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v5.9
   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 = kmem_cache_alloc(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*)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	si = (STANDARD_INFORMATION*)((u8*)a +
 633			le16_to_cpu(a->data.resident.value_offset));
 634
 635	/* Transfer information from the standard information into vi. */
 636	/*
 637	 * Note: The i_?times do not quite map perfectly onto the NTFS times,
 638	 * but they are close enough, and in the end it doesn't really matter
 639	 * that much...
 640	 */
 641	/*
 642	 * mtime is the last change of the data within the file. Not changed
 643	 * when only metadata is changed, e.g. a rename doesn't affect mtime.
 644	 */
 645	vi->i_mtime = ntfs2utc(si->last_data_change_time);
 646	/*
 647	 * ctime is the last change of the metadata of the file. This obviously
 648	 * always changes, when mtime is changed. ctime can be changed on its
 649	 * own, mtime is then not changed, e.g. when a file is renamed.
 650	 */
 651	vi->i_ctime = ntfs2utc(si->last_mft_change_time);
 652	/*
 653	 * Last access to the data within the file. Not changed during a rename
 654	 * for example but changed whenever the file is written to.
 655	 */
 656	vi->i_atime = ntfs2utc(si->last_access_time);
 657
 658	/* Find the attribute list attribute if present. */
 659	ntfs_attr_reinit_search_ctx(ctx);
 660	err = ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, 0, 0, NULL, 0, ctx);
 661	if (err) {
 662		if (unlikely(err != -ENOENT)) {
 663			ntfs_error(vi->i_sb, "Failed to lookup attribute list "
 664					"attribute.");
 665			goto unm_err_out;
 666		}
 667	} else /* if (!err) */ {
 668		if (vi->i_ino == FILE_MFT)
 669			goto skip_attr_list_load;
 670		ntfs_debug("Attribute list found in inode 0x%lx.", vi->i_ino);
 671		NInoSetAttrList(ni);
 672		a = ctx->attr;
 673		if (a->flags & ATTR_COMPRESSION_MASK) {
 674			ntfs_error(vi->i_sb, "Attribute list attribute is "
 675					"compressed.");
 676			goto unm_err_out;
 677		}
 678		if (a->flags & ATTR_IS_ENCRYPTED ||
 679				a->flags & ATTR_IS_SPARSE) {
 680			if (a->non_resident) {
 681				ntfs_error(vi->i_sb, "Non-resident attribute "
 682						"list attribute is encrypted/"
 683						"sparse.");
 684				goto unm_err_out;
 685			}
 686			ntfs_warning(vi->i_sb, "Resident attribute list "
 687					"attribute in inode 0x%lx is marked "
 688					"encrypted/sparse which is not true.  "
 689					"However, Windows allows this and "
 690					"chkdsk does not detect or correct it "
 691					"so we will just ignore the invalid "
 692					"flags and pretend they are not set.",
 693					vi->i_ino);
 694		}
 695		/* Now allocate memory for the attribute list. */
 696		ni->attr_list_size = (u32)ntfs_attr_size(a);
 697		ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
 698		if (!ni->attr_list) {
 699			ntfs_error(vi->i_sb, "Not enough memory to allocate "
 700					"buffer for attribute list.");
 701			err = -ENOMEM;
 702			goto unm_err_out;
 703		}
 704		if (a->non_resident) {
 705			NInoSetAttrListNonResident(ni);
 706			if (a->data.non_resident.lowest_vcn) {
 707				ntfs_error(vi->i_sb, "Attribute list has non "
 708						"zero lowest_vcn.");
 709				goto unm_err_out;
 710			}
 711			/*
 712			 * Setup the runlist. No need for locking as we have
 713			 * exclusive access to the inode at this time.
 714			 */
 715			ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
 716					a, NULL);
 717			if (IS_ERR(ni->attr_list_rl.rl)) {
 718				err = PTR_ERR(ni->attr_list_rl.rl);
 719				ni->attr_list_rl.rl = NULL;
 720				ntfs_error(vi->i_sb, "Mapping pairs "
 721						"decompression failed.");
 722				goto unm_err_out;
 723			}
 724			/* Now load the attribute list. */
 725			if ((err = load_attribute_list(vol, &ni->attr_list_rl,
 726					ni->attr_list, ni->attr_list_size,
 727					sle64_to_cpu(a->data.non_resident.
 728					initialized_size)))) {
 729				ntfs_error(vi->i_sb, "Failed to load "
 730						"attribute list attribute.");
 731				goto unm_err_out;
 732			}
 733		} else /* if (!a->non_resident) */ {
 734			if ((u8*)a + le16_to_cpu(a->data.resident.value_offset)
 735					+ le32_to_cpu(
 736					a->data.resident.value_length) >
 737					(u8*)ctx->mrec + vol->mft_record_size) {
 738				ntfs_error(vi->i_sb, "Corrupt attribute list "
 739						"in inode.");
 740				goto unm_err_out;
 741			}
 742			/* Now copy the attribute list. */
 743			memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
 744					a->data.resident.value_offset),
 745					le32_to_cpu(
 746					a->data.resident.value_length));
 747		}
 748	}
 749skip_attr_list_load:
 750	/*
 751	 * If an attribute list is present we now have the attribute list value
 752	 * in ntfs_ino->attr_list and it is ntfs_ino->attr_list_size bytes.
 753	 */
 754	if (S_ISDIR(vi->i_mode)) {
 755		loff_t bvi_size;
 756		ntfs_inode *bni;
 757		INDEX_ROOT *ir;
 758		u8 *ir_end, *index_end;
 759
 760		/* It is a directory, find index root attribute. */
 761		ntfs_attr_reinit_search_ctx(ctx);
 762		err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE,
 763				0, NULL, 0, ctx);
 764		if (unlikely(err)) {
 765			if (err == -ENOENT) {
 766				// FIXME: File is corrupt! Hot-fix with empty
 767				// index root attribute if recovery option is
 768				// set.
 769				ntfs_error(vi->i_sb, "$INDEX_ROOT attribute "
 770						"is missing.");
 771			}
 772			goto unm_err_out;
 773		}
 774		a = ctx->attr;
 775		/* Set up the state. */
 776		if (unlikely(a->non_resident)) {
 777			ntfs_error(vol->sb, "$INDEX_ROOT attribute is not "
 778					"resident.");
 779			goto unm_err_out;
 780		}
 781		/* Ensure the attribute name is placed before the value. */
 782		if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
 783				le16_to_cpu(a->data.resident.value_offset)))) {
 784			ntfs_error(vol->sb, "$INDEX_ROOT attribute name is "
 785					"placed after the attribute value.");
 786			goto unm_err_out;
 787		}
 788		/*
 789		 * Compressed/encrypted index root just means that the newly
 790		 * created files in that directory should be created compressed/
 791		 * encrypted. However index root cannot be both compressed and
 792		 * encrypted.
 793		 */
 794		if (a->flags & ATTR_COMPRESSION_MASK)
 795			NInoSetCompressed(ni);
 796		if (a->flags & ATTR_IS_ENCRYPTED) {
 797			if (a->flags & ATTR_COMPRESSION_MASK) {
 798				ntfs_error(vi->i_sb, "Found encrypted and "
 799						"compressed attribute.");
 800				goto unm_err_out;
 801			}
 802			NInoSetEncrypted(ni);
 803		}
 804		if (a->flags & ATTR_IS_SPARSE)
 805			NInoSetSparse(ni);
 806		ir = (INDEX_ROOT*)((u8*)a +
 807				le16_to_cpu(a->data.resident.value_offset));
 808		ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
 809		if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
 810			ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
 811					"corrupt.");
 812			goto unm_err_out;
 813		}
 814		index_end = (u8*)&ir->index +
 815				le32_to_cpu(ir->index.index_length);
 816		if (index_end > ir_end) {
 817			ntfs_error(vi->i_sb, "Directory index is corrupt.");
 818			goto unm_err_out;
 819		}
 820		if (ir->type != AT_FILE_NAME) {
 821			ntfs_error(vi->i_sb, "Indexed attribute is not "
 822					"$FILE_NAME.");
 823			goto unm_err_out;
 824		}
 825		if (ir->collation_rule != COLLATION_FILE_NAME) {
 826			ntfs_error(vi->i_sb, "Index collation rule is not "
 827					"COLLATION_FILE_NAME.");
 828			goto unm_err_out;
 829		}
 830		ni->itype.index.collation_rule = ir->collation_rule;
 831		ni->itype.index.block_size = le32_to_cpu(ir->index_block_size);
 832		if (ni->itype.index.block_size &
 833				(ni->itype.index.block_size - 1)) {
 834			ntfs_error(vi->i_sb, "Index block size (%u) is not a "
 835					"power of two.",
 836					ni->itype.index.block_size);
 837			goto unm_err_out;
 838		}
 839		if (ni->itype.index.block_size > PAGE_SIZE) {
 840			ntfs_error(vi->i_sb, "Index block size (%u) > "
 841					"PAGE_SIZE (%ld) is not "
 842					"supported.  Sorry.",
 843					ni->itype.index.block_size,
 844					PAGE_SIZE);
 845			err = -EOPNOTSUPP;
 846			goto unm_err_out;
 847		}
 848		if (ni->itype.index.block_size < NTFS_BLOCK_SIZE) {
 849			ntfs_error(vi->i_sb, "Index block size (%u) < "
 850					"NTFS_BLOCK_SIZE (%i) is not "
 851					"supported.  Sorry.",
 852					ni->itype.index.block_size,
 853					NTFS_BLOCK_SIZE);
 854			err = -EOPNOTSUPP;
 855			goto unm_err_out;
 856		}
 857		ni->itype.index.block_size_bits =
 858				ffs(ni->itype.index.block_size) - 1;
 859		/* Determine the size of a vcn in the directory index. */
 860		if (vol->cluster_size <= ni->itype.index.block_size) {
 861			ni->itype.index.vcn_size = vol->cluster_size;
 862			ni->itype.index.vcn_size_bits = vol->cluster_size_bits;
 863		} else {
 864			ni->itype.index.vcn_size = vol->sector_size;
 865			ni->itype.index.vcn_size_bits = vol->sector_size_bits;
 866		}
 867
 868		/* Setup the index allocation attribute, even if not present. */
 869		NInoSetMstProtected(ni);
 870		ni->type = AT_INDEX_ALLOCATION;
 871		ni->name = I30;
 872		ni->name_len = 4;
 873
 874		if (!(ir->index.flags & LARGE_INDEX)) {
 875			/* No index allocation. */
 876			vi->i_size = ni->initialized_size =
 877					ni->allocated_size = 0;
 878			/* We are done with the mft record, so we release it. */
 879			ntfs_attr_put_search_ctx(ctx);
 880			unmap_mft_record(ni);
 881			m = NULL;
 882			ctx = NULL;
 883			goto skip_large_dir_stuff;
 884		} /* LARGE_INDEX: Index allocation present. Setup state. */
 885		NInoSetIndexAllocPresent(ni);
 886		/* Find index allocation attribute. */
 887		ntfs_attr_reinit_search_ctx(ctx);
 888		err = ntfs_attr_lookup(AT_INDEX_ALLOCATION, I30, 4,
 889				CASE_SENSITIVE, 0, NULL, 0, ctx);
 890		if (unlikely(err)) {
 891			if (err == -ENOENT)
 892				ntfs_error(vi->i_sb, "$INDEX_ALLOCATION "
 893						"attribute is not present but "
 894						"$INDEX_ROOT indicated it is.");
 895			else
 896				ntfs_error(vi->i_sb, "Failed to lookup "
 897						"$INDEX_ALLOCATION "
 898						"attribute.");
 899			goto unm_err_out;
 900		}
 901		a = ctx->attr;
 902		if (!a->non_resident) {
 903			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 904					"is resident.");
 905			goto unm_err_out;
 906		}
 907		/*
 908		 * Ensure the attribute name is placed before the mapping pairs
 909		 * array.
 910		 */
 911		if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
 912				le16_to_cpu(
 913				a->data.non_resident.mapping_pairs_offset)))) {
 914			ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name "
 915					"is placed after the mapping pairs "
 916					"array.");
 917			goto unm_err_out;
 918		}
 919		if (a->flags & ATTR_IS_ENCRYPTED) {
 920			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 921					"is encrypted.");
 922			goto unm_err_out;
 923		}
 924		if (a->flags & ATTR_IS_SPARSE) {
 925			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 926					"is sparse.");
 927			goto unm_err_out;
 928		}
 929		if (a->flags & ATTR_COMPRESSION_MASK) {
 930			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 931					"is compressed.");
 932			goto unm_err_out;
 933		}
 934		if (a->data.non_resident.lowest_vcn) {
 935			ntfs_error(vi->i_sb, "First extent of "
 936					"$INDEX_ALLOCATION attribute has non "
 937					"zero lowest_vcn.");
 938			goto unm_err_out;
 939		}
 940		vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
 941		ni->initialized_size = sle64_to_cpu(
 942				a->data.non_resident.initialized_size);
 943		ni->allocated_size = sle64_to_cpu(
 944				a->data.non_resident.allocated_size);
 945		/*
 946		 * We are done with the mft record, so we release it. Otherwise
 947		 * we would deadlock in ntfs_attr_iget().
 948		 */
 949		ntfs_attr_put_search_ctx(ctx);
 950		unmap_mft_record(ni);
 951		m = NULL;
 952		ctx = NULL;
 953		/* Get the index bitmap attribute inode. */
 954		bvi = ntfs_attr_iget(vi, AT_BITMAP, I30, 4);
 955		if (IS_ERR(bvi)) {
 956			ntfs_error(vi->i_sb, "Failed to get bitmap attribute.");
 957			err = PTR_ERR(bvi);
 958			goto unm_err_out;
 959		}
 960		bni = NTFS_I(bvi);
 961		if (NInoCompressed(bni) || NInoEncrypted(bni) ||
 962				NInoSparse(bni)) {
 963			ntfs_error(vi->i_sb, "$BITMAP attribute is compressed "
 964					"and/or encrypted and/or sparse.");
 965			goto iput_unm_err_out;
 966		}
 967		/* Consistency check bitmap size vs. index allocation size. */
 968		bvi_size = i_size_read(bvi);
 969		if ((bvi_size << 3) < (vi->i_size >>
 970				ni->itype.index.block_size_bits)) {
 971			ntfs_error(vi->i_sb, "Index bitmap too small (0x%llx) "
 972					"for index allocation (0x%llx).",
 973					bvi_size << 3, vi->i_size);
 974			goto iput_unm_err_out;
 975		}
 976		/* No longer need the bitmap attribute inode. */
 977		iput(bvi);
 978skip_large_dir_stuff:
 979		/* Setup the operations for this inode. */
 980		vi->i_op = &ntfs_dir_inode_ops;
 981		vi->i_fop = &ntfs_dir_ops;
 982		vi->i_mapping->a_ops = &ntfs_mst_aops;
 983	} else {
 984		/* It is a file. */
 985		ntfs_attr_reinit_search_ctx(ctx);
 986
 987		/* Setup the data attribute, even if not present. */
 988		ni->type = AT_DATA;
 989		ni->name = NULL;
 990		ni->name_len = 0;
 991
 992		/* Find first extent of the unnamed data attribute. */
 993		err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, 0, NULL, 0, ctx);
 994		if (unlikely(err)) {
 995			vi->i_size = ni->initialized_size =
 996					ni->allocated_size = 0;
 997			if (err != -ENOENT) {
 998				ntfs_error(vi->i_sb, "Failed to lookup $DATA "
 999						"attribute.");
1000				goto unm_err_out;
1001			}
1002			/*
1003			 * FILE_Secure does not have an unnamed $DATA
1004			 * attribute, so we special case it here.
1005			 */
1006			if (vi->i_ino == FILE_Secure)
1007				goto no_data_attr_special_case;
1008			/*
1009			 * Most if not all the system files in the $Extend
1010			 * system directory do not have unnamed data
1011			 * attributes so we need to check if the parent
1012			 * directory of the file is FILE_Extend and if it is
1013			 * ignore this error. To do this we need to get the
1014			 * name of this inode from the mft record as the name
1015			 * contains the back reference to the parent directory.
1016			 */
1017			if (ntfs_is_extended_system_file(ctx) > 0)
1018				goto no_data_attr_special_case;
1019			// FIXME: File is corrupt! Hot-fix with empty data
1020			// attribute if recovery option is set.
1021			ntfs_error(vi->i_sb, "$DATA attribute is missing.");
1022			goto unm_err_out;
1023		}
1024		a = ctx->attr;
1025		/* Setup the state. */
1026		if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) {
1027			if (a->flags & ATTR_COMPRESSION_MASK) {
1028				NInoSetCompressed(ni);
1029				if (vol->cluster_size > 4096) {
1030					ntfs_error(vi->i_sb, "Found "
1031							"compressed data but "
1032							"compression is "
1033							"disabled due to "
1034							"cluster size (%i) > "
1035							"4kiB.",
1036							vol->cluster_size);
1037					goto unm_err_out;
1038				}
1039				if ((a->flags & ATTR_COMPRESSION_MASK)
1040						!= ATTR_IS_COMPRESSED) {
1041					ntfs_error(vi->i_sb, "Found unknown "
1042							"compression method "
1043							"or corrupt file.");
1044					goto unm_err_out;
1045				}
1046			}
1047			if (a->flags & ATTR_IS_SPARSE)
1048				NInoSetSparse(ni);
1049		}
1050		if (a->flags & ATTR_IS_ENCRYPTED) {
1051			if (NInoCompressed(ni)) {
1052				ntfs_error(vi->i_sb, "Found encrypted and "
1053						"compressed data.");
1054				goto unm_err_out;
1055			}
1056			NInoSetEncrypted(ni);
1057		}
1058		if (a->non_resident) {
1059			NInoSetNonResident(ni);
1060			if (NInoCompressed(ni) || NInoSparse(ni)) {
1061				if (NInoCompressed(ni) && a->data.non_resident.
1062						compression_unit != 4) {
1063					ntfs_error(vi->i_sb, "Found "
1064							"non-standard "
1065							"compression unit (%u "
1066							"instead of 4).  "
1067							"Cannot handle this.",
1068							a->data.non_resident.
1069							compression_unit);
1070					err = -EOPNOTSUPP;
1071					goto unm_err_out;
1072				}
1073				if (a->data.non_resident.compression_unit) {
1074					ni->itype.compressed.block_size = 1U <<
1075							(a->data.non_resident.
1076							compression_unit +
1077							vol->cluster_size_bits);
1078					ni->itype.compressed.block_size_bits =
1079							ffs(ni->itype.
1080							compressed.
1081							block_size) - 1;
1082					ni->itype.compressed.block_clusters =
1083							1U << a->data.
1084							non_resident.
1085							compression_unit;
1086				} else {
1087					ni->itype.compressed.block_size = 0;
1088					ni->itype.compressed.block_size_bits =
1089							0;
1090					ni->itype.compressed.block_clusters =
1091							0;
1092				}
1093				ni->itype.compressed.size = sle64_to_cpu(
1094						a->data.non_resident.
1095						compressed_size);
1096			}
1097			if (a->data.non_resident.lowest_vcn) {
1098				ntfs_error(vi->i_sb, "First extent of $DATA "
1099						"attribute has non zero "
1100						"lowest_vcn.");
1101				goto unm_err_out;
1102			}
1103			vi->i_size = sle64_to_cpu(
1104					a->data.non_resident.data_size);
1105			ni->initialized_size = sle64_to_cpu(
1106					a->data.non_resident.initialized_size);
1107			ni->allocated_size = sle64_to_cpu(
1108					a->data.non_resident.allocated_size);
1109		} else { /* Resident attribute. */
1110			vi->i_size = ni->initialized_size = le32_to_cpu(
1111					a->data.resident.value_length);
1112			ni->allocated_size = le32_to_cpu(a->length) -
1113					le16_to_cpu(
1114					a->data.resident.value_offset);
1115			if (vi->i_size > ni->allocated_size) {
1116				ntfs_error(vi->i_sb, "Resident data attribute "
1117						"is corrupt (size exceeds "
1118						"allocation).");
1119				goto unm_err_out;
1120			}
1121		}
1122no_data_attr_special_case:
1123		/* We are done with the mft record, so we release it. */
1124		ntfs_attr_put_search_ctx(ctx);
1125		unmap_mft_record(ni);
1126		m = NULL;
1127		ctx = NULL;
1128		/* Setup the operations for this inode. */
1129		vi->i_op = &ntfs_file_inode_ops;
1130		vi->i_fop = &ntfs_file_ops;
1131		vi->i_mapping->a_ops = &ntfs_normal_aops;
1132		if (NInoMstProtected(ni))
1133			vi->i_mapping->a_ops = &ntfs_mst_aops;
1134		else if (NInoCompressed(ni))
1135			vi->i_mapping->a_ops = &ntfs_compressed_aops;
1136	}
 
 
 
 
1137	/*
1138	 * The number of 512-byte blocks used on disk (for stat). This is in so
1139	 * far inaccurate as it doesn't account for any named streams or other
1140	 * special non-resident attributes, but that is how Windows works, too,
1141	 * so we are at least consistent with Windows, if not entirely
1142	 * consistent with the Linux Way. Doing it the Linux Way would cause a
1143	 * significant slowdown as it would involve iterating over all
1144	 * attributes in the mft record and adding the allocated/compressed
1145	 * sizes of all non-resident attributes present to give us the Linux
1146	 * correct size that should go into i_blocks (after division by 512).
1147	 */
1148	if (S_ISREG(vi->i_mode) && (NInoCompressed(ni) || NInoSparse(ni)))
1149		vi->i_blocks = ni->itype.compressed.size >> 9;
1150	else
1151		vi->i_blocks = ni->allocated_size >> 9;
1152	ntfs_debug("Done.");
1153	return 0;
1154iput_unm_err_out:
1155	iput(bvi);
1156unm_err_out:
1157	if (!err)
1158		err = -EIO;
1159	if (ctx)
1160		ntfs_attr_put_search_ctx(ctx);
1161	if (m)
1162		unmap_mft_record(ni);
1163err_out:
1164	ntfs_error(vol->sb, "Failed with error code %i.  Marking corrupt "
1165			"inode 0x%lx as bad.  Run chkdsk.", err, vi->i_ino);
1166	make_bad_inode(vi);
1167	if (err != -EOPNOTSUPP && err != -ENOMEM)
1168		NVolSetErrors(vol);
1169	return err;
1170}
1171
1172/**
1173 * ntfs_read_locked_attr_inode - read an attribute inode from its base inode
1174 * @base_vi:	base inode
1175 * @vi:		attribute inode to read
1176 *
1177 * ntfs_read_locked_attr_inode() is called from ntfs_attr_iget() to read the
1178 * attribute inode described by @vi into memory from the base mft record
1179 * described by @base_ni.
1180 *
1181 * ntfs_read_locked_attr_inode() maps, pins and locks the base inode for
1182 * reading and looks up the attribute described by @vi before setting up the
1183 * necessary fields in @vi as well as initializing the ntfs inode.
1184 *
1185 * Q: What locks are held when the function is called?
1186 * A: i_state has I_NEW set, hence the inode is locked, also
1187 *    i_count is set to 1, so it is not going to go away
1188 *
1189 * Return 0 on success and -errno on error.  In the error case, the inode will
1190 * have had make_bad_inode() executed on it.
1191 *
1192 * Note this cannot be called for AT_INDEX_ALLOCATION.
1193 */
1194static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi)
1195{
1196	ntfs_volume *vol = NTFS_SB(vi->i_sb);
1197	ntfs_inode *ni, *base_ni;
1198	MFT_RECORD *m;
1199	ATTR_RECORD *a;
1200	ntfs_attr_search_ctx *ctx;
1201	int err = 0;
1202
1203	ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
1204
1205	ntfs_init_big_inode(vi);
1206
1207	ni	= NTFS_I(vi);
1208	base_ni = NTFS_I(base_vi);
1209
1210	/* Just mirror the values from the base inode. */
 
1211	vi->i_uid	= base_vi->i_uid;
1212	vi->i_gid	= base_vi->i_gid;
1213	set_nlink(vi, base_vi->i_nlink);
1214	vi->i_mtime	= base_vi->i_mtime;
1215	vi->i_ctime	= base_vi->i_ctime;
1216	vi->i_atime	= base_vi->i_atime;
1217	vi->i_generation = ni->seq_no = base_ni->seq_no;
1218
1219	/* Set inode type to zero but preserve permissions. */
1220	vi->i_mode	= base_vi->i_mode & ~S_IFMT;
1221
1222	m = map_mft_record(base_ni);
1223	if (IS_ERR(m)) {
1224		err = PTR_ERR(m);
1225		goto err_out;
1226	}
1227	ctx = ntfs_attr_get_search_ctx(base_ni, m);
1228	if (!ctx) {
1229		err = -ENOMEM;
1230		goto unm_err_out;
1231	}
1232	/* Find the attribute. */
1233	err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
1234			CASE_SENSITIVE, 0, NULL, 0, ctx);
1235	if (unlikely(err))
1236		goto unm_err_out;
1237	a = ctx->attr;
1238	if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) {
1239		if (a->flags & ATTR_COMPRESSION_MASK) {
1240			NInoSetCompressed(ni);
1241			if ((ni->type != AT_DATA) || (ni->type == AT_DATA &&
1242					ni->name_len)) {
1243				ntfs_error(vi->i_sb, "Found compressed "
1244						"non-data or named data "
1245						"attribute.  Please report "
1246						"you saw this message to "
1247						"linux-ntfs-dev@lists."
1248						"sourceforge.net");
1249				goto unm_err_out;
1250			}
1251			if (vol->cluster_size > 4096) {
1252				ntfs_error(vi->i_sb, "Found compressed "
1253						"attribute but compression is "
1254						"disabled due to cluster size "
1255						"(%i) > 4kiB.",
1256						vol->cluster_size);
1257				goto unm_err_out;
1258			}
1259			if ((a->flags & ATTR_COMPRESSION_MASK) !=
1260					ATTR_IS_COMPRESSED) {
1261				ntfs_error(vi->i_sb, "Found unknown "
1262						"compression method.");
1263				goto unm_err_out;
1264			}
1265		}
1266		/*
1267		 * The compressed/sparse flag set in an index root just means
1268		 * to compress all files.
1269		 */
1270		if (NInoMstProtected(ni) && ni->type != AT_INDEX_ROOT) {
1271			ntfs_error(vi->i_sb, "Found mst protected attribute "
1272					"but the attribute is %s.  Please "
1273					"report you saw this message to "
1274					"linux-ntfs-dev@lists.sourceforge.net",
1275					NInoCompressed(ni) ? "compressed" :
1276					"sparse");
1277			goto unm_err_out;
1278		}
1279		if (a->flags & ATTR_IS_SPARSE)
1280			NInoSetSparse(ni);
1281	}
1282	if (a->flags & ATTR_IS_ENCRYPTED) {
1283		if (NInoCompressed(ni)) {
1284			ntfs_error(vi->i_sb, "Found encrypted and compressed "
1285					"data.");
1286			goto unm_err_out;
1287		}
1288		/*
1289		 * The encryption flag set in an index root just means to
1290		 * encrypt all files.
1291		 */
1292		if (NInoMstProtected(ni) && ni->type != AT_INDEX_ROOT) {
1293			ntfs_error(vi->i_sb, "Found mst protected attribute "
1294					"but the attribute is encrypted.  "
1295					"Please report you saw this message "
1296					"to linux-ntfs-dev@lists.sourceforge."
1297					"net");
1298			goto unm_err_out;
1299		}
1300		if (ni->type != AT_DATA) {
1301			ntfs_error(vi->i_sb, "Found encrypted non-data "
1302					"attribute.");
1303			goto unm_err_out;
1304		}
1305		NInoSetEncrypted(ni);
1306	}
1307	if (!a->non_resident) {
1308		/* Ensure the attribute name is placed before the value. */
1309		if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1310				le16_to_cpu(a->data.resident.value_offset)))) {
1311			ntfs_error(vol->sb, "Attribute name is placed after "
1312					"the attribute value.");
1313			goto unm_err_out;
1314		}
1315		if (NInoMstProtected(ni)) {
1316			ntfs_error(vi->i_sb, "Found mst protected attribute "
1317					"but the attribute is resident.  "
1318					"Please report you saw this message to "
1319					"linux-ntfs-dev@lists.sourceforge.net");
1320			goto unm_err_out;
1321		}
1322		vi->i_size = ni->initialized_size = le32_to_cpu(
1323				a->data.resident.value_length);
1324		ni->allocated_size = le32_to_cpu(a->length) -
1325				le16_to_cpu(a->data.resident.value_offset);
1326		if (vi->i_size > ni->allocated_size) {
1327			ntfs_error(vi->i_sb, "Resident attribute is corrupt "
1328					"(size exceeds allocation).");
1329			goto unm_err_out;
1330		}
1331	} else {
1332		NInoSetNonResident(ni);
1333		/*
1334		 * Ensure the attribute name is placed before the mapping pairs
1335		 * array.
1336		 */
1337		if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1338				le16_to_cpu(
1339				a->data.non_resident.mapping_pairs_offset)))) {
1340			ntfs_error(vol->sb, "Attribute name is placed after "
1341					"the mapping pairs array.");
1342			goto unm_err_out;
1343		}
1344		if (NInoCompressed(ni) || NInoSparse(ni)) {
1345			if (NInoCompressed(ni) && a->data.non_resident.
1346					compression_unit != 4) {
1347				ntfs_error(vi->i_sb, "Found non-standard "
1348						"compression unit (%u instead "
1349						"of 4).  Cannot handle this.",
1350						a->data.non_resident.
1351						compression_unit);
1352				err = -EOPNOTSUPP;
1353				goto unm_err_out;
1354			}
1355			if (a->data.non_resident.compression_unit) {
1356				ni->itype.compressed.block_size = 1U <<
1357						(a->data.non_resident.
1358						compression_unit +
1359						vol->cluster_size_bits);
1360				ni->itype.compressed.block_size_bits =
1361						ffs(ni->itype.compressed.
1362						block_size) - 1;
1363				ni->itype.compressed.block_clusters = 1U <<
1364						a->data.non_resident.
1365						compression_unit;
1366			} else {
1367				ni->itype.compressed.block_size = 0;
1368				ni->itype.compressed.block_size_bits = 0;
1369				ni->itype.compressed.block_clusters = 0;
1370			}
1371			ni->itype.compressed.size = sle64_to_cpu(
1372					a->data.non_resident.compressed_size);
1373		}
1374		if (a->data.non_resident.lowest_vcn) {
1375			ntfs_error(vi->i_sb, "First extent of attribute has "
1376					"non-zero lowest_vcn.");
1377			goto unm_err_out;
1378		}
1379		vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
1380		ni->initialized_size = sle64_to_cpu(
1381				a->data.non_resident.initialized_size);
1382		ni->allocated_size = sle64_to_cpu(
1383				a->data.non_resident.allocated_size);
1384	}
1385	vi->i_mapping->a_ops = &ntfs_normal_aops;
1386	if (NInoMstProtected(ni))
1387		vi->i_mapping->a_ops = &ntfs_mst_aops;
1388	else if (NInoCompressed(ni))
1389		vi->i_mapping->a_ops = &ntfs_compressed_aops;
1390	if ((NInoCompressed(ni) || NInoSparse(ni)) && ni->type != AT_INDEX_ROOT)
1391		vi->i_blocks = ni->itype.compressed.size >> 9;
1392	else
1393		vi->i_blocks = ni->allocated_size >> 9;
1394	/*
1395	 * Make sure the base inode does not go away and attach it to the
1396	 * attribute inode.
1397	 */
1398	igrab(base_vi);
1399	ni->ext.base_ntfs_ino = base_ni;
1400	ni->nr_extents = -1;
1401
1402	ntfs_attr_put_search_ctx(ctx);
1403	unmap_mft_record(base_ni);
1404
1405	ntfs_debug("Done.");
1406	return 0;
1407
1408unm_err_out:
1409	if (!err)
1410		err = -EIO;
1411	if (ctx)
1412		ntfs_attr_put_search_ctx(ctx);
1413	unmap_mft_record(base_ni);
1414err_out:
1415	ntfs_error(vol->sb, "Failed with error code %i while reading attribute "
1416			"inode (mft_no 0x%lx, type 0x%x, name_len %i).  "
1417			"Marking corrupt inode and base inode 0x%lx as bad.  "
1418			"Run chkdsk.", err, vi->i_ino, ni->type, ni->name_len,
1419			base_vi->i_ino);
1420	make_bad_inode(vi);
1421	if (err != -ENOMEM)
1422		NVolSetErrors(vol);
1423	return err;
1424}
1425
1426/**
1427 * ntfs_read_locked_index_inode - read an index inode from its base inode
1428 * @base_vi:	base inode
1429 * @vi:		index inode to read
1430 *
1431 * ntfs_read_locked_index_inode() is called from ntfs_index_iget() to read the
1432 * index inode described by @vi into memory from the base mft record described
1433 * by @base_ni.
1434 *
1435 * ntfs_read_locked_index_inode() maps, pins and locks the base inode for
1436 * reading and looks up the attributes relating to the index described by @vi
1437 * before setting up the necessary fields in @vi as well as initializing the
1438 * ntfs inode.
1439 *
1440 * Note, index inodes are essentially attribute inodes (NInoAttr() is true)
1441 * with the attribute type set to AT_INDEX_ALLOCATION.  Apart from that, they
1442 * are setup like directory inodes since directories are a special case of
1443 * indices ao they need to be treated in much the same way.  Most importantly,
1444 * for small indices the index allocation attribute might not actually exist.
1445 * However, the index root attribute always exists but this does not need to
1446 * have an inode associated with it and this is why we define a new inode type
1447 * index.  Also, like for directories, we need to have an attribute inode for
1448 * the bitmap attribute corresponding to the index allocation attribute and we
1449 * can store this in the appropriate field of the inode, just like we do for
1450 * normal directory inodes.
1451 *
1452 * Q: What locks are held when the function is called?
1453 * A: i_state has I_NEW set, hence the inode is locked, also
1454 *    i_count is set to 1, so it is not going to go away
1455 *
1456 * Return 0 on success and -errno on error.  In the error case, the inode will
1457 * have had make_bad_inode() executed on it.
1458 */
1459static int ntfs_read_locked_index_inode(struct inode *base_vi, struct inode *vi)
1460{
1461	loff_t bvi_size;
1462	ntfs_volume *vol = NTFS_SB(vi->i_sb);
1463	ntfs_inode *ni, *base_ni, *bni;
1464	struct inode *bvi;
1465	MFT_RECORD *m;
1466	ATTR_RECORD *a;
1467	ntfs_attr_search_ctx *ctx;
1468	INDEX_ROOT *ir;
1469	u8 *ir_end, *index_end;
1470	int err = 0;
1471
1472	ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
1473	ntfs_init_big_inode(vi);
1474	ni	= NTFS_I(vi);
1475	base_ni = NTFS_I(base_vi);
1476	/* Just mirror the values from the base inode. */
 
1477	vi->i_uid	= base_vi->i_uid;
1478	vi->i_gid	= base_vi->i_gid;
1479	set_nlink(vi, base_vi->i_nlink);
1480	vi->i_mtime	= base_vi->i_mtime;
1481	vi->i_ctime	= base_vi->i_ctime;
1482	vi->i_atime	= base_vi->i_atime;
1483	vi->i_generation = ni->seq_no = base_ni->seq_no;
1484	/* Set inode type to zero but preserve permissions. */
1485	vi->i_mode	= base_vi->i_mode & ~S_IFMT;
1486	/* Map the mft record for the base inode. */
1487	m = map_mft_record(base_ni);
1488	if (IS_ERR(m)) {
1489		err = PTR_ERR(m);
1490		goto err_out;
1491	}
1492	ctx = ntfs_attr_get_search_ctx(base_ni, m);
1493	if (!ctx) {
1494		err = -ENOMEM;
1495		goto unm_err_out;
1496	}
1497	/* Find the index root attribute. */
1498	err = ntfs_attr_lookup(AT_INDEX_ROOT, ni->name, ni->name_len,
1499			CASE_SENSITIVE, 0, NULL, 0, ctx);
1500	if (unlikely(err)) {
1501		if (err == -ENOENT)
1502			ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
1503					"missing.");
1504		goto unm_err_out;
1505	}
1506	a = ctx->attr;
1507	/* Set up the state. */
1508	if (unlikely(a->non_resident)) {
1509		ntfs_error(vol->sb, "$INDEX_ROOT attribute is not resident.");
1510		goto unm_err_out;
1511	}
1512	/* Ensure the attribute name is placed before the value. */
1513	if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1514			le16_to_cpu(a->data.resident.value_offset)))) {
1515		ntfs_error(vol->sb, "$INDEX_ROOT attribute name is placed "
1516				"after the attribute value.");
1517		goto unm_err_out;
1518	}
1519	/*
1520	 * Compressed/encrypted/sparse index root is not allowed, except for
1521	 * directories of course but those are not dealt with here.
1522	 */
1523	if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_ENCRYPTED |
1524			ATTR_IS_SPARSE)) {
1525		ntfs_error(vi->i_sb, "Found compressed/encrypted/sparse index "
1526				"root attribute.");
1527		goto unm_err_out;
1528	}
1529	ir = (INDEX_ROOT*)((u8*)a + le16_to_cpu(a->data.resident.value_offset));
1530	ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
1531	if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
1532		ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is corrupt.");
1533		goto unm_err_out;
1534	}
1535	index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length);
1536	if (index_end > ir_end) {
1537		ntfs_error(vi->i_sb, "Index is corrupt.");
1538		goto unm_err_out;
1539	}
1540	if (ir->type) {
1541		ntfs_error(vi->i_sb, "Index type is not 0 (type is 0x%x).",
1542				le32_to_cpu(ir->type));
1543		goto unm_err_out;
1544	}
1545	ni->itype.index.collation_rule = ir->collation_rule;
1546	ntfs_debug("Index collation rule is 0x%x.",
1547			le32_to_cpu(ir->collation_rule));
1548	ni->itype.index.block_size = le32_to_cpu(ir->index_block_size);
1549	if (!is_power_of_2(ni->itype.index.block_size)) {
1550		ntfs_error(vi->i_sb, "Index block size (%u) is not a power of "
1551				"two.", ni->itype.index.block_size);
1552		goto unm_err_out;
1553	}
1554	if (ni->itype.index.block_size > PAGE_SIZE) {
1555		ntfs_error(vi->i_sb, "Index block size (%u) > PAGE_SIZE "
1556				"(%ld) is not supported.  Sorry.",
1557				ni->itype.index.block_size, PAGE_SIZE);
1558		err = -EOPNOTSUPP;
1559		goto unm_err_out;
1560	}
1561	if (ni->itype.index.block_size < NTFS_BLOCK_SIZE) {
1562		ntfs_error(vi->i_sb, "Index block size (%u) < NTFS_BLOCK_SIZE "
1563				"(%i) is not supported.  Sorry.",
1564				ni->itype.index.block_size, NTFS_BLOCK_SIZE);
1565		err = -EOPNOTSUPP;
1566		goto unm_err_out;
1567	}
1568	ni->itype.index.block_size_bits = ffs(ni->itype.index.block_size) - 1;
1569	/* Determine the size of a vcn in the index. */
1570	if (vol->cluster_size <= ni->itype.index.block_size) {
1571		ni->itype.index.vcn_size = vol->cluster_size;
1572		ni->itype.index.vcn_size_bits = vol->cluster_size_bits;
1573	} else {
1574		ni->itype.index.vcn_size = vol->sector_size;
1575		ni->itype.index.vcn_size_bits = vol->sector_size_bits;
1576	}
1577	/* Check for presence of index allocation attribute. */
1578	if (!(ir->index.flags & LARGE_INDEX)) {
1579		/* No index allocation. */
1580		vi->i_size = ni->initialized_size = ni->allocated_size = 0;
1581		/* We are done with the mft record, so we release it. */
1582		ntfs_attr_put_search_ctx(ctx);
1583		unmap_mft_record(base_ni);
1584		m = NULL;
1585		ctx = NULL;
1586		goto skip_large_index_stuff;
1587	} /* LARGE_INDEX:  Index allocation present.  Setup state. */
1588	NInoSetIndexAllocPresent(ni);
1589	/* Find index allocation attribute. */
1590	ntfs_attr_reinit_search_ctx(ctx);
1591	err = ntfs_attr_lookup(AT_INDEX_ALLOCATION, ni->name, ni->name_len,
1592			CASE_SENSITIVE, 0, NULL, 0, ctx);
1593	if (unlikely(err)) {
1594		if (err == -ENOENT)
1595			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1596					"not present but $INDEX_ROOT "
1597					"indicated it is.");
1598		else
1599			ntfs_error(vi->i_sb, "Failed to lookup "
1600					"$INDEX_ALLOCATION attribute.");
1601		goto unm_err_out;
1602	}
1603	a = ctx->attr;
1604	if (!a->non_resident) {
1605		ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1606				"resident.");
1607		goto unm_err_out;
1608	}
1609	/*
1610	 * Ensure the attribute name is placed before the mapping pairs array.
1611	 */
1612	if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1613			le16_to_cpu(
1614			a->data.non_resident.mapping_pairs_offset)))) {
1615		ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name is "
1616				"placed after the mapping pairs array.");
1617		goto unm_err_out;
1618	}
1619	if (a->flags & ATTR_IS_ENCRYPTED) {
1620		ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1621				"encrypted.");
1622		goto unm_err_out;
1623	}
1624	if (a->flags & ATTR_IS_SPARSE) {
1625		ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is sparse.");
1626		goto unm_err_out;
1627	}
1628	if (a->flags & ATTR_COMPRESSION_MASK) {
1629		ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1630				"compressed.");
1631		goto unm_err_out;
1632	}
1633	if (a->data.non_resident.lowest_vcn) {
1634		ntfs_error(vi->i_sb, "First extent of $INDEX_ALLOCATION "
1635				"attribute has non zero lowest_vcn.");
1636		goto unm_err_out;
1637	}
1638	vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
1639	ni->initialized_size = sle64_to_cpu(
1640			a->data.non_resident.initialized_size);
1641	ni->allocated_size = sle64_to_cpu(a->data.non_resident.allocated_size);
1642	/*
1643	 * We are done with the mft record, so we release it.  Otherwise
1644	 * we would deadlock in ntfs_attr_iget().
1645	 */
1646	ntfs_attr_put_search_ctx(ctx);
1647	unmap_mft_record(base_ni);
1648	m = NULL;
1649	ctx = NULL;
1650	/* Get the index bitmap attribute inode. */
1651	bvi = ntfs_attr_iget(base_vi, AT_BITMAP, ni->name, ni->name_len);
1652	if (IS_ERR(bvi)) {
1653		ntfs_error(vi->i_sb, "Failed to get bitmap attribute.");
1654		err = PTR_ERR(bvi);
1655		goto unm_err_out;
1656	}
1657	bni = NTFS_I(bvi);
1658	if (NInoCompressed(bni) || NInoEncrypted(bni) ||
1659			NInoSparse(bni)) {
1660		ntfs_error(vi->i_sb, "$BITMAP attribute is compressed and/or "
1661				"encrypted and/or sparse.");
1662		goto iput_unm_err_out;
1663	}
1664	/* Consistency check bitmap size vs. index allocation size. */
1665	bvi_size = i_size_read(bvi);
1666	if ((bvi_size << 3) < (vi->i_size >> ni->itype.index.block_size_bits)) {
1667		ntfs_error(vi->i_sb, "Index bitmap too small (0x%llx) for "
1668				"index allocation (0x%llx).", bvi_size << 3,
1669				vi->i_size);
1670		goto iput_unm_err_out;
1671	}
1672	iput(bvi);
1673skip_large_index_stuff:
1674	/* Setup the operations for this index inode. */
1675	vi->i_mapping->a_ops = &ntfs_mst_aops;
1676	vi->i_blocks = ni->allocated_size >> 9;
1677	/*
1678	 * Make sure the base inode doesn't go away and attach it to the
1679	 * index inode.
1680	 */
1681	igrab(base_vi);
1682	ni->ext.base_ntfs_ino = base_ni;
1683	ni->nr_extents = -1;
1684
1685	ntfs_debug("Done.");
1686	return 0;
1687iput_unm_err_out:
1688	iput(bvi);
1689unm_err_out:
1690	if (!err)
1691		err = -EIO;
1692	if (ctx)
1693		ntfs_attr_put_search_ctx(ctx);
1694	if (m)
1695		unmap_mft_record(base_ni);
1696err_out:
1697	ntfs_error(vi->i_sb, "Failed with error code %i while reading index "
1698			"inode (mft_no 0x%lx, name_len %i.", err, vi->i_ino,
1699			ni->name_len);
1700	make_bad_inode(vi);
1701	if (err != -EOPNOTSUPP && err != -ENOMEM)
1702		NVolSetErrors(vol);
1703	return err;
1704}
1705
1706/*
1707 * The MFT inode has special locking, so teach the lock validator
1708 * about this by splitting off the locking rules of the MFT from
1709 * the locking rules of other inodes. The MFT inode can never be
1710 * accessed from the VFS side (or even internally), only by the
1711 * map_mft functions.
1712 */
1713static struct lock_class_key mft_ni_runlist_lock_key, mft_ni_mrec_lock_key;
1714
1715/**
1716 * ntfs_read_inode_mount - special read_inode for mount time use only
1717 * @vi:		inode to read
1718 *
1719 * Read inode FILE_MFT at mount time, only called with super_block lock
1720 * held from within the read_super() code path.
1721 *
1722 * This function exists because when it is called the page cache for $MFT/$DATA
1723 * is not initialized and hence we cannot get at the contents of mft records
1724 * by calling map_mft_record*().
1725 *
1726 * Further it needs to cope with the circular references problem, i.e. cannot
1727 * load any attributes other than $ATTRIBUTE_LIST until $DATA is loaded, because
1728 * we do not know where the other extent mft records are yet and again, because
1729 * we cannot call map_mft_record*() yet.  Obviously this applies only when an
1730 * attribute list is actually present in $MFT inode.
1731 *
1732 * We solve these problems by starting with the $DATA attribute before anything
1733 * else and iterating using ntfs_attr_lookup($DATA) over all extents.  As each
1734 * extent is found, we ntfs_mapping_pairs_decompress() including the implied
1735 * ntfs_runlists_merge().  Each step of the iteration necessarily provides
1736 * sufficient information for the next step to complete.
1737 *
1738 * This should work but there are two possible pit falls (see inline comments
1739 * below), but only time will tell if they are real pits or just smoke...
1740 */
1741int ntfs_read_inode_mount(struct inode *vi)
1742{
1743	VCN next_vcn, last_vcn, highest_vcn;
1744	s64 block;
1745	struct super_block *sb = vi->i_sb;
1746	ntfs_volume *vol = NTFS_SB(sb);
1747	struct buffer_head *bh;
1748	ntfs_inode *ni;
1749	MFT_RECORD *m = NULL;
1750	ATTR_RECORD *a;
1751	ntfs_attr_search_ctx *ctx;
1752	unsigned int i, nr_blocks;
1753	int err;
1754
1755	ntfs_debug("Entering.");
1756
1757	/* Initialize the ntfs specific part of @vi. */
1758	ntfs_init_big_inode(vi);
1759
1760	ni = NTFS_I(vi);
1761
1762	/* Setup the data attribute. It is special as it is mst protected. */
1763	NInoSetNonResident(ni);
1764	NInoSetMstProtected(ni);
1765	NInoSetSparseDisabled(ni);
1766	ni->type = AT_DATA;
1767	ni->name = NULL;
1768	ni->name_len = 0;
1769	/*
1770	 * This sets up our little cheat allowing us to reuse the async read io
1771	 * completion handler for directories.
1772	 */
1773	ni->itype.index.block_size = vol->mft_record_size;
1774	ni->itype.index.block_size_bits = vol->mft_record_size_bits;
1775
1776	/* Very important! Needed to be able to call map_mft_record*(). */
1777	vol->mft_ino = vi;
1778
1779	/* Allocate enough memory to read the first mft record. */
1780	if (vol->mft_record_size > 64 * 1024) {
1781		ntfs_error(sb, "Unsupported mft record size %i (max 64kiB).",
1782				vol->mft_record_size);
1783		goto err_out;
1784	}
1785	i = vol->mft_record_size;
1786	if (i < sb->s_blocksize)
1787		i = sb->s_blocksize;
1788	m = (MFT_RECORD*)ntfs_malloc_nofs(i);
1789	if (!m) {
1790		ntfs_error(sb, "Failed to allocate buffer for $MFT record 0.");
1791		goto err_out;
1792	}
1793
1794	/* Determine the first block of the $MFT/$DATA attribute. */
1795	block = vol->mft_lcn << vol->cluster_size_bits >>
1796			sb->s_blocksize_bits;
1797	nr_blocks = vol->mft_record_size >> sb->s_blocksize_bits;
1798	if (!nr_blocks)
1799		nr_blocks = 1;
1800
1801	/* Load $MFT/$DATA's first mft record. */
1802	for (i = 0; i < nr_blocks; i++) {
1803		bh = sb_bread(sb, block++);
1804		if (!bh) {
1805			ntfs_error(sb, "Device read failed.");
1806			goto err_out;
1807		}
1808		memcpy((char*)m + (i << sb->s_blocksize_bits), bh->b_data,
1809				sb->s_blocksize);
1810		brelse(bh);
1811	}
1812
1813	/* Apply the mst fixups. */
1814	if (post_read_mst_fixup((NTFS_RECORD*)m, vol->mft_record_size)) {
1815		/* FIXME: Try to use the $MFTMirr now. */
1816		ntfs_error(sb, "MST fixup failed. $MFT is corrupt.");
1817		goto err_out;
1818	}
1819
1820	/* Need this to sanity check attribute list references to $MFT. */
1821	vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);
1822
1823	/* Provides readpage() for map_mft_record(). */
1824	vi->i_mapping->a_ops = &ntfs_mst_aops;
1825
1826	ctx = ntfs_attr_get_search_ctx(ni, m);
1827	if (!ctx) {
1828		err = -ENOMEM;
1829		goto err_out;
1830	}
1831
1832	/* Find the attribute list attribute if present. */
1833	err = ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, 0, 0, NULL, 0, ctx);
1834	if (err) {
1835		if (unlikely(err != -ENOENT)) {
1836			ntfs_error(sb, "Failed to lookup attribute list "
1837					"attribute. You should run chkdsk.");
1838			goto put_err_out;
1839		}
1840	} else /* if (!err) */ {
1841		ATTR_LIST_ENTRY *al_entry, *next_al_entry;
1842		u8 *al_end;
1843		static const char *es = "  Not allowed.  $MFT is corrupt.  "
1844				"You should run chkdsk.";
1845
1846		ntfs_debug("Attribute list attribute found in $MFT.");
1847		NInoSetAttrList(ni);
1848		a = ctx->attr;
1849		if (a->flags & ATTR_COMPRESSION_MASK) {
1850			ntfs_error(sb, "Attribute list attribute is "
1851					"compressed.%s", es);
1852			goto put_err_out;
1853		}
1854		if (a->flags & ATTR_IS_ENCRYPTED ||
1855				a->flags & ATTR_IS_SPARSE) {
1856			if (a->non_resident) {
1857				ntfs_error(sb, "Non-resident attribute list "
1858						"attribute is encrypted/"
1859						"sparse.%s", es);
1860				goto put_err_out;
1861			}
1862			ntfs_warning(sb, "Resident attribute list attribute "
1863					"in $MFT system file is marked "
1864					"encrypted/sparse which is not true.  "
1865					"However, Windows allows this and "
1866					"chkdsk does not detect or correct it "
1867					"so we will just ignore the invalid "
1868					"flags and pretend they are not set.");
1869		}
1870		/* Now allocate memory for the attribute list. */
1871		ni->attr_list_size = (u32)ntfs_attr_size(a);
1872		ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
1873		if (!ni->attr_list) {
1874			ntfs_error(sb, "Not enough memory to allocate buffer "
1875					"for attribute list.");
1876			goto put_err_out;
1877		}
1878		if (a->non_resident) {
1879			NInoSetAttrListNonResident(ni);
1880			if (a->data.non_resident.lowest_vcn) {
1881				ntfs_error(sb, "Attribute list has non zero "
1882						"lowest_vcn. $MFT is corrupt. "
1883						"You should run chkdsk.");
1884				goto put_err_out;
1885			}
1886			/* Setup the runlist. */
1887			ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
1888					a, NULL);
1889			if (IS_ERR(ni->attr_list_rl.rl)) {
1890				err = PTR_ERR(ni->attr_list_rl.rl);
1891				ni->attr_list_rl.rl = NULL;
1892				ntfs_error(sb, "Mapping pairs decompression "
1893						"failed with error code %i.",
1894						-err);
1895				goto put_err_out;
1896			}
1897			/* Now load the attribute list. */
1898			if ((err = load_attribute_list(vol, &ni->attr_list_rl,
1899					ni->attr_list, ni->attr_list_size,
1900					sle64_to_cpu(a->data.
1901					non_resident.initialized_size)))) {
1902				ntfs_error(sb, "Failed to load attribute list "
1903						"attribute with error code %i.",
1904						-err);
1905				goto put_err_out;
1906			}
1907		} else /* if (!ctx.attr->non_resident) */ {
1908			if ((u8*)a + le16_to_cpu(
1909					a->data.resident.value_offset) +
1910					le32_to_cpu(
1911					a->data.resident.value_length) >
1912					(u8*)ctx->mrec + vol->mft_record_size) {
1913				ntfs_error(sb, "Corrupt attribute list "
1914						"attribute.");
1915				goto put_err_out;
1916			}
1917			/* Now copy the attribute list. */
1918			memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
1919					a->data.resident.value_offset),
1920					le32_to_cpu(
1921					a->data.resident.value_length));
1922		}
1923		/* The attribute list is now setup in memory. */
1924		/*
1925		 * FIXME: I don't know if this case is actually possible.
1926		 * According to logic it is not possible but I have seen too
1927		 * many weird things in MS software to rely on logic... Thus we
1928		 * perform a manual search and make sure the first $MFT/$DATA
1929		 * extent is in the base inode. If it is not we abort with an
1930		 * error and if we ever see a report of this error we will need
1931		 * to do some magic in order to have the necessary mft record
1932		 * loaded and in the right place in the page cache. But
1933		 * hopefully logic will prevail and this never happens...
1934		 */
1935		al_entry = (ATTR_LIST_ENTRY*)ni->attr_list;
1936		al_end = (u8*)al_entry + ni->attr_list_size;
1937		for (;; al_entry = next_al_entry) {
1938			/* Out of bounds check. */
1939			if ((u8*)al_entry < ni->attr_list ||
1940					(u8*)al_entry > al_end)
1941				goto em_put_err_out;
1942			/* Catch the end of the attribute list. */
1943			if ((u8*)al_entry == al_end)
1944				goto em_put_err_out;
1945			if (!al_entry->length)
1946				goto em_put_err_out;
1947			if ((u8*)al_entry + 6 > al_end || (u8*)al_entry +
1948					le16_to_cpu(al_entry->length) > al_end)
1949				goto em_put_err_out;
1950			next_al_entry = (ATTR_LIST_ENTRY*)((u8*)al_entry +
1951					le16_to_cpu(al_entry->length));
1952			if (le32_to_cpu(al_entry->type) > le32_to_cpu(AT_DATA))
1953				goto em_put_err_out;
1954			if (AT_DATA != al_entry->type)
1955				continue;
1956			/* We want an unnamed attribute. */
1957			if (al_entry->name_length)
1958				goto em_put_err_out;
1959			/* Want the first entry, i.e. lowest_vcn == 0. */
1960			if (al_entry->lowest_vcn)
1961				goto em_put_err_out;
1962			/* First entry has to be in the base mft record. */
1963			if (MREF_LE(al_entry->mft_reference) != vi->i_ino) {
1964				/* MFT references do not match, logic fails. */
1965				ntfs_error(sb, "BUG: The first $DATA extent "
1966						"of $MFT is not in the base "
1967						"mft record. Please report "
1968						"you saw this message to "
1969						"linux-ntfs-dev@lists."
1970						"sourceforge.net");
1971				goto put_err_out;
1972			} else {
1973				/* Sequence numbers must match. */
1974				if (MSEQNO_LE(al_entry->mft_reference) !=
1975						ni->seq_no)
1976					goto em_put_err_out;
1977				/* Got it. All is ok. We can stop now. */
1978				break;
1979			}
1980		}
1981	}
1982
1983	ntfs_attr_reinit_search_ctx(ctx);
1984
1985	/* Now load all attribute extents. */
1986	a = NULL;
1987	next_vcn = last_vcn = highest_vcn = 0;
1988	while (!(err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, next_vcn, NULL, 0,
1989			ctx))) {
1990		runlist_element *nrl;
1991
1992		/* Cache the current attribute. */
1993		a = ctx->attr;
1994		/* $MFT must be non-resident. */
1995		if (!a->non_resident) {
1996			ntfs_error(sb, "$MFT must be non-resident but a "
1997					"resident extent was found. $MFT is "
1998					"corrupt. Run chkdsk.");
1999			goto put_err_out;
2000		}
2001		/* $MFT must be uncompressed and unencrypted. */
2002		if (a->flags & ATTR_COMPRESSION_MASK ||
2003				a->flags & ATTR_IS_ENCRYPTED ||
2004				a->flags & ATTR_IS_SPARSE) {
2005			ntfs_error(sb, "$MFT must be uncompressed, "
2006					"non-sparse, and unencrypted but a "
2007					"compressed/sparse/encrypted extent "
2008					"was found. $MFT is corrupt. Run "
2009					"chkdsk.");
2010			goto put_err_out;
2011		}
2012		/*
2013		 * Decompress the mapping pairs array of this extent and merge
2014		 * the result into the existing runlist. No need for locking
2015		 * as we have exclusive access to the inode at this time and we
2016		 * are a mount in progress task, too.
2017		 */
2018		nrl = ntfs_mapping_pairs_decompress(vol, a, ni->runlist.rl);
2019		if (IS_ERR(nrl)) {
2020			ntfs_error(sb, "ntfs_mapping_pairs_decompress() "
2021					"failed with error code %ld.  $MFT is "
2022					"corrupt.", PTR_ERR(nrl));
2023			goto put_err_out;
2024		}
2025		ni->runlist.rl = nrl;
2026
2027		/* Are we in the first extent? */
2028		if (!next_vcn) {
2029			if (a->data.non_resident.lowest_vcn) {
2030				ntfs_error(sb, "First extent of $DATA "
2031						"attribute has non zero "
2032						"lowest_vcn. $MFT is corrupt. "
2033						"You should run chkdsk.");
2034				goto put_err_out;
2035			}
2036			/* Get the last vcn in the $DATA attribute. */
2037			last_vcn = sle64_to_cpu(
2038					a->data.non_resident.allocated_size)
2039					>> vol->cluster_size_bits;
2040			/* Fill in the inode size. */
2041			vi->i_size = sle64_to_cpu(
2042					a->data.non_resident.data_size);
2043			ni->initialized_size = sle64_to_cpu(
2044					a->data.non_resident.initialized_size);
2045			ni->allocated_size = sle64_to_cpu(
2046					a->data.non_resident.allocated_size);
2047			/*
2048			 * Verify the number of mft records does not exceed
2049			 * 2^32 - 1.
2050			 */
2051			if ((vi->i_size >> vol->mft_record_size_bits) >=
2052					(1ULL << 32)) {
2053				ntfs_error(sb, "$MFT is too big! Aborting.");
2054				goto put_err_out;
2055			}
2056			/*
2057			 * We have got the first extent of the runlist for
2058			 * $MFT which means it is now relatively safe to call
2059			 * the normal ntfs_read_inode() function.
2060			 * Complete reading the inode, this will actually
2061			 * re-read the mft record for $MFT, this time entering
2062			 * it into the page cache with which we complete the
2063			 * kick start of the volume. It should be safe to do
2064			 * this now as the first extent of $MFT/$DATA is
2065			 * already known and we would hope that we don't need
2066			 * further extents in order to find the other
2067			 * attributes belonging to $MFT. Only time will tell if
2068			 * this is really the case. If not we will have to play
2069			 * magic at this point, possibly duplicating a lot of
2070			 * ntfs_read_inode() at this point. We will need to
2071			 * ensure we do enough of its work to be able to call
2072			 * ntfs_read_inode() on extents of $MFT/$DATA. But lets
2073			 * hope this never happens...
2074			 */
2075			ntfs_read_locked_inode(vi);
2076			if (is_bad_inode(vi)) {
2077				ntfs_error(sb, "ntfs_read_inode() of $MFT "
2078						"failed. BUG or corrupt $MFT. "
2079						"Run chkdsk and if no errors "
2080						"are found, please report you "
2081						"saw this message to "
2082						"linux-ntfs-dev@lists."
2083						"sourceforge.net");
2084				ntfs_attr_put_search_ctx(ctx);
2085				/* Revert to the safe super operations. */
2086				ntfs_free(m);
2087				return -1;
2088			}
2089			/*
2090			 * Re-initialize some specifics about $MFT's inode as
2091			 * ntfs_read_inode() will have set up the default ones.
2092			 */
2093			/* Set uid and gid to root. */
2094			vi->i_uid = GLOBAL_ROOT_UID;
2095			vi->i_gid = GLOBAL_ROOT_GID;
2096			/* Regular file. No access for anyone. */
2097			vi->i_mode = S_IFREG;
2098			/* No VFS initiated operations allowed for $MFT. */
2099			vi->i_op = &ntfs_empty_inode_ops;
2100			vi->i_fop = &ntfs_empty_file_ops;
2101		}
2102
2103		/* Get the lowest vcn for the next extent. */
2104		highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
2105		next_vcn = highest_vcn + 1;
2106
2107		/* Only one extent or error, which we catch below. */
2108		if (next_vcn <= 0)
2109			break;
2110
2111		/* Avoid endless loops due to corruption. */
2112		if (next_vcn < sle64_to_cpu(
2113				a->data.non_resident.lowest_vcn)) {
2114			ntfs_error(sb, "$MFT has corrupt attribute list "
2115					"attribute. Run chkdsk.");
2116			goto put_err_out;
2117		}
2118	}
2119	if (err != -ENOENT) {
2120		ntfs_error(sb, "Failed to lookup $MFT/$DATA attribute extent. "
2121				"$MFT is corrupt. Run chkdsk.");
2122		goto put_err_out;
2123	}
2124	if (!a) {
2125		ntfs_error(sb, "$MFT/$DATA attribute not found. $MFT is "
2126				"corrupt. Run chkdsk.");
2127		goto put_err_out;
2128	}
2129	if (highest_vcn && highest_vcn != last_vcn - 1) {
2130		ntfs_error(sb, "Failed to load the complete runlist for "
2131				"$MFT/$DATA. Driver bug or corrupt $MFT. "
2132				"Run chkdsk.");
2133		ntfs_debug("highest_vcn = 0x%llx, last_vcn - 1 = 0x%llx",
2134				(unsigned long long)highest_vcn,
2135				(unsigned long long)last_vcn - 1);
2136		goto put_err_out;
2137	}
2138	ntfs_attr_put_search_ctx(ctx);
2139	ntfs_debug("Done.");
2140	ntfs_free(m);
2141
2142	/*
2143	 * Split the locking rules of the MFT inode from the
2144	 * locking rules of other inodes:
2145	 */
2146	lockdep_set_class(&ni->runlist.lock, &mft_ni_runlist_lock_key);
2147	lockdep_set_class(&ni->mrec_lock, &mft_ni_mrec_lock_key);
2148
2149	return 0;
2150
2151em_put_err_out:
2152	ntfs_error(sb, "Couldn't find first extent of $DATA attribute in "
2153			"attribute list. $MFT is corrupt. Run chkdsk.");
2154put_err_out:
2155	ntfs_attr_put_search_ctx(ctx);
2156err_out:
2157	ntfs_error(sb, "Failed. Marking inode as bad.");
2158	make_bad_inode(vi);
2159	ntfs_free(m);
2160	return -1;
2161}
2162
2163static void __ntfs_clear_inode(ntfs_inode *ni)
2164{
2165	/* Free all alocated memory. */
2166	down_write(&ni->runlist.lock);
2167	if (ni->runlist.rl) {
2168		ntfs_free(ni->runlist.rl);
2169		ni->runlist.rl = NULL;
2170	}
2171	up_write(&ni->runlist.lock);
2172
2173	if (ni->attr_list) {
2174		ntfs_free(ni->attr_list);
2175		ni->attr_list = NULL;
2176	}
2177
2178	down_write(&ni->attr_list_rl.lock);
2179	if (ni->attr_list_rl.rl) {
2180		ntfs_free(ni->attr_list_rl.rl);
2181		ni->attr_list_rl.rl = NULL;
2182	}
2183	up_write(&ni->attr_list_rl.lock);
2184
2185	if (ni->name_len && ni->name != I30) {
2186		/* Catch bugs... */
2187		BUG_ON(!ni->name);
2188		kfree(ni->name);
2189	}
2190}
2191
2192void ntfs_clear_extent_inode(ntfs_inode *ni)
2193{
2194	ntfs_debug("Entering for inode 0x%lx.", ni->mft_no);
2195
2196	BUG_ON(NInoAttr(ni));
2197	BUG_ON(ni->nr_extents != -1);
2198
2199#ifdef NTFS_RW
2200	if (NInoDirty(ni)) {
2201		if (!is_bad_inode(VFS_I(ni->ext.base_ntfs_ino)))
2202			ntfs_error(ni->vol->sb, "Clearing dirty extent inode!  "
2203					"Losing data!  This is a BUG!!!");
2204		// FIXME:  Do something!!!
2205	}
2206#endif /* NTFS_RW */
2207
2208	__ntfs_clear_inode(ni);
2209
2210	/* Bye, bye... */
2211	ntfs_destroy_extent_inode(ni);
2212}
2213
2214/**
2215 * ntfs_evict_big_inode - clean up the ntfs specific part of an inode
2216 * @vi:		vfs inode pending annihilation
2217 *
2218 * When the VFS is going to remove an inode from memory, ntfs_clear_big_inode()
2219 * is called, which deallocates all memory belonging to the NTFS specific part
2220 * of the inode and returns.
2221 *
2222 * If the MFT record is dirty, we commit it before doing anything else.
2223 */
2224void ntfs_evict_big_inode(struct inode *vi)
2225{
2226	ntfs_inode *ni = NTFS_I(vi);
2227
2228	truncate_inode_pages_final(&vi->i_data);
2229	clear_inode(vi);
2230
2231#ifdef NTFS_RW
2232	if (NInoDirty(ni)) {
2233		bool was_bad = (is_bad_inode(vi));
2234
2235		/* Committing the inode also commits all extent inodes. */
2236		ntfs_commit_inode(vi);
2237
2238		if (!was_bad && (is_bad_inode(vi) || NInoDirty(ni))) {
2239			ntfs_error(vi->i_sb, "Failed to commit dirty inode "
2240					"0x%lx.  Losing data!", vi->i_ino);
2241			// FIXME:  Do something!!!
2242		}
2243	}
2244#endif /* NTFS_RW */
2245
2246	/* No need to lock at this stage as no one else has a reference. */
2247	if (ni->nr_extents > 0) {
2248		int i;
2249
2250		for (i = 0; i < ni->nr_extents; i++)
2251			ntfs_clear_extent_inode(ni->ext.extent_ntfs_inos[i]);
2252		kfree(ni->ext.extent_ntfs_inos);
2253	}
2254
2255	__ntfs_clear_inode(ni);
2256
2257	if (NInoAttr(ni)) {
2258		/* Release the base inode if we are holding it. */
2259		if (ni->nr_extents == -1) {
2260			iput(VFS_I(ni->ext.base_ntfs_ino));
2261			ni->nr_extents = 0;
2262			ni->ext.base_ntfs_ino = NULL;
2263		}
2264	}
2265	BUG_ON(ni->page);
2266	if (!atomic_dec_and_test(&ni->count))
2267		BUG();
2268	return;
2269}
2270
2271/**
2272 * ntfs_show_options - show mount options in /proc/mounts
2273 * @sf:		seq_file in which to write our mount options
2274 * @root:	root of the mounted tree whose mount options to display
2275 *
2276 * Called by the VFS once for each mounted ntfs volume when someone reads
2277 * /proc/mounts in order to display the NTFS specific mount options of each
2278 * mount. The mount options of fs specified by @root are written to the seq file
2279 * @sf and success is returned.
2280 */
2281int ntfs_show_options(struct seq_file *sf, struct dentry *root)
2282{
2283	ntfs_volume *vol = NTFS_SB(root->d_sb);
2284	int i;
2285
2286	seq_printf(sf, ",uid=%i", from_kuid_munged(&init_user_ns, vol->uid));
2287	seq_printf(sf, ",gid=%i", from_kgid_munged(&init_user_ns, vol->gid));
2288	if (vol->fmask == vol->dmask)
2289		seq_printf(sf, ",umask=0%o", vol->fmask);
2290	else {
2291		seq_printf(sf, ",fmask=0%o", vol->fmask);
2292		seq_printf(sf, ",dmask=0%o", vol->dmask);
2293	}
2294	seq_printf(sf, ",nls=%s", vol->nls_map->charset);
2295	if (NVolCaseSensitive(vol))
2296		seq_printf(sf, ",case_sensitive");
2297	if (NVolShowSystemFiles(vol))
2298		seq_printf(sf, ",show_sys_files");
2299	if (!NVolSparseEnabled(vol))
2300		seq_printf(sf, ",disable_sparse");
2301	for (i = 0; on_errors_arr[i].val; i++) {
2302		if (on_errors_arr[i].val & vol->on_errors)
2303			seq_printf(sf, ",errors=%s", on_errors_arr[i].str);
2304	}
2305	seq_printf(sf, ",mft_zone_multiplier=%i", vol->mft_zone_multiplier);
2306	return 0;
2307}
2308
2309#ifdef NTFS_RW
2310
2311static const char *es = "  Leaving inconsistent metadata.  Unmount and run "
2312		"chkdsk.";
2313
2314/**
2315 * ntfs_truncate - called when the i_size of an ntfs inode is changed
2316 * @vi:		inode for which the i_size was changed
2317 *
2318 * We only support i_size changes for normal files at present, i.e. not
2319 * compressed and not encrypted.  This is enforced in ntfs_setattr(), see
2320 * below.
2321 *
2322 * The kernel guarantees that @vi is a regular file (S_ISREG() is true) and
2323 * that the change is allowed.
2324 *
2325 * This implies for us that @vi is a file inode rather than a directory, index,
2326 * or attribute inode as well as that @vi is a base inode.
2327 *
2328 * Returns 0 on success or -errno on error.
2329 *
2330 * Called with ->i_mutex held.
2331 */
2332int ntfs_truncate(struct inode *vi)
2333{
2334	s64 new_size, old_size, nr_freed, new_alloc_size, old_alloc_size;
2335	VCN highest_vcn;
2336	unsigned long flags;
2337	ntfs_inode *base_ni, *ni = NTFS_I(vi);
2338	ntfs_volume *vol = ni->vol;
2339	ntfs_attr_search_ctx *ctx;
2340	MFT_RECORD *m;
2341	ATTR_RECORD *a;
2342	const char *te = "  Leaving file length out of sync with i_size.";
2343	int err, mp_size, size_change, alloc_change;
2344	u32 attr_len;
2345
2346	ntfs_debug("Entering for inode 0x%lx.", vi->i_ino);
2347	BUG_ON(NInoAttr(ni));
2348	BUG_ON(S_ISDIR(vi->i_mode));
2349	BUG_ON(NInoMstProtected(ni));
2350	BUG_ON(ni->nr_extents < 0);
2351retry_truncate:
2352	/*
2353	 * Lock the runlist for writing and map the mft record to ensure it is
2354	 * safe to mess with the attribute runlist and sizes.
2355	 */
2356	down_write(&ni->runlist.lock);
2357	if (!NInoAttr(ni))
2358		base_ni = ni;
2359	else
2360		base_ni = ni->ext.base_ntfs_ino;
2361	m = map_mft_record(base_ni);
2362	if (IS_ERR(m)) {
2363		err = PTR_ERR(m);
2364		ntfs_error(vi->i_sb, "Failed to map mft record for inode 0x%lx "
2365				"(error code %d).%s", vi->i_ino, err, te);
2366		ctx = NULL;
2367		m = NULL;
2368		goto old_bad_out;
2369	}
2370	ctx = ntfs_attr_get_search_ctx(base_ni, m);
2371	if (unlikely(!ctx)) {
2372		ntfs_error(vi->i_sb, "Failed to allocate a search context for "
2373				"inode 0x%lx (not enough memory).%s",
2374				vi->i_ino, te);
2375		err = -ENOMEM;
2376		goto old_bad_out;
2377	}
2378	err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
2379			CASE_SENSITIVE, 0, NULL, 0, ctx);
2380	if (unlikely(err)) {
2381		if (err == -ENOENT) {
2382			ntfs_error(vi->i_sb, "Open attribute is missing from "
2383					"mft record.  Inode 0x%lx is corrupt.  "
2384					"Run chkdsk.%s", vi->i_ino, te);
2385			err = -EIO;
2386		} else
2387			ntfs_error(vi->i_sb, "Failed to lookup attribute in "
2388					"inode 0x%lx (error code %d).%s",
2389					vi->i_ino, err, te);
2390		goto old_bad_out;
2391	}
2392	m = ctx->mrec;
2393	a = ctx->attr;
2394	/*
2395	 * The i_size of the vfs inode is the new size for the attribute value.
2396	 */
2397	new_size = i_size_read(vi);
2398	/* The current size of the attribute value is the old size. */
2399	old_size = ntfs_attr_size(a);
2400	/* Calculate the new allocated size. */
2401	if (NInoNonResident(ni))
2402		new_alloc_size = (new_size + vol->cluster_size - 1) &
2403				~(s64)vol->cluster_size_mask;
2404	else
2405		new_alloc_size = (new_size + 7) & ~7;
2406	/* The current allocated size is the old allocated size. */
2407	read_lock_irqsave(&ni->size_lock, flags);
2408	old_alloc_size = ni->allocated_size;
2409	read_unlock_irqrestore(&ni->size_lock, flags);
2410	/*
2411	 * The change in the file size.  This will be 0 if no change, >0 if the
2412	 * size is growing, and <0 if the size is shrinking.
2413	 */
2414	size_change = -1;
2415	if (new_size - old_size >= 0) {
2416		size_change = 1;
2417		if (new_size == old_size)
2418			size_change = 0;
2419	}
2420	/* As above for the allocated size. */
2421	alloc_change = -1;
2422	if (new_alloc_size - old_alloc_size >= 0) {
2423		alloc_change = 1;
2424		if (new_alloc_size == old_alloc_size)
2425			alloc_change = 0;
2426	}
2427	/*
2428	 * If neither the size nor the allocation are being changed there is
2429	 * nothing to do.
2430	 */
2431	if (!size_change && !alloc_change)
2432		goto unm_done;
2433	/* If the size is changing, check if new size is allowed in $AttrDef. */
2434	if (size_change) {
2435		err = ntfs_attr_size_bounds_check(vol, ni->type, new_size);
2436		if (unlikely(err)) {
2437			if (err == -ERANGE) {
2438				ntfs_error(vol->sb, "Truncate would cause the "
2439						"inode 0x%lx to %simum size "
2440						"for its attribute type "
2441						"(0x%x).  Aborting truncate.",
2442						vi->i_ino,
2443						new_size > old_size ? "exceed "
2444						"the max" : "go under the min",
2445						le32_to_cpu(ni->type));
2446				err = -EFBIG;
2447			} else {
2448				ntfs_error(vol->sb, "Inode 0x%lx has unknown "
2449						"attribute type 0x%x.  "
2450						"Aborting truncate.",
2451						vi->i_ino,
2452						le32_to_cpu(ni->type));
2453				err = -EIO;
2454			}
2455			/* Reset the vfs inode size to the old size. */
2456			i_size_write(vi, old_size);
2457			goto err_out;
2458		}
2459	}
2460	if (NInoCompressed(ni) || NInoEncrypted(ni)) {
2461		ntfs_warning(vi->i_sb, "Changes in inode size are not "
2462				"supported yet for %s files, ignoring.",
2463				NInoCompressed(ni) ? "compressed" :
2464				"encrypted");
2465		err = -EOPNOTSUPP;
2466		goto bad_out;
2467	}
2468	if (a->non_resident)
2469		goto do_non_resident_truncate;
2470	BUG_ON(NInoNonResident(ni));
2471	/* Resize the attribute record to best fit the new attribute size. */
2472	if (new_size < vol->mft_record_size &&
2473			!ntfs_resident_attr_value_resize(m, a, new_size)) {
2474		/* The resize succeeded! */
2475		flush_dcache_mft_record_page(ctx->ntfs_ino);
2476		mark_mft_record_dirty(ctx->ntfs_ino);
2477		write_lock_irqsave(&ni->size_lock, flags);
2478		/* Update the sizes in the ntfs inode and all is done. */
2479		ni->allocated_size = le32_to_cpu(a->length) -
2480				le16_to_cpu(a->data.resident.value_offset);
2481		/*
2482		 * Note ntfs_resident_attr_value_resize() has already done any
2483		 * necessary data clearing in the attribute record.  When the
2484		 * file is being shrunk vmtruncate() will already have cleared
2485		 * the top part of the last partial page, i.e. since this is
2486		 * the resident case this is the page with index 0.  However,
2487		 * when the file is being expanded, the page cache page data
2488		 * between the old data_size, i.e. old_size, and the new_size
2489		 * has not been zeroed.  Fortunately, we do not need to zero it
2490		 * either since on one hand it will either already be zero due
2491		 * to both readpage and writepage clearing partial page data
2492		 * beyond i_size in which case there is nothing to do or in the
2493		 * case of the file being mmap()ped at the same time, POSIX
2494		 * specifies that the behaviour is unspecified thus we do not
2495		 * have to do anything.  This means that in our implementation
2496		 * in the rare case that the file is mmap()ped and a write
2497		 * occurred into the mmap()ped region just beyond the file size
2498		 * and writepage has not yet been called to write out the page
2499		 * (which would clear the area beyond the file size) and we now
2500		 * extend the file size to incorporate this dirty region
2501		 * outside the file size, a write of the page would result in
2502		 * this data being written to disk instead of being cleared.
2503		 * Given both POSIX and the Linux mmap(2) man page specify that
2504		 * this corner case is undefined, we choose to leave it like
2505		 * that as this is much simpler for us as we cannot lock the
2506		 * relevant page now since we are holding too many ntfs locks
2507		 * which would result in a lock reversal deadlock.
2508		 */
2509		ni->initialized_size = new_size;
2510		write_unlock_irqrestore(&ni->size_lock, flags);
2511		goto unm_done;
2512	}
2513	/* If the above resize failed, this must be an attribute extension. */
2514	BUG_ON(size_change < 0);
2515	/*
2516	 * We have to drop all the locks so we can call
2517	 * ntfs_attr_make_non_resident().  This could be optimised by try-
2518	 * locking the first page cache page and only if that fails dropping
2519	 * the locks, locking the page, and redoing all the locking and
2520	 * lookups.  While this would be a huge optimisation, it is not worth
2521	 * it as this is definitely a slow code path as it only ever can happen
2522	 * once for any given file.
2523	 */
2524	ntfs_attr_put_search_ctx(ctx);
2525	unmap_mft_record(base_ni);
2526	up_write(&ni->runlist.lock);
2527	/*
2528	 * Not enough space in the mft record, try to make the attribute
2529	 * non-resident and if successful restart the truncation process.
2530	 */
2531	err = ntfs_attr_make_non_resident(ni, old_size);
2532	if (likely(!err))
2533		goto retry_truncate;
2534	/*
2535	 * Could not make non-resident.  If this is due to this not being
2536	 * permitted for this attribute type or there not being enough space,
2537	 * try to make other attributes non-resident.  Otherwise fail.
2538	 */
2539	if (unlikely(err != -EPERM && err != -ENOSPC)) {
2540		ntfs_error(vol->sb, "Cannot truncate inode 0x%lx, attribute "
2541				"type 0x%x, because the conversion from "
2542				"resident to non-resident attribute failed "
2543				"with error code %i.", vi->i_ino,
2544				(unsigned)le32_to_cpu(ni->type), err);
2545		if (err != -ENOMEM)
2546			err = -EIO;
2547		goto conv_err_out;
2548	}
2549	/* TODO: Not implemented from here, abort. */
2550	if (err == -ENOSPC)
2551		ntfs_error(vol->sb, "Not enough space in the mft record/on "
2552				"disk for the non-resident attribute value.  "
2553				"This case is not implemented yet.");
2554	else /* if (err == -EPERM) */
2555		ntfs_error(vol->sb, "This attribute type may not be "
2556				"non-resident.  This case is not implemented "
2557				"yet.");
2558	err = -EOPNOTSUPP;
2559	goto conv_err_out;
2560#if 0
2561	// TODO: Attempt to make other attributes non-resident.
2562	if (!err)
2563		goto do_resident_extend;
2564	/*
2565	 * Both the attribute list attribute and the standard information
2566	 * attribute must remain in the base inode.  Thus, if this is one of
2567	 * these attributes, we have to try to move other attributes out into
2568	 * extent mft records instead.
2569	 */
2570	if (ni->type == AT_ATTRIBUTE_LIST ||
2571			ni->type == AT_STANDARD_INFORMATION) {
2572		// TODO: Attempt to move other attributes into extent mft
2573		// records.
2574		err = -EOPNOTSUPP;
2575		if (!err)
2576			goto do_resident_extend;
2577		goto err_out;
2578	}
2579	// TODO: Attempt to move this attribute to an extent mft record, but
2580	// only if it is not already the only attribute in an mft record in
2581	// which case there would be nothing to gain.
2582	err = -EOPNOTSUPP;
2583	if (!err)
2584		goto do_resident_extend;
2585	/* There is nothing we can do to make enough space. )-: */
2586	goto err_out;
2587#endif
2588do_non_resident_truncate:
2589	BUG_ON(!NInoNonResident(ni));
2590	if (alloc_change < 0) {
2591		highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
2592		if (highest_vcn > 0 &&
2593				old_alloc_size >> vol->cluster_size_bits >
2594				highest_vcn + 1) {
2595			/*
2596			 * This attribute has multiple extents.  Not yet
2597			 * supported.
2598			 */
2599			ntfs_error(vol->sb, "Cannot truncate inode 0x%lx, "
2600					"attribute type 0x%x, because the "
2601					"attribute is highly fragmented (it "
2602					"consists of multiple extents) and "
2603					"this case is not implemented yet.",
2604					vi->i_ino,
2605					(unsigned)le32_to_cpu(ni->type));
2606			err = -EOPNOTSUPP;
2607			goto bad_out;
2608		}
2609	}
2610	/*
2611	 * If the size is shrinking, need to reduce the initialized_size and
2612	 * the data_size before reducing the allocation.
2613	 */
2614	if (size_change < 0) {
2615		/*
2616		 * Make the valid size smaller (i_size is already up-to-date).
2617		 */
2618		write_lock_irqsave(&ni->size_lock, flags);
2619		if (new_size < ni->initialized_size) {
2620			ni->initialized_size = new_size;
2621			a->data.non_resident.initialized_size =
2622					cpu_to_sle64(new_size);
2623		}
2624		a->data.non_resident.data_size = cpu_to_sle64(new_size);
2625		write_unlock_irqrestore(&ni->size_lock, flags);
2626		flush_dcache_mft_record_page(ctx->ntfs_ino);
2627		mark_mft_record_dirty(ctx->ntfs_ino);
2628		/* If the allocated size is not changing, we are done. */
2629		if (!alloc_change)
2630			goto unm_done;
2631		/*
2632		 * If the size is shrinking it makes no sense for the
2633		 * allocation to be growing.
2634		 */
2635		BUG_ON(alloc_change > 0);
2636	} else /* if (size_change >= 0) */ {
2637		/*
2638		 * The file size is growing or staying the same but the
2639		 * allocation can be shrinking, growing or staying the same.
2640		 */
2641		if (alloc_change > 0) {
2642			/*
2643			 * We need to extend the allocation and possibly update
2644			 * the data size.  If we are updating the data size,
2645			 * since we are not touching the initialized_size we do
2646			 * not need to worry about the actual data on disk.
2647			 * And as far as the page cache is concerned, there
2648			 * will be no pages beyond the old data size and any
2649			 * partial region in the last page between the old and
2650			 * new data size (or the end of the page if the new
2651			 * data size is outside the page) does not need to be
2652			 * modified as explained above for the resident
2653			 * attribute truncate case.  To do this, we simply drop
2654			 * the locks we hold and leave all the work to our
2655			 * friendly helper ntfs_attr_extend_allocation().
2656			 */
2657			ntfs_attr_put_search_ctx(ctx);
2658			unmap_mft_record(base_ni);
2659			up_write(&ni->runlist.lock);
2660			err = ntfs_attr_extend_allocation(ni, new_size,
2661					size_change > 0 ? new_size : -1, -1);
2662			/*
2663			 * ntfs_attr_extend_allocation() will have done error
2664			 * output already.
2665			 */
2666			goto done;
2667		}
2668		if (!alloc_change)
2669			goto alloc_done;
2670	}
2671	/* alloc_change < 0 */
2672	/* Free the clusters. */
2673	nr_freed = ntfs_cluster_free(ni, new_alloc_size >>
2674			vol->cluster_size_bits, -1, ctx);
2675	m = ctx->mrec;
2676	a = ctx->attr;
2677	if (unlikely(nr_freed < 0)) {
2678		ntfs_error(vol->sb, "Failed to release cluster(s) (error code "
2679				"%lli).  Unmount and run chkdsk to recover "
2680				"the lost cluster(s).", (long long)nr_freed);
2681		NVolSetErrors(vol);
2682		nr_freed = 0;
2683	}
2684	/* Truncate the runlist. */
2685	err = ntfs_rl_truncate_nolock(vol, &ni->runlist,
2686			new_alloc_size >> vol->cluster_size_bits);
2687	/*
2688	 * If the runlist truncation failed and/or the search context is no
2689	 * longer valid, we cannot resize the attribute record or build the
2690	 * mapping pairs array thus we mark the inode bad so that no access to
2691	 * the freed clusters can happen.
2692	 */
2693	if (unlikely(err || IS_ERR(m))) {
2694		ntfs_error(vol->sb, "Failed to %s (error code %li).%s",
2695				IS_ERR(m) ?
2696				"restore attribute search context" :
2697				"truncate attribute runlist",
2698				IS_ERR(m) ? PTR_ERR(m) : err, es);
2699		err = -EIO;
2700		goto bad_out;
2701	}
2702	/* Get the size for the shrunk mapping pairs array for the runlist. */
2703	mp_size = ntfs_get_size_for_mapping_pairs(vol, ni->runlist.rl, 0, -1);
2704	if (unlikely(mp_size <= 0)) {
2705		ntfs_error(vol->sb, "Cannot shrink allocation of inode 0x%lx, "
2706				"attribute type 0x%x, because determining the "
2707				"size for the mapping pairs failed with error "
2708				"code %i.%s", vi->i_ino,
2709				(unsigned)le32_to_cpu(ni->type), mp_size, es);
2710		err = -EIO;
2711		goto bad_out;
2712	}
2713	/*
2714	 * Shrink the attribute record for the new mapping pairs array.  Note,
2715	 * this cannot fail since we are making the attribute smaller thus by
2716	 * definition there is enough space to do so.
2717	 */
2718	attr_len = le32_to_cpu(a->length);
2719	err = ntfs_attr_record_resize(m, a, mp_size +
2720			le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
2721	BUG_ON(err);
2722	/*
2723	 * Generate the mapping pairs array directly into the attribute record.
2724	 */
2725	err = ntfs_mapping_pairs_build(vol, (u8*)a +
2726			le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
2727			mp_size, ni->runlist.rl, 0, -1, NULL);
2728	if (unlikely(err)) {
2729		ntfs_error(vol->sb, "Cannot shrink allocation of inode 0x%lx, "
2730				"attribute type 0x%x, because building the "
2731				"mapping pairs failed with error code %i.%s",
2732				vi->i_ino, (unsigned)le32_to_cpu(ni->type),
2733				err, es);
2734		err = -EIO;
2735		goto bad_out;
2736	}
2737	/* Update the allocated/compressed size as well as the highest vcn. */
2738	a->data.non_resident.highest_vcn = cpu_to_sle64((new_alloc_size >>
2739			vol->cluster_size_bits) - 1);
2740	write_lock_irqsave(&ni->size_lock, flags);
2741	ni->allocated_size = new_alloc_size;
2742	a->data.non_resident.allocated_size = cpu_to_sle64(new_alloc_size);
2743	if (NInoSparse(ni) || NInoCompressed(ni)) {
2744		if (nr_freed) {
2745			ni->itype.compressed.size -= nr_freed <<
2746					vol->cluster_size_bits;
2747			BUG_ON(ni->itype.compressed.size < 0);
2748			a->data.non_resident.compressed_size = cpu_to_sle64(
2749					ni->itype.compressed.size);
2750			vi->i_blocks = ni->itype.compressed.size >> 9;
2751		}
2752	} else
2753		vi->i_blocks = new_alloc_size >> 9;
2754	write_unlock_irqrestore(&ni->size_lock, flags);
2755	/*
2756	 * We have shrunk the allocation.  If this is a shrinking truncate we
2757	 * have already dealt with the initialized_size and the data_size above
2758	 * and we are done.  If the truncate is only changing the allocation
2759	 * and not the data_size, we are also done.  If this is an extending
2760	 * truncate, need to extend the data_size now which is ensured by the
2761	 * fact that @size_change is positive.
2762	 */
2763alloc_done:
2764	/*
2765	 * If the size is growing, need to update it now.  If it is shrinking,
2766	 * we have already updated it above (before the allocation change).
2767	 */
2768	if (size_change > 0)
2769		a->data.non_resident.data_size = cpu_to_sle64(new_size);
2770	/* Ensure the modified mft record is written out. */
2771	flush_dcache_mft_record_page(ctx->ntfs_ino);
2772	mark_mft_record_dirty(ctx->ntfs_ino);
2773unm_done:
2774	ntfs_attr_put_search_ctx(ctx);
2775	unmap_mft_record(base_ni);
2776	up_write(&ni->runlist.lock);
2777done:
2778	/* Update the mtime and ctime on the base inode. */
2779	/* normally ->truncate shouldn't update ctime or mtime,
2780	 * but ntfs did before so it got a copy & paste version
2781	 * of file_update_time.  one day someone should fix this
2782	 * for real.
2783	 */
2784	if (!IS_NOCMTIME(VFS_I(base_ni)) && !IS_RDONLY(VFS_I(base_ni))) {
2785		struct timespec64 now = current_time(VFS_I(base_ni));
2786		int sync_it = 0;
2787
2788		if (!timespec64_equal(&VFS_I(base_ni)->i_mtime, &now) ||
2789		    !timespec64_equal(&VFS_I(base_ni)->i_ctime, &now))
2790			sync_it = 1;
2791		VFS_I(base_ni)->i_mtime = now;
2792		VFS_I(base_ni)->i_ctime = now;
2793
2794		if (sync_it)
2795			mark_inode_dirty_sync(VFS_I(base_ni));
2796	}
2797
2798	if (likely(!err)) {
2799		NInoClearTruncateFailed(ni);
2800		ntfs_debug("Done.");
2801	}
2802	return err;
2803old_bad_out:
2804	old_size = -1;
2805bad_out:
2806	if (err != -ENOMEM && err != -EOPNOTSUPP)
2807		NVolSetErrors(vol);
2808	if (err != -EOPNOTSUPP)
2809		NInoSetTruncateFailed(ni);
2810	else if (old_size >= 0)
2811		i_size_write(vi, old_size);
2812err_out:
2813	if (ctx)
2814		ntfs_attr_put_search_ctx(ctx);
2815	if (m)
2816		unmap_mft_record(base_ni);
2817	up_write(&ni->runlist.lock);
2818out:
2819	ntfs_debug("Failed.  Returning error code %i.", err);
2820	return err;
2821conv_err_out:
2822	if (err != -ENOMEM && err != -EOPNOTSUPP)
2823		NVolSetErrors(vol);
2824	if (err != -EOPNOTSUPP)
2825		NInoSetTruncateFailed(ni);
2826	else
2827		i_size_write(vi, old_size);
2828	goto out;
2829}
2830
2831/**
2832 * ntfs_truncate_vfs - wrapper for ntfs_truncate() that has no return value
2833 * @vi:		inode for which the i_size was changed
2834 *
2835 * Wrapper for ntfs_truncate() that has no return value.
2836 *
2837 * See ntfs_truncate() description above for details.
2838 */
2839#ifdef NTFS_RW
2840void ntfs_truncate_vfs(struct inode *vi) {
2841	ntfs_truncate(vi);
2842}
2843#endif
2844
2845/**
2846 * ntfs_setattr - called from notify_change() when an attribute is being changed
2847 * @dentry:	dentry whose attributes to change
2848 * @attr:	structure describing the attributes and the changes
2849 *
2850 * We have to trap VFS attempts to truncate the file described by @dentry as
2851 * soon as possible, because we do not implement changes in i_size yet.  So we
2852 * abort all i_size changes here.
2853 *
2854 * We also abort all changes of user, group, and mode as we do not implement
2855 * the NTFS ACLs yet.
2856 *
2857 * Called with ->i_mutex held.
2858 */
2859int ntfs_setattr(struct dentry *dentry, struct iattr *attr)
2860{
2861	struct inode *vi = d_inode(dentry);
2862	int err;
2863	unsigned int ia_valid = attr->ia_valid;
2864
2865	err = setattr_prepare(dentry, attr);
2866	if (err)
2867		goto out;
2868	/* We do not support NTFS ACLs yet. */
2869	if (ia_valid & (ATTR_UID | ATTR_GID | ATTR_MODE)) {
2870		ntfs_warning(vi->i_sb, "Changes in user/group/mode are not "
2871				"supported yet, ignoring.");
2872		err = -EOPNOTSUPP;
2873		goto out;
2874	}
2875	if (ia_valid & ATTR_SIZE) {
2876		if (attr->ia_size != i_size_read(vi)) {
2877			ntfs_inode *ni = NTFS_I(vi);
2878			/*
2879			 * FIXME: For now we do not support resizing of
2880			 * compressed or encrypted files yet.
2881			 */
2882			if (NInoCompressed(ni) || NInoEncrypted(ni)) {
2883				ntfs_warning(vi->i_sb, "Changes in inode size "
2884						"are not supported yet for "
2885						"%s files, ignoring.",
2886						NInoCompressed(ni) ?
2887						"compressed" : "encrypted");
2888				err = -EOPNOTSUPP;
2889			} else {
2890				truncate_setsize(vi, attr->ia_size);
2891				ntfs_truncate_vfs(vi);
2892			}
2893			if (err || ia_valid == ATTR_SIZE)
2894				goto out;
2895		} else {
2896			/*
2897			 * We skipped the truncate but must still update
2898			 * timestamps.
2899			 */
2900			ia_valid |= ATTR_MTIME | ATTR_CTIME;
2901		}
2902	}
2903	if (ia_valid & ATTR_ATIME)
2904		vi->i_atime = attr->ia_atime;
 
2905	if (ia_valid & ATTR_MTIME)
2906		vi->i_mtime = attr->ia_mtime;
 
2907	if (ia_valid & ATTR_CTIME)
2908		vi->i_ctime = attr->ia_ctime;
 
2909	mark_inode_dirty(vi);
2910out:
2911	return err;
2912}
2913
2914/**
2915 * ntfs_write_inode - write out a dirty inode
2916 * @vi:		inode to write out
2917 * @sync:	if true, write out synchronously
2918 *
2919 * Write out a dirty inode to disk including any extent inodes if present.
2920 *
2921 * If @sync is true, commit the inode to disk and wait for io completion.  This
2922 * is done using write_mft_record().
2923 *
2924 * If @sync is false, just schedule the write to happen but do not wait for i/o
2925 * completion.  In 2.6 kernels, scheduling usually happens just by virtue of
2926 * marking the page (and in this case mft record) dirty but we do not implement
2927 * this yet as write_mft_record() largely ignores the @sync parameter and
2928 * always performs synchronous writes.
2929 *
2930 * Return 0 on success and -errno on error.
2931 */
2932int __ntfs_write_inode(struct inode *vi, int sync)
2933{
2934	sle64 nt;
2935	ntfs_inode *ni = NTFS_I(vi);
2936	ntfs_attr_search_ctx *ctx;
2937	MFT_RECORD *m;
2938	STANDARD_INFORMATION *si;
2939	int err = 0;
2940	bool modified = false;
2941
2942	ntfs_debug("Entering for %sinode 0x%lx.", NInoAttr(ni) ? "attr " : "",
2943			vi->i_ino);
2944	/*
2945	 * Dirty attribute inodes are written via their real inodes so just
2946	 * clean them here.  Access time updates are taken care off when the
2947	 * real inode is written.
2948	 */
2949	if (NInoAttr(ni)) {
2950		NInoClearDirty(ni);
2951		ntfs_debug("Done.");
2952		return 0;
2953	}
2954	/* Map, pin, and lock the mft record belonging to the inode. */
2955	m = map_mft_record(ni);
2956	if (IS_ERR(m)) {
2957		err = PTR_ERR(m);
2958		goto err_out;
2959	}
2960	/* Update the access times in the standard information attribute. */
2961	ctx = ntfs_attr_get_search_ctx(ni, m);
2962	if (unlikely(!ctx)) {
2963		err = -ENOMEM;
2964		goto unm_err_out;
2965	}
2966	err = ntfs_attr_lookup(AT_STANDARD_INFORMATION, NULL, 0,
2967			CASE_SENSITIVE, 0, NULL, 0, ctx);
2968	if (unlikely(err)) {
2969		ntfs_attr_put_search_ctx(ctx);
2970		goto unm_err_out;
2971	}
2972	si = (STANDARD_INFORMATION*)((u8*)ctx->attr +
2973			le16_to_cpu(ctx->attr->data.resident.value_offset));
2974	/* Update the access times if they have changed. */
2975	nt = utc2ntfs(vi->i_mtime);
2976	if (si->last_data_change_time != nt) {
2977		ntfs_debug("Updating mtime for inode 0x%lx: old = 0x%llx, "
2978				"new = 0x%llx", vi->i_ino, (long long)
2979				sle64_to_cpu(si->last_data_change_time),
2980				(long long)sle64_to_cpu(nt));
2981		si->last_data_change_time = nt;
2982		modified = true;
2983	}
2984	nt = utc2ntfs(vi->i_ctime);
2985	if (si->last_mft_change_time != nt) {
2986		ntfs_debug("Updating ctime for inode 0x%lx: old = 0x%llx, "
2987				"new = 0x%llx", vi->i_ino, (long long)
2988				sle64_to_cpu(si->last_mft_change_time),
2989				(long long)sle64_to_cpu(nt));
2990		si->last_mft_change_time = nt;
2991		modified = true;
2992	}
2993	nt = utc2ntfs(vi->i_atime);
2994	if (si->last_access_time != nt) {
2995		ntfs_debug("Updating atime for inode 0x%lx: old = 0x%llx, "
2996				"new = 0x%llx", vi->i_ino,
2997				(long long)sle64_to_cpu(si->last_access_time),
2998				(long long)sle64_to_cpu(nt));
2999		si->last_access_time = nt;
3000		modified = true;
3001	}
3002	/*
3003	 * If we just modified the standard information attribute we need to
3004	 * mark the mft record it is in dirty.  We do this manually so that
3005	 * mark_inode_dirty() is not called which would redirty the inode and
3006	 * hence result in an infinite loop of trying to write the inode.
3007	 * There is no need to mark the base inode nor the base mft record
3008	 * dirty, since we are going to write this mft record below in any case
3009	 * and the base mft record may actually not have been modified so it
3010	 * might not need to be written out.
3011	 * NOTE: It is not a problem when the inode for $MFT itself is being
3012	 * written out as mark_ntfs_record_dirty() will only set I_DIRTY_PAGES
3013	 * on the $MFT inode and hence ntfs_write_inode() will not be
3014	 * re-invoked because of it which in turn is ok since the dirtied mft
3015	 * record will be cleaned and written out to disk below, i.e. before
3016	 * this function returns.
3017	 */
3018	if (modified) {
3019		flush_dcache_mft_record_page(ctx->ntfs_ino);
3020		if (!NInoTestSetDirty(ctx->ntfs_ino))
3021			mark_ntfs_record_dirty(ctx->ntfs_ino->page,
3022					ctx->ntfs_ino->page_ofs);
3023	}
3024	ntfs_attr_put_search_ctx(ctx);
3025	/* Now the access times are updated, write the base mft record. */
3026	if (NInoDirty(ni))
3027		err = write_mft_record(ni, m, sync);
3028	/* Write all attached extent mft records. */
3029	mutex_lock(&ni->extent_lock);
3030	if (ni->nr_extents > 0) {
3031		ntfs_inode **extent_nis = ni->ext.extent_ntfs_inos;
3032		int i;
3033
3034		ntfs_debug("Writing %i extent inodes.", ni->nr_extents);
3035		for (i = 0; i < ni->nr_extents; i++) {
3036			ntfs_inode *tni = extent_nis[i];
3037
3038			if (NInoDirty(tni)) {
3039				MFT_RECORD *tm = map_mft_record(tni);
3040				int ret;
3041
3042				if (IS_ERR(tm)) {
3043					if (!err || err == -ENOMEM)
3044						err = PTR_ERR(tm);
3045					continue;
3046				}
3047				ret = write_mft_record(tni, tm, sync);
3048				unmap_mft_record(tni);
3049				if (unlikely(ret)) {
3050					if (!err || err == -ENOMEM)
3051						err = ret;
3052				}
3053			}
3054		}
3055	}
3056	mutex_unlock(&ni->extent_lock);
3057	unmap_mft_record(ni);
3058	if (unlikely(err))
3059		goto err_out;
3060	ntfs_debug("Done.");
3061	return 0;
3062unm_err_out:
3063	unmap_mft_record(ni);
3064err_out:
3065	if (err == -ENOMEM) {
3066		ntfs_warning(vi->i_sb, "Not enough memory to write inode.  "
3067				"Marking the inode dirty again, so the VFS "
3068				"retries later.");
3069		mark_inode_dirty(vi);
3070	} else {
3071		ntfs_error(vi->i_sb, "Failed (error %i):  Run chkdsk.", -err);
3072		NVolSetErrors(ni->vol);
3073	}
3074	return err;
3075}
3076
3077#endif /* NTFS_RW */
v3.15
 
   1/**
   2 * inode.c - NTFS kernel inode handling. Part of the Linux-NTFS project.
   3 *
   4 * Copyright (c) 2001-2007 Anton Altaparmakov
   5 *
   6 * This program/include file is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public License as published
   8 * by the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program/include file is distributed in the hope that it will be
  12 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  13 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program (in the main directory of the Linux-NTFS
  18 * distribution in the file COPYING); if not, write to the Free Software
  19 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20 */
  21
  22#include <linux/buffer_head.h>
  23#include <linux/fs.h>
  24#include <linux/mm.h>
  25#include <linux/mount.h>
  26#include <linux/mutex.h>
  27#include <linux/pagemap.h>
  28#include <linux/quotaops.h>
  29#include <linux/slab.h>
  30#include <linux/log2.h>
  31#include <linux/aio.h>
  32
  33#include "aops.h"
  34#include "attrib.h"
  35#include "bitmap.h"
  36#include "dir.h"
  37#include "debug.h"
  38#include "inode.h"
  39#include "lcnalloc.h"
  40#include "malloc.h"
  41#include "mft.h"
  42#include "time.h"
  43#include "ntfs.h"
  44
  45/**
  46 * ntfs_test_inode - compare two (possibly fake) inodes for equality
  47 * @vi:		vfs inode which to test
  48 * @na:		ntfs attribute which is being tested with
  49 *
  50 * Compare the ntfs attribute embedded in the ntfs specific part of the vfs
  51 * inode @vi for equality with the ntfs attribute @na.
  52 *
  53 * If searching for the normal file/directory inode, set @na->type to AT_UNUSED.
  54 * @na->name and @na->name_len are then ignored.
  55 *
  56 * Return 1 if the attributes match and 0 if not.
  57 *
  58 * NOTE: This function runs with the inode_hash_lock spin lock held so it is not
  59 * allowed to sleep.
  60 */
  61int ntfs_test_inode(struct inode *vi, ntfs_attr *na)
  62{
 
  63	ntfs_inode *ni;
  64
  65	if (vi->i_ino != na->mft_no)
  66		return 0;
  67	ni = NTFS_I(vi);
  68	/* If !NInoAttr(ni), @vi is a normal file or directory inode. */
  69	if (likely(!NInoAttr(ni))) {
  70		/* If not looking for a normal inode this is a mismatch. */
  71		if (unlikely(na->type != AT_UNUSED))
  72			return 0;
  73	} else {
  74		/* A fake inode describing an attribute. */
  75		if (ni->type != na->type)
  76			return 0;
  77		if (ni->name_len != na->name_len)
  78			return 0;
  79		if (na->name_len && memcmp(ni->name, na->name,
  80				na->name_len * sizeof(ntfschar)))
  81			return 0;
  82	}
  83	/* Match! */
  84	return 1;
  85}
  86
  87/**
  88 * ntfs_init_locked_inode - initialize an inode
  89 * @vi:		vfs inode to initialize
  90 * @na:		ntfs attribute which to initialize @vi to
  91 *
  92 * Initialize the vfs inode @vi with the values from the ntfs attribute @na in
  93 * order to enable ntfs_test_inode() to do its work.
  94 *
  95 * If initializing the normal file/directory inode, set @na->type to AT_UNUSED.
  96 * In that case, @na->name and @na->name_len should be set to NULL and 0,
  97 * respectively. Although that is not strictly necessary as
  98 * ntfs_read_locked_inode() will fill them in later.
  99 *
 100 * Return 0 on success and -errno on error.
 101 *
 102 * NOTE: This function runs with the inode->i_lock spin lock held so it is not
 103 * allowed to sleep. (Hence the GFP_ATOMIC allocation.)
 104 */
 105static int ntfs_init_locked_inode(struct inode *vi, ntfs_attr *na)
 106{
 
 107	ntfs_inode *ni = NTFS_I(vi);
 108
 109	vi->i_ino = na->mft_no;
 110
 111	ni->type = na->type;
 112	if (na->type == AT_INDEX_ALLOCATION)
 113		NInoSetMstProtected(ni);
 114
 115	ni->name = na->name;
 116	ni->name_len = na->name_len;
 117
 118	/* If initializing a normal inode, we are done. */
 119	if (likely(na->type == AT_UNUSED)) {
 120		BUG_ON(na->name);
 121		BUG_ON(na->name_len);
 122		return 0;
 123	}
 124
 125	/* It is a fake inode. */
 126	NInoSetAttr(ni);
 127
 128	/*
 129	 * We have I30 global constant as an optimization as it is the name
 130	 * in >99.9% of named attributes! The other <0.1% incur a GFP_ATOMIC
 131	 * allocation but that is ok. And most attributes are unnamed anyway,
 132	 * thus the fraction of named attributes with name != I30 is actually
 133	 * absolutely tiny.
 134	 */
 135	if (na->name_len && na->name != I30) {
 136		unsigned int i;
 137
 138		BUG_ON(!na->name);
 139		i = na->name_len * sizeof(ntfschar);
 140		ni->name = kmalloc(i + sizeof(ntfschar), GFP_ATOMIC);
 141		if (!ni->name)
 142			return -ENOMEM;
 143		memcpy(ni->name, na->name, i);
 144		ni->name[na->name_len] = 0;
 145	}
 146	return 0;
 147}
 148
 149typedef int (*set_t)(struct inode *, void *);
 150static int ntfs_read_locked_inode(struct inode *vi);
 151static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi);
 152static int ntfs_read_locked_index_inode(struct inode *base_vi,
 153		struct inode *vi);
 154
 155/**
 156 * ntfs_iget - obtain a struct inode corresponding to a specific normal inode
 157 * @sb:		super block of mounted volume
 158 * @mft_no:	mft record number / inode number to obtain
 159 *
 160 * Obtain the struct inode corresponding to a specific normal inode (i.e. a
 161 * file or directory).
 162 *
 163 * If the inode is in the cache, it is just returned with an increased
 164 * reference count. Otherwise, a new struct inode is allocated and initialized,
 165 * and finally ntfs_read_locked_inode() is called to read in the inode and
 166 * fill in the remainder of the inode structure.
 167 *
 168 * Return the struct inode on success. Check the return value with IS_ERR() and
 169 * if true, the function failed and the error code is obtained from PTR_ERR().
 170 */
 171struct inode *ntfs_iget(struct super_block *sb, unsigned long mft_no)
 172{
 173	struct inode *vi;
 174	int err;
 175	ntfs_attr na;
 176
 177	na.mft_no = mft_no;
 178	na.type = AT_UNUSED;
 179	na.name = NULL;
 180	na.name_len = 0;
 181
 182	vi = iget5_locked(sb, mft_no, (test_t)ntfs_test_inode,
 183			(set_t)ntfs_init_locked_inode, &na);
 184	if (unlikely(!vi))
 185		return ERR_PTR(-ENOMEM);
 186
 187	err = 0;
 188
 189	/* If this is a freshly allocated inode, need to read it now. */
 190	if (vi->i_state & I_NEW) {
 191		err = ntfs_read_locked_inode(vi);
 192		unlock_new_inode(vi);
 193	}
 194	/*
 195	 * There is no point in keeping bad inodes around if the failure was
 196	 * due to ENOMEM. We want to be able to retry again later.
 197	 */
 198	if (unlikely(err == -ENOMEM)) {
 199		iput(vi);
 200		vi = ERR_PTR(err);
 201	}
 202	return vi;
 203}
 204
 205/**
 206 * ntfs_attr_iget - obtain a struct inode corresponding to an attribute
 207 * @base_vi:	vfs base inode containing the attribute
 208 * @type:	attribute type
 209 * @name:	Unicode name of the attribute (NULL if unnamed)
 210 * @name_len:	length of @name in Unicode characters (0 if unnamed)
 211 *
 212 * Obtain the (fake) struct inode corresponding to the attribute specified by
 213 * @type, @name, and @name_len, which is present in the base mft record
 214 * specified by the vfs inode @base_vi.
 215 *
 216 * If the attribute inode is in the cache, it is just returned with an
 217 * increased reference count. Otherwise, a new struct inode is allocated and
 218 * initialized, and finally ntfs_read_locked_attr_inode() is called to read the
 219 * attribute and fill in the inode structure.
 220 *
 221 * Note, for index allocation attributes, you need to use ntfs_index_iget()
 222 * instead of ntfs_attr_iget() as working with indices is a lot more complex.
 223 *
 224 * Return the struct inode of the attribute inode on success. Check the return
 225 * value with IS_ERR() and if true, the function failed and the error code is
 226 * obtained from PTR_ERR().
 227 */
 228struct inode *ntfs_attr_iget(struct inode *base_vi, ATTR_TYPE type,
 229		ntfschar *name, u32 name_len)
 230{
 231	struct inode *vi;
 232	int err;
 233	ntfs_attr na;
 234
 235	/* Make sure no one calls ntfs_attr_iget() for indices. */
 236	BUG_ON(type == AT_INDEX_ALLOCATION);
 237
 238	na.mft_no = base_vi->i_ino;
 239	na.type = type;
 240	na.name = name;
 241	na.name_len = name_len;
 242
 243	vi = iget5_locked(base_vi->i_sb, na.mft_no, (test_t)ntfs_test_inode,
 244			(set_t)ntfs_init_locked_inode, &na);
 245	if (unlikely(!vi))
 246		return ERR_PTR(-ENOMEM);
 247
 248	err = 0;
 249
 250	/* If this is a freshly allocated inode, need to read it now. */
 251	if (vi->i_state & I_NEW) {
 252		err = ntfs_read_locked_attr_inode(base_vi, vi);
 253		unlock_new_inode(vi);
 254	}
 255	/*
 256	 * There is no point in keeping bad attribute inodes around. This also
 257	 * simplifies things in that we never need to check for bad attribute
 258	 * inodes elsewhere.
 259	 */
 260	if (unlikely(err)) {
 261		iput(vi);
 262		vi = ERR_PTR(err);
 263	}
 264	return vi;
 265}
 266
 267/**
 268 * ntfs_index_iget - obtain a struct inode corresponding to an index
 269 * @base_vi:	vfs base inode containing the index related attributes
 270 * @name:	Unicode name of the index
 271 * @name_len:	length of @name in Unicode characters
 272 *
 273 * Obtain the (fake) struct inode corresponding to the index specified by @name
 274 * and @name_len, which is present in the base mft record specified by the vfs
 275 * inode @base_vi.
 276 *
 277 * If the index inode is in the cache, it is just returned with an increased
 278 * reference count.  Otherwise, a new struct inode is allocated and
 279 * initialized, and finally ntfs_read_locked_index_inode() is called to read
 280 * the index related attributes and fill in the inode structure.
 281 *
 282 * Return the struct inode of the index inode on success. Check the return
 283 * value with IS_ERR() and if true, the function failed and the error code is
 284 * obtained from PTR_ERR().
 285 */
 286struct inode *ntfs_index_iget(struct inode *base_vi, ntfschar *name,
 287		u32 name_len)
 288{
 289	struct inode *vi;
 290	int err;
 291	ntfs_attr na;
 292
 293	na.mft_no = base_vi->i_ino;
 294	na.type = AT_INDEX_ALLOCATION;
 295	na.name = name;
 296	na.name_len = name_len;
 297
 298	vi = iget5_locked(base_vi->i_sb, na.mft_no, (test_t)ntfs_test_inode,
 299			(set_t)ntfs_init_locked_inode, &na);
 300	if (unlikely(!vi))
 301		return ERR_PTR(-ENOMEM);
 302
 303	err = 0;
 304
 305	/* If this is a freshly allocated inode, need to read it now. */
 306	if (vi->i_state & I_NEW) {
 307		err = ntfs_read_locked_index_inode(base_vi, vi);
 308		unlock_new_inode(vi);
 309	}
 310	/*
 311	 * There is no point in keeping bad index inodes around.  This also
 312	 * simplifies things in that we never need to check for bad index
 313	 * inodes elsewhere.
 314	 */
 315	if (unlikely(err)) {
 316		iput(vi);
 317		vi = ERR_PTR(err);
 318	}
 319	return vi;
 320}
 321
 322struct inode *ntfs_alloc_big_inode(struct super_block *sb)
 323{
 324	ntfs_inode *ni;
 325
 326	ntfs_debug("Entering.");
 327	ni = kmem_cache_alloc(ntfs_big_inode_cache, GFP_NOFS);
 328	if (likely(ni != NULL)) {
 329		ni->state = 0;
 330		return VFS_I(ni);
 331	}
 332	ntfs_error(sb, "Allocation of NTFS big inode structure failed.");
 333	return NULL;
 334}
 335
 336static void ntfs_i_callback(struct rcu_head *head)
 337{
 338	struct inode *inode = container_of(head, struct inode, i_rcu);
 339	kmem_cache_free(ntfs_big_inode_cache, NTFS_I(inode));
 340}
 341
 342void ntfs_destroy_big_inode(struct inode *inode)
 343{
 344	ntfs_inode *ni = NTFS_I(inode);
 345
 346	ntfs_debug("Entering.");
 347	BUG_ON(ni->page);
 348	if (!atomic_dec_and_test(&ni->count))
 349		BUG();
 350	call_rcu(&inode->i_rcu, ntfs_i_callback);
 351}
 352
 353static inline ntfs_inode *ntfs_alloc_extent_inode(void)
 354{
 355	ntfs_inode *ni;
 356
 357	ntfs_debug("Entering.");
 358	ni = kmem_cache_alloc(ntfs_inode_cache, GFP_NOFS);
 359	if (likely(ni != NULL)) {
 360		ni->state = 0;
 361		return ni;
 362	}
 363	ntfs_error(NULL, "Allocation of NTFS inode structure failed.");
 364	return NULL;
 365}
 366
 367static void ntfs_destroy_extent_inode(ntfs_inode *ni)
 368{
 369	ntfs_debug("Entering.");
 370	BUG_ON(ni->page);
 371	if (!atomic_dec_and_test(&ni->count))
 372		BUG();
 373	kmem_cache_free(ntfs_inode_cache, ni);
 374}
 375
 376/*
 377 * The attribute runlist lock has separate locking rules from the
 378 * normal runlist lock, so split the two lock-classes:
 379 */
 380static struct lock_class_key attr_list_rl_lock_class;
 381
 382/**
 383 * __ntfs_init_inode - initialize ntfs specific part of an inode
 384 * @sb:		super block of mounted volume
 385 * @ni:		freshly allocated ntfs inode which to initialize
 386 *
 387 * Initialize an ntfs inode to defaults.
 388 *
 389 * NOTE: ni->mft_no, ni->state, ni->type, ni->name, and ni->name_len are left
 390 * untouched. Make sure to initialize them elsewhere.
 391 *
 392 * Return zero on success and -ENOMEM on error.
 393 */
 394void __ntfs_init_inode(struct super_block *sb, ntfs_inode *ni)
 395{
 396	ntfs_debug("Entering.");
 397	rwlock_init(&ni->size_lock);
 398	ni->initialized_size = ni->allocated_size = 0;
 399	ni->seq_no = 0;
 400	atomic_set(&ni->count, 1);
 401	ni->vol = NTFS_SB(sb);
 402	ntfs_init_runlist(&ni->runlist);
 403	mutex_init(&ni->mrec_lock);
 404	ni->page = NULL;
 405	ni->page_ofs = 0;
 406	ni->attr_list_size = 0;
 407	ni->attr_list = NULL;
 408	ntfs_init_runlist(&ni->attr_list_rl);
 409	lockdep_set_class(&ni->attr_list_rl.lock,
 410				&attr_list_rl_lock_class);
 411	ni->itype.index.block_size = 0;
 412	ni->itype.index.vcn_size = 0;
 413	ni->itype.index.collation_rule = 0;
 414	ni->itype.index.block_size_bits = 0;
 415	ni->itype.index.vcn_size_bits = 0;
 416	mutex_init(&ni->extent_lock);
 417	ni->nr_extents = 0;
 418	ni->ext.base_ntfs_ino = NULL;
 419}
 420
 421/*
 422 * Extent inodes get MFT-mapped in a nested way, while the base inode
 423 * is still mapped. Teach this nesting to the lock validator by creating
 424 * a separate class for nested inode's mrec_lock's:
 425 */
 426static struct lock_class_key extent_inode_mrec_lock_key;
 427
 428inline ntfs_inode *ntfs_new_extent_inode(struct super_block *sb,
 429		unsigned long mft_no)
 430{
 431	ntfs_inode *ni = ntfs_alloc_extent_inode();
 432
 433	ntfs_debug("Entering.");
 434	if (likely(ni != NULL)) {
 435		__ntfs_init_inode(sb, ni);
 436		lockdep_set_class(&ni->mrec_lock, &extent_inode_mrec_lock_key);
 437		ni->mft_no = mft_no;
 438		ni->type = AT_UNUSED;
 439		ni->name = NULL;
 440		ni->name_len = 0;
 441	}
 442	return ni;
 443}
 444
 445/**
 446 * ntfs_is_extended_system_file - check if a file is in the $Extend directory
 447 * @ctx:	initialized attribute search context
 448 *
 449 * Search all file name attributes in the inode described by the attribute
 450 * search context @ctx and check if any of the names are in the $Extend system
 451 * directory.
 452 *
 453 * Return values:
 454 *	   1: file is in $Extend directory
 455 *	   0: file is not in $Extend directory
 456 *    -errno: failed to determine if the file is in the $Extend directory
 457 */
 458static int ntfs_is_extended_system_file(ntfs_attr_search_ctx *ctx)
 459{
 460	int nr_links, err;
 461
 462	/* Restart search. */
 463	ntfs_attr_reinit_search_ctx(ctx);
 464
 465	/* Get number of hard links. */
 466	nr_links = le16_to_cpu(ctx->mrec->link_count);
 467
 468	/* Loop through all hard links. */
 469	while (!(err = ntfs_attr_lookup(AT_FILE_NAME, NULL, 0, 0, 0, NULL, 0,
 470			ctx))) {
 471		FILE_NAME_ATTR *file_name_attr;
 472		ATTR_RECORD *attr = ctx->attr;
 473		u8 *p, *p2;
 474
 475		nr_links--;
 476		/*
 477		 * Maximum sanity checking as we are called on an inode that
 478		 * we suspect might be corrupt.
 479		 */
 480		p = (u8*)attr + le32_to_cpu(attr->length);
 481		if (p < (u8*)ctx->mrec || (u8*)p > (u8*)ctx->mrec +
 482				le32_to_cpu(ctx->mrec->bytes_in_use)) {
 483err_corrupt_attr:
 484			ntfs_error(ctx->ntfs_ino->vol->sb, "Corrupt file name "
 485					"attribute. You should run chkdsk.");
 486			return -EIO;
 487		}
 488		if (attr->non_resident) {
 489			ntfs_error(ctx->ntfs_ino->vol->sb, "Non-resident file "
 490					"name. You should run chkdsk.");
 491			return -EIO;
 492		}
 493		if (attr->flags) {
 494			ntfs_error(ctx->ntfs_ino->vol->sb, "File name with "
 495					"invalid flags. You should run "
 496					"chkdsk.");
 497			return -EIO;
 498		}
 499		if (!(attr->data.resident.flags & RESIDENT_ATTR_IS_INDEXED)) {
 500			ntfs_error(ctx->ntfs_ino->vol->sb, "Unindexed file "
 501					"name. You should run chkdsk.");
 502			return -EIO;
 503		}
 504		file_name_attr = (FILE_NAME_ATTR*)((u8*)attr +
 505				le16_to_cpu(attr->data.resident.value_offset));
 506		p2 = (u8*)attr + le32_to_cpu(attr->data.resident.value_length);
 507		if (p2 < (u8*)attr || p2 > p)
 508			goto err_corrupt_attr;
 509		/* This attribute is ok, but is it in the $Extend directory? */
 510		if (MREF_LE(file_name_attr->parent_directory) == FILE_Extend)
 511			return 1;	/* YES, it's an extended system file. */
 512	}
 513	if (unlikely(err != -ENOENT))
 514		return err;
 515	if (unlikely(nr_links)) {
 516		ntfs_error(ctx->ntfs_ino->vol->sb, "Inode hard link count "
 517				"doesn't match number of name attributes. You "
 518				"should run chkdsk.");
 519		return -EIO;
 520	}
 521	return 0;	/* NO, it is not an extended system file. */
 522}
 523
 524/**
 525 * ntfs_read_locked_inode - read an inode from its device
 526 * @vi:		inode to read
 527 *
 528 * ntfs_read_locked_inode() is called from ntfs_iget() to read the inode
 529 * described by @vi into memory from the device.
 530 *
 531 * The only fields in @vi that we need to/can look at when the function is
 532 * called are i_sb, pointing to the mounted device's super block, and i_ino,
 533 * the number of the inode to load.
 534 *
 535 * ntfs_read_locked_inode() maps, pins and locks the mft record number i_ino
 536 * for reading and sets up the necessary @vi fields as well as initializing
 537 * the ntfs inode.
 538 *
 539 * Q: What locks are held when the function is called?
 540 * A: i_state has I_NEW set, hence the inode is locked, also
 541 *    i_count is set to 1, so it is not going to go away
 542 *    i_flags is set to 0 and we have no business touching it.  Only an ioctl()
 543 *    is allowed to write to them. We should of course be honouring them but
 544 *    we need to do that using the IS_* macros defined in include/linux/fs.h.
 545 *    In any case ntfs_read_locked_inode() has nothing to do with i_flags.
 546 *
 547 * Return 0 on success and -errno on error.  In the error case, the inode will
 548 * have had make_bad_inode() executed on it.
 549 */
 550static int ntfs_read_locked_inode(struct inode *vi)
 551{
 552	ntfs_volume *vol = NTFS_SB(vi->i_sb);
 553	ntfs_inode *ni;
 554	struct inode *bvi;
 555	MFT_RECORD *m;
 556	ATTR_RECORD *a;
 557	STANDARD_INFORMATION *si;
 558	ntfs_attr_search_ctx *ctx;
 559	int err = 0;
 560
 561	ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
 562
 563	/* Setup the generic vfs inode parts now. */
 564
 565	/*
 566	 * This is for checking whether an inode has changed w.r.t. a file so
 567	 * that the file can be updated if necessary (compare with f_version).
 568	 */
 569	vi->i_version = 1;
 570
 571	vi->i_uid = vol->uid;
 572	vi->i_gid = vol->gid;
 573	vi->i_mode = 0;
 574
 575	/*
 576	 * Initialize the ntfs specific part of @vi special casing
 577	 * FILE_MFT which we need to do at mount time.
 578	 */
 579	if (vi->i_ino != FILE_MFT)
 580		ntfs_init_big_inode(vi);
 581	ni = NTFS_I(vi);
 582
 583	m = map_mft_record(ni);
 584	if (IS_ERR(m)) {
 585		err = PTR_ERR(m);
 586		goto err_out;
 587	}
 588	ctx = ntfs_attr_get_search_ctx(ni, m);
 589	if (!ctx) {
 590		err = -ENOMEM;
 591		goto unm_err_out;
 592	}
 593
 594	if (!(m->flags & MFT_RECORD_IN_USE)) {
 595		ntfs_error(vi->i_sb, "Inode is not in use!");
 596		goto unm_err_out;
 597	}
 598	if (m->base_mft_record) {
 599		ntfs_error(vi->i_sb, "Inode is an extent inode!");
 600		goto unm_err_out;
 601	}
 602
 603	/* Transfer information from mft record into vfs and ntfs inodes. */
 604	vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);
 605
 606	/*
 607	 * FIXME: Keep in mind that link_count is two for files which have both
 608	 * a long file name and a short file name as separate entries, so if
 609	 * we are hiding short file names this will be too high. Either we need
 610	 * to account for the short file names by subtracting them or we need
 611	 * to make sure we delete files even though i_nlink is not zero which
 612	 * might be tricky due to vfs interactions. Need to think about this
 613	 * some more when implementing the unlink command.
 614	 */
 615	set_nlink(vi, le16_to_cpu(m->link_count));
 616	/*
 617	 * FIXME: Reparse points can have the directory bit set even though
 618	 * they would be S_IFLNK. Need to deal with this further below when we
 619	 * implement reparse points / symbolic links but it will do for now.
 620	 * Also if not a directory, it could be something else, rather than
 621	 * a regular file. But again, will do for now.
 622	 */
 623	/* Everyone gets all permissions. */
 624	vi->i_mode |= S_IRWXUGO;
 625	/* If read-only, no one gets write permissions. */
 626	if (IS_RDONLY(vi))
 627		vi->i_mode &= ~S_IWUGO;
 628	if (m->flags & MFT_RECORD_IS_DIRECTORY) {
 629		vi->i_mode |= S_IFDIR;
 630		/*
 631		 * Apply the directory permissions mask set in the mount
 632		 * options.
 633		 */
 634		vi->i_mode &= ~vol->dmask;
 635		/* Things break without this kludge! */
 636		if (vi->i_nlink > 1)
 637			set_nlink(vi, 1);
 638	} else {
 639		vi->i_mode |= S_IFREG;
 640		/* Apply the file permissions mask set in the mount options. */
 641		vi->i_mode &= ~vol->fmask;
 642	}
 643	/*
 644	 * Find the standard information attribute in the mft record. At this
 645	 * stage we haven't setup the attribute list stuff yet, so this could
 646	 * in fact fail if the standard information is in an extent record, but
 647	 * I don't think this actually ever happens.
 648	 */
 649	err = ntfs_attr_lookup(AT_STANDARD_INFORMATION, NULL, 0, 0, 0, NULL, 0,
 650			ctx);
 651	if (unlikely(err)) {
 652		if (err == -ENOENT) {
 653			/*
 654			 * TODO: We should be performing a hot fix here (if the
 655			 * recover mount option is set) by creating a new
 656			 * attribute.
 657			 */
 658			ntfs_error(vi->i_sb, "$STANDARD_INFORMATION attribute "
 659					"is missing.");
 660		}
 661		goto unm_err_out;
 662	}
 663	a = ctx->attr;
 664	/* Get the standard information attribute value. */
 665	si = (STANDARD_INFORMATION*)((u8*)a +
 666			le16_to_cpu(a->data.resident.value_offset));
 667
 668	/* Transfer information from the standard information into vi. */
 669	/*
 670	 * Note: The i_?times do not quite map perfectly onto the NTFS times,
 671	 * but they are close enough, and in the end it doesn't really matter
 672	 * that much...
 673	 */
 674	/*
 675	 * mtime is the last change of the data within the file. Not changed
 676	 * when only metadata is changed, e.g. a rename doesn't affect mtime.
 677	 */
 678	vi->i_mtime = ntfs2utc(si->last_data_change_time);
 679	/*
 680	 * ctime is the last change of the metadata of the file. This obviously
 681	 * always changes, when mtime is changed. ctime can be changed on its
 682	 * own, mtime is then not changed, e.g. when a file is renamed.
 683	 */
 684	vi->i_ctime = ntfs2utc(si->last_mft_change_time);
 685	/*
 686	 * Last access to the data within the file. Not changed during a rename
 687	 * for example but changed whenever the file is written to.
 688	 */
 689	vi->i_atime = ntfs2utc(si->last_access_time);
 690
 691	/* Find the attribute list attribute if present. */
 692	ntfs_attr_reinit_search_ctx(ctx);
 693	err = ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, 0, 0, NULL, 0, ctx);
 694	if (err) {
 695		if (unlikely(err != -ENOENT)) {
 696			ntfs_error(vi->i_sb, "Failed to lookup attribute list "
 697					"attribute.");
 698			goto unm_err_out;
 699		}
 700	} else /* if (!err) */ {
 701		if (vi->i_ino == FILE_MFT)
 702			goto skip_attr_list_load;
 703		ntfs_debug("Attribute list found in inode 0x%lx.", vi->i_ino);
 704		NInoSetAttrList(ni);
 705		a = ctx->attr;
 706		if (a->flags & ATTR_COMPRESSION_MASK) {
 707			ntfs_error(vi->i_sb, "Attribute list attribute is "
 708					"compressed.");
 709			goto unm_err_out;
 710		}
 711		if (a->flags & ATTR_IS_ENCRYPTED ||
 712				a->flags & ATTR_IS_SPARSE) {
 713			if (a->non_resident) {
 714				ntfs_error(vi->i_sb, "Non-resident attribute "
 715						"list attribute is encrypted/"
 716						"sparse.");
 717				goto unm_err_out;
 718			}
 719			ntfs_warning(vi->i_sb, "Resident attribute list "
 720					"attribute in inode 0x%lx is marked "
 721					"encrypted/sparse which is not true.  "
 722					"However, Windows allows this and "
 723					"chkdsk does not detect or correct it "
 724					"so we will just ignore the invalid "
 725					"flags and pretend they are not set.",
 726					vi->i_ino);
 727		}
 728		/* Now allocate memory for the attribute list. */
 729		ni->attr_list_size = (u32)ntfs_attr_size(a);
 730		ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
 731		if (!ni->attr_list) {
 732			ntfs_error(vi->i_sb, "Not enough memory to allocate "
 733					"buffer for attribute list.");
 734			err = -ENOMEM;
 735			goto unm_err_out;
 736		}
 737		if (a->non_resident) {
 738			NInoSetAttrListNonResident(ni);
 739			if (a->data.non_resident.lowest_vcn) {
 740				ntfs_error(vi->i_sb, "Attribute list has non "
 741						"zero lowest_vcn.");
 742				goto unm_err_out;
 743			}
 744			/*
 745			 * Setup the runlist. No need for locking as we have
 746			 * exclusive access to the inode at this time.
 747			 */
 748			ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
 749					a, NULL);
 750			if (IS_ERR(ni->attr_list_rl.rl)) {
 751				err = PTR_ERR(ni->attr_list_rl.rl);
 752				ni->attr_list_rl.rl = NULL;
 753				ntfs_error(vi->i_sb, "Mapping pairs "
 754						"decompression failed.");
 755				goto unm_err_out;
 756			}
 757			/* Now load the attribute list. */
 758			if ((err = load_attribute_list(vol, &ni->attr_list_rl,
 759					ni->attr_list, ni->attr_list_size,
 760					sle64_to_cpu(a->data.non_resident.
 761					initialized_size)))) {
 762				ntfs_error(vi->i_sb, "Failed to load "
 763						"attribute list attribute.");
 764				goto unm_err_out;
 765			}
 766		} else /* if (!a->non_resident) */ {
 767			if ((u8*)a + le16_to_cpu(a->data.resident.value_offset)
 768					+ le32_to_cpu(
 769					a->data.resident.value_length) >
 770					(u8*)ctx->mrec + vol->mft_record_size) {
 771				ntfs_error(vi->i_sb, "Corrupt attribute list "
 772						"in inode.");
 773				goto unm_err_out;
 774			}
 775			/* Now copy the attribute list. */
 776			memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
 777					a->data.resident.value_offset),
 778					le32_to_cpu(
 779					a->data.resident.value_length));
 780		}
 781	}
 782skip_attr_list_load:
 783	/*
 784	 * If an attribute list is present we now have the attribute list value
 785	 * in ntfs_ino->attr_list and it is ntfs_ino->attr_list_size bytes.
 786	 */
 787	if (S_ISDIR(vi->i_mode)) {
 788		loff_t bvi_size;
 789		ntfs_inode *bni;
 790		INDEX_ROOT *ir;
 791		u8 *ir_end, *index_end;
 792
 793		/* It is a directory, find index root attribute. */
 794		ntfs_attr_reinit_search_ctx(ctx);
 795		err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE,
 796				0, NULL, 0, ctx);
 797		if (unlikely(err)) {
 798			if (err == -ENOENT) {
 799				// FIXME: File is corrupt! Hot-fix with empty
 800				// index root attribute if recovery option is
 801				// set.
 802				ntfs_error(vi->i_sb, "$INDEX_ROOT attribute "
 803						"is missing.");
 804			}
 805			goto unm_err_out;
 806		}
 807		a = ctx->attr;
 808		/* Set up the state. */
 809		if (unlikely(a->non_resident)) {
 810			ntfs_error(vol->sb, "$INDEX_ROOT attribute is not "
 811					"resident.");
 812			goto unm_err_out;
 813		}
 814		/* Ensure the attribute name is placed before the value. */
 815		if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
 816				le16_to_cpu(a->data.resident.value_offset)))) {
 817			ntfs_error(vol->sb, "$INDEX_ROOT attribute name is "
 818					"placed after the attribute value.");
 819			goto unm_err_out;
 820		}
 821		/*
 822		 * Compressed/encrypted index root just means that the newly
 823		 * created files in that directory should be created compressed/
 824		 * encrypted. However index root cannot be both compressed and
 825		 * encrypted.
 826		 */
 827		if (a->flags & ATTR_COMPRESSION_MASK)
 828			NInoSetCompressed(ni);
 829		if (a->flags & ATTR_IS_ENCRYPTED) {
 830			if (a->flags & ATTR_COMPRESSION_MASK) {
 831				ntfs_error(vi->i_sb, "Found encrypted and "
 832						"compressed attribute.");
 833				goto unm_err_out;
 834			}
 835			NInoSetEncrypted(ni);
 836		}
 837		if (a->flags & ATTR_IS_SPARSE)
 838			NInoSetSparse(ni);
 839		ir = (INDEX_ROOT*)((u8*)a +
 840				le16_to_cpu(a->data.resident.value_offset));
 841		ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
 842		if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
 843			ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
 844					"corrupt.");
 845			goto unm_err_out;
 846		}
 847		index_end = (u8*)&ir->index +
 848				le32_to_cpu(ir->index.index_length);
 849		if (index_end > ir_end) {
 850			ntfs_error(vi->i_sb, "Directory index is corrupt.");
 851			goto unm_err_out;
 852		}
 853		if (ir->type != AT_FILE_NAME) {
 854			ntfs_error(vi->i_sb, "Indexed attribute is not "
 855					"$FILE_NAME.");
 856			goto unm_err_out;
 857		}
 858		if (ir->collation_rule != COLLATION_FILE_NAME) {
 859			ntfs_error(vi->i_sb, "Index collation rule is not "
 860					"COLLATION_FILE_NAME.");
 861			goto unm_err_out;
 862		}
 863		ni->itype.index.collation_rule = ir->collation_rule;
 864		ni->itype.index.block_size = le32_to_cpu(ir->index_block_size);
 865		if (ni->itype.index.block_size &
 866				(ni->itype.index.block_size - 1)) {
 867			ntfs_error(vi->i_sb, "Index block size (%u) is not a "
 868					"power of two.",
 869					ni->itype.index.block_size);
 870			goto unm_err_out;
 871		}
 872		if (ni->itype.index.block_size > PAGE_CACHE_SIZE) {
 873			ntfs_error(vi->i_sb, "Index block size (%u) > "
 874					"PAGE_CACHE_SIZE (%ld) is not "
 875					"supported.  Sorry.",
 876					ni->itype.index.block_size,
 877					PAGE_CACHE_SIZE);
 878			err = -EOPNOTSUPP;
 879			goto unm_err_out;
 880		}
 881		if (ni->itype.index.block_size < NTFS_BLOCK_SIZE) {
 882			ntfs_error(vi->i_sb, "Index block size (%u) < "
 883					"NTFS_BLOCK_SIZE (%i) is not "
 884					"supported.  Sorry.",
 885					ni->itype.index.block_size,
 886					NTFS_BLOCK_SIZE);
 887			err = -EOPNOTSUPP;
 888			goto unm_err_out;
 889		}
 890		ni->itype.index.block_size_bits =
 891				ffs(ni->itype.index.block_size) - 1;
 892		/* Determine the size of a vcn in the directory index. */
 893		if (vol->cluster_size <= ni->itype.index.block_size) {
 894			ni->itype.index.vcn_size = vol->cluster_size;
 895			ni->itype.index.vcn_size_bits = vol->cluster_size_bits;
 896		} else {
 897			ni->itype.index.vcn_size = vol->sector_size;
 898			ni->itype.index.vcn_size_bits = vol->sector_size_bits;
 899		}
 900
 901		/* Setup the index allocation attribute, even if not present. */
 902		NInoSetMstProtected(ni);
 903		ni->type = AT_INDEX_ALLOCATION;
 904		ni->name = I30;
 905		ni->name_len = 4;
 906
 907		if (!(ir->index.flags & LARGE_INDEX)) {
 908			/* No index allocation. */
 909			vi->i_size = ni->initialized_size =
 910					ni->allocated_size = 0;
 911			/* We are done with the mft record, so we release it. */
 912			ntfs_attr_put_search_ctx(ctx);
 913			unmap_mft_record(ni);
 914			m = NULL;
 915			ctx = NULL;
 916			goto skip_large_dir_stuff;
 917		} /* LARGE_INDEX: Index allocation present. Setup state. */
 918		NInoSetIndexAllocPresent(ni);
 919		/* Find index allocation attribute. */
 920		ntfs_attr_reinit_search_ctx(ctx);
 921		err = ntfs_attr_lookup(AT_INDEX_ALLOCATION, I30, 4,
 922				CASE_SENSITIVE, 0, NULL, 0, ctx);
 923		if (unlikely(err)) {
 924			if (err == -ENOENT)
 925				ntfs_error(vi->i_sb, "$INDEX_ALLOCATION "
 926						"attribute is not present but "
 927						"$INDEX_ROOT indicated it is.");
 928			else
 929				ntfs_error(vi->i_sb, "Failed to lookup "
 930						"$INDEX_ALLOCATION "
 931						"attribute.");
 932			goto unm_err_out;
 933		}
 934		a = ctx->attr;
 935		if (!a->non_resident) {
 936			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 937					"is resident.");
 938			goto unm_err_out;
 939		}
 940		/*
 941		 * Ensure the attribute name is placed before the mapping pairs
 942		 * array.
 943		 */
 944		if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
 945				le16_to_cpu(
 946				a->data.non_resident.mapping_pairs_offset)))) {
 947			ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name "
 948					"is placed after the mapping pairs "
 949					"array.");
 950			goto unm_err_out;
 951		}
 952		if (a->flags & ATTR_IS_ENCRYPTED) {
 953			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 954					"is encrypted.");
 955			goto unm_err_out;
 956		}
 957		if (a->flags & ATTR_IS_SPARSE) {
 958			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 959					"is sparse.");
 960			goto unm_err_out;
 961		}
 962		if (a->flags & ATTR_COMPRESSION_MASK) {
 963			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 964					"is compressed.");
 965			goto unm_err_out;
 966		}
 967		if (a->data.non_resident.lowest_vcn) {
 968			ntfs_error(vi->i_sb, "First extent of "
 969					"$INDEX_ALLOCATION attribute has non "
 970					"zero lowest_vcn.");
 971			goto unm_err_out;
 972		}
 973		vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
 974		ni->initialized_size = sle64_to_cpu(
 975				a->data.non_resident.initialized_size);
 976		ni->allocated_size = sle64_to_cpu(
 977				a->data.non_resident.allocated_size);
 978		/*
 979		 * We are done with the mft record, so we release it. Otherwise
 980		 * we would deadlock in ntfs_attr_iget().
 981		 */
 982		ntfs_attr_put_search_ctx(ctx);
 983		unmap_mft_record(ni);
 984		m = NULL;
 985		ctx = NULL;
 986		/* Get the index bitmap attribute inode. */
 987		bvi = ntfs_attr_iget(vi, AT_BITMAP, I30, 4);
 988		if (IS_ERR(bvi)) {
 989			ntfs_error(vi->i_sb, "Failed to get bitmap attribute.");
 990			err = PTR_ERR(bvi);
 991			goto unm_err_out;
 992		}
 993		bni = NTFS_I(bvi);
 994		if (NInoCompressed(bni) || NInoEncrypted(bni) ||
 995				NInoSparse(bni)) {
 996			ntfs_error(vi->i_sb, "$BITMAP attribute is compressed "
 997					"and/or encrypted and/or sparse.");
 998			goto iput_unm_err_out;
 999		}
1000		/* Consistency check bitmap size vs. index allocation size. */
1001		bvi_size = i_size_read(bvi);
1002		if ((bvi_size << 3) < (vi->i_size >>
1003				ni->itype.index.block_size_bits)) {
1004			ntfs_error(vi->i_sb, "Index bitmap too small (0x%llx) "
1005					"for index allocation (0x%llx).",
1006					bvi_size << 3, vi->i_size);
1007			goto iput_unm_err_out;
1008		}
1009		/* No longer need the bitmap attribute inode. */
1010		iput(bvi);
1011skip_large_dir_stuff:
1012		/* Setup the operations for this inode. */
1013		vi->i_op = &ntfs_dir_inode_ops;
1014		vi->i_fop = &ntfs_dir_ops;
 
1015	} else {
1016		/* It is a file. */
1017		ntfs_attr_reinit_search_ctx(ctx);
1018
1019		/* Setup the data attribute, even if not present. */
1020		ni->type = AT_DATA;
1021		ni->name = NULL;
1022		ni->name_len = 0;
1023
1024		/* Find first extent of the unnamed data attribute. */
1025		err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, 0, NULL, 0, ctx);
1026		if (unlikely(err)) {
1027			vi->i_size = ni->initialized_size =
1028					ni->allocated_size = 0;
1029			if (err != -ENOENT) {
1030				ntfs_error(vi->i_sb, "Failed to lookup $DATA "
1031						"attribute.");
1032				goto unm_err_out;
1033			}
1034			/*
1035			 * FILE_Secure does not have an unnamed $DATA
1036			 * attribute, so we special case it here.
1037			 */
1038			if (vi->i_ino == FILE_Secure)
1039				goto no_data_attr_special_case;
1040			/*
1041			 * Most if not all the system files in the $Extend
1042			 * system directory do not have unnamed data
1043			 * attributes so we need to check if the parent
1044			 * directory of the file is FILE_Extend and if it is
1045			 * ignore this error. To do this we need to get the
1046			 * name of this inode from the mft record as the name
1047			 * contains the back reference to the parent directory.
1048			 */
1049			if (ntfs_is_extended_system_file(ctx) > 0)
1050				goto no_data_attr_special_case;
1051			// FIXME: File is corrupt! Hot-fix with empty data
1052			// attribute if recovery option is set.
1053			ntfs_error(vi->i_sb, "$DATA attribute is missing.");
1054			goto unm_err_out;
1055		}
1056		a = ctx->attr;
1057		/* Setup the state. */
1058		if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) {
1059			if (a->flags & ATTR_COMPRESSION_MASK) {
1060				NInoSetCompressed(ni);
1061				if (vol->cluster_size > 4096) {
1062					ntfs_error(vi->i_sb, "Found "
1063							"compressed data but "
1064							"compression is "
1065							"disabled due to "
1066							"cluster size (%i) > "
1067							"4kiB.",
1068							vol->cluster_size);
1069					goto unm_err_out;
1070				}
1071				if ((a->flags & ATTR_COMPRESSION_MASK)
1072						!= ATTR_IS_COMPRESSED) {
1073					ntfs_error(vi->i_sb, "Found unknown "
1074							"compression method "
1075							"or corrupt file.");
1076					goto unm_err_out;
1077				}
1078			}
1079			if (a->flags & ATTR_IS_SPARSE)
1080				NInoSetSparse(ni);
1081		}
1082		if (a->flags & ATTR_IS_ENCRYPTED) {
1083			if (NInoCompressed(ni)) {
1084				ntfs_error(vi->i_sb, "Found encrypted and "
1085						"compressed data.");
1086				goto unm_err_out;
1087			}
1088			NInoSetEncrypted(ni);
1089		}
1090		if (a->non_resident) {
1091			NInoSetNonResident(ni);
1092			if (NInoCompressed(ni) || NInoSparse(ni)) {
1093				if (NInoCompressed(ni) && a->data.non_resident.
1094						compression_unit != 4) {
1095					ntfs_error(vi->i_sb, "Found "
1096							"non-standard "
1097							"compression unit (%u "
1098							"instead of 4).  "
1099							"Cannot handle this.",
1100							a->data.non_resident.
1101							compression_unit);
1102					err = -EOPNOTSUPP;
1103					goto unm_err_out;
1104				}
1105				if (a->data.non_resident.compression_unit) {
1106					ni->itype.compressed.block_size = 1U <<
1107							(a->data.non_resident.
1108							compression_unit +
1109							vol->cluster_size_bits);
1110					ni->itype.compressed.block_size_bits =
1111							ffs(ni->itype.
1112							compressed.
1113							block_size) - 1;
1114					ni->itype.compressed.block_clusters =
1115							1U << a->data.
1116							non_resident.
1117							compression_unit;
1118				} else {
1119					ni->itype.compressed.block_size = 0;
1120					ni->itype.compressed.block_size_bits =
1121							0;
1122					ni->itype.compressed.block_clusters =
1123							0;
1124				}
1125				ni->itype.compressed.size = sle64_to_cpu(
1126						a->data.non_resident.
1127						compressed_size);
1128			}
1129			if (a->data.non_resident.lowest_vcn) {
1130				ntfs_error(vi->i_sb, "First extent of $DATA "
1131						"attribute has non zero "
1132						"lowest_vcn.");
1133				goto unm_err_out;
1134			}
1135			vi->i_size = sle64_to_cpu(
1136					a->data.non_resident.data_size);
1137			ni->initialized_size = sle64_to_cpu(
1138					a->data.non_resident.initialized_size);
1139			ni->allocated_size = sle64_to_cpu(
1140					a->data.non_resident.allocated_size);
1141		} else { /* Resident attribute. */
1142			vi->i_size = ni->initialized_size = le32_to_cpu(
1143					a->data.resident.value_length);
1144			ni->allocated_size = le32_to_cpu(a->length) -
1145					le16_to_cpu(
1146					a->data.resident.value_offset);
1147			if (vi->i_size > ni->allocated_size) {
1148				ntfs_error(vi->i_sb, "Resident data attribute "
1149						"is corrupt (size exceeds "
1150						"allocation).");
1151				goto unm_err_out;
1152			}
1153		}
1154no_data_attr_special_case:
1155		/* We are done with the mft record, so we release it. */
1156		ntfs_attr_put_search_ctx(ctx);
1157		unmap_mft_record(ni);
1158		m = NULL;
1159		ctx = NULL;
1160		/* Setup the operations for this inode. */
1161		vi->i_op = &ntfs_file_inode_ops;
1162		vi->i_fop = &ntfs_file_ops;
 
 
 
 
 
1163	}
1164	if (NInoMstProtected(ni))
1165		vi->i_mapping->a_ops = &ntfs_mst_aops;
1166	else
1167		vi->i_mapping->a_ops = &ntfs_aops;
1168	/*
1169	 * The number of 512-byte blocks used on disk (for stat). This is in so
1170	 * far inaccurate as it doesn't account for any named streams or other
1171	 * special non-resident attributes, but that is how Windows works, too,
1172	 * so we are at least consistent with Windows, if not entirely
1173	 * consistent with the Linux Way. Doing it the Linux Way would cause a
1174	 * significant slowdown as it would involve iterating over all
1175	 * attributes in the mft record and adding the allocated/compressed
1176	 * sizes of all non-resident attributes present to give us the Linux
1177	 * correct size that should go into i_blocks (after division by 512).
1178	 */
1179	if (S_ISREG(vi->i_mode) && (NInoCompressed(ni) || NInoSparse(ni)))
1180		vi->i_blocks = ni->itype.compressed.size >> 9;
1181	else
1182		vi->i_blocks = ni->allocated_size >> 9;
1183	ntfs_debug("Done.");
1184	return 0;
1185iput_unm_err_out:
1186	iput(bvi);
1187unm_err_out:
1188	if (!err)
1189		err = -EIO;
1190	if (ctx)
1191		ntfs_attr_put_search_ctx(ctx);
1192	if (m)
1193		unmap_mft_record(ni);
1194err_out:
1195	ntfs_error(vol->sb, "Failed with error code %i.  Marking corrupt "
1196			"inode 0x%lx as bad.  Run chkdsk.", err, vi->i_ino);
1197	make_bad_inode(vi);
1198	if (err != -EOPNOTSUPP && err != -ENOMEM)
1199		NVolSetErrors(vol);
1200	return err;
1201}
1202
1203/**
1204 * ntfs_read_locked_attr_inode - read an attribute inode from its base inode
1205 * @base_vi:	base inode
1206 * @vi:		attribute inode to read
1207 *
1208 * ntfs_read_locked_attr_inode() is called from ntfs_attr_iget() to read the
1209 * attribute inode described by @vi into memory from the base mft record
1210 * described by @base_ni.
1211 *
1212 * ntfs_read_locked_attr_inode() maps, pins and locks the base inode for
1213 * reading and looks up the attribute described by @vi before setting up the
1214 * necessary fields in @vi as well as initializing the ntfs inode.
1215 *
1216 * Q: What locks are held when the function is called?
1217 * A: i_state has I_NEW set, hence the inode is locked, also
1218 *    i_count is set to 1, so it is not going to go away
1219 *
1220 * Return 0 on success and -errno on error.  In the error case, the inode will
1221 * have had make_bad_inode() executed on it.
1222 *
1223 * Note this cannot be called for AT_INDEX_ALLOCATION.
1224 */
1225static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi)
1226{
1227	ntfs_volume *vol = NTFS_SB(vi->i_sb);
1228	ntfs_inode *ni, *base_ni;
1229	MFT_RECORD *m;
1230	ATTR_RECORD *a;
1231	ntfs_attr_search_ctx *ctx;
1232	int err = 0;
1233
1234	ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
1235
1236	ntfs_init_big_inode(vi);
1237
1238	ni	= NTFS_I(vi);
1239	base_ni = NTFS_I(base_vi);
1240
1241	/* Just mirror the values from the base inode. */
1242	vi->i_version	= base_vi->i_version;
1243	vi->i_uid	= base_vi->i_uid;
1244	vi->i_gid	= base_vi->i_gid;
1245	set_nlink(vi, base_vi->i_nlink);
1246	vi->i_mtime	= base_vi->i_mtime;
1247	vi->i_ctime	= base_vi->i_ctime;
1248	vi->i_atime	= base_vi->i_atime;
1249	vi->i_generation = ni->seq_no = base_ni->seq_no;
1250
1251	/* Set inode type to zero but preserve permissions. */
1252	vi->i_mode	= base_vi->i_mode & ~S_IFMT;
1253
1254	m = map_mft_record(base_ni);
1255	if (IS_ERR(m)) {
1256		err = PTR_ERR(m);
1257		goto err_out;
1258	}
1259	ctx = ntfs_attr_get_search_ctx(base_ni, m);
1260	if (!ctx) {
1261		err = -ENOMEM;
1262		goto unm_err_out;
1263	}
1264	/* Find the attribute. */
1265	err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
1266			CASE_SENSITIVE, 0, NULL, 0, ctx);
1267	if (unlikely(err))
1268		goto unm_err_out;
1269	a = ctx->attr;
1270	if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) {
1271		if (a->flags & ATTR_COMPRESSION_MASK) {
1272			NInoSetCompressed(ni);
1273			if ((ni->type != AT_DATA) || (ni->type == AT_DATA &&
1274					ni->name_len)) {
1275				ntfs_error(vi->i_sb, "Found compressed "
1276						"non-data or named data "
1277						"attribute.  Please report "
1278						"you saw this message to "
1279						"linux-ntfs-dev@lists."
1280						"sourceforge.net");
1281				goto unm_err_out;
1282			}
1283			if (vol->cluster_size > 4096) {
1284				ntfs_error(vi->i_sb, "Found compressed "
1285						"attribute but compression is "
1286						"disabled due to cluster size "
1287						"(%i) > 4kiB.",
1288						vol->cluster_size);
1289				goto unm_err_out;
1290			}
1291			if ((a->flags & ATTR_COMPRESSION_MASK) !=
1292					ATTR_IS_COMPRESSED) {
1293				ntfs_error(vi->i_sb, "Found unknown "
1294						"compression method.");
1295				goto unm_err_out;
1296			}
1297		}
1298		/*
1299		 * The compressed/sparse flag set in an index root just means
1300		 * to compress all files.
1301		 */
1302		if (NInoMstProtected(ni) && ni->type != AT_INDEX_ROOT) {
1303			ntfs_error(vi->i_sb, "Found mst protected attribute "
1304					"but the attribute is %s.  Please "
1305					"report you saw this message to "
1306					"linux-ntfs-dev@lists.sourceforge.net",
1307					NInoCompressed(ni) ? "compressed" :
1308					"sparse");
1309			goto unm_err_out;
1310		}
1311		if (a->flags & ATTR_IS_SPARSE)
1312			NInoSetSparse(ni);
1313	}
1314	if (a->flags & ATTR_IS_ENCRYPTED) {
1315		if (NInoCompressed(ni)) {
1316			ntfs_error(vi->i_sb, "Found encrypted and compressed "
1317					"data.");
1318			goto unm_err_out;
1319		}
1320		/*
1321		 * The encryption flag set in an index root just means to
1322		 * encrypt all files.
1323		 */
1324		if (NInoMstProtected(ni) && ni->type != AT_INDEX_ROOT) {
1325			ntfs_error(vi->i_sb, "Found mst protected attribute "
1326					"but the attribute is encrypted.  "
1327					"Please report you saw this message "
1328					"to linux-ntfs-dev@lists.sourceforge."
1329					"net");
1330			goto unm_err_out;
1331		}
1332		if (ni->type != AT_DATA) {
1333			ntfs_error(vi->i_sb, "Found encrypted non-data "
1334					"attribute.");
1335			goto unm_err_out;
1336		}
1337		NInoSetEncrypted(ni);
1338	}
1339	if (!a->non_resident) {
1340		/* Ensure the attribute name is placed before the value. */
1341		if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1342				le16_to_cpu(a->data.resident.value_offset)))) {
1343			ntfs_error(vol->sb, "Attribute name is placed after "
1344					"the attribute value.");
1345			goto unm_err_out;
1346		}
1347		if (NInoMstProtected(ni)) {
1348			ntfs_error(vi->i_sb, "Found mst protected attribute "
1349					"but the attribute is resident.  "
1350					"Please report you saw this message to "
1351					"linux-ntfs-dev@lists.sourceforge.net");
1352			goto unm_err_out;
1353		}
1354		vi->i_size = ni->initialized_size = le32_to_cpu(
1355				a->data.resident.value_length);
1356		ni->allocated_size = le32_to_cpu(a->length) -
1357				le16_to_cpu(a->data.resident.value_offset);
1358		if (vi->i_size > ni->allocated_size) {
1359			ntfs_error(vi->i_sb, "Resident attribute is corrupt "
1360					"(size exceeds allocation).");
1361			goto unm_err_out;
1362		}
1363	} else {
1364		NInoSetNonResident(ni);
1365		/*
1366		 * Ensure the attribute name is placed before the mapping pairs
1367		 * array.
1368		 */
1369		if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1370				le16_to_cpu(
1371				a->data.non_resident.mapping_pairs_offset)))) {
1372			ntfs_error(vol->sb, "Attribute name is placed after "
1373					"the mapping pairs array.");
1374			goto unm_err_out;
1375		}
1376		if (NInoCompressed(ni) || NInoSparse(ni)) {
1377			if (NInoCompressed(ni) && a->data.non_resident.
1378					compression_unit != 4) {
1379				ntfs_error(vi->i_sb, "Found non-standard "
1380						"compression unit (%u instead "
1381						"of 4).  Cannot handle this.",
1382						a->data.non_resident.
1383						compression_unit);
1384				err = -EOPNOTSUPP;
1385				goto unm_err_out;
1386			}
1387			if (a->data.non_resident.compression_unit) {
1388				ni->itype.compressed.block_size = 1U <<
1389						(a->data.non_resident.
1390						compression_unit +
1391						vol->cluster_size_bits);
1392				ni->itype.compressed.block_size_bits =
1393						ffs(ni->itype.compressed.
1394						block_size) - 1;
1395				ni->itype.compressed.block_clusters = 1U <<
1396						a->data.non_resident.
1397						compression_unit;
1398			} else {
1399				ni->itype.compressed.block_size = 0;
1400				ni->itype.compressed.block_size_bits = 0;
1401				ni->itype.compressed.block_clusters = 0;
1402			}
1403			ni->itype.compressed.size = sle64_to_cpu(
1404					a->data.non_resident.compressed_size);
1405		}
1406		if (a->data.non_resident.lowest_vcn) {
1407			ntfs_error(vi->i_sb, "First extent of attribute has "
1408					"non-zero lowest_vcn.");
1409			goto unm_err_out;
1410		}
1411		vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
1412		ni->initialized_size = sle64_to_cpu(
1413				a->data.non_resident.initialized_size);
1414		ni->allocated_size = sle64_to_cpu(
1415				a->data.non_resident.allocated_size);
1416	}
 
1417	if (NInoMstProtected(ni))
1418		vi->i_mapping->a_ops = &ntfs_mst_aops;
1419	else
1420		vi->i_mapping->a_ops = &ntfs_aops;
1421	if ((NInoCompressed(ni) || NInoSparse(ni)) && ni->type != AT_INDEX_ROOT)
1422		vi->i_blocks = ni->itype.compressed.size >> 9;
1423	else
1424		vi->i_blocks = ni->allocated_size >> 9;
1425	/*
1426	 * Make sure the base inode does not go away and attach it to the
1427	 * attribute inode.
1428	 */
1429	igrab(base_vi);
1430	ni->ext.base_ntfs_ino = base_ni;
1431	ni->nr_extents = -1;
1432
1433	ntfs_attr_put_search_ctx(ctx);
1434	unmap_mft_record(base_ni);
1435
1436	ntfs_debug("Done.");
1437	return 0;
1438
1439unm_err_out:
1440	if (!err)
1441		err = -EIO;
1442	if (ctx)
1443		ntfs_attr_put_search_ctx(ctx);
1444	unmap_mft_record(base_ni);
1445err_out:
1446	ntfs_error(vol->sb, "Failed with error code %i while reading attribute "
1447			"inode (mft_no 0x%lx, type 0x%x, name_len %i).  "
1448			"Marking corrupt inode and base inode 0x%lx as bad.  "
1449			"Run chkdsk.", err, vi->i_ino, ni->type, ni->name_len,
1450			base_vi->i_ino);
1451	make_bad_inode(vi);
1452	if (err != -ENOMEM)
1453		NVolSetErrors(vol);
1454	return err;
1455}
1456
1457/**
1458 * ntfs_read_locked_index_inode - read an index inode from its base inode
1459 * @base_vi:	base inode
1460 * @vi:		index inode to read
1461 *
1462 * ntfs_read_locked_index_inode() is called from ntfs_index_iget() to read the
1463 * index inode described by @vi into memory from the base mft record described
1464 * by @base_ni.
1465 *
1466 * ntfs_read_locked_index_inode() maps, pins and locks the base inode for
1467 * reading and looks up the attributes relating to the index described by @vi
1468 * before setting up the necessary fields in @vi as well as initializing the
1469 * ntfs inode.
1470 *
1471 * Note, index inodes are essentially attribute inodes (NInoAttr() is true)
1472 * with the attribute type set to AT_INDEX_ALLOCATION.  Apart from that, they
1473 * are setup like directory inodes since directories are a special case of
1474 * indices ao they need to be treated in much the same way.  Most importantly,
1475 * for small indices the index allocation attribute might not actually exist.
1476 * However, the index root attribute always exists but this does not need to
1477 * have an inode associated with it and this is why we define a new inode type
1478 * index.  Also, like for directories, we need to have an attribute inode for
1479 * the bitmap attribute corresponding to the index allocation attribute and we
1480 * can store this in the appropriate field of the inode, just like we do for
1481 * normal directory inodes.
1482 *
1483 * Q: What locks are held when the function is called?
1484 * A: i_state has I_NEW set, hence the inode is locked, also
1485 *    i_count is set to 1, so it is not going to go away
1486 *
1487 * Return 0 on success and -errno on error.  In the error case, the inode will
1488 * have had make_bad_inode() executed on it.
1489 */
1490static int ntfs_read_locked_index_inode(struct inode *base_vi, struct inode *vi)
1491{
1492	loff_t bvi_size;
1493	ntfs_volume *vol = NTFS_SB(vi->i_sb);
1494	ntfs_inode *ni, *base_ni, *bni;
1495	struct inode *bvi;
1496	MFT_RECORD *m;
1497	ATTR_RECORD *a;
1498	ntfs_attr_search_ctx *ctx;
1499	INDEX_ROOT *ir;
1500	u8 *ir_end, *index_end;
1501	int err = 0;
1502
1503	ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
1504	ntfs_init_big_inode(vi);
1505	ni	= NTFS_I(vi);
1506	base_ni = NTFS_I(base_vi);
1507	/* Just mirror the values from the base inode. */
1508	vi->i_version	= base_vi->i_version;
1509	vi->i_uid	= base_vi->i_uid;
1510	vi->i_gid	= base_vi->i_gid;
1511	set_nlink(vi, base_vi->i_nlink);
1512	vi->i_mtime	= base_vi->i_mtime;
1513	vi->i_ctime	= base_vi->i_ctime;
1514	vi->i_atime	= base_vi->i_atime;
1515	vi->i_generation = ni->seq_no = base_ni->seq_no;
1516	/* Set inode type to zero but preserve permissions. */
1517	vi->i_mode	= base_vi->i_mode & ~S_IFMT;
1518	/* Map the mft record for the base inode. */
1519	m = map_mft_record(base_ni);
1520	if (IS_ERR(m)) {
1521		err = PTR_ERR(m);
1522		goto err_out;
1523	}
1524	ctx = ntfs_attr_get_search_ctx(base_ni, m);
1525	if (!ctx) {
1526		err = -ENOMEM;
1527		goto unm_err_out;
1528	}
1529	/* Find the index root attribute. */
1530	err = ntfs_attr_lookup(AT_INDEX_ROOT, ni->name, ni->name_len,
1531			CASE_SENSITIVE, 0, NULL, 0, ctx);
1532	if (unlikely(err)) {
1533		if (err == -ENOENT)
1534			ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
1535					"missing.");
1536		goto unm_err_out;
1537	}
1538	a = ctx->attr;
1539	/* Set up the state. */
1540	if (unlikely(a->non_resident)) {
1541		ntfs_error(vol->sb, "$INDEX_ROOT attribute is not resident.");
1542		goto unm_err_out;
1543	}
1544	/* Ensure the attribute name is placed before the value. */
1545	if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1546			le16_to_cpu(a->data.resident.value_offset)))) {
1547		ntfs_error(vol->sb, "$INDEX_ROOT attribute name is placed "
1548				"after the attribute value.");
1549		goto unm_err_out;
1550	}
1551	/*
1552	 * Compressed/encrypted/sparse index root is not allowed, except for
1553	 * directories of course but those are not dealt with here.
1554	 */
1555	if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_ENCRYPTED |
1556			ATTR_IS_SPARSE)) {
1557		ntfs_error(vi->i_sb, "Found compressed/encrypted/sparse index "
1558				"root attribute.");
1559		goto unm_err_out;
1560	}
1561	ir = (INDEX_ROOT*)((u8*)a + le16_to_cpu(a->data.resident.value_offset));
1562	ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
1563	if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
1564		ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is corrupt.");
1565		goto unm_err_out;
1566	}
1567	index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length);
1568	if (index_end > ir_end) {
1569		ntfs_error(vi->i_sb, "Index is corrupt.");
1570		goto unm_err_out;
1571	}
1572	if (ir->type) {
1573		ntfs_error(vi->i_sb, "Index type is not 0 (type is 0x%x).",
1574				le32_to_cpu(ir->type));
1575		goto unm_err_out;
1576	}
1577	ni->itype.index.collation_rule = ir->collation_rule;
1578	ntfs_debug("Index collation rule is 0x%x.",
1579			le32_to_cpu(ir->collation_rule));
1580	ni->itype.index.block_size = le32_to_cpu(ir->index_block_size);
1581	if (!is_power_of_2(ni->itype.index.block_size)) {
1582		ntfs_error(vi->i_sb, "Index block size (%u) is not a power of "
1583				"two.", ni->itype.index.block_size);
1584		goto unm_err_out;
1585	}
1586	if (ni->itype.index.block_size > PAGE_CACHE_SIZE) {
1587		ntfs_error(vi->i_sb, "Index block size (%u) > PAGE_CACHE_SIZE "
1588				"(%ld) is not supported.  Sorry.",
1589				ni->itype.index.block_size, PAGE_CACHE_SIZE);
1590		err = -EOPNOTSUPP;
1591		goto unm_err_out;
1592	}
1593	if (ni->itype.index.block_size < NTFS_BLOCK_SIZE) {
1594		ntfs_error(vi->i_sb, "Index block size (%u) < NTFS_BLOCK_SIZE "
1595				"(%i) is not supported.  Sorry.",
1596				ni->itype.index.block_size, NTFS_BLOCK_SIZE);
1597		err = -EOPNOTSUPP;
1598		goto unm_err_out;
1599	}
1600	ni->itype.index.block_size_bits = ffs(ni->itype.index.block_size) - 1;
1601	/* Determine the size of a vcn in the index. */
1602	if (vol->cluster_size <= ni->itype.index.block_size) {
1603		ni->itype.index.vcn_size = vol->cluster_size;
1604		ni->itype.index.vcn_size_bits = vol->cluster_size_bits;
1605	} else {
1606		ni->itype.index.vcn_size = vol->sector_size;
1607		ni->itype.index.vcn_size_bits = vol->sector_size_bits;
1608	}
1609	/* Check for presence of index allocation attribute. */
1610	if (!(ir->index.flags & LARGE_INDEX)) {
1611		/* No index allocation. */
1612		vi->i_size = ni->initialized_size = ni->allocated_size = 0;
1613		/* We are done with the mft record, so we release it. */
1614		ntfs_attr_put_search_ctx(ctx);
1615		unmap_mft_record(base_ni);
1616		m = NULL;
1617		ctx = NULL;
1618		goto skip_large_index_stuff;
1619	} /* LARGE_INDEX:  Index allocation present.  Setup state. */
1620	NInoSetIndexAllocPresent(ni);
1621	/* Find index allocation attribute. */
1622	ntfs_attr_reinit_search_ctx(ctx);
1623	err = ntfs_attr_lookup(AT_INDEX_ALLOCATION, ni->name, ni->name_len,
1624			CASE_SENSITIVE, 0, NULL, 0, ctx);
1625	if (unlikely(err)) {
1626		if (err == -ENOENT)
1627			ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1628					"not present but $INDEX_ROOT "
1629					"indicated it is.");
1630		else
1631			ntfs_error(vi->i_sb, "Failed to lookup "
1632					"$INDEX_ALLOCATION attribute.");
1633		goto unm_err_out;
1634	}
1635	a = ctx->attr;
1636	if (!a->non_resident) {
1637		ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1638				"resident.");
1639		goto unm_err_out;
1640	}
1641	/*
1642	 * Ensure the attribute name is placed before the mapping pairs array.
1643	 */
1644	if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1645			le16_to_cpu(
1646			a->data.non_resident.mapping_pairs_offset)))) {
1647		ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name is "
1648				"placed after the mapping pairs array.");
1649		goto unm_err_out;
1650	}
1651	if (a->flags & ATTR_IS_ENCRYPTED) {
1652		ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1653				"encrypted.");
1654		goto unm_err_out;
1655	}
1656	if (a->flags & ATTR_IS_SPARSE) {
1657		ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is sparse.");
1658		goto unm_err_out;
1659	}
1660	if (a->flags & ATTR_COMPRESSION_MASK) {
1661		ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1662				"compressed.");
1663		goto unm_err_out;
1664	}
1665	if (a->data.non_resident.lowest_vcn) {
1666		ntfs_error(vi->i_sb, "First extent of $INDEX_ALLOCATION "
1667				"attribute has non zero lowest_vcn.");
1668		goto unm_err_out;
1669	}
1670	vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
1671	ni->initialized_size = sle64_to_cpu(
1672			a->data.non_resident.initialized_size);
1673	ni->allocated_size = sle64_to_cpu(a->data.non_resident.allocated_size);
1674	/*
1675	 * We are done with the mft record, so we release it.  Otherwise
1676	 * we would deadlock in ntfs_attr_iget().
1677	 */
1678	ntfs_attr_put_search_ctx(ctx);
1679	unmap_mft_record(base_ni);
1680	m = NULL;
1681	ctx = NULL;
1682	/* Get the index bitmap attribute inode. */
1683	bvi = ntfs_attr_iget(base_vi, AT_BITMAP, ni->name, ni->name_len);
1684	if (IS_ERR(bvi)) {
1685		ntfs_error(vi->i_sb, "Failed to get bitmap attribute.");
1686		err = PTR_ERR(bvi);
1687		goto unm_err_out;
1688	}
1689	bni = NTFS_I(bvi);
1690	if (NInoCompressed(bni) || NInoEncrypted(bni) ||
1691			NInoSparse(bni)) {
1692		ntfs_error(vi->i_sb, "$BITMAP attribute is compressed and/or "
1693				"encrypted and/or sparse.");
1694		goto iput_unm_err_out;
1695	}
1696	/* Consistency check bitmap size vs. index allocation size. */
1697	bvi_size = i_size_read(bvi);
1698	if ((bvi_size << 3) < (vi->i_size >> ni->itype.index.block_size_bits)) {
1699		ntfs_error(vi->i_sb, "Index bitmap too small (0x%llx) for "
1700				"index allocation (0x%llx).", bvi_size << 3,
1701				vi->i_size);
1702		goto iput_unm_err_out;
1703	}
1704	iput(bvi);
1705skip_large_index_stuff:
1706	/* Setup the operations for this index inode. */
1707	vi->i_mapping->a_ops = &ntfs_mst_aops;
1708	vi->i_blocks = ni->allocated_size >> 9;
1709	/*
1710	 * Make sure the base inode doesn't go away and attach it to the
1711	 * index inode.
1712	 */
1713	igrab(base_vi);
1714	ni->ext.base_ntfs_ino = base_ni;
1715	ni->nr_extents = -1;
1716
1717	ntfs_debug("Done.");
1718	return 0;
1719iput_unm_err_out:
1720	iput(bvi);
1721unm_err_out:
1722	if (!err)
1723		err = -EIO;
1724	if (ctx)
1725		ntfs_attr_put_search_ctx(ctx);
1726	if (m)
1727		unmap_mft_record(base_ni);
1728err_out:
1729	ntfs_error(vi->i_sb, "Failed with error code %i while reading index "
1730			"inode (mft_no 0x%lx, name_len %i.", err, vi->i_ino,
1731			ni->name_len);
1732	make_bad_inode(vi);
1733	if (err != -EOPNOTSUPP && err != -ENOMEM)
1734		NVolSetErrors(vol);
1735	return err;
1736}
1737
1738/*
1739 * The MFT inode has special locking, so teach the lock validator
1740 * about this by splitting off the locking rules of the MFT from
1741 * the locking rules of other inodes. The MFT inode can never be
1742 * accessed from the VFS side (or even internally), only by the
1743 * map_mft functions.
1744 */
1745static struct lock_class_key mft_ni_runlist_lock_key, mft_ni_mrec_lock_key;
1746
1747/**
1748 * ntfs_read_inode_mount - special read_inode for mount time use only
1749 * @vi:		inode to read
1750 *
1751 * Read inode FILE_MFT at mount time, only called with super_block lock
1752 * held from within the read_super() code path.
1753 *
1754 * This function exists because when it is called the page cache for $MFT/$DATA
1755 * is not initialized and hence we cannot get at the contents of mft records
1756 * by calling map_mft_record*().
1757 *
1758 * Further it needs to cope with the circular references problem, i.e. cannot
1759 * load any attributes other than $ATTRIBUTE_LIST until $DATA is loaded, because
1760 * we do not know where the other extent mft records are yet and again, because
1761 * we cannot call map_mft_record*() yet.  Obviously this applies only when an
1762 * attribute list is actually present in $MFT inode.
1763 *
1764 * We solve these problems by starting with the $DATA attribute before anything
1765 * else and iterating using ntfs_attr_lookup($DATA) over all extents.  As each
1766 * extent is found, we ntfs_mapping_pairs_decompress() including the implied
1767 * ntfs_runlists_merge().  Each step of the iteration necessarily provides
1768 * sufficient information for the next step to complete.
1769 *
1770 * This should work but there are two possible pit falls (see inline comments
1771 * below), but only time will tell if they are real pits or just smoke...
1772 */
1773int ntfs_read_inode_mount(struct inode *vi)
1774{
1775	VCN next_vcn, last_vcn, highest_vcn;
1776	s64 block;
1777	struct super_block *sb = vi->i_sb;
1778	ntfs_volume *vol = NTFS_SB(sb);
1779	struct buffer_head *bh;
1780	ntfs_inode *ni;
1781	MFT_RECORD *m = NULL;
1782	ATTR_RECORD *a;
1783	ntfs_attr_search_ctx *ctx;
1784	unsigned int i, nr_blocks;
1785	int err;
1786
1787	ntfs_debug("Entering.");
1788
1789	/* Initialize the ntfs specific part of @vi. */
1790	ntfs_init_big_inode(vi);
1791
1792	ni = NTFS_I(vi);
1793
1794	/* Setup the data attribute. It is special as it is mst protected. */
1795	NInoSetNonResident(ni);
1796	NInoSetMstProtected(ni);
1797	NInoSetSparseDisabled(ni);
1798	ni->type = AT_DATA;
1799	ni->name = NULL;
1800	ni->name_len = 0;
1801	/*
1802	 * This sets up our little cheat allowing us to reuse the async read io
1803	 * completion handler for directories.
1804	 */
1805	ni->itype.index.block_size = vol->mft_record_size;
1806	ni->itype.index.block_size_bits = vol->mft_record_size_bits;
1807
1808	/* Very important! Needed to be able to call map_mft_record*(). */
1809	vol->mft_ino = vi;
1810
1811	/* Allocate enough memory to read the first mft record. */
1812	if (vol->mft_record_size > 64 * 1024) {
1813		ntfs_error(sb, "Unsupported mft record size %i (max 64kiB).",
1814				vol->mft_record_size);
1815		goto err_out;
1816	}
1817	i = vol->mft_record_size;
1818	if (i < sb->s_blocksize)
1819		i = sb->s_blocksize;
1820	m = (MFT_RECORD*)ntfs_malloc_nofs(i);
1821	if (!m) {
1822		ntfs_error(sb, "Failed to allocate buffer for $MFT record 0.");
1823		goto err_out;
1824	}
1825
1826	/* Determine the first block of the $MFT/$DATA attribute. */
1827	block = vol->mft_lcn << vol->cluster_size_bits >>
1828			sb->s_blocksize_bits;
1829	nr_blocks = vol->mft_record_size >> sb->s_blocksize_bits;
1830	if (!nr_blocks)
1831		nr_blocks = 1;
1832
1833	/* Load $MFT/$DATA's first mft record. */
1834	for (i = 0; i < nr_blocks; i++) {
1835		bh = sb_bread(sb, block++);
1836		if (!bh) {
1837			ntfs_error(sb, "Device read failed.");
1838			goto err_out;
1839		}
1840		memcpy((char*)m + (i << sb->s_blocksize_bits), bh->b_data,
1841				sb->s_blocksize);
1842		brelse(bh);
1843	}
1844
1845	/* Apply the mst fixups. */
1846	if (post_read_mst_fixup((NTFS_RECORD*)m, vol->mft_record_size)) {
1847		/* FIXME: Try to use the $MFTMirr now. */
1848		ntfs_error(sb, "MST fixup failed. $MFT is corrupt.");
1849		goto err_out;
1850	}
1851
1852	/* Need this to sanity check attribute list references to $MFT. */
1853	vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);
1854
1855	/* Provides readpage() and sync_page() for map_mft_record(). */
1856	vi->i_mapping->a_ops = &ntfs_mst_aops;
1857
1858	ctx = ntfs_attr_get_search_ctx(ni, m);
1859	if (!ctx) {
1860		err = -ENOMEM;
1861		goto err_out;
1862	}
1863
1864	/* Find the attribute list attribute if present. */
1865	err = ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, 0, 0, NULL, 0, ctx);
1866	if (err) {
1867		if (unlikely(err != -ENOENT)) {
1868			ntfs_error(sb, "Failed to lookup attribute list "
1869					"attribute. You should run chkdsk.");
1870			goto put_err_out;
1871		}
1872	} else /* if (!err) */ {
1873		ATTR_LIST_ENTRY *al_entry, *next_al_entry;
1874		u8 *al_end;
1875		static const char *es = "  Not allowed.  $MFT is corrupt.  "
1876				"You should run chkdsk.";
1877
1878		ntfs_debug("Attribute list attribute found in $MFT.");
1879		NInoSetAttrList(ni);
1880		a = ctx->attr;
1881		if (a->flags & ATTR_COMPRESSION_MASK) {
1882			ntfs_error(sb, "Attribute list attribute is "
1883					"compressed.%s", es);
1884			goto put_err_out;
1885		}
1886		if (a->flags & ATTR_IS_ENCRYPTED ||
1887				a->flags & ATTR_IS_SPARSE) {
1888			if (a->non_resident) {
1889				ntfs_error(sb, "Non-resident attribute list "
1890						"attribute is encrypted/"
1891						"sparse.%s", es);
1892				goto put_err_out;
1893			}
1894			ntfs_warning(sb, "Resident attribute list attribute "
1895					"in $MFT system file is marked "
1896					"encrypted/sparse which is not true.  "
1897					"However, Windows allows this and "
1898					"chkdsk does not detect or correct it "
1899					"so we will just ignore the invalid "
1900					"flags and pretend they are not set.");
1901		}
1902		/* Now allocate memory for the attribute list. */
1903		ni->attr_list_size = (u32)ntfs_attr_size(a);
1904		ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
1905		if (!ni->attr_list) {
1906			ntfs_error(sb, "Not enough memory to allocate buffer "
1907					"for attribute list.");
1908			goto put_err_out;
1909		}
1910		if (a->non_resident) {
1911			NInoSetAttrListNonResident(ni);
1912			if (a->data.non_resident.lowest_vcn) {
1913				ntfs_error(sb, "Attribute list has non zero "
1914						"lowest_vcn. $MFT is corrupt. "
1915						"You should run chkdsk.");
1916				goto put_err_out;
1917			}
1918			/* Setup the runlist. */
1919			ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
1920					a, NULL);
1921			if (IS_ERR(ni->attr_list_rl.rl)) {
1922				err = PTR_ERR(ni->attr_list_rl.rl);
1923				ni->attr_list_rl.rl = NULL;
1924				ntfs_error(sb, "Mapping pairs decompression "
1925						"failed with error code %i.",
1926						-err);
1927				goto put_err_out;
1928			}
1929			/* Now load the attribute list. */
1930			if ((err = load_attribute_list(vol, &ni->attr_list_rl,
1931					ni->attr_list, ni->attr_list_size,
1932					sle64_to_cpu(a->data.
1933					non_resident.initialized_size)))) {
1934				ntfs_error(sb, "Failed to load attribute list "
1935						"attribute with error code %i.",
1936						-err);
1937				goto put_err_out;
1938			}
1939		} else /* if (!ctx.attr->non_resident) */ {
1940			if ((u8*)a + le16_to_cpu(
1941					a->data.resident.value_offset) +
1942					le32_to_cpu(
1943					a->data.resident.value_length) >
1944					(u8*)ctx->mrec + vol->mft_record_size) {
1945				ntfs_error(sb, "Corrupt attribute list "
1946						"attribute.");
1947				goto put_err_out;
1948			}
1949			/* Now copy the attribute list. */
1950			memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
1951					a->data.resident.value_offset),
1952					le32_to_cpu(
1953					a->data.resident.value_length));
1954		}
1955		/* The attribute list is now setup in memory. */
1956		/*
1957		 * FIXME: I don't know if this case is actually possible.
1958		 * According to logic it is not possible but I have seen too
1959		 * many weird things in MS software to rely on logic... Thus we
1960		 * perform a manual search and make sure the first $MFT/$DATA
1961		 * extent is in the base inode. If it is not we abort with an
1962		 * error and if we ever see a report of this error we will need
1963		 * to do some magic in order to have the necessary mft record
1964		 * loaded and in the right place in the page cache. But
1965		 * hopefully logic will prevail and this never happens...
1966		 */
1967		al_entry = (ATTR_LIST_ENTRY*)ni->attr_list;
1968		al_end = (u8*)al_entry + ni->attr_list_size;
1969		for (;; al_entry = next_al_entry) {
1970			/* Out of bounds check. */
1971			if ((u8*)al_entry < ni->attr_list ||
1972					(u8*)al_entry > al_end)
1973				goto em_put_err_out;
1974			/* Catch the end of the attribute list. */
1975			if ((u8*)al_entry == al_end)
1976				goto em_put_err_out;
1977			if (!al_entry->length)
1978				goto em_put_err_out;
1979			if ((u8*)al_entry + 6 > al_end || (u8*)al_entry +
1980					le16_to_cpu(al_entry->length) > al_end)
1981				goto em_put_err_out;
1982			next_al_entry = (ATTR_LIST_ENTRY*)((u8*)al_entry +
1983					le16_to_cpu(al_entry->length));
1984			if (le32_to_cpu(al_entry->type) > le32_to_cpu(AT_DATA))
1985				goto em_put_err_out;
1986			if (AT_DATA != al_entry->type)
1987				continue;
1988			/* We want an unnamed attribute. */
1989			if (al_entry->name_length)
1990				goto em_put_err_out;
1991			/* Want the first entry, i.e. lowest_vcn == 0. */
1992			if (al_entry->lowest_vcn)
1993				goto em_put_err_out;
1994			/* First entry has to be in the base mft record. */
1995			if (MREF_LE(al_entry->mft_reference) != vi->i_ino) {
1996				/* MFT references do not match, logic fails. */
1997				ntfs_error(sb, "BUG: The first $DATA extent "
1998						"of $MFT is not in the base "
1999						"mft record. Please report "
2000						"you saw this message to "
2001						"linux-ntfs-dev@lists."
2002						"sourceforge.net");
2003				goto put_err_out;
2004			} else {
2005				/* Sequence numbers must match. */
2006				if (MSEQNO_LE(al_entry->mft_reference) !=
2007						ni->seq_no)
2008					goto em_put_err_out;
2009				/* Got it. All is ok. We can stop now. */
2010				break;
2011			}
2012		}
2013	}
2014
2015	ntfs_attr_reinit_search_ctx(ctx);
2016
2017	/* Now load all attribute extents. */
2018	a = NULL;
2019	next_vcn = last_vcn = highest_vcn = 0;
2020	while (!(err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, next_vcn, NULL, 0,
2021			ctx))) {
2022		runlist_element *nrl;
2023
2024		/* Cache the current attribute. */
2025		a = ctx->attr;
2026		/* $MFT must be non-resident. */
2027		if (!a->non_resident) {
2028			ntfs_error(sb, "$MFT must be non-resident but a "
2029					"resident extent was found. $MFT is "
2030					"corrupt. Run chkdsk.");
2031			goto put_err_out;
2032		}
2033		/* $MFT must be uncompressed and unencrypted. */
2034		if (a->flags & ATTR_COMPRESSION_MASK ||
2035				a->flags & ATTR_IS_ENCRYPTED ||
2036				a->flags & ATTR_IS_SPARSE) {
2037			ntfs_error(sb, "$MFT must be uncompressed, "
2038					"non-sparse, and unencrypted but a "
2039					"compressed/sparse/encrypted extent "
2040					"was found. $MFT is corrupt. Run "
2041					"chkdsk.");
2042			goto put_err_out;
2043		}
2044		/*
2045		 * Decompress the mapping pairs array of this extent and merge
2046		 * the result into the existing runlist. No need for locking
2047		 * as we have exclusive access to the inode at this time and we
2048		 * are a mount in progress task, too.
2049		 */
2050		nrl = ntfs_mapping_pairs_decompress(vol, a, ni->runlist.rl);
2051		if (IS_ERR(nrl)) {
2052			ntfs_error(sb, "ntfs_mapping_pairs_decompress() "
2053					"failed with error code %ld.  $MFT is "
2054					"corrupt.", PTR_ERR(nrl));
2055			goto put_err_out;
2056		}
2057		ni->runlist.rl = nrl;
2058
2059		/* Are we in the first extent? */
2060		if (!next_vcn) {
2061			if (a->data.non_resident.lowest_vcn) {
2062				ntfs_error(sb, "First extent of $DATA "
2063						"attribute has non zero "
2064						"lowest_vcn. $MFT is corrupt. "
2065						"You should run chkdsk.");
2066				goto put_err_out;
2067			}
2068			/* Get the last vcn in the $DATA attribute. */
2069			last_vcn = sle64_to_cpu(
2070					a->data.non_resident.allocated_size)
2071					>> vol->cluster_size_bits;
2072			/* Fill in the inode size. */
2073			vi->i_size = sle64_to_cpu(
2074					a->data.non_resident.data_size);
2075			ni->initialized_size = sle64_to_cpu(
2076					a->data.non_resident.initialized_size);
2077			ni->allocated_size = sle64_to_cpu(
2078					a->data.non_resident.allocated_size);
2079			/*
2080			 * Verify the number of mft records does not exceed
2081			 * 2^32 - 1.
2082			 */
2083			if ((vi->i_size >> vol->mft_record_size_bits) >=
2084					(1ULL << 32)) {
2085				ntfs_error(sb, "$MFT is too big! Aborting.");
2086				goto put_err_out;
2087			}
2088			/*
2089			 * We have got the first extent of the runlist for
2090			 * $MFT which means it is now relatively safe to call
2091			 * the normal ntfs_read_inode() function.
2092			 * Complete reading the inode, this will actually
2093			 * re-read the mft record for $MFT, this time entering
2094			 * it into the page cache with which we complete the
2095			 * kick start of the volume. It should be safe to do
2096			 * this now as the first extent of $MFT/$DATA is
2097			 * already known and we would hope that we don't need
2098			 * further extents in order to find the other
2099			 * attributes belonging to $MFT. Only time will tell if
2100			 * this is really the case. If not we will have to play
2101			 * magic at this point, possibly duplicating a lot of
2102			 * ntfs_read_inode() at this point. We will need to
2103			 * ensure we do enough of its work to be able to call
2104			 * ntfs_read_inode() on extents of $MFT/$DATA. But lets
2105			 * hope this never happens...
2106			 */
2107			ntfs_read_locked_inode(vi);
2108			if (is_bad_inode(vi)) {
2109				ntfs_error(sb, "ntfs_read_inode() of $MFT "
2110						"failed. BUG or corrupt $MFT. "
2111						"Run chkdsk and if no errors "
2112						"are found, please report you "
2113						"saw this message to "
2114						"linux-ntfs-dev@lists."
2115						"sourceforge.net");
2116				ntfs_attr_put_search_ctx(ctx);
2117				/* Revert to the safe super operations. */
2118				ntfs_free(m);
2119				return -1;
2120			}
2121			/*
2122			 * Re-initialize some specifics about $MFT's inode as
2123			 * ntfs_read_inode() will have set up the default ones.
2124			 */
2125			/* Set uid and gid to root. */
2126			vi->i_uid = GLOBAL_ROOT_UID;
2127			vi->i_gid = GLOBAL_ROOT_GID;
2128			/* Regular file. No access for anyone. */
2129			vi->i_mode = S_IFREG;
2130			/* No VFS initiated operations allowed for $MFT. */
2131			vi->i_op = &ntfs_empty_inode_ops;
2132			vi->i_fop = &ntfs_empty_file_ops;
2133		}
2134
2135		/* Get the lowest vcn for the next extent. */
2136		highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
2137		next_vcn = highest_vcn + 1;
2138
2139		/* Only one extent or error, which we catch below. */
2140		if (next_vcn <= 0)
2141			break;
2142
2143		/* Avoid endless loops due to corruption. */
2144		if (next_vcn < sle64_to_cpu(
2145				a->data.non_resident.lowest_vcn)) {
2146			ntfs_error(sb, "$MFT has corrupt attribute list "
2147					"attribute. Run chkdsk.");
2148			goto put_err_out;
2149		}
2150	}
2151	if (err != -ENOENT) {
2152		ntfs_error(sb, "Failed to lookup $MFT/$DATA attribute extent. "
2153				"$MFT is corrupt. Run chkdsk.");
2154		goto put_err_out;
2155	}
2156	if (!a) {
2157		ntfs_error(sb, "$MFT/$DATA attribute not found. $MFT is "
2158				"corrupt. Run chkdsk.");
2159		goto put_err_out;
2160	}
2161	if (highest_vcn && highest_vcn != last_vcn - 1) {
2162		ntfs_error(sb, "Failed to load the complete runlist for "
2163				"$MFT/$DATA. Driver bug or corrupt $MFT. "
2164				"Run chkdsk.");
2165		ntfs_debug("highest_vcn = 0x%llx, last_vcn - 1 = 0x%llx",
2166				(unsigned long long)highest_vcn,
2167				(unsigned long long)last_vcn - 1);
2168		goto put_err_out;
2169	}
2170	ntfs_attr_put_search_ctx(ctx);
2171	ntfs_debug("Done.");
2172	ntfs_free(m);
2173
2174	/*
2175	 * Split the locking rules of the MFT inode from the
2176	 * locking rules of other inodes:
2177	 */
2178	lockdep_set_class(&ni->runlist.lock, &mft_ni_runlist_lock_key);
2179	lockdep_set_class(&ni->mrec_lock, &mft_ni_mrec_lock_key);
2180
2181	return 0;
2182
2183em_put_err_out:
2184	ntfs_error(sb, "Couldn't find first extent of $DATA attribute in "
2185			"attribute list. $MFT is corrupt. Run chkdsk.");
2186put_err_out:
2187	ntfs_attr_put_search_ctx(ctx);
2188err_out:
2189	ntfs_error(sb, "Failed. Marking inode as bad.");
2190	make_bad_inode(vi);
2191	ntfs_free(m);
2192	return -1;
2193}
2194
2195static void __ntfs_clear_inode(ntfs_inode *ni)
2196{
2197	/* Free all alocated memory. */
2198	down_write(&ni->runlist.lock);
2199	if (ni->runlist.rl) {
2200		ntfs_free(ni->runlist.rl);
2201		ni->runlist.rl = NULL;
2202	}
2203	up_write(&ni->runlist.lock);
2204
2205	if (ni->attr_list) {
2206		ntfs_free(ni->attr_list);
2207		ni->attr_list = NULL;
2208	}
2209
2210	down_write(&ni->attr_list_rl.lock);
2211	if (ni->attr_list_rl.rl) {
2212		ntfs_free(ni->attr_list_rl.rl);
2213		ni->attr_list_rl.rl = NULL;
2214	}
2215	up_write(&ni->attr_list_rl.lock);
2216
2217	if (ni->name_len && ni->name != I30) {
2218		/* Catch bugs... */
2219		BUG_ON(!ni->name);
2220		kfree(ni->name);
2221	}
2222}
2223
2224void ntfs_clear_extent_inode(ntfs_inode *ni)
2225{
2226	ntfs_debug("Entering for inode 0x%lx.", ni->mft_no);
2227
2228	BUG_ON(NInoAttr(ni));
2229	BUG_ON(ni->nr_extents != -1);
2230
2231#ifdef NTFS_RW
2232	if (NInoDirty(ni)) {
2233		if (!is_bad_inode(VFS_I(ni->ext.base_ntfs_ino)))
2234			ntfs_error(ni->vol->sb, "Clearing dirty extent inode!  "
2235					"Losing data!  This is a BUG!!!");
2236		// FIXME:  Do something!!!
2237	}
2238#endif /* NTFS_RW */
2239
2240	__ntfs_clear_inode(ni);
2241
2242	/* Bye, bye... */
2243	ntfs_destroy_extent_inode(ni);
2244}
2245
2246/**
2247 * ntfs_evict_big_inode - clean up the ntfs specific part of an inode
2248 * @vi:		vfs inode pending annihilation
2249 *
2250 * When the VFS is going to remove an inode from memory, ntfs_clear_big_inode()
2251 * is called, which deallocates all memory belonging to the NTFS specific part
2252 * of the inode and returns.
2253 *
2254 * If the MFT record is dirty, we commit it before doing anything else.
2255 */
2256void ntfs_evict_big_inode(struct inode *vi)
2257{
2258	ntfs_inode *ni = NTFS_I(vi);
2259
2260	truncate_inode_pages_final(&vi->i_data);
2261	clear_inode(vi);
2262
2263#ifdef NTFS_RW
2264	if (NInoDirty(ni)) {
2265		bool was_bad = (is_bad_inode(vi));
2266
2267		/* Committing the inode also commits all extent inodes. */
2268		ntfs_commit_inode(vi);
2269
2270		if (!was_bad && (is_bad_inode(vi) || NInoDirty(ni))) {
2271			ntfs_error(vi->i_sb, "Failed to commit dirty inode "
2272					"0x%lx.  Losing data!", vi->i_ino);
2273			// FIXME:  Do something!!!
2274		}
2275	}
2276#endif /* NTFS_RW */
2277
2278	/* No need to lock at this stage as no one else has a reference. */
2279	if (ni->nr_extents > 0) {
2280		int i;
2281
2282		for (i = 0; i < ni->nr_extents; i++)
2283			ntfs_clear_extent_inode(ni->ext.extent_ntfs_inos[i]);
2284		kfree(ni->ext.extent_ntfs_inos);
2285	}
2286
2287	__ntfs_clear_inode(ni);
2288
2289	if (NInoAttr(ni)) {
2290		/* Release the base inode if we are holding it. */
2291		if (ni->nr_extents == -1) {
2292			iput(VFS_I(ni->ext.base_ntfs_ino));
2293			ni->nr_extents = 0;
2294			ni->ext.base_ntfs_ino = NULL;
2295		}
2296	}
 
 
 
2297	return;
2298}
2299
2300/**
2301 * ntfs_show_options - show mount options in /proc/mounts
2302 * @sf:		seq_file in which to write our mount options
2303 * @root:	root of the mounted tree whose mount options to display
2304 *
2305 * Called by the VFS once for each mounted ntfs volume when someone reads
2306 * /proc/mounts in order to display the NTFS specific mount options of each
2307 * mount. The mount options of fs specified by @root are written to the seq file
2308 * @sf and success is returned.
2309 */
2310int ntfs_show_options(struct seq_file *sf, struct dentry *root)
2311{
2312	ntfs_volume *vol = NTFS_SB(root->d_sb);
2313	int i;
2314
2315	seq_printf(sf, ",uid=%i", from_kuid_munged(&init_user_ns, vol->uid));
2316	seq_printf(sf, ",gid=%i", from_kgid_munged(&init_user_ns, vol->gid));
2317	if (vol->fmask == vol->dmask)
2318		seq_printf(sf, ",umask=0%o", vol->fmask);
2319	else {
2320		seq_printf(sf, ",fmask=0%o", vol->fmask);
2321		seq_printf(sf, ",dmask=0%o", vol->dmask);
2322	}
2323	seq_printf(sf, ",nls=%s", vol->nls_map->charset);
2324	if (NVolCaseSensitive(vol))
2325		seq_printf(sf, ",case_sensitive");
2326	if (NVolShowSystemFiles(vol))
2327		seq_printf(sf, ",show_sys_files");
2328	if (!NVolSparseEnabled(vol))
2329		seq_printf(sf, ",disable_sparse");
2330	for (i = 0; on_errors_arr[i].val; i++) {
2331		if (on_errors_arr[i].val & vol->on_errors)
2332			seq_printf(sf, ",errors=%s", on_errors_arr[i].str);
2333	}
2334	seq_printf(sf, ",mft_zone_multiplier=%i", vol->mft_zone_multiplier);
2335	return 0;
2336}
2337
2338#ifdef NTFS_RW
2339
2340static const char *es = "  Leaving inconsistent metadata.  Unmount and run "
2341		"chkdsk.";
2342
2343/**
2344 * ntfs_truncate - called when the i_size of an ntfs inode is changed
2345 * @vi:		inode for which the i_size was changed
2346 *
2347 * We only support i_size changes for normal files at present, i.e. not
2348 * compressed and not encrypted.  This is enforced in ntfs_setattr(), see
2349 * below.
2350 *
2351 * The kernel guarantees that @vi is a regular file (S_ISREG() is true) and
2352 * that the change is allowed.
2353 *
2354 * This implies for us that @vi is a file inode rather than a directory, index,
2355 * or attribute inode as well as that @vi is a base inode.
2356 *
2357 * Returns 0 on success or -errno on error.
2358 *
2359 * Called with ->i_mutex held.
2360 */
2361int ntfs_truncate(struct inode *vi)
2362{
2363	s64 new_size, old_size, nr_freed, new_alloc_size, old_alloc_size;
2364	VCN highest_vcn;
2365	unsigned long flags;
2366	ntfs_inode *base_ni, *ni = NTFS_I(vi);
2367	ntfs_volume *vol = ni->vol;
2368	ntfs_attr_search_ctx *ctx;
2369	MFT_RECORD *m;
2370	ATTR_RECORD *a;
2371	const char *te = "  Leaving file length out of sync with i_size.";
2372	int err, mp_size, size_change, alloc_change;
2373	u32 attr_len;
2374
2375	ntfs_debug("Entering for inode 0x%lx.", vi->i_ino);
2376	BUG_ON(NInoAttr(ni));
2377	BUG_ON(S_ISDIR(vi->i_mode));
2378	BUG_ON(NInoMstProtected(ni));
2379	BUG_ON(ni->nr_extents < 0);
2380retry_truncate:
2381	/*
2382	 * Lock the runlist for writing and map the mft record to ensure it is
2383	 * safe to mess with the attribute runlist and sizes.
2384	 */
2385	down_write(&ni->runlist.lock);
2386	if (!NInoAttr(ni))
2387		base_ni = ni;
2388	else
2389		base_ni = ni->ext.base_ntfs_ino;
2390	m = map_mft_record(base_ni);
2391	if (IS_ERR(m)) {
2392		err = PTR_ERR(m);
2393		ntfs_error(vi->i_sb, "Failed to map mft record for inode 0x%lx "
2394				"(error code %d).%s", vi->i_ino, err, te);
2395		ctx = NULL;
2396		m = NULL;
2397		goto old_bad_out;
2398	}
2399	ctx = ntfs_attr_get_search_ctx(base_ni, m);
2400	if (unlikely(!ctx)) {
2401		ntfs_error(vi->i_sb, "Failed to allocate a search context for "
2402				"inode 0x%lx (not enough memory).%s",
2403				vi->i_ino, te);
2404		err = -ENOMEM;
2405		goto old_bad_out;
2406	}
2407	err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
2408			CASE_SENSITIVE, 0, NULL, 0, ctx);
2409	if (unlikely(err)) {
2410		if (err == -ENOENT) {
2411			ntfs_error(vi->i_sb, "Open attribute is missing from "
2412					"mft record.  Inode 0x%lx is corrupt.  "
2413					"Run chkdsk.%s", vi->i_ino, te);
2414			err = -EIO;
2415		} else
2416			ntfs_error(vi->i_sb, "Failed to lookup attribute in "
2417					"inode 0x%lx (error code %d).%s",
2418					vi->i_ino, err, te);
2419		goto old_bad_out;
2420	}
2421	m = ctx->mrec;
2422	a = ctx->attr;
2423	/*
2424	 * The i_size of the vfs inode is the new size for the attribute value.
2425	 */
2426	new_size = i_size_read(vi);
2427	/* The current size of the attribute value is the old size. */
2428	old_size = ntfs_attr_size(a);
2429	/* Calculate the new allocated size. */
2430	if (NInoNonResident(ni))
2431		new_alloc_size = (new_size + vol->cluster_size - 1) &
2432				~(s64)vol->cluster_size_mask;
2433	else
2434		new_alloc_size = (new_size + 7) & ~7;
2435	/* The current allocated size is the old allocated size. */
2436	read_lock_irqsave(&ni->size_lock, flags);
2437	old_alloc_size = ni->allocated_size;
2438	read_unlock_irqrestore(&ni->size_lock, flags);
2439	/*
2440	 * The change in the file size.  This will be 0 if no change, >0 if the
2441	 * size is growing, and <0 if the size is shrinking.
2442	 */
2443	size_change = -1;
2444	if (new_size - old_size >= 0) {
2445		size_change = 1;
2446		if (new_size == old_size)
2447			size_change = 0;
2448	}
2449	/* As above for the allocated size. */
2450	alloc_change = -1;
2451	if (new_alloc_size - old_alloc_size >= 0) {
2452		alloc_change = 1;
2453		if (new_alloc_size == old_alloc_size)
2454			alloc_change = 0;
2455	}
2456	/*
2457	 * If neither the size nor the allocation are being changed there is
2458	 * nothing to do.
2459	 */
2460	if (!size_change && !alloc_change)
2461		goto unm_done;
2462	/* If the size is changing, check if new size is allowed in $AttrDef. */
2463	if (size_change) {
2464		err = ntfs_attr_size_bounds_check(vol, ni->type, new_size);
2465		if (unlikely(err)) {
2466			if (err == -ERANGE) {
2467				ntfs_error(vol->sb, "Truncate would cause the "
2468						"inode 0x%lx to %simum size "
2469						"for its attribute type "
2470						"(0x%x).  Aborting truncate.",
2471						vi->i_ino,
2472						new_size > old_size ? "exceed "
2473						"the max" : "go under the min",
2474						le32_to_cpu(ni->type));
2475				err = -EFBIG;
2476			} else {
2477				ntfs_error(vol->sb, "Inode 0x%lx has unknown "
2478						"attribute type 0x%x.  "
2479						"Aborting truncate.",
2480						vi->i_ino,
2481						le32_to_cpu(ni->type));
2482				err = -EIO;
2483			}
2484			/* Reset the vfs inode size to the old size. */
2485			i_size_write(vi, old_size);
2486			goto err_out;
2487		}
2488	}
2489	if (NInoCompressed(ni) || NInoEncrypted(ni)) {
2490		ntfs_warning(vi->i_sb, "Changes in inode size are not "
2491				"supported yet for %s files, ignoring.",
2492				NInoCompressed(ni) ? "compressed" :
2493				"encrypted");
2494		err = -EOPNOTSUPP;
2495		goto bad_out;
2496	}
2497	if (a->non_resident)
2498		goto do_non_resident_truncate;
2499	BUG_ON(NInoNonResident(ni));
2500	/* Resize the attribute record to best fit the new attribute size. */
2501	if (new_size < vol->mft_record_size &&
2502			!ntfs_resident_attr_value_resize(m, a, new_size)) {
2503		/* The resize succeeded! */
2504		flush_dcache_mft_record_page(ctx->ntfs_ino);
2505		mark_mft_record_dirty(ctx->ntfs_ino);
2506		write_lock_irqsave(&ni->size_lock, flags);
2507		/* Update the sizes in the ntfs inode and all is done. */
2508		ni->allocated_size = le32_to_cpu(a->length) -
2509				le16_to_cpu(a->data.resident.value_offset);
2510		/*
2511		 * Note ntfs_resident_attr_value_resize() has already done any
2512		 * necessary data clearing in the attribute record.  When the
2513		 * file is being shrunk vmtruncate() will already have cleared
2514		 * the top part of the last partial page, i.e. since this is
2515		 * the resident case this is the page with index 0.  However,
2516		 * when the file is being expanded, the page cache page data
2517		 * between the old data_size, i.e. old_size, and the new_size
2518		 * has not been zeroed.  Fortunately, we do not need to zero it
2519		 * either since on one hand it will either already be zero due
2520		 * to both readpage and writepage clearing partial page data
2521		 * beyond i_size in which case there is nothing to do or in the
2522		 * case of the file being mmap()ped at the same time, POSIX
2523		 * specifies that the behaviour is unspecified thus we do not
2524		 * have to do anything.  This means that in our implementation
2525		 * in the rare case that the file is mmap()ped and a write
2526		 * occurred into the mmap()ped region just beyond the file size
2527		 * and writepage has not yet been called to write out the page
2528		 * (which would clear the area beyond the file size) and we now
2529		 * extend the file size to incorporate this dirty region
2530		 * outside the file size, a write of the page would result in
2531		 * this data being written to disk instead of being cleared.
2532		 * Given both POSIX and the Linux mmap(2) man page specify that
2533		 * this corner case is undefined, we choose to leave it like
2534		 * that as this is much simpler for us as we cannot lock the
2535		 * relevant page now since we are holding too many ntfs locks
2536		 * which would result in a lock reversal deadlock.
2537		 */
2538		ni->initialized_size = new_size;
2539		write_unlock_irqrestore(&ni->size_lock, flags);
2540		goto unm_done;
2541	}
2542	/* If the above resize failed, this must be an attribute extension. */
2543	BUG_ON(size_change < 0);
2544	/*
2545	 * We have to drop all the locks so we can call
2546	 * ntfs_attr_make_non_resident().  This could be optimised by try-
2547	 * locking the first page cache page and only if that fails dropping
2548	 * the locks, locking the page, and redoing all the locking and
2549	 * lookups.  While this would be a huge optimisation, it is not worth
2550	 * it as this is definitely a slow code path as it only ever can happen
2551	 * once for any given file.
2552	 */
2553	ntfs_attr_put_search_ctx(ctx);
2554	unmap_mft_record(base_ni);
2555	up_write(&ni->runlist.lock);
2556	/*
2557	 * Not enough space in the mft record, try to make the attribute
2558	 * non-resident and if successful restart the truncation process.
2559	 */
2560	err = ntfs_attr_make_non_resident(ni, old_size);
2561	if (likely(!err))
2562		goto retry_truncate;
2563	/*
2564	 * Could not make non-resident.  If this is due to this not being
2565	 * permitted for this attribute type or there not being enough space,
2566	 * try to make other attributes non-resident.  Otherwise fail.
2567	 */
2568	if (unlikely(err != -EPERM && err != -ENOSPC)) {
2569		ntfs_error(vol->sb, "Cannot truncate inode 0x%lx, attribute "
2570				"type 0x%x, because the conversion from "
2571				"resident to non-resident attribute failed "
2572				"with error code %i.", vi->i_ino,
2573				(unsigned)le32_to_cpu(ni->type), err);
2574		if (err != -ENOMEM)
2575			err = -EIO;
2576		goto conv_err_out;
2577	}
2578	/* TODO: Not implemented from here, abort. */
2579	if (err == -ENOSPC)
2580		ntfs_error(vol->sb, "Not enough space in the mft record/on "
2581				"disk for the non-resident attribute value.  "
2582				"This case is not implemented yet.");
2583	else /* if (err == -EPERM) */
2584		ntfs_error(vol->sb, "This attribute type may not be "
2585				"non-resident.  This case is not implemented "
2586				"yet.");
2587	err = -EOPNOTSUPP;
2588	goto conv_err_out;
2589#if 0
2590	// TODO: Attempt to make other attributes non-resident.
2591	if (!err)
2592		goto do_resident_extend;
2593	/*
2594	 * Both the attribute list attribute and the standard information
2595	 * attribute must remain in the base inode.  Thus, if this is one of
2596	 * these attributes, we have to try to move other attributes out into
2597	 * extent mft records instead.
2598	 */
2599	if (ni->type == AT_ATTRIBUTE_LIST ||
2600			ni->type == AT_STANDARD_INFORMATION) {
2601		// TODO: Attempt to move other attributes into extent mft
2602		// records.
2603		err = -EOPNOTSUPP;
2604		if (!err)
2605			goto do_resident_extend;
2606		goto err_out;
2607	}
2608	// TODO: Attempt to move this attribute to an extent mft record, but
2609	// only if it is not already the only attribute in an mft record in
2610	// which case there would be nothing to gain.
2611	err = -EOPNOTSUPP;
2612	if (!err)
2613		goto do_resident_extend;
2614	/* There is nothing we can do to make enough space. )-: */
2615	goto err_out;
2616#endif
2617do_non_resident_truncate:
2618	BUG_ON(!NInoNonResident(ni));
2619	if (alloc_change < 0) {
2620		highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
2621		if (highest_vcn > 0 &&
2622				old_alloc_size >> vol->cluster_size_bits >
2623				highest_vcn + 1) {
2624			/*
2625			 * This attribute has multiple extents.  Not yet
2626			 * supported.
2627			 */
2628			ntfs_error(vol->sb, "Cannot truncate inode 0x%lx, "
2629					"attribute type 0x%x, because the "
2630					"attribute is highly fragmented (it "
2631					"consists of multiple extents) and "
2632					"this case is not implemented yet.",
2633					vi->i_ino,
2634					(unsigned)le32_to_cpu(ni->type));
2635			err = -EOPNOTSUPP;
2636			goto bad_out;
2637		}
2638	}
2639	/*
2640	 * If the size is shrinking, need to reduce the initialized_size and
2641	 * the data_size before reducing the allocation.
2642	 */
2643	if (size_change < 0) {
2644		/*
2645		 * Make the valid size smaller (i_size is already up-to-date).
2646		 */
2647		write_lock_irqsave(&ni->size_lock, flags);
2648		if (new_size < ni->initialized_size) {
2649			ni->initialized_size = new_size;
2650			a->data.non_resident.initialized_size =
2651					cpu_to_sle64(new_size);
2652		}
2653		a->data.non_resident.data_size = cpu_to_sle64(new_size);
2654		write_unlock_irqrestore(&ni->size_lock, flags);
2655		flush_dcache_mft_record_page(ctx->ntfs_ino);
2656		mark_mft_record_dirty(ctx->ntfs_ino);
2657		/* If the allocated size is not changing, we are done. */
2658		if (!alloc_change)
2659			goto unm_done;
2660		/*
2661		 * If the size is shrinking it makes no sense for the
2662		 * allocation to be growing.
2663		 */
2664		BUG_ON(alloc_change > 0);
2665	} else /* if (size_change >= 0) */ {
2666		/*
2667		 * The file size is growing or staying the same but the
2668		 * allocation can be shrinking, growing or staying the same.
2669		 */
2670		if (alloc_change > 0) {
2671			/*
2672			 * We need to extend the allocation and possibly update
2673			 * the data size.  If we are updating the data size,
2674			 * since we are not touching the initialized_size we do
2675			 * not need to worry about the actual data on disk.
2676			 * And as far as the page cache is concerned, there
2677			 * will be no pages beyond the old data size and any
2678			 * partial region in the last page between the old and
2679			 * new data size (or the end of the page if the new
2680			 * data size is outside the page) does not need to be
2681			 * modified as explained above for the resident
2682			 * attribute truncate case.  To do this, we simply drop
2683			 * the locks we hold and leave all the work to our
2684			 * friendly helper ntfs_attr_extend_allocation().
2685			 */
2686			ntfs_attr_put_search_ctx(ctx);
2687			unmap_mft_record(base_ni);
2688			up_write(&ni->runlist.lock);
2689			err = ntfs_attr_extend_allocation(ni, new_size,
2690					size_change > 0 ? new_size : -1, -1);
2691			/*
2692			 * ntfs_attr_extend_allocation() will have done error
2693			 * output already.
2694			 */
2695			goto done;
2696		}
2697		if (!alloc_change)
2698			goto alloc_done;
2699	}
2700	/* alloc_change < 0 */
2701	/* Free the clusters. */
2702	nr_freed = ntfs_cluster_free(ni, new_alloc_size >>
2703			vol->cluster_size_bits, -1, ctx);
2704	m = ctx->mrec;
2705	a = ctx->attr;
2706	if (unlikely(nr_freed < 0)) {
2707		ntfs_error(vol->sb, "Failed to release cluster(s) (error code "
2708				"%lli).  Unmount and run chkdsk to recover "
2709				"the lost cluster(s).", (long long)nr_freed);
2710		NVolSetErrors(vol);
2711		nr_freed = 0;
2712	}
2713	/* Truncate the runlist. */
2714	err = ntfs_rl_truncate_nolock(vol, &ni->runlist,
2715			new_alloc_size >> vol->cluster_size_bits);
2716	/*
2717	 * If the runlist truncation failed and/or the search context is no
2718	 * longer valid, we cannot resize the attribute record or build the
2719	 * mapping pairs array thus we mark the inode bad so that no access to
2720	 * the freed clusters can happen.
2721	 */
2722	if (unlikely(err || IS_ERR(m))) {
2723		ntfs_error(vol->sb, "Failed to %s (error code %li).%s",
2724				IS_ERR(m) ?
2725				"restore attribute search context" :
2726				"truncate attribute runlist",
2727				IS_ERR(m) ? PTR_ERR(m) : err, es);
2728		err = -EIO;
2729		goto bad_out;
2730	}
2731	/* Get the size for the shrunk mapping pairs array for the runlist. */
2732	mp_size = ntfs_get_size_for_mapping_pairs(vol, ni->runlist.rl, 0, -1);
2733	if (unlikely(mp_size <= 0)) {
2734		ntfs_error(vol->sb, "Cannot shrink allocation of inode 0x%lx, "
2735				"attribute type 0x%x, because determining the "
2736				"size for the mapping pairs failed with error "
2737				"code %i.%s", vi->i_ino,
2738				(unsigned)le32_to_cpu(ni->type), mp_size, es);
2739		err = -EIO;
2740		goto bad_out;
2741	}
2742	/*
2743	 * Shrink the attribute record for the new mapping pairs array.  Note,
2744	 * this cannot fail since we are making the attribute smaller thus by
2745	 * definition there is enough space to do so.
2746	 */
2747	attr_len = le32_to_cpu(a->length);
2748	err = ntfs_attr_record_resize(m, a, mp_size +
2749			le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
2750	BUG_ON(err);
2751	/*
2752	 * Generate the mapping pairs array directly into the attribute record.
2753	 */
2754	err = ntfs_mapping_pairs_build(vol, (u8*)a +
2755			le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
2756			mp_size, ni->runlist.rl, 0, -1, NULL);
2757	if (unlikely(err)) {
2758		ntfs_error(vol->sb, "Cannot shrink allocation of inode 0x%lx, "
2759				"attribute type 0x%x, because building the "
2760				"mapping pairs failed with error code %i.%s",
2761				vi->i_ino, (unsigned)le32_to_cpu(ni->type),
2762				err, es);
2763		err = -EIO;
2764		goto bad_out;
2765	}
2766	/* Update the allocated/compressed size as well as the highest vcn. */
2767	a->data.non_resident.highest_vcn = cpu_to_sle64((new_alloc_size >>
2768			vol->cluster_size_bits) - 1);
2769	write_lock_irqsave(&ni->size_lock, flags);
2770	ni->allocated_size = new_alloc_size;
2771	a->data.non_resident.allocated_size = cpu_to_sle64(new_alloc_size);
2772	if (NInoSparse(ni) || NInoCompressed(ni)) {
2773		if (nr_freed) {
2774			ni->itype.compressed.size -= nr_freed <<
2775					vol->cluster_size_bits;
2776			BUG_ON(ni->itype.compressed.size < 0);
2777			a->data.non_resident.compressed_size = cpu_to_sle64(
2778					ni->itype.compressed.size);
2779			vi->i_blocks = ni->itype.compressed.size >> 9;
2780		}
2781	} else
2782		vi->i_blocks = new_alloc_size >> 9;
2783	write_unlock_irqrestore(&ni->size_lock, flags);
2784	/*
2785	 * We have shrunk the allocation.  If this is a shrinking truncate we
2786	 * have already dealt with the initialized_size and the data_size above
2787	 * and we are done.  If the truncate is only changing the allocation
2788	 * and not the data_size, we are also done.  If this is an extending
2789	 * truncate, need to extend the data_size now which is ensured by the
2790	 * fact that @size_change is positive.
2791	 */
2792alloc_done:
2793	/*
2794	 * If the size is growing, need to update it now.  If it is shrinking,
2795	 * we have already updated it above (before the allocation change).
2796	 */
2797	if (size_change > 0)
2798		a->data.non_resident.data_size = cpu_to_sle64(new_size);
2799	/* Ensure the modified mft record is written out. */
2800	flush_dcache_mft_record_page(ctx->ntfs_ino);
2801	mark_mft_record_dirty(ctx->ntfs_ino);
2802unm_done:
2803	ntfs_attr_put_search_ctx(ctx);
2804	unmap_mft_record(base_ni);
2805	up_write(&ni->runlist.lock);
2806done:
2807	/* Update the mtime and ctime on the base inode. */
2808	/* normally ->truncate shouldn't update ctime or mtime,
2809	 * but ntfs did before so it got a copy & paste version
2810	 * of file_update_time.  one day someone should fix this
2811	 * for real.
2812	 */
2813	if (!IS_NOCMTIME(VFS_I(base_ni)) && !IS_RDONLY(VFS_I(base_ni))) {
2814		struct timespec now = current_fs_time(VFS_I(base_ni)->i_sb);
2815		int sync_it = 0;
2816
2817		if (!timespec_equal(&VFS_I(base_ni)->i_mtime, &now) ||
2818		    !timespec_equal(&VFS_I(base_ni)->i_ctime, &now))
2819			sync_it = 1;
2820		VFS_I(base_ni)->i_mtime = now;
2821		VFS_I(base_ni)->i_ctime = now;
2822
2823		if (sync_it)
2824			mark_inode_dirty_sync(VFS_I(base_ni));
2825	}
2826
2827	if (likely(!err)) {
2828		NInoClearTruncateFailed(ni);
2829		ntfs_debug("Done.");
2830	}
2831	return err;
2832old_bad_out:
2833	old_size = -1;
2834bad_out:
2835	if (err != -ENOMEM && err != -EOPNOTSUPP)
2836		NVolSetErrors(vol);
2837	if (err != -EOPNOTSUPP)
2838		NInoSetTruncateFailed(ni);
2839	else if (old_size >= 0)
2840		i_size_write(vi, old_size);
2841err_out:
2842	if (ctx)
2843		ntfs_attr_put_search_ctx(ctx);
2844	if (m)
2845		unmap_mft_record(base_ni);
2846	up_write(&ni->runlist.lock);
2847out:
2848	ntfs_debug("Failed.  Returning error code %i.", err);
2849	return err;
2850conv_err_out:
2851	if (err != -ENOMEM && err != -EOPNOTSUPP)
2852		NVolSetErrors(vol);
2853	if (err != -EOPNOTSUPP)
2854		NInoSetTruncateFailed(ni);
2855	else
2856		i_size_write(vi, old_size);
2857	goto out;
2858}
2859
2860/**
2861 * ntfs_truncate_vfs - wrapper for ntfs_truncate() that has no return value
2862 * @vi:		inode for which the i_size was changed
2863 *
2864 * Wrapper for ntfs_truncate() that has no return value.
2865 *
2866 * See ntfs_truncate() description above for details.
2867 */
2868#ifdef NTFS_RW
2869void ntfs_truncate_vfs(struct inode *vi) {
2870	ntfs_truncate(vi);
2871}
2872#endif
2873
2874/**
2875 * ntfs_setattr - called from notify_change() when an attribute is being changed
2876 * @dentry:	dentry whose attributes to change
2877 * @attr:	structure describing the attributes and the changes
2878 *
2879 * We have to trap VFS attempts to truncate the file described by @dentry as
2880 * soon as possible, because we do not implement changes in i_size yet.  So we
2881 * abort all i_size changes here.
2882 *
2883 * We also abort all changes of user, group, and mode as we do not implement
2884 * the NTFS ACLs yet.
2885 *
2886 * Called with ->i_mutex held.
2887 */
2888int ntfs_setattr(struct dentry *dentry, struct iattr *attr)
2889{
2890	struct inode *vi = dentry->d_inode;
2891	int err;
2892	unsigned int ia_valid = attr->ia_valid;
2893
2894	err = inode_change_ok(vi, attr);
2895	if (err)
2896		goto out;
2897	/* We do not support NTFS ACLs yet. */
2898	if (ia_valid & (ATTR_UID | ATTR_GID | ATTR_MODE)) {
2899		ntfs_warning(vi->i_sb, "Changes in user/group/mode are not "
2900				"supported yet, ignoring.");
2901		err = -EOPNOTSUPP;
2902		goto out;
2903	}
2904	if (ia_valid & ATTR_SIZE) {
2905		if (attr->ia_size != i_size_read(vi)) {
2906			ntfs_inode *ni = NTFS_I(vi);
2907			/*
2908			 * FIXME: For now we do not support resizing of
2909			 * compressed or encrypted files yet.
2910			 */
2911			if (NInoCompressed(ni) || NInoEncrypted(ni)) {
2912				ntfs_warning(vi->i_sb, "Changes in inode size "
2913						"are not supported yet for "
2914						"%s files, ignoring.",
2915						NInoCompressed(ni) ?
2916						"compressed" : "encrypted");
2917				err = -EOPNOTSUPP;
2918			} else {
2919				truncate_setsize(vi, attr->ia_size);
2920				ntfs_truncate_vfs(vi);
2921			}
2922			if (err || ia_valid == ATTR_SIZE)
2923				goto out;
2924		} else {
2925			/*
2926			 * We skipped the truncate but must still update
2927			 * timestamps.
2928			 */
2929			ia_valid |= ATTR_MTIME | ATTR_CTIME;
2930		}
2931	}
2932	if (ia_valid & ATTR_ATIME)
2933		vi->i_atime = timespec_trunc(attr->ia_atime,
2934				vi->i_sb->s_time_gran);
2935	if (ia_valid & ATTR_MTIME)
2936		vi->i_mtime = timespec_trunc(attr->ia_mtime,
2937				vi->i_sb->s_time_gran);
2938	if (ia_valid & ATTR_CTIME)
2939		vi->i_ctime = timespec_trunc(attr->ia_ctime,
2940				vi->i_sb->s_time_gran);
2941	mark_inode_dirty(vi);
2942out:
2943	return err;
2944}
2945
2946/**
2947 * ntfs_write_inode - write out a dirty inode
2948 * @vi:		inode to write out
2949 * @sync:	if true, write out synchronously
2950 *
2951 * Write out a dirty inode to disk including any extent inodes if present.
2952 *
2953 * If @sync is true, commit the inode to disk and wait for io completion.  This
2954 * is done using write_mft_record().
2955 *
2956 * If @sync is false, just schedule the write to happen but do not wait for i/o
2957 * completion.  In 2.6 kernels, scheduling usually happens just by virtue of
2958 * marking the page (and in this case mft record) dirty but we do not implement
2959 * this yet as write_mft_record() largely ignores the @sync parameter and
2960 * always performs synchronous writes.
2961 *
2962 * Return 0 on success and -errno on error.
2963 */
2964int __ntfs_write_inode(struct inode *vi, int sync)
2965{
2966	sle64 nt;
2967	ntfs_inode *ni = NTFS_I(vi);
2968	ntfs_attr_search_ctx *ctx;
2969	MFT_RECORD *m;
2970	STANDARD_INFORMATION *si;
2971	int err = 0;
2972	bool modified = false;
2973
2974	ntfs_debug("Entering for %sinode 0x%lx.", NInoAttr(ni) ? "attr " : "",
2975			vi->i_ino);
2976	/*
2977	 * Dirty attribute inodes are written via their real inodes so just
2978	 * clean them here.  Access time updates are taken care off when the
2979	 * real inode is written.
2980	 */
2981	if (NInoAttr(ni)) {
2982		NInoClearDirty(ni);
2983		ntfs_debug("Done.");
2984		return 0;
2985	}
2986	/* Map, pin, and lock the mft record belonging to the inode. */
2987	m = map_mft_record(ni);
2988	if (IS_ERR(m)) {
2989		err = PTR_ERR(m);
2990		goto err_out;
2991	}
2992	/* Update the access times in the standard information attribute. */
2993	ctx = ntfs_attr_get_search_ctx(ni, m);
2994	if (unlikely(!ctx)) {
2995		err = -ENOMEM;
2996		goto unm_err_out;
2997	}
2998	err = ntfs_attr_lookup(AT_STANDARD_INFORMATION, NULL, 0,
2999			CASE_SENSITIVE, 0, NULL, 0, ctx);
3000	if (unlikely(err)) {
3001		ntfs_attr_put_search_ctx(ctx);
3002		goto unm_err_out;
3003	}
3004	si = (STANDARD_INFORMATION*)((u8*)ctx->attr +
3005			le16_to_cpu(ctx->attr->data.resident.value_offset));
3006	/* Update the access times if they have changed. */
3007	nt = utc2ntfs(vi->i_mtime);
3008	if (si->last_data_change_time != nt) {
3009		ntfs_debug("Updating mtime for inode 0x%lx: old = 0x%llx, "
3010				"new = 0x%llx", vi->i_ino, (long long)
3011				sle64_to_cpu(si->last_data_change_time),
3012				(long long)sle64_to_cpu(nt));
3013		si->last_data_change_time = nt;
3014		modified = true;
3015	}
3016	nt = utc2ntfs(vi->i_ctime);
3017	if (si->last_mft_change_time != nt) {
3018		ntfs_debug("Updating ctime for inode 0x%lx: old = 0x%llx, "
3019				"new = 0x%llx", vi->i_ino, (long long)
3020				sle64_to_cpu(si->last_mft_change_time),
3021				(long long)sle64_to_cpu(nt));
3022		si->last_mft_change_time = nt;
3023		modified = true;
3024	}
3025	nt = utc2ntfs(vi->i_atime);
3026	if (si->last_access_time != nt) {
3027		ntfs_debug("Updating atime for inode 0x%lx: old = 0x%llx, "
3028				"new = 0x%llx", vi->i_ino,
3029				(long long)sle64_to_cpu(si->last_access_time),
3030				(long long)sle64_to_cpu(nt));
3031		si->last_access_time = nt;
3032		modified = true;
3033	}
3034	/*
3035	 * If we just modified the standard information attribute we need to
3036	 * mark the mft record it is in dirty.  We do this manually so that
3037	 * mark_inode_dirty() is not called which would redirty the inode and
3038	 * hence result in an infinite loop of trying to write the inode.
3039	 * There is no need to mark the base inode nor the base mft record
3040	 * dirty, since we are going to write this mft record below in any case
3041	 * and the base mft record may actually not have been modified so it
3042	 * might not need to be written out.
3043	 * NOTE: It is not a problem when the inode for $MFT itself is being
3044	 * written out as mark_ntfs_record_dirty() will only set I_DIRTY_PAGES
3045	 * on the $MFT inode and hence ntfs_write_inode() will not be
3046	 * re-invoked because of it which in turn is ok since the dirtied mft
3047	 * record will be cleaned and written out to disk below, i.e. before
3048	 * this function returns.
3049	 */
3050	if (modified) {
3051		flush_dcache_mft_record_page(ctx->ntfs_ino);
3052		if (!NInoTestSetDirty(ctx->ntfs_ino))
3053			mark_ntfs_record_dirty(ctx->ntfs_ino->page,
3054					ctx->ntfs_ino->page_ofs);
3055	}
3056	ntfs_attr_put_search_ctx(ctx);
3057	/* Now the access times are updated, write the base mft record. */
3058	if (NInoDirty(ni))
3059		err = write_mft_record(ni, m, sync);
3060	/* Write all attached extent mft records. */
3061	mutex_lock(&ni->extent_lock);
3062	if (ni->nr_extents > 0) {
3063		ntfs_inode **extent_nis = ni->ext.extent_ntfs_inos;
3064		int i;
3065
3066		ntfs_debug("Writing %i extent inodes.", ni->nr_extents);
3067		for (i = 0; i < ni->nr_extents; i++) {
3068			ntfs_inode *tni = extent_nis[i];
3069
3070			if (NInoDirty(tni)) {
3071				MFT_RECORD *tm = map_mft_record(tni);
3072				int ret;
3073
3074				if (IS_ERR(tm)) {
3075					if (!err || err == -ENOMEM)
3076						err = PTR_ERR(tm);
3077					continue;
3078				}
3079				ret = write_mft_record(tni, tm, sync);
3080				unmap_mft_record(tni);
3081				if (unlikely(ret)) {
3082					if (!err || err == -ENOMEM)
3083						err = ret;
3084				}
3085			}
3086		}
3087	}
3088	mutex_unlock(&ni->extent_lock);
3089	unmap_mft_record(ni);
3090	if (unlikely(err))
3091		goto err_out;
3092	ntfs_debug("Done.");
3093	return 0;
3094unm_err_out:
3095	unmap_mft_record(ni);
3096err_out:
3097	if (err == -ENOMEM) {
3098		ntfs_warning(vi->i_sb, "Not enough memory to write inode.  "
3099				"Marking the inode dirty again, so the VFS "
3100				"retries later.");
3101		mark_inode_dirty(vi);
3102	} else {
3103		ntfs_error(vi->i_sb, "Failed (error %i):  Run chkdsk.", -err);
3104		NVolSetErrors(ni->vol);
3105	}
3106	return err;
3107}
3108
3109#endif /* NTFS_RW */