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 #include <linux/cred.h> 18 #include <linux/uio.h> 19 #include <linux/xattr.h> 20 #include <linux/blkdev.h> 21 22 #include "hfs_fs.h" 23 #include "btree.h" 24 25 static const struct file_operations hfs_file_operations; 26 static const struct inode_operations hfs_file_inode_operations; 27 28 /*================ Variable-like macros ================*/ 29 30 #define HFS_VALID_MODE_BITS (S_IFREG | S_IFDIR | S_IRWXUGO) 31 32 static int hfs_read_folio(struct file *file, struct folio *folio) 33 { 34 return block_read_full_folio(folio, hfs_get_block); 35 } 36 37 static void hfs_write_failed(struct address_space *mapping, loff_t to) 38 { 39 struct inode *inode = mapping->host; 40 41 if (to > inode->i_size) { 42 truncate_pagecache(inode, inode->i_size); 43 hfs_file_truncate(inode); 44 } 45 } 46 47 int hfs_write_begin(const struct kiocb *iocb, struct address_space *mapping, 48 loff_t pos, unsigned len, struct folio **foliop, void **fsdata) 49 { 50 int ret; 51 52 ret = cont_write_begin(iocb, mapping, pos, len, foliop, fsdata, 53 hfs_get_block, 54 &HFS_I(mapping->host)->phys_size); 55 if (unlikely(ret)) 56 hfs_write_failed(mapping, pos + len); 57 58 return ret; 59 } 60 61 static sector_t hfs_bmap(struct address_space *mapping, sector_t block) 62 { 63 return generic_block_bmap(mapping, block, hfs_get_block); 64 } 65 66 static bool hfs_release_folio(struct folio *folio, gfp_t mask) 67 { 68 struct inode *inode = folio->mapping->host; 69 struct super_block *sb = inode->i_sb; 70 struct hfs_btree *tree; 71 struct hfs_bnode *node; 72 u32 nidx; 73 int i; 74 bool res = true; 75 76 switch (inode->i_ino) { 77 case HFS_EXT_CNID: 78 tree = HFS_SB(sb)->ext_tree; 79 break; 80 case HFS_CAT_CNID: 81 tree = HFS_SB(sb)->cat_tree; 82 break; 83 default: 84 BUG(); 85 return false; 86 } 87 88 if (!tree) 89 return false; 90 91 if (tree->node_size >= PAGE_SIZE) { 92 nidx = folio->index >> (tree->node_size_shift - PAGE_SHIFT); 93 spin_lock(&tree->hash_lock); 94 node = hfs_bnode_findhash(tree, nidx); 95 if (!node) 96 ; 97 else if (atomic_read(&node->refcnt)) 98 res = false; 99 if (res && node) { 100 hfs_bnode_unhash(node); 101 hfs_bnode_free(node); 102 } 103 spin_unlock(&tree->hash_lock); 104 } else { 105 nidx = folio->index << (PAGE_SHIFT - tree->node_size_shift); 106 i = 1 << (PAGE_SHIFT - tree->node_size_shift); 107 spin_lock(&tree->hash_lock); 108 do { 109 node = hfs_bnode_findhash(tree, nidx++); 110 if (!node) 111 continue; 112 if (atomic_read(&node->refcnt)) { 113 res = false; 114 break; 115 } 116 hfs_bnode_unhash(node); 117 hfs_bnode_free(node); 118 } while (--i && nidx < tree->node_count); 119 spin_unlock(&tree->hash_lock); 120 } 121 return res ? try_to_free_buffers(folio) : false; 122 } 123 124 static ssize_t hfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) 125 { 126 struct file *file = iocb->ki_filp; 127 struct address_space *mapping = file->f_mapping; 128 struct inode *inode = mapping->host; 129 size_t count = iov_iter_count(iter); 130 ssize_t ret; 131 132 ret = blockdev_direct_IO(iocb, inode, iter, hfs_get_block); 133 134 /* 135 * In case of error extending write may have instantiated a few 136 * blocks outside i_size. Trim these off again. 137 */ 138 if (unlikely(iov_iter_rw(iter) == WRITE && ret < 0)) { 139 loff_t isize = i_size_read(inode); 140 loff_t end = iocb->ki_pos + count; 141 142 if (end > isize) 143 hfs_write_failed(mapping, end); 144 } 145 146 return ret; 147 } 148 149 static int hfs_writepages(struct address_space *mapping, 150 struct writeback_control *wbc) 151 { 152 return mpage_writepages(mapping, wbc, hfs_get_block); 153 } 154 155 const struct address_space_operations hfs_btree_aops = { 156 .dirty_folio = block_dirty_folio, 157 .invalidate_folio = block_invalidate_folio, 158 .read_folio = hfs_read_folio, 159 .writepages = hfs_writepages, 160 .write_begin = hfs_write_begin, 161 .write_end = generic_write_end, 162 .migrate_folio = buffer_migrate_folio, 163 .bmap = hfs_bmap, 164 .release_folio = hfs_release_folio, 165 }; 166 167 const struct address_space_operations hfs_aops = { 168 .dirty_folio = block_dirty_folio, 169 .invalidate_folio = block_invalidate_folio, 170 .read_folio = hfs_read_folio, 171 .write_begin = hfs_write_begin, 172 .write_end = generic_write_end, 173 .bmap = hfs_bmap, 174 .direct_IO = hfs_direct_IO, 175 .writepages = hfs_writepages, 176 .migrate_folio = buffer_migrate_folio, 177 }; 178 179 /* 180 * hfs_new_inode 181 */ 182 struct inode *hfs_new_inode(struct inode *dir, const struct qstr *name, umode_t mode) 183 { 184 struct super_block *sb = dir->i_sb; 185 struct inode *inode = new_inode(sb); 186 s64 next_id; 187 s64 file_count; 188 s64 folder_count; 189 190 if (!inode) 191 return NULL; 192 193 mutex_init(&HFS_I(inode)->extents_lock); 194 INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list); 195 spin_lock_init(&HFS_I(inode)->open_dir_lock); 196 hfs_cat_build_key(sb, (btree_key *)&HFS_I(inode)->cat_key, dir->i_ino, name); 197 next_id = atomic64_inc_return(&HFS_SB(sb)->next_id); 198 BUG_ON(next_id > U32_MAX); 199 inode->i_ino = (u32)next_id; 200 inode->i_mode = mode; 201 inode->i_uid = current_fsuid(); 202 inode->i_gid = current_fsgid(); 203 set_nlink(inode, 1); 204 simple_inode_init_ts(inode); 205 HFS_I(inode)->flags = 0; 206 HFS_I(inode)->rsrc_inode = NULL; 207 HFS_I(inode)->fs_blocks = 0; 208 HFS_I(inode)->tz_secondswest = sys_tz.tz_minuteswest * 60; 209 if (S_ISDIR(mode)) { 210 inode->i_size = 2; 211 folder_count = atomic64_inc_return(&HFS_SB(sb)->folder_count); 212 BUG_ON(folder_count > U32_MAX); 213 if (dir->i_ino == HFS_ROOT_CNID) 214 HFS_SB(sb)->root_dirs++; 215 inode->i_op = &hfs_dir_inode_operations; 216 inode->i_fop = &hfs_dir_operations; 217 inode->i_mode |= S_IRWXUGO; 218 inode->i_mode &= ~HFS_SB(inode->i_sb)->s_dir_umask; 219 } else if (S_ISREG(mode)) { 220 HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks; 221 file_count = atomic64_inc_return(&HFS_SB(sb)->file_count); 222 BUG_ON(file_count > U32_MAX); 223 if (dir->i_ino == HFS_ROOT_CNID) 224 HFS_SB(sb)->root_files++; 225 inode->i_op = &hfs_file_inode_operations; 226 inode->i_fop = &hfs_file_operations; 227 inode->i_mapping->a_ops = &hfs_aops; 228 inode->i_mode |= S_IRUGO|S_IXUGO; 229 if (mode & S_IWUSR) 230 inode->i_mode |= S_IWUGO; 231 inode->i_mode &= ~HFS_SB(inode->i_sb)->s_file_umask; 232 HFS_I(inode)->phys_size = 0; 233 HFS_I(inode)->alloc_blocks = 0; 234 HFS_I(inode)->first_blocks = 0; 235 HFS_I(inode)->cached_start = 0; 236 HFS_I(inode)->cached_blocks = 0; 237 memset(HFS_I(inode)->first_extents, 0, sizeof(hfs_extent_rec)); 238 memset(HFS_I(inode)->cached_extents, 0, sizeof(hfs_extent_rec)); 239 } 240 insert_inode_hash(inode); 241 mark_inode_dirty(inode); 242 set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags); 243 hfs_mark_mdb_dirty(sb); 244 245 return inode; 246 } 247 248 void hfs_delete_inode(struct inode *inode) 249 { 250 struct super_block *sb = inode->i_sb; 251 252 hfs_dbg("ino %lu\n", inode->i_ino); 253 if (S_ISDIR(inode->i_mode)) { 254 BUG_ON(atomic64_read(&HFS_SB(sb)->folder_count) > U32_MAX); 255 atomic64_dec(&HFS_SB(sb)->folder_count); 256 if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID)) 257 HFS_SB(sb)->root_dirs--; 258 set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags); 259 hfs_mark_mdb_dirty(sb); 260 return; 261 } 262 263 BUG_ON(atomic64_read(&HFS_SB(sb)->file_count) > U32_MAX); 264 atomic64_dec(&HFS_SB(sb)->file_count); 265 if (HFS_I(inode)->cat_key.ParID == cpu_to_be32(HFS_ROOT_CNID)) 266 HFS_SB(sb)->root_files--; 267 if (S_ISREG(inode->i_mode)) { 268 if (!inode->i_nlink) { 269 inode->i_size = 0; 270 hfs_file_truncate(inode); 271 } 272 } 273 set_bit(HFS_FLG_MDB_DIRTY, &HFS_SB(sb)->flags); 274 hfs_mark_mdb_dirty(sb); 275 } 276 277 void hfs_inode_read_fork(struct inode *inode, struct hfs_extent *ext, 278 __be32 __log_size, __be32 phys_size, u32 clump_size) 279 { 280 struct super_block *sb = inode->i_sb; 281 u32 log_size = be32_to_cpu(__log_size); 282 u16 count; 283 int i; 284 285 memcpy(HFS_I(inode)->first_extents, ext, sizeof(hfs_extent_rec)); 286 for (count = 0, i = 0; i < 3; i++) 287 count += be16_to_cpu(ext[i].count); 288 HFS_I(inode)->first_blocks = count; 289 HFS_I(inode)->cached_start = 0; 290 HFS_I(inode)->cached_blocks = 0; 291 292 inode->i_size = HFS_I(inode)->phys_size = log_size; 293 HFS_I(inode)->fs_blocks = (log_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits; 294 inode_set_bytes(inode, HFS_I(inode)->fs_blocks << sb->s_blocksize_bits); 295 HFS_I(inode)->alloc_blocks = be32_to_cpu(phys_size) / 296 HFS_SB(sb)->alloc_blksz; 297 HFS_I(inode)->clump_blocks = clump_size / HFS_SB(sb)->alloc_blksz; 298 if (!HFS_I(inode)->clump_blocks) 299 HFS_I(inode)->clump_blocks = HFS_SB(sb)->clumpablks; 300 } 301 302 struct hfs_iget_data { 303 struct hfs_cat_key *key; 304 hfs_cat_rec *rec; 305 }; 306 307 static int hfs_test_inode(struct inode *inode, void *data) 308 { 309 struct hfs_iget_data *idata = data; 310 hfs_cat_rec *rec; 311 312 rec = idata->rec; 313 switch (rec->type) { 314 case HFS_CDR_DIR: 315 return inode->i_ino == be32_to_cpu(rec->dir.DirID); 316 case HFS_CDR_FIL: 317 return inode->i_ino == be32_to_cpu(rec->file.FlNum); 318 default: 319 BUG(); 320 return 1; 321 } 322 } 323 324 /* 325 * hfs_read_inode 326 */ 327 static int hfs_read_inode(struct inode *inode, void *data) 328 { 329 struct hfs_iget_data *idata = data; 330 struct hfs_sb_info *hsb = HFS_SB(inode->i_sb); 331 hfs_cat_rec *rec; 332 333 HFS_I(inode)->flags = 0; 334 HFS_I(inode)->rsrc_inode = NULL; 335 mutex_init(&HFS_I(inode)->extents_lock); 336 INIT_LIST_HEAD(&HFS_I(inode)->open_dir_list); 337 spin_lock_init(&HFS_I(inode)->open_dir_lock); 338 339 /* Initialize the inode */ 340 inode->i_uid = hsb->s_uid; 341 inode->i_gid = hsb->s_gid; 342 set_nlink(inode, 1); 343 344 if (idata->key) 345 HFS_I(inode)->cat_key = *idata->key; 346 else 347 HFS_I(inode)->flags |= HFS_FLG_RSRC; 348 HFS_I(inode)->tz_secondswest = sys_tz.tz_minuteswest * 60; 349 350 rec = idata->rec; 351 switch (rec->type) { 352 case HFS_CDR_FIL: 353 if (!HFS_IS_RSRC(inode)) { 354 hfs_inode_read_fork(inode, rec->file.ExtRec, rec->file.LgLen, 355 rec->file.PyLen, be16_to_cpu(rec->file.ClpSize)); 356 } else { 357 hfs_inode_read_fork(inode, rec->file.RExtRec, rec->file.RLgLen, 358 rec->file.RPyLen, be16_to_cpu(rec->file.ClpSize)); 359 } 360 361 inode->i_ino = be32_to_cpu(rec->file.FlNum); 362 inode->i_mode = S_IRUGO | S_IXUGO; 363 if (!(rec->file.Flags & HFS_FIL_LOCK)) 364 inode->i_mode |= S_IWUGO; 365 inode->i_mode &= ~hsb->s_file_umask; 366 inode->i_mode |= S_IFREG; 367 inode_set_mtime_to_ts(inode, 368 inode_set_atime_to_ts(inode, inode_set_ctime_to_ts(inode, hfs_m_to_utime(rec->file.MdDat)))); 369 inode->i_op = &hfs_file_inode_operations; 370 inode->i_fop = &hfs_file_operations; 371 inode->i_mapping->a_ops = &hfs_aops; 372 break; 373 case HFS_CDR_DIR: 374 inode->i_ino = be32_to_cpu(rec->dir.DirID); 375 inode->i_size = be16_to_cpu(rec->dir.Val) + 2; 376 HFS_I(inode)->fs_blocks = 0; 377 inode->i_mode = S_IFDIR | (S_IRWXUGO & ~hsb->s_dir_umask); 378 inode_set_mtime_to_ts(inode, 379 inode_set_atime_to_ts(inode, inode_set_ctime_to_ts(inode, hfs_m_to_utime(rec->dir.MdDat)))); 380 inode->i_op = &hfs_dir_inode_operations; 381 inode->i_fop = &hfs_dir_operations; 382 break; 383 default: 384 make_bad_inode(inode); 385 } 386 return 0; 387 } 388 389 /* 390 * __hfs_iget() 391 * 392 * Given the MDB for a HFS filesystem, a 'key' and an 'entry' in 393 * the catalog B-tree and the 'type' of the desired file return the 394 * inode for that file/directory or NULL. Note that 'type' indicates 395 * whether we want the actual file or directory, or the corresponding 396 * metadata (AppleDouble header file or CAP metadata file). 397 */ 398 struct inode *hfs_iget(struct super_block *sb, struct hfs_cat_key *key, hfs_cat_rec *rec) 399 { 400 struct hfs_iget_data data = { key, rec }; 401 struct inode *inode; 402 u32 cnid; 403 404 switch (rec->type) { 405 case HFS_CDR_DIR: 406 cnid = be32_to_cpu(rec->dir.DirID); 407 break; 408 case HFS_CDR_FIL: 409 cnid = be32_to_cpu(rec->file.FlNum); 410 break; 411 default: 412 return NULL; 413 } 414 inode = iget5_locked(sb, cnid, hfs_test_inode, hfs_read_inode, &data); 415 if (inode && (inode->i_state & I_NEW)) 416 unlock_new_inode(inode); 417 return inode; 418 } 419 420 void hfs_inode_write_fork(struct inode *inode, struct hfs_extent *ext, 421 __be32 *log_size, __be32 *phys_size) 422 { 423 memcpy(ext, HFS_I(inode)->first_extents, sizeof(hfs_extent_rec)); 424 425 if (log_size) 426 *log_size = cpu_to_be32(inode->i_size); 427 if (phys_size) 428 *phys_size = cpu_to_be32(HFS_I(inode)->alloc_blocks * 429 HFS_SB(inode->i_sb)->alloc_blksz); 430 } 431 432 int hfs_write_inode(struct inode *inode, struct writeback_control *wbc) 433 { 434 struct inode *main_inode = inode; 435 struct hfs_find_data fd; 436 hfs_cat_rec rec; 437 int res; 438 439 hfs_dbg("ino %lu\n", inode->i_ino); 440 res = hfs_ext_write_extent(inode); 441 if (res) 442 return res; 443 444 if (inode->i_ino < HFS_FIRSTUSER_CNID) { 445 switch (inode->i_ino) { 446 case HFS_ROOT_CNID: 447 break; 448 case HFS_EXT_CNID: 449 hfs_btree_write(HFS_SB(inode->i_sb)->ext_tree); 450 return 0; 451 case HFS_CAT_CNID: 452 hfs_btree_write(HFS_SB(inode->i_sb)->cat_tree); 453 return 0; 454 default: 455 BUG(); 456 return -EIO; 457 } 458 } 459 460 if (HFS_IS_RSRC(inode)) 461 main_inode = HFS_I(inode)->rsrc_inode; 462 463 if (!main_inode->i_nlink) 464 return 0; 465 466 if (hfs_find_init(HFS_SB(main_inode->i_sb)->cat_tree, &fd)) 467 /* panic? */ 468 return -EIO; 469 470 res = -EIO; 471 if (HFS_I(main_inode)->cat_key.CName.len > HFS_NAMELEN) 472 goto out; 473 fd.search_key->cat = HFS_I(main_inode)->cat_key; 474 if (hfs_brec_find(&fd)) 475 goto out; 476 477 if (S_ISDIR(main_inode->i_mode)) { 478 if (fd.entrylength < sizeof(struct hfs_cat_dir)) 479 goto out; 480 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, 481 sizeof(struct hfs_cat_dir)); 482 if (rec.type != HFS_CDR_DIR || 483 be32_to_cpu(rec.dir.DirID) != inode->i_ino) { 484 } 485 486 rec.dir.MdDat = hfs_u_to_mtime(inode_get_mtime(inode)); 487 rec.dir.Val = cpu_to_be16(inode->i_size - 2); 488 489 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset, 490 sizeof(struct hfs_cat_dir)); 491 } else if (HFS_IS_RSRC(inode)) { 492 if (fd.entrylength < sizeof(struct hfs_cat_file)) 493 goto out; 494 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, 495 sizeof(struct hfs_cat_file)); 496 hfs_inode_write_fork(inode, rec.file.RExtRec, 497 &rec.file.RLgLen, &rec.file.RPyLen); 498 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset, 499 sizeof(struct hfs_cat_file)); 500 } else { 501 if (fd.entrylength < sizeof(struct hfs_cat_file)) 502 goto out; 503 hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, 504 sizeof(struct hfs_cat_file)); 505 if (rec.type != HFS_CDR_FIL || 506 be32_to_cpu(rec.file.FlNum) != inode->i_ino) { 507 } 508 509 if (inode->i_mode & S_IWUSR) 510 rec.file.Flags &= ~HFS_FIL_LOCK; 511 else 512 rec.file.Flags |= HFS_FIL_LOCK; 513 hfs_inode_write_fork(inode, rec.file.ExtRec, &rec.file.LgLen, &rec.file.PyLen); 514 rec.file.MdDat = hfs_u_to_mtime(inode_get_mtime(inode)); 515 516 hfs_bnode_write(fd.bnode, &rec, fd.entryoffset, 517 sizeof(struct hfs_cat_file)); 518 } 519 res = 0; 520 out: 521 hfs_find_exit(&fd); 522 return res; 523 } 524 525 static struct dentry *hfs_file_lookup(struct inode *dir, struct dentry *dentry, 526 unsigned int flags) 527 { 528 struct inode *inode = NULL; 529 hfs_cat_rec rec; 530 struct hfs_find_data fd; 531 int res; 532 533 if (HFS_IS_RSRC(dir) || strcmp(dentry->d_name.name, "rsrc")) 534 goto out; 535 536 inode = HFS_I(dir)->rsrc_inode; 537 if (inode) 538 goto out; 539 540 inode = new_inode(dir->i_sb); 541 if (!inode) 542 return ERR_PTR(-ENOMEM); 543 544 res = hfs_find_init(HFS_SB(dir->i_sb)->cat_tree, &fd); 545 if (res) { 546 iput(inode); 547 return ERR_PTR(res); 548 } 549 fd.search_key->cat = HFS_I(dir)->cat_key; 550 res = hfs_brec_read(&fd, &rec, sizeof(rec)); 551 if (!res) { 552 struct hfs_iget_data idata = { NULL, &rec }; 553 hfs_read_inode(inode, &idata); 554 } 555 hfs_find_exit(&fd); 556 if (res) { 557 iput(inode); 558 return ERR_PTR(res); 559 } 560 HFS_I(inode)->rsrc_inode = dir; 561 HFS_I(dir)->rsrc_inode = inode; 562 igrab(dir); 563 inode_fake_hash(inode); 564 mark_inode_dirty(inode); 565 dont_mount(dentry); 566 out: 567 return d_splice_alias(inode, dentry); 568 } 569 570 void hfs_evict_inode(struct inode *inode) 571 { 572 truncate_inode_pages_final(&inode->i_data); 573 clear_inode(inode); 574 if (HFS_IS_RSRC(inode) && HFS_I(inode)->rsrc_inode) { 575 HFS_I(HFS_I(inode)->rsrc_inode)->rsrc_inode = NULL; 576 iput(HFS_I(inode)->rsrc_inode); 577 } 578 } 579 580 static int hfs_file_open(struct inode *inode, struct file *file) 581 { 582 if (HFS_IS_RSRC(inode)) 583 inode = HFS_I(inode)->rsrc_inode; 584 atomic_inc(&HFS_I(inode)->opencnt); 585 return 0; 586 } 587 588 static int hfs_file_release(struct inode *inode, struct file *file) 589 { 590 //struct super_block *sb = inode->i_sb; 591 592 if (HFS_IS_RSRC(inode)) 593 inode = HFS_I(inode)->rsrc_inode; 594 if (atomic_dec_and_test(&HFS_I(inode)->opencnt)) { 595 inode_lock(inode); 596 hfs_file_truncate(inode); 597 //if (inode->i_flags & S_DEAD) { 598 // hfs_delete_cat(inode->i_ino, HFSPLUS_SB(sb).hidden_dir, NULL); 599 // hfs_delete_inode(inode); 600 //} 601 inode_unlock(inode); 602 } 603 return 0; 604 } 605 606 /* 607 * hfs_notify_change() 608 * 609 * Based very closely on fs/msdos/inode.c by Werner Almesberger 610 * 611 * This is the notify_change() field in the super_operations structure 612 * for HFS file systems. The purpose is to take that changes made to 613 * an inode and apply then in a filesystem-dependent manner. In this 614 * case the process has a few of tasks to do: 615 * 1) prevent changes to the i_uid and i_gid fields. 616 * 2) map file permissions to the closest allowable permissions 617 * 3) Since multiple Linux files can share the same on-disk inode under 618 * HFS (for instance the data and resource forks of a file) a change 619 * to permissions must be applied to all other in-core inodes which 620 * correspond to the same HFS file. 621 */ 622 623 int hfs_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry, 624 struct iattr *attr) 625 { 626 struct inode *inode = d_inode(dentry); 627 struct hfs_sb_info *hsb = HFS_SB(inode->i_sb); 628 int error; 629 630 error = setattr_prepare(&nop_mnt_idmap, dentry, 631 attr); /* basic permission checks */ 632 if (error) 633 return error; 634 635 /* no uig/gid changes and limit which mode bits can be set */ 636 if (((attr->ia_valid & ATTR_UID) && 637 (!uid_eq(attr->ia_uid, hsb->s_uid))) || 638 ((attr->ia_valid & ATTR_GID) && 639 (!gid_eq(attr->ia_gid, hsb->s_gid))) || 640 ((attr->ia_valid & ATTR_MODE) && 641 ((S_ISDIR(inode->i_mode) && 642 (attr->ia_mode != inode->i_mode)) || 643 (attr->ia_mode & ~HFS_VALID_MODE_BITS)))) { 644 return hsb->s_quiet ? 0 : error; 645 } 646 647 if (attr->ia_valid & ATTR_MODE) { 648 /* Only the 'w' bits can ever change and only all together. */ 649 if (attr->ia_mode & S_IWUSR) 650 attr->ia_mode = inode->i_mode | S_IWUGO; 651 else 652 attr->ia_mode = inode->i_mode & ~S_IWUGO; 653 attr->ia_mode &= S_ISDIR(inode->i_mode) ? ~hsb->s_dir_umask: ~hsb->s_file_umask; 654 } 655 656 if ((attr->ia_valid & ATTR_SIZE) && 657 attr->ia_size != i_size_read(inode)) { 658 inode_dio_wait(inode); 659 660 error = inode_newsize_ok(inode, attr->ia_size); 661 if (error) 662 return error; 663 664 truncate_setsize(inode, attr->ia_size); 665 hfs_file_truncate(inode); 666 simple_inode_init_ts(inode); 667 } 668 669 setattr_copy(&nop_mnt_idmap, inode, attr); 670 mark_inode_dirty(inode); 671 return 0; 672 } 673 674 static int hfs_file_fsync(struct file *filp, loff_t start, loff_t end, 675 int datasync) 676 { 677 struct inode *inode = filp->f_mapping->host; 678 struct super_block * sb; 679 int ret, err; 680 681 ret = file_write_and_wait_range(filp, start, end); 682 if (ret) 683 return ret; 684 inode_lock(inode); 685 686 /* sync the inode to buffers */ 687 ret = write_inode_now(inode, 0); 688 689 /* sync the superblock to buffers */ 690 sb = inode->i_sb; 691 flush_delayed_work(&HFS_SB(sb)->mdb_work); 692 /* .. finally sync the buffers to disk */ 693 err = sync_blockdev(sb->s_bdev); 694 if (!ret) 695 ret = err; 696 inode_unlock(inode); 697 return ret; 698 } 699 700 static const struct file_operations hfs_file_operations = { 701 .llseek = generic_file_llseek, 702 .read_iter = generic_file_read_iter, 703 .write_iter = generic_file_write_iter, 704 .mmap_prepare = generic_file_mmap_prepare, 705 .splice_read = filemap_splice_read, 706 .splice_write = iter_file_splice_write, 707 .fsync = hfs_file_fsync, 708 .open = hfs_file_open, 709 .release = hfs_file_release, 710 }; 711 712 static const struct inode_operations hfs_file_inode_operations = { 713 .lookup = hfs_file_lookup, 714 .setattr = hfs_inode_setattr, 715 .listxattr = generic_listxattr, 716 }; 717