fs/ubifs/lprops.c

   1 /*
   2  * This file is part of UBIFS.
   3  *
   4  * Copyright (C) 2006-2008 Nokia Corporation.
   5  *
   6  * SPDX-License-Identifier:     GPL-2.0+
   7  *
   8  * Authors: Adrian Hunter
   9  *          Artem Bityutskiy (Битюцкий Артём)
  10  */
  11
  12 /*
  13  * This file implements the functions that access LEB properties and their
  14  * categories. LEBs are categorized based on the needs of UBIFS, and the
  15  * categories are stored as either heaps or lists to provide a fast way of
  16  * finding a LEB in a particular category. For example, UBIFS may need to find
  17  * an empty LEB for the journal, or a very dirty LEB for garbage collection.
  18  */
  19
  20 #define __UBOOT__
  21 #ifdef __UBOOT__
  22 #include <linux/err.h>
  23 #endif
  24 #include "ubifs.h"
  25
  26 /**
  27  * get_heap_comp_val - get the LEB properties value for heap comparisons.
  28  * @lprops: LEB properties
  29  * @cat: LEB category
  30  */
  31 static int get_heap_comp_val(struct ubifs_lprops *lprops, int cat)
  32 {
  33         switch (cat) {
  34         case LPROPS_FREE:
  35                 return lprops->free;
  36         case LPROPS_DIRTY_IDX:
  37                 return lprops->free + lprops->dirty;
  38         default:
  39                 return lprops->dirty;
  40         }
  41 }
  42
  43 /**
  44  * move_up_lpt_heap - move a new heap entry up as far as possible.
  45  * @c: UBIFS file-system description object
  46  * @heap: LEB category heap
  47  * @lprops: LEB properties to move
  48  * @cat: LEB category
  49  *
  50  * New entries to a heap are added at the bottom and then moved up until the
  51  * parent's value is greater.  In the case of LPT's category heaps, the value
  52  * is either the amount of free space or the amount of dirty space, depending
  53  * on the category.
  54  */
  55 static void move_up_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
  56                              struct ubifs_lprops *lprops, int cat)
  57 {
  58         int val1, val2, hpos;
  59
  60         hpos = lprops->hpos;
  61         if (!hpos)
  62                 return; /* Already top of the heap */
  63         val1 = get_heap_comp_val(lprops, cat);
  64         /* Compare to parent and, if greater, move up the heap */
  65         do {
  66                 int ppos = (hpos - 1) / 2;
  67
  68                 val2 = get_heap_comp_val(heap->arr[ppos], cat);
  69                 if (val2 >= val1)
  70                         return;
  71                 /* Greater than parent so move up */
  72                 heap->arr[ppos]->hpos = hpos;
  73                 heap->arr[hpos] = heap->arr[ppos];
  74                 heap->arr[ppos] = lprops;
  75                 lprops->hpos = ppos;
  76                 hpos = ppos;
  77         } while (hpos);
  78 }
  79
  80 /**
  81  * adjust_lpt_heap - move a changed heap entry up or down the heap.
  82  * @c: UBIFS file-system description object
  83  * @heap: LEB category heap
  84  * @lprops: LEB properties to move
  85  * @hpos: heap position of @lprops
  86  * @cat: LEB category
  87  *
  88  * Changed entries in a heap are moved up or down until the parent's value is
  89  * greater.  In the case of LPT's category heaps, the value is either the amount
  90  * of free space or the amount of dirty space, depending on the category.
  91  */
  92 static void adjust_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
  93                             struct ubifs_lprops *lprops, int hpos, int cat)
  94 {
  95         int val1, val2, val3, cpos;
  96
  97         val1 = get_heap_comp_val(lprops, cat);
  98         /* Compare to parent and, if greater than parent, move up the heap */
  99         if (hpos) {
 100                 int ppos = (hpos - 1) / 2;
 101
 102                 val2 = get_heap_comp_val(heap->arr[ppos], cat);
 103                 if (val1 > val2) {
 104                         /* Greater than parent so move up */
 105                         while (1) {
 106                                 heap->arr[ppos]->hpos = hpos;
 107                                 heap->arr[hpos] = heap->arr[ppos];
 108                                 heap->arr[ppos] = lprops;
 109                                 lprops->hpos = ppos;
 110                                 hpos = ppos;
 111                                 if (!hpos)
 112                                         return;
 113                                 ppos = (hpos - 1) / 2;
 114                                 val2 = get_heap_comp_val(heap->arr[ppos], cat);
 115                                 if (val1 <= val2)
 116                                         return;
 117                                 /* Still greater than parent so keep going */
 118                         }
 119                 }
 120         }
 121
 122         /* Not greater than parent, so compare to children */
 123         while (1) {
 124                 /* Compare to left child */
 125                 cpos = hpos * 2 + 1;
 126                 if (cpos >= heap->cnt)
 127                         return;
 128                 val2 = get_heap_comp_val(heap->arr[cpos], cat);
 129                 if (val1 < val2) {
 130                         /* Less than left child, so promote biggest child */
 131                         if (cpos + 1 < heap->cnt) {
 132                                 val3 = get_heap_comp_val(heap->arr[cpos + 1],
 133                                                          cat);
 134                                 if (val3 > val2)
 135                                         cpos += 1; /* Right child is bigger */
 136                         }
 137                         heap->arr[cpos]->hpos = hpos;
 138                         heap->arr[hpos] = heap->arr[cpos];
 139                         heap->arr[cpos] = lprops;
 140                         lprops->hpos = cpos;
 141                         hpos = cpos;
 142                         continue;
 143                 }
 144                 /* Compare to right child */
 145                 cpos += 1;
 146                 if (cpos >= heap->cnt)
 147                         return;
 148                 val3 = get_heap_comp_val(heap->arr[cpos], cat);
 149                 if (val1 < val3) {
 150                         /* Less than right child, so promote right child */
 151                         heap->arr[cpos]->hpos = hpos;
 152                         heap->arr[hpos] = heap->arr[cpos];
 153                         heap->arr[cpos] = lprops;
 154                         lprops->hpos = cpos;
 155                         hpos = cpos;
 156                         continue;
 157                 }
 158                 return;
 159         }
 160 }
 161
 162 /**
 163  * add_to_lpt_heap - add LEB properties to a LEB category heap.
 164  * @c: UBIFS file-system description object
 165  * @lprops: LEB properties to add
 166  * @cat: LEB category
 167  *
 168  * This function returns %1 if @lprops is added to the heap for LEB category
 169  * @cat, otherwise %0 is returned because the heap is full.
 170  */
 171 static int add_to_lpt_heap(struct ubifs_info *c, struct ubifs_lprops *lprops,
 172                            int cat)
 173 {
 174         struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
 175
 176         if (heap->cnt >= heap->max_cnt) {
 177                 const int b = LPT_HEAP_SZ / 2 - 1;
 178                 int cpos, val1, val2;
 179
 180                 /* Compare to some other LEB on the bottom of heap */
 181                 /* Pick a position kind of randomly */
 182                 cpos = (((size_t)lprops >> 4) & b) + b;
 183                 ubifs_assert(cpos >= b);
 184                 ubifs_assert(cpos < LPT_HEAP_SZ);
 185                 ubifs_assert(cpos < heap->cnt);
 186
 187                 val1 = get_heap_comp_val(lprops, cat);
 188                 val2 = get_heap_comp_val(heap->arr[cpos], cat);
 189                 if (val1 > val2) {
 190                         struct ubifs_lprops *lp;
 191
 192                         lp = heap->arr[cpos];
 193                         lp->flags &= ~LPROPS_CAT_MASK;
 194                         lp->flags |= LPROPS_UNCAT;
 195                         list_add(&lp->list, &c->uncat_list);
 196                         lprops->hpos = cpos;
 197                         heap->arr[cpos] = lprops;
 198                         move_up_lpt_heap(c, heap, lprops, cat);
 199                         dbg_check_heap(c, heap, cat, lprops->hpos);
 200                         return 1; /* Added to heap */
 201                 }
 202                 dbg_check_heap(c, heap, cat, -1);
 203                 return 0; /* Not added to heap */
 204         } else {
 205                 lprops->hpos = heap->cnt++;
 206                 heap->arr[lprops->hpos] = lprops;
 207                 move_up_lpt_heap(c, heap, lprops, cat);
 208                 dbg_check_heap(c, heap, cat, lprops->hpos);
 209                 return 1; /* Added to heap */
 210         }
 211 }
 212
 213 /**
 214  * remove_from_lpt_heap - remove LEB properties from a LEB category heap.
 215  * @c: UBIFS file-system description object
 216  * @lprops: LEB properties to remove
 217  * @cat: LEB category
 218  */
 219 static void remove_from_lpt_heap(struct ubifs_info *c,
 220                                  struct ubifs_lprops *lprops, int cat)
 221 {
 222         struct ubifs_lpt_heap *heap;
 223         int hpos = lprops->hpos;
 224
 225         heap = &c->lpt_heap[cat - 1];
 226         ubifs_assert(hpos >= 0 && hpos < heap->cnt);
 227         ubifs_assert(heap->arr[hpos] == lprops);
 228         heap->cnt -= 1;
 229         if (hpos < heap->cnt) {
 230                 heap->arr[hpos] = heap->arr[heap->cnt];
 231                 heap->arr[hpos]->hpos = hpos;
 232                 adjust_lpt_heap(c, heap, heap->arr[hpos], hpos, cat);
 233         }
 234         dbg_check_heap(c, heap, cat, -1);
 235 }
 236
 237 /**
 238  * lpt_heap_replace - replace lprops in a category heap.
 239  * @c: UBIFS file-system description object
 240  * @old_lprops: LEB properties to replace
 241  * @new_lprops: LEB properties with which to replace
 242  * @cat: LEB category
 243  *
 244  * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
 245  * and the lprops that the pnode contains.  When that happens, references in
 246  * the category heaps to those lprops must be updated to point to the new
 247  * lprops.  This function does that.
 248  */
 249 static void lpt_heap_replace(struct ubifs_info *c,
 250                              struct ubifs_lprops *old_lprops,
 251                              struct ubifs_lprops *new_lprops, int cat)
 252 {
 253         struct ubifs_lpt_heap *heap;
 254         int hpos = new_lprops->hpos;
 255
 256         heap = &c->lpt_heap[cat - 1];
 257         heap->arr[hpos] = new_lprops;
 258 }
 259
 260 /**
 261  * ubifs_add_to_cat - add LEB properties to a category list or heap.
 262  * @c: UBIFS file-system description object
 263  * @lprops: LEB properties to add
 264  * @cat: LEB category to which to add
 265  *
 266  * LEB properties are categorized to enable fast find operations.
 267  */
 268 void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
 269                       int cat)
 270 {
 271         switch (cat) {
 272         case LPROPS_DIRTY:
 273         case LPROPS_DIRTY_IDX:
 274         case LPROPS_FREE:
 275                 if (add_to_lpt_heap(c, lprops, cat))
 276                         break;
 277                 /* No more room on heap so make it un-categorized */
 278                 cat = LPROPS_UNCAT;
 279                 /* Fall through */
 280         case LPROPS_UNCAT:
 281                 list_add(&lprops->list, &c->uncat_list);
 282                 break;
 283         case LPROPS_EMPTY:
 284                 list_add(&lprops->list, &c->empty_list);
 285                 break;
 286         case LPROPS_FREEABLE:
 287                 list_add(&lprops->list, &c->freeable_list);
 288                 c->freeable_cnt += 1;
 289                 break;
 290         case LPROPS_FRDI_IDX:
 291                 list_add(&lprops->list, &c->frdi_idx_list);
 292                 break;
 293         default:
 294                 ubifs_assert(0);
 295         }
 296
 297         lprops->flags &= ~LPROPS_CAT_MASK;
 298         lprops->flags |= cat;
 299         c->in_a_category_cnt += 1;
 300         ubifs_assert(c->in_a_category_cnt <= c->main_lebs);
 301 }
 302
 303 /**
 304  * ubifs_remove_from_cat - remove LEB properties from a category list or heap.
 305  * @c: UBIFS file-system description object
 306  * @lprops: LEB properties to remove
 307  * @cat: LEB category from which to remove
 308  *
 309  * LEB properties are categorized to enable fast find operations.
 310  */
 311 static void ubifs_remove_from_cat(struct ubifs_info *c,
 312                                   struct ubifs_lprops *lprops, int cat)
 313 {
 314         switch (cat) {
 315         case LPROPS_DIRTY:
 316         case LPROPS_DIRTY_IDX:
 317         case LPROPS_FREE:
 318                 remove_from_lpt_heap(c, lprops, cat);
 319                 break;
 320         case LPROPS_FREEABLE:
 321                 c->freeable_cnt -= 1;
 322                 ubifs_assert(c->freeable_cnt >= 0);
 323                 /* Fall through */
 324         case LPROPS_UNCAT:
 325         case LPROPS_EMPTY:
 326         case LPROPS_FRDI_IDX:
 327                 ubifs_assert(!list_empty(&lprops->list));
 328                 list_del(&lprops->list);
 329                 break;
 330         default:
 331                 ubifs_assert(0);
 332         }
 333
 334         c->in_a_category_cnt -= 1;
 335         ubifs_assert(c->in_a_category_cnt >= 0);
 336 }
 337
 338 /**
 339  * ubifs_replace_cat - replace lprops in a category list or heap.
 340  * @c: UBIFS file-system description object
 341  * @old_lprops: LEB properties to replace
 342  * @new_lprops: LEB properties with which to replace
 343  *
 344  * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
 345  * and the lprops that the pnode contains. When that happens, references in
 346  * category lists and heaps must be replaced. This function does that.
 347  */
 348 void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
 349                        struct ubifs_lprops *new_lprops)
 350 {
 351         int cat;
 352
 353         cat = new_lprops->flags & LPROPS_CAT_MASK;
 354         switch (cat) {
 355         case LPROPS_DIRTY:
 356         case LPROPS_DIRTY_IDX:
 357         case LPROPS_FREE:
 358                 lpt_heap_replace(c, old_lprops, new_lprops, cat);
 359                 break;
 360         case LPROPS_UNCAT:
 361         case LPROPS_EMPTY:
 362         case LPROPS_FREEABLE:
 363         case LPROPS_FRDI_IDX:
 364                 list_replace(&old_lprops->list, &new_lprops->list);
 365                 break;
 366         default:
 367                 ubifs_assert(0);
 368         }
 369 }
 370
 371 /**
 372  * ubifs_ensure_cat - ensure LEB properties are categorized.
 373  * @c: UBIFS file-system description object
 374  * @lprops: LEB properties
 375  *
 376  * A LEB may have fallen off of the bottom of a heap, and ended up as
 377  * un-categorized even though it has enough space for us now. If that is the
 378  * case this function will put the LEB back onto a heap.
 379  */
 380 void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops)
 381 {
 382         int cat = lprops->flags & LPROPS_CAT_MASK;
 383
 384         if (cat != LPROPS_UNCAT)
 385                 return;
 386         cat = ubifs_categorize_lprops(c, lprops);
 387         if (cat == LPROPS_UNCAT)
 388                 return;
 389         ubifs_remove_from_cat(c, lprops, LPROPS_UNCAT);
 390         ubifs_add_to_cat(c, lprops, cat);
 391 }
 392
 393 /**
 394  * ubifs_categorize_lprops - categorize LEB properties.
 395  * @c: UBIFS file-system description object
 396  * @lprops: LEB properties to categorize
 397  *
 398  * LEB properties are categorized to enable fast find operations. This function
 399  * returns the LEB category to which the LEB properties belong. Note however
 400  * that if the LEB category is stored as a heap and the heap is full, the
 401  * LEB properties may have their category changed to %LPROPS_UNCAT.
 402  */
 403 int ubifs_categorize_lprops(const struct ubifs_info *c,
 404                             const struct ubifs_lprops *lprops)
 405 {
 406         if (lprops->flags & LPROPS_TAKEN)
 407                 return LPROPS_UNCAT;
 408
 409         if (lprops->free == c->leb_size) {
 410                 ubifs_assert(!(lprops->flags & LPROPS_INDEX));
 411                 return LPROPS_EMPTY;
 412         }
 413
 414         if (lprops->free + lprops->dirty == c->leb_size) {
 415                 if (lprops->flags & LPROPS_INDEX)
 416                         return LPROPS_FRDI_IDX;
 417                 else
 418                         return LPROPS_FREEABLE;
 419         }
 420
 421         if (lprops->flags & LPROPS_INDEX) {
 422                 if (lprops->dirty + lprops->free >= c->min_idx_node_sz)
 423                         return LPROPS_DIRTY_IDX;
 424         } else {
 425                 if (lprops->dirty >= c->dead_wm &&
 426                     lprops->dirty > lprops->free)
 427                         return LPROPS_DIRTY;
 428                 if (lprops->free > 0)
 429                         return LPROPS_FREE;
 430         }
 431
 432         return LPROPS_UNCAT;
 433 }
 434
 435 /**
 436  * change_category - change LEB properties category.
 437  * @c: UBIFS file-system description object
 438  * @lprops: LEB properties to re-categorize
 439  *
 440  * LEB properties are categorized to enable fast find operations. When the LEB
 441  * properties change they must be re-categorized.
 442  */
 443 static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops)
 444 {
 445         int old_cat = lprops->flags & LPROPS_CAT_MASK;
 446         int new_cat = ubifs_categorize_lprops(c, lprops);
 447
 448         if (old_cat == new_cat) {
 449                 struct ubifs_lpt_heap *heap;
 450
 451                 /* lprops on a heap now must be moved up or down */
 452                 if (new_cat < 1 || new_cat > LPROPS_HEAP_CNT)
 453                         return; /* Not on a heap */
 454                 heap = &c->lpt_heap[new_cat - 1];
 455                 adjust_lpt_heap(c, heap, lprops, lprops->hpos, new_cat);
 456         } else {
 457                 ubifs_remove_from_cat(c, lprops, old_cat);
 458                 ubifs_add_to_cat(c, lprops, new_cat);
 459         }
 460 }
 461
 462 /**
 463  * ubifs_calc_dark - calculate LEB dark space size.
 464  * @c: the UBIFS file-system description object
 465  * @spc: amount of free and dirty space in the LEB
 466  *
 467  * This function calculates and returns amount of dark space in an LEB which
 468  * has @spc bytes of free and dirty space.
 469  *
 470  * UBIFS is trying to account the space which might not be usable, and this
 471  * space is called "dark space". For example, if an LEB has only %512 free
 472  * bytes, it is dark space, because it cannot fit a large data node.
 473  */
 474 int ubifs_calc_dark(const struct ubifs_info *c, int spc)
 475 {
 476         ubifs_assert(!(spc & 7));
 477
 478         if (spc < c->dark_wm)
 479                 return spc;
 480
 481         /*
 482          * If we have slightly more space then the dark space watermark, we can
 483          * anyway safely assume it we'll be able to write a node of the
 484          * smallest size there.
 485          */
 486         if (spc - c->dark_wm < MIN_WRITE_SZ)
 487                 return spc - MIN_WRITE_SZ;
 488
 489         return c->dark_wm;
 490 }
 491
 492 /**
 493  * is_lprops_dirty - determine if LEB properties are dirty.
 494  * @c: the UBIFS file-system description object
 495  * @lprops: LEB properties to test
 496  */
 497 static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops)
 498 {
 499         struct ubifs_pnode *pnode;
 500         int pos;
 501
 502         pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1);
 503         pnode = (struct ubifs_pnode *)container_of(lprops - pos,
 504                                                    struct ubifs_pnode,
 505                                                    lprops[0]);
 506         return !test_bit(COW_CNODE, &pnode->flags) &&
 507                test_bit(DIRTY_CNODE, &pnode->flags);
 508 }
 509
 510 /**
 511  * ubifs_change_lp - change LEB properties.
 512  * @c: the UBIFS file-system description object
 513  * @lp: LEB properties to change
 514  * @free: new free space amount
 515  * @dirty: new dirty space amount
 516  * @flags: new flags
 517  * @idx_gc_cnt: change to the count of @idx_gc list
 518  *
 519  * This function changes LEB properties (@free, @dirty or @flag). However, the
 520  * property which has the %LPROPS_NC value is not changed. Returns a pointer to
 521  * the updated LEB properties on success and a negative error code on failure.
 522  *
 523  * Note, the LEB properties may have had to be copied (due to COW) and
 524  * consequently the pointer returned may not be the same as the pointer
 525  * passed.
 526  */
 527 const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
 528                                            const struct ubifs_lprops *lp,
 529                                            int free, int dirty, int flags,
 530                                            int idx_gc_cnt)
 531 {
 532         /*
 533          * This is the only function that is allowed to change lprops, so we
 534          * discard the "const" qualifier.
 535          */
 536         struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp;
 537
 538         dbg_lp("LEB %d, free %d, dirty %d, flags %d",
 539                lprops->lnum, free, dirty, flags);
 540
 541         ubifs_assert(mutex_is_locked(&c->lp_mutex));
 542         ubifs_assert(c->lst.empty_lebs >= 0 &&
 543                      c->lst.empty_lebs <= c->main_lebs);
 544         ubifs_assert(c->freeable_cnt >= 0);
 545         ubifs_assert(c->freeable_cnt <= c->main_lebs);
 546         ubifs_assert(c->lst.taken_empty_lebs >= 0);
 547         ubifs_assert(c->lst.taken_empty_lebs <= c->lst.empty_lebs);
 548         ubifs_assert(!(c->lst.total_free & 7) && !(c->lst.total_dirty & 7));
 549         ubifs_assert(!(c->lst.total_dead & 7) && !(c->lst.total_dark & 7));
 550         ubifs_assert(!(c->lst.total_used & 7));
 551         ubifs_assert(free == LPROPS_NC || free >= 0);
 552         ubifs_assert(dirty == LPROPS_NC || dirty >= 0);
 553
 554         if (!is_lprops_dirty(c, lprops)) {
 555                 lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum);
 556                 if (IS_ERR(lprops))
 557                         return lprops;
 558         } else
 559                 ubifs_assert(lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum));
 560
 561         ubifs_assert(!(lprops->free & 7) && !(lprops->dirty & 7));
 562
 563         spin_lock(&c->space_lock);
 564         if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
 565                 c->lst.taken_empty_lebs -= 1;
 566
 567         if (!(lprops->flags & LPROPS_INDEX)) {
 568                 int old_spc;
 569
 570                 old_spc = lprops->free + lprops->dirty;
 571                 if (old_spc < c->dead_wm)
 572                         c->lst.total_dead -= old_spc;
 573                 else
 574                         c->lst.total_dark -= ubifs_calc_dark(c, old_spc);
 575
 576                 c->lst.total_used -= c->leb_size - old_spc;
 577         }
 578
 579         if (free != LPROPS_NC) {
 580                 free = ALIGN(free, 8);
 581                 c->lst.total_free += free - lprops->free;
 582
 583                 /* Increase or decrease empty LEBs counter if needed */
 584                 if (free == c->leb_size) {
 585                         if (lprops->free != c->leb_size)
 586                                 c->lst.empty_lebs += 1;
 587                 } else if (lprops->free == c->leb_size)
 588                         c->lst.empty_lebs -= 1;
 589                 lprops->free = free;
 590         }
 591
 592         if (dirty != LPROPS_NC) {
 593                 dirty = ALIGN(dirty, 8);
 594                 c->lst.total_dirty += dirty - lprops->dirty;
 595                 lprops->dirty = dirty;
 596         }
 597
 598         if (flags != LPROPS_NC) {
 599                 /* Take care about indexing LEBs counter if needed */
 600                 if ((lprops->flags & LPROPS_INDEX)) {
 601                         if (!(flags & LPROPS_INDEX))
 602                                 c->lst.idx_lebs -= 1;
 603                 } else if (flags & LPROPS_INDEX)
 604                         c->lst.idx_lebs += 1;
 605                 lprops->flags = flags;
 606         }
 607
 608         if (!(lprops->flags & LPROPS_INDEX)) {
 609                 int new_spc;
 610
 611                 new_spc = lprops->free + lprops->dirty;
 612                 if (new_spc < c->dead_wm)
 613                         c->lst.total_dead += new_spc;
 614                 else
 615                         c->lst.total_dark += ubifs_calc_dark(c, new_spc);
 616
 617                 c->lst.total_used += c->leb_size - new_spc;
 618         }
 619
 620         if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
 621                 c->lst.taken_empty_lebs += 1;
 622
 623         change_category(c, lprops);
 624         c->idx_gc_cnt += idx_gc_cnt;
 625         spin_unlock(&c->space_lock);
 626         return lprops;
 627 }
 628
 629 /**
 630  * ubifs_get_lp_stats - get lprops statistics.
 631  * @c: UBIFS file-system description object
 632  * @st: return statistics
 633  */
 634 void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst)
 635 {
 636         spin_lock(&c->space_lock);
 637         memcpy(lst, &c->lst, sizeof(struct ubifs_lp_stats));
 638         spin_unlock(&c->space_lock);
 639 }
 640
 641 /**
 642  * ubifs_change_one_lp - change LEB properties.
 643  * @c: the UBIFS file-system description object
 644  * @lnum: LEB to change properties for
 645  * @free: amount of free space
 646  * @dirty: amount of dirty space
 647  * @flags_set: flags to set
 648  * @flags_clean: flags to clean
 649  * @idx_gc_cnt: change to the count of idx_gc list
 650  *
 651  * This function changes properties of LEB @lnum. It is a helper wrapper over
 652  * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the
 653  * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and
 654  * a negative error code in case of failure.
 655  */
 656 int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
 657                         int flags_set, int flags_clean, int idx_gc_cnt)
 658 {
 659         int err = 0, flags;
 660         const struct ubifs_lprops *lp;
 661
 662         ubifs_get_lprops(c);
 663
 664         lp = ubifs_lpt_lookup_dirty(c, lnum);
 665         if (IS_ERR(lp)) {
 666                 err = PTR_ERR(lp);
 667                 goto out;
 668         }
 669
 670         flags = (lp->flags | flags_set) & ~flags_clean;
 671         lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt);
 672         if (IS_ERR(lp))
 673                 err = PTR_ERR(lp);
 674
 675 out:
 676         ubifs_release_lprops(c);
 677         if (err)
 678                 ubifs_err("cannot change properties of LEB %d, error %d",
 679                           lnum, err);
 680         return err;
 681 }
 682
 683 /**
 684  * ubifs_update_one_lp - update LEB properties.
 685  * @c: the UBIFS file-system description object
 686  * @lnum: LEB to change properties for
 687  * @free: amount of free space
 688  * @dirty: amount of dirty space to add
 689  * @flags_set: flags to set
 690  * @flags_clean: flags to clean
 691  *
 692  * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to
 693  * current dirty space, not substitutes it.
 694  */
 695 int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
 696                         int flags_set, int flags_clean)
 697 {
 698         int err = 0, flags;
 699         const struct ubifs_lprops *lp;
 700
 701         ubifs_get_lprops(c);
 702
 703         lp = ubifs_lpt_lookup_dirty(c, lnum);
 704         if (IS_ERR(lp)) {
 705                 err = PTR_ERR(lp);
 706                 goto out;
 707         }
 708
 709         flags = (lp->flags | flags_set) & ~flags_clean;
 710         lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0);
 711         if (IS_ERR(lp))
 712                 err = PTR_ERR(lp);
 713
 714 out:
 715         ubifs_release_lprops(c);
 716         if (err)
 717                 ubifs_err("cannot update properties of LEB %d, error %d",
 718                           lnum, err);
 719         return err;
 720 }
 721
 722 /**
 723  * ubifs_read_one_lp - read LEB properties.
 724  * @c: the UBIFS file-system description object
 725  * @lnum: LEB to read properties for
 726  * @lp: where to store read properties
 727  *
 728  * This helper function reads properties of a LEB @lnum and stores them in @lp.
 729  * Returns zero in case of success and a negative error code in case of
 730  * failure.
 731  */
 732 int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp)
 733 {
 734         int err = 0;
 735         const struct ubifs_lprops *lpp;
 736
 737         ubifs_get_lprops(c);
 738
 739         lpp = ubifs_lpt_lookup(c, lnum);
 740         if (IS_ERR(lpp)) {
 741                 err = PTR_ERR(lpp);
 742                 ubifs_err("cannot read properties of LEB %d, error %d",
 743                           lnum, err);
 744                 goto out;
 745         }
 746
 747         memcpy(lp, lpp, sizeof(struct ubifs_lprops));
 748
 749 out:
 750         ubifs_release_lprops(c);
 751         return err;
 752 }
 753
 754 /**
 755  * ubifs_fast_find_free - try to find a LEB with free space quickly.
 756  * @c: the UBIFS file-system description object
 757  *
 758  * This function returns LEB properties for a LEB with free space or %NULL if
 759  * the function is unable to find a LEB quickly.
 760  */
 761 const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c)
 762 {
 763         struct ubifs_lprops *lprops;
 764         struct ubifs_lpt_heap *heap;
 765
 766         ubifs_assert(mutex_is_locked(&c->lp_mutex));
 767
 768         heap = &c->lpt_heap[LPROPS_FREE - 1];
 769         if (heap->cnt == 0)
 770                 return NULL;
 771
 772         lprops = heap->arr[0];
 773         ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
 774         ubifs_assert(!(lprops->flags & LPROPS_INDEX));
 775         return lprops;
 776 }
 777
 778 /**
 779  * ubifs_fast_find_empty - try to find an empty LEB quickly.
 780  * @c: the UBIFS file-system description object
 781  *
 782  * This function returns LEB properties for an empty LEB or %NULL if the
 783  * function is unable to find an empty LEB quickly.
 784  */
 785 const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c)
 786 {
 787         struct ubifs_lprops *lprops;
 788
 789         ubifs_assert(mutex_is_locked(&c->lp_mutex));
 790
 791         if (list_empty(&c->empty_list))
 792                 return NULL;
 793
 794         lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list);
 795         ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
 796         ubifs_assert(!(lprops->flags & LPROPS_INDEX));
 797         ubifs_assert(lprops->free == c->leb_size);
 798         return lprops;
 799 }
 800
 801 /**
 802  * ubifs_fast_find_freeable - try to find a freeable LEB quickly.
 803  * @c: the UBIFS file-system description object
 804  *
 805  * This function returns LEB properties for a freeable LEB or %NULL if the
 806  * function is unable to find a freeable LEB quickly.
 807  */
 808 const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c)
 809 {
 810         struct ubifs_lprops *lprops;
 811
 812         ubifs_assert(mutex_is_locked(&c->lp_mutex));
 813
 814         if (list_empty(&c->freeable_list))
 815                 return NULL;
 816
 817         lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list);
 818         ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
 819         ubifs_assert(!(lprops->flags & LPROPS_INDEX));
 820         ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
 821         ubifs_assert(c->freeable_cnt > 0);
 822         return lprops;
 823 }
 824
 825 /**
 826  * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly.
 827  * @c: the UBIFS file-system description object
 828  *
 829  * This function returns LEB properties for a freeable index LEB or %NULL if the
 830  * function is unable to find a freeable index LEB quickly.
 831  */
 832 const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c)
 833 {
 834         struct ubifs_lprops *lprops;
 835
 836         ubifs_assert(mutex_is_locked(&c->lp_mutex));
 837
 838         if (list_empty(&c->frdi_idx_list))
 839                 return NULL;
 840
 841         lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list);
 842         ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
 843         ubifs_assert((lprops->flags & LPROPS_INDEX));
 844         ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
 845         return lprops;
 846 }
 847
 848 /*
 849  * Everything below is related to debugging.
 850  */
 851
 852 /**
 853  * dbg_check_cats - check category heaps and lists.
 854  * @c: UBIFS file-system description object
 855  *
 856  * This function returns %0 on success and a negative error code on failure.
 857  */
 858 int dbg_check_cats(struct ubifs_info *c)
 859 {
 860         struct ubifs_lprops *lprops;
 861         struct list_head *pos;
 862         int i, cat;
 863
 864         if (!dbg_is_chk_gen(c) && !dbg_is_chk_lprops(c))
 865                 return 0;
 866
 867         list_for_each_entry(lprops, &c->empty_list, list) {
 868                 if (lprops->free != c->leb_size) {
 869                         ubifs_err("non-empty LEB %d on empty list (free %d dirty %d flags %d)",
 870                                   lprops->lnum, lprops->free, lprops->dirty,
 871                                   lprops->flags);
 872                         return -EINVAL;
 873                 }
 874                 if (lprops->flags & LPROPS_TAKEN) {
 875                         ubifs_err("taken LEB %d on empty list (free %d dirty %d flags %d)",
 876                                   lprops->lnum, lprops->free, lprops->dirty,
 877                                   lprops->flags);
 878                         return -EINVAL;
 879                 }
 880         }
 881
 882         i = 0;
 883         list_for_each_entry(lprops, &c->freeable_list, list) {
 884                 if (lprops->free + lprops->dirty != c->leb_size) {
 885                         ubifs_err("non-freeable LEB %d on freeable list (free %d dirty %d flags %d)",
 886                                   lprops->lnum, lprops->free, lprops->dirty,
 887                                   lprops->flags);
 888                         return -EINVAL;
 889                 }
 890                 if (lprops->flags & LPROPS_TAKEN) {
 891                         ubifs_err("taken LEB %d on freeable list (free %d dirty %d flags %d)",
 892                                   lprops->lnum, lprops->free, lprops->dirty,
 893                                   lprops->flags);
 894                         return -EINVAL;
 895                 }
 896                 i += 1;
 897         }
 898         if (i != c->freeable_cnt) {
 899                 ubifs_err("freeable list count %d expected %d", i,
 900                           c->freeable_cnt);
 901                 return -EINVAL;
 902         }
 903
 904         i = 0;
 905         list_for_each(pos, &c->idx_gc)
 906                 i += 1;
 907         if (i != c->idx_gc_cnt) {
 908                 ubifs_err("idx_gc list count %d expected %d", i,
 909                           c->idx_gc_cnt);
 910                 return -EINVAL;
 911         }
 912
 913         list_for_each_entry(lprops, &c->frdi_idx_list, list) {
 914                 if (lprops->free + lprops->dirty != c->leb_size) {
 915                         ubifs_err("non-freeable LEB %d on frdi_idx list (free %d dirty %d flags %d)",
 916                                   lprops->lnum, lprops->free, lprops->dirty,
 917                                   lprops->flags);
 918                         return -EINVAL;
 919                 }
 920                 if (lprops->flags & LPROPS_TAKEN) {
 921                         ubifs_err("taken LEB %d on frdi_idx list (free %d dirty %d flags %d)",
 922                                   lprops->lnum, lprops->free, lprops->dirty,
 923                                   lprops->flags);
 924                         return -EINVAL;
 925                 }
 926                 if (!(lprops->flags & LPROPS_INDEX)) {
 927                         ubifs_err("non-index LEB %d on frdi_idx list (free %d dirty %d flags %d)",
 928                                   lprops->lnum, lprops->free, lprops->dirty,
 929                                   lprops->flags);
 930                         return -EINVAL;
 931                 }
 932         }
 933
 934         for (cat = 1; cat <= LPROPS_HEAP_CNT; cat++) {
 935                 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
 936
 937                 for (i = 0; i < heap->cnt; i++) {
 938                         lprops = heap->arr[i];
 939                         if (!lprops) {
 940                                 ubifs_err("null ptr in LPT heap cat %d", cat);
 941                                 return -EINVAL;
 942                         }
 943                         if (lprops->hpos != i) {
 944                                 ubifs_err("bad ptr in LPT heap cat %d", cat);
 945                                 return -EINVAL;
 946                         }
 947                         if (lprops->flags & LPROPS_TAKEN) {
 948                                 ubifs_err("taken LEB in LPT heap cat %d", cat);
 949                                 return -EINVAL;
 950                         }
 951                 }
 952         }
 953
 954         return 0;
 955 }
 956
 957 void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
 958                     int add_pos)
 959 {
 960         int i = 0, j, err = 0;
 961
 962         if (!dbg_is_chk_gen(c) && !dbg_is_chk_lprops(c))
 963                 return;
 964
 965         for (i = 0; i < heap->cnt; i++) {
 966                 struct ubifs_lprops *lprops = heap->arr[i];
 967                 struct ubifs_lprops *lp;
 968
 969                 if (i != add_pos)
 970                         if ((lprops->flags & LPROPS_CAT_MASK) != cat) {
 971                                 err = 1;
 972                                 goto out;
 973                         }
 974                 if (lprops->hpos != i) {
 975                         err = 2;
 976                         goto out;
 977                 }
 978                 lp = ubifs_lpt_lookup(c, lprops->lnum);
 979                 if (IS_ERR(lp)) {
 980                         err = 3;
 981                         goto out;
 982                 }
 983                 if (lprops != lp) {
 984                         ubifs_err("lprops %zx lp %zx lprops->lnum %d lp->lnum %d",
 985                                   (size_t)lprops, (size_t)lp, lprops->lnum,
 986                                   lp->lnum);
 987                         err = 4;
 988                         goto out;
 989                 }
 990                 for (j = 0; j < i; j++) {
 991                         lp = heap->arr[j];
 992                         if (lp == lprops) {
 993                                 err = 5;
 994                                 goto out;
 995                         }
 996                         if (lp->lnum == lprops->lnum) {
 997                                 err = 6;
 998                                 goto out;
 999                         }
1000                 }
1001         }
1002 out:
1003         if (err) {
1004                 ubifs_err("failed cat %d hpos %d err %d", cat, i, err);
1005                 dump_stack();
1006                 ubifs_dump_heap(c, heap, cat);
1007         }
1008 }
1009
1010 /**
1011  * scan_check_cb - scan callback.
1012  * @c: the UBIFS file-system description object
1013  * @lp: LEB properties to scan
1014  * @in_tree: whether the LEB properties are in main memory
1015  * @lst: lprops statistics to update
1016  *
1017  * This function returns a code that indicates whether the scan should continue
1018  * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
1019  * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
1020  * (%LPT_SCAN_STOP).
1021  */
1022 static int scan_check_cb(struct ubifs_info *c,
1023                          const struct ubifs_lprops *lp, int in_tree,
1024                          struct ubifs_lp_stats *lst)
1025 {
1026         struct ubifs_scan_leb *sleb;
1027         struct ubifs_scan_node *snod;
1028         int cat, lnum = lp->lnum, is_idx = 0, used = 0, freef, dirty, ret;
1029         void *buf = NULL;
1030
1031         cat = lp->flags & LPROPS_CAT_MASK;
1032         if (cat != LPROPS_UNCAT) {
1033                 cat = ubifs_categorize_lprops(c, lp);
1034                 if (cat != (lp->flags & LPROPS_CAT_MASK)) {
1035                         ubifs_err("bad LEB category %d expected %d",
1036                                   (lp->flags & LPROPS_CAT_MASK), cat);
1037                         return -EINVAL;
1038                 }
1039         }
1040
1041         /* Check lp is on its category list (if it has one) */
1042         if (in_tree) {
1043                 struct list_head *list = NULL;
1044
1045                 switch (cat) {
1046                 case LPROPS_EMPTY:
1047                         list = &c->empty_list;
1048                         break;
1049                 case LPROPS_FREEABLE:
1050                         list = &c->freeable_list;
1051                         break;
1052                 case LPROPS_FRDI_IDX:
1053                         list = &c->frdi_idx_list;
1054                         break;
1055                 case LPROPS_UNCAT:
1056                         list = &c->uncat_list;
1057                         break;
1058                 }
1059                 if (list) {
1060                         struct ubifs_lprops *lprops;
1061                         int found = 0;
1062
1063                         list_for_each_entry(lprops, list, list) {
1064                                 if (lprops == lp) {
1065                                         found = 1;
1066                                         break;
1067                                 }
1068                         }
1069                         if (!found) {
1070                                 ubifs_err("bad LPT list (category %d)", cat);
1071                                 return -EINVAL;
1072                         }
1073                 }
1074         }
1075
1076         /* Check lp is on its category heap (if it has one) */
1077         if (in_tree && cat > 0 && cat <= LPROPS_HEAP_CNT) {
1078                 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
1079
1080                 if ((lp->hpos != -1 && heap->arr[lp->hpos]->lnum != lnum) ||
1081                     lp != heap->arr[lp->hpos]) {
1082                         ubifs_err("bad LPT heap (category %d)", cat);
1083                         return -EINVAL;
1084                 }
1085         }
1086
1087         buf = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
1088         if (!buf)
1089                 return -ENOMEM;
1090
1091         /*
1092          * After an unclean unmount, empty and freeable LEBs
1093          * may contain garbage - do not scan them.
1094          */
1095         if (lp->free == c->leb_size) {
1096                 lst->empty_lebs += 1;
1097                 lst->total_free += c->leb_size;
1098                 lst->total_dark += ubifs_calc_dark(c, c->leb_size);
1099                 return LPT_SCAN_CONTINUE;
1100         }
1101         if (lp->free + lp->dirty == c->leb_size &&
1102             !(lp->flags & LPROPS_INDEX)) {
1103                 lst->total_free  += lp->free;
1104                 lst->total_dirty += lp->dirty;
1105                 lst->total_dark  +=  ubifs_calc_dark(c, c->leb_size);
1106                 return LPT_SCAN_CONTINUE;
1107         }
1108
1109         sleb = ubifs_scan(c, lnum, 0, buf, 0);
1110         if (IS_ERR(sleb)) {
1111                 ret = PTR_ERR(sleb);
1112                 if (ret == -EUCLEAN) {
1113                         ubifs_dump_lprops(c);
1114                         ubifs_dump_budg(c, &c->bi);
1115                 }
1116                 goto out;
1117         }
1118
1119         is_idx = -1;
1120         list_for_each_entry(snod, &sleb->nodes, list) {
1121                 int found, level = 0;
1122
1123                 cond_resched();
1124
1125                 if (is_idx == -1)
1126                         is_idx = (snod->type == UBIFS_IDX_NODE) ? 1 : 0;
1127
1128                 if (is_idx && snod->type != UBIFS_IDX_NODE) {
1129                         ubifs_err("indexing node in data LEB %d:%d",
1130                                   lnum, snod->offs);
1131                         goto out_destroy;
1132                 }
1133
1134                 if (snod->type == UBIFS_IDX_NODE) {
1135                         struct ubifs_idx_node *idx = snod->node;
1136
1137                         key_read(c, ubifs_idx_key(c, idx), &snod->key);
1138                         level = le16_to_cpu(idx->level);
1139                 }
1140
1141                 found = ubifs_tnc_has_node(c, &snod->key, level, lnum,
1142                                            snod->offs, is_idx);
1143                 if (found) {
1144                         if (found < 0)
1145                                 goto out_destroy;
1146                         used += ALIGN(snod->len, 8);
1147                 }
1148         }
1149
1150         freef = c->leb_size - sleb->endpt;
1151         dirty = sleb->endpt - used;
1152
1153         if (freef > c->leb_size || freef < 0 || dirty > c->leb_size ||
1154             dirty < 0) {
1155                 ubifs_err("bad calculated accounting for LEB %d: free %d, dirty %d",
1156                           lnum, freef, dirty);
1157                 goto out_destroy;
1158         }
1159
1160         if (lp->free + lp->dirty == c->leb_size &&
1161             freef + dirty == c->leb_size)
1162                 if ((is_idx && !(lp->flags & LPROPS_INDEX)) ||
1163                     (!is_idx && freef == c->leb_size) ||
1164                     lp->free == c->leb_size) {
1165                         /*
1166                          * Empty or freeable LEBs could contain index
1167                          * nodes from an uncompleted commit due to an
1168                          * unclean unmount. Or they could be empty for
1169                          * the same reason. Or it may simply not have been
1170                          * unmapped.
1171                          */
1172                         freef = lp->free;
1173                         dirty = lp->dirty;
1174                         is_idx = 0;
1175                     }
1176
1177         if (is_idx && lp->free + lp->dirty == freef + dirty &&
1178             lnum != c->ihead_lnum) {
1179                 /*
1180                  * After an unclean unmount, an index LEB could have a different
1181                  * amount of free space than the value recorded by lprops. That
1182                  * is because the in-the-gaps method may use free space or
1183                  * create free space (as a side-effect of using ubi_leb_change
1184                  * and not writing the whole LEB). The incorrect free space
1185                  * value is not a problem because the index is only ever
1186                  * allocated empty LEBs, so there will never be an attempt to
1187                  * write to the free space at the end of an index LEB - except
1188                  * by the in-the-gaps method for which it is not a problem.
1189                  */
1190                 freef = lp->free;
1191                 dirty = lp->dirty;
1192         }
1193
1194         if (lp->free != freef || lp->dirty != dirty)
1195                 goto out_print;
1196
1197         if (is_idx && !(lp->flags & LPROPS_INDEX)) {
1198                 if (freef == c->leb_size)
1199                         /* Free but not unmapped LEB, it's fine */
1200                         is_idx = 0;
1201                 else {
1202                         ubifs_err("indexing node without indexing 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 (freef == 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 - freef - dirty;
1220         lst->total_free += freef;
1221         lst->total_dirty += dirty;
1222
1223         if (!(lp->flags & LPROPS_INDEX)) {
1224                 int spc = freef + 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
1236 out_print:
1237         ubifs_err("bad accounting of LEB %d: free %d, dirty %d flags %#x, should be free %d, dirty %d",
1238                   lnum, lp->free, lp->dirty, lp->flags, freef, dirty);
1239         ubifs_dump_leb(c, lnum);
1240 out_destroy:
1241         ubifs_scan_destroy(sleb);
1242         ret = -EINVAL;
1243 out:
1244         vfree(buf);
1245         return ret;
1246 }
1247
1248 /**
1249  * dbg_check_lprops - check all LEB properties.
1250  * @c: UBIFS file-system description object
1251  *
1252  * This function checks all LEB properties and makes sure they are all correct.
1253  * It returns zero if everything is fine, %-EINVAL if there is an inconsistency
1254  * and other negative error codes in case of other errors. This function is
1255  * called while the file system is locked (because of commit start), so no
1256  * additional locking is required. Note that locking the LPT mutex would cause
1257  * a circular lock dependency with the TNC mutex.
1258  */
1259 int dbg_check_lprops(struct ubifs_info *c)
1260 {
1261         int i, err;
1262         struct ubifs_lp_stats lst;
1263
1264         if (!dbg_is_chk_lprops(c))
1265                 return 0;
1266
1267         /*
1268          * As we are going to scan the media, the write buffers have to be
1269          * synchronized.
1270          */
1271         for (i = 0; i < c->jhead_cnt; i++) {
1272                 err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
1273                 if (err)
1274                         return err;
1275         }
1276
1277         memset(&lst, 0, sizeof(struct ubifs_lp_stats));
1278         err = ubifs_lpt_scan_nolock(c, c->main_first, c->leb_cnt - 1,
1279                                     (ubifs_lpt_scan_callback)scan_check_cb,
1280                                     &lst);
1281         if (err && err != -ENOSPC)
1282                 goto out;
1283
1284         if (lst.empty_lebs != c->lst.empty_lebs ||
1285             lst.idx_lebs != c->lst.idx_lebs ||
1286             lst.total_free != c->lst.total_free ||
1287             lst.total_dirty != c->lst.total_dirty ||
1288             lst.total_used != c->lst.total_used) {
1289                 ubifs_err("bad overall accounting");
1290                 ubifs_err("calculated: empty_lebs %d, idx_lebs %d, total_free %lld, total_dirty %lld, total_used %lld",
1291                           lst.empty_lebs, lst.idx_lebs, lst.total_free,
1292                           lst.total_dirty, lst.total_used);
1293                 ubifs_err("read from lprops: empty_lebs %d, idx_lebs %d, total_free %lld, total_dirty %lld, total_used %lld",
1294                           c->lst.empty_lebs, c->lst.idx_lebs, c->lst.total_free,
1295                           c->lst.total_dirty, c->lst.total_used);
1296                 err = -EINVAL;
1297                 goto out;
1298         }
1299
1300         if (lst.total_dead != c->lst.total_dead ||
1301             lst.total_dark != c->lst.total_dark) {
1302                 ubifs_err("bad dead/dark space accounting");
1303                 ubifs_err("calculated: total_dead %lld, total_dark %lld",
1304                           lst.total_dead, lst.total_dark);
1305                 ubifs_err("read from lprops: total_dead %lld, total_dark %lld",
1306                           c->lst.total_dead, c->lst.total_dark);
1307                 err = -EINVAL;
1308                 goto out;
1309         }
1310
1311         err = dbg_check_cats(c);
1312 out:
1313         return err;
1314 }