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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/**
   3 * inode.c - NTFS kernel inode handling.
   4 *
   5 * Copyright (c) 2001-2014 Anton Altaparmakov and Tuxera Inc.
   6 */
   7
   8#include <linux/buffer_head.h>
   9#include <linux/fs.h>
  10#include <linux/mm.h>
  11#include <linux/mount.h>
  12#include <linux/mutex.h>
  13#include <linux/pagemap.h>
  14#include <linux/quotaops.h>
  15#include <linux/slab.h>
  16#include <linux/log2.h>
  17
  18#include "aops.h"
  19#include "attrib.h"
  20#include "bitmap.h"
  21#include "dir.h"
  22#include "debug.h"
  23#include "inode.h"
  24#include "lcnalloc.h"
  25#include "malloc.h"
  26#include "mft.h"
  27#include "time.h"
  28#include "ntfs.h"
  29
  30/**
  31 * ntfs_test_inode - compare two (possibly fake) inodes for equality
  32 * @vi:		vfs inode which to test
  33 * @data:	data which is being tested with
  34 *
  35 * Compare the ntfs attribute embedded in the ntfs specific part of the vfs
  36 * inode @vi for equality with the ntfs attribute @data.
  37 *
  38 * If searching for the normal file/directory inode, set @na->type to AT_UNUSED.
  39 * @na->name and @na->name_len are then ignored.
  40 *
  41 * Return 1 if the attributes match and 0 if not.
  42 *
  43 * NOTE: This function runs with the inode_hash_lock spin lock held so it is not
  44 * allowed to sleep.
  45 */
  46int ntfs_test_inode(struct inode *vi, void *data)
  47{
  48	ntfs_attr *na = (ntfs_attr *)data;
  49	ntfs_inode *ni;
  50
  51	if (vi->i_ino != na->mft_no)
  52		return 0;
  53	ni = NTFS_I(vi);
  54	/* If !NInoAttr(ni), @vi is a normal file or directory inode. */
  55	if (likely(!NInoAttr(ni))) {
  56		/* If not looking for a normal inode this is a mismatch. */
  57		if (unlikely(na->type != AT_UNUSED))
  58			return 0;
  59	} else {
  60		/* A fake inode describing an attribute. */
  61		if (ni->type != na->type)
  62			return 0;
  63		if (ni->name_len != na->name_len)
  64			return 0;
  65		if (na->name_len && memcmp(ni->name, na->name,
  66				na->name_len * sizeof(ntfschar)))
  67			return 0;
  68	}
  69	/* Match! */
  70	return 1;
  71}
  72
  73/**
  74 * ntfs_init_locked_inode - initialize an inode
  75 * @vi:		vfs inode to initialize
  76 * @data:	data which to initialize @vi to
  77 *
  78 * Initialize the vfs inode @vi with the values from the ntfs attribute @data in
  79 * order to enable ntfs_test_inode() to do its work.
  80 *
  81 * If initializing the normal file/directory inode, set @na->type to AT_UNUSED.
  82 * In that case, @na->name and @na->name_len should be set to NULL and 0,
  83 * respectively. Although that is not strictly necessary as
  84 * ntfs_read_locked_inode() will fill them in later.
  85 *
  86 * Return 0 on success and -errno on error.
  87 *
  88 * NOTE: This function runs with the inode->i_lock spin lock held so it is not
  89 * allowed to sleep. (Hence the GFP_ATOMIC allocation.)
  90 */
  91static int ntfs_init_locked_inode(struct inode *vi, void *data)
  92{
  93	ntfs_attr *na = (ntfs_attr *)data;
  94	ntfs_inode *ni = NTFS_I(vi);
  95
  96	vi->i_ino = na->mft_no;
  97
  98	ni->type = na->type;
  99	if (na->type == AT_INDEX_ALLOCATION)
 100		NInoSetMstProtected(ni);
 101
 102	ni->name = na->name;
 103	ni->name_len = na->name_len;
 104
 105	/* If initializing a normal inode, we are done. */
 106	if (likely(na->type == AT_UNUSED)) {
 107		BUG_ON(na->name);
 108		BUG_ON(na->name_len);
 109		return 0;
 110	}
 111
 112	/* It is a fake inode. */
 113	NInoSetAttr(ni);
 114
 115	/*
 116	 * We have I30 global constant as an optimization as it is the name
 117	 * in >99.9% of named attributes! The other <0.1% incur a GFP_ATOMIC
 118	 * allocation but that is ok. And most attributes are unnamed anyway,
 119	 * thus the fraction of named attributes with name != I30 is actually
 120	 * absolutely tiny.
 121	 */
 122	if (na->name_len && na->name != I30) {
 123		unsigned int i;
 124
 125		BUG_ON(!na->name);
 126		i = na->name_len * sizeof(ntfschar);
 127		ni->name = kmalloc(i + sizeof(ntfschar), GFP_ATOMIC);
 128		if (!ni->name)
 129			return -ENOMEM;
 130		memcpy(ni->name, na->name, i);
 131		ni->name[na->name_len] = 0;
 132	}
 133	return 0;
 134}
 135
 136static int ntfs_read_locked_inode(struct inode *vi);
 137static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi);
 138static int ntfs_read_locked_index_inode(struct inode *base_vi,
 139		struct inode *vi);
 140
 141/**
 142 * ntfs_iget - obtain a struct inode corresponding to a specific normal inode
 143 * @sb:		super block of mounted volume
 144 * @mft_no:	mft record number / inode number to obtain
 145 *
 146 * Obtain the struct inode corresponding to a specific normal inode (i.e. a
 147 * file or directory).
 148 *
 149 * If the inode is in the cache, it is just returned with an increased
 150 * reference count. Otherwise, a new struct inode is allocated and initialized,
 151 * and finally ntfs_read_locked_inode() is called to read in the inode and
 152 * fill in the remainder of the inode structure.
 153 *
 154 * Return the struct inode on success. Check the return value with IS_ERR() and
 155 * if true, the function failed and the error code is obtained from PTR_ERR().
 156 */
 157struct inode *ntfs_iget(struct super_block *sb, unsigned long mft_no)
 158{
 159	struct inode *vi;
 160	int err;
 161	ntfs_attr na;
 162
 163	na.mft_no = mft_no;
 164	na.type = AT_UNUSED;
 165	na.name = NULL;
 166	na.name_len = 0;
 167
 168	vi = iget5_locked(sb, mft_no, ntfs_test_inode,
 169			ntfs_init_locked_inode, &na);
 170	if (unlikely(!vi))
 171		return ERR_PTR(-ENOMEM);
 172
 173	err = 0;
 174
 175	/* If this is a freshly allocated inode, need to read it now. */
 176	if (vi->i_state & I_NEW) {
 177		err = ntfs_read_locked_inode(vi);
 178		unlock_new_inode(vi);
 179	}
 180	/*
 181	 * There is no point in keeping bad inodes around if the failure was
 182	 * due to ENOMEM. We want to be able to retry again later.
 183	 */
 184	if (unlikely(err == -ENOMEM)) {
 185		iput(vi);
 186		vi = ERR_PTR(err);
 187	}
 188	return vi;
 189}
 190
 191/**
 192 * ntfs_attr_iget - obtain a struct inode corresponding to an attribute
 193 * @base_vi:	vfs base inode containing the attribute
 194 * @type:	attribute type
 195 * @name:	Unicode name of the attribute (NULL if unnamed)
 196 * @name_len:	length of @name in Unicode characters (0 if unnamed)
 197 *
 198 * Obtain the (fake) struct inode corresponding to the attribute specified by
 199 * @type, @name, and @name_len, which is present in the base mft record
 200 * specified by the vfs inode @base_vi.
 201 *
 202 * If the attribute inode is in the cache, it is just returned with an
 203 * increased reference count. Otherwise, a new struct inode is allocated and
 204 * initialized, and finally ntfs_read_locked_attr_inode() is called to read the
 205 * attribute and fill in the inode structure.
 206 *
 207 * Note, for index allocation attributes, you need to use ntfs_index_iget()
 208 * instead of ntfs_attr_iget() as working with indices is a lot more complex.
 209 *
 210 * Return the struct inode of the attribute inode on success. Check the return
 211 * value with IS_ERR() and if true, the function failed and the error code is
 212 * obtained from PTR_ERR().
 213 */
 214struct inode *ntfs_attr_iget(struct inode *base_vi, ATTR_TYPE type,
 215		ntfschar *name, u32 name_len)
 216{
 217	struct inode *vi;
 218	int err;
 219	ntfs_attr na;
 220
 221	/* Make sure no one calls ntfs_attr_iget() for indices. */
 222	BUG_ON(type == AT_INDEX_ALLOCATION);
 223
 224	na.mft_no = base_vi->i_ino;
 225	na.type = type;
 226	na.name = name;
 227	na.name_len = name_len;
 228
 229	vi = iget5_locked(base_vi->i_sb, na.mft_no, ntfs_test_inode,
 230			ntfs_init_locked_inode, &na);
 231	if (unlikely(!vi))
 232		return ERR_PTR(-ENOMEM);
 233
 234	err = 0;
 235
 236	/* If this is a freshly allocated inode, need to read it now. */
 237	if (vi->i_state & I_NEW) {
 238		err = ntfs_read_locked_attr_inode(base_vi, vi);
 239		unlock_new_inode(vi);
 240	}
 241	/*
 242	 * There is no point in keeping bad attribute inodes around. This also
 243	 * simplifies things in that we never need to check for bad attribute
 244	 * inodes elsewhere.
 245	 */
 246	if (unlikely(err)) {
 247		iput(vi);
 248		vi = ERR_PTR(err);
 249	}
 250	return vi;
 251}
 252
 253/**
 254 * ntfs_index_iget - obtain a struct inode corresponding to an index
 255 * @base_vi:	vfs base inode containing the index related attributes
 256 * @name:	Unicode name of the index
 257 * @name_len:	length of @name in Unicode characters
 258 *
 259 * Obtain the (fake) struct inode corresponding to the index specified by @name
 260 * and @name_len, which is present in the base mft record specified by the vfs
 261 * inode @base_vi.
 262 *
 263 * If the index inode is in the cache, it is just returned with an increased
 264 * reference count.  Otherwise, a new struct inode is allocated and
 265 * initialized, and finally ntfs_read_locked_index_inode() is called to read
 266 * the index related attributes and fill in the inode structure.
 267 *
 268 * Return the struct inode of the index inode on success. Check the return
 269 * value with IS_ERR() and if true, the function failed and the error code is
 270 * obtained from PTR_ERR().
 271 */
 272struct inode *ntfs_index_iget(struct inode *base_vi, ntfschar *name,
 273		u32 name_len)
 274{
 275	struct inode *vi;
 276	int err;
 277	ntfs_attr na;
 278
 279	na.mft_no = base_vi->i_ino;
 280	na.type = AT_INDEX_ALLOCATION;
 281	na.name = name;
 282	na.name_len = name_len;
 283
 284	vi = iget5_locked(base_vi->i_sb, na.mft_no, ntfs_test_inode,
 285			ntfs_init_locked_inode, &na);
 286	if (unlikely(!vi))
 287		return ERR_PTR(-ENOMEM);
 288
 289	err = 0;
 290
 291	/* If this is a freshly allocated inode, need to read it now. */
 292	if (vi->i_state & I_NEW) {
 293		err = ntfs_read_locked_index_inode(base_vi, vi);
 294		unlock_new_inode(vi);
 295	}
 296	/*
 297	 * There is no point in keeping bad index inodes around.  This also
 298	 * simplifies things in that we never need to check for bad index
 299	 * inodes elsewhere.
 300	 */
 301	if (unlikely(err)) {
 302		iput(vi);
 303		vi = ERR_PTR(err);
 304	}
 305	return vi;
 306}
 307
 308struct inode *ntfs_alloc_big_inode(struct super_block *sb)
 309{
 310	ntfs_inode *ni;
 311
 312	ntfs_debug("Entering.");
 313	ni = alloc_inode_sb(sb, ntfs_big_inode_cache, GFP_NOFS);
 314	if (likely(ni != NULL)) {
 315		ni->state = 0;
 316		return VFS_I(ni);
 317	}
 318	ntfs_error(sb, "Allocation of NTFS big inode structure failed.");
 319	return NULL;
 320}
 321
 322void ntfs_free_big_inode(struct inode *inode)
 323{
 324	kmem_cache_free(ntfs_big_inode_cache, NTFS_I(inode));
 325}
 326
 327static inline ntfs_inode *ntfs_alloc_extent_inode(void)
 328{
 329	ntfs_inode *ni;
 330
 331	ntfs_debug("Entering.");
 332	ni = kmem_cache_alloc(ntfs_inode_cache, GFP_NOFS);
 333	if (likely(ni != NULL)) {
 334		ni->state = 0;
 335		return ni;
 336	}
 337	ntfs_error(NULL, "Allocation of NTFS inode structure failed.");
 338	return NULL;
 339}
 340
 341static void ntfs_destroy_extent_inode(ntfs_inode *ni)
 342{
 343	ntfs_debug("Entering.");
 344	BUG_ON(ni->page);
 345	if (!atomic_dec_and_test(&ni->count))
 346		BUG();
 347	kmem_cache_free(ntfs_inode_cache, ni);
 348}
 349
 350/*
 351 * The attribute runlist lock has separate locking rules from the
 352 * normal runlist lock, so split the two lock-classes:
 353 */
 354static struct lock_class_key attr_list_rl_lock_class;
 355
 356/**
 357 * __ntfs_init_inode - initialize ntfs specific part of an inode
 358 * @sb:		super block of mounted volume
 359 * @ni:		freshly allocated ntfs inode which to initialize
 360 *
 361 * Initialize an ntfs inode to defaults.
 362 *
 363 * NOTE: ni->mft_no, ni->state, ni->type, ni->name, and ni->name_len are left
 364 * untouched. Make sure to initialize them elsewhere.
 365 *
 366 * Return zero on success and -ENOMEM on error.
 367 */
 368void __ntfs_init_inode(struct super_block *sb, ntfs_inode *ni)
 369{
 370	ntfs_debug("Entering.");
 371	rwlock_init(&ni->size_lock);
 372	ni->initialized_size = ni->allocated_size = 0;
 373	ni->seq_no = 0;
 374	atomic_set(&ni->count, 1);
 375	ni->vol = NTFS_SB(sb);
 376	ntfs_init_runlist(&ni->runlist);
 377	mutex_init(&ni->mrec_lock);
 378	ni->page = NULL;
 379	ni->page_ofs = 0;
 380	ni->attr_list_size = 0;
 381	ni->attr_list = NULL;
 382	ntfs_init_runlist(&ni->attr_list_rl);
 383	lockdep_set_class(&ni->attr_list_rl.lock,
 384				&attr_list_rl_lock_class);
 385	ni->itype.index.block_size = 0;
 386	ni->itype.index.vcn_size = 0;
 387	ni->itype.index.collation_rule = 0;
 388	ni->itype.index.block_size_bits = 0;
 389	ni->itype.index.vcn_size_bits = 0;
 390	mutex_init(&ni->extent_lock);
 391	ni->nr_extents = 0;
 392	ni->ext.base_ntfs_ino = NULL;
 393}
 394
 395/*
 396 * Extent inodes get MFT-mapped in a nested way, while the base inode
 397 * is still mapped. Teach this nesting to the lock validator by creating
 398 * a separate class for nested inode's mrec_lock's:
 399 */
 400static struct lock_class_key extent_inode_mrec_lock_key;
 401
 402inline ntfs_inode *ntfs_new_extent_inode(struct super_block *sb,
 403		unsigned long mft_no)
 404{
 405	ntfs_inode *ni = ntfs_alloc_extent_inode();
 406
 407	ntfs_debug("Entering.");
 408	if (likely(ni != NULL)) {
 409		__ntfs_init_inode(sb, ni);
 410		lockdep_set_class(&ni->mrec_lock, &extent_inode_mrec_lock_key);
 411		ni->mft_no = mft_no;
 412		ni->type = AT_UNUSED;
 413		ni->name = NULL;
 414		ni->name_len = 0;
 415	}
 416	return ni;
 417}
 418
 419/**
 420 * ntfs_is_extended_system_file - check if a file is in the $Extend directory
 421 * @ctx:	initialized attribute search context
 422 *
 423 * Search all file name attributes in the inode described by the attribute
 424 * search context @ctx and check if any of the names are in the $Extend system
 425 * directory.
 426 *
 427 * Return values:
 428 *	   1: file is in $Extend directory
 429 *	   0: file is not in $Extend directory
 430 *    -errno: failed to determine if the file is in the $Extend directory
 431 */
 432static int ntfs_is_extended_system_file(ntfs_attr_search_ctx *ctx)
 433{
 434	int nr_links, err;
 435
 436	/* Restart search. */
 437	ntfs_attr_reinit_search_ctx(ctx);
 438
 439	/* Get number of hard links. */
 440	nr_links = le16_to_cpu(ctx->mrec->link_count);
 441
 442	/* Loop through all hard links. */
 443	while (!(err = ntfs_attr_lookup(AT_FILE_NAME, NULL, 0, 0, 0, NULL, 0,
 444			ctx))) {
 445		FILE_NAME_ATTR *file_name_attr;
 446		ATTR_RECORD *attr = ctx->attr;
 447		u8 *p, *p2;
 448
 449		nr_links--;
 450		/*
 451		 * Maximum sanity checking as we are called on an inode that
 452		 * we suspect might be corrupt.
 453		 */
 454		p = (u8*)attr + le32_to_cpu(attr->length);
 455		if (p < (u8*)ctx->mrec || (u8*)p > (u8*)ctx->mrec +
 456				le32_to_cpu(ctx->mrec->bytes_in_use)) {
 457err_corrupt_attr:
 458			ntfs_error(ctx->ntfs_ino->vol->sb, "Corrupt file name "
 459					"attribute. You should run chkdsk.");
 460			return -EIO;
 461		}
 462		if (attr->non_resident) {
 463			ntfs_error(ctx->ntfs_ino->vol->sb, "Non-resident file "
 464					"name. You should run chkdsk.");
 465			return -EIO;
 466		}
 467		if (attr->flags) {
 468			ntfs_error(ctx->ntfs_ino->vol->sb, "File name with "
 469					"invalid flags. You should run "
 470					"chkdsk.");
 471			return -EIO;
 472		}
 473		if (!(attr->data.resident.flags & RESIDENT_ATTR_IS_INDEXED)) {
 474			ntfs_error(ctx->ntfs_ino->vol->sb, "Unindexed file "
 475					"name. You should run chkdsk.");
 476			return -EIO;
 477		}
 478		file_name_attr = (FILE_NAME_ATTR*)((u8*)attr +
 479				le16_to_cpu(attr->data.resident.value_offset));
 480		p2 = (u8 *)file_name_attr + le32_to_cpu(attr->data.resident.value_length);
 481		if (p2 < (u8*)attr || p2 > p)
 482			goto err_corrupt_attr;
 483		/* This attribute is ok, but is it in the $Extend directory? */
 484		if (MREF_LE(file_name_attr->parent_directory) == FILE_Extend)
 485			return 1;	/* YES, it's an extended system file. */
 486	}
 487	if (unlikely(err != -ENOENT))
 488		return err;
 489	if (unlikely(nr_links)) {
 490		ntfs_error(ctx->ntfs_ino->vol->sb, "Inode hard link count "
 491				"doesn't match number of name attributes. You "
 492				"should run chkdsk.");
 493		return -EIO;
 494	}
 495	return 0;	/* NO, it is not an extended system file. */
 496}
 497
 498/**
 499 * ntfs_read_locked_inode - read an inode from its device
 500 * @vi:		inode to read
 501 *
 502 * ntfs_read_locked_inode() is called from ntfs_iget() to read the inode
 503 * described by @vi into memory from the device.
 504 *
 505 * The only fields in @vi that we need to/can look at when the function is
 506 * called are i_sb, pointing to the mounted device's super block, and i_ino,
 507 * the number of the inode to load.
 508 *
 509 * ntfs_read_locked_inode() maps, pins and locks the mft record number i_ino
 510 * for reading and sets up the necessary @vi fields as well as initializing
 511 * the ntfs inode.
 512 *
 513 * Q: What locks are held when the function is called?
 514 * A: i_state has I_NEW set, hence the inode is locked, also
 515 *    i_count is set to 1, so it is not going to go away
 516 *    i_flags is set to 0 and we have no business touching it.  Only an ioctl()
 517 *    is allowed to write to them. We should of course be honouring them but
 518 *    we need to do that using the IS_* macros defined in include/linux/fs.h.
 519 *    In any case ntfs_read_locked_inode() has nothing to do with i_flags.
 520 *
 521 * Return 0 on success and -errno on error.  In the error case, the inode will
 522 * have had make_bad_inode() executed on it.
 523 */
 524static int ntfs_read_locked_inode(struct inode *vi)
 525{
 526	ntfs_volume *vol = NTFS_SB(vi->i_sb);
 527	ntfs_inode *ni;
 528	struct inode *bvi;
 529	MFT_RECORD *m;
 530	ATTR_RECORD *a;
 531	STANDARD_INFORMATION *si;
 532	ntfs_attr_search_ctx *ctx;
 533	int err = 0;
 534
 535	ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
 536
 537	/* Setup the generic vfs inode parts now. */
 538	vi->i_uid = vol->uid;
 539	vi->i_gid = vol->gid;
 540	vi->i_mode = 0;
 541
 542	/*
 543	 * Initialize the ntfs specific part of @vi special casing
 544	 * FILE_MFT which we need to do at mount time.
 545	 */
 546	if (vi->i_ino != FILE_MFT)
 547		ntfs_init_big_inode(vi);
 548	ni = NTFS_I(vi);
 549
 550	m = map_mft_record(ni);
 551	if (IS_ERR(m)) {
 552		err = PTR_ERR(m);
 553		goto err_out;
 554	}
 555	ctx = ntfs_attr_get_search_ctx(ni, m);
 556	if (!ctx) {
 557		err = -ENOMEM;
 558		goto unm_err_out;
 559	}
 560
 561	if (!(m->flags & MFT_RECORD_IN_USE)) {
 562		ntfs_error(vi->i_sb, "Inode is not in use!");
 563		goto unm_err_out;
 564	}
 565	if (m->base_mft_record) {
 566		ntfs_error(vi->i_sb, "Inode is an extent inode!");
 567		goto unm_err_out;
 568	}
 569
 570	/* Transfer information from mft record into vfs and ntfs inodes. */
 571	vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);
 572
 573	/*
 574	 * FIXME: Keep in mind that link_count is two for files which have both
 575	 * a long file name and a short file name as separate entries, so if
 576	 * we are hiding short file names this will be too high. Either we need
 577	 * to account for the short file names by subtracting them or we need
 578	 * to make sure we delete files even though i_nlink is not zero which
 579	 * might be tricky due to vfs interactions. Need to think about this
 580	 * some more when implementing the unlink command.
 581	 */
 582	set_nlink(vi, le16_to_cpu(m->link_count));
 583	/*
 584	 * FIXME: Reparse points can have the directory bit set even though
 585	 * they would be S_IFLNK. Need to deal with this further below when we
 586	 * implement reparse points / symbolic links but it will do for now.
 587	 * Also if not a directory, it could be something else, rather than
 588	 * a regular file. But again, will do for now.
 589	 */
 590	/* Everyone gets all permissions. */
 591	vi->i_mode |= S_IRWXUGO;
 592	/* If read-only, no one gets write permissions. */
 593	if (IS_RDONLY(vi))
 594		vi->i_mode &= ~S_IWUGO;
 595	if (m->flags & MFT_RECORD_IS_DIRECTORY) {
 596		vi->i_mode |= S_IFDIR;
 597		/*
 598		 * Apply the directory permissions mask set in the mount
 599		 * options.
 600		 */
 601		vi->i_mode &= ~vol->dmask;
 602		/* Things break without this kludge! */
 603		if (vi->i_nlink > 1)
 604			set_nlink(vi, 1);
 605	} else {
 606		vi->i_mode |= S_IFREG;
 607		/* Apply the file permissions mask set in the mount options. */
 608		vi->i_mode &= ~vol->fmask;
 609	}
 610	/*
 611	 * Find the standard information attribute in the mft record. At this
 612	 * stage we haven't setup the attribute list stuff yet, so this could
 613	 * in fact fail if the standard information is in an extent record, but
 614	 * I don't think this actually ever happens.
 615	 */
 616	err = ntfs_attr_lookup(AT_STANDARD_INFORMATION, NULL, 0, 0, 0, NULL, 0,
 617			ctx);
 618	if (unlikely(err)) {
 619		if (err == -ENOENT) {
 620			/*
 621			 * TODO: We should be performing a hot fix here (if the
 622			 * recover mount option is set) by creating a new
 623			 * attribute.
 624			 */
 625			ntfs_error(vi->i_sb, "$STANDARD_INFORMATION attribute "
 626					"is missing.");
 627		}
 628		goto unm_err_out;
 629	}
 630	a = ctx->attr;
 631	/* Get the standard information attribute value. */
 632	if ((u8 *)a + le16_to_cpu(a->data.resident.value_offset)
 633			+ le32_to_cpu(a->data.resident.value_length) >
 634			(u8 *)ctx->mrec + vol->mft_record_size) {
 635		ntfs_error(vi->i_sb, "Corrupt standard information attribute in inode.");
 636		goto unm_err_out;
 637	}
 638	si = (STANDARD_INFORMATION*)((u8*)a +
 639			le16_to_cpu(a->data.resident.value_offset));
 640
 641	/* Transfer information from the standard information into vi. */
 642	/*
 643	 * Note: The i_?times do not quite map perfectly onto the NTFS times,
 644	 * but they are close enough, and in the end it doesn't really matter
 645	 * that much...
 646	 */
 647	/*
 648	 * mtime is the last change of the data within the file. Not changed
 649	 * when only metadata is changed, e.g. a rename doesn't affect mtime.
 650	 */
 651	vi->i_mtime = ntfs2utc(si->last_data_change_time);
 652	/*
 653	 * ctime is the last change of the metadata of the file. This obviously
 654	 * always changes, when mtime is changed. ctime can be changed on its
 655	 * own, mtime is then not changed, e.g. when a file is renamed.
 656	 */
 657	vi->i_ctime = ntfs2utc(si->last_mft_change_time);
 658	/*
 659	 * Last access to the data within the file. Not changed during a rename
 660	 * for example but changed whenever the file is written to.
 661	 */
 662	vi->i_atime = ntfs2utc(si->last_access_time);
 663
 664	/* Find the attribute list attribute if present. */
 665	ntfs_attr_reinit_search_ctx(ctx);
 666	err = ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, 0, 0, NULL, 0, ctx);
 667	if (err) {
 668		if (unlikely(err != -ENOENT)) {
 669			ntfs_error(vi->i_sb, "Failed to lookup attribute list "
 670					"attribute.");
 671			goto unm_err_out;
 672		}
 673	} else /* if (!err) */ {
 674		if (vi->i_ino == FILE_MFT)
 675			goto skip_attr_list_load;
 676		ntfs_debug("Attribute list found in inode 0x%lx.", vi->i_ino);
 677		NInoSetAttrList(ni);
 678		a = ctx->attr;
 679		if (a->flags & ATTR_COMPRESSION_MASK) {
 680			ntfs_error(vi->i_sb, "Attribute list attribute is "
 681					"compressed.");
 682			goto unm_err_out;
 683		}
 684		if (a->flags & ATTR_IS_ENCRYPTED ||
 685				a->flags & ATTR_IS_SPARSE) {
 686			if (a->non_resident) {
 687				ntfs_error(vi->i_sb, "Non-resident attribute "
 688						"list attribute is encrypted/"
 689						"sparse.");
 690				goto unm_err_out;
 691			}
 692			ntfs_warning(vi->i_sb, "Resident attribute list "
 693					"attribute in inode 0x%lx is marked "
 694					"encrypted/sparse which is not true.  "
 695					"However, Windows allows this and "
 696					"chkdsk does not detect or correct it "
 697					"so we will just ignore the invalid "
 698					"flags and pretend they are not set.",
 699					vi->i_ino);
 700		}
 701		/* Now allocate memory for the attribute list. */
 702		ni->attr_list_size = (u32)ntfs_attr_size(a);
 703		ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
 704		if (!ni->attr_list) {
 705			ntfs_error(vi->i_sb, "Not enough memory to allocate "
 706					"buffer for attribute list.");
 707			err = -ENOMEM;
 708			goto unm_err_out;
 709		}
 710		if (a->non_resident) {
 711			NInoSetAttrListNonResident(ni);
 712			if (a->data.non_resident.lowest_vcn) {
 713				ntfs_error(vi->i_sb, "Attribute list has non "
 714						"zero lowest_vcn.");
 715				goto unm_err_out;
 716			}
 717			/*
 718			 * Setup the runlist. No need for locking as we have
 719			 * exclusive access to the inode at this time.
 720			 */
 721			ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
 722					a, NULL);
 723			if (IS_ERR(ni->attr_list_rl.rl)) {
 724				err = PTR_ERR(ni->attr_list_rl.rl);
 725				ni->attr_list_rl.rl = NULL;
 726				ntfs_error(vi->i_sb, "Mapping pairs "
 727						"decompression failed.");
 728				goto unm_err_out;
 729			}
 730			/* Now load the attribute list. */
 731			if ((err = load_attribute_list(vol, &ni->attr_list_rl,
 732					ni->attr_list, ni->attr_list_size,
 733					sle64_to_cpu(a->data.non_resident.
 734					initialized_size)))) {
 735				ntfs_error(vi->i_sb, "Failed to load "
 736						"attribute list attribute.");
 737				goto unm_err_out;
 738			}
 739		} else /* if (!a->non_resident) */ {
 740			if ((u8*)a + le16_to_cpu(a->data.resident.value_offset)
 741					+ le32_to_cpu(
 742					a->data.resident.value_length) >
 743					(u8*)ctx->mrec + vol->mft_record_size) {
 744				ntfs_error(vi->i_sb, "Corrupt attribute list "
 745						"in inode.");
 746				goto unm_err_out;
 747			}
 748			/* Now copy the attribute list. */
 749			memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
 750					a->data.resident.value_offset),
 751					le32_to_cpu(
 752					a->data.resident.value_length));
 753		}
 754	}
 755skip_attr_list_load:
 756	/*
 757	 * If an attribute list is present we now have the attribute list value
 758	 * in ntfs_ino->attr_list and it is ntfs_ino->attr_list_size bytes.
 759	 */
 760	if (S_ISDIR(vi->i_mode)) {
 761		loff_t bvi_size;
 762		ntfs_inode *bni;
 763		INDEX_ROOT *ir;
 764		u8 *ir_end, *index_end;
 765
 766		/* It is a directory, find index root attribute. */
 767		ntfs_attr_reinit_search_ctx(ctx);
 768		err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE,
 769				0, NULL, 0, ctx);
 770		if (unlikely(err)) {
 771			if (err == -ENOENT) {
 772				// FIXME: File is corrupt! Hot-fix with empty
 773				// index root attribute if recovery option is
 774				// set.
 775				ntfs_error(vi->i_sb, "$INDEX_ROOT attribute "
 776						"is missing.");
 777			}
 778			goto unm_err_out;
 779		}
 780		a = ctx->attr;
 781		/* Set up the state. */
 782		if (unlikely(a->non_resident)) {
 783			ntfs_error(vol->sb, "$INDEX_ROOT attribute is not "
 784					"resident.");
 785			goto unm_err_out;
 786		}
 787		/* Ensure the attribute name is placed before the value. */
 788		if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
 789				le16_to_cpu(a->data.resident.value_offset)))) {
 790			ntfs_error(vol->sb, "$INDEX_ROOT attribute name is "
 791					"placed after the attribute value.");
 792			goto unm_err_out;
 793		}
 794		/*
 795		 * Compressed/encrypted index root just means that the newly
 796		 * created files in that directory should be created compressed/
 797		 * encrypted. However index root cannot be both compressed and
 798		 * encrypted.
 799		 */
 800		if (a->flags & ATTR_COMPRESSION_MASK)
 801			NInoSetCompressed(ni);
 802		if (a->flags & ATTR_IS_ENCRYPTED) {
 803			if (a->flags & ATTR_COMPRESSION_MASK) {
 804				ntfs_error(vi->i_sb, "Found encrypted and "
 805						"compressed attribute.");
 806				goto unm_err_out;
 807			}
 808			NInoSetEncrypted(ni);
 809		}
 810		if (a->flags & ATTR_IS_SPARSE)
 811			NInoSetSparse(ni);
 812		ir = (INDEX_ROOT*)((u8*)a +
 813				le16_to_cpu(a->data.resident.value_offset));
 814		ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
 815		if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
 816			ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
 817					"corrupt.");
 818			goto unm_err_out;
 819		}
 820		index_end = (u8*)&ir->index +
 821				le32_to_cpu(ir->index.index_length);
 822		if (index_end > ir_end) {
 823			ntfs_error(vi->i_sb, "Directory index is corrupt.");
 824			goto unm_err_out;
 825		}
 826		if (ir->type != AT_FILE_NAME) {
 827			ntfs_error(vi->i_sb, "Indexed attribute is not "
 828					"$FILE_NAME.");
 829			goto unm_err_out;
 830		}
 831		if (ir->collation_rule != COLLATION_FILE_NAME) {
 832			ntfs_error(vi->i_sb, "Index collation rule is not "
 833					"COLLATION_FILE_NAME.");
 834			goto unm_err_out;
 835		}
 836		ni->itype.index.collation_rule = ir->collation_rule;
 837		ni->itype.index.block_size = le32_to_cpu(ir->index_block_size);
 838		if (ni->itype.index.block_size &
 839				(ni->itype.index.block_size - 1)) {
 840			ntfs_error(vi->i_sb, "Index block size (%u) is not a "
 841					"power of two.",
 842					ni->itype.index.block_size);
 843			goto unm_err_out;
 844		}
 845		if (ni->itype.index.block_size > PAGE_SIZE) {
 846			ntfs_error(vi->i_sb, "Index block size (%u) > "
 847					"PAGE_SIZE (%ld) is not "
 848					"supported.  Sorry.",
 849					ni->itype.index.block_size,
 850					PAGE_SIZE);
 851			err = -EOPNOTSUPP;
 852			goto unm_err_out;
 853		}
 854		if (ni->itype.index.block_size < NTFS_BLOCK_SIZE) {
 855			ntfs_error(vi->i_sb, "Index block size (%u) < "
 856					"NTFS_BLOCK_SIZE (%i) is not "
 857					"supported.  Sorry.",
 858					ni->itype.index.block_size,
 859					NTFS_BLOCK_SIZE);
 860			err = -EOPNOTSUPP;
 861			goto unm_err_out;
 862		}
 863		ni->itype.index.block_size_bits =
 864				ffs(ni->itype.index.block_size) - 1;
 865		/* Determine the size of a vcn in the directory index. */
 866		if (vol->cluster_size <= ni->itype.index.block_size) {
 867			ni->itype.index.vcn_size = vol->cluster_size;
 868			ni->itype.index.vcn_size_bits = vol->cluster_size_bits;
 869		} else {
 870			ni->itype.index.vcn_size = vol->sector_size;
 871			ni->itype.index.vcn_size_bits = vol->sector_size_bits;
 872		}
 873
 874		/* Setup the index allocation attribute, even if not present. */
 875		NInoSetMstProtected(ni);
 876		ni->type = AT_INDEX_ALLOCATION;
 877		ni->name = I30;
 878		ni->name_len = 4;
 879
 880		if (!(ir->index.flags & LARGE_INDEX)) {
 881			/* No index allocation. */
 882			vi->i_size = ni->initialized_size =
 883					ni->allocated_size = 0;
 884			/* We are done with the mft record, so we release it. */
 885			ntfs_attr_put_search_ctx(ctx);
 886			unmap_mft_record(ni);
 887			m = NULL;
 888			ctx = NULL;
 889			goto skip_large_dir_stuff;
 890		} /* LARGE_INDEX: Index allocation present. Setup state. */
 891		NInoSetIndexAllocPresent(ni);
 892		/* Find index allocation attribute. */
 893		ntfs_attr_reinit_search_ctx(ctx);
 894		err = ntfs_attr_lookup(AT_INDEX_ALLOCATION, I30, 4,
 895				CASE_SENSITIVE, 0, NULL, 0, ctx);
 896		if (unlikely(err)) {
 897			if (err == -ENOENT)
 898				ntfs_error(vi->i_sb, "$INDEX_ALLOCATION "
 899						"attribute is not present but "
 900						"$INDEX_ROOT indicated it is.");
 901			else
 902				ntfs_error(vi->i_sb, "Failed to lookup "
 903						"$INDEX_ALLOCATION "
 904						"attribute.");
 905			goto unm_err_out;
 906		}
 907		a = ctx->attr;
 908		if (!a->non_resident) {
 909			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 910					"is resident.");
 911			goto unm_err_out;
 912		}
 913		/*
 914		 * Ensure the attribute name is placed before the mapping pairs
 915		 * array.
 916		 */
 917		if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
 918				le16_to_cpu(
 919				a->data.non_resident.mapping_pairs_offset)))) {
 920			ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name "
 921					"is placed after the mapping pairs "
 922					"array.");
 923			goto unm_err_out;
 924		}
 925		if (a->flags & ATTR_IS_ENCRYPTED) {
 926			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 927					"is encrypted.");
 928			goto unm_err_out;
 929		}
 930		if (a->flags & ATTR_IS_SPARSE) {
 931			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 932					"is sparse.");
 933			goto unm_err_out;
 934		}
 935		if (a->flags & ATTR_COMPRESSION_MASK) {
 936			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 937					"is compressed.");
 938			goto unm_err_out;
 939		}
 940		if (a->data.non_resident.lowest_vcn) {
 941			ntfs_error(vi->i_sb, "First extent of "
 942					"$INDEX_ALLOCATION attribute has non "
 943					"zero lowest_vcn.");
 944			goto unm_err_out;
 945		}
 946		vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
 947		ni->initialized_size = sle64_to_cpu(
 948				a->data.non_resident.initialized_size);
 949		ni->allocated_size = sle64_to_cpu(
 950				a->data.non_resident.allocated_size);
 951		/*
 952		 * We are done with the mft record, so we release it. Otherwise
 953		 * we would deadlock in ntfs_attr_iget().
 954		 */
 955		ntfs_attr_put_search_ctx(ctx);
 956		unmap_mft_record(ni);
 957		m = NULL;
 958		ctx = NULL;
 959		/* Get the index bitmap attribute inode. */
 960		bvi = ntfs_attr_iget(vi, AT_BITMAP, I30, 4);
 961		if (IS_ERR(bvi)) {
 962			ntfs_error(vi->i_sb, "Failed to get bitmap attribute.");
 963			err = PTR_ERR(bvi);
 964			goto unm_err_out;
 965		}
 966		bni = NTFS_I(bvi);
 967		if (NInoCompressed(bni) || NInoEncrypted(bni) ||
 968				NInoSparse(bni)) {
 969			ntfs_error(vi->i_sb, "$BITMAP attribute is compressed "
 970					"and/or encrypted and/or sparse.");
 971			goto iput_unm_err_out;
 972		}
 973		/* Consistency check bitmap size vs. index allocation size. */
 974		bvi_size = i_size_read(bvi);
 975		if ((bvi_size << 3) < (vi->i_size >>
 976				ni->itype.index.block_size_bits)) {
 977			ntfs_error(vi->i_sb, "Index bitmap too small (0x%llx) "
 978					"for index allocation (0x%llx).",
 979					bvi_size << 3, vi->i_size);
 980			goto iput_unm_err_out;
 981		}
 982		/* No longer need the bitmap attribute inode. */
 983		iput(bvi);
 984skip_large_dir_stuff:
 985		/* Setup the operations for this inode. */
 986		vi->i_op = &ntfs_dir_inode_ops;
 987		vi->i_fop = &ntfs_dir_ops;
 988		vi->i_mapping->a_ops = &ntfs_mst_aops;
 989	} else {
 990		/* It is a file. */
 991		ntfs_attr_reinit_search_ctx(ctx);
 992
 993		/* Setup the data attribute, even if not present. */
 994		ni->type = AT_DATA;
 995		ni->name = NULL;
 996		ni->name_len = 0;
 997
 998		/* Find first extent of the unnamed data attribute. */
 999		err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, 0, NULL, 0, ctx);
1000		if (unlikely(err)) {
1001			vi->i_size = ni->initialized_size =
1002					ni->allocated_size = 0;
1003			if (err != -ENOENT) {
1004				ntfs_error(vi->i_sb, "Failed to lookup $DATA "
1005						"attribute.");
1006				goto unm_err_out;
1007			}
1008			/*
1009			 * FILE_Secure does not have an unnamed $DATA
1010			 * attribute, so we special case it here.
1011			 */
1012			if (vi->i_ino == FILE_Secure)
1013				goto no_data_attr_special_case;
1014			/*
1015			 * Most if not all the system files in the $Extend
1016			 * system directory do not have unnamed data
1017			 * attributes so we need to check if the parent
1018			 * directory of the file is FILE_Extend and if it is
1019			 * ignore this error. To do this we need to get the
1020			 * name of this inode from the mft record as the name
1021			 * contains the back reference to the parent directory.
1022			 */
1023			if (ntfs_is_extended_system_file(ctx) > 0)
1024				goto no_data_attr_special_case;
1025			// FIXME: File is corrupt! Hot-fix with empty data
1026			// attribute if recovery option is set.
1027			ntfs_error(vi->i_sb, "$DATA attribute is missing.");
1028			goto unm_err_out;
1029		}
1030		a = ctx->attr;
1031		/* Setup the state. */
1032		if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) {
1033			if (a->flags & ATTR_COMPRESSION_MASK) {
1034				NInoSetCompressed(ni);
1035				if (vol->cluster_size > 4096) {
1036					ntfs_error(vi->i_sb, "Found "
1037							"compressed data but "
1038							"compression is "
1039							"disabled due to "
1040							"cluster size (%i) > "
1041							"4kiB.",
1042							vol->cluster_size);
1043					goto unm_err_out;
1044				}
1045				if ((a->flags & ATTR_COMPRESSION_MASK)
1046						!= ATTR_IS_COMPRESSED) {
1047					ntfs_error(vi->i_sb, "Found unknown "
1048							"compression method "
1049							"or corrupt file.");
1050					goto unm_err_out;
1051				}
1052			}
1053			if (a->flags & ATTR_IS_SPARSE)
1054				NInoSetSparse(ni);
1055		}
1056		if (a->flags & ATTR_IS_ENCRYPTED) {
1057			if (NInoCompressed(ni)) {
1058				ntfs_error(vi->i_sb, "Found encrypted and "
1059						"compressed data.");
1060				goto unm_err_out;
1061			}
1062			NInoSetEncrypted(ni);
1063		}
1064		if (a->non_resident) {
1065			NInoSetNonResident(ni);
1066			if (NInoCompressed(ni) || NInoSparse(ni)) {
1067				if (NInoCompressed(ni) && a->data.non_resident.
1068						compression_unit != 4) {
1069					ntfs_error(vi->i_sb, "Found "
1070							"non-standard "
1071							"compression unit (%u "
1072							"instead of 4).  "
1073							"Cannot handle this.",
1074							a->data.non_resident.
1075							compression_unit);
1076					err = -EOPNOTSUPP;
1077					goto unm_err_out;
1078				}
1079				if (a->data.non_resident.compression_unit) {
1080					ni->itype.compressed.block_size = 1U <<
1081							(a->data.non_resident.
1082							compression_unit +
1083							vol->cluster_size_bits);
1084					ni->itype.compressed.block_size_bits =
1085							ffs(ni->itype.
1086							compressed.
1087							block_size) - 1;
1088					ni->itype.compressed.block_clusters =
1089							1U << a->data.
1090							non_resident.
1091							compression_unit;
1092				} else {
1093					ni->itype.compressed.block_size = 0;
1094					ni->itype.compressed.block_size_bits =
1095							0;
1096					ni->itype.compressed.block_clusters =
1097							0;
1098				}
1099				ni->itype.compressed.size = sle64_to_cpu(
1100						a->data.non_resident.
1101						compressed_size);
1102			}
1103			if (a->data.non_resident.lowest_vcn) {
1104				ntfs_error(vi->i_sb, "First extent of $DATA "
1105						"attribute has non zero "
1106						"lowest_vcn.");
1107				goto unm_err_out;
1108			}
1109			vi->i_size = sle64_to_cpu(
1110					a->data.non_resident.data_size);
1111			ni->initialized_size = sle64_to_cpu(
1112					a->data.non_resident.initialized_size);
1113			ni->allocated_size = sle64_to_cpu(
1114					a->data.non_resident.allocated_size);
1115		} else { /* Resident attribute. */
1116			vi->i_size = ni->initialized_size = le32_to_cpu(
1117					a->data.resident.value_length);
1118			ni->allocated_size = le32_to_cpu(a->length) -
1119					le16_to_cpu(
1120					a->data.resident.value_offset);
1121			if (vi->i_size > ni->allocated_size) {
1122				ntfs_error(vi->i_sb, "Resident data attribute "
1123						"is corrupt (size exceeds "
1124						"allocation).");
1125				goto unm_err_out;
1126			}
1127		}
1128no_data_attr_special_case:
1129		/* We are done with the mft record, so we release it. */
1130		ntfs_attr_put_search_ctx(ctx);
1131		unmap_mft_record(ni);
1132		m = NULL;
1133		ctx = NULL;
1134		/* Setup the operations for this inode. */
1135		vi->i_op = &ntfs_file_inode_ops;
1136		vi->i_fop = &ntfs_file_ops;
1137		vi->i_mapping->a_ops = &ntfs_normal_aops;
1138		if (NInoMstProtected(ni))
1139			vi->i_mapping->a_ops = &ntfs_mst_aops;
1140		else if (NInoCompressed(ni))
1141			vi->i_mapping->a_ops = &ntfs_compressed_aops;
1142	}
1143	/*
1144	 * The number of 512-byte blocks used on disk (for stat). This is in so
1145	 * far inaccurate as it doesn't account for any named streams or other
1146	 * special non-resident attributes, but that is how Windows works, too,
1147	 * so we are at least consistent with Windows, if not entirely
1148	 * consistent with the Linux Way. Doing it the Linux Way would cause a
1149	 * significant slowdown as it would involve iterating over all
1150	 * attributes in the mft record and adding the allocated/compressed
1151	 * sizes of all non-resident attributes present to give us the Linux
1152	 * correct size that should go into i_blocks (after division by 512).
1153	 */
1154	if (S_ISREG(vi->i_mode) && (NInoCompressed(ni) || NInoSparse(ni)))
1155		vi->i_blocks = ni->itype.compressed.size >> 9;
1156	else
1157		vi->i_blocks = ni->allocated_size >> 9;
1158	ntfs_debug("Done.");
1159	return 0;
1160iput_unm_err_out:
1161	iput(bvi);
1162unm_err_out:
1163	if (!err)
1164		err = -EIO;
1165	if (ctx)
1166		ntfs_attr_put_search_ctx(ctx);
1167	if (m)
1168		unmap_mft_record(ni);
1169err_out:
1170	ntfs_error(vol->sb, "Failed with error code %i.  Marking corrupt "
1171			"inode 0x%lx as bad.  Run chkdsk.", err, vi->i_ino);
1172	make_bad_inode(vi);
1173	if (err != -EOPNOTSUPP && err != -ENOMEM)
1174		NVolSetErrors(vol);
1175	return err;
1176}
1177
1178/**
1179 * ntfs_read_locked_attr_inode - read an attribute inode from its base inode
1180 * @base_vi:	base inode
1181 * @vi:		attribute inode to read
1182 *
1183 * ntfs_read_locked_attr_inode() is called from ntfs_attr_iget() to read the
1184 * attribute inode described by @vi into memory from the base mft record
1185 * described by @base_ni.
1186 *
1187 * ntfs_read_locked_attr_inode() maps, pins and locks the base inode for
1188 * reading and looks up the attribute described by @vi before setting up the
1189 * necessary fields in @vi as well as initializing the ntfs inode.
1190 *
1191 * Q: What locks are held when the function is called?
1192 * A: i_state has I_NEW set, hence the inode is locked, also
1193 *    i_count is set to 1, so it is not going to go away
1194 *
1195 * Return 0 on success and -errno on error.  In the error case, the inode will
1196 * have had make_bad_inode() executed on it.
1197 *
1198 * Note this cannot be called for AT_INDEX_ALLOCATION.
1199 */
1200static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi)
1201{
1202	ntfs_volume *vol = NTFS_SB(vi->i_sb);
1203	ntfs_inode *ni, *base_ni;
1204	MFT_RECORD *m;
1205	ATTR_RECORD *a;
1206	ntfs_attr_search_ctx *ctx;
1207	int err = 0;
1208
1209	ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
1210
1211	ntfs_init_big_inode(vi);
1212
1213	ni	= NTFS_I(vi);
1214	base_ni = NTFS_I(base_vi);
1215
1216	/* Just mirror the values from the base inode. */
1217	vi->i_uid	= base_vi->i_uid;
1218	vi->i_gid	= base_vi->i_gid;
1219	set_nlink(vi, base_vi->i_nlink);
1220	vi->i_mtime	= base_vi->i_mtime;
1221	vi->i_ctime	= base_vi->i_ctime;
1222	vi->i_atime	= base_vi->i_atime;
1223	vi->i_generation = ni->seq_no = base_ni->seq_no;
1224
1225	/* Set inode type to zero but preserve permissions. */
1226	vi->i_mode	= base_vi->i_mode & ~S_IFMT;
1227
1228	m = map_mft_record(base_ni);
1229	if (IS_ERR(m)) {
1230		err = PTR_ERR(m);
1231		goto err_out;
1232	}
1233	ctx = ntfs_attr_get_search_ctx(base_ni, m);
1234	if (!ctx) {
1235		err = -ENOMEM;
1236		goto unm_err_out;
1237	}
1238	/* Find the attribute. */
1239	err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
1240			CASE_SENSITIVE, 0, NULL, 0, ctx);
1241	if (unlikely(err))
1242		goto unm_err_out;
1243	a = ctx->attr;
1244	if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) {
1245		if (a->flags & ATTR_COMPRESSION_MASK) {
1246			NInoSetCompressed(ni);
1247			if ((ni->type != AT_DATA) || (ni->type == AT_DATA &&
1248					ni->name_len)) {
1249				ntfs_error(vi->i_sb, "Found compressed "
1250						"non-data or named data "
1251						"attribute.  Please report "
1252						"you saw this message to "
1253						"linux-ntfs-dev@lists."
1254						"sourceforge.net");
1255				goto unm_err_out;
1256			}
1257			if (vol->cluster_size > 4096) {
1258				ntfs_error(vi->i_sb, "Found compressed "
1259						"attribute but compression is "
1260						"disabled due to cluster size "
1261						"(%i) > 4kiB.",
1262						vol->cluster_size);
1263				goto unm_err_out;
1264			}
1265			if ((a->flags & ATTR_COMPRESSION_MASK) !=
1266					ATTR_IS_COMPRESSED) {
1267				ntfs_error(vi->i_sb, "Found unknown "
1268						"compression method.");
1269				goto unm_err_out;
1270			}
1271		}
1272		/*
1273		 * The compressed/sparse flag set in an index root just means
1274		 * to compress all files.
1275		 */
1276		if (NInoMstProtected(ni) && ni->type != AT_INDEX_ROOT) {
1277			ntfs_error(vi->i_sb, "Found mst protected attribute "
1278					"but the attribute is %s.  Please "
1279					"report you saw this message to "
1280					"linux-ntfs-dev@lists.sourceforge.net",
1281					NInoCompressed(ni) ? "compressed" :
1282					"sparse");
1283			goto unm_err_out;
1284		}
1285		if (a->flags & ATTR_IS_SPARSE)
1286			NInoSetSparse(ni);
1287	}
1288	if (a->flags & ATTR_IS_ENCRYPTED) {
1289		if (NInoCompressed(ni)) {
1290			ntfs_error(vi->i_sb, "Found encrypted and compressed "
1291					"data.");
1292			goto unm_err_out;
1293		}
1294		/*
1295		 * The encryption flag set in an index root just means to
1296		 * encrypt all files.
1297		 */
1298		if (NInoMstProtected(ni) && ni->type != AT_INDEX_ROOT) {
1299			ntfs_error(vi->i_sb, "Found mst protected attribute "
1300					"but the attribute is encrypted.  "
1301					"Please report you saw this message "
1302					"to linux-ntfs-dev@lists.sourceforge."
1303					"net");
1304			goto unm_err_out;
1305		}
1306		if (ni->type != AT_DATA) {
1307			ntfs_error(vi->i_sb, "Found encrypted non-data "
1308					"attribute.");
1309			goto unm_err_out;
1310		}
1311		NInoSetEncrypted(ni);
1312	}
1313	if (!a->non_resident) {
1314		/* Ensure the attribute name is placed before the value. */
1315		if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1316				le16_to_cpu(a->data.resident.value_offset)))) {
1317			ntfs_error(vol->sb, "Attribute name is placed after "
1318					"the attribute value.");
1319			goto unm_err_out;
1320		}
1321		if (NInoMstProtected(ni)) {
1322			ntfs_error(vi->i_sb, "Found mst protected attribute "
1323					"but the attribute is resident.  "
1324					"Please report you saw this message to "
1325					"linux-ntfs-dev@lists.sourceforge.net");
1326			goto unm_err_out;
1327		}
1328		vi->i_size = ni->initialized_size = le32_to_cpu(
1329				a->data.resident.value_length);
1330		ni->allocated_size = le32_to_cpu(a->length) -
1331				le16_to_cpu(a->data.resident.value_offset);
1332		if (vi->i_size > ni->allocated_size) {
1333			ntfs_error(vi->i_sb, "Resident attribute is corrupt "
1334					"(size exceeds allocation).");
1335			goto unm_err_out;
1336		}
1337	} else {
1338		NInoSetNonResident(ni);
1339		/*
1340		 * Ensure the attribute name is placed before the mapping pairs
1341		 * array.
1342		 */
1343		if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1344				le16_to_cpu(
1345				a->data.non_resident.mapping_pairs_offset)))) {
1346			ntfs_error(vol->sb, "Attribute name is placed after "
1347					"the mapping pairs array.");
1348			goto unm_err_out;
1349		}
1350		if (NInoCompressed(ni) || NInoSparse(ni)) {
1351			if (NInoCompressed(ni) && a->data.non_resident.
1352					compression_unit != 4) {
1353				ntfs_error(vi->i_sb, "Found non-standard "
1354						"compression unit (%u instead "
1355						"of 4).  Cannot handle this.",
1356						a->data.non_resident.
1357						compression_unit);
1358				err = -EOPNOTSUPP;
1359				goto unm_err_out;
1360			}
1361			if (a->data.non_resident.compression_unit) {
1362				ni->itype.compressed.block_size = 1U <<
1363						(a->data.non_resident.
1364						compression_unit +
1365						vol->cluster_size_bits);
1366				ni->itype.compressed.block_size_bits =
1367						ffs(ni->itype.compressed.
1368						block_size) - 1;
1369				ni->itype.compressed.block_clusters = 1U <<
1370						a->data.non_resident.
1371						compression_unit;
1372			} else {
1373				ni->itype.compressed.block_size = 0;
1374				ni->itype.compressed.block_size_bits = 0;
1375				ni->itype.compressed.block_clusters = 0;
1376			}
1377			ni->itype.compressed.size = sle64_to_cpu(
1378					a->data.non_resident.compressed_size);
1379		}
1380		if (a->data.non_resident.lowest_vcn) {
1381			ntfs_error(vi->i_sb, "First extent of attribute has "
1382					"non-zero lowest_vcn.");
1383			goto unm_err_out;
1384		}
1385		vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
1386		ni->initialized_size = sle64_to_cpu(
1387				a->data.non_resident.initialized_size);
1388		ni->allocated_size = sle64_to_cpu(
1389				a->data.non_resident.allocated_size);
1390	}
1391	vi->i_mapping->a_ops = &ntfs_normal_aops;
1392	if (NInoMstProtected(ni))
1393		vi->i_mapping->a_ops = &ntfs_mst_aops;
1394	else if (NInoCompressed(ni))
1395		vi->i_mapping->a_ops = &ntfs_compressed_aops;
1396	if ((NInoCompressed(ni) || NInoSparse(ni)) && ni->type != AT_INDEX_ROOT)
1397		vi->i_blocks = ni->itype.compressed.size >> 9;
1398	else
1399		vi->i_blocks = ni->allocated_size >> 9;
1400	/*
1401	 * Make sure the base inode does not go away and attach it to the
1402	 * attribute inode.
1403	 */
1404	igrab(base_vi);
1405	ni->ext.base_ntfs_ino = base_ni;
1406	ni->nr_extents = -1;
1407
1408	ntfs_attr_put_search_ctx(ctx);
1409	unmap_mft_record(base_ni);
1410
1411	ntfs_debug("Done.");
1412	return 0;
1413
1414unm_err_out:
1415	if (!err)
1416		err = -EIO;
1417	if (ctx)
1418		ntfs_attr_put_search_ctx(ctx);
1419	unmap_mft_record(base_ni);
1420err_out:
1421	ntfs_error(vol->sb, "Failed with error code %i while reading attribute "
1422			"inode (mft_no 0x%lx, type 0x%x, name_len %i).  "
1423			"Marking corrupt inode and base inode 0x%lx as bad.  "
1424			"Run chkdsk.", err, vi->i_ino, ni->type, ni->name_len,
1425			base_vi->i_ino);
1426	make_bad_inode(vi);
1427	if (err != -ENOMEM)
1428		NVolSetErrors(vol);
1429	return err;
1430}
1431
1432/**
1433 * ntfs_read_locked_index_inode - read an index inode from its base inode
1434 * @base_vi:	base inode
1435 * @vi:		index inode to read
1436 *
1437 * ntfs_read_locked_index_inode() is called from ntfs_index_iget() to read the
1438 * index inode described by @vi into memory from the base mft record described
1439 * by @base_ni.
1440 *
1441 * ntfs_read_locked_index_inode() maps, pins and locks the base inode for
1442 * reading and looks up the attributes relating to the index described by @vi
1443 * before setting up the necessary fields in @vi as well as initializing the
1444 * ntfs inode.
1445 *
1446 * Note, index inodes are essentially attribute inodes (NInoAttr() is true)
1447 * with the attribute type set to AT_INDEX_ALLOCATION.  Apart from that, they
1448 * are setup like directory inodes since directories are a special case of
1449 * indices ao they need to be treated in much the same way.  Most importantly,
1450 * for small indices the index allocation attribute might not actually exist.
1451 * However, the index root attribute always exists but this does not need to
1452 * have an inode associated with it and this is why we define a new inode type
1453 * index.  Also, like for directories, we need to have an attribute inode for
1454 * the bitmap attribute corresponding to the index allocation attribute and we
1455 * can store this in the appropriate field of the inode, just like we do for
1456 * normal directory inodes.
1457 *
1458 * Q: What locks are held when the function is called?
1459 * A: i_state has I_NEW set, hence the inode is locked, also
1460 *    i_count is set to 1, so it is not going to go away
1461 *
1462 * Return 0 on success and -errno on error.  In the error case, the inode will
1463 * have had make_bad_inode() executed on it.
1464 */
1465static int ntfs_read_locked_index_inode(struct inode *base_vi, struct inode *vi)
1466{
1467	loff_t bvi_size;
1468	ntfs_volume *vol = NTFS_SB(vi->i_sb);
1469	ntfs_inode *ni, *base_ni, *bni;
1470	struct inode *bvi;
1471	MFT_RECORD *m;
1472	ATTR_RECORD *a;
1473	ntfs_attr_search_ctx *ctx;
1474	INDEX_ROOT *ir;
1475	u8 *ir_end, *index_end;
1476	int err = 0;
1477
1478	ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
1479	ntfs_init_big_inode(vi);
1480	ni	= NTFS_I(vi);
1481	base_ni = NTFS_I(base_vi);
1482	/* Just mirror the values from the base inode. */
1483	vi->i_uid	= base_vi->i_uid;
1484	vi->i_gid	= base_vi->i_gid;
1485	set_nlink(vi, base_vi->i_nlink);
1486	vi->i_mtime	= base_vi->i_mtime;
1487	vi->i_ctime	= base_vi->i_ctime;
1488	vi->i_atime	= base_vi->i_atime;
1489	vi->i_generation = ni->seq_no = base_ni->seq_no;
1490	/* Set inode type to zero but preserve permissions. */
1491	vi->i_mode	= base_vi->i_mode & ~S_IFMT;
1492	/* Map the mft record for the base inode. */
1493	m = map_mft_record(base_ni);
1494	if (IS_ERR(m)) {
1495		err = PTR_ERR(m);
1496		goto err_out;
1497	}
1498	ctx = ntfs_attr_get_search_ctx(base_ni, m);
1499	if (!ctx) {
1500		err = -ENOMEM;
1501		goto unm_err_out;
1502	}
1503	/* Find the index root attribute. */
1504	err = ntfs_attr_lookup(AT_INDEX_ROOT, ni->name, ni->name_len,
1505			CASE_SENSITIVE, 0, NULL, 0, ctx);
1506	if (unlikely(err)) {
1507		if (err == -ENOENT)
1508			ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
1509					"missing.");
1510		goto unm_err_out;
1511	}
1512	a = ctx->attr;
1513	/* Set up the state. */
1514	if (unlikely(a->non_resident)) {
1515		ntfs_error(vol->sb, "$INDEX_ROOT attribute is not resident.");
1516		goto unm_err_out;
1517	}
1518	/* Ensure the attribute name is placed before the value. */
1519	if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1520			le16_to_cpu(a->data.resident.value_offset)))) {
1521		ntfs_error(vol->sb, "$INDEX_ROOT attribute name is placed "
1522				"after the attribute value.");
1523		goto unm_err_out;
1524	}
1525	/*
1526	 * Compressed/encrypted/sparse index root is not allowed, except for
1527	 * directories of course but those are not dealt with here.
1528	 */
1529	if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_ENCRYPTED |
1530			ATTR_IS_SPARSE)) {
1531		ntfs_error(vi->i_sb, "Found compressed/encrypted/sparse index "
1532				"root attribute.");
1533		goto unm_err_out;
1534	}
1535	ir = (INDEX_ROOT*)((u8*)a + le16_to_cpu(a->data.resident.value_offset));
1536	ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
1537	if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
1538		ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is corrupt.");
1539		goto unm_err_out;
1540	}
1541	index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length);
1542	if (index_end > ir_end) {
1543		ntfs_error(vi->i_sb, "Index is corrupt.");
1544		goto unm_err_out;
1545	}
1546	if (ir->type) {
1547		ntfs_error(vi->i_sb, "Index type is not 0 (type is 0x%x).",
1548				le32_to_cpu(ir->type));
1549		goto unm_err_out;
1550	}
1551	ni->itype.index.collation_rule = ir->collation_rule;
1552	ntfs_debug("Index collation rule is 0x%x.",
1553			le32_to_cpu(ir->collation_rule));
1554	ni->itype.index.block_size = le32_to_cpu(ir->index_block_size);
1555	if (!is_power_of_2(ni->itype.index.block_size)) {
1556		ntfs_error(vi->i_sb, "Index block size (%u) is not a power of "
1557				"two.", ni->itype.index.block_size);
1558		goto unm_err_out;
1559	}
1560	if (ni->itype.index.block_size > PAGE_SIZE) {
1561		ntfs_error(vi->i_sb, "Index block size (%u) > PAGE_SIZE "
1562				"(%ld) is not supported.  Sorry.",
1563				ni->itype.index.block_size, PAGE_SIZE);
1564		err = -EOPNOTSUPP;
1565		goto unm_err_out;
1566	}
1567	if (ni->itype.index.block_size < NTFS_BLOCK_SIZE) {
1568		ntfs_error(vi->i_sb, "Index block size (%u) < NTFS_BLOCK_SIZE "
1569				"(%i) is not supported.  Sorry.",
1570				ni->itype.index.block_size, NTFS_BLOCK_SIZE);
1571		err = -EOPNOTSUPP;
1572		goto unm_err_out;
1573	}
1574	ni->itype.index.block_size_bits = ffs(ni->itype.index.block_size) - 1;
1575	/* Determine the size of a vcn in the index. */
1576	if (vol->cluster_size <= ni->itype.index.block_size) {
1577		ni->itype.index.vcn_size = vol->cluster_size;
1578		ni->itype.index.vcn_size_bits = vol->cluster_size_bits;
1579	} else {
1580		ni->itype.index.vcn_size = vol->sector_size;
1581		ni->itype.index.vcn_size_bits = vol->sector_size_bits;
1582	}
1583	/* Check for presence of index allocation attribute. */
1584	if (!(ir->index.flags & LARGE_INDEX)) {
1585		/* No index allocation. */
1586		vi->i_size = ni->initialized_size = ni->allocated_size = 0;
1587		/* We are done with the mft record, so we release it. */
1588		ntfs_attr_put_search_ctx(ctx);
1589		unmap_mft_record(base_ni);
1590		m = NULL;
1591		ctx = NULL;
1592		goto skip_large_index_stuff;
1593	} /* LARGE_INDEX:  Index allocation present.  Setup state. */
1594	NInoSetIndexAllocPresent(ni);
1595	/* Find index allocation attribute. */
1596	ntfs_attr_reinit_search_ctx(ctx);
1597	err = ntfs_attr_lookup(AT_INDEX_ALLOCATION, ni->name, ni->name_len,
1598			CASE_SENSITIVE, 0, NULL, 0, ctx);
1599	if (unlikely(err)) {
1600		if (err == -ENOENT)
1601			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1602					"not present but $INDEX_ROOT "
1603					"indicated it is.");
1604		else
1605			ntfs_error(vi->i_sb, "Failed to lookup "
1606					"$INDEX_ALLOCATION attribute.");
1607		goto unm_err_out;
1608	}
1609	a = ctx->attr;
1610	if (!a->non_resident) {
1611		ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1612				"resident.");
1613		goto unm_err_out;
1614	}
1615	/*
1616	 * Ensure the attribute name is placed before the mapping pairs array.
1617	 */
1618	if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1619			le16_to_cpu(
1620			a->data.non_resident.mapping_pairs_offset)))) {
1621		ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name is "
1622				"placed after the mapping pairs array.");
1623		goto unm_err_out;
1624	}
1625	if (a->flags & ATTR_IS_ENCRYPTED) {
1626		ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1627				"encrypted.");
1628		goto unm_err_out;
1629	}
1630	if (a->flags & ATTR_IS_SPARSE) {
1631		ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is sparse.");
1632		goto unm_err_out;
1633	}
1634	if (a->flags & ATTR_COMPRESSION_MASK) {
1635		ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1636				"compressed.");
1637		goto unm_err_out;
1638	}
1639	if (a->data.non_resident.lowest_vcn) {
1640		ntfs_error(vi->i_sb, "First extent of $INDEX_ALLOCATION "
1641				"attribute has non zero lowest_vcn.");
1642		goto unm_err_out;
1643	}
1644	vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
1645	ni->initialized_size = sle64_to_cpu(
1646			a->data.non_resident.initialized_size);
1647	ni->allocated_size = sle64_to_cpu(a->data.non_resident.allocated_size);
1648	/*
1649	 * We are done with the mft record, so we release it.  Otherwise
1650	 * we would deadlock in ntfs_attr_iget().
1651	 */
1652	ntfs_attr_put_search_ctx(ctx);
1653	unmap_mft_record(base_ni);
1654	m = NULL;
1655	ctx = NULL;
1656	/* Get the index bitmap attribute inode. */
1657	bvi = ntfs_attr_iget(base_vi, AT_BITMAP, ni->name, ni->name_len);
1658	if (IS_ERR(bvi)) {
1659		ntfs_error(vi->i_sb, "Failed to get bitmap attribute.");
1660		err = PTR_ERR(bvi);
1661		goto unm_err_out;
1662	}
1663	bni = NTFS_I(bvi);
1664	if (NInoCompressed(bni) || NInoEncrypted(bni) ||
1665			NInoSparse(bni)) {
1666		ntfs_error(vi->i_sb, "$BITMAP attribute is compressed and/or "
1667				"encrypted and/or sparse.");
1668		goto iput_unm_err_out;
1669	}
1670	/* Consistency check bitmap size vs. index allocation size. */
1671	bvi_size = i_size_read(bvi);
1672	if ((bvi_size << 3) < (vi->i_size >> ni->itype.index.block_size_bits)) {
1673		ntfs_error(vi->i_sb, "Index bitmap too small (0x%llx) for "
1674				"index allocation (0x%llx).", bvi_size << 3,
1675				vi->i_size);
1676		goto iput_unm_err_out;
1677	}
1678	iput(bvi);
1679skip_large_index_stuff:
1680	/* Setup the operations for this index inode. */
1681	vi->i_mapping->a_ops = &ntfs_mst_aops;
1682	vi->i_blocks = ni->allocated_size >> 9;
1683	/*
1684	 * Make sure the base inode doesn't go away and attach it to the
1685	 * index inode.
1686	 */
1687	igrab(base_vi);
1688	ni->ext.base_ntfs_ino = base_ni;
1689	ni->nr_extents = -1;
1690
1691	ntfs_debug("Done.");
1692	return 0;
1693iput_unm_err_out:
1694	iput(bvi);
1695unm_err_out:
1696	if (!err)
1697		err = -EIO;
1698	if (ctx)
1699		ntfs_attr_put_search_ctx(ctx);
1700	if (m)
1701		unmap_mft_record(base_ni);
1702err_out:
1703	ntfs_error(vi->i_sb, "Failed with error code %i while reading index "
1704			"inode (mft_no 0x%lx, name_len %i.", err, vi->i_ino,
1705			ni->name_len);
1706	make_bad_inode(vi);
1707	if (err != -EOPNOTSUPP && err != -ENOMEM)
1708		NVolSetErrors(vol);
1709	return err;
1710}
1711
1712/*
1713 * The MFT inode has special locking, so teach the lock validator
1714 * about this by splitting off the locking rules of the MFT from
1715 * the locking rules of other inodes. The MFT inode can never be
1716 * accessed from the VFS side (or even internally), only by the
1717 * map_mft functions.
1718 */
1719static struct lock_class_key mft_ni_runlist_lock_key, mft_ni_mrec_lock_key;
1720
1721/**
1722 * ntfs_read_inode_mount - special read_inode for mount time use only
1723 * @vi:		inode to read
1724 *
1725 * Read inode FILE_MFT at mount time, only called with super_block lock
1726 * held from within the read_super() code path.
1727 *
1728 * This function exists because when it is called the page cache for $MFT/$DATA
1729 * is not initialized and hence we cannot get at the contents of mft records
1730 * by calling map_mft_record*().
1731 *
1732 * Further it needs to cope with the circular references problem, i.e. cannot
1733 * load any attributes other than $ATTRIBUTE_LIST until $DATA is loaded, because
1734 * we do not know where the other extent mft records are yet and again, because
1735 * we cannot call map_mft_record*() yet.  Obviously this applies only when an
1736 * attribute list is actually present in $MFT inode.
1737 *
1738 * We solve these problems by starting with the $DATA attribute before anything
1739 * else and iterating using ntfs_attr_lookup($DATA) over all extents.  As each
1740 * extent is found, we ntfs_mapping_pairs_decompress() including the implied
1741 * ntfs_runlists_merge().  Each step of the iteration necessarily provides
1742 * sufficient information for the next step to complete.
1743 *
1744 * This should work but there are two possible pit falls (see inline comments
1745 * below), but only time will tell if they are real pits or just smoke...
1746 */
1747int ntfs_read_inode_mount(struct inode *vi)
1748{
1749	VCN next_vcn, last_vcn, highest_vcn;
1750	s64 block;
1751	struct super_block *sb = vi->i_sb;
1752	ntfs_volume *vol = NTFS_SB(sb);
1753	struct buffer_head *bh;
1754	ntfs_inode *ni;
1755	MFT_RECORD *m = NULL;
1756	ATTR_RECORD *a;
1757	ntfs_attr_search_ctx *ctx;
1758	unsigned int i, nr_blocks;
1759	int err;
1760
1761	ntfs_debug("Entering.");
1762
1763	/* Initialize the ntfs specific part of @vi. */
1764	ntfs_init_big_inode(vi);
1765
1766	ni = NTFS_I(vi);
1767
1768	/* Setup the data attribute. It is special as it is mst protected. */
1769	NInoSetNonResident(ni);
1770	NInoSetMstProtected(ni);
1771	NInoSetSparseDisabled(ni);
1772	ni->type = AT_DATA;
1773	ni->name = NULL;
1774	ni->name_len = 0;
1775	/*
1776	 * This sets up our little cheat allowing us to reuse the async read io
1777	 * completion handler for directories.
1778	 */
1779	ni->itype.index.block_size = vol->mft_record_size;
1780	ni->itype.index.block_size_bits = vol->mft_record_size_bits;
1781
1782	/* Very important! Needed to be able to call map_mft_record*(). */
1783	vol->mft_ino = vi;
1784
1785	/* Allocate enough memory to read the first mft record. */
1786	if (vol->mft_record_size > 64 * 1024) {
1787		ntfs_error(sb, "Unsupported mft record size %i (max 64kiB).",
1788				vol->mft_record_size);
1789		goto err_out;
1790	}
1791	i = vol->mft_record_size;
1792	if (i < sb->s_blocksize)
1793		i = sb->s_blocksize;
1794	m = (MFT_RECORD*)ntfs_malloc_nofs(i);
1795	if (!m) {
1796		ntfs_error(sb, "Failed to allocate buffer for $MFT record 0.");
1797		goto err_out;
1798	}
1799
1800	/* Determine the first block of the $MFT/$DATA attribute. */
1801	block = vol->mft_lcn << vol->cluster_size_bits >>
1802			sb->s_blocksize_bits;
1803	nr_blocks = vol->mft_record_size >> sb->s_blocksize_bits;
1804	if (!nr_blocks)
1805		nr_blocks = 1;
1806
1807	/* Load $MFT/$DATA's first mft record. */
1808	for (i = 0; i < nr_blocks; i++) {
1809		bh = sb_bread(sb, block++);
1810		if (!bh) {
1811			ntfs_error(sb, "Device read failed.");
1812			goto err_out;
1813		}
1814		memcpy((char*)m + (i << sb->s_blocksize_bits), bh->b_data,
1815				sb->s_blocksize);
1816		brelse(bh);
1817	}
1818
1819	if (le32_to_cpu(m->bytes_allocated) != vol->mft_record_size) {
1820		ntfs_error(sb, "Incorrect mft record size %u in superblock, should be %u.",
1821				le32_to_cpu(m->bytes_allocated), vol->mft_record_size);
1822		goto err_out;
1823	}
1824
1825	/* Apply the mst fixups. */
1826	if (post_read_mst_fixup((NTFS_RECORD*)m, vol->mft_record_size)) {
1827		/* FIXME: Try to use the $MFTMirr now. */
1828		ntfs_error(sb, "MST fixup failed. $MFT is corrupt.");
1829		goto err_out;
1830	}
1831
1832	/* Sanity check offset to the first attribute */
1833	if (le16_to_cpu(m->attrs_offset) >= le32_to_cpu(m->bytes_allocated)) {
1834		ntfs_error(sb, "Incorrect mft offset to the first attribute %u in superblock.",
1835			       le16_to_cpu(m->attrs_offset));
1836		goto err_out;
1837	}
1838
1839	/* Need this to sanity check attribute list references to $MFT. */
1840	vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);
1841
1842	/* Provides read_folio() for map_mft_record(). */
1843	vi->i_mapping->a_ops = &ntfs_mst_aops;
1844
1845	ctx = ntfs_attr_get_search_ctx(ni, m);
1846	if (!ctx) {
1847		err = -ENOMEM;
1848		goto err_out;
1849	}
1850
1851	/* Find the attribute list attribute if present. */
1852	err = ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, 0, 0, NULL, 0, ctx);
1853	if (err) {
1854		if (unlikely(err != -ENOENT)) {
1855			ntfs_error(sb, "Failed to lookup attribute list "
1856					"attribute. You should run chkdsk.");
1857			goto put_err_out;
1858		}
1859	} else /* if (!err) */ {
1860		ATTR_LIST_ENTRY *al_entry, *next_al_entry;
1861		u8 *al_end;
1862		static const char *es = "  Not allowed.  $MFT is corrupt.  "
1863				"You should run chkdsk.";
1864
1865		ntfs_debug("Attribute list attribute found in $MFT.");
1866		NInoSetAttrList(ni);
1867		a = ctx->attr;
1868		if (a->flags & ATTR_COMPRESSION_MASK) {
1869			ntfs_error(sb, "Attribute list attribute is "
1870					"compressed.%s", es);
1871			goto put_err_out;
1872		}
1873		if (a->flags & ATTR_IS_ENCRYPTED ||
1874				a->flags & ATTR_IS_SPARSE) {
1875			if (a->non_resident) {
1876				ntfs_error(sb, "Non-resident attribute list "
1877						"attribute is encrypted/"
1878						"sparse.%s", es);
1879				goto put_err_out;
1880			}
1881			ntfs_warning(sb, "Resident attribute list attribute "
1882					"in $MFT system file is marked "
1883					"encrypted/sparse which is not true.  "
1884					"However, Windows allows this and "
1885					"chkdsk does not detect or correct it "
1886					"so we will just ignore the invalid "
1887					"flags and pretend they are not set.");
1888		}
1889		/* Now allocate memory for the attribute list. */
1890		ni->attr_list_size = (u32)ntfs_attr_size(a);
1891		if (!ni->attr_list_size) {
1892			ntfs_error(sb, "Attr_list_size is zero");
1893			goto put_err_out;
1894		}
1895		ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
1896		if (!ni->attr_list) {
1897			ntfs_error(sb, "Not enough memory to allocate buffer "
1898					"for attribute list.");
1899			goto put_err_out;
1900		}
1901		if (a->non_resident) {
1902			NInoSetAttrListNonResident(ni);
1903			if (a->data.non_resident.lowest_vcn) {
1904				ntfs_error(sb, "Attribute list has non zero "
1905						"lowest_vcn. $MFT is corrupt. "
1906						"You should run chkdsk.");
1907				goto put_err_out;
1908			}
1909			/* Setup the runlist. */
1910			ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
1911					a, NULL);
1912			if (IS_ERR(ni->attr_list_rl.rl)) {
1913				err = PTR_ERR(ni->attr_list_rl.rl);
1914				ni->attr_list_rl.rl = NULL;
1915				ntfs_error(sb, "Mapping pairs decompression "
1916						"failed with error code %i.",
1917						-err);
1918				goto put_err_out;
1919			}
1920			/* Now load the attribute list. */
1921			if ((err = load_attribute_list(vol, &ni->attr_list_rl,
1922					ni->attr_list, ni->attr_list_size,
1923					sle64_to_cpu(a->data.
1924					non_resident.initialized_size)))) {
1925				ntfs_error(sb, "Failed to load attribute list "
1926						"attribute with error code %i.",
1927						-err);
1928				goto put_err_out;
1929			}
1930		} else /* if (!ctx.attr->non_resident) */ {
1931			if ((u8*)a + le16_to_cpu(
1932					a->data.resident.value_offset) +
1933					le32_to_cpu(
1934					a->data.resident.value_length) >
1935					(u8*)ctx->mrec + vol->mft_record_size) {
1936				ntfs_error(sb, "Corrupt attribute list "
1937						"attribute.");
1938				goto put_err_out;
1939			}
1940			/* Now copy the attribute list. */
1941			memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
1942					a->data.resident.value_offset),
1943					le32_to_cpu(
1944					a->data.resident.value_length));
1945		}
1946		/* The attribute list is now setup in memory. */
1947		/*
1948		 * FIXME: I don't know if this case is actually possible.
1949		 * According to logic it is not possible but I have seen too
1950		 * many weird things in MS software to rely on logic... Thus we
1951		 * perform a manual search and make sure the first $MFT/$DATA
1952		 * extent is in the base inode. If it is not we abort with an
1953		 * error and if we ever see a report of this error we will need
1954		 * to do some magic in order to have the necessary mft record
1955		 * loaded and in the right place in the page cache. But
1956		 * hopefully logic will prevail and this never happens...
1957		 */
1958		al_entry = (ATTR_LIST_ENTRY*)ni->attr_list;
1959		al_end = (u8*)al_entry + ni->attr_list_size;
1960		for (;; al_entry = next_al_entry) {
1961			/* Out of bounds check. */
1962			if ((u8*)al_entry < ni->attr_list ||
1963					(u8*)al_entry > al_end)
1964				goto em_put_err_out;
1965			/* Catch the end of the attribute list. */
1966			if ((u8*)al_entry == al_end)
1967				goto em_put_err_out;
1968			if (!al_entry->length)
1969				goto em_put_err_out;
1970			if ((u8*)al_entry + 6 > al_end || (u8*)al_entry +
1971					le16_to_cpu(al_entry->length) > al_end)
1972				goto em_put_err_out;
1973			next_al_entry = (ATTR_LIST_ENTRY*)((u8*)al_entry +
1974					le16_to_cpu(al_entry->length));
1975			if (le32_to_cpu(al_entry->type) > le32_to_cpu(AT_DATA))
1976				goto em_put_err_out;
1977			if (AT_DATA != al_entry->type)
1978				continue;
1979			/* We want an unnamed attribute. */
1980			if (al_entry->name_length)
1981				goto em_put_err_out;
1982			/* Want the first entry, i.e. lowest_vcn == 0. */
1983			if (al_entry->lowest_vcn)
1984				goto em_put_err_out;
1985			/* First entry has to be in the base mft record. */
1986			if (MREF_LE(al_entry->mft_reference) != vi->i_ino) {
1987				/* MFT references do not match, logic fails. */
1988				ntfs_error(sb, "BUG: The first $DATA extent "
1989						"of $MFT is not in the base "
1990						"mft record. Please report "
1991						"you saw this message to "
1992						"linux-ntfs-dev@lists."
1993						"sourceforge.net");
1994				goto put_err_out;
1995			} else {
1996				/* Sequence numbers must match. */
1997				if (MSEQNO_LE(al_entry->mft_reference) !=
1998						ni->seq_no)
1999					goto em_put_err_out;
2000				/* Got it. All is ok. We can stop now. */
2001				break;
2002			}
2003		}
2004	}
2005
2006	ntfs_attr_reinit_search_ctx(ctx);
2007
2008	/* Now load all attribute extents. */
2009	a = NULL;
2010	next_vcn = last_vcn = highest_vcn = 0;
2011	while (!(err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, next_vcn, NULL, 0,
2012			ctx))) {
2013		runlist_element *nrl;
2014
2015		/* Cache the current attribute. */
2016		a = ctx->attr;
2017		/* $MFT must be non-resident. */
2018		if (!a->non_resident) {
2019			ntfs_error(sb, "$MFT must be non-resident but a "
2020					"resident extent was found. $MFT is "
2021					"corrupt. Run chkdsk.");
2022			goto put_err_out;
2023		}
2024		/* $MFT must be uncompressed and unencrypted. */
2025		if (a->flags & ATTR_COMPRESSION_MASK ||
2026				a->flags & ATTR_IS_ENCRYPTED ||
2027				a->flags & ATTR_IS_SPARSE) {
2028			ntfs_error(sb, "$MFT must be uncompressed, "
2029					"non-sparse, and unencrypted but a "
2030					"compressed/sparse/encrypted extent "
2031					"was found. $MFT is corrupt. Run "
2032					"chkdsk.");
2033			goto put_err_out;
2034		}
2035		/*
2036		 * Decompress the mapping pairs array of this extent and merge
2037		 * the result into the existing runlist. No need for locking
2038		 * as we have exclusive access to the inode at this time and we
2039		 * are a mount in progress task, too.
2040		 */
2041		nrl = ntfs_mapping_pairs_decompress(vol, a, ni->runlist.rl);
2042		if (IS_ERR(nrl)) {
2043			ntfs_error(sb, "ntfs_mapping_pairs_decompress() "
2044					"failed with error code %ld.  $MFT is "
2045					"corrupt.", PTR_ERR(nrl));
2046			goto put_err_out;
2047		}
2048		ni->runlist.rl = nrl;
2049
2050		/* Are we in the first extent? */
2051		if (!next_vcn) {
2052			if (a->data.non_resident.lowest_vcn) {
2053				ntfs_error(sb, "First extent of $DATA "
2054						"attribute has non zero "
2055						"lowest_vcn. $MFT is corrupt. "
2056						"You should run chkdsk.");
2057				goto put_err_out;
2058			}
2059			/* Get the last vcn in the $DATA attribute. */
2060			last_vcn = sle64_to_cpu(
2061					a->data.non_resident.allocated_size)
2062					>> vol->cluster_size_bits;
2063			/* Fill in the inode size. */
2064			vi->i_size = sle64_to_cpu(
2065					a->data.non_resident.data_size);
2066			ni->initialized_size = sle64_to_cpu(
2067					a->data.non_resident.initialized_size);
2068			ni->allocated_size = sle64_to_cpu(
2069					a->data.non_resident.allocated_size);
2070			/*
2071			 * Verify the number of mft records does not exceed
2072			 * 2^32 - 1.
2073			 */
2074			if ((vi->i_size >> vol->mft_record_size_bits) >=
2075					(1ULL << 32)) {
2076				ntfs_error(sb, "$MFT is too big! Aborting.");
2077				goto put_err_out;
2078			}
2079			/*
2080			 * We have got the first extent of the runlist for
2081			 * $MFT which means it is now relatively safe to call
2082			 * the normal ntfs_read_inode() function.
2083			 * Complete reading the inode, this will actually
2084			 * re-read the mft record for $MFT, this time entering
2085			 * it into the page cache with which we complete the
2086			 * kick start of the volume. It should be safe to do
2087			 * this now as the first extent of $MFT/$DATA is
2088			 * already known and we would hope that we don't need
2089			 * further extents in order to find the other
2090			 * attributes belonging to $MFT. Only time will tell if
2091			 * this is really the case. If not we will have to play
2092			 * magic at this point, possibly duplicating a lot of
2093			 * ntfs_read_inode() at this point. We will need to
2094			 * ensure we do enough of its work to be able to call
2095			 * ntfs_read_inode() on extents of $MFT/$DATA. But lets
2096			 * hope this never happens...
2097			 */
2098			ntfs_read_locked_inode(vi);
2099			if (is_bad_inode(vi)) {
2100				ntfs_error(sb, "ntfs_read_inode() of $MFT "
2101						"failed. BUG or corrupt $MFT. "
2102						"Run chkdsk and if no errors "
2103						"are found, please report you "
2104						"saw this message to "
2105						"linux-ntfs-dev@lists."
2106						"sourceforge.net");
2107				ntfs_attr_put_search_ctx(ctx);
2108				/* Revert to the safe super operations. */
2109				ntfs_free(m);
2110				return -1;
2111			}
2112			/*
2113			 * Re-initialize some specifics about $MFT's inode as
2114			 * ntfs_read_inode() will have set up the default ones.
2115			 */
2116			/* Set uid and gid to root. */
2117			vi->i_uid = GLOBAL_ROOT_UID;
2118			vi->i_gid = GLOBAL_ROOT_GID;
2119			/* Regular file. No access for anyone. */
2120			vi->i_mode = S_IFREG;
2121			/* No VFS initiated operations allowed for $MFT. */
2122			vi->i_op = &ntfs_empty_inode_ops;
2123			vi->i_fop = &ntfs_empty_file_ops;
2124		}
2125
2126		/* Get the lowest vcn for the next extent. */
2127		highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
2128		next_vcn = highest_vcn + 1;
2129
2130		/* Only one extent or error, which we catch below. */
2131		if (next_vcn <= 0)
2132			break;
2133
2134		/* Avoid endless loops due to corruption. */
2135		if (next_vcn < sle64_to_cpu(
2136				a->data.non_resident.lowest_vcn)) {
2137			ntfs_error(sb, "$MFT has corrupt attribute list "
2138					"attribute. Run chkdsk.");
2139			goto put_err_out;
2140		}
2141	}
2142	if (err != -ENOENT) {
2143		ntfs_error(sb, "Failed to lookup $MFT/$DATA attribute extent. "
2144				"$MFT is corrupt. Run chkdsk.");
2145		goto put_err_out;
2146	}
2147	if (!a) {
2148		ntfs_error(sb, "$MFT/$DATA attribute not found. $MFT is "
2149				"corrupt. Run chkdsk.");
2150		goto put_err_out;
2151	}
2152	if (highest_vcn && highest_vcn != last_vcn - 1) {
2153		ntfs_error(sb, "Failed to load the complete runlist for "
2154				"$MFT/$DATA. Driver bug or corrupt $MFT. "
2155				"Run chkdsk.");
2156		ntfs_debug("highest_vcn = 0x%llx, last_vcn - 1 = 0x%llx",
2157				(unsigned long long)highest_vcn,
2158				(unsigned long long)last_vcn - 1);
2159		goto put_err_out;
2160	}
2161	ntfs_attr_put_search_ctx(ctx);
2162	ntfs_debug("Done.");
2163	ntfs_free(m);
2164
2165	/*
2166	 * Split the locking rules of the MFT inode from the
2167	 * locking rules of other inodes:
2168	 */
2169	lockdep_set_class(&ni->runlist.lock, &mft_ni_runlist_lock_key);
2170	lockdep_set_class(&ni->mrec_lock, &mft_ni_mrec_lock_key);
2171
2172	return 0;
2173
2174em_put_err_out:
2175	ntfs_error(sb, "Couldn't find first extent of $DATA attribute in "
2176			"attribute list. $MFT is corrupt. Run chkdsk.");
2177put_err_out:
2178	ntfs_attr_put_search_ctx(ctx);
2179err_out:
2180	ntfs_error(sb, "Failed. Marking inode as bad.");
2181	make_bad_inode(vi);
2182	ntfs_free(m);
2183	return -1;
2184}
2185
2186static void __ntfs_clear_inode(ntfs_inode *ni)
2187{
2188	/* Free all alocated memory. */
2189	down_write(&ni->runlist.lock);
2190	if (ni->runlist.rl) {
2191		ntfs_free(ni->runlist.rl);
2192		ni->runlist.rl = NULL;
2193	}
2194	up_write(&ni->runlist.lock);
2195
2196	if (ni->attr_list) {
2197		ntfs_free(ni->attr_list);
2198		ni->attr_list = NULL;
2199	}
2200
2201	down_write(&ni->attr_list_rl.lock);
2202	if (ni->attr_list_rl.rl) {
2203		ntfs_free(ni->attr_list_rl.rl);
2204		ni->attr_list_rl.rl = NULL;
2205	}
2206	up_write(&ni->attr_list_rl.lock);
2207
2208	if (ni->name_len && ni->name != I30) {
2209		/* Catch bugs... */
2210		BUG_ON(!ni->name);
2211		kfree(ni->name);
2212	}
2213}
2214
2215void ntfs_clear_extent_inode(ntfs_inode *ni)
2216{
2217	ntfs_debug("Entering for inode 0x%lx.", ni->mft_no);
2218
2219	BUG_ON(NInoAttr(ni));
2220	BUG_ON(ni->nr_extents != -1);
2221
2222#ifdef NTFS_RW
2223	if (NInoDirty(ni)) {
2224		if (!is_bad_inode(VFS_I(ni->ext.base_ntfs_ino)))
2225			ntfs_error(ni->vol->sb, "Clearing dirty extent inode!  "
2226					"Losing data!  This is a BUG!!!");
2227		// FIXME:  Do something!!!
2228	}
2229#endif /* NTFS_RW */
2230
2231	__ntfs_clear_inode(ni);
2232
2233	/* Bye, bye... */
2234	ntfs_destroy_extent_inode(ni);
2235}
2236
2237/**
2238 * ntfs_evict_big_inode - clean up the ntfs specific part of an inode
2239 * @vi:		vfs inode pending annihilation
2240 *
2241 * When the VFS is going to remove an inode from memory, ntfs_clear_big_inode()
2242 * is called, which deallocates all memory belonging to the NTFS specific part
2243 * of the inode and returns.
2244 *
2245 * If the MFT record is dirty, we commit it before doing anything else.
2246 */
2247void ntfs_evict_big_inode(struct inode *vi)
2248{
2249	ntfs_inode *ni = NTFS_I(vi);
2250
2251	truncate_inode_pages_final(&vi->i_data);
2252	clear_inode(vi);
2253
2254#ifdef NTFS_RW
2255	if (NInoDirty(ni)) {
2256		bool was_bad = (is_bad_inode(vi));
2257
2258		/* Committing the inode also commits all extent inodes. */
2259		ntfs_commit_inode(vi);
2260
2261		if (!was_bad && (is_bad_inode(vi) || NInoDirty(ni))) {
2262			ntfs_error(vi->i_sb, "Failed to commit dirty inode "
2263					"0x%lx.  Losing data!", vi->i_ino);
2264			// FIXME:  Do something!!!
2265		}
2266	}
2267#endif /* NTFS_RW */
2268
2269	/* No need to lock at this stage as no one else has a reference. */
2270	if (ni->nr_extents > 0) {
2271		int i;
2272
2273		for (i = 0; i < ni->nr_extents; i++)
2274			ntfs_clear_extent_inode(ni->ext.extent_ntfs_inos[i]);
2275		kfree(ni->ext.extent_ntfs_inos);
2276	}
2277
2278	__ntfs_clear_inode(ni);
2279
2280	if (NInoAttr(ni)) {
2281		/* Release the base inode if we are holding it. */
2282		if (ni->nr_extents == -1) {
2283			iput(VFS_I(ni->ext.base_ntfs_ino));
2284			ni->nr_extents = 0;
2285			ni->ext.base_ntfs_ino = NULL;
2286		}
2287	}
2288	BUG_ON(ni->page);
2289	if (!atomic_dec_and_test(&ni->count))
2290		BUG();
2291	return;
2292}
2293
2294/**
2295 * ntfs_show_options - show mount options in /proc/mounts
2296 * @sf:		seq_file in which to write our mount options
2297 * @root:	root of the mounted tree whose mount options to display
2298 *
2299 * Called by the VFS once for each mounted ntfs volume when someone reads
2300 * /proc/mounts in order to display the NTFS specific mount options of each
2301 * mount. The mount options of fs specified by @root are written to the seq file
2302 * @sf and success is returned.
2303 */
2304int ntfs_show_options(struct seq_file *sf, struct dentry *root)
2305{
2306	ntfs_volume *vol = NTFS_SB(root->d_sb);
2307	int i;
2308
2309	seq_printf(sf, ",uid=%i", from_kuid_munged(&init_user_ns, vol->uid));
2310	seq_printf(sf, ",gid=%i", from_kgid_munged(&init_user_ns, vol->gid));
2311	if (vol->fmask == vol->dmask)
2312		seq_printf(sf, ",umask=0%o", vol->fmask);
2313	else {
2314		seq_printf(sf, ",fmask=0%o", vol->fmask);
2315		seq_printf(sf, ",dmask=0%o", vol->dmask);
2316	}
2317	seq_printf(sf, ",nls=%s", vol->nls_map->charset);
2318	if (NVolCaseSensitive(vol))
2319		seq_printf(sf, ",case_sensitive");
2320	if (NVolShowSystemFiles(vol))
2321		seq_printf(sf, ",show_sys_files");
2322	if (!NVolSparseEnabled(vol))
2323		seq_printf(sf, ",disable_sparse");
2324	for (i = 0; on_errors_arr[i].val; i++) {
2325		if (on_errors_arr[i].val & vol->on_errors)
2326			seq_printf(sf, ",errors=%s", on_errors_arr[i].str);
2327	}
2328	seq_printf(sf, ",mft_zone_multiplier=%i", vol->mft_zone_multiplier);
2329	return 0;
2330}
2331
2332#ifdef NTFS_RW
2333
2334static const char *es = "  Leaving inconsistent metadata.  Unmount and run "
2335		"chkdsk.";
2336
2337/**
2338 * ntfs_truncate - called when the i_size of an ntfs inode is changed
2339 * @vi:		inode for which the i_size was changed
2340 *
2341 * We only support i_size changes for normal files at present, i.e. not
2342 * compressed and not encrypted.  This is enforced in ntfs_setattr(), see
2343 * below.
2344 *
2345 * The kernel guarantees that @vi is a regular file (S_ISREG() is true) and
2346 * that the change is allowed.
2347 *
2348 * This implies for us that @vi is a file inode rather than a directory, index,
2349 * or attribute inode as well as that @vi is a base inode.
2350 *
2351 * Returns 0 on success or -errno on error.
2352 *
2353 * Called with ->i_mutex held.
2354 */
2355int ntfs_truncate(struct inode *vi)
2356{
2357	s64 new_size, old_size, nr_freed, new_alloc_size, old_alloc_size;
2358	VCN highest_vcn;
2359	unsigned long flags;
2360	ntfs_inode *base_ni, *ni = NTFS_I(vi);
2361	ntfs_volume *vol = ni->vol;
2362	ntfs_attr_search_ctx *ctx;
2363	MFT_RECORD *m;
2364	ATTR_RECORD *a;
2365	const char *te = "  Leaving file length out of sync with i_size.";
2366	int err, mp_size, size_change, alloc_change;
2367
2368	ntfs_debug("Entering for inode 0x%lx.", vi->i_ino);
2369	BUG_ON(NInoAttr(ni));
2370	BUG_ON(S_ISDIR(vi->i_mode));
2371	BUG_ON(NInoMstProtected(ni));
2372	BUG_ON(ni->nr_extents < 0);
2373retry_truncate:
2374	/*
2375	 * Lock the runlist for writing and map the mft record to ensure it is
2376	 * safe to mess with the attribute runlist and sizes.
2377	 */
2378	down_write(&ni->runlist.lock);
2379	if (!NInoAttr(ni))
2380		base_ni = ni;
2381	else
2382		base_ni = ni->ext.base_ntfs_ino;
2383	m = map_mft_record(base_ni);
2384	if (IS_ERR(m)) {
2385		err = PTR_ERR(m);
2386		ntfs_error(vi->i_sb, "Failed to map mft record for inode 0x%lx "
2387				"(error code %d).%s", vi->i_ino, err, te);
2388		ctx = NULL;
2389		m = NULL;
2390		goto old_bad_out;
2391	}
2392	ctx = ntfs_attr_get_search_ctx(base_ni, m);
2393	if (unlikely(!ctx)) {
2394		ntfs_error(vi->i_sb, "Failed to allocate a search context for "
2395				"inode 0x%lx (not enough memory).%s",
2396				vi->i_ino, te);
2397		err = -ENOMEM;
2398		goto old_bad_out;
2399	}
2400	err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
2401			CASE_SENSITIVE, 0, NULL, 0, ctx);
2402	if (unlikely(err)) {
2403		if (err == -ENOENT) {
2404			ntfs_error(vi->i_sb, "Open attribute is missing from "
2405					"mft record.  Inode 0x%lx is corrupt.  "
2406					"Run chkdsk.%s", vi->i_ino, te);
2407			err = -EIO;
2408		} else
2409			ntfs_error(vi->i_sb, "Failed to lookup attribute in "
2410					"inode 0x%lx (error code %d).%s",
2411					vi->i_ino, err, te);
2412		goto old_bad_out;
2413	}
2414	m = ctx->mrec;
2415	a = ctx->attr;
2416	/*
2417	 * The i_size of the vfs inode is the new size for the attribute value.
2418	 */
2419	new_size = i_size_read(vi);
2420	/* The current size of the attribute value is the old size. */
2421	old_size = ntfs_attr_size(a);
2422	/* Calculate the new allocated size. */
2423	if (NInoNonResident(ni))
2424		new_alloc_size = (new_size + vol->cluster_size - 1) &
2425				~(s64)vol->cluster_size_mask;
2426	else
2427		new_alloc_size = (new_size + 7) & ~7;
2428	/* The current allocated size is the old allocated size. */
2429	read_lock_irqsave(&ni->size_lock, flags);
2430	old_alloc_size = ni->allocated_size;
2431	read_unlock_irqrestore(&ni->size_lock, flags);
2432	/*
2433	 * The change in the file size.  This will be 0 if no change, >0 if the
2434	 * size is growing, and <0 if the size is shrinking.
2435	 */
2436	size_change = -1;
2437	if (new_size - old_size >= 0) {
2438		size_change = 1;
2439		if (new_size == old_size)
2440			size_change = 0;
2441	}
2442	/* As above for the allocated size. */
2443	alloc_change = -1;
2444	if (new_alloc_size - old_alloc_size >= 0) {
2445		alloc_change = 1;
2446		if (new_alloc_size == old_alloc_size)
2447			alloc_change = 0;
2448	}
2449	/*
2450	 * If neither the size nor the allocation are being changed there is
2451	 * nothing to do.
2452	 */
2453	if (!size_change && !alloc_change)
2454		goto unm_done;
2455	/* If the size is changing, check if new size is allowed in $AttrDef. */
2456	if (size_change) {
2457		err = ntfs_attr_size_bounds_check(vol, ni->type, new_size);
2458		if (unlikely(err)) {
2459			if (err == -ERANGE) {
2460				ntfs_error(vol->sb, "Truncate would cause the "
2461						"inode 0x%lx to %simum size "
2462						"for its attribute type "
2463						"(0x%x).  Aborting truncate.",
2464						vi->i_ino,
2465						new_size > old_size ? "exceed "
2466						"the max" : "go under the min",
2467						le32_to_cpu(ni->type));
2468				err = -EFBIG;
2469			} else {
2470				ntfs_error(vol->sb, "Inode 0x%lx has unknown "
2471						"attribute type 0x%x.  "
2472						"Aborting truncate.",
2473						vi->i_ino,
2474						le32_to_cpu(ni->type));
2475				err = -EIO;
2476			}
2477			/* Reset the vfs inode size to the old size. */
2478			i_size_write(vi, old_size);
2479			goto err_out;
2480		}
2481	}
2482	if (NInoCompressed(ni) || NInoEncrypted(ni)) {
2483		ntfs_warning(vi->i_sb, "Changes in inode size are not "
2484				"supported yet for %s files, ignoring.",
2485				NInoCompressed(ni) ? "compressed" :
2486				"encrypted");
2487		err = -EOPNOTSUPP;
2488		goto bad_out;
2489	}
2490	if (a->non_resident)
2491		goto do_non_resident_truncate;
2492	BUG_ON(NInoNonResident(ni));
2493	/* Resize the attribute record to best fit the new attribute size. */
2494	if (new_size < vol->mft_record_size &&
2495			!ntfs_resident_attr_value_resize(m, a, new_size)) {
2496		/* The resize succeeded! */
2497		flush_dcache_mft_record_page(ctx->ntfs_ino);
2498		mark_mft_record_dirty(ctx->ntfs_ino);
2499		write_lock_irqsave(&ni->size_lock, flags);
2500		/* Update the sizes in the ntfs inode and all is done. */
2501		ni->allocated_size = le32_to_cpu(a->length) -
2502				le16_to_cpu(a->data.resident.value_offset);
2503		/*
2504		 * Note ntfs_resident_attr_value_resize() has already done any
2505		 * necessary data clearing in the attribute record.  When the
2506		 * file is being shrunk vmtruncate() will already have cleared
2507		 * the top part of the last partial page, i.e. since this is
2508		 * the resident case this is the page with index 0.  However,
2509		 * when the file is being expanded, the page cache page data
2510		 * between the old data_size, i.e. old_size, and the new_size
2511		 * has not been zeroed.  Fortunately, we do not need to zero it
2512		 * either since on one hand it will either already be zero due
2513		 * to both read_folio and writepage clearing partial page data
2514		 * beyond i_size in which case there is nothing to do or in the
2515		 * case of the file being mmap()ped at the same time, POSIX
2516		 * specifies that the behaviour is unspecified thus we do not
2517		 * have to do anything.  This means that in our implementation
2518		 * in the rare case that the file is mmap()ped and a write
2519		 * occurred into the mmap()ped region just beyond the file size
2520		 * and writepage has not yet been called to write out the page
2521		 * (which would clear the area beyond the file size) and we now
2522		 * extend the file size to incorporate this dirty region
2523		 * outside the file size, a write of the page would result in
2524		 * this data being written to disk instead of being cleared.
2525		 * Given both POSIX and the Linux mmap(2) man page specify that
2526		 * this corner case is undefined, we choose to leave it like
2527		 * that as this is much simpler for us as we cannot lock the
2528		 * relevant page now since we are holding too many ntfs locks
2529		 * which would result in a lock reversal deadlock.
2530		 */
2531		ni->initialized_size = new_size;
2532		write_unlock_irqrestore(&ni->size_lock, flags);
2533		goto unm_done;
2534	}
2535	/* If the above resize failed, this must be an attribute extension. */
2536	BUG_ON(size_change < 0);
2537	/*
2538	 * We have to drop all the locks so we can call
2539	 * ntfs_attr_make_non_resident().  This could be optimised by try-
2540	 * locking the first page cache page and only if that fails dropping
2541	 * the locks, locking the page, and redoing all the locking and
2542	 * lookups.  While this would be a huge optimisation, it is not worth
2543	 * it as this is definitely a slow code path as it only ever can happen
2544	 * once for any given file.
2545	 */
2546	ntfs_attr_put_search_ctx(ctx);
2547	unmap_mft_record(base_ni);
2548	up_write(&ni->runlist.lock);
2549	/*
2550	 * Not enough space in the mft record, try to make the attribute
2551	 * non-resident and if successful restart the truncation process.
2552	 */
2553	err = ntfs_attr_make_non_resident(ni, old_size);
2554	if (likely(!err))
2555		goto retry_truncate;
2556	/*
2557	 * Could not make non-resident.  If this is due to this not being
2558	 * permitted for this attribute type or there not being enough space,
2559	 * try to make other attributes non-resident.  Otherwise fail.
2560	 */
2561	if (unlikely(err != -EPERM && err != -ENOSPC)) {
2562		ntfs_error(vol->sb, "Cannot truncate inode 0x%lx, attribute "
2563				"type 0x%x, because the conversion from "
2564				"resident to non-resident attribute failed "
2565				"with error code %i.", vi->i_ino,
2566				(unsigned)le32_to_cpu(ni->type), err);
2567		if (err != -ENOMEM)
2568			err = -EIO;
2569		goto conv_err_out;
2570	}
2571	/* TODO: Not implemented from here, abort. */
2572	if (err == -ENOSPC)
2573		ntfs_error(vol->sb, "Not enough space in the mft record/on "
2574				"disk for the non-resident attribute value.  "
2575				"This case is not implemented yet.");
2576	else /* if (err == -EPERM) */
2577		ntfs_error(vol->sb, "This attribute type may not be "
2578				"non-resident.  This case is not implemented "
2579				"yet.");
2580	err = -EOPNOTSUPP;
2581	goto conv_err_out;
2582#if 0
2583	// TODO: Attempt to make other attributes non-resident.
2584	if (!err)
2585		goto do_resident_extend;
2586	/*
2587	 * Both the attribute list attribute and the standard information
2588	 * attribute must remain in the base inode.  Thus, if this is one of
2589	 * these attributes, we have to try to move other attributes out into
2590	 * extent mft records instead.
2591	 */
2592	if (ni->type == AT_ATTRIBUTE_LIST ||
2593			ni->type == AT_STANDARD_INFORMATION) {
2594		// TODO: Attempt to move other attributes into extent mft
2595		// records.
2596		err = -EOPNOTSUPP;
2597		if (!err)
2598			goto do_resident_extend;
2599		goto err_out;
2600	}
2601	// TODO: Attempt to move this attribute to an extent mft record, but
2602	// only if it is not already the only attribute in an mft record in
2603	// which case there would be nothing to gain.
2604	err = -EOPNOTSUPP;
2605	if (!err)
2606		goto do_resident_extend;
2607	/* There is nothing we can do to make enough space. )-: */
2608	goto err_out;
2609#endif
2610do_non_resident_truncate:
2611	BUG_ON(!NInoNonResident(ni));
2612	if (alloc_change < 0) {
2613		highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
2614		if (highest_vcn > 0 &&
2615				old_alloc_size >> vol->cluster_size_bits >
2616				highest_vcn + 1) {
2617			/*
2618			 * This attribute has multiple extents.  Not yet
2619			 * supported.
2620			 */
2621			ntfs_error(vol->sb, "Cannot truncate inode 0x%lx, "
2622					"attribute type 0x%x, because the "
2623					"attribute is highly fragmented (it "
2624					"consists of multiple extents) and "
2625					"this case is not implemented yet.",
2626					vi->i_ino,
2627					(unsigned)le32_to_cpu(ni->type));
2628			err = -EOPNOTSUPP;
2629			goto bad_out;
2630		}
2631	}
2632	/*
2633	 * If the size is shrinking, need to reduce the initialized_size and
2634	 * the data_size before reducing the allocation.
2635	 */
2636	if (size_change < 0) {
2637		/*
2638		 * Make the valid size smaller (i_size is already up-to-date).
2639		 */
2640		write_lock_irqsave(&ni->size_lock, flags);
2641		if (new_size < ni->initialized_size) {
2642			ni->initialized_size = new_size;
2643			a->data.non_resident.initialized_size =
2644					cpu_to_sle64(new_size);
2645		}
2646		a->data.non_resident.data_size = cpu_to_sle64(new_size);
2647		write_unlock_irqrestore(&ni->size_lock, flags);
2648		flush_dcache_mft_record_page(ctx->ntfs_ino);
2649		mark_mft_record_dirty(ctx->ntfs_ino);
2650		/* If the allocated size is not changing, we are done. */
2651		if (!alloc_change)
2652			goto unm_done;
2653		/*
2654		 * If the size is shrinking it makes no sense for the
2655		 * allocation to be growing.
2656		 */
2657		BUG_ON(alloc_change > 0);
2658	} else /* if (size_change >= 0) */ {
2659		/*
2660		 * The file size is growing or staying the same but the
2661		 * allocation can be shrinking, growing or staying the same.
2662		 */
2663		if (alloc_change > 0) {
2664			/*
2665			 * We need to extend the allocation and possibly update
2666			 * the data size.  If we are updating the data size,
2667			 * since we are not touching the initialized_size we do
2668			 * not need to worry about the actual data on disk.
2669			 * And as far as the page cache is concerned, there
2670			 * will be no pages beyond the old data size and any
2671			 * partial region in the last page between the old and
2672			 * new data size (or the end of the page if the new
2673			 * data size is outside the page) does not need to be
2674			 * modified as explained above for the resident
2675			 * attribute truncate case.  To do this, we simply drop
2676			 * the locks we hold and leave all the work to our
2677			 * friendly helper ntfs_attr_extend_allocation().
2678			 */
2679			ntfs_attr_put_search_ctx(ctx);
2680			unmap_mft_record(base_ni);
2681			up_write(&ni->runlist.lock);
2682			err = ntfs_attr_extend_allocation(ni, new_size,
2683					size_change > 0 ? new_size : -1, -1);
2684			/*
2685			 * ntfs_attr_extend_allocation() will have done error
2686			 * output already.
2687			 */
2688			goto done;
2689		}
2690		if (!alloc_change)
2691			goto alloc_done;
2692	}
2693	/* alloc_change < 0 */
2694	/* Free the clusters. */
2695	nr_freed = ntfs_cluster_free(ni, new_alloc_size >>
2696			vol->cluster_size_bits, -1, ctx);
2697	m = ctx->mrec;
2698	a = ctx->attr;
2699	if (unlikely(nr_freed < 0)) {
2700		ntfs_error(vol->sb, "Failed to release cluster(s) (error code "
2701				"%lli).  Unmount and run chkdsk to recover "
2702				"the lost cluster(s).", (long long)nr_freed);
2703		NVolSetErrors(vol);
2704		nr_freed = 0;
2705	}
2706	/* Truncate the runlist. */
2707	err = ntfs_rl_truncate_nolock(vol, &ni->runlist,
2708			new_alloc_size >> vol->cluster_size_bits);
2709	/*
2710	 * If the runlist truncation failed and/or the search context is no
2711	 * longer valid, we cannot resize the attribute record or build the
2712	 * mapping pairs array thus we mark the inode bad so that no access to
2713	 * the freed clusters can happen.
2714	 */
2715	if (unlikely(err || IS_ERR(m))) {
2716		ntfs_error(vol->sb, "Failed to %s (error code %li).%s",
2717				IS_ERR(m) ?
2718				"restore attribute search context" :
2719				"truncate attribute runlist",
2720				IS_ERR(m) ? PTR_ERR(m) : err, es);
2721		err = -EIO;
2722		goto bad_out;
2723	}
2724	/* Get the size for the shrunk mapping pairs array for the runlist. */
2725	mp_size = ntfs_get_size_for_mapping_pairs(vol, ni->runlist.rl, 0, -1);
2726	if (unlikely(mp_size <= 0)) {
2727		ntfs_error(vol->sb, "Cannot shrink allocation of inode 0x%lx, "
2728				"attribute type 0x%x, because determining the "
2729				"size for the mapping pairs failed with error "
2730				"code %i.%s", vi->i_ino,
2731				(unsigned)le32_to_cpu(ni->type), mp_size, es);
2732		err = -EIO;
2733		goto bad_out;
2734	}
2735	/*
2736	 * Shrink the attribute record for the new mapping pairs array.  Note,
2737	 * this cannot fail since we are making the attribute smaller thus by
2738	 * definition there is enough space to do so.
2739	 */
2740	err = ntfs_attr_record_resize(m, a, mp_size +
2741			le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
2742	BUG_ON(err);
2743	/*
2744	 * Generate the mapping pairs array directly into the attribute record.
2745	 */
2746	err = ntfs_mapping_pairs_build(vol, (u8*)a +
2747			le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
2748			mp_size, ni->runlist.rl, 0, -1, NULL);
2749	if (unlikely(err)) {
2750		ntfs_error(vol->sb, "Cannot shrink allocation of inode 0x%lx, "
2751				"attribute type 0x%x, because building the "
2752				"mapping pairs failed with error code %i.%s",
2753				vi->i_ino, (unsigned)le32_to_cpu(ni->type),
2754				err, es);
2755		err = -EIO;
2756		goto bad_out;
2757	}
2758	/* Update the allocated/compressed size as well as the highest vcn. */
2759	a->data.non_resident.highest_vcn = cpu_to_sle64((new_alloc_size >>
2760			vol->cluster_size_bits) - 1);
2761	write_lock_irqsave(&ni->size_lock, flags);
2762	ni->allocated_size = new_alloc_size;
2763	a->data.non_resident.allocated_size = cpu_to_sle64(new_alloc_size);
2764	if (NInoSparse(ni) || NInoCompressed(ni)) {
2765		if (nr_freed) {
2766			ni->itype.compressed.size -= nr_freed <<
2767					vol->cluster_size_bits;
2768			BUG_ON(ni->itype.compressed.size < 0);
2769			a->data.non_resident.compressed_size = cpu_to_sle64(
2770					ni->itype.compressed.size);
2771			vi->i_blocks = ni->itype.compressed.size >> 9;
2772		}
2773	} else
2774		vi->i_blocks = new_alloc_size >> 9;
2775	write_unlock_irqrestore(&ni->size_lock, flags);
2776	/*
2777	 * We have shrunk the allocation.  If this is a shrinking truncate we
2778	 * have already dealt with the initialized_size and the data_size above
2779	 * and we are done.  If the truncate is only changing the allocation
2780	 * and not the data_size, we are also done.  If this is an extending
2781	 * truncate, need to extend the data_size now which is ensured by the
2782	 * fact that @size_change is positive.
2783	 */
2784alloc_done:
2785	/*
2786	 * If the size is growing, need to update it now.  If it is shrinking,
2787	 * we have already updated it above (before the allocation change).
2788	 */
2789	if (size_change > 0)
2790		a->data.non_resident.data_size = cpu_to_sle64(new_size);
2791	/* Ensure the modified mft record is written out. */
2792	flush_dcache_mft_record_page(ctx->ntfs_ino);
2793	mark_mft_record_dirty(ctx->ntfs_ino);
2794unm_done:
2795	ntfs_attr_put_search_ctx(ctx);
2796	unmap_mft_record(base_ni);
2797	up_write(&ni->runlist.lock);
2798done:
2799	/* Update the mtime and ctime on the base inode. */
2800	/* normally ->truncate shouldn't update ctime or mtime,
2801	 * but ntfs did before so it got a copy & paste version
2802	 * of file_update_time.  one day someone should fix this
2803	 * for real.
2804	 */
2805	if (!IS_NOCMTIME(VFS_I(base_ni)) && !IS_RDONLY(VFS_I(base_ni))) {
2806		struct timespec64 now = current_time(VFS_I(base_ni));
2807		int sync_it = 0;
2808
2809		if (!timespec64_equal(&VFS_I(base_ni)->i_mtime, &now) ||
2810		    !timespec64_equal(&VFS_I(base_ni)->i_ctime, &now))
2811			sync_it = 1;
2812		VFS_I(base_ni)->i_mtime = now;
2813		VFS_I(base_ni)->i_ctime = now;
2814
2815		if (sync_it)
2816			mark_inode_dirty_sync(VFS_I(base_ni));
2817	}
2818
2819	if (likely(!err)) {
2820		NInoClearTruncateFailed(ni);
2821		ntfs_debug("Done.");
2822	}
2823	return err;
2824old_bad_out:
2825	old_size = -1;
2826bad_out:
2827	if (err != -ENOMEM && err != -EOPNOTSUPP)
2828		NVolSetErrors(vol);
2829	if (err != -EOPNOTSUPP)
2830		NInoSetTruncateFailed(ni);
2831	else if (old_size >= 0)
2832		i_size_write(vi, old_size);
2833err_out:
2834	if (ctx)
2835		ntfs_attr_put_search_ctx(ctx);
2836	if (m)
2837		unmap_mft_record(base_ni);
2838	up_write(&ni->runlist.lock);
2839out:
2840	ntfs_debug("Failed.  Returning error code %i.", err);
2841	return err;
2842conv_err_out:
2843	if (err != -ENOMEM && err != -EOPNOTSUPP)
2844		NVolSetErrors(vol);
2845	if (err != -EOPNOTSUPP)
2846		NInoSetTruncateFailed(ni);
2847	else
2848		i_size_write(vi, old_size);
2849	goto out;
2850}
2851
2852/**
2853 * ntfs_truncate_vfs - wrapper for ntfs_truncate() that has no return value
2854 * @vi:		inode for which the i_size was changed
2855 *
2856 * Wrapper for ntfs_truncate() that has no return value.
2857 *
2858 * See ntfs_truncate() description above for details.
2859 */
2860#ifdef NTFS_RW
2861void ntfs_truncate_vfs(struct inode *vi) {
2862	ntfs_truncate(vi);
2863}
2864#endif
2865
2866/**
2867 * ntfs_setattr - called from notify_change() when an attribute is being changed
2868 * @mnt_userns:	user namespace of the mount the inode was found from
2869 * @dentry:	dentry whose attributes to change
2870 * @attr:	structure describing the attributes and the changes
2871 *
2872 * We have to trap VFS attempts to truncate the file described by @dentry as
2873 * soon as possible, because we do not implement changes in i_size yet.  So we
2874 * abort all i_size changes here.
2875 *
2876 * We also abort all changes of user, group, and mode as we do not implement
2877 * the NTFS ACLs yet.
2878 *
2879 * Called with ->i_mutex held.
2880 */
2881int ntfs_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
2882		 struct iattr *attr)
2883{
2884	struct inode *vi = d_inode(dentry);
2885	int err;
2886	unsigned int ia_valid = attr->ia_valid;
2887
2888	err = setattr_prepare(&init_user_ns, dentry, attr);
2889	if (err)
2890		goto out;
2891	/* We do not support NTFS ACLs yet. */
2892	if (ia_valid & (ATTR_UID | ATTR_GID | ATTR_MODE)) {
2893		ntfs_warning(vi->i_sb, "Changes in user/group/mode are not "
2894				"supported yet, ignoring.");
2895		err = -EOPNOTSUPP;
2896		goto out;
2897	}
2898	if (ia_valid & ATTR_SIZE) {
2899		if (attr->ia_size != i_size_read(vi)) {
2900			ntfs_inode *ni = NTFS_I(vi);
2901			/*
2902			 * FIXME: For now we do not support resizing of
2903			 * compressed or encrypted files yet.
2904			 */
2905			if (NInoCompressed(ni) || NInoEncrypted(ni)) {
2906				ntfs_warning(vi->i_sb, "Changes in inode size "
2907						"are not supported yet for "
2908						"%s files, ignoring.",
2909						NInoCompressed(ni) ?
2910						"compressed" : "encrypted");
2911				err = -EOPNOTSUPP;
2912			} else {
2913				truncate_setsize(vi, attr->ia_size);
2914				ntfs_truncate_vfs(vi);
2915			}
2916			if (err || ia_valid == ATTR_SIZE)
2917				goto out;
2918		} else {
2919			/*
2920			 * We skipped the truncate but must still update
2921			 * timestamps.
2922			 */
2923			ia_valid |= ATTR_MTIME | ATTR_CTIME;
2924		}
2925	}
2926	if (ia_valid & ATTR_ATIME)
2927		vi->i_atime = attr->ia_atime;
2928	if (ia_valid & ATTR_MTIME)
2929		vi->i_mtime = attr->ia_mtime;
2930	if (ia_valid & ATTR_CTIME)
2931		vi->i_ctime = attr->ia_ctime;
2932	mark_inode_dirty(vi);
2933out:
2934	return err;
2935}
2936
2937/**
2938 * ntfs_write_inode - write out a dirty inode
2939 * @vi:		inode to write out
2940 * @sync:	if true, write out synchronously
2941 *
2942 * Write out a dirty inode to disk including any extent inodes if present.
2943 *
2944 * If @sync is true, commit the inode to disk and wait for io completion.  This
2945 * is done using write_mft_record().
2946 *
2947 * If @sync is false, just schedule the write to happen but do not wait for i/o
2948 * completion.  In 2.6 kernels, scheduling usually happens just by virtue of
2949 * marking the page (and in this case mft record) dirty but we do not implement
2950 * this yet as write_mft_record() largely ignores the @sync parameter and
2951 * always performs synchronous writes.
2952 *
2953 * Return 0 on success and -errno on error.
2954 */
2955int __ntfs_write_inode(struct inode *vi, int sync)
2956{
2957	sle64 nt;
2958	ntfs_inode *ni = NTFS_I(vi);
2959	ntfs_attr_search_ctx *ctx;
2960	MFT_RECORD *m;
2961	STANDARD_INFORMATION *si;
2962	int err = 0;
2963	bool modified = false;
2964
2965	ntfs_debug("Entering for %sinode 0x%lx.", NInoAttr(ni) ? "attr " : "",
2966			vi->i_ino);
2967	/*
2968	 * Dirty attribute inodes are written via their real inodes so just
2969	 * clean them here.  Access time updates are taken care off when the
2970	 * real inode is written.
2971	 */
2972	if (NInoAttr(ni)) {
2973		NInoClearDirty(ni);
2974		ntfs_debug("Done.");
2975		return 0;
2976	}
2977	/* Map, pin, and lock the mft record belonging to the inode. */
2978	m = map_mft_record(ni);
2979	if (IS_ERR(m)) {
2980		err = PTR_ERR(m);
2981		goto err_out;
2982	}
2983	/* Update the access times in the standard information attribute. */
2984	ctx = ntfs_attr_get_search_ctx(ni, m);
2985	if (unlikely(!ctx)) {
2986		err = -ENOMEM;
2987		goto unm_err_out;
2988	}
2989	err = ntfs_attr_lookup(AT_STANDARD_INFORMATION, NULL, 0,
2990			CASE_SENSITIVE, 0, NULL, 0, ctx);
2991	if (unlikely(err)) {
2992		ntfs_attr_put_search_ctx(ctx);
2993		goto unm_err_out;
2994	}
2995	si = (STANDARD_INFORMATION*)((u8*)ctx->attr +
2996			le16_to_cpu(ctx->attr->data.resident.value_offset));
2997	/* Update the access times if they have changed. */
2998	nt = utc2ntfs(vi->i_mtime);
2999	if (si->last_data_change_time != nt) {
3000		ntfs_debug("Updating mtime for inode 0x%lx: old = 0x%llx, "
3001				"new = 0x%llx", vi->i_ino, (long long)
3002				sle64_to_cpu(si->last_data_change_time),
3003				(long long)sle64_to_cpu(nt));
3004		si->last_data_change_time = nt;
3005		modified = true;
3006	}
3007	nt = utc2ntfs(vi->i_ctime);
3008	if (si->last_mft_change_time != nt) {
3009		ntfs_debug("Updating ctime for inode 0x%lx: old = 0x%llx, "
3010				"new = 0x%llx", vi->i_ino, (long long)
3011				sle64_to_cpu(si->last_mft_change_time),
3012				(long long)sle64_to_cpu(nt));
3013		si->last_mft_change_time = nt;
3014		modified = true;
3015	}
3016	nt = utc2ntfs(vi->i_atime);
3017	if (si->last_access_time != nt) {
3018		ntfs_debug("Updating atime for inode 0x%lx: old = 0x%llx, "
3019				"new = 0x%llx", vi->i_ino,
3020				(long long)sle64_to_cpu(si->last_access_time),
3021				(long long)sle64_to_cpu(nt));
3022		si->last_access_time = nt;
3023		modified = true;
3024	}
3025	/*
3026	 * If we just modified the standard information attribute we need to
3027	 * mark the mft record it is in dirty.  We do this manually so that
3028	 * mark_inode_dirty() is not called which would redirty the inode and
3029	 * hence result in an infinite loop of trying to write the inode.
3030	 * There is no need to mark the base inode nor the base mft record
3031	 * dirty, since we are going to write this mft record below in any case
3032	 * and the base mft record may actually not have been modified so it
3033	 * might not need to be written out.
3034	 * NOTE: It is not a problem when the inode for $MFT itself is being
3035	 * written out as mark_ntfs_record_dirty() will only set I_DIRTY_PAGES
3036	 * on the $MFT inode and hence ntfs_write_inode() will not be
3037	 * re-invoked because of it which in turn is ok since the dirtied mft
3038	 * record will be cleaned and written out to disk below, i.e. before
3039	 * this function returns.
3040	 */
3041	if (modified) {
3042		flush_dcache_mft_record_page(ctx->ntfs_ino);
3043		if (!NInoTestSetDirty(ctx->ntfs_ino))
3044			mark_ntfs_record_dirty(ctx->ntfs_ino->page,
3045					ctx->ntfs_ino->page_ofs);
3046	}
3047	ntfs_attr_put_search_ctx(ctx);
3048	/* Now the access times are updated, write the base mft record. */
3049	if (NInoDirty(ni))
3050		err = write_mft_record(ni, m, sync);
3051	/* Write all attached extent mft records. */
3052	mutex_lock(&ni->extent_lock);
3053	if (ni->nr_extents > 0) {
3054		ntfs_inode **extent_nis = ni->ext.extent_ntfs_inos;
3055		int i;
3056
3057		ntfs_debug("Writing %i extent inodes.", ni->nr_extents);
3058		for (i = 0; i < ni->nr_extents; i++) {
3059			ntfs_inode *tni = extent_nis[i];
3060
3061			if (NInoDirty(tni)) {
3062				MFT_RECORD *tm = map_mft_record(tni);
3063				int ret;
3064
3065				if (IS_ERR(tm)) {
3066					if (!err || err == -ENOMEM)
3067						err = PTR_ERR(tm);
3068					continue;
3069				}
3070				ret = write_mft_record(tni, tm, sync);
3071				unmap_mft_record(tni);
3072				if (unlikely(ret)) {
3073					if (!err || err == -ENOMEM)
3074						err = ret;
3075				}
3076			}
3077		}
3078	}
3079	mutex_unlock(&ni->extent_lock);
3080	unmap_mft_record(ni);
3081	if (unlikely(err))
3082		goto err_out;
3083	ntfs_debug("Done.");
3084	return 0;
3085unm_err_out:
3086	unmap_mft_record(ni);
3087err_out:
3088	if (err == -ENOMEM) {
3089		ntfs_warning(vi->i_sb, "Not enough memory to write inode.  "
3090				"Marking the inode dirty again, so the VFS "
3091				"retries later.");
3092		mark_inode_dirty(vi);
3093	} else {
3094		ntfs_error(vi->i_sb, "Failed (error %i):  Run chkdsk.", -err);
3095		NVolSetErrors(ni->vol);
3096	}
3097	return err;
3098}
3099
3100#endif /* NTFS_RW */