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                 set_bit(HFSPLUS_SB_WRITEBACKUP, &sbi->flags);
 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         int write_backup = 0;
 161         int error, error2;
 162
 163         dprint(DBG_SUPER, "hfsplus_write_super\n");
 164
 165         sb->s_dirt = 0;
 166
 167         mutex_lock(&sbi->vh_mutex);
 168         mutex_lock(&sbi->alloc_mutex);
 169         vhdr->free_blocks = cpu_to_be32(sbi->free_blocks);
 170         vhdr->next_cnid = cpu_to_be32(sbi->next_cnid);
 171         vhdr->folder_count = cpu_to_be32(sbi->folder_count);
 172         vhdr->file_count = cpu_to_be32(sbi->file_count);
 173
 174         if (test_and_clear_bit(HFSPLUS_SB_WRITEBACKUP, &sbi->flags)) {
 175                 memcpy(sbi->s_backup_vhdr, sbi->s_vhdr, sizeof(*sbi->s_vhdr));
 176                 write_backup = 1;
 177         }
 178
 179         error = hfsplus_submit_bio(sb->s_bdev,
 180                                    sbi->part_start + HFSPLUS_VOLHEAD_SECTOR,
 181                                    sbi->s_vhdr, WRITE_SYNC);
 182         if (!write_backup)
 183                 goto out;
 184
 185         error2 = hfsplus_submit_bio(sb->s_bdev,
 186                                   sbi->part_start + sbi->sect_count - 2,
 187                                   sbi->s_backup_vhdr, WRITE_SYNC);
 188         if (!error)
 189                 error2 = error;
 190 out:
 191         mutex_unlock(&sbi->alloc_mutex);
 192         mutex_unlock(&sbi->vh_mutex);
 193         return error;
 194 }
 195
 196 static void hfsplus_write_super(struct super_block *sb)
 197 {
 198         if (!(sb->s_flags & MS_RDONLY))
 199                 hfsplus_sync_fs(sb, 1);
 200         else
 201                 sb->s_dirt = 0;
 202 }
 203
 204 static void hfsplus_put_super(struct super_block *sb)
 205 {
 206         struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 207
 208         dprint(DBG_SUPER, "hfsplus_put_super\n");
 209
 210         if (!sb->s_fs_info)
 211                 return;
 212
 213         if (!(sb->s_flags & MS_RDONLY) && sbi->s_vhdr) {
 214                 struct hfsplus_vh *vhdr = sbi->s_vhdr;
 215
 216                 vhdr->modify_date = hfsp_now2mt();
 217                 vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_UNMNT);
 218                 vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_INCNSTNT);
 219
 220                 hfsplus_sync_fs(sb, 1);
 221         }
 222
 223         hfs_btree_close(sbi->cat_tree);
 224         hfs_btree_close(sbi->ext_tree);
 225         iput(sbi->alloc_file);
 226         iput(sbi->hidden_dir);
 227         kfree(sbi->s_vhdr);
 228         kfree(sbi->s_backup_vhdr);
 229         unload_nls(sbi->nls);
 230         kfree(sb->s_fs_info);
 231         sb->s_fs_info = NULL;
 232 }
 233
 234 static int hfsplus_statfs(struct dentry *dentry, struct kstatfs *buf)
 235 {
 236         struct super_block *sb = dentry->d_sb;
 237         struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
 238         u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 239
 240         buf->f_type = HFSPLUS_SUPER_MAGIC;
 241         buf->f_bsize = sb->s_blocksize;
 242         buf->f_blocks = sbi->total_blocks << sbi->fs_shift;
 243         buf->f_bfree = sbi->free_blocks << sbi->fs_shift;
 244         buf->f_bavail = buf->f_bfree;
 245         buf->f_files = 0xFFFFFFFF;
 246         buf->f_ffree = 0xFFFFFFFF - sbi->next_cnid;
 247         buf->f_fsid.val[0] = (u32)id;
 248         buf->f_fsid.val[1] = (u32)(id >> 32);
 249         buf->f_namelen = HFSPLUS_MAX_STRLEN;
 250
 251         return 0;
 252 }
 253
 254 static int hfsplus_remount(struct super_block *sb, int *flags, char *data)
 255 {
 256         if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
 257                 return 0;
 258         if (!(*flags & MS_RDONLY)) {
 259                 struct hfsplus_vh *vhdr = HFSPLUS_SB(sb)->s_vhdr;
 260                 int force = 0;
 261
 262                 if (!hfsplus_parse_options_remount(data, &force))
 263                         return -EINVAL;
 264
 265                 if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
 266                         printk(KERN_WARNING "hfs: filesystem was not cleanly unmounted, "
 267                                "running fsck.hfsplus is recommended.  leaving read-only.\n");
 268                         sb->s_flags |= MS_RDONLY;
 269                         *flags |= MS_RDONLY;
 270                 } else if (force) {
 271                         /* nothing */
 272                 } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
 273                         printk(KERN_WARNING "hfs: filesystem is marked locked, leaving read-only.\n");
 274                         sb->s_flags |= MS_RDONLY;
 275                         *flags |= MS_RDONLY;
 276                 } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) {
 277                         printk(KERN_WARNING "hfs: filesystem is marked journaled, leaving read-only.\n");
 278                         sb->s_flags |= MS_RDONLY;
 279                         *flags |= MS_RDONLY;
 280                 }
 281         }
 282         return 0;
 283 }
 284
 285 static const struct super_operations hfsplus_sops = {
 286         .alloc_inode    = hfsplus_alloc_inode,
 287         .destroy_inode  = hfsplus_destroy_inode,
 288         .write_inode    = hfsplus_write_inode,
 289         .evict_inode    = hfsplus_evict_inode,
 290         .put_super      = hfsplus_put_super,
 291         .write_super    = hfsplus_write_super,
 292         .sync_fs        = hfsplus_sync_fs,
 293         .statfs         = hfsplus_statfs,
 294         .remount_fs     = hfsplus_remount,
 295         .show_options   = hfsplus_show_options,
 296 };
 297
 298 static int hfsplus_fill_super(struct super_block *sb, void *data, int silent)
 299 {
 300         struct hfsplus_vh *vhdr;
 301         struct hfsplus_sb_info *sbi;
 302         hfsplus_cat_entry entry;
 303         struct hfs_find_data fd;
 304         struct inode *root, *inode;
 305         struct qstr str;
 306         struct nls_table *nls = NULL;
 307         int err = -EINVAL;
 308
 309         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
 310         if (!sbi)
 311                 return -ENOMEM;
 312
 313         sb->s_fs_info = sbi;
 314         mutex_init(&sbi->alloc_mutex);
 315         mutex_init(&sbi->vh_mutex);
 316         hfsplus_fill_defaults(sbi);
 317         if (!hfsplus_parse_options(data, sbi)) {
 318                 printk(KERN_ERR "hfs: unable to parse mount options\n");
 319                 err = -EINVAL;
 320                 goto cleanup;
 321         }
 322
 323         /* temporarily use utf8 to correctly find the hidden dir below */
 324         nls = sbi->nls;
 325         sbi->nls = load_nls("utf8");
 326         if (!sbi->nls) {
 327                 printk(KERN_ERR "hfs: unable to load nls for utf8\n");
 328                 err = -EINVAL;
 329                 goto cleanup;
 330         }
 331
 332         /* Grab the volume header */
 333         if (hfsplus_read_wrapper(sb)) {
 334                 if (!silent)
 335                         printk(KERN_WARNING "hfs: unable to find HFS+ superblock\n");
 336                 err = -EINVAL;
 337                 goto cleanup;
 338         }
 339         vhdr = sbi->s_vhdr;
 340
 341         /* Copy parts of the volume header into the superblock */
 342         sb->s_magic = HFSPLUS_VOLHEAD_SIG;
 343         if (be16_to_cpu(vhdr->version) < HFSPLUS_MIN_VERSION ||
 344             be16_to_cpu(vhdr->version) > HFSPLUS_CURRENT_VERSION) {
 345                 printk(KERN_ERR "hfs: wrong filesystem version\n");
 346                 goto cleanup;
 347         }
 348         sbi->total_blocks = be32_to_cpu(vhdr->total_blocks);
 349         sbi->free_blocks = be32_to_cpu(vhdr->free_blocks);
 350         sbi->next_cnid = be32_to_cpu(vhdr->next_cnid);
 351         sbi->file_count = be32_to_cpu(vhdr->file_count);
 352         sbi->folder_count = be32_to_cpu(vhdr->folder_count);
 353         sbi->data_clump_blocks =
 354                 be32_to_cpu(vhdr->data_clump_sz) >> sbi->alloc_blksz_shift;
 355         if (!sbi->data_clump_blocks)
 356                 sbi->data_clump_blocks = 1;
 357         sbi->rsrc_clump_blocks =
 358                 be32_to_cpu(vhdr->rsrc_clump_sz) >> sbi->alloc_blksz_shift;
 359         if (!sbi->rsrc_clump_blocks)
 360                 sbi->rsrc_clump_blocks = 1;
 361
 362         /* Set up operations so we can load metadata */
 363         sb->s_op = &hfsplus_sops;
 364         sb->s_maxbytes = MAX_LFS_FILESIZE;
 365
 366         if (!(vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_UNMNT))) {
 367                 printk(KERN_WARNING "hfs: Filesystem was not cleanly unmounted, "
 368                        "running fsck.hfsplus is recommended.  mounting read-only.\n");
 369                 sb->s_flags |= MS_RDONLY;
 370         } else if (test_and_clear_bit(HFSPLUS_SB_FORCE, &sbi->flags)) {
 371                 /* nothing */
 372         } else if (vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_SOFTLOCK)) {
 373                 printk(KERN_WARNING "hfs: Filesystem is marked locked, mounting read-only.\n");
 374                 sb->s_flags |= MS_RDONLY;
 375         } else if ((vhdr->attributes & cpu_to_be32(HFSPLUS_VOL_JOURNALED)) && !(sb->s_flags & MS_RDONLY)) {
 376                 printk(KERN_WARNING "hfs: write access to a journaled filesystem is not supported, "
 377                        "use the force option at your own risk, mounting read-only.\n");
 378                 sb->s_flags |= MS_RDONLY;
 379         }
 380
 381         /* Load metadata objects (B*Trees) */
 382         sbi->ext_tree = hfs_btree_open(sb, HFSPLUS_EXT_CNID);
 383         if (!sbi->ext_tree) {
 384                 printk(KERN_ERR "hfs: failed to load extents file\n");
 385                 goto cleanup;
 386         }
 387         sbi->cat_tree = hfs_btree_open(sb, HFSPLUS_CAT_CNID);
 388         if (!sbi->cat_tree) {
 389                 printk(KERN_ERR "hfs: failed to load catalog file\n");
 390                 goto cleanup;
 391         }
 392
 393         inode = hfsplus_iget(sb, HFSPLUS_ALLOC_CNID);
 394         if (IS_ERR(inode)) {
 395                 printk(KERN_ERR "hfs: failed to load allocation file\n");
 396                 err = PTR_ERR(inode);
 397                 goto cleanup;
 398         }
 399         sbi->alloc_file = inode;
 400
 401         /* Load the root directory */
 402         root = hfsplus_iget(sb, HFSPLUS_ROOT_CNID);
 403         if (IS_ERR(root)) {
 404                 printk(KERN_ERR "hfs: failed to load root directory\n");
 405                 err = PTR_ERR(root);
 406                 goto cleanup;
 407         }
 408         sb->s_root = d_alloc_root(root);
 409         if (!sb->s_root) {
 410                 iput(root);
 411                 err = -ENOMEM;
 412                 goto cleanup;
 413         }
 414         sb->s_root->d_op = &hfsplus_dentry_operations;
 415
 416         str.len = sizeof(HFSP_HIDDENDIR_NAME) - 1;
 417         str.name = HFSP_HIDDENDIR_NAME;
 418         hfs_find_init(sbi->cat_tree, &fd);
 419         hfsplus_cat_build_key(sb, fd.search_key, HFSPLUS_ROOT_CNID, &str);
 420         if (!hfs_brec_read(&fd, &entry, sizeof(entry))) {
 421                 hfs_find_exit(&fd);
 422                 if (entry.type != cpu_to_be16(HFSPLUS_FOLDER))
 423                         goto cleanup;
 424                 inode = hfsplus_iget(sb, be32_to_cpu(entry.folder.id));
 425                 if (IS_ERR(inode)) {
 426                         err = PTR_ERR(inode);
 427                         goto cleanup;
 428                 }
 429                 sbi->hidden_dir = inode;
 430         } else
 431                 hfs_find_exit(&fd);
 432
 433         if (sb->s_flags & MS_RDONLY)
 434                 goto out;
 435
 436         /* H+LX == hfsplusutils, H+Lx == this driver, H+lx is unused
 437          * all three are registered with Apple for our use
 438          */
 439         vhdr->last_mount_vers = cpu_to_be32(HFSP_MOUNT_VERSION);
 440         vhdr->modify_date = hfsp_now2mt();
 441         be32_add_cpu(&vhdr->write_count, 1);
 442         vhdr->attributes &= cpu_to_be32(~HFSPLUS_VOL_UNMNT);
 443         vhdr->attributes |= cpu_to_be32(HFSPLUS_VOL_INCNSTNT);
 444         hfsplus_sync_fs(sb, 1);
 445
 446         if (!sbi->hidden_dir) {
 447                 mutex_lock(&sbi->vh_mutex);
 448                 sbi->hidden_dir = hfsplus_new_inode(sb, S_IFDIR);
 449                 hfsplus_create_cat(sbi->hidden_dir->i_ino, sb->s_root->d_inode,
 450                                    &str, sbi->hidden_dir);
 451                 mutex_unlock(&sbi->vh_mutex);
 452
 453                 mark_inode_dirty(sbi->hidden_dir);
 454         }
 455 out:
 456         unload_nls(sbi->nls);
 457         sbi->nls = nls;
 458         return 0;
 459
 460 cleanup:
 461         hfsplus_put_super(sb);
 462         unload_nls(nls);
 463         return err;
 464 }
 465
 466 MODULE_AUTHOR("Brad Boyer");
 467 MODULE_DESCRIPTION("Extended Macintosh Filesystem");
 468 MODULE_LICENSE("GPL");
 469
 470 static struct kmem_cache *hfsplus_inode_cachep;
 471
 472 static struct inode *hfsplus_alloc_inode(struct super_block *sb)
 473 {
 474         struct hfsplus_inode_info *i;
 475
 476         i = kmem_cache_alloc(hfsplus_inode_cachep, GFP_KERNEL);
 477         return i ? &i->vfs_inode : NULL;
 478 }
 479
 480 static void hfsplus_destroy_inode(struct inode *inode)
 481 {
 482         kmem_cache_free(hfsplus_inode_cachep, HFSPLUS_I(inode));
 483 }
 484
 485 #define HFSPLUS_INODE_SIZE      sizeof(struct hfsplus_inode_info)
 486
 487 static struct dentry *hfsplus_mount(struct file_system_type *fs_type,
 488                           int flags, const char *dev_name, void *data)
 489 {
 490         return mount_bdev(fs_type, flags, dev_name, data, hfsplus_fill_super);
 491 }
 492
 493 static struct file_system_type hfsplus_fs_type = {
 494         .owner          = THIS_MODULE,
 495         .name           = "hfsplus",
 496         .mount          = hfsplus_mount,
 497         .kill_sb        = kill_block_super,
 498         .fs_flags       = FS_REQUIRES_DEV,
 499 };
 500
 501 static void hfsplus_init_once(void *p)
 502 {
 503         struct hfsplus_inode_info *i = p;
 504
 505         inode_init_once(&i->vfs_inode);
 506 }
 507
 508 static int __init init_hfsplus_fs(void)
 509 {
 510         int err;
 511
 512         hfsplus_inode_cachep = kmem_cache_create("hfsplus_icache",
 513                 HFSPLUS_INODE_SIZE, 0, SLAB_HWCACHE_ALIGN,
 514                 hfsplus_init_once);
 515         if (!hfsplus_inode_cachep)
 516                 return -ENOMEM;
 517         err = register_filesystem(&hfsplus_fs_type);
 518         if (err)
 519                 kmem_cache_destroy(hfsplus_inode_cachep);
 520         return err;
 521 }
 522
 523 static void __exit exit_hfsplus_fs(void)
 524 {
 525         unregister_filesystem(&hfsplus_fs_type);
 526         kmem_cache_destroy(hfsplus_inode_cachep);
 527 }
 528
 529 module_init(init_hfsplus_fs)
 530 module_exit(exit_hfsplus_fs)