linux/fs/ubifs/lprops.c
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   1/*
   2 * This file is part of UBIFS.
   3 *
   4 * Copyright (C) 2006-2008 Nokia Corporation.
   5 *
   6 * This program is free software; you can redistribute it and/or modify it
   7 * under the terms of the GNU General Public License version 2 as published by
   8 * the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope that it will be useful, but WITHOUT
  11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13 * more details.
  14 *
  15 * You should have received a copy of the GNU General Public License along with
  16 * this program; if not, write to the Free Software Foundation, Inc., 51
  17 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  18 *
  19 * Authors: Adrian Hunter
  20 *          Artem Bityutskiy (Битюцкий Артём)
  21 */
  22
  23/*
  24 * This file implements the functions that access LEB properties and their
  25 * categories. LEBs are categorized based on the needs of UBIFS, and the
  26 * categories are stored as either heaps or lists to provide a fast way of
  27 * finding a LEB in a particular category. For example, UBIFS may need to find
  28 * an empty LEB for the journal, or a very dirty LEB for garbage collection.
  29 */
  30
  31#include "ubifs.h"
  32
  33/**
  34 * get_heap_comp_val - get the LEB properties value for heap comparisons.
  35 * @lprops: LEB properties
  36 * @cat: LEB category
  37 */
  38static int get_heap_comp_val(struct ubifs_lprops *lprops, int cat)
  39{
  40        switch (cat) {
  41        case LPROPS_FREE:
  42                return lprops->free;
  43        case LPROPS_DIRTY_IDX:
  44                return lprops->free + lprops->dirty;
  45        default:
  46                return lprops->dirty;
  47        }
  48}
  49
  50/**
  51 * move_up_lpt_heap - move a new heap entry up as far as possible.
  52 * @c: UBIFS file-system description object
  53 * @heap: LEB category heap
  54 * @lprops: LEB properties to move
  55 * @cat: LEB category
  56 *
  57 * New entries to a heap are added at the bottom and then moved up until the
  58 * parent's value is greater.  In the case of LPT's category heaps, the value
  59 * is either the amount of free space or the amount of dirty space, depending
  60 * on the category.
  61 */
  62static void move_up_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
  63                             struct ubifs_lprops *lprops, int cat)
  64{
  65        int val1, val2, hpos;
  66
  67        hpos = lprops->hpos;
  68        if (!hpos)
  69                return; /* Already top of the heap */
  70        val1 = get_heap_comp_val(lprops, cat);
  71        /* Compare to parent and, if greater, move up the heap */
  72        do {
  73                int ppos = (hpos - 1) / 2;
  74
  75                val2 = get_heap_comp_val(heap->arr[ppos], cat);
  76                if (val2 >= val1)
  77                        return;
  78                /* Greater than parent so move up */
  79                heap->arr[ppos]->hpos = hpos;
  80                heap->arr[hpos] = heap->arr[ppos];
  81                heap->arr[ppos] = lprops;
  82                lprops->hpos = ppos;
  83                hpos = ppos;
  84        } while (hpos);
  85}
  86
  87/**
  88 * adjust_lpt_heap - move a changed heap entry up or down the heap.
  89 * @c: UBIFS file-system description object
  90 * @heap: LEB category heap
  91 * @lprops: LEB properties to move
  92 * @hpos: heap position of @lprops
  93 * @cat: LEB category
  94 *
  95 * Changed entries in a heap are moved up or down until the parent's value is
  96 * greater.  In the case of LPT's category heaps, the value is either the amount
  97 * of free space or the amount of dirty space, depending on the category.
  98 */
  99static void adjust_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
 100                            struct ubifs_lprops *lprops, int hpos, int cat)
 101{
 102        int val1, val2, val3, cpos;
 103
 104        val1 = get_heap_comp_val(lprops, cat);
 105        /* Compare to parent and, if greater than parent, move up the heap */
 106        if (hpos) {
 107                int ppos = (hpos - 1) / 2;
 108
 109                val2 = get_heap_comp_val(heap->arr[ppos], cat);
 110                if (val1 > val2) {
 111                        /* Greater than parent so move up */
 112                        while (1) {
 113                                heap->arr[ppos]->hpos = hpos;
 114                                heap->arr[hpos] = heap->arr[ppos];
 115                                heap->arr[ppos] = lprops;
 116                                lprops->hpos = ppos;
 117                                hpos = ppos;
 118                                if (!hpos)
 119                                        return;
 120                                ppos = (hpos - 1) / 2;
 121                                val2 = get_heap_comp_val(heap->arr[ppos], cat);
 122                                if (val1 <= val2)
 123                                        return;
 124                                /* Still greater than parent so keep going */
 125                        }
 126                }
 127        }
 128
 129        /* Not greater than parent, so compare to children */
 130        while (1) {
 131                /* Compare to left child */
 132                cpos = hpos * 2 + 1;
 133                if (cpos >= heap->cnt)
 134                        return;
 135                val2 = get_heap_comp_val(heap->arr[cpos], cat);
 136                if (val1 < val2) {
 137                        /* Less than left child, so promote biggest child */
 138                        if (cpos + 1 < heap->cnt) {
 139                                val3 = get_heap_comp_val(heap->arr[cpos + 1],
 140                                                         cat);
 141                                if (val3 > val2)
 142                                        cpos += 1; /* Right child is bigger */
 143                        }
 144                        heap->arr[cpos]->hpos = hpos;
 145                        heap->arr[hpos] = heap->arr[cpos];
 146                        heap->arr[cpos] = lprops;
 147                        lprops->hpos = cpos;
 148                        hpos = cpos;
 149                        continue;
 150                }
 151                /* Compare to right child */
 152                cpos += 1;
 153                if (cpos >= heap->cnt)
 154                        return;
 155                val3 = get_heap_comp_val(heap->arr[cpos], cat);
 156                if (val1 < val3) {
 157                        /* Less than right child, so promote right child */
 158                        heap->arr[cpos]->hpos = hpos;
 159                        heap->arr[hpos] = heap->arr[cpos];
 160                        heap->arr[cpos] = lprops;
 161                        lprops->hpos = cpos;
 162                        hpos = cpos;
 163                        continue;
 164                }
 165                return;
 166        }
 167}
 168
 169/**
 170 * add_to_lpt_heap - add LEB properties to a LEB category heap.
 171 * @c: UBIFS file-system description object
 172 * @lprops: LEB properties to add
 173 * @cat: LEB category
 174 *
 175 * This function returns %1 if @lprops is added to the heap for LEB category
 176 * @cat, otherwise %0 is returned because the heap is full.
 177 */
 178static int add_to_lpt_heap(struct ubifs_info *c, struct ubifs_lprops *lprops,
 179                           int cat)
 180{
 181        struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
 182
 183        if (heap->cnt >= heap->max_cnt) {
 184                const int b = LPT_HEAP_SZ / 2 - 1;
 185                int cpos, val1, val2;
 186
 187                /* Compare to some other LEB on the bottom of heap */
 188                /* Pick a position kind of randomly */
 189                cpos = (((size_t)lprops >> 4) & b) + b;
 190                ubifs_assert(cpos >= b);
 191                ubifs_assert(cpos < LPT_HEAP_SZ);
 192                ubifs_assert(cpos < heap->cnt);
 193
 194                val1 = get_heap_comp_val(lprops, cat);
 195                val2 = get_heap_comp_val(heap->arr[cpos], cat);
 196                if (val1 > val2) {
 197                        struct ubifs_lprops *lp;
 198
 199                        lp = heap->arr[cpos];
 200                        lp->flags &= ~LPROPS_CAT_MASK;
 201                        lp->flags |= LPROPS_UNCAT;
 202                        list_add(&lp->list, &c->uncat_list);
 203                        lprops->hpos = cpos;
 204                        heap->arr[cpos] = lprops;
 205                        move_up_lpt_heap(c, heap, lprops, cat);
 206                        dbg_check_heap(c, heap, cat, lprops->hpos);
 207                        return 1; /* Added to heap */
 208                }
 209                dbg_check_heap(c, heap, cat, -1);
 210                return 0; /* Not added to heap */
 211        } else {
 212                lprops->hpos = heap->cnt++;
 213                heap->arr[lprops->hpos] = lprops;
 214                move_up_lpt_heap(c, heap, lprops, cat);
 215                dbg_check_heap(c, heap, cat, lprops->hpos);
 216                return 1; /* Added to heap */
 217        }
 218}
 219
 220/**
 221 * remove_from_lpt_heap - remove LEB properties from a LEB category heap.
 222 * @c: UBIFS file-system description object
 223 * @lprops: LEB properties to remove
 224 * @cat: LEB category
 225 */
 226static void remove_from_lpt_heap(struct ubifs_info *c,
 227                                 struct ubifs_lprops *lprops, int cat)
 228{
 229        struct ubifs_lpt_heap *heap;
 230        int hpos = lprops->hpos;
 231
 232        heap = &c->lpt_heap[cat - 1];
 233        ubifs_assert(hpos >= 0 && hpos < heap->cnt);
 234        ubifs_assert(heap->arr[hpos] == lprops);
 235        heap->cnt -= 1;
 236        if (hpos < heap->cnt) {
 237                heap->arr[hpos] = heap->arr[heap->cnt];
 238                heap->arr[hpos]->hpos = hpos;
 239                adjust_lpt_heap(c, heap, heap->arr[hpos], hpos, cat);
 240        }
 241        dbg_check_heap(c, heap, cat, -1);
 242}
 243
 244/**
 245 * lpt_heap_replace - replace lprops in a category heap.
 246 * @c: UBIFS file-system description object
 247 * @old_lprops: LEB properties to replace
 248 * @new_lprops: LEB properties with which to replace
 249 * @cat: LEB category
 250 *
 251 * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
 252 * and the lprops that the pnode contains.  When that happens, references in
 253 * the category heaps to those lprops must be updated to point to the new
 254 * lprops.  This function does that.
 255 */
 256static void lpt_heap_replace(struct ubifs_info *c,
 257                             struct ubifs_lprops *old_lprops,
 258                             struct ubifs_lprops *new_lprops, int cat)
 259{
 260        struct ubifs_lpt_heap *heap;
 261        int hpos = new_lprops->hpos;
 262
 263        heap = &c->lpt_heap[cat - 1];
 264        heap->arr[hpos] = new_lprops;
 265}
 266
 267/**
 268 * ubifs_add_to_cat - add LEB properties to a category list or heap.
 269 * @c: UBIFS file-system description object
 270 * @lprops: LEB properties to add
 271 * @cat: LEB category to which to add
 272 *
 273 * LEB properties are categorized to enable fast find operations.
 274 */
 275void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
 276                      int cat)
 277{
 278        switch (cat) {
 279        case LPROPS_DIRTY:
 280        case LPROPS_DIRTY_IDX:
 281        case LPROPS_FREE:
 282                if (add_to_lpt_heap(c, lprops, cat))
 283                        break;
 284                /* No more room on heap so make it un-categorized */
 285                cat = LPROPS_UNCAT;
 286                /* Fall through */
 287        case LPROPS_UNCAT:
 288                list_add(&lprops->list, &c->uncat_list);
 289                break;
 290        case LPROPS_EMPTY:
 291                list_add(&lprops->list, &c->empty_list);
 292                break;
 293        case LPROPS_FREEABLE:
 294                list_add(&lprops->list, &c->freeable_list);
 295                c->freeable_cnt += 1;
 296                break;
 297        case LPROPS_FRDI_IDX:
 298                list_add(&lprops->list, &c->frdi_idx_list);
 299                break;
 300        default:
 301                ubifs_assert(0);
 302        }
 303        lprops->flags &= ~LPROPS_CAT_MASK;
 304        lprops->flags |= cat;
 305}
 306
 307/**
 308 * ubifs_remove_from_cat - remove LEB properties from a category list or heap.
 309 * @c: UBIFS file-system description object
 310 * @lprops: LEB properties to remove
 311 * @cat: LEB category from which to remove
 312 *
 313 * LEB properties are categorized to enable fast find operations.
 314 */
 315static void ubifs_remove_from_cat(struct ubifs_info *c,
 316                                  struct ubifs_lprops *lprops, int cat)
 317{
 318        switch (cat) {
 319        case LPROPS_DIRTY:
 320        case LPROPS_DIRTY_IDX:
 321        case LPROPS_FREE:
 322                remove_from_lpt_heap(c, lprops, cat);
 323                break;
 324        case LPROPS_FREEABLE:
 325                c->freeable_cnt -= 1;
 326                ubifs_assert(c->freeable_cnt >= 0);
 327                /* Fall through */
 328        case LPROPS_UNCAT:
 329        case LPROPS_EMPTY:
 330        case LPROPS_FRDI_IDX:
 331                ubifs_assert(!list_empty(&lprops->list));
 332                list_del(&lprops->list);
 333                break;
 334        default:
 335                ubifs_assert(0);
 336        }
 337}
 338
 339/**
 340 * ubifs_replace_cat - replace lprops in a category list or heap.
 341 * @c: UBIFS file-system description object
 342 * @old_lprops: LEB properties to replace
 343 * @new_lprops: LEB properties with which to replace
 344 *
 345 * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
 346 * and the lprops that the pnode contains. When that happens, references in
 347 * category lists and heaps must be replaced. This function does that.
 348 */
 349void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
 350                       struct ubifs_lprops *new_lprops)
 351{
 352        int cat;
 353
 354        cat = new_lprops->flags & LPROPS_CAT_MASK;
 355        switch (cat) {
 356        case LPROPS_DIRTY:
 357        case LPROPS_DIRTY_IDX:
 358        case LPROPS_FREE:
 359                lpt_heap_replace(c, old_lprops, new_lprops, cat);
 360                break;
 361        case LPROPS_UNCAT:
 362        case LPROPS_EMPTY:
 363        case LPROPS_FREEABLE:
 364        case LPROPS_FRDI_IDX:
 365                list_replace(&old_lprops->list, &new_lprops->list);
 366                break;
 367        default:
 368                ubifs_assert(0);
 369        }
 370}
 371
 372/**
 373 * ubifs_ensure_cat - ensure LEB properties are categorized.
 374 * @c: UBIFS file-system description object
 375 * @lprops: LEB properties
 376 *
 377 * A LEB may have fallen off of the bottom of a heap, and ended up as
 378 * un-categorized even though it has enough space for us now. If that is the
 379 * case this function will put the LEB back onto a heap.
 380 */
 381void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops)
 382{
 383        int cat = lprops->flags & LPROPS_CAT_MASK;
 384
 385        if (cat != LPROPS_UNCAT)
 386                return;
 387        cat = ubifs_categorize_lprops(c, lprops);
 388        if (cat == LPROPS_UNCAT)
 389                return;
 390        ubifs_remove_from_cat(c, lprops, LPROPS_UNCAT);
 391        ubifs_add_to_cat(c, lprops, cat);
 392}
 393
 394/**
 395 * ubifs_categorize_lprops - categorize LEB properties.
 396 * @c: UBIFS file-system description object
 397 * @lprops: LEB properties to categorize
 398 *
 399 * LEB properties are categorized to enable fast find operations. This function
 400 * returns the LEB category to which the LEB properties belong. Note however
 401 * that if the LEB category is stored as a heap and the heap is full, the
 402 * LEB properties may have their category changed to %LPROPS_UNCAT.
 403 */
 404int ubifs_categorize_lprops(const struct ubifs_info *c,
 405                            const struct ubifs_lprops *lprops)
 406{
 407        if (lprops->flags & LPROPS_TAKEN)
 408                return LPROPS_UNCAT;
 409
 410        if (lprops->free == c->leb_size) {
 411                ubifs_assert(!(lprops->flags & LPROPS_INDEX));
 412                return LPROPS_EMPTY;
 413        }
 414
 415        if (lprops->free + lprops->dirty == c->leb_size) {
 416                if (lprops->flags & LPROPS_INDEX)
 417                        return LPROPS_FRDI_IDX;
 418                else
 419                        return LPROPS_FREEABLE;
 420        }
 421
 422        if (lprops->flags & LPROPS_INDEX) {
 423                if (lprops->dirty + lprops->free >= c->min_idx_node_sz)
 424                        return LPROPS_DIRTY_IDX;
 425        } else {
 426                if (lprops->dirty >= c->dead_wm &&
 427                    lprops->dirty > lprops->free)
 428                        return LPROPS_DIRTY;
 429                if (lprops->free > 0)
 430                        return LPROPS_FREE;
 431        }
 432
 433        return LPROPS_UNCAT;
 434}
 435
 436/**
 437 * change_category - change LEB properties category.
 438 * @c: UBIFS file-system description object
 439 * @lprops: LEB properties to re-categorize
 440 *
 441 * LEB properties are categorized to enable fast find operations. When the LEB
 442 * properties change they must be re-categorized.
 443 */
 444static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops)
 445{
 446        int old_cat = lprops->flags & LPROPS_CAT_MASK;
 447        int new_cat = ubifs_categorize_lprops(c, lprops);
 448
 449        if (old_cat == new_cat) {
 450                struct ubifs_lpt_heap *heap = &c->lpt_heap[new_cat - 1];
 451
 452                /* lprops on a heap now must be moved up or down */
 453                if (new_cat < 1 || new_cat > LPROPS_HEAP_CNT)
 454                        return; /* Not on a heap */
 455                heap = &c->lpt_heap[new_cat - 1];
 456                adjust_lpt_heap(c, heap, lprops, lprops->hpos, new_cat);
 457        } else {
 458                ubifs_remove_from_cat(c, lprops, old_cat);
 459                ubifs_add_to_cat(c, lprops, new_cat);
 460        }
 461}
 462
 463/**
 464 * ubifs_calc_dark - calculate LEB dark space size.
 465 * @c: the UBIFS file-system description object
 466 * @spc: amount of free and dirty space in the LEB
 467 *
 468 * This function calculates and returns amount of dark space in an LEB which
 469 * has @spc bytes of free and dirty space.
 470 *
 471 * UBIFS is trying to account the space which might not be usable, and this
 472 * space is called "dark space". For example, if an LEB has only %512 free
 473 * bytes, it is dark space, because it cannot fit a large data node.
 474 */
 475int ubifs_calc_dark(const struct ubifs_info *c, int spc)
 476{
 477        ubifs_assert(!(spc & 7));
 478
 479        if (spc < c->dark_wm)
 480                return spc;
 481
 482        /*
 483         * If we have slightly more space then the dark space watermark, we can
 484         * anyway safely assume it we'll be able to write a node of the
 485         * smallest size there.
 486         */
 487        if (spc - c->dark_wm < MIN_WRITE_SZ)
 488                return spc - MIN_WRITE_SZ;
 489
 490        return c->dark_wm;
 491}
 492
 493/**
 494 * is_lprops_dirty - determine if LEB properties are dirty.
 495 * @c: the UBIFS file-system description object
 496 * @lprops: LEB properties to test
 497 */
 498static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops)
 499{
 500        struct ubifs_pnode *pnode;
 501        int pos;
 502
 503        pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1);
 504        pnode = (struct ubifs_pnode *)container_of(lprops - pos,
 505                                                   struct ubifs_pnode,
 506                                                   lprops[0]);
 507        return !test_bit(COW_CNODE, &pnode->flags) &&
 508               test_bit(DIRTY_CNODE, &pnode->flags);
 509}
 510
 511/**
 512 * ubifs_change_lp - change LEB properties.
 513 * @c: the UBIFS file-system description object
 514 * @lp: LEB properties to change
 515 * @free: new free space amount
 516 * @dirty: new dirty space amount
 517 * @flags: new flags
 518 * @idx_gc_cnt: change to the count of @idx_gc list
 519 *
 520 * This function changes LEB properties (@free, @dirty or @flag). However, the
 521 * property which has the %LPROPS_NC value is not changed. Returns a pointer to
 522 * the updated LEB properties on success and a negative error code on failure.
 523 *
 524 * Note, the LEB properties may have had to be copied (due to COW) and
 525 * consequently the pointer returned may not be the same as the pointer
 526 * passed.
 527 */
 528const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
 529                                           const struct ubifs_lprops *lp,
 530                                           int free, int dirty, int flags,
 531                                           int idx_gc_cnt)
 532{
 533        /*
 534         * This is the only function that is allowed to change lprops, so we
 535         * discard the "const" qualifier.
 536         */
 537        struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp;
 538
 539        dbg_lp("LEB %d, free %d, dirty %d, flags %d",
 540               lprops->lnum, free, dirty, flags);
 541
 542        ubifs_assert(mutex_is_locked(&c->lp_mutex));
 543        ubifs_assert(c->lst.empty_lebs >= 0 &&
 544                     c->lst.empty_lebs <= c->main_lebs);
 545        ubifs_assert(c->freeable_cnt >= 0);
 546        ubifs_assert(c->freeable_cnt <= c->main_lebs);
 547        ubifs_assert(c->lst.taken_empty_lebs >= 0);
 548        ubifs_assert(c->lst.taken_empty_lebs <= c->lst.empty_lebs);
 549        ubifs_assert(!(c->lst.total_free & 7) && !(c->lst.total_dirty & 7));
 550        ubifs_assert(!(c->lst.total_dead & 7) && !(c->lst.total_dark & 7));
 551        ubifs_assert(!(c->lst.total_used & 7));
 552        ubifs_assert(free == LPROPS_NC || free >= 0);
 553        ubifs_assert(dirty == LPROPS_NC || dirty >= 0);
 554
 555        if (!is_lprops_dirty(c, lprops)) {
 556                lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum);
 557                if (IS_ERR(lprops))
 558                        return lprops;
 559        } else
 560                ubifs_assert(lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum));
 561
 562        ubifs_assert(!(lprops->free & 7) && !(lprops->dirty & 7));
 563
 564        spin_lock(&c->space_lock);
 565        if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
 566                c->lst.taken_empty_lebs -= 1;
 567
 568        if (!(lprops->flags & LPROPS_INDEX)) {
 569                int old_spc;
 570
 571                old_spc = lprops->free + lprops->dirty;
 572                if (old_spc < c->dead_wm)
 573                        c->lst.total_dead -= old_spc;
 574                else
 575                        c->lst.total_dark -= ubifs_calc_dark(c, old_spc);
 576
 577                c->lst.total_used -= c->leb_size - old_spc;
 578        }
 579
 580        if (free != LPROPS_NC) {
 581                free = ALIGN(free, 8);
 582                c->lst.total_free += free - lprops->free;
 583
 584                /* Increase or decrease empty LEBs counter if needed */
 585                if (free == c->leb_size) {
 586                        if (lprops->free != c->leb_size)
 587                                c->lst.empty_lebs += 1;
 588                } else if (lprops->free == c->leb_size)
 589                        c->lst.empty_lebs -= 1;
 590                lprops->free = free;
 591        }
 592
 593        if (dirty != LPROPS_NC) {
 594                dirty = ALIGN(dirty, 8);
 595                c->lst.total_dirty += dirty - lprops->dirty;
 596                lprops->dirty = dirty;
 597        }
 598
 599        if (flags != LPROPS_NC) {
 600                /* Take care about indexing LEBs counter if needed */
 601                if ((lprops->flags & LPROPS_INDEX)) {
 602                        if (!(flags & LPROPS_INDEX))
 603                                c->lst.idx_lebs -= 1;
 604                } else if (flags & LPROPS_INDEX)
 605                        c->lst.idx_lebs += 1;
 606                lprops->flags = flags;
 607        }
 608
 609        if (!(lprops->flags & LPROPS_INDEX)) {
 610                int new_spc;
 611
 612                new_spc = lprops->free + lprops->dirty;
 613                if (new_spc < c->dead_wm)
 614                        c->lst.total_dead += new_spc;
 615                else
 616                        c->lst.total_dark += ubifs_calc_dark(c, new_spc);
 617
 618                c->lst.total_used += c->leb_size - new_spc;
 619        }
 620
 621        if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
 622                c->lst.taken_empty_lebs += 1;
 623
 624        change_category(c, lprops);
 625        c->idx_gc_cnt += idx_gc_cnt;
 626        spin_unlock(&c->space_lock);
 627        return lprops;
 628}
 629
 630/**
 631 * ubifs_get_lp_stats - get lprops statistics.
 632 * @c: UBIFS file-system description object
 633 * @st: return statistics
 634 */
 635void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst)
 636{
 637        spin_lock(&c->space_lock);
 638        memcpy(lst, &c->lst, sizeof(struct ubifs_lp_stats));
 639        spin_unlock(&c->space_lock);
 640}
 641
 642/**
 643 * ubifs_change_one_lp - change LEB properties.
 644 * @c: the UBIFS file-system description object
 645 * @lnum: LEB to change properties for
 646 * @free: amount of free space
 647 * @dirty: amount of dirty space
 648 * @flags_set: flags to set
 649 * @flags_clean: flags to clean
 650 * @idx_gc_cnt: change to the count of idx_gc list
 651 *
 652 * This function changes properties of LEB @lnum. It is a helper wrapper over
 653 * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the
 654 * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and
 655 * a negative error code in case of failure.
 656 */
 657int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
 658                        int flags_set, int flags_clean, int idx_gc_cnt)
 659{
 660        int err = 0, flags;
 661        const struct ubifs_lprops *lp;
 662
 663        ubifs_get_lprops(c);
 664
 665        lp = ubifs_lpt_lookup_dirty(c, lnum);
 666        if (IS_ERR(lp)) {
 667                err = PTR_ERR(lp);
 668                goto out;
 669        }
 670
 671        flags = (lp->flags | flags_set) & ~flags_clean;
 672        lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt);
 673        if (IS_ERR(lp))
 674                err = PTR_ERR(lp);
 675
 676out:
 677        ubifs_release_lprops(c);
 678        if (err)
 679                ubifs_err("cannot change properties of LEB %d, error %d",
 680                          lnum, err);
 681        return err;
 682}
 683
 684/**
 685 * ubifs_update_one_lp - update LEB properties.
 686 * @c: the UBIFS file-system description object
 687 * @lnum: LEB to change properties for
 688 * @free: amount of free space
 689 * @dirty: amount of dirty space to add
 690 * @flags_set: flags to set
 691 * @flags_clean: flags to clean
 692 *
 693 * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to
 694 * current dirty space, not substitutes it.
 695 */
 696int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
 697                        int flags_set, int flags_clean)
 698{
 699        int err = 0, flags;
 700        const struct ubifs_lprops *lp;
 701
 702        ubifs_get_lprops(c);
 703
 704        lp = ubifs_lpt_lookup_dirty(c, lnum);
 705        if (IS_ERR(lp)) {
 706                err = PTR_ERR(lp);
 707                goto out;
 708        }
 709
 710        flags = (lp->flags | flags_set) & ~flags_clean;
 711        lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0);
 712        if (IS_ERR(lp))
 713                err = PTR_ERR(lp);
 714
 715out:
 716        ubifs_release_lprops(c);
 717        if (err)
 718                ubifs_err("cannot update properties of LEB %d, error %d",
 719                          lnum, err);
 720        return err;
 721}
 722
 723/**
 724 * ubifs_read_one_lp - read LEB properties.
 725 * @c: the UBIFS file-system description object
 726 * @lnum: LEB to read properties for
 727 * @lp: where to store read properties
 728 *
 729 * This helper function reads properties of a LEB @lnum and stores them in @lp.
 730 * Returns zero in case of success and a negative error code in case of
 731 * failure.
 732 */
 733int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp)
 734{
 735        int err = 0;
 736        const struct ubifs_lprops *lpp;
 737
 738        ubifs_get_lprops(c);
 739
 740        lpp = ubifs_lpt_lookup(c, lnum);
 741        if (IS_ERR(lpp)) {
 742                err = PTR_ERR(lpp);
 743                ubifs_err("cannot read properties of LEB %d, error %d",
 744                          lnum, err);
 745                goto out;
 746        }
 747
 748        memcpy(lp, lpp, sizeof(struct ubifs_lprops));
 749
 750out:
 751        ubifs_release_lprops(c);
 752        return err;
 753}
 754
 755/**
 756 * ubifs_fast_find_free - try to find a LEB with free space quickly.
 757 * @c: the UBIFS file-system description object
 758 *
 759 * This function returns LEB properties for a LEB with free space or %NULL if
 760 * the function is unable to find a LEB quickly.
 761 */
 762const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c)
 763{
 764        struct ubifs_lprops *lprops;
 765        struct ubifs_lpt_heap *heap;
 766
 767        ubifs_assert(mutex_is_locked(&c->lp_mutex));
 768
 769        heap = &c->lpt_heap[LPROPS_FREE - 1];
 770        if (heap->cnt == 0)
 771                return NULL;
 772
 773        lprops = heap->arr[0];
 774        ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
 775        ubifs_assert(!(lprops->flags & LPROPS_INDEX));
 776        return lprops;
 777}
 778
 779/**
 780 * ubifs_fast_find_empty - try to find an empty LEB quickly.
 781 * @c: the UBIFS file-system description object
 782 *
 783 * This function returns LEB properties for an empty LEB or %NULL if the
 784 * function is unable to find an empty LEB quickly.
 785 */
 786const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c)
 787{
 788        struct ubifs_lprops *lprops;
 789
 790        ubifs_assert(mutex_is_locked(&c->lp_mutex));
 791
 792        if (list_empty(&c->empty_list))
 793                return NULL;
 794
 795        lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list);
 796        ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
 797        ubifs_assert(!(lprops->flags & LPROPS_INDEX));
 798        ubifs_assert(lprops->free == c->leb_size);
 799        return lprops;
 800}
 801
 802/**
 803 * ubifs_fast_find_freeable - try to find a freeable LEB quickly.
 804 * @c: the UBIFS file-system description object
 805 *
 806 * This function returns LEB properties for a freeable LEB or %NULL if the
 807 * function is unable to find a freeable LEB quickly.
 808 */
 809const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c)
 810{
 811        struct ubifs_lprops *lprops;
 812
 813        ubifs_assert(mutex_is_locked(&c->lp_mutex));
 814
 815        if (list_empty(&c->freeable_list))
 816                return NULL;
 817
 818        lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list);
 819        ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
 820        ubifs_assert(!(lprops->flags & LPROPS_INDEX));
 821        ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
 822        ubifs_assert(c->freeable_cnt > 0);
 823        return lprops;
 824}
 825
 826/**
 827 * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly.
 828 * @c: the UBIFS file-system description object
 829 *
 830 * This function returns LEB properties for a freeable index LEB or %NULL if the
 831 * function is unable to find a freeable index LEB quickly.
 832 */
 833const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c)
 834{
 835        struct ubifs_lprops *lprops;
 836
 837        ubifs_assert(mutex_is_locked(&c->lp_mutex));
 838
 839        if (list_empty(&c->frdi_idx_list))
 840                return NULL;
 841
 842        lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list);
 843        ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
 844        ubifs_assert((lprops->flags & LPROPS_INDEX));
 845        ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
 846        return lprops;
 847}
 848
 849#ifdef CONFIG_UBIFS_FS_DEBUG
 850
 851/**
 852 * dbg_check_cats - check category heaps and lists.
 853 * @c: UBIFS file-system description object
 854 *
 855 * This function returns %0 on success and a negative error code on failure.
 856 */
 857int dbg_check_cats(struct ubifs_info *c)
 858{
 859        struct ubifs_lprops *lprops;
 860        struct list_head *pos;
 861        int i, cat;
 862
 863        if (!dbg_is_chk_gen(c) && !dbg_is_chk_lprops(c))
 864                return 0;
 865
 866        list_for_each_entry(lprops, &c->empty_list, list) {
 867                if (lprops->free != c->leb_size) {
 868                        ubifs_err("non-empty LEB %d on empty list "
 869                                  "(free %d dirty %d flags %d)", lprops->lnum,
 870                                  lprops->free, lprops->dirty, lprops->flags);
 871                        return -EINVAL;
 872                }
 873                if (lprops->flags & LPROPS_TAKEN) {
 874                        ubifs_err("taken LEB %d on empty list "
 875                                  "(free %d dirty %d flags %d)", lprops->lnum,
 876                                  lprops->free, lprops->dirty, lprops->flags);
 877                        return -EINVAL;
 878                }
 879        }
 880
 881        i = 0;
 882        list_for_each_entry(lprops, &c->freeable_list, list) {
 883                if (lprops->free + lprops->dirty != c->leb_size) {
 884                        ubifs_err("non-freeable LEB %d on freeable list "
 885                                  "(free %d dirty %d flags %d)", lprops->lnum,
 886                                  lprops->free, lprops->dirty, lprops->flags);
 887                        return -EINVAL;
 888                }
 889                if (lprops->flags & LPROPS_TAKEN) {
 890                        ubifs_err("taken LEB %d on freeable list "
 891                                  "(free %d dirty %d flags %d)", lprops->lnum,
 892                                  lprops->free, lprops->dirty, lprops->flags);
 893                        return -EINVAL;
 894                }
 895                i += 1;
 896        }
 897        if (i != c->freeable_cnt) {
 898                ubifs_err("freeable list count %d expected %d", i,
 899                          c->freeable_cnt);
 900                return -EINVAL;
 901        }
 902
 903        i = 0;
 904        list_for_each(pos, &c->idx_gc)
 905                i += 1;
 906        if (i != c->idx_gc_cnt) {
 907                ubifs_err("idx_gc list count %d expected %d", i,
 908                          c->idx_gc_cnt);
 909                return -EINVAL;
 910        }
 911
 912        list_for_each_entry(lprops, &c->frdi_idx_list, list) {
 913                if (lprops->free + lprops->dirty != c->leb_size) {
 914                        ubifs_err("non-freeable LEB %d on frdi_idx list "
 915                                  "(free %d dirty %d flags %d)", lprops->lnum,
 916                                  lprops->free, lprops->dirty, lprops->flags);
 917                        return -EINVAL;
 918                }
 919                if (lprops->flags & LPROPS_TAKEN) {
 920                        ubifs_err("taken LEB %d on frdi_idx list "
 921                                  "(free %d dirty %d flags %d)", lprops->lnum,
 922                                  lprops->free, lprops->dirty, lprops->flags);
 923                        return -EINVAL;
 924                }
 925                if (!(lprops->flags & LPROPS_INDEX)) {
 926                        ubifs_err("non-index LEB %d on frdi_idx list "
 927                                  "(free %d dirty %d flags %d)", lprops->lnum,
 928                                  lprops->free, lprops->dirty, lprops->flags);
 929                        return -EINVAL;
 930                }
 931        }
 932
 933        for (cat = 1; cat <= LPROPS_HEAP_CNT; cat++) {
 934                struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
 935
 936                for (i = 0; i < heap->cnt; i++) {
 937                        lprops = heap->arr[i];
 938                        if (!lprops) {
 939                                ubifs_err("null ptr in LPT heap cat %d", cat);
 940                                return -EINVAL;
 941                        }
 942                        if (lprops->hpos != i) {
 943                                ubifs_err("bad ptr in LPT heap cat %d", cat);
 944                                return -EINVAL;
 945                        }
 946                        if (lprops->flags & LPROPS_TAKEN) {
 947                                ubifs_err("taken LEB in LPT heap cat %d", cat);
 948                                return -EINVAL;
 949                        }
 950                }
 951        }
 952
 953        return 0;
 954}
 955
 956void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
 957                    int add_pos)
 958{
 959        int i = 0, j, err = 0;
 960
 961        if (!dbg_is_chk_gen(c) && !dbg_is_chk_lprops(c))
 962                return;
 963
 964        for (i = 0; i < heap->cnt; i++) {
 965                struct ubifs_lprops *lprops = heap->arr[i];
 966                struct ubifs_lprops *lp;
 967
 968                if (i != add_pos)
 969                        if ((lprops->flags & LPROPS_CAT_MASK) != cat) {
 970                                err = 1;
 971                                goto out;
 972                        }
 973                if (lprops->hpos != i) {
 974                        err = 2;
 975                        goto out;
 976                }
 977                lp = ubifs_lpt_lookup(c, lprops->lnum);
 978                if (IS_ERR(lp)) {
 979                        err = 3;
 980                        goto out;
 981                }
 982                if (lprops != lp) {
 983                        dbg_msg("lprops %zx lp %zx lprops->lnum %d lp->lnum %d",
 984                                (size_t)lprops, (size_t)lp, lprops->lnum,
 985                                lp->lnum);
 986                        err = 4;
 987                        goto out;
 988                }
 989                for (j = 0; j < i; j++) {
 990                        lp = heap->arr[j];
 991                        if (lp == lprops) {
 992                                err = 5;
 993                                goto out;
 994                        }
 995                        if (lp->lnum == lprops->lnum) {
 996                                err = 6;
 997                                goto out;
 998                        }
 999                }
1000        }
1001out:
1002        if (err) {
1003                dbg_msg("failed cat %d hpos %d err %d", cat, i, err);
1004                dbg_dump_stack();
1005                dbg_dump_heap(c, heap, cat);
1006        }
1007}
1008
1009/**
1010 * scan_check_cb - scan callback.
1011 * @c: the UBIFS file-system description object
1012 * @lp: LEB properties to scan
1013 * @in_tree: whether the LEB properties are in main memory
1014 * @lst: lprops statistics to update
1015 *
1016 * This function returns a code that indicates whether the scan should continue
1017 * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
1018 * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
1019 * (%LPT_SCAN_STOP).
1020 */
1021static int scan_check_cb(struct ubifs_info *c,
1022                         const struct ubifs_lprops *lp, int in_tree,
1023                         struct ubifs_lp_stats *lst)
1024{
1025        struct ubifs_scan_leb *sleb;
1026        struct ubifs_scan_node *snod;
1027        int cat, lnum = lp->lnum, is_idx = 0, used = 0, free, dirty, ret;
1028        void *buf = NULL;
1029
1030        cat = lp->flags & LPROPS_CAT_MASK;
1031        if (cat != LPROPS_UNCAT) {
1032                cat = ubifs_categorize_lprops(c, lp);
1033                if (cat != (lp->flags & LPROPS_CAT_MASK)) {
1034                        ubifs_err("bad LEB category %d expected %d",
1035                                  (lp->flags & LPROPS_CAT_MASK), cat);
1036                        return -EINVAL;
1037                }
1038        }
1039
1040        /* Check lp is on its category list (if it has one) */
1041        if (in_tree) {
1042                struct list_head *list = NULL;
1043
1044                switch (cat) {
1045                case LPROPS_EMPTY:
1046                        list = &c->empty_list;
1047                        break;
1048                case LPROPS_FREEABLE:
1049                        list = &c->freeable_list;
1050                        break;
1051                case LPROPS_FRDI_IDX:
1052                        list = &c->frdi_idx_list;
1053                        break;
1054                case LPROPS_UNCAT:
1055                        list = &c->uncat_list;
1056                        break;
1057                }
1058                if (list) {
1059                        struct ubifs_lprops *lprops;
1060                        int found = 0;
1061
1062                        list_for_each_entry(lprops, list, list) {
1063                                if (lprops == lp) {
1064                                        found = 1;
1065                                        break;
1066                                }
1067                        }
1068                        if (!found) {
1069                                ubifs_err("bad LPT list (category %d)", cat);
1070                                return -EINVAL;
1071                        }
1072                }
1073        }
1074
1075        /* Check lp is on its category heap (if it has one) */
1076        if (in_tree && cat > 0 && cat <= LPROPS_HEAP_CNT) {
1077                struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
1078
1079                if ((lp->hpos != -1 && heap->arr[lp->hpos]->lnum != lnum) ||
1080                    lp != heap->arr[lp->hpos]) {
1081                        ubifs_err("bad LPT heap (category %d)", cat);
1082                        return -EINVAL;
1083                }
1084        }
1085
1086        buf = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
1087        if (!buf)
1088                return -ENOMEM;
1089
1090        /*
1091         * After an unclean unmount, empty and freeable LEBs
1092         * may contain garbage - do not scan them.
1093         */
1094        if (lp->free == c->leb_size) {
1095                lst->empty_lebs += 1;
1096                lst->total_free += c->leb_size;
1097                lst->total_dark += ubifs_calc_dark(c, c->leb_size);
1098                return LPT_SCAN_CONTINUE;
1099        }
1100        if (lp->free + lp->dirty == c->leb_size &&
1101            !(lp->flags & LPROPS_INDEX)) {
1102                lst->total_free  += lp->free;
1103                lst->total_dirty += lp->dirty;
1104                lst->total_dark  +=  ubifs_calc_dark(c, c->leb_size);
1105                return LPT_SCAN_CONTINUE;
1106        }
1107
1108        sleb = ubifs_scan(c, lnum, 0, buf, 0);
1109        if (IS_ERR(sleb)) {
1110                ret = PTR_ERR(sleb);
1111                if (ret == -EUCLEAN) {
1112                        dbg_dump_lprops(c);
1113                        dbg_dump_budg(c, &c->bi);
1114                }
1115                goto out;
1116        }
1117
1118        is_idx = -1;
1119        list_for_each_entry(snod, &sleb->nodes, list) {
1120                int found, level = 0;
1121
1122                cond_resched();
1123
1124                if (is_idx == -1)
1125                        is_idx = (snod->type == UBIFS_IDX_NODE) ? 1 : 0;
1126
1127                if (is_idx && snod->type != UBIFS_IDX_NODE) {
1128                        ubifs_err("indexing node in data LEB %d:%d",
1129                                  lnum, snod->offs);
1130                        goto out_destroy;
1131                }
1132
1133                if (snod->type == UBIFS_IDX_NODE) {
1134                        struct ubifs_idx_node *idx = snod->node;
1135
1136                        key_read(c, ubifs_idx_key(c, idx), &snod->key);
1137                        level = le16_to_cpu(idx->level);
1138                }
1139
1140                found = ubifs_tnc_has_node(c, &snod->key, level, lnum,
1141                                           snod->offs, is_idx);
1142                if (found) {
1143                        if (found < 0)
1144                                goto out_destroy;
1145                        used += ALIGN(snod->len, 8);
1146                }
1147        }
1148
1149        free = c->leb_size - sleb->endpt;
1150        dirty = sleb->endpt - used;
1151
1152        if (free > c->leb_size || free < 0 || dirty > c->leb_size ||
1153            dirty < 0) {
1154                ubifs_err("bad calculated accounting for LEB %d: "
1155                          "free %d, dirty %d", lnum, free, dirty);
1156                goto out_destroy;
1157        }
1158
1159        if (lp->free + lp->dirty == c->leb_size &&
1160            free + dirty == c->leb_size)
1161                if ((is_idx && !(lp->flags & LPROPS_INDEX)) ||
1162                    (!is_idx && free == c->leb_size) ||
1163                    lp->free == c->leb_size) {
1164                        /*
1165                         * Empty or freeable LEBs could contain index
1166                         * nodes from an uncompleted commit due to an
1167                         * unclean unmount. Or they could be empty for
1168                         * the same reason. Or it may simply not have been
1169                         * unmapped.
1170                         */
1171                        free = lp->free;
1172                        dirty = lp->dirty;
1173                        is_idx = 0;
1174                    }
1175
1176        if (is_idx && lp->free + lp->dirty == free + dirty &&
1177            lnum != c->ihead_lnum) {
1178                /*
1179                 * After an unclean unmount, an index LEB could have a different
1180                 * amount of free space than the value recorded by lprops. That
1181                 * is because the in-the-gaps method may use free space or
1182                 * create free space (as a side-effect of using ubi_leb_change
1183                 * and not writing the whole LEB). The incorrect free space
1184                 * value is not a problem because the index is only ever
1185                 * allocated empty LEBs, so there will never be an attempt to
1186                 * write to the free space at the end of an index LEB - except
1187                 * by the in-the-gaps method for which it is not a problem.
1188                 */
1189                free = lp->free;
1190                dirty = lp->dirty;
1191        }
1192
1193        if (lp->free != free || lp->dirty != dirty)
1194                goto out_print;
1195
1196        if (is_idx && !(lp->flags & LPROPS_INDEX)) {
1197                if (free == c->leb_size)
1198                        /* Free but not unmapped LEB, it's fine */
1199                        is_idx = 0;
1200                else {
1201                        ubifs_err("indexing node without indexing "
1202                                  "flag");
1203                        goto out_print;
1204                }
1205        }
1206
1207        if (!is_idx && (lp->flags & LPROPS_INDEX)) {
1208                ubifs_err("data node with indexing flag");
1209                goto out_print;
1210        }
1211
1212        if (free == c->leb_size)
1213                lst->empty_lebs += 1;
1214
1215        if (is_idx)
1216                lst->idx_lebs += 1;
1217
1218        if (!(lp->flags & LPROPS_INDEX))
1219                lst->total_used += c->leb_size - free - dirty;
1220        lst->total_free += free;
1221        lst->total_dirty += dirty;
1222
1223        if (!(lp->flags & LPROPS_INDEX)) {
1224                int spc = free + dirty;
1225
1226                if (spc < c->dead_wm)
1227                        lst->total_dead += spc;
1228                else
1229                        lst->total_dark += ubifs_calc_dark(c, spc);
1230        }
1231
1232        ubifs_scan_destroy(sleb);
1233        vfree(buf);
1234        return LPT_SCAN_CONTINUE;
1235
1236out_print:
1237        ubifs_err("bad accounting of LEB %d: free %d, dirty %d flags %#x, "
1238                  "should be free %d, dirty %d",
1239                  lnum, lp->free, lp->dirty, lp->flags, free, dirty);
1240        dbg_dump_leb(c, lnum);
1241out_destroy:
1242        ubifs_scan_destroy(sleb);
1243        ret = -EINVAL;
1244out:
1245        vfree(buf);
1246        return ret;
1247}
1248
1249/**
1250 * dbg_check_lprops - check all LEB properties.
1251 * @c: UBIFS file-system description object
1252 *
1253 * This function checks all LEB properties and makes sure they are all correct.
1254 * It returns zero if everything is fine, %-EINVAL if there is an inconsistency
1255 * and other negative error codes in case of other errors. This function is
1256 * called while the file system is locked (because of commit start), so no
1257 * additional locking is required. Note that locking the LPT mutex would cause
1258 * a circular lock dependency with the TNC mutex.
1259 */
1260int dbg_check_lprops(struct ubifs_info *c)
1261{
1262        int i, err;
1263        struct ubifs_lp_stats lst;
1264
1265        if (!dbg_is_chk_lprops(c))
1266                return 0;
1267
1268        /*
1269         * As we are going to scan the media, the write buffers have to be
1270         * synchronized.
1271         */
1272        for (i = 0; i < c->jhead_cnt; i++) {
1273                err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
1274                if (err)
1275                        return err;
1276        }
1277
1278        memset(&lst, 0, sizeof(struct ubifs_lp_stats));
1279        err = ubifs_lpt_scan_nolock(c, c->main_first, c->leb_cnt - 1,
1280                                    (ubifs_lpt_scan_callback)scan_check_cb,
1281                                    &lst);
1282        if (err && err != -ENOSPC)
1283                goto out;
1284
1285        if (lst.empty_lebs != c->lst.empty_lebs ||
1286            lst.idx_lebs != c->lst.idx_lebs ||
1287            lst.total_free != c->lst.total_free ||
1288            lst.total_dirty != c->lst.total_dirty ||
1289            lst.total_used != c->lst.total_used) {
1290                ubifs_err("bad overall accounting");
1291                ubifs_err("calculated: empty_lebs %d, idx_lebs %d, "
1292                          "total_free %lld, total_dirty %lld, total_used %lld",
1293                          lst.empty_lebs, lst.idx_lebs, lst.total_free,
1294                          lst.total_dirty, lst.total_used);
1295                ubifs_err("read from lprops: empty_lebs %d, idx_lebs %d, "
1296                          "total_free %lld, total_dirty %lld, total_used %lld",
1297                          c->lst.empty_lebs, c->lst.idx_lebs, c->lst.total_free,
1298                          c->lst.total_dirty, c->lst.total_used);
1299                err = -EINVAL;
1300                goto out;
1301        }
1302
1303        if (lst.total_dead != c->lst.total_dead ||
1304            lst.total_dark != c->lst.total_dark) {
1305                ubifs_err("bad dead/dark space accounting");
1306                ubifs_err("calculated: total_dead %lld, total_dark %lld",
1307                          lst.total_dead, lst.total_dark);
1308                ubifs_err("read from lprops: total_dead %lld, total_dark %lld",
1309                          c->lst.total_dead, c->lst.total_dark);
1310                err = -EINVAL;
1311                goto out;
1312        }
1313
1314        err = dbg_check_cats(c);
1315out:
1316        return err;
1317}
1318
1319#endif /* CONFIG_UBIFS_FS_DEBUG */
1320