fs/hfsplus/super.c

   1 /*
   2  *  linux/fs/hfsplus/super.c
   3  *
   4  * Copyright (C) 2001
   5  * Brad Boyer (flar@allandria.com)
   6  * (C) 2003 Ardis Technologies <roman@ardistech.com>
   7  *
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/pagemap.h>
  13 #include <linux/fs.h>
  14 #include <linux/slab.h>
  15 #include <linux/vfs.h>
  16 #include <linux/nls.h>
  17
  18 static struct inode *hfsplus_alloc_inode(struct super_block *sb);
  19 static void hfsplus_destroy_inode(struct inode *inode);
  20
  21 #include "hfsplus_fs.h"
  22
  23 static int hfsplus_system_read_inode(struct inode *inode)
  24 {
  25         struct hfsplus_vh *vhdr = HFSPLUS_SB(inode->i_sb)->s_vhdr;
  26
  27         switch (inode->i_ino) {
  28         case HFSPLUS_EXT_CNID:
  29                 hfsplus_inode_read_fork(inode, &vhdr->ext_file);
  30                 inode->i_mapping->a_ops = &hfsplus_btree_aops;
  31                 break;
  32         case HFSPLUS_CAT_CNID:
  33                 hfsplus_inode_read_fork(inode, &vhdr->cat_file);
  34                 inode->i_mapping->a_ops = &hfsplus_btree_aops;
  35                 break;
  36         case HFSPLUS_ALLOC_CNID:
  37                 hfsplus_inode_read_fork(inode, &vhdr->alloc_file);
  38                 inode->i_mapping->a_ops = &hfsplus_aops;
  39                 break;
  40         case HFSPLUS_START_CNID:
  41                 hfsplus_inode_read_fork(inode, &vhdr->start_file);
  42                 break;
  43         case HFSPLUS_ATTR_CNID:
  44                 hfsplus_inode_read_fork(inode, &vhdr->attr_file);
  45                 inode->i_mapping->a_ops = &hfsplus_btree_aops;
  46                 break;
  47         default:
  48                 return -EIO;
  49         }
  50
  51         return 0;
  52 }
  53
  54 struct inode *hfsplus_iget(struct super_block *sb, unsigned long ino)
  55 {
  56         struct hfs_find_data fd;
  57         struct inode *inode;
  58         int err;
  59
  60         inode = iget_locked(sb, ino);
  61         if (!inode)
  62                 return ERR_PTR(-ENOMEM);
  63         if (!(inode->i_state & I_NEW))
  64                 return inode;
  65
  66         INIT_LIST_HEAD(&HFSPLUS_I(inode)->open_dir_list);
  67         mutex_init(&HFSPLUS_I(inode)->extents_lock);
  68         HFSPLUS_I(inode)->flags = 0;
  69         HFSPLUS_I(inode)->rsrc_inode = NULL;
  70         atomic_set(&HFSPLUS_I(inode)->opencnt, 0);
  71
  72         if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID ||
  73             inode->i_ino == HFSPLUS_ROOT_CNID) {
  74                 hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
  75                 err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
  76                 if (!err)
  77                         err = hfsplus_cat_read_inode(inode, &fd);
  78                 hfs_find_exit(&fd);
  79         } else {
  80                 err = hfsplus_system_read_inode(inode);
  81         }
  82
  83         if (err) {
  84                 iget_failed(inode);
  85                 return ERR_PTR(err);
  86         }
  87
  88         unlock_new_inode(inode);
  89         return inode;
  90 }
  91
  92 static int hfsplus_system_write_inode(struct inode *inode)
  93 {
  94         struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
  95         struct hfsplus_vh *vhdr = sbi->s_vhdr;
  96         struct hfsplus_fork_raw *fork;
  97         struct hfs_btree *tree = NULL;
  98
  99         switch (inode->i_ino) {
 100         case HFSPLUS_EXT_CNID:
 101                 fork = &vhdr->ext_file;
 102                 tree = sbi->ext_tree;
 103                 break;
 104         case HFSPLUS_CAT_CNID:
 105                 fork = &vhdr->cat_file;
 106                 tree = sbi->cat_tree;
 107                 break;
 108         case HFSPLUS_ALLOC_CNID:
 109                 fork = &vhdr->alloc_file;
 110                 break;
 111         case HFSPLUS_START_CNID:
 112                 fork = &vhdr->start_file;
 113                 break;
 114         case HFSPLUS_ATTR_CNID:
 115                 fork = &vhdr->attr_file;
 116                 tree = sbi->attr_tree;
 117         default:
 118                 return -EIO;
 119         }
 120
 121         if (fork->total_size != cpu_to_be64(inode->i_size)) {
 122                 sbi->flags |= HFSPLUS_SB_WRITEBACKUP;
 123                 inode->i_sb->s_dirt = 1;
 124         }
 125         hfsplus_inode_write_fork(inode, fork);
 126         if (tree)
 127                 hfs_btree_write(tree);
 128         return 0;
 129 }
 130
 131 static int hfsplus_write_inode(struct inode *inode,
 132                 struct writeback_control *wbc)
 133 {
 134         dprint(DBG_INODE, "hfsplus_write_inode: %lu\n", inode->i_ino);
 135
 136         hfsplus_ext_write_extent(inode);
 137
 138         if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID ||
 139             inode->i_ino == HFSPLUS_ROOT_CNID)
 140                 return hfsplus_cat_write_inode(inode);
 141         else
 142                 return hfsplus_system_write_inode(inode);
 143 }
 144
 145 static void hfsplus_evict_inode(struct inode *inode)
 146 {
 147         dprint(DBG_INODE, "hfsplus_evict_inode: %lu\n", inode->i_ino);
 148         truncate_inode_pages(&inode->i_data, 0);
 149         end_writeback(inode);
 150         if (HFSPLUS_IS_RSRC(inode)) {
 151                 HFSPLUS_I(HFSPLUS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
 152                 iput(HFSPLUS_I(inode)->rsrc_inode);
 153         }
 154 }
 155
 156 int hfsplus_sync_fs(struct super_block *sb, int wait)
 157 {
 158         struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 159         struct hfsplus_vh *vhdr = sbi->s_vhdr;
 160
 161         dprint(DBG_SUPER, "hfsplus_write_super\n");
 162
 163         mutex_lock(&sbi->alloc_mutex);
 164         sb->s_dirt = 0;
 165
 166         vhdr->free_blocks = cpu_to_be32(sbi->free_blocks);
 167         vhdr->next_alloc = cpu_to_be32(sbi->next_alloc);
 168         vhdr->next_cnid = cpu_to_be32(sbi->next_cnid);
 169         vhdr->folder_count = cpu_to_be32(sbi->folder_count);
 170         vhdr->file_count = cpu_to_be32(sbi->file_count);
 171
 172         mark_buffer_dirty(sbi->s_vhbh);
 173         if (sbi->flags & HFSPLUS_SB_WRITEBACKUP) {
 174                 if (sbi->sect_count) {
 175                         struct buffer_head *bh;
 176                         u32 block, offset;
 177
 178                         block = sbi->blockoffset;
 179                         block += (sbi->sect_count - 2) >> (sb->s_blocksize_bits - 9);
 180                         offset = ((sbi->sect_count - 2) << 9) & (sb->s_blocksize - 1);
 181                         printk(KERN_DEBUG "hfs: backup: %u,%u,%u,%u\n",
 182                                           sbi->blockoffset, sbi->sect_count,
 183                                           block, offset);
 184                         bh = sb_bread(sb, block);
 185                         if (bh) {
 186                                 vhdr = (struct hfsplus_vh *)(bh->b_data + offset);
 187                                 if (be16_to_cpu(vhdr->signature) == HFSPLUS_VOLHEAD_SIG) {
 188                                         memcpy(vhdr, sbi->s_vhdr, sizeof(*vhdr));
 189                                         mark_buffer_dirty(bh);
 190                                         brelse(bh);
 191                                 } else
 192                                         printk(KERN_WARNING "hfs: backup not found!\n");
 193                         }
 194                 }
 195                 sbi->flags &= ~HFSPLUS_SB_WRITEBACKUP;
 196         }
 197         mutex_unlock(&sbi->alloc_mutex);
 198         return 0;
 199 }
 200
 201 static void hfsplus_write_super(struct super_block *sb)
 202 {
 203         if (!(sb->s_flags & MS_RDONLY))
 204                 hfsplus_sync_fs(sb, 1);
 205         else
 206                 sb->s_dirt = 0;
 207 }
 208
 209 static void hfsplus_put_super(struct super_block *sb)
 210 {
 211         struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 212
 213         dprint(DBG_SUPER, "hfsplus_put_super\n");
 214
 215         if (!sb->s_fs_info)
 216                 return;
 217
 218         if (sb->s_dirt)
 219                 hfsplus_write_super(sb);
 220         if (!(sb->s_flags & MS_RDONLY) && sbi->s_vhdr) {
 221                 struct hfsplus_vh *vhdr = sbi->s_vhdr;
 222
 223                 vhdr->modify_date = hfsp_now2mt();
 224                 vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_UNMNT);
 225                 vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_INCNSTNT);
 226                 mark_buffer_dirty(sbi->s_vhbh);
 227                 sync_dirty_buffer(sbi->s_vhbh);
 228         }
 229
 230         hfs_btree_close(sbi->cat_tree);
 231         hfs_btree_close(sbi->ext_tree);
 232         iput(sbi->alloc_file);
 233         iput(sbi->hidden_dir);
 234         brelse(sbi->s_vhbh);
 235         unload_nls(sbi->nls);
 236         kfree(sb->s_fs_info);
 237         sb->s_fs_info = NULL;
 238 }
 239
 240 static int hfsplus_statfs(struct dentry *dentry, struct kstatfs *buf)
 241 {
 242         struct super_block *sb = dentry->d_sb;
 243         struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 244         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 245
 246         buf->f_type = HFSPLUS_SUPER_MAGIC;
 247         buf->f_bsize = sb->s_blocksize;
 248         buf->f_blocks = sbi->total_blocks << sbi->fs_shift;
 249         buf->f_bfree = sbi->free_blocks << sbi->fs_shift;
 250         buf->f_bavail = buf->f_bfree;
 251         buf->f_files = 0xFFFFFFFF;
 252         buf->f_ffree = 0xFFFFFFFF - sbi->next_cnid;
 253         buf->f_fsid.val[0] = (u32)id;
 254         buf->f_fsid.val[1] = (u32)(id >> 32);
 255         buf->f_namelen = HFSPLUS_MAX_STRLEN;
 256
 257         return 0;
 258 }
 259
 260 static int hfsplus_remount(struct super_block *sb, int *flags, char *data)
 261 {
 262         if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
 263                 return 0;
 264         if (!(*flags & MS_RDONLY)) {
 265                 struct hfsplus_vh *vhdr = HFSPLUS_SB(sb)->s_vhdr;
 266                 struct hfsplus_sb_info sbi;
 267
 268                 memset(&sbi, 0, sizeof(struct hfsplus_sb_info));
 269                 sbi.nls = HFSPLUS_SB(sb)->nls;
 270                 if (!hfsplus_parse_options(data, &sbi))
 271                         return -EINVAL;
 272
 273                 if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
 274                         printk(KERN_WARNING "hfs: filesystem was not cleanly unmounted, "
 275                                "running fsck.hfsplus is recommended.  leaving read-only.\n");
 276                         sb->s_flags |= MS_RDONLY;
 277                         *flags |= MS_RDONLY;
 278                 } else if (sbi.flags & HFSPLUS_SB_FORCE) {
 279                         /* nothing */
 280                 } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
 281                         printk(KERN_WARNING "hfs: filesystem is marked locked, leaving read-only.\n");
 282                         sb->s_flags |= MS_RDONLY;
 283                         *flags |= MS_RDONLY;
 284                 } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) {
 285                         printk(KERN_WARNING "hfs: filesystem is marked journaled, leaving read-only.\n");
 286                         sb->s_flags |= MS_RDONLY;
 287                         *flags |= MS_RDONLY;
 288                 }
 289         }
 290         return 0;
 291 }
 292
 293 static const struct super_operations hfsplus_sops = {
 294         .alloc_inode    = hfsplus_alloc_inode,
 295         .destroy_inode  = hfsplus_destroy_inode,
 296         .write_inode    = hfsplus_write_inode,
 297         .evict_inode    = hfsplus_evict_inode,
 298         .put_super      = hfsplus_put_super,
 299         .write_super    = hfsplus_write_super,
 300         .sync_fs        = hfsplus_sync_fs,
 301         .statfs         = hfsplus_statfs,
 302         .remount_fs     = hfsplus_remount,
 303         .show_options   = hfsplus_show_options,
 304 };
 305
 306 static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
 307 {
 308         struct hfsplus_vh *vhdr;
 309         struct hfsplus_sb_info *sbi;
 310         hfsplus_cat_entry entry;
 311         struct hfs_find_data fd;
 312         struct inode *root, *inode;
 313         struct qstr str;
 314         struct nls_table *nls = NULL;
 315         int err = -EINVAL;
 316
 317         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 318         if (!sbi)
 319                 return -ENOMEM;
 320
 321         sb->s_fs_info = sbi;
 322         INIT_HLIST_HEAD(&sbi->rsrc_inodes);
 323         mutex_init(&sbi->alloc_mutex);
 324         hfsplus_fill_defaults(sbi);
 325         if (!hfsplus_parse_options(data, sbi)) {
 326                 printk(KERN_ERR "hfs: unable to parse mount options\n");
 327                 err = -EINVAL;
 328                 goto cleanup;
 329         }
 330
 331         /* temporarily use utf8 to correctly find the hidden dir below */
 332         nls = sbi->nls;
 333         sbi->nls = load_nls("utf8");
 334         if (!sbi->nls) {
 335                 printk(KERN_ERR "hfs: unable to load nls for utf8\n");
 336                 err = -EINVAL;
 337                 goto cleanup;
 338         }
 339
 340         /* Grab the volume header */
 341         if (hfsplus_read_wrapper(sb)) {
 342                 if (!silent)
 343                         printk(KERN_WARNING "hfs: unable to find HFS+ superblock\n");
 344                 err = -EINVAL;
 345                 goto cleanup;
 346         }
 347         vhdr = sbi->s_vhdr;
 348
 349         /* Copy parts of the volume header into the superblock */
 350         sb->s_magic = HFSPLUS_VOLHEAD_SIG;
 351         if (be16_to_cpu(vhdr->version) < HFSPLUS_MIN_VERSION ||
 352             be16_to_cpu(vhdr->version) > HFSPLUS_CURRENT_VERSION) {
 353                 printk(KERN_ERR "hfs: wrong filesystem version\n");
 354                 goto cleanup;
 355         }
 356         sbi->total_blocks = be32_to_cpu(vhdr->total_blocks);
 357         sbi->free_blocks = be32_to_cpu(vhdr->free_blocks);
 358         sbi->next_alloc = be32_to_cpu(vhdr->next_alloc);
 359         sbi->next_cnid = be32_to_cpu(vhdr->next_cnid);
 360         sbi->file_count = be32_to_cpu(vhdr->file_count);
 361         sbi->folder_count = be32_to_cpu(vhdr->folder_count);
 362         sbi->data_clump_blocks =
 363                 be32_to_cpu(vhdr->data_clump_sz) >> sbi->alloc_blksz_shift;
 364         if (!sbi->data_clump_blocks)
 365                 sbi->data_clump_blocks = 1;
 366         sbi->rsrc_clump_blocks =
 367                 be32_to_cpu(vhdr->rsrc_clump_sz) >> sbi->alloc_blksz_shift;
 368         if (!sbi->rsrc_clump_blocks)
 369                 sbi->rsrc_clump_blocks = 1;
 370
 371         /* Set up operations so we can load metadata */
 372         sb->s_op = &hfsplus_sops;
 373         sb->s_maxbytes = MAX_LFS_FILESIZE;
 374
 375         if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
 376                 printk(KERN_WARNING "hfs: Filesystem was not cleanly unmounted, "
 377                        "running fsck.hfsplus is recommended.  mounting read-only.\n");
 378                 sb->s_flags |= MS_RDONLY;
 379         } else if (sbi->flags & HFSPLUS_SB_FORCE) {
 380                 /* nothing */
 381         } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
 382                 printk(KERN_WARNING "hfs: Filesystem is marked locked, mounting read-only.\n");
 383                 sb->s_flags |= MS_RDONLY;
 384         } else if ((vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) && !(sb->s_flags & MS_RDONLY)) {
 385                 printk(KERN_WARNING "hfs: write access to a journaled filesystem is not supported, "
 386                        "use the force option at your own risk, mounting read-only.\n");
 387                 sb->s_flags |= MS_RDONLY;
 388         }
 389         sbi->flags &= ~HFSPLUS_SB_FORCE;
 390
 391         /* Load metadata objects (B*Trees) */
 392         sbi->ext_tree = hfs_btree_open(sb, HFSPLUS_EXT_CNID);
 393         if (!sbi->ext_tree) {
 394                 printk(KERN_ERR "hfs: failed to load extents file\n");
 395                 goto cleanup;
 396         }
 397         sbi->cat_tree = hfs_btree_open(sb, HFSPLUS_CAT_CNID);
 398         if (!sbi->cat_tree) {
 399                 printk(KERN_ERR "hfs: failed to load catalog file\n");
 400                 goto cleanup;
 401         }
 402
 403         inode = hfsplus_iget(sb, HFSPLUS_ALLOC_CNID);
 404         if (IS_ERR(inode)) {
 405                 printk(KERN_ERR "hfs: failed to load allocation file\n");
 406                 err = PTR_ERR(inode);
 407                 goto cleanup;
 408         }
 409         sbi->alloc_file = inode;
 410
 411         /* Load the root directory */
 412         root = hfsplus_iget(sb, HFSPLUS_ROOT_CNID);
 413         if (IS_ERR(root)) {
 414                 printk(KERN_ERR "hfs: failed to load root directory\n");
 415                 err = PTR_ERR(root);
 416                 goto cleanup;
 417         }
 418         sb->s_root = d_alloc_root(root);
 419         if (!sb->s_root) {
 420                 iput(root);
 421                 err = -ENOMEM;
 422                 goto cleanup;
 423         }
 424         sb->s_root->d_op = &hfsplus_dentry_operations;
 425
 426         str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
 427         str.name = HFSP_HIDDENDIR_NAME;
 428         hfs_find_init(sbi->cat_tree, &fd);
 429         hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_ROOT_CNID, &str);
 430         if (!hfs_brec_read(&fd, &entry, sizeof(entry))) {
 431                 hfs_find_exit(&fd);
 432                 if (entry.type != cpu_to_be16(HFSPLUS_FOLDER))
 433                         goto cleanup;
 434                 inode = hfsplus_iget(sb, be32_to_cpu(entry.folder.id));
 435                 if (IS_ERR(inode)) {
 436                         err = PTR_ERR(inode);
 437                         goto cleanup;
 438                 }
 439                 sbi->hidden_dir = inode;
 440         } else
 441                 hfs_find_exit(&fd);
 442
 443         if (sb->s_flags & MS_RDONLY)
 444                 goto out;
 445
 446         /* H+LX == hfsplusutils, H+Lx == this driver, H+lx is unused
 447          * all three are registered with Apple for our use
 448          */
 449         vhdr->last_mount_vers = cpu_to_be32(HFSP_MOUNT_VERSION);
 450         vhdr->modify_date = hfsp_now2mt();
 451         be32_add_cpu(&vhdr->write_count, 1);
 452         vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_UNMNT);
 453         vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_INCNSTNT);
 454         mark_buffer_dirty(sbi->s_vhbh);
 455         sync_dirty_buffer(sbi->s_vhbh);
 456
 457         if (!sbi->hidden_dir) {
 458                 printk(KERN_DEBUG "hfs: create hidden dir...\n");
 459                 sbi->hidden_dir = hfsplus_new_inode(sb, S_IFDIR);
 460                 hfsplus_create_cat(sbi->hidden_dir->i_ino, sb->s_root->d_inode,
 461                                    &str, sbi->hidden_dir);
 462                 mark_inode_dirty(sbi->hidden_dir);
 463         }
 464 out:
 465         unload_nls(sbi->nls);
 466         sbi->nls = nls;
 467         return 0;
 468
 469 cleanup:
 470         hfsplus_put_super(sb);
 471         unload_nls(nls);
 472         return err;
 473 }
 474
 475 MODULE_AUTHOR("Brad Boyer");
 476 MODULE_DESCRIPTION("Extended Macintosh Filesystem");
 477 MODULE_LICENSE("GPL");
 478
 479 static struct kmem_cache *hfsplus_inode_cachep;
 480
 481 static struct inode *hfsplus_alloc_inode(struct super_block *sb)
 482 {
 483         struct hfsplus_inode_info *i;
 484
 485         i = kmem_cache_alloc(hfsplus_inode_cachep, GFP_KERNEL);
 486         return i ? &i->vfs_inode : NULL;
 487 }
 488
 489 static void hfsplus_destroy_inode(struct inode *inode)
 490 {
 491         kmem_cache_free(hfsplus_inode_cachep, HFSPLUS_I(inode));
 492 }
 493
 494 #define HFSPLUS_INODE_SIZE      sizeof(struct hfsplus_inode_info)
 495
 496 static int hfsplus_get_sb(struct file_system_type *fs_type,
 497                           int flags, const char *dev_name, void *data,
 498                           struct vfsmount *mnt)
 499 {
 500         return get_sb_bdev(fs_type, flags, dev_name, data, hfsplus_fill_super,
 501                            mnt);
 502 }
 503
 504 static struct file_system_type hfsplus_fs_type = {
 505         .owner          = THIS_MODULE,
 506         .name           = "hfsplus",
 507         .get_sb         = hfsplus_get_sb,
 508         .kill_sb        = kill_block_super,
 509         .fs_flags       = FS_REQUIRES_DEV,
 510 };
 511
 512 static void hfsplus_init_once(void *p)
 513 {
 514         struct hfsplus_inode_info *i = p;
 515
 516         inode_init_once(&i->vfs_inode);
 517 }
 518
 519 static int __init init_hfsplus_fs(void)
 520 {
 521         int err;
 522
 523         hfsplus_inode_cachep = kmem_cache_create("hfsplus_icache",
 524                 HFSPLUS_INODE_SIZE, 0, SLAB_HWCACHE_ALIGN,
 525                 hfsplus_init_once);
 526         if (!hfsplus_inode_cachep)
 527                 return -ENOMEM;
 528         err = register_filesystem(&hfsplus_fs_type);
 529         if (err)
 530                 kmem_cache_destroy(hfsplus_inode_cachep);
 531         return err;
 532 }
 533
 534 static void __exit exit_hfsplus_fs(void)
 535 {
 536         unregister_filesystem(&hfsplus_fs_type);
 537         kmem_cache_destroy(hfsplus_inode_cachep);
 538 }
 539
 540 module_init(init_hfsplus_fs)
 541 module_exit(exit_hfsplus_fs)