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/mpage.h>
  16 #include <linux/sched.h>
  17
  18 #include "hfs_fs.h"
  19 #include "btree.h"
  20
  21 static const struct file_operations hfs_file_operations;
  22 static const struct inode_operations hfs_file_inode_operations;
  23
  24 /*================ Variable-like macros ================*/
  25
  26 #define HFS_VALID_MODE_BITS  (S_IFREG | S_IFDIR | S_IRWXUGO)
  27
  28 static int hfs_writepage(struct page *page, struct writeback_control *wbc)
  29 {
  30         return block_write_full_page(page, hfs_get_block, wbc);
  31 }
  32
  33 static int hfs_readpage(struct file *file, struct page *page)
  34 {
  35         return block_read_full_page(page, hfs_get_block);
  36 }
  37
  38 static void hfs_write_failed(struct address_space *mapping, loff_t to)
  39 {
  40         struct inode *inode = mapping->host;
  41
  42         if (to > inode->i_size) {
  43                 truncate_pagecache(inode, to, inode->i_size);
  44                 hfs_file_truncate(inode);
  45         }
  46 }
  47
  48 static int hfs_write_begin(struct file *file, struct address_space *mapping,
  49                         loff_t pos, unsigned len, unsigned flags,
  50                         struct page **pagep, void **fsdata)
  51 {
  52         int ret;
  53
  54         *pagep = NULL;
  55         ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
  56                                 hfs_get_block,
  57                                 &HFS_I(mapping->host)->phys_size);
  58         if (unlikely(ret))
  59                 hfs_write_failed(mapping, pos + len);
  60
  61         return ret;
  62 }
  63
  64 static sector_t hfs_bmap(struct address_space *mapping, sector_t block)
  65 {
  66         return generic_block_bmap(mapping, block, hfs_get_block);
  67 }
  68
  69 static int hfs_releasepage(struct page *page, gfp_t mask)
  70 {
  71         struct inode *inode = page->mapping->host;
  72         struct super_block *sb = inode->i_sb;
  73         struct hfs_btree *tree;
  74         struct hfs_bnode *node;
  75         u32 nidx;
  76         int i, res = 1;
  77
  78         switch (inode->i_ino) {
  79         case HFS_EXT_CNID:
  80                 tree = HFS_SB(sb)->ext_tree;
  81                 break;
  82         case HFS_CAT_CNID:
  83                 tree = HFS_SB(sb)->cat_tree;
  84                 break;
  85         default:
  86                 BUG();
  87                 return 0;
  88         }
  89
  90         if (!tree)
  91                 return 0;
  92
  93         if (tree->node_size >= PAGE_CACHE_SIZE) {
  94                 nidx = page->index >> (tree->node_size_shift - PAGE_CACHE_SHIFT);
  95                 spin_lock(&tree->hash_lock);
  96                 node = hfs_bnode_findhash(tree, nidx);
  97                 if (!node)
  98                         ;
  99                 else if (atomic_read(&node->refcnt))
 100                         res = 0;
 101                 if (res && node) {
 102                         hfs_bnode_unhash(node);
 103                         hfs_bnode_free(node);
 104                 }
 105                 spin_unlock(&tree->hash_lock);
 106         } else {
 107                 nidx = page->index << (PAGE_CACHE_SHIFT - tree->node_size_shift);
 108                 i = 1 << (PAGE_CACHE_SHIFT - tree->node_size_shift);
 109                 spin_lock(&tree->hash_lock);
 110                 do {
 111                         node = hfs_bnode_findhash(tree, nidx++);
 112                         if (!node)
 113                                 continue;
 114                         if (atomic_read(&node->refcnt)) {
 115                                 res = 0;
 116                                 break;
 117                         }
 118                         hfs_bnode_unhash(node);
 119                         hfs_bnode_free(node);
 120                 } while (--i && nidx < tree->node_count);
 121                 spin_unlock(&tree->hash_lock);
 122         }
 123         return res ? try_to_free_buffers(page) : 0;
 124 }
 125
 126 static ssize_t hfs_direct_IO(int rw, struct kiocb *iocb,
 127                 const struct iovec *iov, loff_t offset, unsigned long nr_segs)
 128 {
 129         struct file *file = iocb->ki_filp;
 130         struct address_space *mapping = file->f_mapping;
 131         struct inode *inode = file_inode(file)->i_mapping->host;
 132         ssize_t ret;
 133
 134         ret = blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
 135                                  hfs_get_block);
 136
 137         /*
 138          * In case of error extending write may have instantiated a few
 139          * blocks outside i_size. Trim these off again.
 140          */
 141         if (unlikely((rw & WRITE) && ret < 0)) {
 142                 loff_t isize = i_size_read(inode);
 143                 loff_t end = offset + iov_length(iov, nr_segs);
 144
 145                 if (end > isize)
 146                         hfs_write_failed(mapping, end);
 147         }
 148
 149         return ret;
 150 }
 151
 152 static int hfs_writepages(struct address_space *mapping,
 153                           struct writeback_control *wbc)
 154 {
 155         return mpage_writepages(mapping, wbc, hfs_get_block);
 156 }
 157
 158 const struct address_space_operations hfs_btree_aops = {
 159         .readpage       = hfs_readpage,
 160         .writepage      = hfs_writepage,
 161         .write_begin    = hfs_write_begin,
 162         .write_end      = generic_write_end,
 163         .bmap           = hfs_bmap,
 164         .releasepage    = hfs_releasepage,
 165 };
 166
 167 const struct address_space_operations hfs_aops = {
 168         .readpage       = hfs_readpage,
 169         .writepage      = hfs_writepage,
 170         .write_begin    = hfs_write_begin,
 171         .write_end      = generic_write_end,
 172         .bmap           = hfs_bmap,
 173         .direct_IO      = hfs_direct_IO,
 174         .writepages     = hfs_writepages,
 175 };
 176
 177 /*
 178  * hfs_new_inode
 179  */
 180 struct inode *hfs_new_inode(struct inode *dir, struct qstr *name, umode_t mode)
 181 {
 182         struct super_block *sb = dir->i_sb;
 183         struct inode *inode = new_inode(sb);
 184         if (!inode)
 185                 return NULL;
 186
 187         mutex_init(&HFS_I(inode)->extents_lock);
 188         INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
 189         hfs_cat_build_key(sb, (btree_key *)&HFS_I(inode)->cat_key, dir->i_ino, name);
 190         inode->i_ino = HFS_SB(sb)->next_id++;
 191         inode->i_mode = mode;
 192         inode->i_uid = current_fsuid();
 193         inode->i_gid = current_fsgid();
 194         set_nlink(inode, 1);
 195         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
 196         HFS_I(inode)->flags = 0;
 197         HFS_I(inode)->rsrc_inode = NULL;
 198         HFS_I(inode)->fs_blocks = 0;
 199         if (S_ISDIR(mode)) {
 200                 inode->i_size = 2;
 201                 HFS_SB(sb)->folder_count++;
 202                 if (dir->i_ino == HFS_ROOT_CNID)
 203                         HFS_SB(sb)->root_dirs++;
 204                 inode->i_op = &hfs_dir_inode_operations;
 205                 inode->i_fop = &hfs_dir_operations;
 206                 inode->i_mode |= S_IRWXUGO;
 207                 inode->i_mode &= ~HFS_SB(inode->i_sb)->s_dir_umask;
 208         } else if (S_ISREG(mode)) {
 209                 HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
 210                 HFS_SB(sb)->file_count++;
 211                 if (dir->i_ino == HFS_ROOT_CNID)
 212                         HFS_SB(sb)->root_files++;
 213                 inode->i_op = &hfs_file_inode_operations;
 214                 inode->i_fop = &hfs_file_operations;
 215                 inode->i_mapping->a_ops = &hfs_aops;
 216                 inode->i_mode |= S_IRUGO|S_IXUGO;
 217                 if (mode & S_IWUSR)
 218                         inode->i_mode |= S_IWUGO;
 219                 inode->i_mode &= ~HFS_SB(inode->i_sb)->s_file_umask;
 220                 HFS_I(inode)->phys_size = 0;
 221                 HFS_I(inode)->alloc_blocks = 0;
 222                 HFS_I(inode)->first_blocks = 0;
 223                 HFS_I(inode)->cached_start = 0;
 224                 HFS_I(inode)->cached_blocks = 0;
 225                 memset(HFS_I(inode)->first_extents, 0, sizeof(hfs_extent_rec));
 226                 memset(HFS_I(inode)->cached_extents, 0, sizeof(hfs_extent_rec));
 227         }
 228         insert_inode_hash(inode);
 229         mark_inode_dirty(inode);
 230         set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
 231         hfs_mark_mdb_dirty(sb);
 232
 233         return inode;
 234 }
 235
 236 void hfs_delete_inode(struct inode *inode)
 237 {
 238         struct super_block *sb = inode->i_sb;
 239
 240         dprint(DBG_INODE, "delete_inode: %lu\n", inode->i_ino);
 241         if (S_ISDIR(inode->i_mode)) {
 242                 HFS_SB(sb)->folder_count--;
 243                 if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
 244                         HFS_SB(sb)->root_dirs--;
 245                 set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
 246                 hfs_mark_mdb_dirty(sb);
 247                 return;
 248         }
 249         HFS_SB(sb)->file_count--;
 250         if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID))
 251                 HFS_SB(sb)->root_files--;
 252         if (S_ISREG(inode->i_mode)) {
 253                 if (!inode->i_nlink) {
 254                         inode->i_size = 0;
 255                         hfs_file_truncate(inode);
 256                 }
 257         }
 258         set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags);
 259         hfs_mark_mdb_dirty(sb);
 260 }
 261
 262 void hfs_inode_read_fork(struct inode *inode, struct hfs_extent *ext,
 263                          __be32 __log_size, __be32 phys_size, u32 clump_size)
 264 {
 265         struct super_block *sb = inode->i_sb;
 266         u32 log_size = be32_to_cpu(__log_size);
 267         u16 count;
 268         int i;
 269
 270         memcpy(HFS_I(inode)->first_extents, ext, sizeof(hfs_extent_rec));
 271         for (count = 0, i = 0; i < 3; i++)
 272                 count += be16_to_cpu(ext[i].count);
 273         HFS_I(inode)->first_blocks = count;
 274
 275         inode->i_size = HFS_I(inode)->phys_size = log_size;
 276         HFS_I(inode)->fs_blocks = (log_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits;
 277         inode_set_bytes(inode, HFS_I(inode)->fs_blocks << sb->s_blocksize_bits);
 278         HFS_I(inode)->alloc_blocks = be32_to_cpu(phys_size) /
 279                                      HFS_SB(sb)->alloc_blksz;
 280         HFS_I(inode)->clump_blocks = clump_size / HFS_SB(sb)->alloc_blksz;
 281         if (!HFS_I(inode)->clump_blocks)
 282                 HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks;
 283 }
 284
 285 struct hfs_iget_data {
 286         struct hfs_cat_key *key;
 287         hfs_cat_rec *rec;
 288 };
 289
 290 static int hfs_test_inode(struct inode *inode, void *data)
 291 {
 292         struct hfs_iget_data *idata = data;
 293         hfs_cat_rec *rec;
 294
 295         rec = idata->rec;
 296         switch (rec->type) {
 297         case HFS_CDR_DIR:
 298                 return inode->i_ino == be32_to_cpu(rec->dir.DirID);
 299         case HFS_CDR_FIL:
 300                 return inode->i_ino == be32_to_cpu(rec->file.FlNum);
 301         default:
 302                 BUG();
 303                 return 1;
 304         }
 305 }
 306
 307 /*
 308  * hfs_read_inode
 309  */
 310 static int hfs_read_inode(struct inode *inode, void *data)
 311 {
 312         struct hfs_iget_data *idata = data;
 313         struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
 314         hfs_cat_rec *rec;
 315
 316         HFS_I(inode)->flags = 0;
 317         HFS_I(inode)->rsrc_inode = NULL;
 318         mutex_init(&HFS_I(inode)->extents_lock);
 319         INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list);
 320
 321         /* Initialize the inode */
 322         inode->i_uid = hsb->s_uid;
 323         inode->i_gid = hsb->s_gid;
 324         set_nlink(inode, 1);
 325
 326         if (idata->key)
 327                 HFS_I(inode)->cat_key = *idata->key;
 328         else
 329                 HFS_I(inode)->flags |= HFS_FLG_RSRC;
 330         HFS_I(inode)->tz_secondswest = sys_tz.tz_minuteswest * 60;
 331
 332         rec = idata->rec;
 333         switch (rec->type) {
 334         case HFS_CDR_FIL:
 335                 if (!HFS_IS_RSRC(inode)) {
 336                         hfs_inode_read_fork(inode, rec->file.ExtRec, rec->file.LgLen,
 337                                             rec->file.PyLen, be16_to_cpu(rec->file.ClpSize));
 338                 } else {
 339                         hfs_inode_read_fork(inode, rec->file.RExtRec, rec->file.RLgLen,
 340                                             rec->file.RPyLen, be16_to_cpu(rec->file.ClpSize));
 341                 }
 342
 343                 inode->i_ino = be32_to_cpu(rec->file.FlNum);
 344                 inode->i_mode = S_IRUGO | S_IXUGO;
 345                 if (!(rec->file.Flags & HFS_FIL_LOCK))
 346                         inode->i_mode |= S_IWUGO;
 347                 inode->i_mode &= ~hsb->s_file_umask;
 348                 inode->i_mode |= S_IFREG;
 349                 inode->i_ctime = inode->i_atime = inode->i_mtime =
 350                                 hfs_m_to_utime(rec->file.MdDat);
 351                 inode->i_op = &hfs_file_inode_operations;
 352                 inode->i_fop = &hfs_file_operations;
 353                 inode->i_mapping->a_ops = &hfs_aops;
 354                 break;
 355         case HFS_CDR_DIR:
 356                 inode->i_ino = be32_to_cpu(rec->dir.DirID);
 357                 inode->i_size = be16_to_cpu(rec->dir.Val) + 2;
 358                 HFS_I(inode)->fs_blocks = 0;
 359                 inode->i_mode = S_IFDIR | (S_IRWXUGO & ~hsb->s_dir_umask);
 360                 inode->i_ctime = inode->i_atime = inode->i_mtime =
 361                                 hfs_m_to_utime(rec->dir.MdDat);
 362                 inode->i_op = &hfs_dir_inode_operations;
 363                 inode->i_fop = &hfs_dir_operations;
 364                 break;
 365         default:
 366                 make_bad_inode(inode);
 367         }
 368         return 0;
 369 }
 370
 371 /*
 372  * __hfs_iget()
 373  *
 374  * Given the MDB for a HFS filesystem, a 'key' and an 'entry' in
 375  * the catalog B-tree and the 'type' of the desired file return the
 376  * inode for that file/directory or NULL.  Note that 'type' indicates
 377  * whether we want the actual file or directory, or the corresponding
 378  * metadata (AppleDouble header file or CAP metadata file).
 379  */
 380 struct inode *hfs_iget(struct super_block *sb, struct hfs_cat_key *key, hfs_cat_rec *rec)
 381 {
 382         struct hfs_iget_data data = { key, rec };
 383         struct inode *inode;
 384         u32 cnid;
 385
 386         switch (rec->type) {
 387         case HFS_CDR_DIR:
 388                 cnid = be32_to_cpu(rec->dir.DirID);
 389                 break;
 390         case HFS_CDR_FIL:
 391                 cnid = be32_to_cpu(rec->file.FlNum);
 392                 break;
 393         default:
 394                 return NULL;
 395         }
 396         inode = iget5_locked(sb, cnid, hfs_test_inode, hfs_read_inode, &data);
 397         if (inode && (inode->i_state & I_NEW))
 398                 unlock_new_inode(inode);
 399         return inode;
 400 }
 401
 402 void hfs_inode_write_fork(struct inode *inode, struct hfs_extent *ext,
 403                           __be32 *log_size, __be32 *phys_size)
 404 {
 405         memcpy(ext, HFS_I(inode)->first_extents, sizeof(hfs_extent_rec));
 406
 407         if (log_size)
 408                 *log_size = cpu_to_be32(inode->i_size);
 409         if (phys_size)
 410                 *phys_size = cpu_to_be32(HFS_I(inode)->alloc_blocks *
 411                                          HFS_SB(inode->i_sb)->alloc_blksz);
 412 }
 413
 414 int hfs_write_inode(struct inode *inode, struct writeback_control *wbc)
 415 {
 416         struct inode *main_inode = inode;
 417         struct hfs_find_data fd;
 418         hfs_cat_rec rec;
 419
 420         dprint(DBG_INODE, "hfs_write_inode: %lu\n", inode->i_ino);
 421         hfs_ext_write_extent(inode);
 422
 423         if (inode->i_ino < HFS_FIRSTUSER_CNID) {
 424                 switch (inode->i_ino) {
 425                 case HFS_ROOT_CNID:
 426                         break;
 427                 case HFS_EXT_CNID:
 428                         hfs_btree_write(HFS_SB(inode->i_sb)->ext_tree);
 429                         return 0;
 430                 case HFS_CAT_CNID:
 431                         hfs_btree_write(HFS_SB(inode->i_sb)->cat_tree);
 432                         return 0;
 433                 default:
 434                         BUG();
 435                         return -EIO;
 436                 }
 437         }
 438
 439         if (HFS_IS_RSRC(inode))
 440                 main_inode = HFS_I(inode)->rsrc_inode;
 441
 442         if (!main_inode->i_nlink)
 443                 return 0;
 444
 445         if (hfs_find_init(HFS_SB(main_inode->i_sb)->cat_tree, &fd))
 446                 /* panic? */
 447                 return -EIO;
 448
 449         fd.search_key->cat = HFS_I(main_inode)->cat_key;
 450         if (hfs_brec_find(&fd))
 451                 /* panic? */
 452                 goto out;
 453
 454         if (S_ISDIR(main_inode->i_mode)) {
 455                 if (fd.entrylength < sizeof(struct hfs_cat_dir))
 456                         /* panic? */;
 457                 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
 458                            sizeof(struct hfs_cat_dir));
 459                 if (rec.type != HFS_CDR_DIR ||
 460                     be32_to_cpu(rec.dir.DirID) != inode->i_ino) {
 461                 }
 462
 463                 rec.dir.MdDat = hfs_u_to_mtime(inode->i_mtime);
 464                 rec.dir.Val = cpu_to_be16(inode->i_size - 2);
 465
 466                 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
 467                             sizeof(struct hfs_cat_dir));
 468         } else if (HFS_IS_RSRC(inode)) {
 469                 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
 470                                sizeof(struct hfs_cat_file));
 471                 hfs_inode_write_fork(inode, rec.file.RExtRec,
 472                                      &rec.file.RLgLen, &rec.file.RPyLen);
 473                 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
 474                                 sizeof(struct hfs_cat_file));
 475         } else {
 476                 if (fd.entrylength < sizeof(struct hfs_cat_file))
 477                         /* panic? */;
 478                 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset,
 479                            sizeof(struct hfs_cat_file));
 480                 if (rec.type != HFS_CDR_FIL ||
 481                     be32_to_cpu(rec.file.FlNum) != inode->i_ino) {
 482                 }
 483
 484                 if (inode->i_mode & S_IWUSR)
 485                         rec.file.Flags &= ~HFS_FIL_LOCK;
 486                 else
 487                         rec.file.Flags |= HFS_FIL_LOCK;
 488                 hfs_inode_write_fork(inode, rec.file.ExtRec, &rec.file.LgLen, &rec.file.PyLen);
 489                 rec.file.MdDat = hfs_u_to_mtime(inode->i_mtime);
 490
 491                 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset,
 492                             sizeof(struct hfs_cat_file));
 493         }
 494 out:
 495         hfs_find_exit(&fd);
 496         return 0;
 497 }
 498
 499 static struct dentry *hfs_file_lookup(struct inode *dir, struct dentry *dentry,
 500                                       unsigned int flags)
 501 {
 502         struct inode *inode = NULL;
 503         hfs_cat_rec rec;
 504         struct hfs_find_data fd;
 505         int res;
 506
 507         if (HFS_IS_RSRC(dir) || strcmp(dentry->d_name.name, "rsrc"))
 508                 goto out;
 509
 510         inode = HFS_I(dir)->rsrc_inode;
 511         if (inode)
 512                 goto out;
 513
 514         inode = new_inode(dir->i_sb);
 515         if (!inode)
 516                 return ERR_PTR(-ENOMEM);
 517
 518         hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd);
 519         fd.search_key->cat = HFS_I(dir)->cat_key;
 520         res = hfs_brec_read(&fd, &rec, sizeof(rec));
 521         if (!res) {
 522                 struct hfs_iget_data idata = { NULL, &rec };
 523                 hfs_read_inode(inode, &idata);
 524         }
 525         hfs_find_exit(&fd);
 526         if (res) {
 527                 iput(inode);
 528                 return ERR_PTR(res);
 529         }
 530         HFS_I(inode)->rsrc_inode = dir;
 531         HFS_I(dir)->rsrc_inode = inode;
 532         igrab(dir);
 533         hlist_add_fake(&inode->i_hash);
 534         mark_inode_dirty(inode);
 535 out:
 536         d_add(dentry, inode);
 537         return NULL;
 538 }
 539
 540 void hfs_evict_inode(struct inode *inode)
 541 {
 542         truncate_inode_pages(&inode->i_data, 0);
 543         clear_inode(inode);
 544         if (HFS_IS_RSRC(inode) && HFS_I(inode)->rsrc_inode) {
 545                 HFS_I(HFS_I(inode)->rsrc_inode)->rsrc_inode = NULL;
 546                 iput(HFS_I(inode)->rsrc_inode);
 547         }
 548 }
 549
 550 static int hfs_file_open(struct inode *inode, struct file *file)
 551 {
 552         if (HFS_IS_RSRC(inode))
 553                 inode = HFS_I(inode)->rsrc_inode;
 554         atomic_inc(&HFS_I(inode)->opencnt);
 555         return 0;
 556 }
 557
 558 static int hfs_file_release(struct inode *inode, struct file *file)
 559 {
 560         //struct super_block *sb = inode->i_sb;
 561
 562         if (HFS_IS_RSRC(inode))
 563                 inode = HFS_I(inode)->rsrc_inode;
 564         if (atomic_dec_and_test(&HFS_I(inode)->opencnt)) {
 565                 mutex_lock(&inode->i_mutex);
 566                 hfs_file_truncate(inode);
 567                 //if (inode->i_flags & S_DEAD) {
 568                 //      hfs_delete_cat(inode->i_ino, HFSPLUS_SB(sb).hidden_dir, NULL);
 569                 //      hfs_delete_inode(inode);
 570                 //}
 571                 mutex_unlock(&inode->i_mutex);
 572         }
 573         return 0;
 574 }
 575
 576 /*
 577  * hfs_notify_change()
 578  *
 579  * Based very closely on fs/msdos/inode.c by Werner Almesberger
 580  *
 581  * This is the notify_change() field in the super_operations structure
 582  * for HFS file systems.  The purpose is to take that changes made to
 583  * an inode and apply then in a filesystem-dependent manner.  In this
 584  * case the process has a few of tasks to do:
 585  *  1) prevent changes to the i_uid and i_gid fields.
 586  *  2) map file permissions to the closest allowable permissions
 587  *  3) Since multiple Linux files can share the same on-disk inode under
 588  *     HFS (for instance the data and resource forks of a file) a change
 589  *     to permissions must be applied to all other in-core inodes which
 590  *     correspond to the same HFS file.
 591  */
 592
 593 int hfs_inode_setattr(struct dentry *dentry, struct iattr * attr)
 594 {
 595         struct inode *inode = dentry->d_inode;
 596         struct hfs_sb_info *hsb = HFS_SB(inode->i_sb);
 597         int error;
 598
 599         error = inode_change_ok(inode, attr); /* basic permission checks */
 600         if (error)
 601                 return error;
 602
 603         /* no uig/gid changes and limit which mode bits can be set */
 604         if (((attr->ia_valid & ATTR_UID) &&
 605              (!uid_eq(attr->ia_uid, hsb->s_uid))) ||
 606             ((attr->ia_valid & ATTR_GID) &&
 607              (!gid_eq(attr->ia_gid, hsb->s_gid))) ||
 608             ((attr->ia_valid & ATTR_MODE) &&
 609              ((S_ISDIR(inode->i_mode) &&
 610                (attr->ia_mode != inode->i_mode)) ||
 611               (attr->ia_mode & ~HFS_VALID_MODE_BITS)))) {
 612                 return hsb->s_quiet ? 0 : error;
 613         }
 614
 615         if (attr->ia_valid & ATTR_MODE) {
 616                 /* Only the 'w' bits can ever change and only all together. */
 617                 if (attr->ia_mode & S_IWUSR)
 618                         attr->ia_mode = inode->i_mode | S_IWUGO;
 619                 else
 620                         attr->ia_mode = inode->i_mode & ~S_IWUGO;
 621                 attr->ia_mode &= S_ISDIR(inode->i_mode) ? ~hsb->s_dir_umask: ~hsb->s_file_umask;
 622         }
 623
 624         if ((attr->ia_valid & ATTR_SIZE) &&
 625             attr->ia_size != i_size_read(inode)) {
 626                 inode_dio_wait(inode);
 627
 628                 error = inode_newsize_ok(inode, attr->ia_size);
 629                 if (error)
 630                         return error;
 631
 632                 truncate_setsize(inode, attr->ia_size);
 633                 hfs_file_truncate(inode);
 634         }
 635
 636         setattr_copy(inode, attr);
 637         mark_inode_dirty(inode);
 638         return 0;
 639 }
 640
 641 static int hfs_file_fsync(struct file *filp, loff_t start, loff_t end,
 642                           int datasync)
 643 {
 644         struct inode *inode = filp->f_mapping->host;
 645         struct super_block * sb;
 646         int ret, err;
 647
 648         ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
 649         if (ret)
 650                 return ret;
 651         mutex_lock(&inode->i_mutex);
 652
 653         /* sync the inode to buffers */
 654         ret = write_inode_now(inode, 0);
 655
 656         /* sync the superblock to buffers */
 657         sb = inode->i_sb;
 658         flush_delayed_work(&HFS_SB(sb)->mdb_work);
 659         /* .. finally sync the buffers to disk */
 660         err = sync_blockdev(sb->s_bdev);
 661         if (!ret)
 662                 ret = err;
 663         mutex_unlock(&inode->i_mutex);
 664         return ret;
 665 }
 666
 667 static const struct file_operations hfs_file_operations = {
 668         .llseek         = generic_file_llseek,
 669         .read           = do_sync_read,
 670         .aio_read       = generic_file_aio_read,
 671         .write          = do_sync_write,
 672         .aio_write      = generic_file_aio_write,
 673         .mmap           = generic_file_mmap,
 674         .splice_read    = generic_file_splice_read,
 675         .fsync          = hfs_file_fsync,
 676         .open           = hfs_file_open,
 677         .release        = hfs_file_release,
 678 };
 679
 680 static const struct inode_operations hfs_file_inode_operations = {
 681         .lookup         = hfs_file_lookup,
 682         .setattr        = hfs_inode_setattr,
 683         .setxattr       = hfs_setxattr,
 684         .getxattr       = hfs_getxattr,
 685         .listxattr      = hfs_listxattr,
 686 };