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   1 /*
   2  *  linux/fs/hfs/inode.c
   3  *
   4  * Copyright (C) 1995-1997  Paul H. Hargrove
   5  * (C) 2003 Ardis Technologies <roman@ardistech.com>
   6  * This file may be distributed under the terms of the GNU General Public License.
   7  *
   8  * This file contains inode-related functions which do not depend on
   9  * which scheme is being used to represent forks.
  10  *
  11  * Based on the minix file system code, (C) 1991, 1992 by Linus Torvalds
  12  */
  13
  14 #include <linux/pagemap.h>
  15 #include <linux/mpage.h>
  16
  17 #include "hfs_fs.h"
  18 #include "btree.h"
  19
  20 static const struct file_operations hfs_file_operations;
  21 static struct inode_operations hfs_file_inode_operations;
  22
  23 /*================ Variable-like macros ================*/
  24
  25 #define HFS_VALID_MODE_BITS  (S_IFREG | S_IFDIR | S_IRWXUGO)
  26
  27 static int hfs_writepage(struct page *page, struct writeback_control *wbc)
  28 {
  29         return block_write_full_page(page, hfs_get_block, wbc);
  30 }
  31
  32 static int hfs_readpage(struct file *file, struct page *page)
  33 {
  34         return block_read_full_page(page, hfs_get_block);
  35 }
  36
  37 static int hfs_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to)
  38 {
  39         return cont_prepare_write(page, from, to, hfs_get_block,
  40                                   &HFS_I(page->mapping->host)->phys_size);
  41 }
  42
  43 static sector_t hfs_bmap(struct address_space *mapping, sector_t block)
  44 {
  45         return generic_block_bmap(mapping, block, hfs_get_block);
  46 }
  47
  48 static int hfs_releasepage(struct page *page, gfp_t mask)
  49 {
  50         struct inode *inode = page->mapping->host;
  51         struct super_block *sb = inode->i_sb;
  52         struct hfs_btree *tree;
  53         struct hfs_bnode *node;
  54         u32 nidx;
  55         int i, res = 1;
  56
  57         switch (inode->i_ino) {
  58         case HFS_EXT_CNID:
  59                 tree = HFS_SB(sb)->ext_tree;
  60                 break;
  61         case HFS_CAT_CNID:
  62                 tree = HFS_SB(sb)->cat_tree;
  63                 break;
  64         default:
  65                 BUG();
  66                 return 0;
  67         }
  68         if (tree->node_size >= PAGE_CACHE_SIZE) {
  69                 nidx = page->index >> (tree->node_size_shift - PAGE_CACHE_SHIFT);
  70                 spin_lock(&tree->hash_lock);
  71                 node = hfs_bnode_findhash(tree, nidx);
  72                 if (!node)
  73                         ;
  74                 else if (atomic_read(&node->refcnt))
  75                         res = 0;
  76                 if (res && node) {
  77                         hfs_bnode_unhash(node);
  78                         hfs_bnode_free(node);
  79                 }
  80                 spin_unlock(&tree->hash_lock);
  81         } else {
  82                 nidx = page->index << (PAGE_CACHE_SHIFT - tree->node_size_shift);
  83                 i = 1 << (PAGE_CACHE_SHIFT - tree->node_size_shift);
  84                 spin_lock(&tree->hash_lock);
  85                 do {
  86                         node = hfs_bnode_findhash(tree, nidx++);
  87                         if (!node)
  88                                 continue;
  89                         if (atomic_read(&node->refcnt)) {
  90                                 res = 0;
  91                                 break;
  92                         }
  93                         hfs_bnode_unhash(node);
  94                         hfs_bnode_free(node);
  95                 } while (--i && nidx < tree->node_count);
  96                 spin_unlock(&tree->hash_lock);
  97         }
  98         return res ? try_to_free_buffers(page) : 0;
  99 }
 100
 101 static ssize_t hfs_direct_IO(int rw, struct kiocb *iocb,
 102                 const struct iovec *iov, loff_t offset, unsigned long nr_segs)
 103 {
 104         struct file *file = iocb->ki_filp;
 105         struct inode *inode = file->f_dentry->d_inode->i_mapping->host;
 106
 107         return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
 108                                   offset, nr_segs, hfs_get_block, NULL);
 109 }
 110
 111 static int hfs_writepages(struct address_space *mapping,
 112                           struct writeback_control *wbc)
 113 {
 114         return mpage_writepages(mapping, wbc, hfs_get_block);
 115 }
 116
 117 struct address_space_operations hfs_btree_aops = {
 118         .readpage       = hfs_readpage,
 119         .writepage      = hfs_writepage,
 120         .sync_page      = block_sync_page,
 121         .prepare_write  = hfs_prepare_write,
 122         .commit_write   = generic_commit_write,
 123         .bmap           = hfs_bmap,
 124         .releasepage    = hfs_releasepage,
 125 };
 126
 127 struct address_space_operations hfs_aops = {
 128         .readpage       = hfs_readpage,
 129         .writepage      = hfs_writepage,
 130         .sync_page      = block_sync_page,
 131         .prepare_write  = hfs_prepare_write,
 132         .commit_write   = generic_commit_write,
 133         .bmap           = hfs_bmap,
 134         .direct_IO      = hfs_direct_IO,
 135         .writepages     = hfs_writepages,
 136 };
 137
 138 /*
 139  * hfs_new_inode
 140  */
 141 struct inode *hfs_new_inode(struct inode *dir, struct qstr *name, int mode)
 142 {
 143         struct super_block *sb = dir->i_sb;
 144         struct inode *inode = new_inode(sb);
 145         if (!inode)
 146                 return NULL;
 147
 148         init_MUTEX(&HFS_I(inode)->extents_lock);
 149         INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
 150         hfs_cat_build_key(sb, (btree_key *)&HFS_I(inode)->cat_key, dir->i_ino, name);
 151         inode->i_ino = HFS_SB(sb)->next_id++;
 152         inode->i_mode = mode;
 153         inode->i_uid = current->fsuid;
 154         inode->i_gid = current->fsgid;
 155         inode->i_nlink = 1;
 156         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
 157         inode->i_blksize = HFS_SB(sb)->alloc_blksz;
 158         HFS_I(inode)->flags = 0;
 159         HFS_I(inode)->rsrc_inode = NULL;
 160         HFS_I(inode)->fs_blocks = 0;
 161         if (S_ISDIR(mode)) {
 162                 inode->i_size = 2;
 163                 HFS_SB(sb)->folder_count++;
 164                 if (dir->i_ino == HFS_ROOT_CNID)
 165                         HFS_SB(sb)->root_dirs++;
 166                 inode->i_op = &hfs_dir_inode_operations;
 167                 inode->i_fop = &hfs_dir_operations;
 168                 inode->i_mode |= S_IRWXUGO;
 169                 inode->i_mode &= ~HFS_SB(inode->i_sb)->s_dir_umask;
 170         } else if (S_ISREG(mode)) {
 171                 HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
 172                 HFS_SB(sb)->file_count++;
 173                 if (dir->i_ino == HFS_ROOT_CNID)
 174                         HFS_SB(sb)->root_files++;
 175                 inode->i_op = &hfs_file_inode_operations;
 176                 inode->i_fop = &hfs_file_operations;
 177                 inode->i_mapping->a_ops = &hfs_aops;
 178                 inode->i_mode |= S_IRUGO|S_IXUGO;
 179                 if (mode & S_IWUSR)
 180                         inode->i_mode |= S_IWUGO;
 181                 inode->i_mode &= ~HFS_SB(inode->i_sb)->s_file_umask;
 182                 HFS_I(inode)->phys_size = 0;
 183                 HFS_I(inode)->alloc_blocks = 0;
 184                 HFS_I(inode)->first_blocks = 0;
 185                 HFS_I(inode)->cached_start = 0;
 186                 HFS_I(inode)->cached_blocks = 0;
 187                 memset(HFS_I(inode)->first_extents, 0, sizeof(hfs_extent_rec));
 188                 memset(HFS_I(inode)->cached_extents, 0, sizeof(hfs_extent_rec));
 189         }
 190         insert_inode_hash(inode);
 191         mark_inode_dirty(inode);
 192         set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
 193         sb->s_dirt = 1;
 194
 195         return inode;
 196 }
 197
 198 void hfs_delete_inode(struct inode *inode)
 199 {
 200         struct super_block *sb = inode->i_sb;
 201
 202         dprint(DBG_INODE, "delete_inode: %lu\n", inode->i_ino);
 203         if (S_ISDIR(inode->i_mode)) {
 204                 HFS_SB(sb)->folder_count--;
 205                 if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
 206                         HFS_SB(sb)->root_dirs--;
 207                 set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
 208                 sb->s_dirt = 1;
 209                 return;
 210         }
 211         HFS_SB(sb)->file_count--;
 212         if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
 213                 HFS_SB(sb)->root_files--;
 214         if (S_ISREG(inode->i_mode)) {
 215                 if (!inode->i_nlink) {
 216                         inode->i_size = 0;
 217                         hfs_file_truncate(inode);
 218                 }
 219         }
 220         set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
 221         sb->s_dirt = 1;
 222 }
 223
 224 void hfs_inode_read_fork(struct inode *inode, struct hfs_extent *ext,
 225                          __be32 __log_size, __be32 phys_size, u32 clump_size)
 226 {
 227         struct super_block *sb = inode->i_sb;
 228         u32 log_size = be32_to_cpu(__log_size);
 229         u16 count;
 230         int i;
 231
 232         memcpy(HFS_I(inode)->first_extents, ext, sizeof(hfs_extent_rec));
 233         for (count = 0, i = 0; i < 3; i++)
 234                 count += be16_to_cpu(ext[i].count);
 235         HFS_I(inode)->first_blocks = count;
 236
 237         inode->i_size = HFS_I(inode)->phys_size = log_size;
 238         HFS_I(inode)->fs_blocks = (log_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
 239         inode_set_bytes(inode, HFS_I(inode)->fs_blocks << sb->s_blocksize_bits);
 240         HFS_I(inode)->alloc_blocks = be32_to_cpu(phys_size) /
 241                                      HFS_SB(sb)->alloc_blksz;
 242         HFS_I(inode)->clump_blocks = clump_size / HFS_SB(sb)->alloc_blksz;
 243         if (!HFS_I(inode)->clump_blocks)
 244                 HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
 245 }
 246
 247 struct hfs_iget_data {
 248         struct hfs_cat_key *key;
 249         hfs_cat_rec *rec;
 250 };
 251
 252 static int hfs_test_inode(struct inode *inode, void *data)
 253 {
 254         struct hfs_iget_data *idata = data;
 255         hfs_cat_rec *rec;
 256
 257         rec = idata->rec;
 258         switch (rec->type) {
 259         case HFS_CDR_DIR:
 260                 return inode->i_ino == be32_to_cpu(rec->dir.DirID);
 261         case HFS_CDR_FIL:
 262                 return inode->i_ino == be32_to_cpu(rec->file.FlNum);
 263         default:
 264                 BUG();
 265                 return 1;
 266         }
 267 }
 268
 269 /*
 270  * hfs_read_inode
 271  */
 272 static int hfs_read_inode(struct inode *inode, void *data)
 273 {
 274         struct hfs_iget_data *idata = data;
 275         struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
 276         hfs_cat_rec *rec;
 277
 278         HFS_I(inode)->flags = 0;
 279         HFS_I(inode)->rsrc_inode = NULL;
 280         init_MUTEX(&HFS_I(inode)->extents_lock);
 281         INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
 282
 283         /* Initialize the inode */
 284         inode->i_uid = hsb->s_uid;
 285         inode->i_gid = hsb->s_gid;
 286         inode->i_nlink = 1;
 287         inode->i_blksize = HFS_SB(inode->i_sb)->alloc_blksz;
 288
 289         if (idata->key)
 290                 HFS_I(inode)->cat_key = *idata->key;
 291         else
 292                 HFS_I(inode)->flags |= HFS_FLG_RSRC;
 293         HFS_I(inode)->tz_secondswest = sys_tz.tz_minuteswest * 60;
 294
 295         rec = idata->rec;
 296         switch (rec->type) {
 297         case HFS_CDR_FIL:
 298                 if (!HFS_IS_RSRC(inode)) {
 299                         hfs_inode_read_fork(inode, rec->file.ExtRec, rec->file.LgLen,
 300                                             rec->file.PyLen, be16_to_cpu(rec->file.ClpSize));
 301                 } else {
 302                         hfs_inode_read_fork(inode, rec->file.RExtRec, rec->file.RLgLen,
 303                                             rec->file.RPyLen, be16_to_cpu(rec->file.ClpSize));
 304                 }
 305
 306                 inode->i_ino = be32_to_cpu(rec->file.FlNum);
 307                 inode->i_mode = S_IRUGO | S_IXUGO;
 308                 if (!(rec->file.Flags & HFS_FIL_LOCK))
 309                         inode->i_mode |= S_IWUGO;
 310                 inode->i_mode &= ~hsb->s_file_umask;
 311                 inode->i_mode |= S_IFREG;
 312                 inode->i_ctime = inode->i_atime = inode->i_mtime =
 313                                 hfs_m_to_utime(rec->file.MdDat);
 314                 inode->i_op = &hfs_file_inode_operations;
 315                 inode->i_fop = &hfs_file_operations;
 316                 inode->i_mapping->a_ops = &hfs_aops;
 317                 break;
 318         case HFS_CDR_DIR:
 319                 inode->i_ino = be32_to_cpu(rec->dir.DirID);
 320                 inode->i_size = be16_to_cpu(rec->dir.Val) + 2;
 321                 HFS_I(inode)->fs_blocks = 0;
 322                 inode->i_mode = S_IFDIR | (S_IRWXUGO & ~hsb->s_dir_umask);
 323                 inode->i_ctime = inode->i_atime = inode->i_mtime =
 324                                 hfs_m_to_utime(rec->dir.MdDat);
 325                 inode->i_op = &hfs_dir_inode_operations;
 326                 inode->i_fop = &hfs_dir_operations;
 327                 break;
 328         default:
 329                 make_bad_inode(inode);
 330         }
 331         return 0;
 332 }
 333
 334 /*
 335  * __hfs_iget()
 336  *
 337  * Given the MDB for a HFS filesystem, a 'key' and an 'entry' in
 338  * the catalog B-tree and the 'type' of the desired file return the
 339  * inode for that file/directory or NULL.  Note that 'type' indicates
 340  * whether we want the actual file or directory, or the corresponding
 341  * metadata (AppleDouble header file or CAP metadata file).
 342  */
 343 struct inode *hfs_iget(struct super_block *sb, struct hfs_cat_key *key, hfs_cat_rec *rec)
 344 {
 345         struct hfs_iget_data data = { key, rec };
 346         struct inode *inode;
 347         u32 cnid;
 348
 349         switch (rec->type) {
 350         case HFS_CDR_DIR:
 351                 cnid = be32_to_cpu(rec->dir.DirID);
 352                 break;
 353         case HFS_CDR_FIL:
 354                 cnid = be32_to_cpu(rec->file.FlNum);
 355                 break;
 356         default:
 357                 return NULL;
 358         }
 359         inode = iget5_locked(sb, cnid, hfs_test_inode, hfs_read_inode, &data);
 360         if (inode && (inode->i_state & I_NEW))
 361                 unlock_new_inode(inode);
 362         return inode;
 363 }
 364
 365 void hfs_inode_write_fork(struct inode *inode, struct hfs_extent *ext,
 366                           __be32 *log_size, __be32 *phys_size)
 367 {
 368         memcpy(ext, HFS_I(inode)->first_extents, sizeof(hfs_extent_rec));
 369
 370         if (log_size)
 371                 *log_size = cpu_to_be32(inode->i_size);
 372         if (phys_size)
 373                 *phys_size = cpu_to_be32(HFS_I(inode)->alloc_blocks *
 374                                          HFS_SB(inode->i_sb)->alloc_blksz);
 375 }
 376
 377 int hfs_write_inode(struct inode *inode, int unused)
 378 {
 379         struct inode *main_inode = inode;
 380         struct hfs_find_data fd;
 381         hfs_cat_rec rec;
 382
 383         dprint(DBG_INODE, "hfs_write_inode: %lu\n", inode->i_ino);
 384         hfs_ext_write_extent(inode);
 385
 386         if (inode->i_ino < HFS_FIRSTUSER_CNID) {
 387                 switch (inode->i_ino) {
 388                 case HFS_ROOT_CNID:
 389                         break;
 390                 case HFS_EXT_CNID:
 391                         hfs_btree_write(HFS_SB(inode->i_sb)->ext_tree);
 392                         return 0;
 393                 case HFS_CAT_CNID:
 394                         hfs_btree_write(HFS_SB(inode->i_sb)->cat_tree);
 395                         return 0;
 396                 default:
 397                         BUG();
 398                         return -EIO;
 399                 }
 400         }
 401
 402         if (HFS_IS_RSRC(inode))
 403                 main_inode = HFS_I(inode)->rsrc_inode;
 404
 405         if (!main_inode->i_nlink)
 406                 return 0;
 407
 408         if (hfs_find_init(HFS_SB(main_inode->i_sb)->cat_tree, &fd))
 409                 /* panic? */
 410                 return -EIO;
 411
 412         fd.search_key->cat = HFS_I(main_inode)->cat_key;
 413         if (hfs_brec_find(&fd))
 414                 /* panic? */
 415                 goto out;
 416
 417         if (S_ISDIR(main_inode->i_mode)) {
 418                 if (fd.entrylength < sizeof(struct hfs_cat_dir))
 419                         /* panic? */;
 420                 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
 421                            sizeof(struct hfs_cat_dir));
 422                 if (rec.type != HFS_CDR_DIR ||
 423                     be32_to_cpu(rec.dir.DirID) != inode->i_ino) {
 424                 }
 425
 426                 rec.dir.MdDat = hfs_u_to_mtime(inode->i_mtime);
 427                 rec.dir.Val = cpu_to_be16(inode->i_size - 2);
 428
 429                 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
 430                             sizeof(struct hfs_cat_dir));
 431         } else if (HFS_IS_RSRC(inode)) {
 432                 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
 433                                sizeof(struct hfs_cat_file));
 434                 hfs_inode_write_fork(inode, rec.file.RExtRec,
 435                                      &rec.file.RLgLen, &rec.file.RPyLen);
 436                 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
 437                                 sizeof(struct hfs_cat_file));
 438         } else {
 439                 if (fd.entrylength < sizeof(struct hfs_cat_file))
 440                         /* panic? */;
 441                 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
 442                            sizeof(struct hfs_cat_file));
 443                 if (rec.type != HFS_CDR_FIL ||
 444                     be32_to_cpu(rec.file.FlNum) != inode->i_ino) {
 445                 }
 446
 447                 if (inode->i_mode & S_IWUSR)
 448                         rec.file.Flags &= ~HFS_FIL_LOCK;
 449                 else
 450                         rec.file.Flags |= HFS_FIL_LOCK;
 451                 hfs_inode_write_fork(inode, rec.file.ExtRec, &rec.file.LgLen, &rec.file.PyLen);
 452                 rec.file.MdDat = hfs_u_to_mtime(inode->i_mtime);
 453
 454                 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
 455                             sizeof(struct hfs_cat_file));
 456         }
 457 out:
 458         hfs_find_exit(&fd);
 459         return 0;
 460 }
 461
 462 static struct dentry *hfs_file_lookup(struct inode *dir, struct dentry *dentry,
 463                                       struct nameidata *nd)
 464 {
 465         struct inode *inode = NULL;
 466         hfs_cat_rec rec;
 467         struct hfs_find_data fd;
 468         int res;
 469
 470         if (HFS_IS_RSRC(dir) || strcmp(dentry->d_name.name, "rsrc"))
 471                 goto out;
 472
 473         inode = HFS_I(dir)->rsrc_inode;
 474         if (inode)
 475                 goto out;
 476
 477         inode = new_inode(dir->i_sb);
 478         if (!inode)
 479                 return ERR_PTR(-ENOMEM);
 480
 481         hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
 482         fd.search_key->cat = HFS_I(dir)->cat_key;
 483         res = hfs_brec_read(&fd, &rec, sizeof(rec));
 484         if (!res) {
 485                 struct hfs_iget_data idata = { NULL, &rec };
 486                 hfs_read_inode(inode, &idata);
 487         }
 488         hfs_find_exit(&fd);
 489         if (res) {
 490                 iput(inode);
 491                 return ERR_PTR(res);
 492         }
 493         HFS_I(inode)->rsrc_inode = dir;
 494         HFS_I(dir)->rsrc_inode = inode;
 495         igrab(dir);
 496         hlist_add_head(&inode->i_hash, &HFS_SB(dir->i_sb)->rsrc_inodes);
 497         mark_inode_dirty(inode);
 498 out:
 499         d_add(dentry, inode);
 500         return NULL;
 501 }
 502
 503 void hfs_clear_inode(struct inode *inode)
 504 {
 505         if (HFS_IS_RSRC(inode) && HFS_I(inode)->rsrc_inode) {
 506                 HFS_I(HFS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
 507                 iput(HFS_I(inode)->rsrc_inode);
 508         }
 509 }
 510
 511 static int hfs_permission(struct inode *inode, int mask,
 512                           struct nameidata *nd)
 513 {
 514         if (S_ISREG(inode->i_mode) && mask & MAY_EXEC)
 515                 return 0;
 516         return generic_permission(inode, mask, NULL);
 517 }
 518
 519 static int hfs_file_open(struct inode *inode, struct file *file)
 520 {
 521         if (HFS_IS_RSRC(inode))
 522                 inode = HFS_I(inode)->rsrc_inode;
 523         if (atomic_read(&file->f_count) != 1)
 524                 return 0;
 525         atomic_inc(&HFS_I(inode)->opencnt);
 526         return 0;
 527 }
 528
 529 static int hfs_file_release(struct inode *inode, struct file *file)
 530 {
 531         //struct super_block *sb = inode->i_sb;
 532
 533         if (HFS_IS_RSRC(inode))
 534                 inode = HFS_I(inode)->rsrc_inode;
 535         if (atomic_read(&file->f_count) != 0)
 536                 return 0;
 537         if (atomic_dec_and_test(&HFS_I(inode)->opencnt)) {
 538                 mutex_lock(&inode->i_mutex);
 539                 hfs_file_truncate(inode);
 540                 //if (inode->i_flags & S_DEAD) {
 541                 //      hfs_delete_cat(inode->i_ino, HFSPLUS_SB(sb).hidden_dir, NULL);
 542                 //      hfs_delete_inode(inode);
 543                 //}
 544                 mutex_unlock(&inode->i_mutex);
 545         }
 546         return 0;
 547 }
 548
 549 /*
 550  * hfs_notify_change()
 551  *
 552  * Based very closely on fs/msdos/inode.c by Werner Almesberger
 553  *
 554  * This is the notify_change() field in the super_operations structure
 555  * for HFS file systems.  The purpose is to take that changes made to
 556  * an inode and apply then in a filesystem-dependent manner.  In this
 557  * case the process has a few of tasks to do:
 558  *  1) prevent changes to the i_uid and i_gid fields.
 559  *  2) map file permissions to the closest allowable permissions
 560  *  3) Since multiple Linux files can share the same on-disk inode under
 561  *     HFS (for instance the data and resource forks of a file) a change
 562  *     to permissions must be applied to all other in-core inodes which
 563  *     correspond to the same HFS file.
 564  */
 565
 566 int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
 567 {
 568         struct inode *inode = dentry->d_inode;
 569         struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
 570         int error;
 571
 572         error = inode_change_ok(inode, attr); /* basic permission checks */
 573         if (error)
 574                 return error;
 575
 576         /* no uig/gid changes and limit which mode bits can be set */
 577         if (((attr->ia_valid & ATTR_UID) &&
 578              (attr->ia_uid != hsb->s_uid)) ||
 579             ((attr->ia_valid & ATTR_GID) &&
 580              (attr->ia_gid != hsb->s_gid)) ||
 581             ((attr->ia_valid & ATTR_MODE) &&
 582              ((S_ISDIR(inode->i_mode) &&
 583                (attr->ia_mode != inode->i_mode)) ||
 584               (attr->ia_mode & ~HFS_VALID_MODE_BITS)))) {
 585                 return hsb->s_quiet ? 0 : error;
 586         }
 587
 588         if (attr->ia_valid & ATTR_MODE) {
 589                 /* Only the 'w' bits can ever change and only all together. */
 590                 if (attr->ia_mode & S_IWUSR)
 591                         attr->ia_mode = inode->i_mode | S_IWUGO;
 592                 else
 593                         attr->ia_mode = inode->i_mode & ~S_IWUGO;
 594                 attr->ia_mode &= S_ISDIR(inode->i_mode) ? ~hsb->s_dir_umask: ~hsb->s_file_umask;
 595         }
 596         error = inode_setattr(inode, attr);
 597         if (error)
 598                 return error;
 599
 600         return 0;
 601 }
 602
 603
 604 static const struct file_operations hfs_file_operations = {
 605         .llseek         = generic_file_llseek,
 606         .read           = generic_file_read,
 607         .write          = generic_file_write,
 608         .mmap           = generic_file_mmap,
 609         .sendfile       = generic_file_sendfile,
 610         .fsync          = file_fsync,
 611         .open           = hfs_file_open,
 612         .release        = hfs_file_release,
 613 };
 614
 615 static struct inode_operations hfs_file_inode_operations = {
 616         .lookup         = hfs_file_lookup,
 617         .truncate       = hfs_file_truncate,
 618         .setattr        = hfs_inode_setattr,
 619         .permission     = hfs_permission,
 620         .setxattr       = hfs_setxattr,
 621         .getxattr       = hfs_getxattr,
 622         .listxattr      = hfs_listxattr,
 623 };