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   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 #include <linux/sched.h>
  21
  22 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
  23 MODULE_DESCRIPTION("Filesystem in Userspace");
  24 MODULE_LICENSE("GPL");
  25
  26 static struct kmem_cache *fuse_inode_cachep;
  27 struct list_head fuse_conn_list;
  28 DEFINE_MUTEX(fuse_mutex);
  29
  30 #define FUSE_SUPER_MAGIC 0x65735546
  31
  32 struct fuse_mount_data {
  33         int fd;
  34         unsigned rootmode;
  35         unsigned user_id;
  36         unsigned group_id;
  37         unsigned fd_present : 1;
  38         unsigned rootmode_present : 1;
  39         unsigned user_id_present : 1;
  40         unsigned group_id_present : 1;
  41         unsigned flags;
  42         unsigned max_read;
  43         unsigned blksize;
  44 };
  45
  46 static struct inode *fuse_alloc_inode(struct super_block *sb)
  47 {
  48         struct inode *inode;
  49         struct fuse_inode *fi;
  50
  51         inode = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
  52         if (!inode)
  53                 return NULL;
  54
  55         fi = get_fuse_inode(inode);
  56         fi->i_time = 0;
  57         fi->nodeid = 0;
  58         fi->nlookup = 0;
  59         fi->forget_req = fuse_request_alloc();
  60         if (!fi->forget_req) {
  61                 kmem_cache_free(fuse_inode_cachep, inode);
  62                 return NULL;
  63         }
  64
  65         return inode;
  66 }
  67
  68 static void fuse_destroy_inode(struct inode *inode)
  69 {
  70         struct fuse_inode *fi = get_fuse_inode(inode);
  71         if (fi->forget_req)
  72                 fuse_request_free(fi->forget_req);
  73         kmem_cache_free(fuse_inode_cachep, inode);
  74 }
  75
  76 static void fuse_read_inode(struct inode *inode)
  77 {
  78         /* No op */
  79 }
  80
  81 void fuse_send_forget(struct fuse_conn *fc, struct fuse_req *req,
  82                       unsigned long nodeid, u64 nlookup)
  83 {
  84         struct fuse_forget_in *inarg = &req->misc.forget_in;
  85         inarg->nlookup = nlookup;
  86         req->in.h.opcode = FUSE_FORGET;
  87         req->in.h.nodeid = nodeid;
  88         req->in.numargs = 1;
  89         req->in.args[0].size = sizeof(struct fuse_forget_in);
  90         req->in.args[0].value = inarg;
  91         request_send_noreply(fc, req);
  92 }
  93
  94 static void fuse_clear_inode(struct inode *inode)
  95 {
  96         if (inode->i_sb->s_flags & MS_ACTIVE) {
  97                 struct fuse_conn *fc = get_fuse_conn(inode);
  98                 struct fuse_inode *fi = get_fuse_inode(inode);
  99                 fuse_send_forget(fc, fi->forget_req, fi->nodeid, fi->nlookup);
 100                 fi->forget_req = NULL;
 101         }
 102 }
 103
 104 static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
 105 {
 106         if (*flags & MS_MANDLOCK)
 107                 return -EINVAL;
 108
 109         return 0;
 110 }
 111
 112 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr)
 113 {
 114         struct fuse_conn *fc = get_fuse_conn(inode);
 115         if (S_ISREG(inode->i_mode) && i_size_read(inode) != attr->size)
 116                 invalidate_mapping_pages(inode->i_mapping, 0, -1);
 117
 118         inode->i_ino     = attr->ino;
 119         inode->i_mode    = (inode->i_mode & S_IFMT) + (attr->mode & 07777);
 120         inode->i_nlink   = attr->nlink;
 121         inode->i_uid     = attr->uid;
 122         inode->i_gid     = attr->gid;
 123         spin_lock(&fc->lock);
 124         i_size_write(inode, attr->size);
 125         spin_unlock(&fc->lock);
 126         inode->i_blocks  = attr->blocks;
 127         inode->i_atime.tv_sec   = attr->atime;
 128         inode->i_atime.tv_nsec  = attr->atimensec;
 129         inode->i_mtime.tv_sec   = attr->mtime;
 130         inode->i_mtime.tv_nsec  = attr->mtimensec;
 131         inode->i_ctime.tv_sec   = attr->ctime;
 132         inode->i_ctime.tv_nsec  = attr->ctimensec;
 133 }
 134
 135 static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
 136 {
 137         inode->i_mode = attr->mode & S_IFMT;
 138         inode->i_size = attr->size;
 139         if (S_ISREG(inode->i_mode)) {
 140                 fuse_init_common(inode);
 141                 fuse_init_file_inode(inode);
 142         } else if (S_ISDIR(inode->i_mode))
 143                 fuse_init_dir(inode);
 144         else if (S_ISLNK(inode->i_mode))
 145                 fuse_init_symlink(inode);
 146         else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
 147                  S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
 148                 fuse_init_common(inode);
 149                 init_special_inode(inode, inode->i_mode,
 150                                    new_decode_dev(attr->rdev));
 151         } else
 152                 BUG();
 153 }
 154
 155 static int fuse_inode_eq(struct inode *inode, void *_nodeidp)
 156 {
 157         unsigned long nodeid = *(unsigned long *) _nodeidp;
 158         if (get_node_id(inode) == nodeid)
 159                 return 1;
 160         else
 161                 return 0;
 162 }
 163
 164 static int fuse_inode_set(struct inode *inode, void *_nodeidp)
 165 {
 166         unsigned long nodeid = *(unsigned long *) _nodeidp;
 167         get_fuse_inode(inode)->nodeid = nodeid;
 168         return 0;
 169 }
 170
 171 struct inode *fuse_iget(struct super_block *sb, unsigned long nodeid,
 172                         int generation, struct fuse_attr *attr)
 173 {
 174         struct inode *inode;
 175         struct fuse_inode *fi;
 176         struct fuse_conn *fc = get_fuse_conn_super(sb);
 177
 178  retry:
 179         inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
 180         if (!inode)
 181                 return NULL;
 182
 183         if ((inode->i_state & I_NEW)) {
 184                 inode->i_flags |= S_NOATIME|S_NOCMTIME;
 185                 inode->i_generation = generation;
 186                 inode->i_data.backing_dev_info = &fc->bdi;
 187                 fuse_init_inode(inode, attr);
 188                 unlock_new_inode(inode);
 189         } else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
 190                 /* Inode has changed type, any I/O on the old should fail */
 191                 make_bad_inode(inode);
 192                 iput(inode);
 193                 goto retry;
 194         }
 195
 196         fi = get_fuse_inode(inode);
 197         spin_lock(&fc->lock);
 198         fi->nlookup ++;
 199         spin_unlock(&fc->lock);
 200         fuse_change_attributes(inode, attr);
 201         return inode;
 202 }
 203
 204 static void fuse_umount_begin(struct vfsmount *vfsmnt, int flags)
 205 {
 206         if (flags & MNT_FORCE)
 207                 fuse_abort_conn(get_fuse_conn_super(vfsmnt->mnt_sb));
 208 }
 209
 210 static void fuse_send_destroy(struct fuse_conn *fc)
 211 {
 212         struct fuse_req *req = fc->destroy_req;
 213         if (req && fc->conn_init) {
 214                 fc->destroy_req = NULL;
 215                 req->in.h.opcode = FUSE_DESTROY;
 216                 req->force = 1;
 217                 request_send(fc, req);
 218                 fuse_put_request(fc, req);
 219         }
 220 }
 221
 222 static void fuse_put_super(struct super_block *sb)
 223 {
 224         struct fuse_conn *fc = get_fuse_conn_super(sb);
 225
 226         fuse_send_destroy(fc);
 227         spin_lock(&fc->lock);
 228         fc->connected = 0;
 229         fc->blocked = 0;
 230         spin_unlock(&fc->lock);
 231         /* Flush all readers on this fs */
 232         kill_fasync(&fc->fasync, SIGIO, POLL_IN);
 233         wake_up_all(&fc->waitq);
 234         wake_up_all(&fc->blocked_waitq);
 235         wake_up_all(&fc->reserved_req_waitq);
 236         mutex_lock(&fuse_mutex);
 237         list_del(&fc->entry);
 238         fuse_ctl_remove_conn(fc);
 239         mutex_unlock(&fuse_mutex);
 240         fuse_conn_put(fc);
 241 }
 242
 243 static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
 244 {
 245         stbuf->f_type    = FUSE_SUPER_MAGIC;
 246         stbuf->f_bsize   = attr->bsize;
 247         stbuf->f_frsize  = attr->frsize;
 248         stbuf->f_blocks  = attr->blocks;
 249         stbuf->f_bfree   = attr->bfree;
 250         stbuf->f_bavail  = attr->bavail;
 251         stbuf->f_files   = attr->files;
 252         stbuf->f_ffree   = attr->ffree;
 253         stbuf->f_namelen = attr->namelen;
 254         /* fsid is left zero */
 255 }
 256
 257 static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
 258 {
 259         struct super_block *sb = dentry->d_sb;
 260         struct fuse_conn *fc = get_fuse_conn_super(sb);
 261         struct fuse_req *req;
 262         struct fuse_statfs_out outarg;
 263         int err;
 264
 265         req = fuse_get_req(fc);
 266         if (IS_ERR(req))
 267                 return PTR_ERR(req);
 268
 269         memset(&outarg, 0, sizeof(outarg));
 270         req->in.numargs = 0;
 271         req->in.h.opcode = FUSE_STATFS;
 272         req->in.h.nodeid = get_node_id(dentry->d_inode);
 273         req->out.numargs = 1;
 274         req->out.args[0].size =
 275                 fc->minor < 4 ? FUSE_COMPAT_STATFS_SIZE : sizeof(outarg);
 276         req->out.args[0].value = &outarg;
 277         request_send(fc, req);
 278         err = req->out.h.error;
 279         if (!err)
 280                 convert_fuse_statfs(buf, &outarg.st);
 281         fuse_put_request(fc, req);
 282         return err;
 283 }
 284
 285 enum {
 286         OPT_FD,
 287         OPT_ROOTMODE,
 288         OPT_USER_ID,
 289         OPT_GROUP_ID,
 290         OPT_DEFAULT_PERMISSIONS,
 291         OPT_ALLOW_OTHER,
 292         OPT_MAX_READ,
 293         OPT_BLKSIZE,
 294         OPT_ERR
 295 };
 296
 297 static match_table_t tokens = {
 298         {OPT_FD,                        "fd=%u"},
 299         {OPT_ROOTMODE,                  "rootmode=%o"},
 300         {OPT_USER_ID,                   "user_id=%u"},
 301         {OPT_GROUP_ID,                  "group_id=%u"},
 302         {OPT_DEFAULT_PERMISSIONS,       "default_permissions"},
 303         {OPT_ALLOW_OTHER,               "allow_other"},
 304         {OPT_MAX_READ,                  "max_read=%u"},
 305         {OPT_BLKSIZE,                   "blksize=%u"},
 306         {OPT_ERR,                       NULL}
 307 };
 308
 309 static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
 310 {
 311         char *p;
 312         memset(d, 0, sizeof(struct fuse_mount_data));
 313         d->max_read = ~0;
 314         d->blksize = 512;
 315
 316         while ((p = strsep(&opt, ",")) != NULL) {
 317                 int token;
 318                 int value;
 319                 substring_t args[MAX_OPT_ARGS];
 320                 if (!*p)
 321                         continue;
 322
 323                 token = match_token(p, tokens, args);
 324                 switch (token) {
 325                 case OPT_FD:
 326                         if (match_int(&args[0], &value))
 327                                 return 0;
 328                         d->fd = value;
 329                         d->fd_present = 1;
 330                         break;
 331
 332                 case OPT_ROOTMODE:
 333                         if (match_octal(&args[0], &value))
 334                                 return 0;
 335                         if (!fuse_valid_type(value))
 336                                 return 0;
 337                         d->rootmode = value;
 338                         d->rootmode_present = 1;
 339                         break;
 340
 341                 case OPT_USER_ID:
 342                         if (match_int(&args[0], &value))
 343                                 return 0;
 344                         d->user_id = value;
 345                         d->user_id_present = 1;
 346                         break;
 347
 348                 case OPT_GROUP_ID:
 349                         if (match_int(&args[0], &value))
 350                                 return 0;
 351                         d->group_id = value;
 352                         d->group_id_present = 1;
 353                         break;
 354
 355                 case OPT_DEFAULT_PERMISSIONS:
 356                         d->flags |= FUSE_DEFAULT_PERMISSIONS;
 357                         break;
 358
 359                 case OPT_ALLOW_OTHER:
 360                         d->flags |= FUSE_ALLOW_OTHER;
 361                         break;
 362
 363                 case OPT_MAX_READ:
 364                         if (match_int(&args[0], &value))
 365                                 return 0;
 366                         d->max_read = value;
 367                         break;
 368
 369                 case OPT_BLKSIZE:
 370                         if (!is_bdev || match_int(&args[0], &value))
 371                                 return 0;
 372                         d->blksize = value;
 373                         break;
 374
 375                 default:
 376                         return 0;
 377                 }
 378         }
 379
 380         if (!d->fd_present || !d->rootmode_present ||
 381             !d->user_id_present || !d->group_id_present)
 382                 return 0;
 383
 384         return 1;
 385 }
 386
 387 static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt)
 388 {
 389         struct fuse_conn *fc = get_fuse_conn_super(mnt->mnt_sb);
 390
 391         seq_printf(m, ",user_id=%u", fc->user_id);
 392         seq_printf(m, ",group_id=%u", fc->group_id);
 393         if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
 394                 seq_puts(m, ",default_permissions");
 395         if (fc->flags & FUSE_ALLOW_OTHER)
 396                 seq_puts(m, ",allow_other");
 397         if (fc->max_read != ~0)
 398                 seq_printf(m, ",max_read=%u", fc->max_read);
 399         return 0;
 400 }
 401
 402 static struct fuse_conn *new_conn(void)
 403 {
 404         struct fuse_conn *fc;
 405         int err;
 406
 407         fc = kzalloc(sizeof(*fc), GFP_KERNEL);
 408         if (fc) {
 409                 spin_lock_init(&fc->lock);
 410                 mutex_init(&fc->inst_mutex);
 411                 atomic_set(&fc->count, 1);
 412                 init_waitqueue_head(&fc->waitq);
 413                 init_waitqueue_head(&fc->blocked_waitq);
 414                 init_waitqueue_head(&fc->reserved_req_waitq);
 415                 INIT_LIST_HEAD(&fc->pending);
 416                 INIT_LIST_HEAD(&fc->processing);
 417                 INIT_LIST_HEAD(&fc->io);
 418                 INIT_LIST_HEAD(&fc->interrupts);
 419                 atomic_set(&fc->num_waiting, 0);
 420                 fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
 421                 fc->bdi.unplug_io_fn = default_unplug_io_fn;
 422                 err = bdi_init(&fc->bdi);
 423                 if (err) {
 424                         kfree(fc);
 425                         fc = NULL;
 426                         goto out;
 427                 }
 428                 fc->reqctr = 0;
 429                 fc->blocked = 1;
 430                 get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
 431         }
 432 out:
 433         return fc;
 434 }
 435
 436 void fuse_conn_put(struct fuse_conn *fc)
 437 {
 438         if (atomic_dec_and_test(&fc->count)) {
 439                 if (fc->destroy_req)
 440                         fuse_request_free(fc->destroy_req);
 441                 mutex_destroy(&fc->inst_mutex);
 442                 bdi_destroy(&fc->bdi);
 443                 kfree(fc);
 444         }
 445 }
 446
 447 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
 448 {
 449         atomic_inc(&fc->count);
 450         return fc;
 451 }
 452
 453 static struct inode *get_root_inode(struct super_block *sb, unsigned mode)
 454 {
 455         struct fuse_attr attr;
 456         memset(&attr, 0, sizeof(attr));
 457
 458         attr.mode = mode;
 459         attr.ino = FUSE_ROOT_ID;
 460         return fuse_iget(sb, 1, 0, &attr);
 461 }
 462
 463 static const struct super_operations fuse_super_operations = {
 464         .alloc_inode    = fuse_alloc_inode,
 465         .destroy_inode  = fuse_destroy_inode,
 466         .read_inode     = fuse_read_inode,
 467         .clear_inode    = fuse_clear_inode,
 468         .drop_inode     = generic_delete_inode,
 469         .remount_fs     = fuse_remount_fs,
 470         .put_super      = fuse_put_super,
 471         .umount_begin   = fuse_umount_begin,
 472         .statfs         = fuse_statfs,
 473         .show_options   = fuse_show_options,
 474 };
 475
 476 static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
 477 {
 478         struct fuse_init_out *arg = &req->misc.init_out;
 479
 480         if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION)
 481                 fc->conn_error = 1;
 482         else {
 483                 unsigned long ra_pages;
 484
 485                 if (arg->minor >= 6) {
 486                         ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
 487                         if (arg->flags & FUSE_ASYNC_READ)
 488                                 fc->async_read = 1;
 489                         if (!(arg->flags & FUSE_POSIX_LOCKS))
 490                                 fc->no_lock = 1;
 491                 } else {
 492                         ra_pages = fc->max_read / PAGE_CACHE_SIZE;
 493                         fc->no_lock = 1;
 494                 }
 495
 496                 fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
 497                 fc->minor = arg->minor;
 498                 fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
 499                 fc->conn_init = 1;
 500         }
 501         fuse_put_request(fc, req);
 502         fc->blocked = 0;
 503         wake_up_all(&fc->blocked_waitq);
 504 }
 505
 506 static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
 507 {
 508         struct fuse_init_in *arg = &req->misc.init_in;
 509
 510         arg->major = FUSE_KERNEL_VERSION;
 511         arg->minor = FUSE_KERNEL_MINOR_VERSION;
 512         arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
 513         arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS;
 514         req->in.h.opcode = FUSE_INIT;
 515         req->in.numargs = 1;
 516         req->in.args[0].size = sizeof(*arg);
 517         req->in.args[0].value = arg;
 518         req->out.numargs = 1;
 519         /* Variable length arguement used for backward compatibility
 520            with interface version < 7.5.  Rest of init_out is zeroed
 521            by do_get_request(), so a short reply is not a problem */
 522         req->out.argvar = 1;
 523         req->out.args[0].size = sizeof(struct fuse_init_out);
 524         req->out.args[0].value = &req->misc.init_out;
 525         req->end = process_init_reply;
 526         request_send_background(fc, req);
 527 }
 528
 529 static u64 conn_id(void)
 530 {
 531         static u64 ctr = 1;
 532         return ctr++;
 533 }
 534
 535 static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 536 {
 537         struct fuse_conn *fc;
 538         struct inode *root;
 539         struct fuse_mount_data d;
 540         struct file *file;
 541         struct dentry *root_dentry;
 542         struct fuse_req *init_req;
 543         int err;
 544         int is_bdev = sb->s_bdev != NULL;
 545
 546         if (sb->s_flags & MS_MANDLOCK)
 547                 return -EINVAL;
 548
 549         if (!parse_fuse_opt((char *) data, &d, is_bdev))
 550                 return -EINVAL;
 551
 552         if (is_bdev) {
 553 #ifdef CONFIG_BLOCK
 554                 if (!sb_set_blocksize(sb, d.blksize))
 555                         return -EINVAL;
 556 #endif
 557         } else {
 558                 sb->s_blocksize = PAGE_CACHE_SIZE;
 559                 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
 560         }
 561         sb->s_magic = FUSE_SUPER_MAGIC;
 562         sb->s_op = &fuse_super_operations;
 563         sb->s_maxbytes = MAX_LFS_FILESIZE;
 564
 565         file = fget(d.fd);
 566         if (!file)
 567                 return -EINVAL;
 568
 569         if (file->f_op != &fuse_dev_operations)
 570                 return -EINVAL;
 571
 572         fc = new_conn();
 573         if (!fc)
 574                 return -ENOMEM;
 575
 576         fc->flags = d.flags;
 577         fc->user_id = d.user_id;
 578         fc->group_id = d.group_id;
 579         fc->max_read = d.max_read;
 580
 581         /* Used by get_root_inode() */
 582         sb->s_fs_info = fc;
 583
 584         err = -ENOMEM;
 585         root = get_root_inode(sb, d.rootmode);
 586         if (!root)
 587                 goto err;
 588
 589         root_dentry = d_alloc_root(root);
 590         if (!root_dentry) {
 591                 iput(root);
 592                 goto err;
 593         }
 594
 595         init_req = fuse_request_alloc();
 596         if (!init_req)
 597                 goto err_put_root;
 598
 599         if (is_bdev) {
 600                 fc->destroy_req = fuse_request_alloc();
 601                 if (!fc->destroy_req)
 602                         goto err_put_root;
 603         }
 604
 605         mutex_lock(&fuse_mutex);
 606         err = -EINVAL;
 607         if (file->private_data)
 608                 goto err_unlock;
 609
 610         fc->id = conn_id();
 611         err = fuse_ctl_add_conn(fc);
 612         if (err)
 613                 goto err_unlock;
 614
 615         list_add_tail(&fc->entry, &fuse_conn_list);
 616         sb->s_root = root_dentry;
 617         fc->connected = 1;
 618         file->private_data = fuse_conn_get(fc);
 619         mutex_unlock(&fuse_mutex);
 620         /*
 621          * atomic_dec_and_test() in fput() provides the necessary
 622          * memory barrier for file->private_data to be visible on all
 623          * CPUs after this
 624          */
 625         fput(file);
 626
 627         fuse_send_init(fc, init_req);
 628
 629         return 0;
 630
 631  err_unlock:
 632         mutex_unlock(&fuse_mutex);
 633         fuse_request_free(init_req);
 634  err_put_root:
 635         dput(root_dentry);
 636  err:
 637         fput(file);
 638         fuse_conn_put(fc);
 639         return err;
 640 }
 641
 642 static int fuse_get_sb(struct file_system_type *fs_type,
 643                        int flags, const char *dev_name,
 644                        void *raw_data, struct vfsmount *mnt)
 645 {
 646         return get_sb_nodev(fs_type, flags, raw_data, fuse_fill_super, mnt);
 647 }
 648
 649 static struct file_system_type fuse_fs_type = {
 650         .owner          = THIS_MODULE,
 651         .name           = "fuse",
 652         .fs_flags       = FS_HAS_SUBTYPE,
 653         .get_sb         = fuse_get_sb,
 654         .kill_sb        = kill_anon_super,
 655 };
 656
 657 #ifdef CONFIG_BLOCK
 658 static int fuse_get_sb_blk(struct file_system_type *fs_type,
 659                            int flags, const char *dev_name,
 660                            void *raw_data, struct vfsmount *mnt)
 661 {
 662         return get_sb_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super,
 663                            mnt);
 664 }
 665
 666 static struct file_system_type fuseblk_fs_type = {
 667         .owner          = THIS_MODULE,
 668         .name           = "fuseblk",
 669         .get_sb         = fuse_get_sb_blk,
 670         .kill_sb        = kill_block_super,
 671         .fs_flags       = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
 672 };
 673
 674 static inline int register_fuseblk(void)
 675 {
 676         return register_filesystem(&fuseblk_fs_type);
 677 }
 678
 679 static inline void unregister_fuseblk(void)
 680 {
 681         unregister_filesystem(&fuseblk_fs_type);
 682 }
 683 #else
 684 static inline int register_fuseblk(void)
 685 {
 686         return 0;
 687 }
 688
 689 static inline void unregister_fuseblk(void)
 690 {
 691 }
 692 #endif
 693
 694 static decl_subsys(fuse, NULL, NULL);
 695 static decl_subsys(connections, NULL, NULL);
 696
 697 static void fuse_inode_init_once(struct kmem_cache *cachep, void *foo)
 698 {
 699         struct inode * inode = foo;
 700
 701         inode_init_once(inode);
 702 }
 703
 704 static int __init fuse_fs_init(void)
 705 {
 706         int err;
 707
 708         err = register_filesystem(&fuse_fs_type);
 709         if (err)
 710                 goto out;
 711
 712         err = register_fuseblk();
 713         if (err)
 714                 goto out_unreg;
 715
 716         fuse_inode_cachep = kmem_cache_create("fuse_inode",
 717                                               sizeof(struct fuse_inode),
 718                                               0, SLAB_HWCACHE_ALIGN,
 719                                               fuse_inode_init_once);
 720         err = -ENOMEM;
 721         if (!fuse_inode_cachep)
 722                 goto out_unreg2;
 723
 724         return 0;
 725
 726  out_unreg2:
 727         unregister_fuseblk();
 728  out_unreg:
 729         unregister_filesystem(&fuse_fs_type);
 730  out:
 731         return err;
 732 }
 733
 734 static void fuse_fs_cleanup(void)
 735 {
 736         unregister_filesystem(&fuse_fs_type);
 737         unregister_fuseblk();
 738         kmem_cache_destroy(fuse_inode_cachep);
 739 }
 740
 741 static int fuse_sysfs_init(void)
 742 {
 743         int err;
 744
 745         kobj_set_kset_s(&fuse_subsys, fs_subsys);
 746         err = subsystem_register(&fuse_subsys);
 747         if (err)
 748                 goto out_err;
 749
 750         kobj_set_kset_s(&connections_subsys, fuse_subsys);
 751         err = subsystem_register(&connections_subsys);
 752         if (err)
 753                 goto out_fuse_unregister;
 754
 755         return 0;
 756
 757  out_fuse_unregister:
 758         subsystem_unregister(&fuse_subsys);
 759  out_err:
 760         return err;
 761 }
 762
 763 static void fuse_sysfs_cleanup(void)
 764 {
 765         subsystem_unregister(&connections_subsys);
 766         subsystem_unregister(&fuse_subsys);
 767 }
 768
 769 static int __init fuse_init(void)
 770 {
 771         int res;
 772
 773         printk("fuse init (API version %i.%i)\n",
 774                FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
 775
 776         INIT_LIST_HEAD(&fuse_conn_list);
 777         res = fuse_fs_init();
 778         if (res)
 779                 goto err;
 780
 781         res = fuse_dev_init();
 782         if (res)
 783                 goto err_fs_cleanup;
 784
 785         res = fuse_sysfs_init();
 786         if (res)
 787                 goto err_dev_cleanup;
 788
 789         res = fuse_ctl_init();
 790         if (res)
 791                 goto err_sysfs_cleanup;
 792
 793         return 0;
 794
 795  err_sysfs_cleanup:
 796         fuse_sysfs_cleanup();
 797  err_dev_cleanup:
 798         fuse_dev_cleanup();
 799  err_fs_cleanup:
 800         fuse_fs_cleanup();
 801  err:
 802         return res;
 803 }
 804
 805 static void __exit fuse_exit(void)
 806 {
 807         printk(KERN_DEBUG "fuse exit\n");
 808
 809         fuse_ctl_cleanup();
 810         fuse_sysfs_cleanup();
 811         fuse_fs_cleanup();
 812         fuse_dev_cleanup();
 813 }
 814
 815 module_init(fuse_init);
 816 module_exit(fuse_exit);