fs/hfs/inode.c

   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/version.h>
  16 #include <linux/mpage.h>
  17
  18 #include "hfs_fs.h"
  19 #include "btree.h"
  20
  21 /*================ Variable-like macros ================*/
  22
  23 #define HFS_VALID_MODE_BITS  (S_IFREG | S_IFDIR | S_IRWXUGO)
  24
  25 static int hfs_writepage(struct page *page, struct writeback_control *wbc)
  26 {
  27         return block_write_full_page(page, hfs_get_block, wbc);
  28 }
  29
  30 static int hfs_readpage(struct file *file, struct page *page)
  31 {
  32         return block_read_full_page(page, hfs_get_block);
  33 }
  34
  35 static int hfs_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to)
  36 {
  37         return cont_prepare_write(page, from, to, hfs_get_block,
  38                                   &HFS_I(page->mapping->host)->phys_size);
  39 }
  40
  41 static sector_t hfs_bmap(struct address_space *mapping, sector_t block)
  42 {
  43         return generic_block_bmap(mapping, block, hfs_get_block);
  44 }
  45
  46 int hfs_releasepage(struct page *page, int mask)
  47 {
  48         struct inode *inode = page->mapping->host;
  49         struct super_block *sb = inode->i_sb;
  50         struct hfs_btree *tree;
  51         struct hfs_bnode *node;
  52         u32 nidx;
  53         int i, res = 1;
  54
  55         switch (inode->i_ino) {
  56         case HFS_EXT_CNID:
  57                 tree = HFS_SB(sb)->ext_tree;
  58                 break;
  59         case HFS_CAT_CNID:
  60                 tree = HFS_SB(sb)->cat_tree;
  61                 break;
  62         default:
  63                 BUG();
  64                 return 0;
  65         }
  66         if (tree->node_size >= PAGE_CACHE_SIZE) {
  67                 nidx = page->index >> (tree->node_size_shift - PAGE_CACHE_SHIFT);
  68                 spin_lock(&tree->hash_lock);
  69                 node = hfs_bnode_findhash(tree, nidx);
  70                 if (!node)
  71                         ;
  72                 else if (atomic_read(&node->refcnt))
  73                         res = 0;
  74                 else for (i = 0; i < tree->pages_per_bnode; i++) {
  75                         if (PageActive(node->page[i])) {
  76                                 res = 0;
  77                                 break;
  78                         }
  79                 }
  80                 if (res && node) {
  81                         hfs_bnode_unhash(node);
  82                         hfs_bnode_free(node);
  83                 }
  84                 spin_unlock(&tree->hash_lock);
  85         } else {
  86                 nidx = page->index << (PAGE_CACHE_SHIFT - tree->node_size_shift);
  87                 i = 1 << (PAGE_CACHE_SHIFT - tree->node_size_shift);
  88                 spin_lock(&tree->hash_lock);
  89                 do {
  90                         node = hfs_bnode_findhash(tree, nidx++);
  91                         if (!node)
  92                                 continue;
  93                         if (atomic_read(&node->refcnt)) {
  94                                 res = 0;
  95                                 break;
  96                         }
  97                         hfs_bnode_unhash(node);
  98                         hfs_bnode_free(node);
  99                 } while (--i && nidx < tree->node_count);
 100                 spin_unlock(&tree->hash_lock);
 101         }
 102         //printk("releasepage: %lu,%x = %d\n", page->index, mask, res);
 103         return res;
 104 }
 105
 106 static int hfs_get_blocks(struct inode *inode, sector_t iblock, unsigned long max_blocks,
 107                           struct buffer_head *bh_result, int create)
 108 {
 109         int ret;
 110
 111         ret = hfs_get_block(inode, iblock, bh_result, create);
 112         if (!ret)
 113                 bh_result->b_size = (1 << inode->i_blkbits);
 114         return ret;
 115 }
 116
 117 static ssize_t hfs_direct_IO(int rw, struct kiocb *iocb,
 118                 const struct iovec *iov, loff_t offset, unsigned long nr_segs)
 119 {
 120         struct file *file = iocb->ki_filp;
 121         struct inode *inode = file->f_dentry->d_inode->i_mapping->host;
 122
 123         return blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
 124                                   offset, nr_segs, hfs_get_blocks, NULL);
 125 }
 126
 127 static int hfs_writepages(struct address_space *mapping,
 128                           struct writeback_control *wbc)
 129 {
 130         return mpage_writepages(mapping, wbc, hfs_get_block);
 131 }
 132
 133 struct address_space_operations hfs_btree_aops = {
 134         .readpage       = hfs_readpage,
 135         .writepage      = hfs_writepage,
 136         .sync_page      = block_sync_page,
 137         .prepare_write  = hfs_prepare_write,
 138         .commit_write   = generic_commit_write,
 139         .bmap           = hfs_bmap,
 140         .releasepage    = hfs_releasepage,
 141 };
 142
 143 struct address_space_operations hfs_aops = {
 144         .readpage       = hfs_readpage,
 145         .writepage      = hfs_writepage,
 146         .sync_page      = block_sync_page,
 147         .prepare_write  = hfs_prepare_write,
 148         .commit_write   = generic_commit_write,
 149         .bmap           = hfs_bmap,
 150         .direct_IO      = hfs_direct_IO,
 151         .writepages     = hfs_writepages,
 152 };
 153
 154 /*
 155  * hfs_new_inode
 156  */
 157 struct inode *hfs_new_inode(struct inode *dir, struct qstr *name, int mode)
 158 {
 159         struct super_block *sb = dir->i_sb;
 160         struct inode *inode = new_inode(sb);
 161         if (!inode)
 162                 return NULL;
 163
 164         init_MUTEX(&HFS_I(inode)->extents_lock);
 165         INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
 166         hfs_cat_build_key((btree_key *)&HFS_I(inode)->cat_key, dir->i_ino, name);
 167         inode->i_ino = HFS_SB(sb)->next_id++;
 168         inode->i_mode = mode;
 169         inode->i_uid = current->fsuid;
 170         inode->i_gid = current->fsgid;
 171         inode->i_nlink = 1;
 172         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 173         HFS_I(inode)->flags = 0;
 174         HFS_I(inode)->rsrc_inode = NULL;
 175         if (S_ISDIR(inode->i_mode)) {
 176                 inode->i_size = 2;
 177                 HFS_SB(sb)->folder_count++;
 178                 if (dir->i_ino == HFS_ROOT_CNID)
 179                         HFS_SB(sb)->root_dirs++;
 180                 inode->i_op = &hfs_dir_inode_operations;
 181                 inode->i_fop = &hfs_dir_operations;
 182         } else if (S_ISREG(inode->i_mode)) {
 183                 HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
 184                 HFS_SB(sb)->file_count++;
 185                 if (dir->i_ino == HFS_ROOT_CNID)
 186                         HFS_SB(sb)->root_files++;
 187                 inode->i_op = &hfs_file_inode_operations;
 188                 inode->i_fop = &hfs_file_operations;
 189                 inode->i_mapping->a_ops = &hfs_aops;
 190                 HFS_I(inode)->phys_size = 0;
 191                 HFS_I(inode)->alloc_blocks = 0;
 192                 HFS_I(inode)->first_blocks = 0;
 193                 HFS_I(inode)->cached_start = 0;
 194                 HFS_I(inode)->cached_blocks = 0;
 195                 memset(HFS_I(inode)->first_extents, 0, sizeof(hfs_extent_rec));
 196                 memset(HFS_I(inode)->cached_extents, 0, sizeof(hfs_extent_rec));
 197         }
 198         insert_inode_hash(inode);
 199         mark_inode_dirty(inode);
 200         set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
 201         sb->s_dirt = 1;
 202
 203         return inode;
 204 }
 205
 206 void hfs_delete_inode(struct inode *inode)
 207 {
 208         struct super_block *sb = inode->i_sb;
 209
 210         dprint(DBG_INODE, "delete_inode: %lu\n", inode->i_ino);
 211         if (S_ISDIR(inode->i_mode)) {
 212                 HFS_SB(sb)->folder_count--;
 213                 if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
 214                         HFS_SB(sb)->root_dirs--;
 215                 set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
 216                 sb->s_dirt = 1;
 217                 return;
 218         }
 219         HFS_SB(sb)->file_count--;
 220         if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
 221                 HFS_SB(sb)->root_files--;
 222         if (S_ISREG(inode->i_mode)) {
 223                 if (!inode->i_nlink) {
 224                         inode->i_size = 0;
 225                         hfs_file_truncate(inode);
 226                 }
 227         }
 228         set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
 229         sb->s_dirt = 1;
 230 }
 231
 232 void hfs_inode_read_fork(struct inode *inode, struct hfs_extent *ext,
 233                          __be32 __log_size, __be32 phys_size, u32 clump_size)
 234 {
 235         struct super_block *sb = inode->i_sb;
 236         u32 log_size = be32_to_cpu(__log_size);
 237         u16 count;
 238         int i;
 239
 240         memcpy(HFS_I(inode)->first_extents, ext, sizeof(hfs_extent_rec));
 241         for (count = 0, i = 0; i < 3; i++)
 242                 count += be16_to_cpu(ext[i].count);
 243         HFS_I(inode)->first_blocks = count;
 244
 245         inode->i_size = HFS_I(inode)->phys_size = log_size;
 246         inode->i_blocks = (log_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
 247         HFS_I(inode)->alloc_blocks = be32_to_cpu(phys_size) /
 248                                      HFS_SB(sb)->alloc_blksz;
 249         HFS_I(inode)->clump_blocks = clump_size / HFS_SB(sb)->alloc_blksz;
 250         if (!HFS_I(inode)->clump_blocks)
 251                 HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
 252 }
 253
 254 struct hfs_iget_data {
 255         struct hfs_cat_key *key;
 256         hfs_cat_rec *rec;
 257 };
 258
 259 int hfs_test_inode(struct inode *inode, void *data)
 260 {
 261         struct hfs_iget_data *idata = data;
 262         hfs_cat_rec *rec;
 263
 264         rec = idata->rec;
 265         switch (rec->type) {
 266         case HFS_CDR_DIR:
 267                 return inode->i_ino == be32_to_cpu(rec->dir.DirID);
 268         case HFS_CDR_FIL:
 269                 return inode->i_ino == be32_to_cpu(rec->file.FlNum);
 270         default:
 271                 BUG();
 272                 return 1;
 273         }
 274 }
 275
 276 /*
 277  * hfs_read_inode
 278  */
 279 int hfs_read_inode(struct inode *inode, void *data)
 280 {
 281         struct hfs_iget_data *idata = data;
 282         struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
 283         hfs_cat_rec *rec;
 284
 285         HFS_I(inode)->flags = 0;
 286         HFS_I(inode)->rsrc_inode = NULL;
 287         init_MUTEX(&HFS_I(inode)->extents_lock);
 288         INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
 289
 290         /* Initialize the inode */
 291         inode->i_uid = hsb->s_uid;
 292         inode->i_gid = hsb->s_gid;
 293         inode->i_nlink = 1;
 294
 295         if (idata->key)
 296                 HFS_I(inode)->cat_key = *idata->key;
 297         else
 298                 HFS_I(inode)->flags |= HFS_FLG_RSRC;
 299         HFS_I(inode)->tz_secondswest = sys_tz.tz_minuteswest * 60;
 300
 301         rec = idata->rec;
 302         switch (rec->type) {
 303         case HFS_CDR_FIL:
 304                 if (!HFS_IS_RSRC(inode)) {
 305                         hfs_inode_read_fork(inode, rec->file.ExtRec, rec->file.LgLen,
 306                                             rec->file.PyLen, be16_to_cpu(rec->file.ClpSize));
 307                 } else {
 308                         hfs_inode_read_fork(inode, rec->file.RExtRec, rec->file.RLgLen,
 309                                             rec->file.RPyLen, be16_to_cpu(rec->file.ClpSize));
 310                 }
 311
 312                 inode->i_ino = be32_to_cpu(rec->file.FlNum);
 313                 inode->i_mode = S_IRUGO | S_IXUGO;
 314                 if (!(rec->file.Flags & HFS_FIL_LOCK))
 315                         inode->i_mode |= S_IWUGO;
 316                 inode->i_mode &= hsb->s_file_umask;
 317                 inode->i_mode |= S_IFREG;
 318                 inode->i_ctime = inode->i_atime = inode->i_mtime =
 319                                 hfs_m_to_utime(rec->file.MdDat);
 320                 inode->i_op = &hfs_file_inode_operations;
 321                 inode->i_fop = &hfs_file_operations;
 322                 inode->i_mapping->a_ops = &hfs_aops;
 323                 HFS_I(inode)->phys_size = inode->i_size;
 324                 break;
 325         case HFS_CDR_DIR:
 326                 inode->i_ino = be32_to_cpu(rec->dir.DirID);
 327                 inode->i_blocks = 0;
 328                 inode->i_size = be16_to_cpu(rec->dir.Val) + 2;
 329                 inode->i_mode = S_IFDIR | (S_IRWXUGO & hsb->s_dir_umask);
 330                 inode->i_ctime = inode->i_atime = inode->i_mtime =
 331                                 hfs_m_to_utime(rec->file.MdDat);
 332                 inode->i_op = &hfs_dir_inode_operations;
 333                 inode->i_fop = &hfs_dir_operations;
 334                 break;
 335         default:
 336                 make_bad_inode(inode);
 337         }
 338         return 0;
 339 }
 340
 341 /*
 342  * __hfs_iget()
 343  *
 344  * Given the MDB for a HFS filesystem, a 'key' and an 'entry' in
 345  * the catalog B-tree and the 'type' of the desired file return the
 346  * inode for that file/directory or NULL.  Note that 'type' indicates
 347  * whether we want the actual file or directory, or the corresponding
 348  * metadata (AppleDouble header file or CAP metadata file).
 349  */
 350 struct inode *hfs_iget(struct super_block *sb, struct hfs_cat_key *key, hfs_cat_rec *rec)
 351 {
 352         struct hfs_iget_data data = { key, rec };
 353         struct inode *inode;
 354         u32 cnid;
 355
 356         switch (rec->type) {
 357         case HFS_CDR_DIR:
 358                 cnid = be32_to_cpu(rec->dir.DirID);
 359                 break;
 360         case HFS_CDR_FIL:
 361                 cnid = be32_to_cpu(rec->file.FlNum);
 362                 break;
 363         default:
 364                 return NULL;
 365         }
 366         inode = iget5_locked(sb, cnid, hfs_test_inode, hfs_read_inode, &data);
 367         if (inode && (inode->i_state & I_NEW))
 368                 unlock_new_inode(inode);
 369         return inode;
 370 }
 371
 372 void hfs_inode_write_fork(struct inode *inode, struct hfs_extent *ext,
 373                           __be32 *log_size, __be32 *phys_size)
 374 {
 375         memcpy(ext, HFS_I(inode)->first_extents, sizeof(hfs_extent_rec));
 376
 377         if (log_size)
 378                 *log_size = cpu_to_be32(inode->i_size);
 379         if (phys_size)
 380                 *phys_size = cpu_to_be32(HFS_I(inode)->alloc_blocks *
 381                                          HFS_SB(inode->i_sb)->alloc_blksz);
 382 }
 383
 384 int hfs_write_inode(struct inode *inode, int unused)
 385 {
 386         struct hfs_find_data fd;
 387         hfs_cat_rec rec;
 388
 389         dprint(DBG_INODE, "hfs_write_inode: %lu\n", inode->i_ino);
 390         hfs_ext_write_extent(inode);
 391
 392         if (inode->i_ino < HFS_FIRSTUSER_CNID) {
 393                 switch (inode->i_ino) {
 394                 case HFS_ROOT_CNID:
 395                         break;
 396                 case HFS_EXT_CNID:
 397                         hfs_btree_write(HFS_SB(inode->i_sb)->ext_tree);
 398                         return 0;
 399                 case HFS_CAT_CNID:
 400                         hfs_btree_write(HFS_SB(inode->i_sb)->cat_tree);
 401                         return 0;
 402                 default:
 403                         BUG();
 404                         return -EIO;
 405                 }
 406         }
 407
 408         if (HFS_IS_RSRC(inode)) {
 409                 mark_inode_dirty(HFS_I(inode)->rsrc_inode);
 410                 return 0;
 411         }
 412
 413         if (!inode->i_nlink)
 414                 return 0;
 415
 416         if (hfs_find_init(HFS_SB(inode->i_sb)->cat_tree, &fd))
 417                 /* panic? */
 418                 return -EIO;
 419
 420         fd.search_key->cat = HFS_I(inode)->cat_key;
 421         if (hfs_brec_find(&fd))
 422                 /* panic? */
 423                 goto out;
 424
 425         if (S_ISDIR(inode->i_mode)) {
 426                 if (fd.entrylength < sizeof(struct hfs_cat_dir))
 427                         /* panic? */;
 428                 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
 429                            sizeof(struct hfs_cat_dir));
 430                 if (rec.type != HFS_CDR_DIR ||
 431                     be32_to_cpu(rec.dir.DirID) != inode->i_ino) {
 432                 }
 433
 434                 rec.dir.MdDat = hfs_u_to_mtime(inode->i_mtime);
 435                 rec.dir.Val = cpu_to_be16(inode->i_size - 2);
 436
 437                 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
 438                             sizeof(struct hfs_cat_dir));
 439         } else {
 440                 if (fd.entrylength < sizeof(struct hfs_cat_file))
 441                         /* panic? */;
 442                 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
 443                            sizeof(struct hfs_cat_file));
 444                 if (rec.type != HFS_CDR_FIL ||
 445                     be32_to_cpu(rec.file.FlNum) != inode->i_ino) {
 446                 }
 447
 448                 if (inode->i_mode & S_IWUSR)
 449                         rec.file.Flags &= ~HFS_FIL_LOCK;
 450                 else
 451                         rec.file.Flags |= HFS_FIL_LOCK;
 452                 hfs_inode_write_fork(inode, rec.file.ExtRec, &rec.file.LgLen, &rec.file.PyLen);
 453                 if (HFS_I(inode)->rsrc_inode)
 454                         hfs_inode_write_fork(HFS_I(inode)->rsrc_inode, rec.file.RExtRec,
 455                                              &rec.file.RLgLen, &rec.file.RPyLen);
 456                 rec.file.MdDat = hfs_u_to_mtime(inode->i_mtime);
 457
 458                 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
 459                             sizeof(struct hfs_cat_file));
 460         }
 461 out:
 462         hfs_find_exit(&fd);
 463         return 0;
 464 }
 465
 466 static struct dentry *hfs_file_lookup(struct inode *dir, struct dentry *dentry,
 467                                       struct nameidata *nd)
 468 {
 469         struct inode *inode = NULL;
 470         hfs_cat_rec rec;
 471         struct hfs_find_data fd;
 472         int res;
 473
 474         if (HFS_IS_RSRC(dir) || strcmp(dentry->d_name.name, "rsrc"))
 475                 goto out;
 476
 477         inode = HFS_I(dir)->rsrc_inode;
 478         if (inode)
 479                 goto out;
 480
 481         inode = new_inode(dir->i_sb);
 482         if (!inode)
 483                 return ERR_PTR(-ENOMEM);
 484
 485         hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
 486         fd.search_key->cat = HFS_I(dir)->cat_key;
 487         res = hfs_brec_read(&fd, &rec, sizeof(rec));
 488         if (!res) {
 489                 struct hfs_iget_data idata = { NULL, &rec };
 490                 hfs_read_inode(inode, &idata);
 491         }
 492         hfs_find_exit(&fd);
 493         if (res) {
 494                 iput(inode);
 495                 return ERR_PTR(res);
 496         }
 497         HFS_I(inode)->rsrc_inode = dir;
 498         HFS_I(dir)->rsrc_inode = inode;
 499         igrab(dir);
 500         hlist_add_head(&inode->i_hash, &HFS_SB(dir->i_sb)->rsrc_inodes);
 501         mark_inode_dirty(inode);
 502 out:
 503         d_add(dentry, inode);
 504         return NULL;
 505 }
 506
 507 void hfs_clear_inode(struct inode *inode)
 508 {
 509         if (HFS_IS_RSRC(inode) && HFS_I(inode)->rsrc_inode) {
 510                 HFS_I(HFS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
 511                 iput(HFS_I(inode)->rsrc_inode);
 512         }
 513 }
 514
 515 static int hfs_permission(struct inode *inode, int mask,
 516                           struct nameidata *nd)
 517 {
 518         if (S_ISREG(inode->i_mode) && mask & MAY_EXEC)
 519                 return 0;
 520         return vfs_permission(inode, mask);
 521 }
 522
 523 static int hfs_file_open(struct inode *inode, struct file *file)
 524 {
 525         if (HFS_IS_RSRC(inode))
 526                 inode = HFS_I(inode)->rsrc_inode;
 527         if (atomic_read(&file->f_count) != 1)
 528                 return 0;
 529         atomic_inc(&HFS_I(inode)->opencnt);
 530         return 0;
 531 }
 532
 533 static int hfs_file_release(struct inode *inode, struct file *file)
 534 {
 535         //struct super_block *sb = inode->i_sb;
 536
 537         if (HFS_IS_RSRC(inode))
 538                 inode = HFS_I(inode)->rsrc_inode;
 539         if (atomic_read(&file->f_count) != 0)
 540                 return 0;
 541         if (atomic_dec_and_test(&HFS_I(inode)->opencnt)) {
 542                 down(&inode->i_sem);
 543                 hfs_file_truncate(inode);
 544                 //if (inode->i_flags & S_DEAD) {
 545                 //      hfs_delete_cat(inode->i_ino, HFSPLUS_SB(sb).hidden_dir, NULL);
 546                 //      hfs_delete_inode(inode);
 547                 //}
 548                 up(&inode->i_sem);
 549         }
 550         return 0;
 551 }
 552
 553 /*
 554  * hfs_notify_change()
 555  *
 556  * Based very closely on fs/msdos/inode.c by Werner Almesberger
 557  *
 558  * This is the notify_change() field in the super_operations structure
 559  * for HFS file systems.  The purpose is to take that changes made to
 560  * an inode and apply then in a filesystem-dependent manner.  In this
 561  * case the process has a few of tasks to do:
 562  *  1) prevent changes to the i_uid and i_gid fields.
 563  *  2) map file permissions to the closest allowable permissions
 564  *  3) Since multiple Linux files can share the same on-disk inode under
 565  *     HFS (for instance the data and resource forks of a file) a change
 566  *     to permissions must be applied to all other in-core inodes which
 567  *     correspond to the same HFS file.
 568  */
 569
 570 int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
 571 {
 572         struct inode *inode = dentry->d_inode;
 573         struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
 574         int error;
 575
 576         error = inode_change_ok(inode, attr); /* basic permission checks */
 577         if (error)
 578                 return error;
 579
 580         /* no uig/gid changes and limit which mode bits can be set */
 581         if (((attr->ia_valid & ATTR_UID) &&
 582              (attr->ia_uid != hsb->s_uid)) ||
 583             ((attr->ia_valid & ATTR_GID) &&
 584              (attr->ia_gid != hsb->s_gid)) ||
 585             ((attr->ia_valid & ATTR_MODE) &&
 586              ((S_ISDIR(inode->i_mode) &&
 587                (attr->ia_mode != inode->i_mode)) ||
 588               (attr->ia_mode & ~HFS_VALID_MODE_BITS)))) {
 589                 return hsb->s_quiet ? 0 : error;
 590         }
 591
 592         if (attr->ia_valid & ATTR_MODE) {
 593                 /* Only the 'w' bits can ever change and only all together. */
 594                 if (attr->ia_mode & S_IWUSR)
 595                         attr->ia_mode = inode->i_mode | S_IWUGO;
 596                 else
 597                         attr->ia_mode = inode->i_mode & ~S_IWUGO;
 598                 attr->ia_mode &= S_ISDIR(inode->i_mode) ? ~hsb->s_dir_umask: ~hsb->s_file_umask;
 599         }
 600         error = inode_setattr(inode, attr);
 601         if (error)
 602                 return error;
 603
 604         return 0;
 605 }
 606
 607
 608 struct file_operations hfs_file_operations = {
 609         .llseek         = generic_file_llseek,
 610         .read           = generic_file_read,
 611         .write          = generic_file_write,
 612         .mmap           = generic_file_mmap,
 613         .sendfile       = generic_file_sendfile,
 614         .fsync          = file_fsync,
 615         .open           = hfs_file_open,
 616         .release        = hfs_file_release,
 617 };
 618
 619 struct inode_operations hfs_file_inode_operations = {
 620         .lookup         = hfs_file_lookup,
 621         .truncate       = hfs_file_truncate,
 622         .setattr        = hfs_inode_setattr,
 623         .permission     = hfs_permission,
 624 };