be visible on all
 562          * CPUs after this
 563          */
 564         fput(file);
 565
 566         fuse_send_init(fc, init_req);
 567
 568         return 0;
 569
 570  err_unlock:
 571         mutex_unlock(&fuse_mutex);
 572         fuse_request_free(init_req);
 573  err_put_root:
 574         dput(root_dentry);
 575  err:
 576         fput(file);
 577         fuse_conn_put(fc);
 578         return err;
 579 }
 580
 581 static int fuse_get_sb(struct file_system_type *fs_type,
 582                        int flags, const char *dev_name,
 583                        void *raw_data, struct vfsmount *mnt)
 584 {
 585         return get_sb_nodev(fs_type, flags, raw_data, fuse_fill_super, mnt);
 586 }
 587
 588 static struct file_system_type fuse_fs_type = {
 589         .owner          = THIS_MODULE,
 590         .name           = "fuse",
 591         .get_sb         = fuse_get_sb,
 592         .kill_sb        = kill_anon_super,
 593 };
 594
 595 static decl_subsys(fuse, NULL, NULL);
 596 static decl_subsys(connections, NULL, NULL);
 597
 598 static void fuse_inode_init_once(void *foo, kmem_cache_t *cachep,
 599                                  unsigned long flags)
 600 {
 601         struct inode * inode = foo;
 602
 603         if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
 604             SLAB_CTOR_CONSTRUCTOR)
 605                 inode_init_once(inode);
 606 }
 607
 608 static int __init fuse_fs_init(void)
 609 {
 610         int err;
 611
 612         err = register_filesystem(&fuse_fs_type);
 613         if (err)
 614                 printk("fuse: failed to register filesystem\n");
 615         else {
 616                 fuse_inode_cachep = kmem_cache_create("fuse_inode",
 617                                                       sizeof(struct fuse_inode),
 618                                                       0, SLAB_HWCACHE_ALIGN,
 619                                                       fuse_inode_init_once, NULL);
 620                 if (!fuse_inode_cachep) {
 621                         unregister_filesystem(&fuse_fs_type);
 622                         err = -ENOMEM;
 623                 }
 624         }
 625
 626         return err;
 627 }
 628
 629 static void fuse_fs_cleanup(void)
 630 {
 631         unregister_filesystem(&fuse_fs_type);
 632         kmem_cache_destroy(fuse_inode_cachep);
 633 }
 634
 635 static int fuse_sysfs_init(void)
 636 {
 637         int err;
 638
 639         kset_set_kset_s(&fuse_subsys, fs_subsys);
 640         err = subsystem_register(&fuse_subsys);
 641         if (err)
 642                 goto out_err;
 643
 644         kset_set_kset_s(&connections_subsys, fuse_subsys);
 645         err = subsystem_register(&connections_subsys);
 646         if (err)
 647                 goto out_fuse_unregister;
 648
 649         return 0;
 650
 651  out_fuse_unregister:
 652         subsystem_unregister(&fuse_subsys);
 653  out_err:
 654         return err;
 655 }
 656
 657 static void fuse_sysfs_cleanup(void)
 658 {
 659         subsystem_unregister(&connections_subsys);
 660         subsystem_unregister(&fuse_subsys);
 661 }
 662
 663 static int __init fuse_init(void)
 664 {
 665         int res;
 666
 667         printk("fuse init (API version %i.%i)\n",
 668                FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
 669
 670         INIT_LIST_HEAD(&fuse_conn_list);
 671         res = fuse_fs_init();
 672         if (res)
 673                 goto err;
 674
 675         res = fuse_dev_init();
 676         if (res)
 677                 goto err_fs_cleanup;
 678
 679         res = fuse_sysfs_init();
 680         if (res)
 681                 goto err_dev_cleanup;
 682
 683         res = fuse_ctl_init();
 684         if (res)
 685                 goto err_sysfs_cleanup;
 686
 687         return 0;
 688
 689  err_sysfs_cleanup:
 690         fuse_sysfs_cleanup();
 691  err_dev_cleanup:
 692         fuse_dev_cleanup();
 693  err_fs_cleanup:
 694         fuse_fs_cleanup();
 695  err:
 696         return res;
 697 }
 698
 699 static void __exit fuse_exit(void)
 700 {
 701         printk(KERN_DEBUG "fuse exit\n");
 702
 703         fuse_ctl_cleanup();
 704         fuse_sysfs_cleanup();
 705         fuse_fs_cleanup();
 706         fuse_dev_cleanup();
 707 }
 708
 709 module_init(fuse_init);
 710 module_exit(fuse_exit);