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/blkdev.h>
  14 #include <linux/fs.h>
  15 #include <linux/slab.h>
  16 #include <linux/vfs.h>
  17 #include <linux/nls.h>
  18
  19 static struct inode *hfsplus_alloc_inode(struct super_block *sb);
  20 static void hfsplus_destroy_inode(struct inode *inode);
  21
  22 #include "hfsplus_fs.h"
  23
  24 static int hfsplus_system_read_inode(struct inode *inode)
  25 {
  26         struct hfsplus_vh *vhdr = HFSPLUS_SB(inode->i_sb)->s_vhdr;
  27
  28         switch (inode->i_ino) {
  29         case HFSPLUS_EXT_CNID:
  30                 hfsplus_inode_read_fork(inode, &vhdr->ext_file);
  31                 inode->i_mapping->a_ops = &hfsplus_btree_aops;
  32                 break;
  33         case HFSPLUS_CAT_CNID:
  34                 hfsplus_inode_read_fork(inode, &vhdr->cat_file);
  35                 inode->i_mapping->a_ops = &hfsplus_btree_aops;
  36                 break;
  37         case HFSPLUS_ALLOC_CNID:
  38                 hfsplus_inode_read_fork(inode, &vhdr->alloc_file);
  39                 inode->i_mapping->a_ops = &hfsplus_aops;
  40                 break;
  41         case HFSPLUS_START_CNID:
  42                 hfsplus_inode_read_fork(inode, &vhdr->start_file);
  43                 break;
  44         case HFSPLUS_ATTR_CNID:
  45                 hfsplus_inode_read_fork(inode, &vhdr->attr_file);
  46                 inode->i_mapping->a_ops = &hfsplus_btree_aops;
  47                 break;
  48         default:
  49                 return -EIO;
  50         }
  51
  52         return 0;
  53 }
  54
  55 struct inode *hfsplus_iget(struct super_block *sb, unsigned long ino)
  56 {
  57         struct hfs_find_data fd;
  58         struct inode *inode;
  59         int err;
  60
  61         inode = iget_locked(sb, ino);
  62         if (!inode)
  63                 return ERR_PTR(-ENOMEM);
  64         if (!(inode->i_state & I_NEW))
  65                 return inode;
  66
  67         INIT_LIST_HEAD(&HFSPLUS_I(inode)->open_dir_list);
  68         mutex_init(&HFSPLUS_I(inode)->extents_lock);
  69         HFSPLUS_I(inode)->flags = 0;
  70         HFSPLUS_I(inode)->extent_state = 0;
  71         HFSPLUS_I(inode)->rsrc_inode = NULL;
  72         atomic_set(&HFSPLUS_I(inode)->opencnt, 0);
  73
  74         if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID ||
  75             inode->i_ino == HFSPLUS_ROOT_CNID) {
  76                 err = hfs_find_init(HFSPLUS_SB(inode->i_sb)->cat_tree, &fd);
  77                 if (!err) {
  78                         err = hfsplus_find_cat(inode->i_sb, inode->i_ino, &fd);
  79                         if (!err)
  80                                 err = hfsplus_cat_read_inode(inode, &fd);
  81                         hfs_find_exit(&fd);
  82                 }
  83         } else {
  84                 err = hfsplus_system_read_inode(inode);
  85         }
  86
  87         if (err) {
  88                 iget_failed(inode);
  89                 return ERR_PTR(err);
  90         }
  91
  92         unlock_new_inode(inode);
  93         return inode;
  94 }
  95
  96 static int hfsplus_system_write_inode(struct inode *inode)
  97 {
  98         struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
  99         struct hfsplus_vh *vhdr = sbi->s_vhdr;
 100         struct hfsplus_fork_raw *fork;
 101         struct hfs_btree *tree = NULL;
 102
 103         switch (inode->i_ino) {
 104         case HFSPLUS_EXT_CNID:
 105                 fork = &vhdr->ext_file;
 106                 tree = sbi->ext_tree;
 107                 break;
 108         case HFSPLUS_CAT_CNID:
 109                 fork = &vhdr->cat_file;
 110                 tree = sbi->cat_tree;
 111                 break;
 112         case HFSPLUS_ALLOC_CNID:
 113                 fork = &vhdr->alloc_file;
 114                 break;
 115         case HFSPLUS_START_CNID:
 116                 fork = &vhdr->start_file;
 117                 break;
 118         case HFSPLUS_ATTR_CNID:
 119                 fork = &vhdr->attr_file;
 120                 tree = sbi->attr_tree;
 121         default:
 122                 return -EIO;
 123         }
 124
 125         if (fork->total_size != cpu_to_be64(inode->i_size)) {
 126                 set_bit(HFSPLUS_SB_WRITEBACKUP, &sbi->flags);
 127                 inode->i_sb->s_dirt = 1;
 128         }
 129         hfsplus_inode_write_fork(inode, fork);
 130         if (tree)
 131                 hfs_btree_write(tree);
 132         return 0;
 133 }
 134
 135 static int hfsplus_write_inode(struct inode *inode,
 136                 struct writeback_control *wbc)
 137 {
 138         int err;
 139
 140         dprint(DBG_INODE, "hfsplus_write_inode: %lu\n", inode->i_ino);
 141
 142         err = hfsplus_ext_write_extent(inode);
 143         if (err)
 144                 return err;
 145
 146         if (inode->i_ino >= HFSPLUS_FIRSTUSER_CNID ||
 147             inode->i_ino == HFSPLUS_ROOT_CNID)
 148                 return hfsplus_cat_write_inode(inode);
 149         else
 150                 return hfsplus_system_write_inode(inode);
 151 }
 152
 153 static void hfsplus_evict_inode(struct inode *inode)
 154 {
 155         dprint(DBG_INODE, "hfsplus_evict_inode: %lu\n", inode->i_ino);
 156         truncate_inode_pages(&inode->i_data, 0);
 157         end_writeback(inode);
 158         if (HFSPLUS_IS_RSRC(inode)) {
 159                 HFSPLUS_I(HFSPLUS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
 160                 iput(HFSPLUS_I(inode)->rsrc_inode);
 161         }
 162 }
 163
 164 int hfsplus_sync_fs(struct super_block *sb, int wait)
 165 {
 166         struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 167         struct hfsplus_vh *vhdr = sbi->s_vhdr;
 168         int write_backup = 0;
 169         int error, error2;
 170
 171         if (!wait)
 172                 return 0;
 173
 174         dprint(DBG_SUPER, "hfsplus_write_super\n");
 175
 176         sb->s_dirt = 0;
 177
 178         /*
 179          * Explicitly write out the special metadata inodes.
 180          *
 181          * While these special inodes are marked as hashed and written
 182          * out peridocically by the flusher threads we redirty them
 183          * during writeout of normal inodes, and thus the life lock
 184          * prevents us from getting the latest state to disk.
 185          */
 186         error = filemap_write_and_wait(sbi->cat_tree->inode->i_mapping);
 187         error2 = filemap_write_and_wait(sbi->ext_tree->inode->i_mapping);
 188         if (!error)
 189                 error = error2;
 190         error2 = filemap_write_and_wait(sbi->alloc_file->i_mapping);
 191         if (!error)
 192                 error = error2;
 193
 194         mutex_lock(&sbi->vh_mutex);
 195         mutex_lock(&sbi->alloc_mutex);
 196         vhdr->free_blocks = cpu_to_be32(sbi->free_blocks);
 197         vhdr->next_cnid = cpu_to_be32(sbi->next_cnid);
 198         vhdr->folder_count = cpu_to_be32(sbi->folder_count);
 199         vhdr->file_count = cpu_to_be32(sbi->file_count);
 200
 201         if (test_and_clear_bit(HFSPLUS_SB_WRITEBACKUP, &sbi->flags)) {
 202                 memcpy(sbi->s_backup_vhdr, sbi->s_vhdr, sizeof(*sbi->s_vhdr));
 203                 write_backup = 1;
 204         }
 205
 206         error2 = hfsplus_submit_bio(sb,
 207                                    sbi->part_start + HFSPLUS_VOLHEAD_SECTOR,
 208                                    sbi->s_vhdr_buf, NULL, WRITE_SYNC);
 209         if (!error)
 210                 error = error2;
 211         if (!write_backup)
 212                 goto out;
 213
 214         error2 = hfsplus_submit_bio(sb,
 215                                   sbi->part_start + sbi->sect_count - 2,
 216                                   sbi->s_backup_vhdr_buf, NULL, WRITE_SYNC);
 217         if (!error)
 218                 error2 = error;
 219 out:
 220         mutex_unlock(&sbi->alloc_mutex);
 221         mutex_unlock(&sbi->vh_mutex);
 222
 223         if (!test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags))
 224                 blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
 225
 226         return error;
 227 }
 228
 229 static void hfsplus_write_super(struct super_block *sb)
 230 {
 231         if (!(sb->s_flags & MS_RDONLY))
 232                 hfsplus_sync_fs(sb, 1);
 233         else
 234                 sb->s_dirt = 0;
 235 }
 236
 237 static void hfsplus_put_super(struct super_block *sb)
 238 {
 239         struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 240
 241         dprint(DBG_SUPER, "hfsplus_put_super\n");
 242
 243         if (!sb->s_fs_info)
 244                 return;
 245
 246         if (!(sb->s_flags & MS_RDONLY) && sbi->s_vhdr) {
 247                 struct hfsplus_vh *vhdr = sbi->s_vhdr;
 248
 249                 vhdr->modify_date = hfsp_now2mt();
 250                 vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_UNMNT);
 251                 vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_INCNSTNT);
 252
 253                 hfsplus_sync_fs(sb, 1);
 254         }
 255
 256         hfs_btree_close(sbi->cat_tree);
 257         hfs_btree_close(sbi->ext_tree);
 258         iput(sbi->alloc_file);
 259         iput(sbi->hidden_dir);
 260         kfree(sbi->s_vhdr_buf);
 261         kfree(sbi->s_backup_vhdr_buf);
 262         unload_nls(sbi->nls);
 263         kfree(sb->s_fs_info);
 264         sb->s_fs_info = NULL;
 265 }
 266
 267 static int hfsplus_statfs(struct dentry *dentry, struct kstatfs *buf)
 268 {
 269         struct super_block *sb = dentry->d_sb;
 270         struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 271         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 272
 273         buf->f_type = HFSPLUS_SUPER_MAGIC;
 274         buf->f_bsize = sb->s_blocksize;
 275         buf->f_blocks = sbi->total_blocks << sbi->fs_shift;
 276         buf->f_bfree = sbi->free_blocks << sbi->fs_shift;
 277         buf->f_bavail = buf->f_bfree;
 278         buf->f_files = 0xFFFFFFFF;
 279         buf->f_ffree = 0xFFFFFFFF - sbi->next_cnid;
 280         buf->f_fsid.val[0] = (u32)id;
 281         buf->f_fsid.val[1] = (u32)(id >> 32);
 282         buf->f_namelen = HFSPLUS_MAX_STRLEN;
 283
 284         return 0;
 285 }
 286
 287 static int hfsplus_remount(struct super_block *sb, int *flags, char *data)
 288 {
 289         if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
 290                 return 0;
 291         if (!(*flags & MS_RDONLY)) {
 292                 struct hfsplus_vh *vhdr = HFSPLUS_SB(sb)->s_vhdr;
 293                 int force = 0;
 294
 295                 if (!hfsplus_parse_options_remount(data, &force))
 296                         return -EINVAL;
 297
 298                 if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
 299                         printk(KERN_WARNING "hfs: filesystem was "
 300                                         "not cleanly unmounted, "
 301                                         "running fsck.hfsplus is recommended.  "
 302                                         "leaving read-only.\n");
 303                         sb->s_flags |= MS_RDONLY;
 304                         *flags |= MS_RDONLY;
 305                 } else if (force) {
 306                         /* nothing */
 307                 } else if (vhdr->attributes &
 308                                 cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
 309                         printk(KERN_WARNING "hfs: filesystem is marked locked, "
 310                                         "leaving read-only.\n");
 311                         sb->s_flags |= MS_RDONLY;
 312                         *flags |= MS_RDONLY;
 313                 } else if (vhdr->attributes &
 314                                 cpu_to_be32(HFSPLUS_VOL_JOURNALED)) {
 315                         printk(KERN_WARNING "hfs: filesystem is "
 316                                         "marked journaled, "
 317                                         "leaving read-only.\n");
 318                         sb->s_flags |= MS_RDONLY;
 319                         *flags |= MS_RDONLY;
 320                 }
 321         }
 322         return 0;
 323 }
 324
 325 static const struct super_operations hfsplus_sops = {
 326         .alloc_inode    = hfsplus_alloc_inode,
 327         .destroy_inode  = hfsplus_destroy_inode,
 328         .write_inode    = hfsplus_write_inode,
 329         .evict_inode    = hfsplus_evict_inode,
 330         .put_super      = hfsplus_put_super,
 331         .write_super    = hfsplus_write_super,
 332         .sync_fs        = hfsplus_sync_fs,
 333         .statfs         = hfsplus_statfs,
 334         .remount_fs     = hfsplus_remount,
 335         .show_options   = hfsplus_show_options,
 336 };
 337
 338 static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
 339 {
 340         struct hfsplus_vh *vhdr;
 341         struct hfsplus_sb_info *sbi;
 342         hfsplus_cat_entry entry;
 343         struct hfs_find_data fd;
 344         struct inode *root, *inode;
 345         struct qstr str;
 346         struct nls_table *nls = NULL;
 347         u64 last_fs_block, last_fs_page;
 348         int err;
 349
 350         err = -EINVAL;
 351         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 352         if (!sbi)
 353                 goto out;
 354
 355         sb->s_fs_info = sbi;
 356         mutex_init(&sbi->alloc_mutex);
 357         mutex_init(&sbi->vh_mutex);
 358         hfsplus_fill_defaults(sbi);
 359
 360         err = -EINVAL;
 361         if (!hfsplus_parse_options(data, sbi)) {
 362                 printk(KERN_ERR "hfs: unable to parse mount options\n");
 363                 goto out_unload_nls;
 364         }
 365
 366         /* temporarily use utf8 to correctly find the hidden dir below */
 367         nls = sbi->nls;
 368         sbi->nls = load_nls("utf8");
 369         if (!sbi->nls) {
 370                 printk(KERN_ERR "hfs: unable to load nls for utf8\n");
 371                 goto out_unload_nls;
 372         }
 373
 374         /* Grab the volume header */
 375         if (hfsplus_read_wrapper(sb)) {
 376                 if (!silent)
 377                         printk(KERN_WARNING "hfs: unable to find HFS+ superblock\n");
 378                 goto out_unload_nls;
 379         }
 380         vhdr = sbi->s_vhdr;
 381
 382         /* Copy parts of the volume header into the superblock */
 383         sb->s_magic = HFSPLUS_VOLHEAD_SIG;
 384         if (be16_to_cpu(vhdr->version) < HFSPLUS_MIN_VERSION ||
 385             be16_to_cpu(vhdr->version) > HFSPLUS_CURRENT_VERSION) {
 386                 printk(KERN_ERR "hfs: wrong filesystem version\n");
 387                 goto out_free_vhdr;
 388         }
 389         sbi->total_blocks = be32_to_cpu(vhdr->total_blocks);
 390         sbi->free_blocks = be32_to_cpu(vhdr->free_blocks);
 391         sbi->next_cnid = be32_to_cpu(vhdr->next_cnid);
 392         sbi->file_count = be32_to_cpu(vhdr->file_count);
 393         sbi->folder_count = be32_to_cpu(vhdr->folder_count);
 394         sbi->data_clump_blocks =
 395                 be32_to_cpu(vhdr->data_clump_sz) >> sbi->alloc_blksz_shift;
 396         if (!sbi->data_clump_blocks)
 397                 sbi->data_clump_blocks = 1;
 398         sbi->rsrc_clump_blocks =
 399                 be32_to_cpu(vhdr->rsrc_clump_sz) >> sbi->alloc_blksz_shift;
 400         if (!sbi->rsrc_clump_blocks)
 401                 sbi->rsrc_clump_blocks = 1;
 402
 403         err = -EFBIG;
 404         last_fs_block = sbi->total_blocks - 1;
 405         last_fs_page = (last_fs_block << sbi->alloc_blksz_shift) >>
 406                         PAGE_CACHE_SHIFT;
 407
 408         if ((last_fs_block > (sector_t)(~0ULL) >> (sbi->alloc_blksz_shift - 9)) ||
 409             (last_fs_page > (pgoff_t)(~0ULL))) {
 410                 printk(KERN_ERR "hfs: filesystem size too large.\n");
 411                 goto out_free_vhdr;
 412         }
 413
 414         /* Set up operations so we can load metadata */
 415         sb->s_op = &hfsplus_sops;
 416         sb->s_maxbytes = MAX_LFS_FILESIZE;
 417
 418         if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
 419                 printk(KERN_WARNING "hfs: Filesystem was "
 420                                 "not cleanly unmounted, "
 421                                 "running fsck.hfsplus is recommended.  "
 422                                 "mounting read-only.\n");
 423                 sb->s_flags |= MS_RDONLY;
 424         } else if (test_and_clear_bit(HFSPLUS_SB_FORCE, &sbi->flags)) {
 425                 /* nothing */
 426         } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
 427                 printk(KERN_WARNING "hfs: Filesystem is marked locked, mounting read-only.\n");
 428                 sb->s_flags |= MS_RDONLY;
 429         } else if ((vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) &&
 430                         !(sb->s_flags & MS_RDONLY)) {
 431                 printk(KERN_WARNING "hfs: write access to "
 432                                 "a journaled filesystem is not supported, "
 433                                 "use the force option at your own risk, "
 434                                 "mounting read-only.\n");
 435                 sb->s_flags |= MS_RDONLY;
 436         }
 437
 438         err = -EINVAL;
 439
 440         /* Load metadata objects (B*Trees) */
 441         sbi->ext_tree = hfs_btree_open(sb, HFSPLUS_EXT_CNID);
 442         if (!sbi->ext_tree) {
 443                 printk(KERN_ERR "hfs: failed to load extents file\n");
 444                 goto out_free_vhdr;
 445         }
 446         sbi->cat_tree = hfs_btree_open(sb, HFSPLUS_CAT_CNID);
 447         if (!sbi->cat_tree) {
 448                 printk(KERN_ERR "hfs: failed to load catalog file\n");
 449                 goto out_close_ext_tree;
 450         }
 451
 452         inode = hfsplus_iget(sb, HFSPLUS_ALLOC_CNID);
 453         if (IS_ERR(inode)) {
 454                 printk(KERN_ERR "hfs: failed to load allocation file\n");
 455                 err = PTR_ERR(inode);
 456                 goto out_close_cat_tree;
 457         }
 458         sbi->alloc_file = inode;
 459
 460         /* Load the root directory */
 461         root = hfsplus_iget(sb, HFSPLUS_ROOT_CNID);
 462         if (IS_ERR(root)) {
 463                 printk(KERN_ERR "hfs: failed to load root directory\n");
 464                 err = PTR_ERR(root);
 465                 goto out_put_alloc_file;
 466         }
 467
 468         str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
 469         str.name = HFSP_HIDDENDIR_NAME;
 470         err = hfs_find_init(sbi->cat_tree, &fd);
 471         if (err)
 472                 goto out_put_root;
 473         hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_ROOT_CNID, &str);
 474         if (!hfs_brec_read(&fd, &entry, sizeof(entry))) {
 475                 hfs_find_exit(&fd);
 476                 if (entry.type != cpu_to_be16(HFSPLUS_FOLDER))
 477                         goto out_put_root;
 478                 inode = hfsplus_iget(sb, be32_to_cpu(entry.folder.id));
 479                 if (IS_ERR(inode)) {
 480                         err = PTR_ERR(inode);
 481                         goto out_put_root;
 482                 }
 483                 sbi->hidden_dir = inode;
 484         } else
 485                 hfs_find_exit(&fd);
 486
 487         if (!(sb->s_flags & MS_RDONLY)) {
 488                 /*
 489                  * H+LX == hfsplusutils, H+Lx == this driver, H+lx is unused
 490                  * all three are registered with Apple for our use
 491                  */
 492                 vhdr->last_mount_vers = cpu_to_be32(HFSP_MOUNT_VERSION);
 493                 vhdr->modify_date = hfsp_now2mt();
 494                 be32_add_cpu(&vhdr->write_count, 1);
 495                 vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_UNMNT);
 496                 vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_INCNSTNT);
 497                 hfsplus_sync_fs(sb, 1);
 498
 499                 if (!sbi->hidden_dir) {
 500                         mutex_lock(&sbi->vh_mutex);
 501                         sbi->hidden_dir = hfsplus_new_inode(sb, S_IFDIR);
 502                         if (!sbi->hidden_dir) {
 503                                 mutex_unlock(&sbi->vh_mutex);
 504                                 err = -ENOMEM;
 505                                 goto out_put_root;
 506                         }
 507                         err = hfsplus_create_cat(sbi->hidden_dir->i_ino, root,
 508                                                  &str, sbi->hidden_dir);
 509                         mutex_unlock(&sbi->vh_mutex);
 510                         if (err)
 511                                 goto out_put_hidden_dir;
 512
 513                         hfsplus_mark_inode_dirty(sbi->hidden_dir,
 514                                                  HFSPLUS_I_CAT_DIRTY);
 515                 }
 516         }
 517
 518         sb->s_d_op = &hfsplus_dentry_operations;
 519         sb->s_root = d_alloc_root(root);
 520         if (!sb->s_root) {
 521                 err = -ENOMEM;
 522                 goto out_put_hidden_dir;
 523         }
 524
 525         unload_nls(sbi->nls);
 526         sbi->nls = nls;
 527         return 0;
 528
 529 out_put_hidden_dir:
 530         iput(sbi->hidden_dir);
 531 out_put_root:
 532         iput(root);
 533 out_put_alloc_file:
 534         iput(sbi->alloc_file);
 535 out_close_cat_tree:
 536         hfs_btree_close(sbi->cat_tree);
 537 out_close_ext_tree:
 538         hfs_btree_close(sbi->ext_tree);
 539 out_free_vhdr:
 540         kfree(sbi->s_vhdr_buf);
 541         kfree(sbi->s_backup_vhdr_buf);
 542 out_unload_nls:
 543         unload_nls(sbi->nls);
 544         unload_nls(nls);
 545         kfree(sbi);
 546 out:
 547         return err;
 548 }
 549
 550 MODULE_AUTHOR("Brad Boyer");
 551 MODULE_DESCRIPTION("Extended Macintosh Filesystem");
 552 MODULE_LICENSE("GPL");
 553
 554 static struct kmem_cache *hfsplus_inode_cachep;
 555
 556 static struct inode *hfsplus_alloc_inode(struct super_block *sb)
 557 {
 558         struct hfsplus_inode_info *i;
 559
 560         i = kmem_cache_alloc(hfsplus_inode_cachep, GFP_KERNEL);
 561         return i ? &i->vfs_inode : NULL;
 562 }
 563
 564 static void hfsplus_i_callback(struct rcu_head *head)
 565 {
 566         struct inode *inode = container_of(head, struct inode, i_rcu);
 567
 568         kmem_cache_free(hfsplus_inode_cachep, HFSPLUS_I(inode));
 569 }
 570
 571 static void hfsplus_destroy_inode(struct inode *inode)
 572 {
 573         call_rcu(&inode->i_rcu, hfsplus_i_callback);
 574 }
 575
 576 #define HFSPLUS_INODE_SIZE      sizeof(struct hfsplus_inode_info)
 577
 578 static struct dentry *hfsplus_mount(struct file_system_type *fs_type,
 579                           int flags, const char *dev_name, void *data)
 580 {
 581         return mount_bdev(fs_type, flags, dev_name, data, hfsplus_fill_super);
 582 }
 583
 584 static struct file_system_type hfsplus_fs_type = {
 585         .owner          = THIS_MODULE,
 586         .name           = "hfsplus",
 587         .mount          = hfsplus_mount,
 588         .kill_sb        = kill_block_super,
 589         .fs_flags       = FS_REQUIRES_DEV,
 590 };
 591
 592 static void hfsplus_init_once(void *p)
 593 {
 594         struct hfsplus_inode_info *i = p;
 595
 596         inode_init_once(&i->vfs_inode);
 597 }
 598
 599 static int __init init_hfsplus_fs(void)
 600 {
 601         int err;
 602
 603         hfsplus_inode_cachep = kmem_cache_create("hfsplus_icache",
 604                 HFSPLUS_INODE_SIZE, 0, SLAB_HWCACHE_ALIGN,
 605                 hfsplus_init_once);
 606         if (!hfsplus_inode_cachep)
 607                 return -ENOMEM;
 608         err = register_filesystem(&hfsplus_fs_type);
 609         if (err)
 610                 kmem_cache_destroy(hfsplus_inode_cachep);
 611         return err;
 612 }
 613
 614 static void __exit exit_hfsplus_fs(void)
 615 {
 616         unregister_filesystem(&hfsplus_fs_type);
 617         kmem_cache_destroy(hfsplus_inode_cachep);
 618 }
 619
 620 module_init(init_hfsplus_fs)
 621 module_exit(exit_hfsplus_fs)