fs/ubifs/lprops.c

   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  */
  38 static 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  */
  62 static 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  */
  99 static 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  */
 178 static 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  */
 226 static 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  */
 256 static 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  */
 275 void 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 uncategorized */
 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  */
 315 static 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  */
 349 void 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  * uncategorized even though it has enough space for us now. If that is the case
 379  * this function will put the LEB back onto a heap.
 380  */
 381 void 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  */
 404 int 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 recategorize
 440  *
 441  * LEB properties are categorized to enable fast find operations. When the LEB
 442  * properties change they must be recategorized.
 443  */
 444 static 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  * 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 amount of dark space in an LEB which has @spc bytes
 469  * of free and dirty space. Returns the calculations result.
 470  *
 471  * Dark space is the space which is not always usable - it depends on which
 472  * nodes are written in which order. E.g., if an LEB has only 512 free bytes,
 473  * it is dark space, because it cannot fit a large data node. So UBIFS cannot
 474  * count on this LEB and treat these 512 bytes as usable because it is not true
 475  * if, for example, only big chunks of uncompressible data will be written to
 476  * the FS.
 477  */
 478 static int calc_dark(struct ubifs_info *c, int spc)
 479 {
 480         ubifs_assert(!(spc & 7));
 481
 482         if (spc < c->dark_wm)
 483                 return spc;
 484
 485         /*
 486          * If we have slightly more space then the dark space watermark, we can
 487          * anyway safely assume it we'll be able to write a node of the
 488          * smallest size there.
 489          */
 490         if (spc - c->dark_wm < MIN_WRITE_SZ)
 491                 return spc - MIN_WRITE_SZ;
 492
 493         return c->dark_wm;
 494 }
 495
 496 /**
 497  * is_lprops_dirty - determine if LEB properties are dirty.
 498  * @c: the UBIFS file-system description object
 499  * @lprops: LEB properties to test
 500  */
 501 static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops)
 502 {
 503         struct ubifs_pnode *pnode;
 504         int pos;
 505
 506         pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1);
 507         pnode = (struct ubifs_pnode *)container_of(lprops - pos,
 508                                                    struct ubifs_pnode,
 509                                                    lprops[0]);
 510         return !test_bit(COW_ZNODE, &pnode->flags) &&
 511                test_bit(DIRTY_CNODE, &pnode->flags);
 512 }
 513
 514 /**
 515  * ubifs_change_lp - change LEB properties.
 516  * @c: the UBIFS file-system description object
 517  * @lp: LEB properties to change
 518  * @free: new free space amount
 519  * @dirty: new dirty space amount
 520  * @flags: new flags
 521  * @idx_gc_cnt: change to the count of idx_gc list
 522  *
 523  * This function changes LEB properties (@free, @dirty or @flag). However, the
 524  * property which has the %LPROPS_NC value is not changed. Returns a pointer to
 525  * the updated LEB properties on success and a negative error code on failure.
 526  *
 527  * Note, the LEB properties may have had to be copied (due to COW) and
 528  * consequently the pointer returned may not be the same as the pointer
 529  * passed.
 530  */
 531 const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
 532                                            const struct ubifs_lprops *lp,
 533                                            int free, int dirty, int flags,
 534                                            int idx_gc_cnt)
 535 {
 536         /*
 537          * This is the only function that is allowed to change lprops, so we
 538          * discard the const qualifier.
 539          */
 540         struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp;
 541
 542         dbg_lp("LEB %d, free %d, dirty %d, flags %d",
 543                lprops->lnum, free, dirty, flags);
 544
 545         ubifs_assert(mutex_is_locked(&c->lp_mutex));
 546         ubifs_assert(c->lst.empty_lebs >= 0 &&
 547                      c->lst.empty_lebs <= c->main_lebs);
 548         ubifs_assert(c->freeable_cnt >= 0);
 549         ubifs_assert(c->freeable_cnt <= c->main_lebs);
 550         ubifs_assert(c->lst.taken_empty_lebs >= 0);
 551         ubifs_assert(c->lst.taken_empty_lebs <= c->lst.empty_lebs);
 552         ubifs_assert(!(c->lst.total_free & 7) && !(c->lst.total_dirty & 7));
 553         ubifs_assert(!(c->lst.total_dead & 7) && !(c->lst.total_dark & 7));
 554         ubifs_assert(!(c->lst.total_used & 7));
 555         ubifs_assert(free == LPROPS_NC || free >= 0);
 556         ubifs_assert(dirty == LPROPS_NC || dirty >= 0);
 557
 558         if (!is_lprops_dirty(c, lprops)) {
 559                 lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum);
 560                 if (IS_ERR(lprops))
 561                         return lprops;
 562         } else
 563                 ubifs_assert(lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum));
 564
 565         ubifs_assert(!(lprops->free & 7) && !(lprops->dirty & 7));
 566
 567         spin_lock(&c->space_lock);
 568         if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
 569                 c->lst.taken_empty_lebs -= 1;
 570
 571         if (!(lprops->flags & LPROPS_INDEX)) {
 572                 int old_spc;
 573
 574                 old_spc = lprops->free + lprops->dirty;
 575                 if (old_spc < c->dead_wm)
 576                         c->lst.total_dead -= old_spc;
 577                 else
 578                         c->lst.total_dark -= calc_dark(c, old_spc);
 579
 580                 c->lst.total_used -= c->leb_size - old_spc;
 581         }
 582
 583         if (free != LPROPS_NC) {
 584                 free = ALIGN(free, 8);
 585                 c->lst.total_free += free - lprops->free;
 586
 587                 /* Increase or decrease empty LEBs counter if needed */
 588                 if (free == c->leb_size) {
 589                         if (lprops->free != c->leb_size)
 590                                 c->lst.empty_lebs += 1;
 591                 } else if (lprops->free == c->leb_size)
 592                         c->lst.empty_lebs -= 1;
 593                 lprops->free = free;
 594         }
 595
 596         if (dirty != LPROPS_NC) {
 597                 dirty = ALIGN(dirty, 8);
 598                 c->lst.total_dirty += dirty - lprops->dirty;
 599                 lprops->dirty = dirty;
 600         }
 601
 602         if (flags != LPROPS_NC) {
 603                 /* Take care about indexing LEBs counter if needed */
 604                 if ((lprops->flags & LPROPS_INDEX)) {
 605                         if (!(flags & LPROPS_INDEX))
 606                                 c->lst.idx_lebs -= 1;
 607                 } else if (flags & LPROPS_INDEX)
 608                         c->lst.idx_lebs += 1;
 609                 lprops->flags = flags;
 610         }
 611
 612         if (!(lprops->flags & LPROPS_INDEX)) {
 613                 int new_spc;
 614
 615                 new_spc = lprops->free + lprops->dirty;
 616                 if (new_spc < c->dead_wm)
 617                         c->lst.total_dead += new_spc;
 618                 else
 619                         c->lst.total_dark += calc_dark(c, new_spc);
 620
 621                 c->lst.total_used += c->leb_size - new_spc;
 622         }
 623
 624         if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
 625                 c->lst.taken_empty_lebs += 1;
 626
 627         change_category(c, lprops);
 628         c->idx_gc_cnt += idx_gc_cnt;
 629         spin_unlock(&c->space_lock);
 630         return lprops;
 631 }
 632
 633 /**
 634  * ubifs_get_lp_stats - get lprops statistics.
 635  * @c: UBIFS file-system description object
 636  * @st: return statistics
 637  */
 638 void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst)
 639 {
 640         spin_lock(&c->space_lock);
 641         memcpy(lst, &c->lst, sizeof(struct ubifs_lp_stats));
 642         spin_unlock(&c->space_lock);
 643 }
 644
 645 /**
 646  * ubifs_change_one_lp - change LEB properties.
 647  * @c: the UBIFS file-system description object
 648  * @lnum: LEB to change properties for
 649  * @free: amount of free space
 650  * @dirty: amount of dirty space
 651  * @flags_set: flags to set
 652  * @flags_clean: flags to clean
 653  * @idx_gc_cnt: change to the count of idx_gc list
 654  *
 655  * This function changes properties of LEB @lnum. It is a helper wrapper over
 656  * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the
 657  * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and
 658  * a negative error code in case of failure.
 659  */
 660 int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
 661                         int flags_set, int flags_clean, int idx_gc_cnt)
 662 {
 663         int err = 0, flags;
 664         const struct ubifs_lprops *lp;
 665
 666         ubifs_get_lprops(c);
 667
 668         lp = ubifs_lpt_lookup_dirty(c, lnum);
 669         if (IS_ERR(lp)) {
 670                 err = PTR_ERR(lp);
 671                 goto out;
 672         }
 673
 674         flags = (lp->flags | flags_set) & ~flags_clean;
 675         lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt);
 676         if (IS_ERR(lp))
 677                 err = PTR_ERR(lp);
 678
 679 out:
 680         ubifs_release_lprops(c);
 681         if (err)
 682                 ubifs_err("cannot change properties of LEB %d, error %d",
 683                           lnum, err);
 684         return err;
 685 }
 686
 687 /**
 688  * ubifs_update_one_lp - update LEB properties.
 689  * @c: the UBIFS file-system description object
 690  * @lnum: LEB to change properties for
 691  * @free: amount of free space
 692  * @dirty: amount of dirty space to add
 693  * @flags_set: flags to set
 694  * @flags_clean: flags to clean
 695  *
 696  * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to
 697  * current dirty space, not substitutes it.
 698  */
 699 int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
 700                         int flags_set, int flags_clean)
 701 {
 702         int err = 0, flags;
 703         const struct ubifs_lprops *lp;
 704
 705         ubifs_get_lprops(c);
 706
 707         lp = ubifs_lpt_lookup_dirty(c, lnum);
 708         if (IS_ERR(lp)) {
 709                 err = PTR_ERR(lp);
 710                 goto out;
 711         }
 712
 713         flags = (lp->flags | flags_set) & ~flags_clean;
 714         lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0);
 715         if (IS_ERR(lp))
 716                 err = PTR_ERR(lp);
 717
 718 out:
 719         ubifs_release_lprops(c);
 720         if (err)
 721                 ubifs_err("cannot update properties of LEB %d, error %d",
 722                           lnum, err);
 723         return err;
 724 }
 725
 726 /**
 727  * ubifs_read_one_lp - read LEB properties.
 728  * @c: the UBIFS file-system description object
 729  * @lnum: LEB to read properties for
 730  * @lp: where to store read properties
 731  *
 732  * This helper function reads properties of a LEB @lnum and stores them in @lp.
 733  * Returns zero in case of success and a negative error code in case of
 734  * failure.
 735  */
 736 int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp)
 737 {
 738         int err = 0;
 739         const struct ubifs_lprops *lpp;
 740
 741         ubifs_get_lprops(c);
 742
 743         lpp = ubifs_lpt_lookup(c, lnum);
 744         if (IS_ERR(lpp)) {
 745                 err = PTR_ERR(lpp);
 746                 ubifs_err("cannot read properties of LEB %d, error %d",
 747                           lnum, err);
 748                 goto out;
 749         }
 750
 751         memcpy(lp, lpp, sizeof(struct ubifs_lprops));
 752
 753 out:
 754         ubifs_release_lprops(c);
 755         return err;
 756 }
 757
 758 /**
 759  * ubifs_fast_find_free - try to find a LEB with free space quickly.
 760  * @c: the UBIFS file-system description object
 761  *
 762  * This function returns LEB properties for a LEB with free space or %NULL if
 763  * the function is unable to find a LEB quickly.
 764  */
 765 const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c)
 766 {
 767         struct ubifs_lprops *lprops;
 768         struct ubifs_lpt_heap *heap;
 769
 770         ubifs_assert(mutex_is_locked(&c->lp_mutex));
 771
 772         heap = &c->lpt_heap[LPROPS_FREE - 1];
 773         if (heap->cnt == 0)
 774                 return NULL;
 775
 776         lprops = heap->arr[0];
 777         ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
 778         ubifs_assert(!(lprops->flags & LPROPS_INDEX));
 779         return lprops;
 780 }
 781
 782 /**
 783  * ubifs_fast_find_empty - try to find an empty LEB quickly.
 784  * @c: the UBIFS file-system description object
 785  *
 786  * This function returns LEB properties for an empty LEB or %NULL if the
 787  * function is unable to find an empty LEB quickly.
 788  */
 789 const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c)
 790 {
 791         struct ubifs_lprops *lprops;
 792
 793         ubifs_assert(mutex_is_locked(&c->lp_mutex));
 794
 795         if (list_empty(&c->empty_list))
 796                 return NULL;
 797
 798         lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list);
 799         ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
 800         ubifs_assert(!(lprops->flags & LPROPS_INDEX));
 801         ubifs_assert(lprops->free == c->leb_size);
 802         return lprops;
 803 }
 804
 805 /**
 806  * ubifs_fast_find_freeable - try to find a freeable LEB quickly.
 807  * @c: the UBIFS file-system description object
 808  *
 809  * This function returns LEB properties for a freeable LEB or %NULL if the
 810  * function is unable to find a freeable LEB quickly.
 811  */
 812 const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c)
 813 {
 814         struct ubifs_lprops *lprops;
 815
 816         ubifs_assert(mutex_is_locked(&c->lp_mutex));
 817
 818         if (list_empty(&c->freeable_list))
 819                 return NULL;
 820
 821         lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list);
 822         ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
 823         ubifs_assert(!(lprops->flags & LPROPS_INDEX));
 824         ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
 825         ubifs_assert(c->freeable_cnt > 0);
 826         return lprops;
 827 }
 828
 829 /**
 830  * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly.
 831  * @c: the UBIFS file-system description object
 832  *
 833  * This function returns LEB properties for a freeable index LEB or %NULL if the
 834  * function is unable to find a freeable index LEB quickly.
 835  */
 836 const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c)
 837 {
 838         struct ubifs_lprops *lprops;
 839
 840         ubifs_assert(mutex_is_locked(&c->lp_mutex));
 841
 842         if (list_empty(&c->frdi_idx_list))
 843                 return NULL;
 844
 845         lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list);
 846         ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
 847         ubifs_assert((lprops->flags & LPROPS_INDEX));
 848         ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
 849         return lprops;
 850 }
 851
 852 #ifdef CONFIG_UBIFS_FS_DEBUG
 853
 854 /**
 855  * dbg_check_cats - check category heaps and lists.
 856  * @c: UBIFS file-system description object
 857  *
 858  * This function returns %0 on success and a negative error code on failure.
 859  */
 860 int dbg_check_cats(struct ubifs_info *c)
 861 {
 862         struct ubifs_lprops *lprops;
 863         struct list_head *pos;
 864         int i, cat;
 865
 866         if (!(ubifs_chk_flags & (UBIFS_CHK_GEN | UBIFS_CHK_LPROPS)))
 867                 return 0;
 868
 869         list_for_each_entry(lprops, &c->empty_list, list) {
 870                 if (lprops->free != c->leb_size) {
 871                         ubifs_err("non-empty LEB %d on empty list "
 872                                   "(free %d dirty %d flags %d)", lprops->lnum,
 873                                   lprops->free, lprops->dirty, lprops->flags);
 874                         return -EINVAL;
 875                 }
 876                 if (lprops->flags & LPROPS_TAKEN) {
 877                         ubifs_err("taken LEB %d on empty list "
 878                                   "(free %d dirty %d flags %d)", lprops->lnum,
 879                                   lprops->free, lprops->dirty, lprops->flags);
 880                         return -EINVAL;
 881                 }
 882         }
 883
 884         i = 0;
 885         list_for_each_entry(lprops, &c->freeable_list, list) {
 886                 if (lprops->free + lprops->dirty != c->leb_size) {
 887                         ubifs_err("non-freeable LEB %d on freeable list "
 888                                   "(free %d dirty %d flags %d)", lprops->lnum,
 889                                   lprops->free, lprops->dirty, lprops->flags);
 890                         return -EINVAL;
 891                 }
 892                 if (lprops->flags & LPROPS_TAKEN) {
 893                         ubifs_err("taken LEB %d on freeable list "
 894                                   "(free %d dirty %d flags %d)", lprops->lnum,
 895                                   lprops->free, lprops->dirty, lprops->flags);
 896                         return -EINVAL;
 897                 }
 898                 i += 1;
 899         }
 900         if (i != c->freeable_cnt) {
 901                 ubifs_err("freeable list count %d expected %d", i,
 902                           c->freeable_cnt);
 903                 return -EINVAL;
 904         }
 905
 906         i = 0;
 907         list_for_each(pos, &c->idx_gc)
 908                 i += 1;
 909         if (i != c->idx_gc_cnt) {
 910                 ubifs_err("idx_gc list count %d expected %d", i,
 911                           c->idx_gc_cnt);
 912                 return -EINVAL;
 913         }
 914
 915         list_for_each_entry(lprops, &c->frdi_idx_list, list) {
 916                 if (lprops->free + lprops->dirty != c->leb_size) {
 917                         ubifs_err("non-freeable LEB %d on frdi_idx list "
 918                                   "(free %d dirty %d flags %d)", lprops->lnum,
 919                                   lprops->free, lprops->dirty, lprops->flags);
 920                         return -EINVAL;
 921                 }
 922                 if (lprops->flags & LPROPS_TAKEN) {
 923                         ubifs_err("taken LEB %d on frdi_idx list "
 924                                   "(free %d dirty %d flags %d)", lprops->lnum,
 925                                   lprops->free, lprops->dirty, lprops->flags);
 926                         return -EINVAL;
 927                 }
 928                 if (!(lprops->flags & LPROPS_INDEX)) {
 929                         ubifs_err("non-index LEB %d on frdi_idx list "
 930                                   "(free %d dirty %d flags %d)", lprops->lnum,
 931                                   lprops->free, lprops->dirty, lprops->flags);
 932                         return -EINVAL;
 933                 }
 934         }
 935
 936         for (cat = 1; cat <= LPROPS_HEAP_CNT; cat++) {
 937                 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
 938
 939                 for (i = 0; i < heap->cnt; i++) {
 940                         lprops = heap->arr[i];
 941                         if (!lprops) {
 942                                 ubifs_err("null ptr in LPT heap cat %d", cat);
 943                                 return -EINVAL;
 944                         }
 945                         if (lprops->hpos != i) {
 946                                 ubifs_err("bad ptr in LPT heap cat %d", cat);
 947                                 return -EINVAL;
 948                         }
 949                         if (lprops->flags & LPROPS_TAKEN) {
 950                                 ubifs_err("taken LEB in LPT heap cat %d", cat);
 951                                 return -EINVAL;
 952                         }
 953                 }
 954         }
 955
 956         return 0;
 957 }
 958
 959 void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
 960                     int add_pos)
 961 {
 962         int i = 0, j, err = 0;
 963
 964         if (!(ubifs_chk_flags & (UBIFS_CHK_GEN | UBIFS_CHK_LPROPS)))
 965                 return;
 966
 967         for (i = 0; i < heap->cnt; i++) {
 968                 struct ubifs_lprops *lprops = heap->arr[i];
 969                 struct ubifs_lprops *lp;
 970
 971                 if (i != add_pos)
 972                         if ((lprops->flags & LPROPS_CAT_MASK) != cat) {
 973                                 err = 1;
 974                                 goto out;
 975                         }
 976                 if (lprops->hpos != i) {
 977                         err = 2;
 978                         goto out;
 979                 }
 980                 lp = ubifs_lpt_lookup(c, lprops->lnum);
 981                 if (IS_ERR(lp)) {
 982                         err = 3;
 983                         goto out;
 984                 }
 985                 if (lprops != lp) {
 986                         dbg_msg("lprops %zx lp %zx lprops->lnum %d lp->lnum %d",
 987                                 (size_t)lprops, (size_t)lp, lprops->lnum,
 988                                 lp->lnum);
 989                         err = 4;
 990                         goto out;
 991                 }
 992                 for (j = 0; j < i; j++) {
 993                         lp = heap->arr[j];
 994                         if (lp == lprops) {
 995                                 err = 5;
 996                                 goto out;
 997                         }
 998                         if (lp->lnum == lprops->lnum) {
 999                                 err = 6;
1000                                 goto out;
1001                         }
1002                 }
1003         }
1004 out:
1005         if (err) {
1006                 dbg_msg("failed cat %d hpos %d err %d", cat, i, err);
1007                 dbg_dump_stack();
1008                 dbg_dump_heap(c, heap, cat);
1009         }
1010 }
1011
1012 /**
1013  * struct scan_check_data - data provided to scan callback function.
1014  * @lst: LEB properties statistics
1015  * @err: error code
1016  */
1017 struct scan_check_data {
1018         struct ubifs_lp_stats lst;
1019         int err;
1020 };
1021
1022 /**
1023  * scan_check_cb - scan callback.
1024  * @c: the UBIFS file-system description object
1025  * @lp: LEB properties to scan
1026  * @in_tree: whether the LEB properties are in main memory
1027  * @data: information passed to and from the caller of the scan
1028  *
1029  * This function returns a code that indicates whether the scan should continue
1030  * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
1031  * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
1032  * (%LPT_SCAN_STOP).
1033  */
1034 static int scan_check_cb(struct ubifs_info *c,
1035                          const struct ubifs_lprops *lp, int in_tree,
1036                          struct scan_check_data *data)
1037 {
1038         struct ubifs_scan_leb *sleb;
1039         struct ubifs_scan_node *snod;
1040         struct ubifs_lp_stats *lst = &data->lst;
1041         int cat, lnum = lp->lnum, is_idx = 0, used = 0, free, dirty;
1042
1043         cat = lp->flags & LPROPS_CAT_MASK;
1044         if (cat != LPROPS_UNCAT) {
1045                 cat = ubifs_categorize_lprops(c, lp);
1046                 if (cat != (lp->flags & LPROPS_CAT_MASK)) {
1047                         ubifs_err("bad LEB category %d expected %d",
1048                                   (lp->flags & LPROPS_CAT_MASK), cat);
1049                         goto out;
1050                 }
1051         }
1052
1053         /* Check lp is on its category list (if it has one) */
1054         if (in_tree) {
1055                 struct list_head *list = NULL;
1056
1057                 switch (cat) {
1058                 case LPROPS_EMPTY:
1059                         list = &c->empty_list;
1060                         break;
1061                 case LPROPS_FREEABLE:
1062                         list = &c->freeable_list;
1063                         break;
1064                 case LPROPS_FRDI_IDX:
1065                         list = &c->frdi_idx_list;
1066                         break;
1067                 case LPROPS_UNCAT:
1068                         list = &c->uncat_list;
1069                         break;
1070                 }
1071                 if (list) {
1072                         struct ubifs_lprops *lprops;
1073                         int found = 0;
1074
1075                         list_for_each_entry(lprops, list, list) {
1076                                 if (lprops == lp) {
1077                                         found = 1;
1078                                         break;
1079                                 }
1080                         }
1081                         if (!found) {
1082                                 ubifs_err("bad LPT list (category %d)", cat);
1083                                 goto out;
1084                         }
1085                 }
1086         }
1087
1088         /* Check lp is on its category heap (if it has one) */
1089         if (in_tree && cat > 0 && cat <= LPROPS_HEAP_CNT) {
1090                 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
1091
1092                 if ((lp->hpos != -1 && heap->arr[lp->hpos]->lnum != lnum) ||
1093                     lp != heap->arr[lp->hpos]) {
1094                         ubifs_err("bad LPT heap (category %d)", cat);
1095                         goto out;
1096                 }
1097         }
1098
1099         sleb = ubifs_scan(c, lnum, 0, c->dbg->buf);
1100         if (IS_ERR(sleb)) {
1101                 /*
1102                  * After an unclean unmount, empty and freeable LEBs
1103                  * may contain garbage.
1104                  */
1105                 if (lp->free == c->leb_size) {
1106                         ubifs_err("scan errors were in empty LEB "
1107                                   "- continuing checking");
1108                         lst->empty_lebs += 1;
1109                         lst->total_free += c->leb_size;
1110                         lst->total_dark += calc_dark(c, c->leb_size);
1111                         return LPT_SCAN_CONTINUE;
1112                 }
1113
1114                 if (lp->free + lp->dirty == c->leb_size &&
1115                     !(lp->flags & LPROPS_INDEX)) {
1116                         ubifs_err("scan errors were in freeable LEB "
1117                                   "- continuing checking");
1118                         lst->total_free  += lp->free;
1119                         lst->total_dirty += lp->dirty;
1120                         lst->total_dark  +=  calc_dark(c, c->leb_size);
1121                         return LPT_SCAN_CONTINUE;
1122                 }
1123                 data->err = PTR_ERR(sleb);
1124                 return LPT_SCAN_STOP;
1125         }
1126
1127         is_idx = -1;
1128         list_for_each_entry(snod, &sleb->nodes, list) {
1129                 int found, level = 0;
1130
1131                 cond_resched();
1132
1133                 if (is_idx == -1)
1134                         is_idx = (snod->type == UBIFS_IDX_NODE) ? 1 : 0;
1135
1136                 if (is_idx && snod->type != UBIFS_IDX_NODE) {
1137                         ubifs_err("indexing node in data LEB %d:%d",
1138                                   lnum, snod->offs);
1139                         goto out_destroy;
1140                 }
1141
1142                 if (snod->type == UBIFS_IDX_NODE) {
1143                         struct ubifs_idx_node *idx = snod->node;
1144
1145                         key_read(c, ubifs_idx_key(c, idx), &snod->key);
1146                         level = le16_to_cpu(idx->level);
1147                 }
1148
1149                 found = ubifs_tnc_has_node(c, &snod->key, level, lnum,
1150                                            snod->offs, is_idx);
1151                 if (found) {
1152                         if (found < 0)
1153                                 goto out_destroy;
1154                         used += ALIGN(snod->len, 8);
1155                 }
1156         }
1157
1158         free = c->leb_size - sleb->endpt;
1159         dirty = sleb->endpt - used;
1160
1161         if (free > c->leb_size || free < 0 || dirty > c->leb_size ||
1162             dirty < 0) {
1163                 ubifs_err("bad calculated accounting for LEB %d: "
1164                           "free %d, dirty %d", lnum, free, dirty);
1165                 goto out_destroy;
1166         }
1167
1168         if (lp->free + lp->dirty == c->leb_size &&
1169             free + dirty == c->leb_size)
1170                 if ((is_idx && !(lp->flags & LPROPS_INDEX)) ||
1171                     (!is_idx && free == c->leb_size) ||
1172                     lp->free == c->leb_size) {
1173                         /*
1174                          * Empty or freeable LEBs could contain index
1175                          * nodes from an uncompleted commit due to an
1176                          * unclean unmount. Or they could be empty for
1177                          * the same reason. Or it may simply not have been
1178                          * unmapped.
1179                          */
1180                         free = lp->free;
1181                         dirty = lp->dirty;
1182                         is_idx = 0;
1183                     }
1184
1185         if (is_idx && lp->free + lp->dirty == free + dirty &&
1186             lnum != c->ihead_lnum) {
1187                 /*
1188                  * After an unclean unmount, an index LEB could have a different
1189                  * amount of free space than the value recorded by lprops. That
1190                  * is because the in-the-gaps method may use free space or
1191                  * create free space (as a side-effect of using ubi_leb_change
1192                  * and not writing the whole LEB). The incorrect free space
1193                  * value is not a problem because the index is only ever
1194                  * allocated empty LEBs, so there will never be an attempt to
1195                  * write to the free space at the end of an index LEB - except
1196                  * by the in-the-gaps method for which it is not a problem.
1197                  */
1198                 free = lp->free;
1199                 dirty = lp->dirty;
1200         }
1201
1202         if (lp->free != free || lp->dirty != dirty)
1203                 goto out_print;
1204
1205         if (is_idx && !(lp->flags & LPROPS_INDEX)) {
1206                 if (free == c->leb_size)
1207                         /* Free but not unmapped LEB, it's fine */
1208                         is_idx = 0;
1209                 else {
1210                         ubifs_err("indexing node without indexing "
1211                                   "flag");
1212                         goto out_print;
1213                 }
1214         }
1215
1216         if (!is_idx && (lp->flags & LPROPS_INDEX)) {
1217                 ubifs_err("data node with indexing flag");
1218                 goto out_print;
1219         }
1220
1221         if (free == c->leb_size)
1222                 lst->empty_lebs += 1;
1223
1224         if (is_idx)
1225                 lst->idx_lebs += 1;
1226
1227         if (!(lp->flags & LPROPS_INDEX))
1228                 lst->total_used += c->leb_size - free - dirty;
1229         lst->total_free += free;
1230         lst->total_dirty += dirty;
1231
1232         if (!(lp->flags & LPROPS_INDEX)) {
1233                 int spc = free + dirty;
1234
1235                 if (spc < c->dead_wm)
1236                         lst->total_dead += spc;
1237                 else
1238                         lst->total_dark += calc_dark(c, spc);
1239         }
1240
1241         ubifs_scan_destroy(sleb);
1242         return LPT_SCAN_CONTINUE;
1243
1244 out_print:
1245         ubifs_err("bad accounting of LEB %d: free %d, dirty %d flags %#x, "
1246                   "should be free %d, dirty %d",
1247                   lnum, lp->free, lp->dirty, lp->flags, free, dirty);
1248         dbg_dump_leb(c, lnum);
1249 out_destroy:
1250         ubifs_scan_destroy(sleb);
1251 out:
1252         data->err = -EINVAL;
1253         return LPT_SCAN_STOP;
1254 }
1255
1256 /**
1257  * dbg_check_lprops - check all LEB properties.
1258  * @c: UBIFS file-system description object
1259  *
1260  * This function checks all LEB properties and makes sure they are all correct.
1261  * It returns zero if everything is fine, %-EINVAL if there is an inconsistency
1262  * and other negative error codes in case of other errors. This function is
1263  * called while the file system is locked (because of commit start), so no
1264  * additional locking is required. Note that locking the LPT mutex would cause
1265  * a circular lock dependency with the TNC mutex.
1266  */
1267 int dbg_check_lprops(struct ubifs_info *c)
1268 {
1269         int i, err;
1270         struct scan_check_data data;
1271         struct ubifs_lp_stats *lst = &data.lst;
1272
1273         if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
1274                 return 0;
1275
1276         /*
1277          * As we are going to scan the media, the write buffers have to be
1278          * synchronized.
1279          */
1280         for (i = 0; i < c->jhead_cnt; i++) {
1281                 err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
1282                 if (err)
1283                         return err;
1284         }
1285
1286         memset(lst, 0, sizeof(struct ubifs_lp_stats));
1287
1288         data.err = 0;
1289         err = ubifs_lpt_scan_nolock(c, c->main_first, c->leb_cnt - 1,
1290                                     (ubifs_lpt_scan_callback)scan_check_cb,
1291                                     &data);
1292         if (err && err != -ENOSPC)
1293                 goto out;
1294         if (data.err) {
1295                 err = data.err;
1296                 goto out;
1297         }
1298
1299         if (lst->empty_lebs != c->lst.empty_lebs ||
1300             lst->idx_lebs != c->lst.idx_lebs ||
1301             lst->total_free != c->lst.total_free ||
1302             lst->total_dirty != c->lst.total_dirty ||
1303             lst->total_used != c->lst.total_used) {
1304                 ubifs_err("bad overall accounting");
1305                 ubifs_err("calculated: empty_lebs %d, idx_lebs %d, "
1306                           "total_free %lld, total_dirty %lld, total_used %lld",
1307                           lst->empty_lebs, lst->idx_lebs, lst->total_free,
1308                           lst->total_dirty, lst->total_used);
1309                 ubifs_err("read from lprops: empty_lebs %d, idx_lebs %d, "
1310                           "total_free %lld, total_dirty %lld, total_used %lld",
1311                           c->lst.empty_lebs, c->lst.idx_lebs, c->lst.total_free,
1312                           c->lst.total_dirty, c->lst.total_used);
1313                 err = -EINVAL;
1314                 goto out;
1315         }
1316
1317         if (lst->total_dead != c->lst.total_dead ||
1318             lst->total_dark != c->lst.total_dark) {
1319                 ubifs_err("bad dead/dark space accounting");
1320                 ubifs_err("calculated: total_dead %lld, total_dark %lld",
1321                           lst->total_dead, lst->total_dark);
1322                 ubifs_err("read from lprops: total_dead %lld, total_dark %lld",
1323                           c->lst.total_dead, c->lst.total_dark);
1324                 err = -EINVAL;
1325                 goto out;
1326         }
1327
1328         err = dbg_check_cats(c);
1329 out:
1330         return err;
1331 }
1332
1333 #endif /* CONFIG_UBIFS_FS_DEBUG */