1/** 2 * dir.c - NTFS kernel directory operations. Part of the Linux-NTFS project. 3 * 4 * Copyright (c) 2001-2007 Anton Altaparmakov 5 * Copyright (c) 2002 Richard Russon 6 * 7 * This program/include file is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License as published 9 * by the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 * 12 * This program/include file is distributed in the hope that it will be 13 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty 14 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program (in the main directory of the Linux-NTFS 19 * distribution in the file COPYING); if not, write to the Free Software 20 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 21 */ 22 23#include <linux/buffer_head.h> 24#include <linux/slab.h> 25 26#include "dir.h" 27#include "aops.h" 28#include "attrib.h" 29#include "mft.h" 30#include "debug.h" 31#include "ntfs.h" 32 33/** 34 * The little endian Unicode string $I30 as a global constant. 35 */ 36ntfschar I30[5] = { cpu_to_le16('$'), cpu_to_le16('I'), 37 cpu_to_le16('3'), cpu_to_le16('0'), 0 }; 38 39/** 40 * ntfs_lookup_inode_by_name - find an inode in a directory given its name 41 * @dir_ni: ntfs inode of the directory in which to search for the name 42 * @uname: Unicode name for which to search in the directory 43 * @uname_len: length of the name @uname in Unicode characters 44 * @res: return the found file name if necessary (see below) 45 * 46 * Look for an inode with name @uname in the directory with inode @dir_ni. 47 * ntfs_lookup_inode_by_name() walks the contents of the directory looking for 48 * the Unicode name. If the name is found in the directory, the corresponding 49 * inode number (>= 0) is returned as a mft reference in cpu format, i.e. it 50 * is a 64-bit number containing the sequence number. 51 * 52 * On error, a negative value is returned corresponding to the error code. In 53 * particular if the inode is not found -ENOENT is returned. Note that you 54 * can't just check the return value for being negative, you have to check the 55 * inode number for being negative which you can extract using MREC(return 56 * value). 57 * 58 * Note, @uname_len does not include the (optional) terminating NULL character. 59 * 60 * Note, we look for a case sensitive match first but we also look for a case 61 * insensitive match at the same time. If we find a case insensitive match, we 62 * save that for the case that we don't find an exact match, where we return 63 * the case insensitive match and setup @res (which we allocate!) with the mft 64 * reference, the file name type, length and with a copy of the little endian 65 * Unicode file name itself. If we match a file name which is in the DOS name 66 * space, we only return the mft reference and file name type in @res. 67 * ntfs_lookup() then uses this to find the long file name in the inode itself. 68 * This is to avoid polluting the dcache with short file names. We want them to 69 * work but we don't care for how quickly one can access them. This also fixes 70 * the dcache aliasing issues. 71 * 72 * Locking: - Caller must hold i_mutex on the directory. 73 * - Each page cache page in the index allocation mapping must be 74 * locked whilst being accessed otherwise we may find a corrupt 75 * page due to it being under ->writepage at the moment which 76 * applies the mst protection fixups before writing out and then 77 * removes them again after the write is complete after which it 78 * unlocks the page. 79 */ 80MFT_REF ntfs_lookup_inode_by_name(ntfs_inode *dir_ni, const ntfschar *uname, 81 const int uname_len, ntfs_name **res) 82{ 83 ntfs_volume *vol = dir_ni->vol; 84 struct super_block *sb = vol->sb; 85 MFT_RECORD *m; 86 INDEX_ROOT *ir; 87 INDEX_ENTRY *ie; 88 INDEX_ALLOCATION *ia; 89 u8 *index_end; 90 u64 mref; 91 ntfs_attr_search_ctx *ctx; 92 int err, rc; 93 VCN vcn, old_vcn; 94 struct address_space *ia_mapping; 95 struct page *page; 96 u8 *kaddr; 97 ntfs_name *name = NULL; 98 99 BUG_ON(!S_ISDIR(VFS_I(dir_ni)->i_mode)); 100 BUG_ON(NInoAttr(dir_ni)); 101 /* Get hold of the mft record for the directory. */ 102 m = map_mft_record(dir_ni); 103 if (IS_ERR(m)) { 104 ntfs_error(sb, "map_mft_record() failed with error code %ld.", 105 -PTR_ERR(m)); 106 return ERR_MREF(PTR_ERR(m)); 107 } 108 ctx = ntfs_attr_get_search_ctx(dir_ni, m); 109 if (unlikely(!ctx)) { 110 err = -ENOMEM; 111 goto err_out; 112 } 113 /* Find the index root attribute in the mft record. */ 114 err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE, 0, NULL, 115 0, ctx); 116 if (unlikely(err)) { 117 if (err == -ENOENT) { 118 ntfs_error(sb, "Index root attribute missing in " 119 "directory inode 0x%lx.", 120 dir_ni->mft_no); 121 err = -EIO; 122 } 123 goto err_out; 124 } 125 /* Get to the index root value (it's been verified in read_inode). */ 126 ir = (INDEX_ROOT*)((u8*)ctx->attr + 127 le16_to_cpu(ctx->attr->data.resident.value_offset)); 128 index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length); 129 /* The first index entry. */ 130 ie = (INDEX_ENTRY*)((u8*)&ir->index + 131 le32_to_cpu(ir->index.entries_offset)); 132 /* 133 * Loop until we exceed valid memory (corruption case) or until we 134 * reach the last entry. 135 */ 136 for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) { 137 /* Bounds checks. */ 138 if ((u8*)ie < (u8*)ctx->mrec || (u8*)ie + 139 sizeof(INDEX_ENTRY_HEADER) > index_end || 140 (u8*)ie + le16_to_cpu(ie->key_length) > 141 index_end) 142 goto dir_err_out; 143 /* 144 * The last entry cannot contain a name. It can however contain 145 * a pointer to a child node in the B+tree so we just break out. 146 */ 147 if (ie->flags & INDEX_ENTRY_END) 148 break; 149 /* 150 * We perform a case sensitive comparison and if that matches 151 * we are done and return the mft reference of the inode (i.e. 152 * the inode number together with the sequence number for 153 * consistency checking). We convert it to cpu format before 154 * returning. 155 */ 156 if (ntfs_are_names_equal(uname, uname_len, 157 (ntfschar*)&ie->key.file_name.file_name, 158 ie->key.file_name.file_name_length, 159 CASE_SENSITIVE, vol->upcase, vol->upcase_len)) { 160found_it: 161 /* 162 * We have a perfect match, so we don't need to care 163 * about having matched imperfectly before, so we can 164 * free name and set *res to NULL. 165 * However, if the perfect match is a short file name, 166 * we need to signal this through *res, so that 167 * ntfs_lookup() can fix dcache aliasing issues. 168 * As an optimization we just reuse an existing 169 * allocation of *res. 170 */ 171 if (ie->key.file_name.file_name_type == FILE_NAME_DOS) { 172 if (!name) { 173 name = kmalloc(sizeof(ntfs_name), 174 GFP_NOFS); 175 if (!name) { 176 err = -ENOMEM; 177 goto err_out; 178 } 179 } 180 name->mref = le64_to_cpu( 181 ie->data.dir.indexed_file); 182 name->type = FILE_NAME_DOS; 183 name->len = 0; 184 *res = name; 185 } else { 186 kfree(name); 187 *res = NULL; 188 } 189 mref = le64_to_cpu(ie->data.dir.indexed_file); 190 ntfs_attr_put_search_ctx(ctx); 191 unmap_mft_record(dir_ni); 192 return mref; 193 } 194 /* 195 * For a case insensitive mount, we also perform a case 196 * insensitive comparison (provided the file name is not in the 197 * POSIX namespace). If the comparison matches, and the name is 198 * in the WIN32 namespace, we cache the filename in *res so 199 * that the caller, ntfs_lookup(), can work on it. If the 200 * comparison matches, and the name is in the DOS namespace, we 201 * only cache the mft reference and the file name type (we set 202 * the name length to zero for simplicity). 203 */ 204 if (!NVolCaseSensitive(vol) && 205 ie->key.file_name.file_name_type && 206 ntfs_are_names_equal(uname, uname_len, 207 (ntfschar*)&ie->key.file_name.file_name, 208 ie->key.file_name.file_name_length, 209 IGNORE_CASE, vol->upcase, vol->upcase_len)) { 210 int name_size = sizeof(ntfs_name); 211 u8 type = ie->key.file_name.file_name_type; 212 u8 len = ie->key.file_name.file_name_length; 213 214 /* Only one case insensitive matching name allowed. */ 215 if (name) { 216 ntfs_error(sb, "Found already allocated name " 217 "in phase 1. Please run chkdsk " 218 "and if that doesn't find any " 219 "errors please report you saw " 220 "this message to " 221 "linux-ntfs-dev@lists." 222 "sourceforge.net."); 223 goto dir_err_out; 224 } 225 226 if (type != FILE_NAME_DOS) 227 name_size += len * sizeof(ntfschar); 228 name = kmalloc(name_size, GFP_NOFS); 229 if (!name) { 230 err = -ENOMEM; 231 goto err_out; 232 } 233 name->mref = le64_to_cpu(ie->data.dir.indexed_file); 234 name->type = type; 235 if (type != FILE_NAME_DOS) { 236 name->len = len; 237 memcpy(name->name, ie->key.file_name.file_name, 238 len * sizeof(ntfschar)); 239 } else 240 name->len = 0; 241 *res = name; 242 } 243 /* 244 * Not a perfect match, need to do full blown collation so we 245 * know which way in the B+tree we have to go. 246 */ 247 rc = ntfs_collate_names(uname, uname_len, 248 (ntfschar*)&ie->key.file_name.file_name, 249 ie->key.file_name.file_name_length, 1, 250 IGNORE_CASE, vol->upcase, vol->upcase_len); 251 /* 252 * If uname collates before the name of the current entry, there 253 * is definitely no such name in this index but we might need to 254 * descend into the B+tree so we just break out of the loop. 255 */ 256 if (rc == -1) 257 break; 258 /* The names are not equal, continue the search. */ 259 if (rc) 260 continue; 261 /* 262 * Names match with case insensitive comparison, now try the 263 * case sensitive comparison, which is required for proper 264 * collation. 265 */ 266 rc = ntfs_collate_names(uname, uname_len, 267 (ntfschar*)&ie->key.file_name.file_name, 268 ie->key.file_name.file_name_length, 1, 269 CASE_SENSITIVE, vol->upcase, vol->upcase_len); 270 if (rc == -1) 271 break; 272 if (rc) 273 continue; 274 /* 275 * Perfect match, this will never happen as the 276 * ntfs_are_names_equal() call will have gotten a match but we 277 * still treat it correctly. 278 */ 279 goto found_it; 280 } 281 /* 282 * We have finished with this index without success. Check for the 283 * presence of a child node and if not present return -ENOENT, unless 284 * we have got a matching name cached in name in which case return the 285 * mft reference associated with it. 286 */ 287 if (!(ie->flags & INDEX_ENTRY_NODE)) { 288 if (name) { 289 ntfs_attr_put_search_ctx(ctx); 290 unmap_mft_record(dir_ni); 291 return name->mref; 292 } 293 ntfs_debug("Entry not found."); 294 err = -ENOENT; 295 goto err_out; 296 } /* Child node present, descend into it. */ 297 /* Consistency check: Verify that an index allocation exists. */ 298 if (!NInoIndexAllocPresent(dir_ni)) { 299 ntfs_error(sb, "No index allocation attribute but index entry " 300 "requires one. Directory inode 0x%lx is " 301 "corrupt or driver bug.", dir_ni->mft_no); 302 goto err_out; 303 } 304 /* Get the starting vcn of the index_block holding the child node. */ 305 vcn = sle64_to_cpup((sle64*)((u8*)ie + le16_to_cpu(ie->length) - 8)); 306 ia_mapping = VFS_I(dir_ni)->i_mapping; 307 /* 308 * We are done with the index root and the mft record. Release them, 309 * otherwise we deadlock with ntfs_map_page(). 310 */ 311 ntfs_attr_put_search_ctx(ctx); 312 unmap_mft_record(dir_ni); 313 m = NULL; 314 ctx = NULL; 315descend_into_child_node: 316 /* 317 * Convert vcn to index into the index allocation attribute in units 318 * of PAGE_CACHE_SIZE and map the page cache page, reading it from 319 * disk if necessary. 320 */ 321 page = ntfs_map_page(ia_mapping, vcn << 322 dir_ni->itype.index.vcn_size_bits >> PAGE_CACHE_SHIFT); 323 if (IS_ERR(page)) { 324 ntfs_error(sb, "Failed to map directory index page, error %ld.", 325 -PTR_ERR(page)); 326 err = PTR_ERR(page); 327 goto err_out; 328 } 329 lock_page(page); 330 kaddr = (u8*)page_address(page); 331fast_descend_into_child_node: 332 /* Get to the index allocation block. */ 333 ia = (INDEX_ALLOCATION*)(kaddr + ((vcn << 334 dir_ni->itype.index.vcn_size_bits) & ~PAGE_CACHE_MASK)); 335 /* Bounds checks. */ 336 if ((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_CACHE_SIZE) { 337 ntfs_error(sb, "Out of bounds check failed. Corrupt directory " 338 "inode 0x%lx or driver bug.", dir_ni->mft_no); 339 goto unm_err_out; 340 } 341 /* Catch multi sector transfer fixup errors. */ 342 if (unlikely(!ntfs_is_indx_record(ia->magic))) { 343 ntfs_error(sb, "Directory index record with vcn 0x%llx is " 344 "corrupt. Corrupt inode 0x%lx. Run chkdsk.", 345 (unsigned long long)vcn, dir_ni->mft_no); 346 goto unm_err_out; 347 } 348 if (sle64_to_cpu(ia->index_block_vcn) != vcn) { 349 ntfs_error(sb, "Actual VCN (0x%llx) of index buffer is " 350 "different from expected VCN (0x%llx). " 351 "Directory inode 0x%lx is corrupt or driver " 352 "bug.", (unsigned long long) 353 sle64_to_cpu(ia->index_block_vcn), 354 (unsigned long long)vcn, dir_ni->mft_no); 355 goto unm_err_out; 356 } 357 if (le32_to_cpu(ia->index.allocated_size) + 0x18 != 358 dir_ni->itype.index.block_size) { 359 ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode " 360 "0x%lx has a size (%u) differing from the " 361 "directory specified size (%u). Directory " 362 "inode is corrupt or driver bug.", 363 (unsigned long long)vcn, dir_ni->mft_no, 364 le32_to_cpu(ia->index.allocated_size) + 0x18, 365 dir_ni->itype.index.block_size); 366 goto unm_err_out; 367 } 368 index_end = (u8*)ia + dir_ni->itype.index.block_size; 369 if (index_end > kaddr + PAGE_CACHE_SIZE) { 370 ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode " 371 "0x%lx crosses page boundary. Impossible! " 372 "Cannot access! This is probably a bug in the " 373 "driver.", (unsigned long long)vcn, 374 dir_ni->mft_no); 375 goto unm_err_out; 376 } 377 index_end = (u8*)&ia->index + le32_to_cpu(ia->index.index_length); 378 if (index_end > (u8*)ia + dir_ni->itype.index.block_size) { 379 ntfs_error(sb, "Size of index buffer (VCN 0x%llx) of directory " 380 "inode 0x%lx exceeds maximum size.", 381 (unsigned long long)vcn, dir_ni->mft_no); 382 goto unm_err_out; 383 } 384 /* The first index entry. */ 385 ie = (INDEX_ENTRY*)((u8*)&ia->index + 386 le32_to_cpu(ia->index.entries_offset)); 387 /* 388 * Iterate similar to above big loop but applied to index buffer, thus 389 * loop until we exceed valid memory (corruption case) or until we 390 * reach the last entry. 391 */ 392 for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) { 393 /* Bounds check. */ 394 if ((u8*)ie < (u8*)ia || (u8*)ie + 395 sizeof(INDEX_ENTRY_HEADER) > index_end || 396 (u8*)ie + le16_to_cpu(ie->key_length) > 397 index_end) { 398 ntfs_error(sb, "Index entry out of bounds in " 399 "directory inode 0x%lx.", 400 dir_ni->mft_no); 401 goto unm_err_out; 402 } 403 /* 404 * The last entry cannot contain a name. It can however contain 405 * a pointer to a child node in the B+tree so we just break out. 406 */ 407 if (ie->flags & INDEX_ENTRY_END) 408 break; 409 /* 410 * We perform a case sensitive comparison and if that matches 411 * we are done and return the mft reference of the inode (i.e. 412 * the inode number together with the sequence number for 413 * consistency checking). We convert it to cpu format before 414 * returning. 415 */ 416 if (ntfs_are_names_equal(uname, uname_len, 417 (ntfschar*)&ie->key.file_name.file_name, 418 ie->key.file_name.file_name_length, 419 CASE_SENSITIVE, vol->upcase, vol->upcase_len)) { 420found_it2: 421 /* 422 * We have a perfect match, so we don't need to care 423 * about having matched imperfectly before, so we can 424 * free name and set *res to NULL. 425 * However, if the perfect match is a short file name, 426 * we need to signal this through *res, so that 427 * ntfs_lookup() can fix dcache aliasing issues. 428 * As an optimization we just reuse an existing 429 * allocation of *res. 430 */ 431 if (ie->key.file_name.file_name_type == FILE_NAME_DOS) { 432 if (!name) { 433 name = kmalloc(sizeof(ntfs_name), 434 GFP_NOFS); 435 if (!name) { 436 err = -ENOMEM; 437 goto unm_err_out; 438 } 439 } 440 name->mref = le64_to_cpu( 441 ie->data.dir.indexed_file); 442 name->type = FILE_NAME_DOS; 443 name->len = 0; 444 *res = name; 445 } else { 446 kfree(name); 447 *res = NULL; 448 } 449 mref = le64_to_cpu(ie->data.dir.indexed_file); 450 unlock_page(page); 451 ntfs_unmap_page(page); 452 return mref; 453 } 454 /* 455 * For a case insensitive mount, we also perform a case 456 * insensitive comparison (provided the file name is not in the 457 * POSIX namespace). If the comparison matches, and the name is 458 * in the WIN32 namespace, we cache the filename in *res so 459 * that the caller, ntfs_lookup(), can work on it. If the 460 * comparison matches, and the name is in the DOS namespace, we 461 * only cache the mft reference and the file name type (we set 462 * the name length to zero for simplicity). 463 */ 464 if (!NVolCaseSensitive(vol) && 465 ie->key.file_name.file_name_type && 466 ntfs_are_names_equal(uname, uname_len, 467 (ntfschar*)&ie->key.file_name.file_name, 468 ie->key.file_name.file_name_length, 469 IGNORE_CASE, vol->upcase, vol->upcase_len)) { 470 int name_size = sizeof(ntfs_name); 471 u8 type = ie->key.file_name.file_name_type; 472 u8 len = ie->key.file_name.file_name_length; 473 474 /* Only one case insensitive matching name allowed. */ 475 if (name) { 476 ntfs_error(sb, "Found already allocated name " 477 "in phase 2. Please run chkdsk " 478 "and if that doesn't find any " 479 "errors please report you saw " 480 "this message to " 481 "linux-ntfs-dev@lists." 482 "sourceforge.net."); 483 unlock_page(page); 484 ntfs_unmap_page(page); 485 goto dir_err_out; 486 } 487 488 if (type != FILE_NAME_DOS) 489 name_size += len * sizeof(ntfschar); 490 name = kmalloc(name_size, GFP_NOFS); 491 if (!name) { 492 err = -ENOMEM; 493 goto unm_err_out; 494 } 495 name->mref = le64_to_cpu(ie->data.dir.indexed_file); 496 name->type = type; 497 if (type != FILE_NAME_DOS) { 498 name->len = len; 499 memcpy(name->name, ie->key.file_name.file_name, 500 len * sizeof(ntfschar)); 501 } else 502 name->len = 0; 503 *res = name; 504 } 505 /* 506 * Not a perfect match, need to do full blown collation so we 507 * know which way in the B+tree we have to go. 508 */ 509 rc = ntfs_collate_names(uname, uname_len, 510 (ntfschar*)&ie->key.file_name.file_name, 511 ie->key.file_name.file_name_length, 1, 512 IGNORE_CASE, vol->upcase, vol->upcase_len); 513 /* 514 * If uname collates before the name of the current entry, there 515 * is definitely no such name in this index but we might need to 516 * descend into the B+tree so we just break out of the loop. 517 */ 518 if (rc == -1) 519 break; 520 /* The names are not equal, continue the search. */ 521 if (rc) 522 continue; 523 /* 524 * Names match with case insensitive comparison, now try the 525 * case sensitive comparison, which is required for proper 526 * collation. 527 */ 528 rc = ntfs_collate_names(uname, uname_len, 529 (ntfschar*)&ie->key.file_name.file_name, 530 ie->key.file_name.file_name_length, 1, 531 CASE_SENSITIVE, vol->upcase, vol->upcase_len); 532 if (rc == -1) 533 break; 534 if (rc) 535 continue; 536 /* 537 * Perfect match, this will never happen as the 538 * ntfs_are_names_equal() call will have gotten a match but we 539 * still treat it correctly. 540 */ 541 goto found_it2; 542 } 543 /* 544 * We have finished with this index buffer without success. Check for 545 * the presence of a child node. 546 */ 547 if (ie->flags & INDEX_ENTRY_NODE) { 548 if ((ia->index.flags & NODE_MASK) == LEAF_NODE) { 549 ntfs_error(sb, "Index entry with child node found in " 550 "a leaf node in directory inode 0x%lx.", 551 dir_ni->mft_no); 552 goto unm_err_out; 553 } 554 /* Child node present, descend into it. */ 555 old_vcn = vcn; 556 vcn = sle64_to_cpup((sle64*)((u8*)ie + 557 le16_to_cpu(ie->length) - 8)); 558 if (vcn >= 0) { 559 /* If vcn is in the same page cache page as old_vcn we 560 * recycle the mapped page. */ 561 if (old_vcn << vol->cluster_size_bits >> 562 PAGE_CACHE_SHIFT == vcn << 563 vol->cluster_size_bits >> 564 PAGE_CACHE_SHIFT) 565 goto fast_descend_into_child_node; 566 unlock_page(page); 567 ntfs_unmap_page(page); 568 goto descend_into_child_node; 569 } 570 ntfs_error(sb, "Negative child node vcn in directory inode " 571 "0x%lx.", dir_ni->mft_no); 572 goto unm_err_out; 573 } 574 /* 575 * No child node present, return -ENOENT, unless we have got a matching 576 * name cached in name in which case return the mft reference 577 * associated with it. 578 */ 579 if (name) { 580 unlock_page(page); 581 ntfs_unmap_page(page); 582 return name->mref; 583 } 584 ntfs_debug("Entry not found."); 585 err = -ENOENT; 586unm_err_out: 587 unlock_page(page); 588 ntfs_unmap_page(page); 589err_out: 590 if (!err) 591 err = -EIO; 592 if (ctx) 593 ntfs_attr_put_search_ctx(ctx); 594 if (m) 595 unmap_mft_record(dir_ni); 596 if (name) { 597 kfree(name); 598 *res = NULL; 599 } 600 return ERR_MREF(err); 601dir_err_out: 602 ntfs_error(sb, "Corrupt directory. Aborting lookup."); 603 goto err_out; 604} 605 606 607/** 608 * ntfs_filldir - ntfs specific filldir method 609 * @vol: current ntfs volume 610 * @fpos: position in the directory 611 * @ndir: ntfs inode of current directory 612 * @ia_page: page in which the index allocation buffer @ie is in resides 613 * @ie: current index entry 614 * @name: buffer to use for the converted name 615 * @dirent: vfs filldir callback context 616 * @filldir: vfs filldir callback 617 * 618 * Convert the Unicode @name to the loaded NLS and pass it to the @filldir 619 * callback. 620 * 621 * If @ia_page is not NULL it is the locked page containing the index 622 * allocation block containing the index entry @ie. 623 * 624 * Note, we drop (and then reacquire) the page lock on @ia_page across the 625 * @filldir() call otherwise we would deadlock with NFSd when it calls ->lookup 626 * since ntfs_lookup() will lock the same page. As an optimization, we do not 627 * retake the lock if we are returning a non-zero value as ntfs_readdir() 628 * would need to drop the lock immediately anyway. 629 */ 630static inline int ntfs_filldir(ntfs_volume *vol, loff_t fpos, 631 ntfs_inode *ndir, struct page *ia_page, INDEX_ENTRY *ie, 632 u8 *name, void *dirent, filldir_t filldir) 633{ 634 unsigned long mref; 635 int name_len, rc; 636 unsigned dt_type; 637 FILE_NAME_TYPE_FLAGS name_type; 638 639 name_type = ie->key.file_name.file_name_type; 640 if (name_type == FILE_NAME_DOS) { 641 ntfs_debug("Skipping DOS name space entry."); 642 return 0; 643 } 644 if (MREF_LE(ie->data.dir.indexed_file) == FILE_root) { 645 ntfs_debug("Skipping root directory self reference entry."); 646 return 0; 647 } 648 if (MREF_LE(ie->data.dir.indexed_file) < FILE_first_user && 649 !NVolShowSystemFiles(vol)) { 650 ntfs_debug("Skipping system file."); 651 return 0; 652 } 653 name_len = ntfs_ucstonls(vol, (ntfschar*)&ie->key.file_name.file_name, 654 ie->key.file_name.file_name_length, &name, 655 NTFS_MAX_NAME_LEN * NLS_MAX_CHARSET_SIZE + 1); 656 if (name_len <= 0) { 657 ntfs_warning(vol->sb, "Skipping unrepresentable inode 0x%llx.", 658 (long long)MREF_LE(ie->data.dir.indexed_file)); 659 return 0; 660 } 661 if (ie->key.file_name.file_attributes & 662 FILE_ATTR_DUP_FILE_NAME_INDEX_PRESENT) 663 dt_type = DT_DIR; 664 else 665 dt_type = DT_REG; 666 mref = MREF_LE(ie->data.dir.indexed_file); 667 /* 668 * Drop the page lock otherwise we deadlock with NFS when it calls 669 * ->lookup since ntfs_lookup() will lock the same page. 670 */ 671 if (ia_page) 672 unlock_page(ia_page); 673 ntfs_debug("Calling filldir for %s with len %i, fpos 0x%llx, inode " 674 "0x%lx, DT_%s.", name, name_len, fpos, mref, 675 dt_type == DT_DIR ? "DIR" : "REG"); 676 rc = filldir(dirent, name, name_len, fpos, mref, dt_type); 677 /* Relock the page but not if we are aborting ->readdir. */ 678 if (!rc && ia_page) 679 lock_page(ia_page); 680 return rc; 681} 682 683/* 684 * We use the same basic approach as the old NTFS driver, i.e. we parse the 685 * index root entries and then the index allocation entries that are marked 686 * as in use in the index bitmap. 687 * 688 * While this will return the names in random order this doesn't matter for 689 * ->readdir but OTOH results in a faster ->readdir. 690 * 691 * VFS calls ->readdir without BKL but with i_mutex held. This protects the VFS 692 * parts (e.g. ->f_pos and ->i_size, and it also protects against directory 693 * modifications). 694 * 695 * Locking: - Caller must hold i_mutex on the directory. 696 * - Each page cache page in the index allocation mapping must be 697 * locked whilst being accessed otherwise we may find a corrupt 698 * page due to it being under ->writepage at the moment which 699 * applies the mst protection fixups before writing out and then 700 * removes them again after the write is complete after which it 701 * unlocks the page. 702 */ 703static int ntfs_readdir(struct file *filp, void *dirent, filldir_t filldir) 704{ 705 s64 ia_pos, ia_start, prev_ia_pos, bmp_pos; 706 loff_t fpos, i_size; 707 struct inode *bmp_vi, *vdir = filp->f_path.dentry->d_inode; 708 struct super_block *sb = vdir->i_sb; 709 ntfs_inode *ndir = NTFS_I(vdir); 710 ntfs_volume *vol = NTFS_SB(sb); 711 MFT_RECORD *m; 712 INDEX_ROOT *ir = NULL; 713 INDEX_ENTRY *ie; 714 INDEX_ALLOCATION *ia; 715 u8 *name = NULL; 716 int rc, err, ir_pos, cur_bmp_pos; 717 struct address_space *ia_mapping, *bmp_mapping; 718 struct page *bmp_page = NULL, *ia_page = NULL; 719 u8 *kaddr, *bmp, *index_end; 720 ntfs_attr_search_ctx *ctx; 721 722 fpos = filp->f_pos; 723 ntfs_debug("Entering for inode 0x%lx, fpos 0x%llx.", 724 vdir->i_ino, fpos); 725 rc = err = 0; 726 /* Are we at end of dir yet? */ 727 i_size = i_size_read(vdir); 728 if (fpos >= i_size + vol->mft_record_size) 729 goto done; 730 /* Emulate . and .. for all directories. */ 731 if (!fpos) { 732 ntfs_debug("Calling filldir for . with len 1, fpos 0x0, " 733 "inode 0x%lx, DT_DIR.", vdir->i_ino); 734 rc = filldir(dirent, ".", 1, fpos, vdir->i_ino, DT_DIR); 735 if (rc) 736 goto done; 737 fpos++; 738 } 739 if (fpos == 1) { 740 ntfs_debug("Calling filldir for .. with len 2, fpos 0x1, " 741 "inode 0x%lx, DT_DIR.", 742 (unsigned long)parent_ino(filp->f_path.dentry)); 743 rc = filldir(dirent, "..", 2, fpos, 744 parent_ino(filp->f_path.dentry), DT_DIR); 745 if (rc) 746 goto done; 747 fpos++; 748 } 749 m = NULL; 750 ctx = NULL; 751 /* 752 * Allocate a buffer to store the current name being processed 753 * converted to format determined by current NLS. 754 */ 755 name = kmalloc(NTFS_MAX_NAME_LEN * NLS_MAX_CHARSET_SIZE + 1, GFP_NOFS); 756 if (unlikely(!name)) { 757 err = -ENOMEM; 758 goto err_out; 759 } 760 /* Are we jumping straight into the index allocation attribute? */ 761 if (fpos >= vol->mft_record_size) 762 goto skip_index_root; 763 /* Get hold of the mft record for the directory. */ 764 m = map_mft_record(ndir); 765 if (IS_ERR(m)) { 766 err = PTR_ERR(m); 767 m = NULL; 768 goto err_out; 769 } 770 ctx = ntfs_attr_get_search_ctx(ndir, m); 771 if (unlikely(!ctx)) { 772 err = -ENOMEM; 773 goto err_out; 774 } 775 /* Get the offset into the index root attribute. */ 776 ir_pos = (s64)fpos; 777 /* Find the index root attribute in the mft record. */ 778 err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE, 0, NULL, 779 0, ctx); 780 if (unlikely(err)) { 781 ntfs_error(sb, "Index root attribute missing in directory " 782 "inode 0x%lx.", vdir->i_ino); 783 goto err_out; 784 } 785 /* 786 * Copy the index root attribute value to a buffer so that we can put 787 * the search context and unmap the mft record before calling the 788 * filldir() callback. We need to do this because of NFSd which calls 789 * ->lookup() from its filldir callback() and this causes NTFS to 790 * deadlock as ntfs_lookup() maps the mft record of the directory and 791 * we have got it mapped here already. The only solution is for us to 792 * unmap the mft record here so that a call to ntfs_lookup() is able to 793 * map the mft record without deadlocking. 794 */ 795 rc = le32_to_cpu(ctx->attr->data.resident.value_length); 796 ir = kmalloc(rc, GFP_NOFS); 797 if (unlikely(!ir)) { 798 err = -ENOMEM; 799 goto err_out; 800 } 801 /* Copy the index root value (it has been verified in read_inode). */ 802 memcpy(ir, (u8*)ctx->attr + 803 le16_to_cpu(ctx->attr->data.resident.value_offset), rc); 804 ntfs_attr_put_search_ctx(ctx); 805 unmap_mft_record(ndir); 806 ctx = NULL; 807 m = NULL; 808 index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length); 809 /* The first index entry. */ 810 ie = (INDEX_ENTRY*)((u8*)&ir->index + 811 le32_to_cpu(ir->index.entries_offset)); 812 /* 813 * Loop until we exceed valid memory (corruption case) or until we 814 * reach the last entry or until filldir tells us it has had enough 815 * or signals an error (both covered by the rc test). 816 */ 817 for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) { 818 ntfs_debug("In index root, offset 0x%zx.", (u8*)ie - (u8*)ir); 819 /* Bounds checks. */ 820 if (unlikely((u8*)ie < (u8*)ir || (u8*)ie + 821 sizeof(INDEX_ENTRY_HEADER) > index_end || 822 (u8*)ie + le16_to_cpu(ie->key_length) > 823 index_end)) 824 goto err_out; 825 /* The last entry cannot contain a name. */ 826 if (ie->flags & INDEX_ENTRY_END) 827 break; 828 /* Skip index root entry if continuing previous readdir. */ 829 if (ir_pos > (u8*)ie - (u8*)ir) 830 continue; 831 /* Advance the position even if going to skip the entry. */ 832 fpos = (u8*)ie - (u8*)ir; 833 /* Submit the name to the filldir callback. */ 834 rc = ntfs_filldir(vol, fpos, ndir, NULL, ie, name, dirent, 835 filldir); 836 if (rc) { 837 kfree(ir); 838 goto abort; 839 } 840 } 841 /* We are done with the index root and can free the buffer. */ 842 kfree(ir); 843 ir = NULL; 844 /* If there is no index allocation attribute we are finished. */ 845 if (!NInoIndexAllocPresent(ndir)) 846 goto EOD; 847 /* Advance fpos to the beginning of the index allocation. */ 848 fpos = vol->mft_record_size; 849skip_index_root: 850 kaddr = NULL; 851 prev_ia_pos = -1LL; 852 /* Get the offset into the index allocation attribute. */ 853 ia_pos = (s64)fpos - vol->mft_record_size; 854 ia_mapping = vdir->i_mapping; 855 ntfs_debug("Inode 0x%lx, getting index bitmap.", vdir->i_ino); 856 bmp_vi = ntfs_attr_iget(vdir, AT_BITMAP, I30, 4); 857 if (IS_ERR(bmp_vi)) { 858 ntfs_error(sb, "Failed to get bitmap attribute."); 859 err = PTR_ERR(bmp_vi); 860 goto err_out; 861 } 862 bmp_mapping = bmp_vi->i_mapping; 863 /* Get the starting bitmap bit position and sanity check it. */ 864 bmp_pos = ia_pos >> ndir->itype.index.block_size_bits; 865 if (unlikely(bmp_pos >> 3 >= i_size_read(bmp_vi))) { 866 ntfs_error(sb, "Current index allocation position exceeds " 867 "index bitmap size."); 868 goto iput_err_out; 869 } 870 /* Get the starting bit position in the current bitmap page. */ 871 cur_bmp_pos = bmp_pos & ((PAGE_CACHE_SIZE * 8) - 1); 872 bmp_pos &= ~(u64)((PAGE_CACHE_SIZE * 8) - 1); 873get_next_bmp_page: 874 ntfs_debug("Reading bitmap with page index 0x%llx, bit ofs 0x%llx", 875 (unsigned long long)bmp_pos >> (3 + PAGE_CACHE_SHIFT), 876 (unsigned long long)bmp_pos & 877 (unsigned long long)((PAGE_CACHE_SIZE * 8) - 1)); 878 bmp_page = ntfs_map_page(bmp_mapping, 879 bmp_pos >> (3 + PAGE_CACHE_SHIFT)); 880 if (IS_ERR(bmp_page)) { 881 ntfs_error(sb, "Reading index bitmap failed."); 882 err = PTR_ERR(bmp_page); 883 bmp_page = NULL; 884 goto iput_err_out; 885 } 886 bmp = (u8*)page_address(bmp_page); 887 /* Find next index block in use. */ 888 while (!(bmp[cur_bmp_pos >> 3] & (1 << (cur_bmp_pos & 7)))) { 889find_next_index_buffer: 890 cur_bmp_pos++; 891 /* 892 * If we have reached the end of the bitmap page, get the next 893 * page, and put away the old one. 894 */ 895 if (unlikely((cur_bmp_pos >> 3) >= PAGE_CACHE_SIZE)) { 896 ntfs_unmap_page(bmp_page); 897 bmp_pos += PAGE_CACHE_SIZE * 8; 898 cur_bmp_pos = 0; 899 goto get_next_bmp_page; 900 } 901 /* If we have reached the end of the bitmap, we are done. */ 902 if (unlikely(((bmp_pos + cur_bmp_pos) >> 3) >= i_size)) 903 goto unm_EOD; 904 ia_pos = (bmp_pos + cur_bmp_pos) << 905 ndir->itype.index.block_size_bits; 906 } 907 ntfs_debug("Handling index buffer 0x%llx.", 908 (unsigned long long)bmp_pos + cur_bmp_pos); 909 /* If the current index buffer is in the same page we reuse the page. */ 910 if ((prev_ia_pos & (s64)PAGE_CACHE_MASK) != 911 (ia_pos & (s64)PAGE_CACHE_MASK)) { 912 prev_ia_pos = ia_pos; 913 if (likely(ia_page != NULL)) { 914 unlock_page(ia_page); 915 ntfs_unmap_page(ia_page); 916 } 917 /* 918 * Map the page cache page containing the current ia_pos, 919 * reading it from disk if necessary. 920 */ 921 ia_page = ntfs_map_page(ia_mapping, ia_pos >> PAGE_CACHE_SHIFT); 922 if (IS_ERR(ia_page)) { 923 ntfs_error(sb, "Reading index allocation data failed."); 924 err = PTR_ERR(ia_page); 925 ia_page = NULL; 926 goto err_out; 927 } 928 lock_page(ia_page); 929 kaddr = (u8*)page_address(ia_page); 930 } 931 /* Get the current index buffer. */ 932 ia = (INDEX_ALLOCATION*)(kaddr + (ia_pos & ~PAGE_CACHE_MASK & 933 ~(s64)(ndir->itype.index.block_size - 1))); 934 /* Bounds checks. */ 935 if (unlikely((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_CACHE_SIZE)) { 936 ntfs_error(sb, "Out of bounds check failed. Corrupt directory " 937 "inode 0x%lx or driver bug.", vdir->i_ino); 938 goto err_out; 939 } 940 /* Catch multi sector transfer fixup errors. */ 941 if (unlikely(!ntfs_is_indx_record(ia->magic))) { 942 ntfs_error(sb, "Directory index record with vcn 0x%llx is " 943 "corrupt. Corrupt inode 0x%lx. Run chkdsk.", 944 (unsigned long long)ia_pos >> 945 ndir->itype.index.vcn_size_bits, vdir->i_ino); 946 goto err_out; 947 } 948 if (unlikely(sle64_to_cpu(ia->index_block_vcn) != (ia_pos & 949 ~(s64)(ndir->itype.index.block_size - 1)) >> 950 ndir->itype.index.vcn_size_bits)) { 951 ntfs_error(sb, "Actual VCN (0x%llx) of index buffer is " 952 "different from expected VCN (0x%llx). " 953 "Directory inode 0x%lx is corrupt or driver " 954 "bug. ", (unsigned long long) 955 sle64_to_cpu(ia->index_block_vcn), 956 (unsigned long long)ia_pos >> 957 ndir->itype.index.vcn_size_bits, vdir->i_ino); 958 goto err_out; 959 } 960 if (unlikely(le32_to_cpu(ia->index.allocated_size) + 0x18 != 961 ndir->itype.index.block_size)) { 962 ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode " 963 "0x%lx has a size (%u) differing from the " 964 "directory specified size (%u). Directory " 965 "inode is corrupt or driver bug.", 966 (unsigned long long)ia_pos >> 967 ndir->itype.index.vcn_size_bits, vdir->i_ino, 968 le32_to_cpu(ia->index.allocated_size) + 0x18, 969 ndir->itype.index.block_size); 970 goto err_out; 971 } 972 index_end = (u8*)ia + ndir->itype.index.block_size; 973 if (unlikely(index_end > kaddr + PAGE_CACHE_SIZE)) { 974 ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode " 975 "0x%lx crosses page boundary. Impossible! " 976 "Cannot access! This is probably a bug in the " 977 "driver.", (unsigned long long)ia_pos >> 978 ndir->itype.index.vcn_size_bits, vdir->i_ino); 979 goto err_out; 980 } 981 ia_start = ia_pos & ~(s64)(ndir->itype.index.block_size - 1); 982 index_end = (u8*)&ia->index + le32_to_cpu(ia->index.index_length); 983 if (unlikely(index_end > (u8*)ia + ndir->itype.index.block_size)) { 984 ntfs_error(sb, "Size of index buffer (VCN 0x%llx) of directory " 985 "inode 0x%lx exceeds maximum size.", 986 (unsigned long long)ia_pos >> 987 ndir->itype.index.vcn_size_bits, vdir->i_ino); 988 goto err_out; 989 } 990 /* The first index entry in this index buffer. */ 991 ie = (INDEX_ENTRY*)((u8*)&ia->index + 992 le32_to_cpu(ia->index.entries_offset)); 993 /* 994 * Loop until we exceed valid memory (corruption case) or until we 995 * reach the last entry or until filldir tells us it has had enough 996 * or signals an error (both covered by the rc test). 997 */ 998 for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) { 999 ntfs_debug("In index allocation, offset 0x%llx.", 1000 (unsigned long long)ia_start + 1001 (unsigned long long)((u8*)ie - (u8*)ia)); 1002 /* Bounds checks. */ 1003 if (unlikely((u8*)ie < (u8*)ia || (u8*)ie + 1004 sizeof(INDEX_ENTRY_HEADER) > index_end || 1005 (u8*)ie + le16_to_cpu(ie->key_length) > 1006 index_end)) 1007 goto err_out; 1008 /* The last entry cannot contain a name. */ 1009 if (ie->flags & INDEX_ENTRY_END) 1010 break; 1011 /* Skip index block entry if continuing previous readdir. */ 1012 if (ia_pos - ia_start > (u8*)ie - (u8*)ia) 1013 continue; 1014 /* Advance the position even if going to skip the entry. */ 1015 fpos = (u8*)ie - (u8*)ia + 1016 (sle64_to_cpu(ia->index_block_vcn) << 1017 ndir->itype.index.vcn_size_bits) + 1018 vol->mft_record_size; 1019 /* 1020 * Submit the name to the @filldir callback. Note, 1021 * ntfs_filldir() drops the lock on @ia_page but it retakes it 1022 * before returning, unless a non-zero value is returned in 1023 * which case the page is left unlocked. 1024 */ 1025 rc = ntfs_filldir(vol, fpos, ndir, ia_page, ie, name, dirent, 1026 filldir); 1027 if (rc) { 1028 /* @ia_page is already unlocked in this case. */ 1029 ntfs_unmap_page(ia_page); 1030 ntfs_unmap_page(bmp_page); 1031 iput(bmp_vi); 1032 goto abort; 1033 } 1034 } 1035 goto find_next_index_buffer; 1036unm_EOD: 1037 if (ia_page) { 1038 unlock_page(ia_page); 1039 ntfs_unmap_page(ia_page); 1040 } 1041 ntfs_unmap_page(bmp_page); 1042 iput(bmp_vi); 1043EOD: 1044 /* We are finished, set fpos to EOD. */ 1045 fpos = i_size + vol->mft_record_size; 1046abort: 1047 kfree(name); 1048done: 1049#ifdef DEBUG 1050 if (!rc) 1051 ntfs_debug("EOD, fpos 0x%llx, returning 0.", fpos); 1052 else 1053 ntfs_debug("filldir returned %i, fpos 0x%llx, returning 0.", 1054 rc, fpos); 1055#endif 1056 filp->f_pos = fpos; 1057 return 0; 1058err_out: 1059 if (bmp_page) { 1060 ntfs_unmap_page(bmp_page); 1061iput_err_out: 1062 iput(bmp_vi); 1063 } 1064 if (ia_page) { 1065 unlock_page(ia_page); 1066 ntfs_unmap_page(ia_page); 1067 } 1068 kfree(ir); 1069 kfree(name); 1070 if (ctx) 1071 ntfs_attr_put_search_ctx(ctx); 1072 if (m) 1073 unmap_mft_record(ndir); 1074 if (!err) 1075 err = -EIO; 1076 ntfs_debug("Failed. Returning error code %i.", -err); 1077 filp->f_pos = fpos; 1078 return err; 1079} 1080 1081/** 1082 * ntfs_dir_open - called when an inode is about to be opened 1083 * @vi: inode to be opened 1084 * @filp: file structure describing the inode 1085 * 1086 * Limit directory size to the page cache limit on architectures where unsigned 1087 * long is 32-bits. This is the most we can do for now without overflowing the 1088 * page cache page index. Doing it this way means we don't run into problems 1089 * because of existing too large directories. It would be better to allow the 1090 * user to read the accessible part of the directory but I doubt very much 1091 * anyone is going to hit this check on a 32-bit architecture, so there is no 1092 * point in adding the extra complexity required to support this. 1093 * 1094 * On 64-bit architectures, the check is hopefully optimized away by the 1095 * compiler. 1096 */ 1097static int ntfs_dir_open(struct inode *vi, struct file *filp) 1098{ 1099 if (sizeof(unsigned long) < 8) { 1100 if (i_size_read(vi) > MAX_LFS_FILESIZE) 1101 return -EFBIG; 1102 } 1103 return 0; 1104} 1105 1106#ifdef NTFS_RW 1107 1108/** 1109 * ntfs_dir_fsync - sync a directory to disk 1110 * @filp: directory to be synced 1111 * @dentry: dentry describing the directory to sync 1112 * @datasync: if non-zero only flush user data and not metadata 1113 * 1114 * Data integrity sync of a directory to disk. Used for fsync, fdatasync, and 1115 * msync system calls. This function is based on file.c::ntfs_file_fsync(). 1116 * 1117 * Write the mft record and all associated extent mft records as well as the 1118 * $INDEX_ALLOCATION and $BITMAP attributes and then sync the block device. 1119 * 1120 * If @datasync is true, we do not wait on the inode(s) to be written out 1121 * but we always wait on the page cache pages to be written out. 1122 * 1123 * Note: In the past @filp could be NULL so we ignore it as we don't need it 1124 * anyway. 1125 * 1126 * Locking: Caller must hold i_mutex on the inode. 1127 * 1128 * TODO: We should probably also write all attribute/index inodes associated 1129 * with this inode but since we have no simple way of getting to them we ignore 1130 * this problem for now. We do write the $BITMAP attribute if it is present 1131 * which is the important one for a directory so things are not too bad. 1132 */ 1133static int ntfs_dir_fsync(struct file *filp, int datasync) 1134{ 1135 struct inode *bmp_vi, *vi = filp->f_mapping->host; 1136 int err, ret; 1137 ntfs_attr na; 1138 1139 ntfs_debug("Entering for inode 0x%lx.", vi->i_ino); 1140 BUG_ON(!S_ISDIR(vi->i_mode)); 1141 /* If the bitmap attribute inode is in memory sync it, too. */ 1142 na.mft_no = vi->i_ino; 1143 na.type = AT_BITMAP; 1144 na.name = I30; 1145 na.name_len = 4; 1146 bmp_vi = ilookup5(vi->i_sb, vi->i_ino, (test_t)ntfs_test_inode, &na); 1147 if (bmp_vi) { 1148 write_inode_now(bmp_vi, !datasync); 1149 iput(bmp_vi); 1150 } 1151 ret = __ntfs_write_inode(vi, 1); 1152 write_inode_now(vi, !datasync); 1153 err = sync_blockdev(vi->i_sb->s_bdev); 1154 if (unlikely(err && !ret)) 1155 ret = err; 1156 if (likely(!ret)) 1157 ntfs_debug("Done."); 1158 else 1159 ntfs_warning(vi->i_sb, "Failed to f%ssync inode 0x%lx. Error " 1160 "%u.", datasync ? "data" : "", vi->i_ino, -ret); 1161 return ret; 1162} 1163 1164#endif /* NTFS_RW */ 1165 1166const struct file_operations ntfs_dir_ops = { 1167 .llseek = generic_file_llseek, /* Seek inside directory. */ 1168 .read = generic_read_dir, /* Return -EISDIR. */ 1169 .readdir = ntfs_readdir, /* Read directory contents. */ 1170#ifdef NTFS_RW 1171 .fsync = ntfs_dir_fsync, /* Sync a directory to disk. */ 1172 /*.aio_fsync = ,*/ /* Sync all outstanding async 1173 i/o operations on a kiocb. */ 1174#endif /* NTFS_RW */ 1175 /*.ioctl = ,*/ /* Perform function on the 1176 mounted filesystem. */ 1177 .open = ntfs_dir_open, /* Open directory. */ 1178}; 1179