1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * This file is part of UBIFS.
   4 *
   5 * Copyright (C) 2006-2008 Nokia Corporation.
   6 *
   7 * Authors: Adrian Hunter
   8 *          Artem Bityutskiy (Битюцкий Артём)
   9 */
  10
  11/*
  12 * This file implements the functions that access LEB properties and their
  13 * categories. LEBs are categorized based on the needs of UBIFS, and the
  14 * categories are stored as either heaps or lists to provide a fast way of
  15 * finding a LEB in a particular category. For example, UBIFS may need to find
  16 * an empty LEB for the journal, or a very dirty LEB for garbage collection.
  17 */
  18
  19#include "ubifs.h"
  20
  21/**
  22 * get_heap_comp_val - get the LEB properties value for heap comparisons.
  23 * @lprops: LEB properties
  24 * @cat: LEB category
  25 */
  26static int get_heap_comp_val(struct ubifs_lprops *lprops, int cat)
  27{
  28	switch (cat) {
  29	case LPROPS_FREE:
  30		return lprops->free;
  31	case LPROPS_DIRTY_IDX:
  32		return lprops->free + lprops->dirty;
  33	default:
  34		return lprops->dirty;
  35	}
  36}
  37
  38/**
  39 * move_up_lpt_heap - move a new heap entry up as far as possible.
  40 * @c: UBIFS file-system description object
  41 * @heap: LEB category heap
  42 * @lprops: LEB properties to move
  43 * @cat: LEB category
  44 *
  45 * New entries to a heap are added at the bottom and then moved up until the
  46 * parent's value is greater.  In the case of LPT's category heaps, the value
  47 * is either the amount of free space or the amount of dirty space, depending
  48 * on the category.
  49 */
  50static void move_up_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
  51			     struct ubifs_lprops *lprops, int cat)
  52{
  53	int val1, val2, hpos;
  54
  55	hpos = lprops->hpos;
  56	if (!hpos)
  57		return; /* Already top of the heap */
  58	val1 = get_heap_comp_val(lprops, cat);
  59	/* Compare to parent and, if greater, move up the heap */
  60	do {
  61		int ppos = (hpos - 1) / 2;
  62
  63		val2 = get_heap_comp_val(heap->arr[ppos], cat);
  64		if (val2 >= val1)
  65			return;
  66		/* Greater than parent so move up */
  67		heap->arr[ppos]->hpos = hpos;
  68		heap->arr[hpos] = heap->arr[ppos];
  69		heap->arr[ppos] = lprops;
  70		lprops->hpos = ppos;
  71		hpos = ppos;
  72	} while (hpos);
  73}
  74
  75/**
  76 * adjust_lpt_heap - move a changed heap entry up or down the heap.
  77 * @c: UBIFS file-system description object
  78 * @heap: LEB category heap
  79 * @lprops: LEB properties to move
  80 * @hpos: heap position of @lprops
  81 * @cat: LEB category
  82 *
  83 * Changed entries in a heap are moved up or down until the parent's value is
  84 * greater.  In the case of LPT's category heaps, the value is either the amount
  85 * of free space or the amount of dirty space, depending on the category.
  86 */
  87static void adjust_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
  88			    struct ubifs_lprops *lprops, int hpos, int cat)
  89{
  90	int val1, val2, val3, cpos;
  91
  92	val1 = get_heap_comp_val(lprops, cat);
  93	/* Compare to parent and, if greater than parent, move up the heap */
  94	if (hpos) {
  95		int ppos = (hpos - 1) / 2;
  96
  97		val2 = get_heap_comp_val(heap->arr[ppos], cat);
  98		if (val1 > val2) {
  99			/* Greater than parent so move up */
 100			while (1) {
 101				heap->arr[ppos]->hpos = hpos;
 102				heap->arr[hpos] = heap->arr[ppos];
 103				heap->arr[ppos] = lprops;
 104				lprops->hpos = ppos;
 105				hpos = ppos;
 106				if (!hpos)
 107					return;
 108				ppos = (hpos - 1) / 2;
 109				val2 = get_heap_comp_val(heap->arr[ppos], cat);
 110				if (val1 <= val2)
 111					return;
 112				/* Still greater than parent so keep going */
 113			}
 114		}
 115	}
 116
 117	/* Not greater than parent, so compare to children */
 118	while (1) {
 119		/* Compare to left child */
 120		cpos = hpos * 2 + 1;
 121		if (cpos >= heap->cnt)
 122			return;
 123		val2 = get_heap_comp_val(heap->arr[cpos], cat);
 124		if (val1 < val2) {
 125			/* Less than left child, so promote biggest child */
 126			if (cpos + 1 < heap->cnt) {
 127				val3 = get_heap_comp_val(heap->arr[cpos + 1],
 128							 cat);
 129				if (val3 > val2)
 130					cpos += 1; /* Right child is bigger */
 131			}
 132			heap->arr[cpos]->hpos = hpos;
 133			heap->arr[hpos] = heap->arr[cpos];
 134			heap->arr[cpos] = lprops;
 135			lprops->hpos = cpos;
 136			hpos = cpos;
 137			continue;
 138		}
 139		/* Compare to right child */
 140		cpos += 1;
 141		if (cpos >= heap->cnt)
 142			return;
 143		val3 = get_heap_comp_val(heap->arr[cpos], cat);
 144		if (val1 < val3) {
 145			/* Less than right child, so promote right child */
 146			heap->arr[cpos]->hpos = hpos;
 147			heap->arr[hpos] = heap->arr[cpos];
 148			heap->arr[cpos] = lprops;
 149			lprops->hpos = cpos;
 150			hpos = cpos;
 151			continue;
 152		}
 153		return;
 154	}
 155}
 156
 157/**
 158 * add_to_lpt_heap - add LEB properties to a LEB category heap.
 159 * @c: UBIFS file-system description object
 160 * @lprops: LEB properties to add
 161 * @cat: LEB category
 162 *
 163 * This function returns %1 if @lprops is added to the heap for LEB category
 164 * @cat, otherwise %0 is returned because the heap is full.
 165 */
 166static int add_to_lpt_heap(struct ubifs_info *c, struct ubifs_lprops *lprops,
 167			   int cat)
 168{
 169	struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
 170
 171	if (heap->cnt >= heap->max_cnt) {
 172		const int b = LPT_HEAP_SZ / 2 - 1;
 173		int cpos, val1, val2;
 174
 175		/* Compare to some other LEB on the bottom of heap */
 176		/* Pick a position kind of randomly */
 177		cpos = (((size_t)lprops >> 4) & b) + b;
 178		ubifs_assert(c, cpos >= b);
 179		ubifs_assert(c, cpos < LPT_HEAP_SZ);
 180		ubifs_assert(c, cpos < heap->cnt);
 181
 182		val1 = get_heap_comp_val(lprops, cat);
 183		val2 = get_heap_comp_val(heap->arr[cpos], cat);
 184		if (val1 > val2) {
 185			struct ubifs_lprops *lp;
 186
 187			lp = heap->arr[cpos];
 188			lp->flags &= ~LPROPS_CAT_MASK;
 189			lp->flags |= LPROPS_UNCAT;
 190			list_add(&lp->list, &c->uncat_list);
 191			lprops->hpos = cpos;
 192			heap->arr[cpos] = lprops;
 193			move_up_lpt_heap(c, heap, lprops, cat);
 194			dbg_check_heap(c, heap, cat, lprops->hpos);
 195			return 1; /* Added to heap */
 196		}
 197		dbg_check_heap(c, heap, cat, -1);
 198		return 0; /* Not added to heap */
 199	} else {
 200		lprops->hpos = heap->cnt++;
 201		heap->arr[lprops->hpos] = lprops;
 202		move_up_lpt_heap(c, heap, lprops, cat);
 203		dbg_check_heap(c, heap, cat, lprops->hpos);
 204		return 1; /* Added to heap */
 205	}
 206}
 207
 208/**
 209 * remove_from_lpt_heap - remove LEB properties from a LEB category heap.
 210 * @c: UBIFS file-system description object
 211 * @lprops: LEB properties to remove
 212 * @cat: LEB category
 213 */
 214static void remove_from_lpt_heap(struct ubifs_info *c,
 215				 struct ubifs_lprops *lprops, int cat)
 216{
 217	struct ubifs_lpt_heap *heap;
 218	int hpos = lprops->hpos;
 219
 220	heap = &c->lpt_heap[cat - 1];
 221	ubifs_assert(c, hpos >= 0 && hpos < heap->cnt);
 222	ubifs_assert(c, heap->arr[hpos] == lprops);
 223	heap->cnt -= 1;
 224	if (hpos < heap->cnt) {
 225		heap->arr[hpos] = heap->arr[heap->cnt];
 226		heap->arr[hpos]->hpos = hpos;
 227		adjust_lpt_heap(c, heap, heap->arr[hpos], hpos, cat);
 228	}
 229	dbg_check_heap(c, heap, cat, -1);
 230}
 231
 232/**
 233 * lpt_heap_replace - replace lprops in a category heap.
 234 * @c: UBIFS file-system description object
 235 * @new_lprops: LEB properties with which to replace
 236 * @cat: LEB category
 237 *
 238 * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
 239 * and the lprops that the pnode contains.  When that happens, references in
 240 * the category heaps to those lprops must be updated to point to the new
 241 * lprops.  This function does that.
 242 */
 243static void lpt_heap_replace(struct ubifs_info *c,
 244			     struct ubifs_lprops *new_lprops, int cat)
 245{
 246	struct ubifs_lpt_heap *heap;
 247	int hpos = new_lprops->hpos;
 248
 249	heap = &c->lpt_heap[cat - 1];
 250	heap->arr[hpos] = new_lprops;
 251}
 252
 253/**
 254 * ubifs_add_to_cat - add LEB properties to a category list or heap.
 255 * @c: UBIFS file-system description object
 256 * @lprops: LEB properties to add
 257 * @cat: LEB category to which to add
 258 *
 259 * LEB properties are categorized to enable fast find operations.
 260 */
 261void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
 262		      int cat)
 263{
 264	switch (cat) {
 265	case LPROPS_DIRTY:
 266	case LPROPS_DIRTY_IDX:
 267	case LPROPS_FREE:
 268		if (add_to_lpt_heap(c, lprops, cat))
 269			break;
 270		/* No more room on heap so make it un-categorized */
 271		cat = LPROPS_UNCAT;
 272		/* Fall through */
 273	case LPROPS_UNCAT:
 274		list_add(&lprops->list, &c->uncat_list);
 275		break;
 276	case LPROPS_EMPTY:
 277		list_add(&lprops->list, &c->empty_list);
 278		break;
 279	case LPROPS_FREEABLE:
 280		list_add(&lprops->list, &c->freeable_list);
 281		c->freeable_cnt += 1;
 282		break;
 283	case LPROPS_FRDI_IDX:
 284		list_add(&lprops->list, &c->frdi_idx_list);
 285		break;
 286	default:
 287		ubifs_assert(c, 0);
 288	}
 289
 290	lprops->flags &= ~LPROPS_CAT_MASK;
 291	lprops->flags |= cat;
 292	c->in_a_category_cnt += 1;
 293	ubifs_assert(c, c->in_a_category_cnt <= c->main_lebs);
 294}
 295
 296/**
 297 * ubifs_remove_from_cat - remove LEB properties from a category list or heap.
 298 * @c: UBIFS file-system description object
 299 * @lprops: LEB properties to remove
 300 * @cat: LEB category from which to remove
 301 *
 302 * LEB properties are categorized to enable fast find operations.
 303 */
 304static void ubifs_remove_from_cat(struct ubifs_info *c,
 305				  struct ubifs_lprops *lprops, int cat)
 306{
 307	switch (cat) {
 308	case LPROPS_DIRTY:
 309	case LPROPS_DIRTY_IDX:
 310	case LPROPS_FREE:
 311		remove_from_lpt_heap(c, lprops, cat);
 312		break;
 313	case LPROPS_FREEABLE:
 314		c->freeable_cnt -= 1;
 315		ubifs_assert(c, c->freeable_cnt >= 0);
 316		/* Fall through */
 317	case LPROPS_UNCAT:
 318	case LPROPS_EMPTY:
 319	case LPROPS_FRDI_IDX:
 320		ubifs_assert(c, !list_empty(&lprops->list));
 321		list_del(&lprops->list);
 322		break;
 323	default:
 324		ubifs_assert(c, 0);
 325	}
 326
 327	c->in_a_category_cnt -= 1;
 328	ubifs_assert(c, c->in_a_category_cnt >= 0);
 329}
 330
 331/**
 332 * ubifs_replace_cat - replace lprops in a category list or heap.
 333 * @c: UBIFS file-system description object
 334 * @old_lprops: LEB properties to replace
 335 * @new_lprops: LEB properties with which to replace
 336 *
 337 * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
 338 * and the lprops that the pnode contains. When that happens, references in
 339 * category lists and heaps must be replaced. This function does that.
 340 */
 341void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
 342		       struct ubifs_lprops *new_lprops)
 343{
 344	int cat;
 345
 346	cat = new_lprops->flags & LPROPS_CAT_MASK;
 347	switch (cat) {
 348	case LPROPS_DIRTY:
 349	case LPROPS_DIRTY_IDX:
 350	case LPROPS_FREE:
 351		lpt_heap_replace(c, new_lprops, cat);
 352		break;
 353	case LPROPS_UNCAT:
 354	case LPROPS_EMPTY:
 355	case LPROPS_FREEABLE:
 356	case LPROPS_FRDI_IDX:
 357		list_replace(&old_lprops->list, &new_lprops->list);
 358		break;
 359	default:
 360		ubifs_assert(c, 0);
 361	}
 362}
 363
 364/**
 365 * ubifs_ensure_cat - ensure LEB properties are categorized.
 366 * @c: UBIFS file-system description object
 367 * @lprops: LEB properties
 368 *
 369 * A LEB may have fallen off of the bottom of a heap, and ended up as
 370 * un-categorized even though it has enough space for us now. If that is the
 371 * case this function will put the LEB back onto a heap.
 372 */
 373void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops)
 374{
 375	int cat = lprops->flags & LPROPS_CAT_MASK;
 376
 377	if (cat != LPROPS_UNCAT)
 378		return;
 379	cat = ubifs_categorize_lprops(c, lprops);
 380	if (cat == LPROPS_UNCAT)
 381		return;
 382	ubifs_remove_from_cat(c, lprops, LPROPS_UNCAT);
 383	ubifs_add_to_cat(c, lprops, cat);
 384}
 385
 386/**
 387 * ubifs_categorize_lprops - categorize LEB properties.
 388 * @c: UBIFS file-system description object
 389 * @lprops: LEB properties to categorize
 390 *
 391 * LEB properties are categorized to enable fast find operations. This function
 392 * returns the LEB category to which the LEB properties belong. Note however
 393 * that if the LEB category is stored as a heap and the heap is full, the
 394 * LEB properties may have their category changed to %LPROPS_UNCAT.
 395 */
 396int ubifs_categorize_lprops(const struct ubifs_info *c,
 397			    const struct ubifs_lprops *lprops)
 398{
 399	if (lprops->flags & LPROPS_TAKEN)
 400		return LPROPS_UNCAT;
 401
 402	if (lprops->free == c->leb_size) {
 403		ubifs_assert(c, !(lprops->flags & LPROPS_INDEX));
 404		return LPROPS_EMPTY;
 405	}
 406
 407	if (lprops->free + lprops->dirty == c->leb_size) {
 408		if (lprops->flags & LPROPS_INDEX)
 409			return LPROPS_FRDI_IDX;
 410		else
 411			return LPROPS_FREEABLE;
 412	}
 413
 414	if (lprops->flags & LPROPS_INDEX) {
 415		if (lprops->dirty + lprops->free >= c->min_idx_node_sz)
 416			return LPROPS_DIRTY_IDX;
 417	} else {
 418		if (lprops->dirty >= c->dead_wm &&
 419		    lprops->dirty > lprops->free)
 420			return LPROPS_DIRTY;
 421		if (lprops->free > 0)
 422			return LPROPS_FREE;
 423	}
 424
 425	return LPROPS_UNCAT;
 426}
 427
 428/**
 429 * change_category - change LEB properties category.
 430 * @c: UBIFS file-system description object
 431 * @lprops: LEB properties to re-categorize
 432 *
 433 * LEB properties are categorized to enable fast find operations. When the LEB
 434 * properties change they must be re-categorized.
 435 */
 436static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops)
 437{
 438	int old_cat = lprops->flags & LPROPS_CAT_MASK;
 439	int new_cat = ubifs_categorize_lprops(c, lprops);
 440
 441	if (old_cat == new_cat) {
 442		struct ubifs_lpt_heap *heap;
 443
 444		/* lprops on a heap now must be moved up or down */
 445		if (new_cat < 1 || new_cat > LPROPS_HEAP_CNT)
 446			return; /* Not on a heap */
 447		heap = &c->lpt_heap[new_cat - 1];
 448		adjust_lpt_heap(c, heap, lprops, lprops->hpos, new_cat);
 449	} else {
 450		ubifs_remove_from_cat(c, lprops, old_cat);
 451		ubifs_add_to_cat(c, lprops, new_cat);
 452	}
 453}
 454
 455/**
 456 * ubifs_calc_dark - calculate LEB dark space size.
 457 * @c: the UBIFS file-system description object
 458 * @spc: amount of free and dirty space in the LEB
 459 *
 460 * This function calculates and returns amount of dark space in an LEB which
 461 * has @spc bytes of free and dirty space.
 462 *
 463 * UBIFS is trying to account the space which might not be usable, and this
 464 * space is called "dark space". For example, if an LEB has only %512 free
 465 * bytes, it is dark space, because it cannot fit a large data node.
 466 */
 467int ubifs_calc_dark(const struct ubifs_info *c, int spc)
 468{
 469	ubifs_assert(c, !(spc & 7));
 470
 471	if (spc < c->dark_wm)
 472		return spc;
 473
 474	/*
 475	 * If we have slightly more space then the dark space watermark, we can
 476	 * anyway safely assume it we'll be able to write a node of the
 477	 * smallest size there.
 478	 */
 479	if (spc - c->dark_wm < MIN_WRITE_SZ)
 480		return spc - MIN_WRITE_SZ;
 481
 482	return c->dark_wm;
 483}
 484
 485/**
 486 * is_lprops_dirty - determine if LEB properties are dirty.
 487 * @c: the UBIFS file-system description object
 488 * @lprops: LEB properties to test
 489 */
 490static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops)
 491{
 492	struct ubifs_pnode *pnode;
 493	int pos;
 494
 495	pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1);
 496	pnode = (struct ubifs_pnode *)container_of(lprops - pos,
 497						   struct ubifs_pnode,
 498						   lprops[0]);
 499	return !test_bit(COW_CNODE, &pnode->flags) &&
 500	       test_bit(DIRTY_CNODE, &pnode->flags);
 501}
 502
 503/**
 504 * ubifs_change_lp - change LEB properties.
 505 * @c: the UBIFS file-system description object
 506 * @lp: LEB properties to change
 507 * @free: new free space amount
 508 * @dirty: new dirty space amount
 509 * @flags: new flags
 510 * @idx_gc_cnt: change to the count of @idx_gc list
 511 *
 512 * This function changes LEB properties (@free, @dirty or @flag). However, the
 513 * property which has the %LPROPS_NC value is not changed. Returns a pointer to
 514 * the updated LEB properties on success and a negative error code on failure.
 515 *
 516 * Note, the LEB properties may have had to be copied (due to COW) and
 517 * consequently the pointer returned may not be the same as the pointer
 518 * passed.
 519 */
 520const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
 521					   const struct ubifs_lprops *lp,
 522					   int free, int dirty, int flags,
 523					   int idx_gc_cnt)
 524{
 525	/*
 526	 * This is the only function that is allowed to change lprops, so we
 527	 * discard the "const" qualifier.
 528	 */
 529	struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp;
 530
 531	dbg_lp("LEB %d, free %d, dirty %d, flags %d",
 532	       lprops->lnum, free, dirty, flags);
 533
 534	ubifs_assert(c, mutex_is_locked(&c->lp_mutex));
 535	ubifs_assert(c, c->lst.empty_lebs >= 0 &&
 536		     c->lst.empty_lebs <= c->main_lebs);
 537	ubifs_assert(c, c->freeable_cnt >= 0);
 538	ubifs_assert(c, c->freeable_cnt <= c->main_lebs);
 539	ubifs_assert(c, c->lst.taken_empty_lebs >= 0);
 540	ubifs_assert(c, c->lst.taken_empty_lebs <= c->lst.empty_lebs);
 541	ubifs_assert(c, !(c->lst.total_free & 7) && !(c->lst.total_dirty & 7));
 542	ubifs_assert(c, !(c->lst.total_dead & 7) && !(c->lst.total_dark & 7));
 543	ubifs_assert(c, !(c->lst.total_used & 7));
 544	ubifs_assert(c, free == LPROPS_NC || free >= 0);
 545	ubifs_assert(c, dirty == LPROPS_NC || dirty >= 0);
 546
 547	if (!is_lprops_dirty(c, lprops)) {
 548		lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum);
 549		if (IS_ERR(lprops))
 550			return lprops;
 551	} else
 552		ubifs_assert(c, lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum));
 553
 554	ubifs_assert(c, !(lprops->free & 7) && !(lprops->dirty & 7));
 555
 556	spin_lock(&c->space_lock);
 557	if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
 558		c->lst.taken_empty_lebs -= 1;
 559
 560	if (!(lprops->flags & LPROPS_INDEX)) {
 561		int old_spc;
 562
 563		old_spc = lprops->free + lprops->dirty;
 564		if (old_spc < c->dead_wm)
 565			c->lst.total_dead -= old_spc;
 566		else
 567			c->lst.total_dark -= ubifs_calc_dark(c, old_spc);
 568
 569		c->lst.total_used -= c->leb_size - old_spc;
 570	}
 571
 572	if (free != LPROPS_NC) {
 573		free = ALIGN(free, 8);
 574		c->lst.total_free += free - lprops->free;
 575
 576		/* Increase or decrease empty LEBs counter if needed */
 577		if (free == c->leb_size) {
 578			if (lprops->free != c->leb_size)
 579				c->lst.empty_lebs += 1;
 580		} else if (lprops->free == c->leb_size)
 581			c->lst.empty_lebs -= 1;
 582		lprops->free = free;
 583	}
 584
 585	if (dirty != LPROPS_NC) {
 586		dirty = ALIGN(dirty, 8);
 587		c->lst.total_dirty += dirty - lprops->dirty;
 588		lprops->dirty = dirty;
 589	}
 590
 591	if (flags != LPROPS_NC) {
 592		/* Take care about indexing LEBs counter if needed */
 593		if ((lprops->flags & LPROPS_INDEX)) {
 594			if (!(flags & LPROPS_INDEX))
 595				c->lst.idx_lebs -= 1;
 596		} else if (flags & LPROPS_INDEX)
 597			c->lst.idx_lebs += 1;
 598		lprops->flags = flags;
 599	}
 600
 601	if (!(lprops->flags & LPROPS_INDEX)) {
 602		int new_spc;
 603
 604		new_spc = lprops->free + lprops->dirty;
 605		if (new_spc < c->dead_wm)
 606			c->lst.total_dead += new_spc;
 607		else
 608			c->lst.total_dark += ubifs_calc_dark(c, new_spc);
 609
 610		c->lst.total_used += c->leb_size - new_spc;
 611	}
 612
 613	if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
 614		c->lst.taken_empty_lebs += 1;
 615
 616	change_category(c, lprops);
 617	c->idx_gc_cnt += idx_gc_cnt;
 618	spin_unlock(&c->space_lock);
 619	return lprops;
 620}
 621
 622/**
 623 * ubifs_get_lp_stats - get lprops statistics.
 624 * @c: UBIFS file-system description object
 625 * @lst: return statistics
 626 */
 627void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst)
 628{
 629	spin_lock(&c->space_lock);
 630	memcpy(lst, &c->lst, sizeof(struct ubifs_lp_stats));
 631	spin_unlock(&c->space_lock);
 632}
 633
 634/**
 635 * ubifs_change_one_lp - change LEB properties.
 636 * @c: the UBIFS file-system description object
 637 * @lnum: LEB to change properties for
 638 * @free: amount of free space
 639 * @dirty: amount of dirty space
 640 * @flags_set: flags to set
 641 * @flags_clean: flags to clean
 642 * @idx_gc_cnt: change to the count of idx_gc list
 643 *
 644 * This function changes properties of LEB @lnum. It is a helper wrapper over
 645 * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the
 646 * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and
 647 * a negative error code in case of failure.
 648 */
 649int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
 650			int flags_set, int flags_clean, int idx_gc_cnt)
 651{
 652	int err = 0, flags;
 653	const struct ubifs_lprops *lp;
 654
 655	ubifs_get_lprops(c);
 656
 657	lp = ubifs_lpt_lookup_dirty(c, lnum);
 658	if (IS_ERR(lp)) {
 659		err = PTR_ERR(lp);
 660		goto out;
 661	}
 662
 663	flags = (lp->flags | flags_set) & ~flags_clean;
 664	lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt);
 665	if (IS_ERR(lp))
 666		err = PTR_ERR(lp);
 667
 668out:
 669	ubifs_release_lprops(c);
 670	if (err)
 671		ubifs_err(c, "cannot change properties of LEB %d, error %d",
 672			  lnum, err);
 673	return err;
 674}
 675
 676/**
 677 * ubifs_update_one_lp - update LEB properties.
 678 * @c: the UBIFS file-system description object
 679 * @lnum: LEB to change properties for
 680 * @free: amount of free space
 681 * @dirty: amount of dirty space to add
 682 * @flags_set: flags to set
 683 * @flags_clean: flags to clean
 684 *
 685 * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to
 686 * current dirty space, not substitutes it.
 687 */
 688int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
 689			int flags_set, int flags_clean)
 690{
 691	int err = 0, flags;
 692	const struct ubifs_lprops *lp;
 693
 694	ubifs_get_lprops(c);
 695
 696	lp = ubifs_lpt_lookup_dirty(c, lnum);
 697	if (IS_ERR(lp)) {
 698		err = PTR_ERR(lp);
 699		goto out;
 700	}
 701
 702	flags = (lp->flags | flags_set) & ~flags_clean;
 703	lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0);
 704	if (IS_ERR(lp))
 705		err = PTR_ERR(lp);
 706
 707out:
 708	ubifs_release_lprops(c);
 709	if (err)
 710		ubifs_err(c, "cannot update properties of LEB %d, error %d",
 711			  lnum, err);
 712	return err;
 713}
 714
 715/**
 716 * ubifs_read_one_lp - read LEB properties.
 717 * @c: the UBIFS file-system description object
 718 * @lnum: LEB to read properties for
 719 * @lp: where to store read properties
 720 *
 721 * This helper function reads properties of a LEB @lnum and stores them in @lp.
 722 * Returns zero in case of success and a negative error code in case of
 723 * failure.
 724 */
 725int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp)
 726{
 727	int err = 0;
 728	const struct ubifs_lprops *lpp;
 729
 730	ubifs_get_lprops(c);
 731
 732	lpp = ubifs_lpt_lookup(c, lnum);
 733	if (IS_ERR(lpp)) {
 734		err = PTR_ERR(lpp);
 735		ubifs_err(c, "cannot read properties of LEB %d, error %d",
 736			  lnum, err);
 737		goto out;
 738	}
 739
 740	memcpy(lp, lpp, sizeof(struct ubifs_lprops));
 741
 742out:
 743	ubifs_release_lprops(c);
 744	return err;
 745}
 746
 747/**
 748 * ubifs_fast_find_free - try to find a LEB with free space quickly.
 749 * @c: the UBIFS file-system description object
 750 *
 751 * This function returns LEB properties for a LEB with free space or %NULL if
 752 * the function is unable to find a LEB quickly.
 753 */
 754const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c)
 755{
 756	struct ubifs_lprops *lprops;
 757	struct ubifs_lpt_heap *heap;
 758
 759	ubifs_assert(c, mutex_is_locked(&c->lp_mutex));
 760
 761	heap = &c->lpt_heap[LPROPS_FREE - 1];
 762	if (heap->cnt == 0)
 763		return NULL;
 764
 765	lprops = heap->arr[0];
 766	ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN));
 767	ubifs_assert(c, !(lprops->flags & LPROPS_INDEX));
 768	return lprops;
 769}
 770
 771/**
 772 * ubifs_fast_find_empty - try to find an empty LEB quickly.
 773 * @c: the UBIFS file-system description object
 774 *
 775 * This function returns LEB properties for an empty LEB or %NULL if the
 776 * function is unable to find an empty LEB quickly.
 777 */
 778const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c)
 779{
 780	struct ubifs_lprops *lprops;
 781
 782	ubifs_assert(c, mutex_is_locked(&c->lp_mutex));
 783
 784	if (list_empty(&c->empty_list))
 785		return NULL;
 786
 787	lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list);
 788	ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN));
 789	ubifs_assert(c, !(lprops->flags & LPROPS_INDEX));
 790	ubifs_assert(c, lprops->free == c->leb_size);
 791	return lprops;
 792}
 793
 794/**
 795 * ubifs_fast_find_freeable - try to find a freeable LEB quickly.
 796 * @c: the UBIFS file-system description object
 797 *
 798 * This function returns LEB properties for a freeable LEB or %NULL if the
 799 * function is unable to find a freeable LEB quickly.
 800 */
 801const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c)
 802{
 803	struct ubifs_lprops *lprops;
 804
 805	ubifs_assert(c, mutex_is_locked(&c->lp_mutex));
 806
 807	if (list_empty(&c->freeable_list))
 808		return NULL;
 809
 810	lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list);
 811	ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN));
 812	ubifs_assert(c, !(lprops->flags & LPROPS_INDEX));
 813	ubifs_assert(c, lprops->free + lprops->dirty == c->leb_size);
 814	ubifs_assert(c, c->freeable_cnt > 0);
 815	return lprops;
 816}
 817
 818/**
 819 * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly.
 820 * @c: the UBIFS file-system description object
 821 *
 822 * This function returns LEB properties for a freeable index LEB or %NULL if the
 823 * function is unable to find a freeable index LEB quickly.
 824 */
 825const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c)
 826{
 827	struct ubifs_lprops *lprops;
 828
 829	ubifs_assert(c, mutex_is_locked(&c->lp_mutex));
 830
 831	if (list_empty(&c->frdi_idx_list))
 832		return NULL;
 833
 834	lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list);
 835	ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN));
 836	ubifs_assert(c, (lprops->flags & LPROPS_INDEX));
 837	ubifs_assert(c, lprops->free + lprops->dirty == c->leb_size);
 838	return lprops;
 839}
 840
 841/*
 842 * Everything below is related to debugging.
 843 */
 844
 845/**
 846 * dbg_check_cats - check category heaps and lists.
 847 * @c: UBIFS file-system description object
 848 *
 849 * This function returns %0 on success and a negative error code on failure.
 850 */
 851int dbg_check_cats(struct ubifs_info *c)
 852{
 853	struct ubifs_lprops *lprops;
 854	struct list_head *pos;
 855	int i, cat;
 856
 857	if (!dbg_is_chk_gen(c) && !dbg_is_chk_lprops(c))
 858		return 0;
 859
 860	list_for_each_entry(lprops, &c->empty_list, list) {
 861		if (lprops->free != c->leb_size) {
 862			ubifs_err(c, "non-empty LEB %d on empty list (free %d dirty %d flags %d)",
 863				  lprops->lnum, lprops->free, lprops->dirty,
 864				  lprops->flags);
 865			return -EINVAL;
 866		}
 867		if (lprops->flags & LPROPS_TAKEN) {
 868			ubifs_err(c, "taken LEB %d on empty list (free %d dirty %d flags %d)",
 869				  lprops->lnum, lprops->free, lprops->dirty,
 870				  lprops->flags);
 871			return -EINVAL;
 872		}
 873	}
 874
 875	i = 0;
 876	list_for_each_entry(lprops, &c->freeable_list, list) {
 877		if (lprops->free + lprops->dirty != c->leb_size) {
 878			ubifs_err(c, "non-freeable LEB %d on freeable list (free %d dirty %d flags %d)",
 879				  lprops->lnum, lprops->free, lprops->dirty,
 880				  lprops->flags);
 881			return -EINVAL;
 882		}
 883		if (lprops->flags & LPROPS_TAKEN) {
 884			ubifs_err(c, "taken LEB %d on freeable list (free %d dirty %d flags %d)",
 885				  lprops->lnum, lprops->free, lprops->dirty,
 886				  lprops->flags);
 887			return -EINVAL;
 888		}
 889		i += 1;
 890	}
 891	if (i != c->freeable_cnt) {
 892		ubifs_err(c, "freeable list count %d expected %d", i,
 893			  c->freeable_cnt);
 894		return -EINVAL;
 895	}
 896
 897	i = 0;
 898	list_for_each(pos, &c->idx_gc)
 899		i += 1;
 900	if (i != c->idx_gc_cnt) {
 901		ubifs_err(c, "idx_gc list count %d expected %d", i,
 902			  c->idx_gc_cnt);
 903		return -EINVAL;
 904	}
 905
 906	list_for_each_entry(lprops, &c->frdi_idx_list, list) {
 907		if (lprops->free + lprops->dirty != c->leb_size) {
 908			ubifs_err(c, "non-freeable LEB %d on frdi_idx list (free %d dirty %d flags %d)",
 909				  lprops->lnum, lprops->free, lprops->dirty,
 910				  lprops->flags);
 911			return -EINVAL;
 912		}
 913		if (lprops->flags & LPROPS_TAKEN) {
 914			ubifs_err(c, "taken LEB %d on frdi_idx list (free %d dirty %d flags %d)",
 915				  lprops->lnum, lprops->free, lprops->dirty,
 916				  lprops->flags);
 917			return -EINVAL;
 918		}
 919		if (!(lprops->flags & LPROPS_INDEX)) {
 920			ubifs_err(c, "non-index LEB %d on frdi_idx list (free %d dirty %d flags %d)",
 921				  lprops->lnum, lprops->free, lprops->dirty,
 922				  lprops->flags);
 923			return -EINVAL;
 924		}
 925	}
 926
 927	for (cat = 1; cat <= LPROPS_HEAP_CNT; cat++) {
 928		struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
 929
 930		for (i = 0; i < heap->cnt; i++) {
 931			lprops = heap->arr[i];
 932			if (!lprops) {
 933				ubifs_err(c, "null ptr in LPT heap cat %d", cat);
 934				return -EINVAL;
 935			}
 936			if (lprops->hpos != i) {
 937				ubifs_err(c, "bad ptr in LPT heap cat %d", cat);
 938				return -EINVAL;
 939			}
 940			if (lprops->flags & LPROPS_TAKEN) {
 941				ubifs_err(c, "taken LEB in LPT heap cat %d", cat);
 942				return -EINVAL;
 943			}
 944		}
 945	}
 946
 947	return 0;
 948}
 949
 950void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
 951		    int add_pos)
 952{
 953	int i = 0, j, err = 0;
 954
 955	if (!dbg_is_chk_gen(c) && !dbg_is_chk_lprops(c))
 956		return;
 957
 958	for (i = 0; i < heap->cnt; i++) {
 959		struct ubifs_lprops *lprops = heap->arr[i];
 960		struct ubifs_lprops *lp;
 961
 962		if (i != add_pos)
 963			if ((lprops->flags & LPROPS_CAT_MASK) != cat) {
 964				err = 1;
 965				goto out;
 966			}
 967		if (lprops->hpos != i) {
 968			err = 2;
 969			goto out;
 970		}
 971		lp = ubifs_lpt_lookup(c, lprops->lnum);
 972		if (IS_ERR(lp)) {
 973			err = 3;
 974			goto out;
 975		}
 976		if (lprops != lp) {
 977			ubifs_err(c, "lprops %zx lp %zx lprops->lnum %d lp->lnum %d",
 978				  (size_t)lprops, (size_t)lp, lprops->lnum,
 979				  lp->lnum);
 980			err = 4;
 981			goto out;
 982		}
 983		for (j = 0; j < i; j++) {
 984			lp = heap->arr[j];
 985			if (lp == lprops) {
 986				err = 5;
 987				goto out;
 988			}
 989			if (lp->lnum == lprops->lnum) {
 990				err = 6;
 991				goto out;
 992			}
 993		}
 994	}
 995out:
 996	if (err) {
 997		ubifs_err(c, "failed cat %d hpos %d err %d", cat, i, err);
 998		dump_stack();
 999		ubifs_dump_heap(c, heap, cat);
1000	}
1001}
1002
1003/**
1004 * scan_check_cb - scan callback.
1005 * @c: the UBIFS file-system description object
1006 * @lp: LEB properties to scan
1007 * @in_tree: whether the LEB properties are in main memory
1008 * @lst: lprops statistics to update
1009 *
1010 * This function returns a code that indicates whether the scan should continue
1011 * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
1012 * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
1013 * (%LPT_SCAN_STOP).
1014 */
1015static int scan_check_cb(struct ubifs_info *c,
1016			 const struct ubifs_lprops *lp, int in_tree,
1017			 struct ubifs_lp_stats *lst)
1018{
1019	struct ubifs_scan_leb *sleb;
1020	struct ubifs_scan_node *snod;
1021	int cat, lnum = lp->lnum, is_idx = 0, used = 0, free, dirty, ret;
1022	void *buf = NULL;
1023
1024	cat = lp->flags & LPROPS_CAT_MASK;
1025	if (cat != LPROPS_UNCAT) {
1026		cat = ubifs_categorize_lprops(c, lp);
1027		if (cat != (lp->flags & LPROPS_CAT_MASK)) {
1028			ubifs_err(c, "bad LEB category %d expected %d",
1029				  (lp->flags & LPROPS_CAT_MASK), cat);
1030			return -EINVAL;
1031		}
1032	}
1033
1034	/* Check lp is on its category list (if it has one) */
1035	if (in_tree) {
1036		struct list_head *list = NULL;
1037
1038		switch (cat) {
1039		case LPROPS_EMPTY:
1040			list = &c->empty_list;
1041			break;
1042		case LPROPS_FREEABLE:
1043			list = &c->freeable_list;
1044			break;
1045		case LPROPS_FRDI_IDX:
1046			list = &c->frdi_idx_list;
1047			break;
1048		case LPROPS_UNCAT:
1049			list = &c->uncat_list;
1050			break;
1051		}
1052		if (list) {
1053			struct ubifs_lprops *lprops;
1054			int found = 0;
1055
1056			list_for_each_entry(lprops, list, list) {
1057				if (lprops == lp) {
1058					found = 1;
1059					break;
1060				}
1061			}
1062			if (!found) {
1063				ubifs_err(c, "bad LPT list (category %d)", cat);
1064				return -EINVAL;
1065			}
1066		}
1067	}
1068
1069	/* Check lp is on its category heap (if it has one) */
1070	if (in_tree && cat > 0 && cat <= LPROPS_HEAP_CNT) {
1071		struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
1072
1073		if ((lp->hpos != -1 && heap->arr[lp->hpos]->lnum != lnum) ||
1074		    lp != heap->arr[lp->hpos]) {
1075			ubifs_err(c, "bad LPT heap (category %d)", cat);
1076			return -EINVAL;
1077		}
1078	}
1079
1080	/*
1081	 * After an unclean unmount, empty and freeable LEBs
1082	 * may contain garbage - do not scan them.
1083	 */
1084	if (lp->free == c->leb_size) {
1085		lst->empty_lebs += 1;
1086		lst->total_free += c->leb_size;
1087		lst->total_dark += ubifs_calc_dark(c, c->leb_size);
1088		return LPT_SCAN_CONTINUE;
1089	}
1090	if (lp->free + lp->dirty == c->leb_size &&
1091	    !(lp->flags & LPROPS_INDEX)) {
1092		lst->total_free  += lp->free;
1093		lst->total_dirty += lp->dirty;
1094		lst->total_dark  +=  ubifs_calc_dark(c, c->leb_size);
1095		return LPT_SCAN_CONTINUE;
1096	}
1097
1098	buf = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
1099	if (!buf)
1100		return -ENOMEM;
1101
1102	sleb = ubifs_scan(c, lnum, 0, buf, 0);
1103	if (IS_ERR(sleb)) {
1104		ret = PTR_ERR(sleb);
1105		if (ret == -EUCLEAN) {
1106			ubifs_dump_lprops(c);
1107			ubifs_dump_budg(c, &c->bi);
1108		}
1109		goto out;
1110	}
1111
1112	is_idx = -1;
1113	list_for_each_entry(snod, &sleb->nodes, list) {
1114		int found, level = 0;
1115
1116		cond_resched();
1117
1118		if (is_idx == -1)
1119			is_idx = (snod->type == UBIFS_IDX_NODE) ? 1 : 0;
1120
1121		if (is_idx && snod->type != UBIFS_IDX_NODE) {
1122			ubifs_err(c, "indexing node in data LEB %d:%d",
1123				  lnum, snod->offs);
1124			goto out_destroy;
1125		}
1126
1127		if (snod->type == UBIFS_IDX_NODE) {
1128			struct ubifs_idx_node *idx = snod->node;
1129
1130			key_read(c, ubifs_idx_key(c, idx), &snod->key);
1131			level = le16_to_cpu(idx->level);
1132		}
1133
1134		found = ubifs_tnc_has_node(c, &snod->key, level, lnum,
1135					   snod->offs, is_idx);
1136		if (found) {
1137			if (found < 0)
1138				goto out_destroy;
1139			used += ALIGN(snod->len, 8);
1140		}
1141	}
1142
1143	free = c->leb_size - sleb->endpt;
1144	dirty = sleb->endpt - used;
1145
1146	if (free > c->leb_size || free < 0 || dirty > c->leb_size ||
1147	    dirty < 0) {
1148		ubifs_err(c, "bad calculated accounting for LEB %d: free %d, dirty %d",
1149			  lnum, free, dirty);
1150		goto out_destroy;
1151	}
1152
1153	if (lp->free + lp->dirty == c->leb_size &&
1154	    free + dirty == c->leb_size)
1155		if ((is_idx && !(lp->flags & LPROPS_INDEX)) ||
1156		    (!is_idx && free == c->leb_size) ||
1157		    lp->free == c->leb_size) {
1158			/*
1159			 * Empty or freeable LEBs could contain index
1160			 * nodes from an uncompleted commit due to an
1161			 * unclean unmount. Or they could be empty for
1162			 * the same reason. Or it may simply not have been
1163			 * unmapped.
1164			 */
1165			free = lp->free;
1166			dirty = lp->dirty;
1167			is_idx = 0;
1168		    }
1169
1170	if (is_idx && lp->free + lp->dirty == free + dirty &&
1171	    lnum != c->ihead_lnum) {
1172		/*
1173		 * After an unclean unmount, an index LEB could have a different
1174		 * amount of free space than the value recorded by lprops. That
1175		 * is because the in-the-gaps method may use free space or
1176		 * create free space (as a side-effect of using ubi_leb_change
1177		 * and not writing the whole LEB). The incorrect free space
1178		 * value is not a problem because the index is only ever
1179		 * allocated empty LEBs, so there will never be an attempt to
1180		 * write to the free space at the end of an index LEB - except
1181		 * by the in-the-gaps method for which it is not a problem.
1182		 */
1183		free = lp->free;
1184		dirty = lp->dirty;
1185	}
1186
1187	if (lp->free != free || lp->dirty != dirty)
1188		goto out_print;
1189
1190	if (is_idx && !(lp->flags & LPROPS_INDEX)) {
1191		if (free == c->leb_size)
1192			/* Free but not unmapped LEB, it's fine */
1193			is_idx = 0;
1194		else {
1195			ubifs_err(c, "indexing node without indexing flag");
1196			goto out_print;
1197		}
1198	}
1199
1200	if (!is_idx && (lp->flags & LPROPS_INDEX)) {
1201		ubifs_err(c, "data node with indexing flag");
1202		goto out_print;
1203	}
1204
1205	if (free == c->leb_size)
1206		lst->empty_lebs += 1;
1207
1208	if (is_idx)
1209		lst->idx_lebs += 1;
1210
1211	if (!(lp->flags & LPROPS_INDEX))
1212		lst->total_used += c->leb_size - free - dirty;
1213	lst->total_free += free;
1214	lst->total_dirty += dirty;
1215
1216	if (!(lp->flags & LPROPS_INDEX)) {
1217		int spc = free + dirty;
1218
1219		if (spc < c->dead_wm)
1220			lst->total_dead += spc;
1221		else
1222			lst->total_dark += ubifs_calc_dark(c, spc);
1223	}
1224
1225	ubifs_scan_destroy(sleb);
1226	vfree(buf);
1227	return LPT_SCAN_CONTINUE;
1228
1229out_print:
1230	ubifs_err(c, "bad accounting of LEB %d: free %d, dirty %d flags %#x, should be free %d, dirty %d",
1231		  lnum, lp->free, lp->dirty, lp->flags, free, dirty);
1232	ubifs_dump_leb(c, lnum);
1233out_destroy:
1234	ubifs_scan_destroy(sleb);
1235	ret = -EINVAL;
1236out:
1237	vfree(buf);
1238	return ret;
1239}
1240
1241/**
1242 * dbg_check_lprops - check all LEB properties.
1243 * @c: UBIFS file-system description object
1244 *
1245 * This function checks all LEB properties and makes sure they are all correct.
1246 * It returns zero if everything is fine, %-EINVAL if there is an inconsistency
1247 * and other negative error codes in case of other errors. This function is
1248 * called while the file system is locked (because of commit start), so no
1249 * additional locking is required. Note that locking the LPT mutex would cause
1250 * a circular lock dependency with the TNC mutex.
1251 */
1252int dbg_check_lprops(struct ubifs_info *c)
1253{
1254	int i, err;
1255	struct ubifs_lp_stats lst;
1256
1257	if (!dbg_is_chk_lprops(c))
1258		return 0;
1259
1260	/*
1261	 * As we are going to scan the media, the write buffers have to be
1262	 * synchronized.
1263	 */
1264	for (i = 0; i < c->jhead_cnt; i++) {
1265		err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
1266		if (err)
1267			return err;
1268	}
1269
1270	memset(&lst, 0, sizeof(struct ubifs_lp_stats));
1271	err = ubifs_lpt_scan_nolock(c, c->main_first, c->leb_cnt - 1,
1272				    (ubifs_lpt_scan_callback)scan_check_cb,
1273				    &lst);
1274	if (err && err != -ENOSPC)
1275		goto out;
1276
1277	if (lst.empty_lebs != c->lst.empty_lebs ||
1278	    lst.idx_lebs != c->lst.idx_lebs ||
1279	    lst.total_free != c->lst.total_free ||
1280	    lst.total_dirty != c->lst.total_dirty ||
1281	    lst.total_used != c->lst.total_used) {
1282		ubifs_err(c, "bad overall accounting");
1283		ubifs_err(c, "calculated: empty_lebs %d, idx_lebs %d, total_free %lld, total_dirty %lld, total_used %lld",
1284			  lst.empty_lebs, lst.idx_lebs, lst.total_free,
1285			  lst.total_dirty, lst.total_used);
1286		ubifs_err(c, "read from lprops: empty_lebs %d, idx_lebs %d, total_free %lld, total_dirty %lld, total_used %lld",
1287			  c->lst.empty_lebs, c->lst.idx_lebs, c->lst.total_free,
1288			  c->lst.total_dirty, c->lst.total_used);
1289		err = -EINVAL;
1290		goto out;
1291	}
1292
1293	if (lst.total_dead != c->lst.total_dead ||
1294	    lst.total_dark != c->lst.total_dark) {
1295		ubifs_err(c, "bad dead/dark space accounting");
1296		ubifs_err(c, "calculated: total_dead %lld, total_dark %lld",
1297			  lst.total_dead, lst.total_dark);
1298		ubifs_err(c, "read from lprops: total_dead %lld, total_dark %lld",
1299			  c->lst.total_dead, c->lst.total_dark);
1300		err = -EINVAL;
1301		goto out;
1302	}
1303
1304	err = dbg_check_cats(c);
1305out:
1306	return err;
1307}