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 #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 static void fuse_truncate(struct address_space *mapping, loff_t offset)
 113 {
 114         /* See vmtruncate() */
 115         unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
 116         truncate_inode_pages(mapping, offset);
 117         unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
 118 }
 119
 120 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr)
 121 {
 122         struct fuse_conn *fc = get_fuse_conn(inode);
 123         loff_t oldsize;
 124
 125         inode->i_ino     = attr->ino;
 126         inode->i_mode    = (inode->i_mode & S_IFMT) + (attr->mode & 07777);
 127         inode->i_nlink   = attr->nlink;
 128         inode->i_uid     = attr->uid;
 129         inode->i_gid     = attr->gid;
 130         inode->i_blocks  = attr->blocks;
 131         inode->i_atime.tv_sec   = attr->atime;
 132         inode->i_atime.tv_nsec  = attr->atimensec;
 133         inode->i_mtime.tv_sec   = attr->mtime;
 134         inode->i_mtime.tv_nsec  = attr->mtimensec;
 135         inode->i_ctime.tv_sec   = attr->ctime;
 136         inode->i_ctime.tv_nsec  = attr->ctimensec;
 137
 138         spin_lock(&fc->lock);
 139         oldsize = inode->i_size;
 140         i_size_write(inode, attr->size);
 141         spin_unlock(&fc->lock);
 142
 143         if (S_ISREG(inode->i_mode) && oldsize != attr->size) {
 144                 if (attr->size < oldsize)
 145                         fuse_truncate(inode->i_mapping, attr->size);
 146                 invalidate_inode_pages2(inode->i_mapping);
 147         }
 148 }
 149
 150 static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
 151 {
 152         inode->i_mode = attr->mode & S_IFMT;
 153         inode->i_size = attr->size;
 154         if (S_ISREG(inode->i_mode)) {
 155                 fuse_init_common(inode);
 156                 fuse_init_file_inode(inode);
 157         } else if (S_ISDIR(inode->i_mode))
 158                 fuse_init_dir(inode);
 159         else if (S_ISLNK(inode->i_mode))
 160                 fuse_init_symlink(inode);
 161         else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
 162                  S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
 163                 fuse_init_common(inode);
 164                 init_special_inode(inode, inode->i_mode,
 165                                    new_decode_dev(attr->rdev));
 166         } else
 167                 BUG();
 168 }
 169
 170 static int fuse_inode_eq(struct inode *inode, void *_nodeidp)
 171 {
 172         unsigned long nodeid = *(unsigned long *) _nodeidp;
 173         if (get_node_id(inode) == nodeid)
 174                 return 1;
 175         else
 176                 return 0;
 177 }
 178
 179 static int fuse_inode_set(struct inode *inode, void *_nodeidp)
 180 {
 181         unsigned long nodeid = *(unsigned long *) _nodeidp;
 182         get_fuse_inode(inode)->nodeid = nodeid;
 183         return 0;
 184 }
 185
 186 struct inode *fuse_iget(struct super_block *sb, unsigned long nodeid,
 187                         int generation, struct fuse_attr *attr)
 188 {
 189         struct inode *inode;
 190         struct fuse_inode *fi;
 191         struct fuse_conn *fc = get_fuse_conn_super(sb);
 192
 193  retry:
 194         inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
 195         if (!inode)
 196                 return NULL;
 197
 198         if ((inode->i_state & I_NEW)) {
 199                 inode->i_flags |= S_NOATIME|S_NOCMTIME;
 200                 inode->i_generation = generation;
 201                 inode->i_data.backing_dev_info = &fc->bdi;
 202                 fuse_init_inode(inode, attr);
 203                 unlock_new_inode(inode);
 204         } else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
 205                 /* Inode has changed type, any I/O on the old should fail */
 206                 make_bad_inode(inode);
 207                 iput(inode);
 208                 goto retry;
 209         }
 210
 211         fi = get_fuse_inode(inode);
 212         spin_lock(&fc->lock);
 213         fi->nlookup ++;
 214         spin_unlock(&fc->lock);
 215         fuse_change_attributes(inode, attr);
 216         return inode;
 217 }
 218
 219 static void fuse_umount_begin(struct vfsmount *vfsmnt, int flags)
 220 {
 221         if (flags & MNT_FORCE)
 222                 fuse_abort_conn(get_fuse_conn_super(vfsmnt->mnt_sb));
 223 }
 224
 225 static void fuse_send_destroy(struct fuse_conn *fc)
 226 {
 227         struct fuse_req *req = fc->destroy_req;
 228         if (req && fc->conn_init) {
 229                 fc->destroy_req = NULL;
 230                 req->in.h.opcode = FUSE_DESTROY;
 231                 req->force = 1;
 232                 request_send(fc, req);
 233                 fuse_put_request(fc, req);
 234         }
 235 }
 236
 237 static void fuse_put_super(struct super_block *sb)
 238 {
 239         struct fuse_conn *fc = get_fuse_conn_super(sb);
 240
 241         fuse_send_destroy(fc);
 242         spin_lock(&fc->lock);
 243         fc->connected = 0;
 244         fc->blocked = 0;
 245         spin_unlock(&fc->lock);
 246         /* Flush all readers on this fs */
 247         kill_fasync(&fc->fasync, SIGIO, POLL_IN);
 248         wake_up_all(&fc->waitq);
 249         wake_up_all(&fc->blocked_waitq);
 250         wake_up_all(&fc->reserved_req_waitq);
 251         mutex_lock(&fuse_mutex);
 252         list_del(&fc->entry);
 253         fuse_ctl_remove_conn(fc);
 254         mutex_unlock(&fuse_mutex);
 255         fuse_conn_put(fc);
 256 }
 257
 258 static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
 259 {
 260         stbuf->f_type    = FUSE_SUPER_MAGIC;
 261         stbuf->f_bsize   = attr->bsize;
 262         stbuf->f_frsize  = attr->frsize;
 263         stbuf->f_blocks  = attr->blocks;
 264         stbuf->f_bfree   = attr->bfree;
 265         stbuf->f_bavail  = attr->bavail;
 266         stbuf->f_files   = attr->files;
 267         stbuf->f_ffree   = attr->ffree;
 268         stbuf->f_namelen = attr->namelen;
 269         /* fsid is left zero */
 270 }
 271
 272 static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
 273 {
 274         struct super_block *sb = dentry->d_sb;
 275         struct fuse_conn *fc = get_fuse_conn_super(sb);
 276         struct fuse_req *req;
 277         struct fuse_statfs_out outarg;
 278         int err;
 279
 280         req = fuse_get_req(fc);
 281         if (IS_ERR(req))
 282                 return PTR_ERR(req);
 283
 284         memset(&outarg, 0, sizeof(outarg));
 285         req->in.numargs = 0;
 286         req->in.h.opcode = FUSE_STATFS;
 287         req->in.h.nodeid = get_node_id(dentry->d_inode);
 288         req->out.numargs = 1;
 289         req->out.args[0].size =
 290                 fc->minor < 4 ? FUSE_COMPAT_STATFS_SIZE : sizeof(outarg);
 291         req->out.args[0].value = &outarg;
 292         request_send(fc, req);
 293         err = req->out.h.error;
 294         if (!err)
 295                 convert_fuse_statfs(buf, &outarg.st);
 296         fuse_put_request(fc, req);
 297         return err;
 298 }
 299
 300 enum {
 301         OPT_FD,
 302         OPT_ROOTMODE,
 303         OPT_USER_ID,
 304         OPT_GROUP_ID,
 305         OPT_DEFAULT_PERMISSIONS,
 306         OPT_ALLOW_OTHER,
 307         OPT_MAX_READ,
 308         OPT_BLKSIZE,
 309         OPT_ERR
 310 };
 311
 312 static match_table_t tokens = {
 313         {OPT_FD,                        "fd=%u"},
 314         {OPT_ROOTMODE,                  "rootmode=%o"},
 315         {OPT_USER_ID,                   "user_id=%u"},
 316         {OPT_GROUP_ID,                  "group_id=%u"},
 317         {OPT_DEFAULT_PERMISSIONS,       "default_permissions"},
 318         {OPT_ALLOW_OTHER,               "allow_other"},
 319         {OPT_MAX_READ,                  "max_read=%u"},
 320         {OPT_BLKSIZE,                   "blksize=%u"},
 321         {OPT_ERR,                       NULL}
 322 };
 323
 324 static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
 325 {
 326         char *p;
 327         memset(d, 0, sizeof(struct fuse_mount_data));
 328         d->max_read = ~0;
 329         d->blksize = 512;
 330
 331         while ((p = strsep(&opt, ",")) != NULL) {
 332                 int token;
 333                 int value;
 334                 substring_t args[MAX_OPT_ARGS];
 335                 if (!*p)
 336                         continue;
 337
 338                 token = match_token(p, tokens, args);
 339                 switch (token) {
 340                 case OPT_FD:
 341                         if (match_int(&args[0], &value))
 342                                 return 0;
 343                         d->fd = value;
 344                         d->fd_present = 1;
 345                         break;
 346
 347                 case OPT_ROOTMODE:
 348                         if (match_octal(&args[0], &value))
 349                                 return 0;
 350                         if (!fuse_valid_type(value))
 351                                 return 0;
 352                         d->rootmode = value;
 353                         d->rootmode_present = 1;
 354                         break;
 355
 356                 case OPT_USER_ID:
 357                         if (match_int(&args[0], &value))
 358                                 return 0;
 359                         d->user_id = value;
 360                         d->user_id_present = 1;
 361                         break;
 362
 363                 case OPT_GROUP_ID:
 364                         if (match_int(&args[0], &value))
 365                                 return 0;
 366                         d->group_id = value;
 367                         d->group_id_present = 1;
 368                         break;
 369
 370                 case OPT_DEFAULT_PERMISSIONS:
 371                         d->flags |= FUSE_DEFAULT_PERMISSIONS;
 372                         break;
 373
 374                 case OPT_ALLOW_OTHER:
 375                         d->flags |= FUSE_ALLOW_OTHER;
 376                         break;
 377
 378                 case OPT_MAX_READ:
 379                         if (match_int(&args[0], &value))
 380                                 return 0;
 381                         d->max_read = value;
 382                         break;
 383
 384                 case OPT_BLKSIZE:
 385                         if (!is_bdev || match_int(&args[0], &value))
 386                                 return 0;
 387                         d->blksize = value;
 388                         break;
 389
 390                 default:
 391                         return 0;
 392                 }
 393         }
 394
 395         if (!d->fd_present || !d->rootmode_present ||
 396             !d->user_id_present || !d->group_id_present)
 397                 return 0;
 398
 399         return 1;
 400 }
 401
 402 static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt)
 403 {
 404         struct fuse_conn *fc = get_fuse_conn_super(mnt->mnt_sb);
 405
 406         seq_printf(m, ",user_id=%u", fc->user_id);
 407         seq_printf(m, ",group_id=%u", fc->group_id);
 408         if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
 409                 seq_puts(m, ",default_permissions");
 410         if (fc->flags & FUSE_ALLOW_OTHER)
 411                 seq_puts(m, ",allow_other");
 412         if (fc->max_read != ~0)
 413                 seq_printf(m, ",max_read=%u", fc->max_read);
 414         return 0;
 415 }
 416
 417 static struct fuse_conn *new_conn(void)
 418 {
 419         struct fuse_conn *fc;
 420         int err;
 421
 422         fc = kzalloc(sizeof(*fc), GFP_KERNEL);
 423         if (fc) {
 424                 spin_lock_init(&fc->lock);
 425                 mutex_init(&fc->inst_mutex);
 426                 atomic_set(&fc->count, 1);
 427                 init_waitqueue_head(&fc->waitq);
 428                 init_waitqueue_head(&fc->blocked_waitq);
 429                 init_waitqueue_head(&fc->reserved_req_waitq);
 430                 INIT_LIST_HEAD(&fc->pending);
 431                 INIT_LIST_HEAD(&fc->processing);
 432                 INIT_LIST_HEAD(&fc->io);
 433                 INIT_LIST_HEAD(&fc->interrupts);
 434                 atomic_set(&fc->num_waiting, 0);
 435                 fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
 436                 fc->bdi.unplug_io_fn = default_unplug_io_fn;
 437                 err = bdi_init(&fc->bdi);
 438                 if (err) {
 439                         kfree(fc);
 440                         fc = NULL;
 441                         goto out;
 442                 }
 443                 fc->reqctr = 0;
 444                 fc->blocked = 1;
 445                 get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
 446         }
 447 out:
 448         return fc;
 449 }
 450
 451 void fuse_conn_put(struct fuse_conn *fc)
 452 {
 453         if (atomic_dec_and_test(&fc->count)) {
 454                 if (fc->destroy_req)
 455                         fuse_request_free(fc->destroy_req);
 456                 mutex_destroy(&fc->inst_mutex);
 457                 bdi_destroy(&fc->bdi);
 458                 kfree(fc);
 459         }
 460 }
 461
 462 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
 463 {
 464         atomic_inc(&fc->count);
 465         return fc;
 466 }
 467
 468 static struct inode *get_root_inode(struct super_block *sb, unsigned mode)
 469 {
 470         struct fuse_attr attr;
 471         memset(&attr, 0, sizeof(attr));
 472
 473         attr.mode = mode;
 474         attr.ino = FUSE_ROOT_ID;
 475         attr.nlink = 1;
 476         return fuse_iget(sb, 1, 0, &attr);
 477 }
 478
 479 static const struct super_operations fuse_super_operations = {
 480         .alloc_inode    = fuse_alloc_inode,
 481         .destroy_inode  = fuse_destroy_inode,
 482         .read_inode     = fuse_read_inode,
 483         .clear_inode    = fuse_clear_inode,
 484         .drop_inode     = generic_delete_inode,
 485         .remount_fs     = fuse_remount_fs,
 486         .put_super      = fuse_put_super,
 487         .umount_begin   = fuse_umount_begin,
 488         .statfs         = fuse_statfs,
 489         .show_options   = fuse_show_options,
 490 };
 491
 492 static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
 493 {
 494         struct fuse_init_out *arg = &req->misc.init_out;
 495
 496         if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION)
 497                 fc->conn_error = 1;
 498         else {
 499                 unsigned long ra_pages;
 500
 501                 if (arg->minor >= 6) {
 502                         ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
 503                         if (arg->flags & FUSE_ASYNC_READ)
 504                                 fc->async_read = 1;
 505                         if (!(arg->flags & FUSE_POSIX_LOCKS))
 506                                 fc->no_lock = 1;
 507                 } else {
 508                         ra_pages = fc->max_read / PAGE_CACHE_SIZE;
 509                         fc->no_lock = 1;
 510                 }
 511
 512                 fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
 513                 fc->minor = arg->minor;
 514                 fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
 515                 fc->conn_init = 1;
 516         }
 517         fuse_put_request(fc, req);
 518         fc->blocked = 0;
 519         wake_up_all(&fc->blocked_waitq);
 520 }
 521
 522 static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
 523 {
 524         struct fuse_init_in *arg = &req->misc.init_in;
 525
 526         arg->major = FUSE_KERNEL_VERSION;
 527         arg->minor = FUSE_KERNEL_MINOR_VERSION;
 528         arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
 529         arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS;
 530         req->in.h.opcode = FUSE_INIT;
 531         req->in.numargs = 1;
 532         req->in.args[0].size = sizeof(*arg);
 533         req->in.args[0].value = arg;
 534         req->out.numargs = 1;
 535         /* Variable length arguement used for backward compatibility
 536            with interface version < 7.5.  Rest of init_out is zeroed
 537            by do_get_request(), so a short reply is not a problem */
 538         req->out.argvar = 1;
 539         req->out.args[0].size = sizeof(struct fuse_init_out);
 540         req->out.args[0].value = &req->misc.init_out;
 541         req->end = process_init_reply;
 542         request_send_background(fc, req);
 543 }
 544
 545 static u64 conn_id(void)
 546 {
 547         static u64 ctr = 1;
 548         return ctr++;
 549 }
 550
 551 static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 552 {
 553         struct fuse_conn *fc;
 554         struct inode *root;
 555         struct fuse_mount_data d;
 556         struct file *file;
 557         struct dentry *root_dentry;
 558         struct fuse_req *init_req;
 559         int err;
 560         int is_bdev = sb->s_bdev != NULL;
 561
 562         if (sb->s_flags & MS_MANDLOCK)
 563                 return -EINVAL;
 564
 565         if (!parse_fuse_opt((char *) data, &d, is_bdev))
 566                 return -EINVAL;
 567
 568         if (is_bdev) {
 569 #ifdef CONFIG_BLOCK
 570                 if (!sb_set_blocksize(sb, d.blksize))
 571                         return -EINVAL;
 572 #endif
 573         } else {
 574                 sb->s_blocksize = PAGE_CACHE_SIZE;
 575                 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
 576         }
 577         sb->s_magic = FUSE_SUPER_MAGIC;
 578         sb->s_op = &fuse_super_operations;
 579         sb->s_maxbytes = MAX_LFS_FILESIZE;
 580
 581         file = fget(d.fd);
 582         if (!file)
 583                 return -EINVAL;
 584
 585         if (file->f_op != &fuse_dev_operations)
 586                 return -EINVAL;
 587
 588         fc = new_conn();
 589         if (!fc)
 590                 return -ENOMEM;
 591
 592         fc->flags = d.flags;
 593         fc->user_id = d.user_id;
 594         fc->group_id = d.group_id;
 595         fc->max_read = d.max_read;
 596
 597         /* Used by get_root_inode() */
 598         sb->s_fs_info = fc;
 599
 600         err = -ENOMEM;
 601         root = get_root_inode(sb, d.rootmode);
 602         if (!root)
 603                 goto err;
 604
 605         root_dentry = d_alloc_root(root);
 606         if (!root_dentry) {
 607                 iput(root);
 608                 goto err;
 609         }
 610
 611         init_req = fuse_request_alloc();
 612         if (!init_req)
 613                 goto err_put_root;
 614
 615         if (is_bdev) {
 616                 fc->destroy_req = fuse_request_alloc();
 617                 if (!fc->destroy_req)
 618                         goto err_put_root;
 619         }
 620
 621         mutex_lock(&fuse_mutex);
 622         err = -EINVAL;
 623         if (file->private_data)
 624                 goto err_unlock;
 625
 626         fc->id = conn_id();
 627         err = fuse_ctl_add_conn(fc);
 628         if (err)
 629                 goto err_unlock;
 630
 631         list_add_tail(&fc->entry, &fuse_conn_list);
 632         sb->s_root = root_dentry;
 633         fc->connected = 1;
 634         file->private_data = fuse_conn_get(fc);
 635         mutex_unlock(&fuse_mutex);
 636         /*
 637          * atomic_dec_and_test() in fput() provides the necessary
 638          * memory barrier for file->private_data to be visible on all
 639          * CPUs after this
 640          */
 641         fput(file);
 642
 643         fuse_send_init(fc, init_req);
 644
 645         return 0;
 646
 647  err_unlock:
 648         mutex_unlock(&fuse_mutex);
 649         fuse_request_free(init_req);
 650  err_put_root:
 651         dput(root_dentry);
 652  err:
 653         fput(file);
 654         fuse_conn_put(fc);
 655         return err;
 656 }
 657
 658 static int fuse_get_sb(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_nodev(fs_type, flags, raw_data, fuse_fill_super, mnt);
 663 }
 664
 665 static struct file_system_type fuse_fs_type = {
 666         .owner          = THIS_MODULE,
 667         .name           = "fuse",
 668         .fs_flags       = FS_HAS_SUBTYPE,
 669         .get_sb         = fuse_get_sb,
 670         .kill_sb        = kill_anon_super,
 671 };
 672
 673 #ifdef CONFIG_BLOCK
 674 static int fuse_get_sb_blk(struct file_system_type *fs_type,
 675                            int flags, const char *dev_name,
 676                            void *raw_data, struct vfsmount *mnt)
 677 {
 678         return get_sb_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super,
 679                            mnt);
 680 }
 681
 682 static struct file_system_type fuseblk_fs_type = {
 683         .owner          = THIS_MODULE,
 684         .name           = "fuseblk",
 685         .get_sb         = fuse_get_sb_blk,
 686         .kill_sb        = kill_block_super,
 687         .fs_flags       = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
 688 };
 689
 690 static inline int register_fuseblk(void)
 691 {
 692         return register_filesystem(&fuseblk_fs_type);
 693 }
 694
 695 static inline void unregister_fuseblk(void)
 696 {
 697         unregister_filesystem(&fuseblk_fs_type);
 698 }
 699 #else
 700 static inline int register_fuseblk(void)
 701 {
 702         return 0;
 703 }
 704
 705 static inline void unregister_fuseblk(void)
 706 {
 707 }
 708 #endif
 709
 710 static decl_subsys(fuse, NULL, NULL);
 711 static decl_subsys(connections, NULL, NULL);
 712
 713 static void fuse_inode_init_once(struct kmem_cache *cachep, void *foo)
 714 {
 715         struct inode * inode = foo;
 716
 717         inode_init_once(inode);
 718 }
 719
 720 static int __init fuse_fs_init(void)
 721 {
 722         int err;
 723
 724         err = register_filesystem(&fuse_fs_type);
 725         if (err)
 726                 goto out;
 727
 728         err = register_fuseblk();
 729         if (err)
 730                 goto out_unreg;
 731
 732         fuse_inode_cachep = kmem_cache_create("fuse_inode",
 733                                               sizeof(struct fuse_inode),
 734                                               0, SLAB_HWCACHE_ALIGN,
 735                                               fuse_inode_init_once);
 736         err = -ENOMEM;
 737         if (!fuse_inode_cachep)
 738                 goto out_unreg2;
 739
 740         return 0;
 741
 742  out_unreg2:
 743         unregister_fuseblk();
 744  out_unreg:
 745         unregister_filesystem(&fuse_fs_type);
 746  out:
 747         return err;
 748 }
 749
 750 static void fuse_fs_cleanup(void)
 751 {
 752         unregister_filesystem(&fuse_fs_type);
 753         unregister_fuseblk();
 754         kmem_cache_destroy(fuse_inode_cachep);
 755 }
 756
 757 static int fuse_sysfs_init(void)
 758 {
 759         int err;
 760
 761         kobj_set_kset_s(&fuse_subsys, fs_subsys);
 762         err = subsystem_register(&fuse_subsys);
 763         if (err)
 764                 goto out_err;
 765
 766         kobj_set_kset_s(&connections_subsys, fuse_subsys);
 767         err = subsystem_register(&connections_subsys);
 768         if (err)
 769                 goto out_fuse_unregister;
 770
 771         return 0;
 772
 773  out_fuse_unregister:
 774         subsystem_unregister(&fuse_subsys);
 775  out_err:
 776         return err;
 777 }
 778
 779 static void fuse_sysfs_cleanup(void)
 780 {
 781         subsystem_unregister(&connections_subsys);
 782         subsystem_unregister(&fuse_subsys);
 783 }
 784
 785 static int __init fuse_init(void)
 786 {
 787         int res;
 788
 789         printk("fuse init (API version %i.%i)\n",
 790                FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
 791
 792         INIT_LIST_HEAD(&fuse_conn_list);
 793         res = fuse_fs_init();
 794         if (res)
 795                 goto err;
 796
 797         res = fuse_dev_init();
 798         if (res)
 799                 goto err_fs_cleanup;
 800
 801         res = fuse_sysfs_init();
 802         if (res)
 803                 goto err_dev_cleanup;
 804
 805         res = fuse_ctl_init();
 806         if (res)
 807                 goto err_sysfs_cleanup;
 808
 809         return 0;
 810
 811  err_sysfs_cleanup:
 812         fuse_sysfs_cleanup();
 813  err_dev_cleanup:
 814         fuse_dev_cleanup();
 815  err_fs_cleanup:
 816         fuse_fs_cleanup();
 817  err:
 818         return res;
 819 }
 820
 821 static void __exit fuse_exit(void)
 822 {
 823         printk(KERN_DEBUG "fuse exit\n");
 824
 825         fuse_ctl_cleanup();
 826         fuse_sysfs_cleanup();
 827         fuse_fs_cleanup();
 828         fuse_dev_cleanup();
 829 }
 830
 831 module_init(fuse_init);
 832 module_exit(fuse_exit);