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_cnid = cpu_to_be32(sbi->next_cnid);
 168         vhdr->folder_count = cpu_to_be32(sbi->folder_count);
 169         vhdr->file_count = cpu_to_be32(sbi->file_count);
 170
 171         mark_buffer_dirty(sbi->s_vhbh);
 172         if (sbi->flags & HFSPLUS_SB_WRITEBACKUP) {
 173                 if (sbi->sect_count) {
 174                         struct buffer_head *bh;
 175                         u32 block, offset;
 176
 177                         block = sbi->blockoffset;
 178                         block += (sbi->sect_count - 2) >> (sb->s_blocksize_bits - 9);
 179                         offset = ((sbi->sect_count - 2) << 9) & (sb->s_blocksize - 1);
 180                         printk(KERN_DEBUG "hfs: backup: %u,%u,%u,%u\n",
 181                                           sbi->blockoffset, sbi->sect_count,
 182                                           block, offset);
 183                         bh = sb_bread(sb, block);
 184                         if (bh) {
 185                                 vhdr = (struct hfsplus_vh *)(bh->b_data + offset);
 186                                 if (be16_to_cpu(vhdr->signature) == HFSPLUS_VOLHEAD_SIG) {
 187                                         memcpy(vhdr, sbi->s_vhdr, sizeof(*vhdr));
 188                                         mark_buffer_dirty(bh);
 189                                         brelse(bh);
 190                                 } else
 191                                         printk(KERN_WARNING "hfs: backup not found!\n");
 192                         }
 193                 }
 194                 sbi->flags &= ~HFSPLUS_SB_WRITEBACKUP;
 195         }
 196         mutex_unlock(&sbi->alloc_mutex);
 197         return 0;
 198 }
 199
 200 static void hfsplus_write_super(struct super_block *sb)
 201 {
 202         if (!(sb->s_flags & MS_RDONLY))
 203                 hfsplus_sync_fs(sb, 1);
 204         else
 205                 sb->s_dirt = 0;
 206 }
 207
 208 static void hfsplus_put_super(struct super_block *sb)
 209 {
 210         struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 211
 212         dprint(DBG_SUPER, "hfsplus_put_super\n");
 213
 214         if (!sb->s_fs_info)
 215                 return;
 216
 217         if (sb->s_dirt)
 218                 hfsplus_write_super(sb);
 219         if (!(sb->s_flags & MS_RDONLY) && sbi->s_vhdr) {
 220                 struct hfsplus_vh *vhdr = sbi->s_vhdr;
 221
 222                 vhdr->modify_date = hfsp_now2mt();
 223                 vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_UNMNT);
 224                 vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_INCNSTNT);
 225                 mark_buffer_dirty(sbi->s_vhbh);
 226                 sync_dirty_buffer(sbi->s_vhbh);
 227         }
 228
 229         hfs_btree_close(sbi->cat_tree);
 230         hfs_btree_close(sbi->ext_tree);
 231         iput(sbi->alloc_file);
 232         iput(sbi->hidden_dir);
 233         brelse(sbi->s_vhbh);
 234         unload_nls(sbi->nls);
 235         kfree(sb->s_fs_info);
 236         sb->s_fs_info = NULL;
 237 }
 238
 239 static int hfsplus_statfs(struct dentry *dentry, struct kstatfs *buf)
 240 {
 241         struct super_block *sb = dentry->d_sb;
 242         struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 243         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 244
 245         buf->f_type = HFSPLUS_SUPER_MAGIC;
 246         buf->f_bsize = sb->s_blocksize;
 247         buf->f_blocks = sbi->total_blocks << sbi->fs_shift;
 248         buf->f_bfree = sbi->free_blocks << sbi->fs_shift;
 249         buf->f_bavail = buf->f_bfree;
 250         buf->f_files = 0xFFFFFFFF;
 251         buf->f_ffree = 0xFFFFFFFF - sbi->next_cnid;
 252         buf->f_fsid.val[0] = (u32)id;
 253         buf->f_fsid.val[1] = (u32)(id >> 32);
 254         buf->f_namelen = HFSPLUS_MAX_STRLEN;
 255
 256         return 0;
 257 }
 258
 259 static int hfsplus_remount(struct super_block *sb, int *flags, char *data)
 260 {
 261         if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
 262                 return 0;
 263         if (!(*flags & MS_RDONLY)) {
 264                 struct hfsplus_vh *vhdr = HFSPLUS_SB(sb)->s_vhdr;
 265                 struct hfsplus_sb_info sbi;
 266
 267                 memset(&sbi, 0, sizeof(struct hfsplus_sb_info));
 268                 sbi.nls = HFSPLUS_SB(sb)->nls;
 269                 if (!hfsplus_parse_options(data, &sbi))
 270                         return -EINVAL;
 271
 272                 if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
 273                         printk(KERN_WARNING "hfs: filesystem was not cleanly unmounted, "
 274                                "running fsck.hfsplus is recommended.  leaving read-only.\n");
 275                         sb->s_flags |= MS_RDONLY;
 276                         *flags |= MS_RDONLY;
 277                 } else if (sbi.flags & HFSPLUS_SB_FORCE) {
 278                         /* nothing */
 279                 } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
 280                         printk(KERN_WARNING "hfs: filesystem is marked locked, leaving read-only.\n");
 281                         sb->s_flags |= MS_RDONLY;
 282                         *flags |= MS_RDONLY;
 283                 } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) {
 284                         printk(KERN_WARNING "hfs: filesystem is marked journaled, leaving read-only.\n");
 285                         sb->s_flags |= MS_RDONLY;
 286                         *flags |= MS_RDONLY;
 287                 }
 288         }
 289         return 0;
 290 }
 291
 292 static const struct super_operations hfsplus_sops = {
 293         .alloc_inode    = hfsplus_alloc_inode,
 294         .destroy_inode  = hfsplus_destroy_inode,
 295         .write_inode    = hfsplus_write_inode,
 296         .evict_inode    = hfsplus_evict_inode,
 297         .put_super      = hfsplus_put_super,
 298         .write_super    = hfsplus_write_super,
 299         .sync_fs        = hfsplus_sync_fs,
 300         .statfs         = hfsplus_statfs,
 301         .remount_fs     = hfsplus_remount,
 302         .show_options   = hfsplus_show_options,
 303 };
 304
 305 static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
 306 {
 307         struct hfsplus_vh *vhdr;
 308         struct hfsplus_sb_info *sbi;
 309         hfsplus_cat_entry entry;
 310         struct hfs_find_data fd;
 311         struct inode *root, *inode;
 312         struct qstr str;
 313         struct nls_table *nls = NULL;
 314         int err = -EINVAL;
 315
 316         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 317         if (!sbi)
 318                 return -ENOMEM;
 319
 320         sb->s_fs_info = sbi;
 321         INIT_HLIST_HEAD(&sbi->rsrc_inodes);
 322         mutex_init(&sbi->alloc_mutex);
 323         hfsplus_fill_defaults(sbi);
 324         if (!hfsplus_parse_options(data, sbi)) {
 325                 printk(KERN_ERR "hfs: unable to parse mount options\n");
 326                 err = -EINVAL;
 327                 goto cleanup;
 328         }
 329
 330         /* temporarily use utf8 to correctly find the hidden dir below */
 331         nls = sbi->nls;
 332         sbi->nls = load_nls("utf8");
 333         if (!sbi->nls) {
 334                 printk(KERN_ERR "hfs: unable to load nls for utf8\n");
 335                 err = -EINVAL;
 336                 goto cleanup;
 337         }
 338
 339         /* Grab the volume header */
 340         if (hfsplus_read_wrapper(sb)) {
 341                 if (!silent)
 342                         printk(KERN_WARNING "hfs: unable to find HFS+ superblock\n");
 343                 err = -EINVAL;
 344                 goto cleanup;
 345         }
 346         vhdr = sbi->s_vhdr;
 347
 348         /* Copy parts of the volume header into the superblock */
 349         sb->s_magic = HFSPLUS_VOLHEAD_SIG;
 350         if (be16_to_cpu(vhdr->version) < HFSPLUS_MIN_VERSION ||
 351             be16_to_cpu(vhdr->version) > HFSPLUS_CURRENT_VERSION) {
 352                 printk(KERN_ERR "hfs: wrong filesystem version\n");
 353                 goto cleanup;
 354         }
 355         sbi->total_blocks = be32_to_cpu(vhdr->total_blocks);
 356         sbi->free_blocks = be32_to_cpu(vhdr->free_blocks);
 357         sbi->next_cnid = be32_to_cpu(vhdr->next_cnid);
 358         sbi->file_count = be32_to_cpu(vhdr->file_count);
 359         sbi->folder_count = be32_to_cpu(vhdr->folder_count);
 360         sbi->data_clump_blocks =
 361                 be32_to_cpu(vhdr->data_clump_sz) >> sbi->alloc_blksz_shift;
 362         if (!sbi->data_clump_blocks)
 363                 sbi->data_clump_blocks = 1;
 364         sbi->rsrc_clump_blocks =
 365                 be32_to_cpu(vhdr->rsrc_clump_sz) >> sbi->alloc_blksz_shift;
 366         if (!sbi->rsrc_clump_blocks)
 367                 sbi->rsrc_clump_blocks = 1;
 368
 369         /* Set up operations so we can load metadata */
 370         sb->s_op = &hfsplus_sops;
 371         sb->s_maxbytes = MAX_LFS_FILESIZE;
 372
 373         if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
 374                 printk(KERN_WARNING "hfs: Filesystem was not cleanly unmounted, "
 375                        "running fsck.hfsplus is recommended.  mounting read-only.\n");
 376                 sb->s_flags |= MS_RDONLY;
 377         } else if (sbi->flags & HFSPLUS_SB_FORCE) {
 378                 /* nothing */
 379         } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
 380                 printk(KERN_WARNING "hfs: Filesystem is marked locked, mounting read-only.\n");
 381                 sb->s_flags |= MS_RDONLY;
 382         } else if ((vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) && !(sb->s_flags & MS_RDONLY)) {
 383                 printk(KERN_WARNING "hfs: write access to a journaled filesystem is not supported, "
 384                        "use the force option at your own risk, mounting read-only.\n");
 385                 sb->s_flags |= MS_RDONLY;
 386         }
 387         sbi->flags &= ~HFSPLUS_SB_FORCE;
 388
 389         /* Load metadata objects (B*Trees) */
 390         sbi->ext_tree = hfs_btree_open(sb, HFSPLUS_EXT_CNID);
 391         if (!sbi->ext_tree) {
 392                 printk(KERN_ERR "hfs: failed to load extents file\n");
 393                 goto cleanup;
 394         }
 395         sbi->cat_tree = hfs_btree_open(sb, HFSPLUS_CAT_CNID);
 396         if (!sbi->cat_tree) {
 397                 printk(KERN_ERR "hfs: failed to load catalog file\n");
 398                 goto cleanup;
 399         }
 400
 401         inode = hfsplus_iget(sb, HFSPLUS_ALLOC_CNID);
 402         if (IS_ERR(inode)) {
 403                 printk(KERN_ERR "hfs: failed to load allocation file\n");
 404                 err = PTR_ERR(inode);
 405                 goto cleanup;
 406         }
 407         sbi->alloc_file = inode;
 408
 409         /* Load the root directory */
 410         root = hfsplus_iget(sb, HFSPLUS_ROOT_CNID);
 411         if (IS_ERR(root)) {
 412                 printk(KERN_ERR "hfs: failed to load root directory\n");
 413                 err = PTR_ERR(root);
 414                 goto cleanup;
 415         }
 416         sb->s_root = d_alloc_root(root);
 417         if (!sb->s_root) {
 418                 iput(root);
 419                 err = -ENOMEM;
 420                 goto cleanup;
 421         }
 422         sb->s_root->d_op = &hfsplus_dentry_operations;
 423
 424         str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
 425         str.name = HFSP_HIDDENDIR_NAME;
 426         hfs_find_init(sbi->cat_tree, &fd);
 427         hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_ROOT_CNID, &str);
 428         if (!hfs_brec_read(&fd, &entry, sizeof(entry))) {
 429                 hfs_find_exit(&fd);
 430                 if (entry.type != cpu_to_be16(HFSPLUS_FOLDER))
 431                         goto cleanup;
 432                 inode = hfsplus_iget(sb, be32_to_cpu(entry.folder.id));
 433                 if (IS_ERR(inode)) {
 434                         err = PTR_ERR(inode);
 435                         goto cleanup;
 436                 }
 437                 sbi->hidden_dir = inode;
 438         } else
 439                 hfs_find_exit(&fd);
 440
 441         if (sb->s_flags & MS_RDONLY)
 442                 goto out;
 443
 444         /* H+LX == hfsplusutils, H+Lx == this driver, H+lx is unused
 445          * all three are registered with Apple for our use
 446          */
 447         vhdr->last_mount_vers = cpu_to_be32(HFSP_MOUNT_VERSION);
 448         vhdr->modify_date = hfsp_now2mt();
 449         be32_add_cpu(&vhdr->write_count, 1);
 450         vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_UNMNT);
 451         vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_INCNSTNT);
 452         mark_buffer_dirty(sbi->s_vhbh);
 453         sync_dirty_buffer(sbi->s_vhbh);
 454
 455         if (!sbi->hidden_dir) {
 456                 printk(KERN_DEBUG "hfs: create hidden dir...\n");
 457                 sbi->hidden_dir = hfsplus_new_inode(sb, S_IFDIR);
 458                 hfsplus_create_cat(sbi->hidden_dir->i_ino, sb->s_root->d_inode,
 459                                    &str, sbi->hidden_dir);
 460                 mark_inode_dirty(sbi->hidden_dir);
 461         }
 462 out:
 463         unload_nls(sbi->nls);
 464         sbi->nls = nls;
 465         return 0;
 466
 467 cleanup:
 468         hfsplus_put_super(sb);
 469         unload_nls(nls);
 470         return err;
 471 }
 472
 473 MODULE_AUTHOR("Brad Boyer");
 474 MODULE_DESCRIPTION("Extended Macintosh Filesystem");
 475 MODULE_LICENSE("GPL");
 476
 477 static struct kmem_cache *hfsplus_inode_cachep;
 478
 479 static struct inode *hfsplus_alloc_inode(struct super_block *sb)
 480 {
 481         struct hfsplus_inode_info *i;
 482
 483         i = kmem_cache_alloc(hfsplus_inode_cachep, GFP_KERNEL);
 484         return i ? &i->vfs_inode : NULL;
 485 }
 486
 487 static void hfsplus_destroy_inode(struct inode *inode)
 488 {
 489         kmem_cache_free(hfsplus_inode_cachep, HFSPLUS_I(inode));
 490 }
 491
 492 #define HFSPLUS_INODE_SIZE      sizeof(struct hfsplus_inode_info)
 493
 494 static int hfsplus_get_sb(struct file_system_type *fs_type,
 495                           int flags, const char *dev_name, void *data,
 496                           struct vfsmount *mnt)
 497 {
 498         return get_sb_bdev(fs_type, flags, dev_name, data, hfsplus_fill_super,
 499                            mnt);
 500 }
 501
 502 static struct file_system_type hfsplus_fs_type = {
 503         .owner          = THIS_MODULE,
 504         .name           = "hfsplus",
 505         .get_sb         = hfsplus_get_sb,
 506         .kill_sb        = kill_block_super,
 507         .fs_flags       = FS_REQUIRES_DEV,
 508 };
 509
 510 static void hfsplus_init_once(void *p)
 511 {
 512         struct hfsplus_inode_info *i = p;
 513
 514         inode_init_once(&i->vfs_inode);
 515 }
 516
 517 static int __init init_hfsplus_fs(void)
 518 {
 519         int err;
 520
 521         hfsplus_inode_cachep = kmem_cache_create("hfsplus_icache",
 522                 HFSPLUS_INODE_SIZE, 0, SLAB_HWCACHE_ALIGN,
 523                 hfsplus_init_once);
 524         if (!hfsplus_inode_cachep)
 525                 return -ENOMEM;
 526         err = register_filesystem(&hfsplus_fs_type);
 527         if (err)
 528                 kmem_cache_destroy(hfsplus_inode_cachep);
 529         return err;
 530 }
 531
 532 static void __exit exit_hfsplus_fs(void)
 533 {
 534         unregister_filesystem(&hfsplus_fs_type);
 535         kmem_cache_destroy(hfsplus_inode_cachep);
 536 }
 537
 538 module_init(init_hfsplus_fs)
 539 module_exit(exit_hfsplus_fs)