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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * This file is part of UBIFS.
4 *
5 * Copyright (C) 2006-2008 Nokia Corporation.
6 *
7 * Authors: Adrian Hunter
8 * Artem Bityutskiy (Битюцкий Артём)
9 */
10
11/*
12 * This file implements the functions that access LEB properties and their
13 * categories. LEBs are categorized based on the needs of UBIFS, and the
14 * categories are stored as either heaps or lists to provide a fast way of
15 * finding a LEB in a particular category. For example, UBIFS may need to find
16 * an empty LEB for the journal, or a very dirty LEB for garbage collection.
17 */
18
19#include "ubifs.h"
20
21/**
22 * get_heap_comp_val - get the LEB properties value for heap comparisons.
23 * @lprops: LEB properties
24 * @cat: LEB category
25 */
26static int get_heap_comp_val(struct ubifs_lprops *lprops, int cat)
27{
28 switch (cat) {
29 case LPROPS_FREE:
30 return lprops->free;
31 case LPROPS_DIRTY_IDX:
32 return lprops->free + lprops->dirty;
33 default:
34 return lprops->dirty;
35 }
36}
37
38/**
39 * move_up_lpt_heap - move a new heap entry up as far as possible.
40 * @c: UBIFS file-system description object
41 * @heap: LEB category heap
42 * @lprops: LEB properties to move
43 * @cat: LEB category
44 *
45 * New entries to a heap are added at the bottom and then moved up until the
46 * parent's value is greater. In the case of LPT's category heaps, the value
47 * is either the amount of free space or the amount of dirty space, depending
48 * on the category.
49 */
50static void move_up_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
51 struct ubifs_lprops *lprops, int cat)
52{
53 int val1, val2, hpos;
54
55 hpos = lprops->hpos;
56 if (!hpos)
57 return; /* Already top of the heap */
58 val1 = get_heap_comp_val(lprops, cat);
59 /* Compare to parent and, if greater, move up the heap */
60 do {
61 int ppos = (hpos - 1) / 2;
62
63 val2 = get_heap_comp_val(heap->arr[ppos], cat);
64 if (val2 >= val1)
65 return;
66 /* Greater than parent so move up */
67 heap->arr[ppos]->hpos = hpos;
68 heap->arr[hpos] = heap->arr[ppos];
69 heap->arr[ppos] = lprops;
70 lprops->hpos = ppos;
71 hpos = ppos;
72 } while (hpos);
73}
74
75/**
76 * adjust_lpt_heap - move a changed heap entry up or down the heap.
77 * @c: UBIFS file-system description object
78 * @heap: LEB category heap
79 * @lprops: LEB properties to move
80 * @hpos: heap position of @lprops
81 * @cat: LEB category
82 *
83 * Changed entries in a heap are moved up or down until the parent's value is
84 * greater. In the case of LPT's category heaps, the value is either the amount
85 * of free space or the amount of dirty space, depending on the category.
86 */
87static void adjust_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
88 struct ubifs_lprops *lprops, int hpos, int cat)
89{
90 int val1, val2, val3, cpos;
91
92 val1 = get_heap_comp_val(lprops, cat);
93 /* Compare to parent and, if greater than parent, move up the heap */
94 if (hpos) {
95 int ppos = (hpos - 1) / 2;
96
97 val2 = get_heap_comp_val(heap->arr[ppos], cat);
98 if (val1 > val2) {
99 /* Greater than parent so move up */
100 while (1) {
101 heap->arr[ppos]->hpos = hpos;
102 heap->arr[hpos] = heap->arr[ppos];
103 heap->arr[ppos] = lprops;
104 lprops->hpos = ppos;
105 hpos = ppos;
106 if (!hpos)
107 return;
108 ppos = (hpos - 1) / 2;
109 val2 = get_heap_comp_val(heap->arr[ppos], cat);
110 if (val1 <= val2)
111 return;
112 /* Still greater than parent so keep going */
113 }
114 }
115 }
116
117 /* Not greater than parent, so compare to children */
118 while (1) {
119 /* Compare to left child */
120 cpos = hpos * 2 + 1;
121 if (cpos >= heap->cnt)
122 return;
123 val2 = get_heap_comp_val(heap->arr[cpos], cat);
124 if (val1 < val2) {
125 /* Less than left child, so promote biggest child */
126 if (cpos + 1 < heap->cnt) {
127 val3 = get_heap_comp_val(heap->arr[cpos + 1],
128 cat);
129 if (val3 > val2)
130 cpos += 1; /* Right child is bigger */
131 }
132 heap->arr[cpos]->hpos = hpos;
133 heap->arr[hpos] = heap->arr[cpos];
134 heap->arr[cpos] = lprops;
135 lprops->hpos = cpos;
136 hpos = cpos;
137 continue;
138 }
139 /* Compare to right child */
140 cpos += 1;
141 if (cpos >= heap->cnt)
142 return;
143 val3 = get_heap_comp_val(heap->arr[cpos], cat);
144 if (val1 < val3) {
145 /* Less than right child, so promote right child */
146 heap->arr[cpos]->hpos = hpos;
147 heap->arr[hpos] = heap->arr[cpos];
148 heap->arr[cpos] = lprops;
149 lprops->hpos = cpos;
150 hpos = cpos;
151 continue;
152 }
153 return;
154 }
155}
156
157/**
158 * add_to_lpt_heap - add LEB properties to a LEB category heap.
159 * @c: UBIFS file-system description object
160 * @lprops: LEB properties to add
161 * @cat: LEB category
162 *
163 * This function returns %1 if @lprops is added to the heap for LEB category
164 * @cat, otherwise %0 is returned because the heap is full.
165 */
166static int add_to_lpt_heap(struct ubifs_info *c, struct ubifs_lprops *lprops,
167 int cat)
168{
169 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
170
171 if (heap->cnt >= heap->max_cnt) {
172 const int b = LPT_HEAP_SZ / 2 - 1;
173 int cpos, val1, val2;
174
175 /* Compare to some other LEB on the bottom of heap */
176 /* Pick a position kind of randomly */
177 cpos = (((size_t)lprops >> 4) & b) + b;
178 ubifs_assert(c, cpos >= b);
179 ubifs_assert(c, cpos < LPT_HEAP_SZ);
180 ubifs_assert(c, cpos < heap->cnt);
181
182 val1 = get_heap_comp_val(lprops, cat);
183 val2 = get_heap_comp_val(heap->arr[cpos], cat);
184 if (val1 > val2) {
185 struct ubifs_lprops *lp;
186
187 lp = heap->arr[cpos];
188 lp->flags &= ~LPROPS_CAT_MASK;
189 lp->flags |= LPROPS_UNCAT;
190 list_add(&lp->list, &c->uncat_list);
191 lprops->hpos = cpos;
192 heap->arr[cpos] = lprops;
193 move_up_lpt_heap(c, heap, lprops, cat);
194 dbg_check_heap(c, heap, cat, lprops->hpos);
195 return 1; /* Added to heap */
196 }
197 dbg_check_heap(c, heap, cat, -1);
198 return 0; /* Not added to heap */
199 } else {
200 lprops->hpos = heap->cnt++;
201 heap->arr[lprops->hpos] = lprops;
202 move_up_lpt_heap(c, heap, lprops, cat);
203 dbg_check_heap(c, heap, cat, lprops->hpos);
204 return 1; /* Added to heap */
205 }
206}
207
208/**
209 * remove_from_lpt_heap - remove LEB properties from a LEB category heap.
210 * @c: UBIFS file-system description object
211 * @lprops: LEB properties to remove
212 * @cat: LEB category
213 */
214static void remove_from_lpt_heap(struct ubifs_info *c,
215 struct ubifs_lprops *lprops, int cat)
216{
217 struct ubifs_lpt_heap *heap;
218 int hpos = lprops->hpos;
219
220 heap = &c->lpt_heap[cat - 1];
221 ubifs_assert(c, hpos >= 0 && hpos < heap->cnt);
222 ubifs_assert(c, heap->arr[hpos] == lprops);
223 heap->cnt -= 1;
224 if (hpos < heap->cnt) {
225 heap->arr[hpos] = heap->arr[heap->cnt];
226 heap->arr[hpos]->hpos = hpos;
227 adjust_lpt_heap(c, heap, heap->arr[hpos], hpos, cat);
228 }
229 dbg_check_heap(c, heap, cat, -1);
230}
231
232/**
233 * lpt_heap_replace - replace lprops in a category heap.
234 * @c: UBIFS file-system description object
235 * @new_lprops: LEB properties with which to replace
236 * @cat: LEB category
237 *
238 * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
239 * and the lprops that the pnode contains. When that happens, references in
240 * the category heaps to those lprops must be updated to point to the new
241 * lprops. This function does that.
242 */
243static void lpt_heap_replace(struct ubifs_info *c,
244 struct ubifs_lprops *new_lprops, int cat)
245{
246 struct ubifs_lpt_heap *heap;
247 int hpos = new_lprops->hpos;
248
249 heap = &c->lpt_heap[cat - 1];
250 heap->arr[hpos] = new_lprops;
251}
252
253/**
254 * ubifs_add_to_cat - add LEB properties to a category list or heap.
255 * @c: UBIFS file-system description object
256 * @lprops: LEB properties to add
257 * @cat: LEB category to which to add
258 *
259 * LEB properties are categorized to enable fast find operations.
260 */
261void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
262 int cat)
263{
264 switch (cat) {
265 case LPROPS_DIRTY:
266 case LPROPS_DIRTY_IDX:
267 case LPROPS_FREE:
268 if (add_to_lpt_heap(c, lprops, cat))
269 break;
270 /* No more room on heap so make it un-categorized */
271 cat = LPROPS_UNCAT;
272 /* Fall through */
273 case LPROPS_UNCAT:
274 list_add(&lprops->list, &c->uncat_list);
275 break;
276 case LPROPS_EMPTY:
277 list_add(&lprops->list, &c->empty_list);
278 break;
279 case LPROPS_FREEABLE:
280 list_add(&lprops->list, &c->freeable_list);
281 c->freeable_cnt += 1;
282 break;
283 case LPROPS_FRDI_IDX:
284 list_add(&lprops->list, &c->frdi_idx_list);
285 break;
286 default:
287 ubifs_assert(c, 0);
288 }
289
290 lprops->flags &= ~LPROPS_CAT_MASK;
291 lprops->flags |= cat;
292 c->in_a_category_cnt += 1;
293 ubifs_assert(c, c->in_a_category_cnt <= c->main_lebs);
294}
295
296/**
297 * ubifs_remove_from_cat - remove LEB properties from a category list or heap.
298 * @c: UBIFS file-system description object
299 * @lprops: LEB properties to remove
300 * @cat: LEB category from which to remove
301 *
302 * LEB properties are categorized to enable fast find operations.
303 */
304static void ubifs_remove_from_cat(struct ubifs_info *c,
305 struct ubifs_lprops *lprops, int cat)
306{
307 switch (cat) {
308 case LPROPS_DIRTY:
309 case LPROPS_DIRTY_IDX:
310 case LPROPS_FREE:
311 remove_from_lpt_heap(c, lprops, cat);
312 break;
313 case LPROPS_FREEABLE:
314 c->freeable_cnt -= 1;
315 ubifs_assert(c, c->freeable_cnt >= 0);
316 /* Fall through */
317 case LPROPS_UNCAT:
318 case LPROPS_EMPTY:
319 case LPROPS_FRDI_IDX:
320 ubifs_assert(c, !list_empty(&lprops->list));
321 list_del(&lprops->list);
322 break;
323 default:
324 ubifs_assert(c, 0);
325 }
326
327 c->in_a_category_cnt -= 1;
328 ubifs_assert(c, c->in_a_category_cnt >= 0);
329}
330
331/**
332 * ubifs_replace_cat - replace lprops in a category list or heap.
333 * @c: UBIFS file-system description object
334 * @old_lprops: LEB properties to replace
335 * @new_lprops: LEB properties with which to replace
336 *
337 * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
338 * and the lprops that the pnode contains. When that happens, references in
339 * category lists and heaps must be replaced. This function does that.
340 */
341void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
342 struct ubifs_lprops *new_lprops)
343{
344 int cat;
345
346 cat = new_lprops->flags & LPROPS_CAT_MASK;
347 switch (cat) {
348 case LPROPS_DIRTY:
349 case LPROPS_DIRTY_IDX:
350 case LPROPS_FREE:
351 lpt_heap_replace(c, new_lprops, cat);
352 break;
353 case LPROPS_UNCAT:
354 case LPROPS_EMPTY:
355 case LPROPS_FREEABLE:
356 case LPROPS_FRDI_IDX:
357 list_replace(&old_lprops->list, &new_lprops->list);
358 break;
359 default:
360 ubifs_assert(c, 0);
361 }
362}
363
364/**
365 * ubifs_ensure_cat - ensure LEB properties are categorized.
366 * @c: UBIFS file-system description object
367 * @lprops: LEB properties
368 *
369 * A LEB may have fallen off of the bottom of a heap, and ended up as
370 * un-categorized even though it has enough space for us now. If that is the
371 * case this function will put the LEB back onto a heap.
372 */
373void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops)
374{
375 int cat = lprops->flags & LPROPS_CAT_MASK;
376
377 if (cat != LPROPS_UNCAT)
378 return;
379 cat = ubifs_categorize_lprops(c, lprops);
380 if (cat == LPROPS_UNCAT)
381 return;
382 ubifs_remove_from_cat(c, lprops, LPROPS_UNCAT);
383 ubifs_add_to_cat(c, lprops, cat);
384}
385
386/**
387 * ubifs_categorize_lprops - categorize LEB properties.
388 * @c: UBIFS file-system description object
389 * @lprops: LEB properties to categorize
390 *
391 * LEB properties are categorized to enable fast find operations. This function
392 * returns the LEB category to which the LEB properties belong. Note however
393 * that if the LEB category is stored as a heap and the heap is full, the
394 * LEB properties may have their category changed to %LPROPS_UNCAT.
395 */
396int ubifs_categorize_lprops(const struct ubifs_info *c,
397 const struct ubifs_lprops *lprops)
398{
399 if (lprops->flags & LPROPS_TAKEN)
400 return LPROPS_UNCAT;
401
402 if (lprops->free == c->leb_size) {
403 ubifs_assert(c, !(lprops->flags & LPROPS_INDEX));
404 return LPROPS_EMPTY;
405 }
406
407 if (lprops->free + lprops->dirty == c->leb_size) {
408 if (lprops->flags & LPROPS_INDEX)
409 return LPROPS_FRDI_IDX;
410 else
411 return LPROPS_FREEABLE;
412 }
413
414 if (lprops->flags & LPROPS_INDEX) {
415 if (lprops->dirty + lprops->free >= c->min_idx_node_sz)
416 return LPROPS_DIRTY_IDX;
417 } else {
418 if (lprops->dirty >= c->dead_wm &&
419 lprops->dirty > lprops->free)
420 return LPROPS_DIRTY;
421 if (lprops->free > 0)
422 return LPROPS_FREE;
423 }
424
425 return LPROPS_UNCAT;
426}
427
428/**
429 * change_category - change LEB properties category.
430 * @c: UBIFS file-system description object
431 * @lprops: LEB properties to re-categorize
432 *
433 * LEB properties are categorized to enable fast find operations. When the LEB
434 * properties change they must be re-categorized.
435 */
436static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops)
437{
438 int old_cat = lprops->flags & LPROPS_CAT_MASK;
439 int new_cat = ubifs_categorize_lprops(c, lprops);
440
441 if (old_cat == new_cat) {
442 struct ubifs_lpt_heap *heap;
443
444 /* lprops on a heap now must be moved up or down */
445 if (new_cat < 1 || new_cat > LPROPS_HEAP_CNT)
446 return; /* Not on a heap */
447 heap = &c->lpt_heap[new_cat - 1];
448 adjust_lpt_heap(c, heap, lprops, lprops->hpos, new_cat);
449 } else {
450 ubifs_remove_from_cat(c, lprops, old_cat);
451 ubifs_add_to_cat(c, lprops, new_cat);
452 }
453}
454
455/**
456 * ubifs_calc_dark - calculate LEB dark space size.
457 * @c: the UBIFS file-system description object
458 * @spc: amount of free and dirty space in the LEB
459 *
460 * This function calculates and returns amount of dark space in an LEB which
461 * has @spc bytes of free and dirty space.
462 *
463 * UBIFS is trying to account the space which might not be usable, and this
464 * space is called "dark space". For example, if an LEB has only %512 free
465 * bytes, it is dark space, because it cannot fit a large data node.
466 */
467int ubifs_calc_dark(const struct ubifs_info *c, int spc)
468{
469 ubifs_assert(c, !(spc & 7));
470
471 if (spc < c->dark_wm)
472 return spc;
473
474 /*
475 * If we have slightly more space then the dark space watermark, we can
476 * anyway safely assume it we'll be able to write a node of the
477 * smallest size there.
478 */
479 if (spc - c->dark_wm < MIN_WRITE_SZ)
480 return spc - MIN_WRITE_SZ;
481
482 return c->dark_wm;
483}
484
485/**
486 * is_lprops_dirty - determine if LEB properties are dirty.
487 * @c: the UBIFS file-system description object
488 * @lprops: LEB properties to test
489 */
490static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops)
491{
492 struct ubifs_pnode *pnode;
493 int pos;
494
495 pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1);
496 pnode = (struct ubifs_pnode *)container_of(lprops - pos,
497 struct ubifs_pnode,
498 lprops[0]);
499 return !test_bit(COW_CNODE, &pnode->flags) &&
500 test_bit(DIRTY_CNODE, &pnode->flags);
501}
502
503/**
504 * ubifs_change_lp - change LEB properties.
505 * @c: the UBIFS file-system description object
506 * @lp: LEB properties to change
507 * @free: new free space amount
508 * @dirty: new dirty space amount
509 * @flags: new flags
510 * @idx_gc_cnt: change to the count of @idx_gc list
511 *
512 * This function changes LEB properties (@free, @dirty or @flag). However, the
513 * property which has the %LPROPS_NC value is not changed. Returns a pointer to
514 * the updated LEB properties on success and a negative error code on failure.
515 *
516 * Note, the LEB properties may have had to be copied (due to COW) and
517 * consequently the pointer returned may not be the same as the pointer
518 * passed.
519 */
520const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
521 const struct ubifs_lprops *lp,
522 int free, int dirty, int flags,
523 int idx_gc_cnt)
524{
525 /*
526 * This is the only function that is allowed to change lprops, so we
527 * discard the "const" qualifier.
528 */
529 struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp;
530
531 dbg_lp("LEB %d, free %d, dirty %d, flags %d",
532 lprops->lnum, free, dirty, flags);
533
534 ubifs_assert(c, mutex_is_locked(&c->lp_mutex));
535 ubifs_assert(c, c->lst.empty_lebs >= 0 &&
536 c->lst.empty_lebs <= c->main_lebs);
537 ubifs_assert(c, c->freeable_cnt >= 0);
538 ubifs_assert(c, c->freeable_cnt <= c->main_lebs);
539 ubifs_assert(c, c->lst.taken_empty_lebs >= 0);
540 ubifs_assert(c, c->lst.taken_empty_lebs <= c->lst.empty_lebs);
541 ubifs_assert(c, !(c->lst.total_free & 7) && !(c->lst.total_dirty & 7));
542 ubifs_assert(c, !(c->lst.total_dead & 7) && !(c->lst.total_dark & 7));
543 ubifs_assert(c, !(c->lst.total_used & 7));
544 ubifs_assert(c, free == LPROPS_NC || free >= 0);
545 ubifs_assert(c, dirty == LPROPS_NC || dirty >= 0);
546
547 if (!is_lprops_dirty(c, lprops)) {
548 lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum);
549 if (IS_ERR(lprops))
550 return lprops;
551 } else
552 ubifs_assert(c, lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum));
553
554 ubifs_assert(c, !(lprops->free & 7) && !(lprops->dirty & 7));
555
556 spin_lock(&c->space_lock);
557 if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
558 c->lst.taken_empty_lebs -= 1;
559
560 if (!(lprops->flags & LPROPS_INDEX)) {
561 int old_spc;
562
563 old_spc = lprops->free + lprops->dirty;
564 if (old_spc < c->dead_wm)
565 c->lst.total_dead -= old_spc;
566 else
567 c->lst.total_dark -= ubifs_calc_dark(c, old_spc);
568
569 c->lst.total_used -= c->leb_size - old_spc;
570 }
571
572 if (free != LPROPS_NC) {
573 free = ALIGN(free, 8);
574 c->lst.total_free += free - lprops->free;
575
576 /* Increase or decrease empty LEBs counter if needed */
577 if (free == c->leb_size) {
578 if (lprops->free != c->leb_size)
579 c->lst.empty_lebs += 1;
580 } else if (lprops->free == c->leb_size)
581 c->lst.empty_lebs -= 1;
582 lprops->free = free;
583 }
584
585 if (dirty != LPROPS_NC) {
586 dirty = ALIGN(dirty, 8);
587 c->lst.total_dirty += dirty - lprops->dirty;
588 lprops->dirty = dirty;
589 }
590
591 if (flags != LPROPS_NC) {
592 /* Take care about indexing LEBs counter if needed */
593 if ((lprops->flags & LPROPS_INDEX)) {
594 if (!(flags & LPROPS_INDEX))
595 c->lst.idx_lebs -= 1;
596 } else if (flags & LPROPS_INDEX)
597 c->lst.idx_lebs += 1;
598 lprops->flags = flags;
599 }
600
601 if (!(lprops->flags & LPROPS_INDEX)) {
602 int new_spc;
603
604 new_spc = lprops->free + lprops->dirty;
605 if (new_spc < c->dead_wm)
606 c->lst.total_dead += new_spc;
607 else
608 c->lst.total_dark += ubifs_calc_dark(c, new_spc);
609
610 c->lst.total_used += c->leb_size - new_spc;
611 }
612
613 if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
614 c->lst.taken_empty_lebs += 1;
615
616 change_category(c, lprops);
617 c->idx_gc_cnt += idx_gc_cnt;
618 spin_unlock(&c->space_lock);
619 return lprops;
620}
621
622/**
623 * ubifs_get_lp_stats - get lprops statistics.
624 * @c: UBIFS file-system description object
625 * @lst: return statistics
626 */
627void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst)
628{
629 spin_lock(&c->space_lock);
630 memcpy(lst, &c->lst, sizeof(struct ubifs_lp_stats));
631 spin_unlock(&c->space_lock);
632}
633
634/**
635 * ubifs_change_one_lp - change LEB properties.
636 * @c: the UBIFS file-system description object
637 * @lnum: LEB to change properties for
638 * @free: amount of free space
639 * @dirty: amount of dirty space
640 * @flags_set: flags to set
641 * @flags_clean: flags to clean
642 * @idx_gc_cnt: change to the count of idx_gc list
643 *
644 * This function changes properties of LEB @lnum. It is a helper wrapper over
645 * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the
646 * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and
647 * a negative error code in case of failure.
648 */
649int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
650 int flags_set, int flags_clean, int idx_gc_cnt)
651{
652 int err = 0, flags;
653 const struct ubifs_lprops *lp;
654
655 ubifs_get_lprops(c);
656
657 lp = ubifs_lpt_lookup_dirty(c, lnum);
658 if (IS_ERR(lp)) {
659 err = PTR_ERR(lp);
660 goto out;
661 }
662
663 flags = (lp->flags | flags_set) & ~flags_clean;
664 lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt);
665 if (IS_ERR(lp))
666 err = PTR_ERR(lp);
667
668out:
669 ubifs_release_lprops(c);
670 if (err)
671 ubifs_err(c, "cannot change properties of LEB %d, error %d",
672 lnum, err);
673 return err;
674}
675
676/**
677 * ubifs_update_one_lp - update LEB properties.
678 * @c: the UBIFS file-system description object
679 * @lnum: LEB to change properties for
680 * @free: amount of free space
681 * @dirty: amount of dirty space to add
682 * @flags_set: flags to set
683 * @flags_clean: flags to clean
684 *
685 * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to
686 * current dirty space, not substitutes it.
687 */
688int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
689 int flags_set, int flags_clean)
690{
691 int err = 0, flags;
692 const struct ubifs_lprops *lp;
693
694 ubifs_get_lprops(c);
695
696 lp = ubifs_lpt_lookup_dirty(c, lnum);
697 if (IS_ERR(lp)) {
698 err = PTR_ERR(lp);
699 goto out;
700 }
701
702 flags = (lp->flags | flags_set) & ~flags_clean;
703 lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0);
704 if (IS_ERR(lp))
705 err = PTR_ERR(lp);
706
707out:
708 ubifs_release_lprops(c);
709 if (err)
710 ubifs_err(c, "cannot update properties of LEB %d, error %d",
711 lnum, err);
712 return err;
713}
714
715/**
716 * ubifs_read_one_lp - read LEB properties.
717 * @c: the UBIFS file-system description object
718 * @lnum: LEB to read properties for
719 * @lp: where to store read properties
720 *
721 * This helper function reads properties of a LEB @lnum and stores them in @lp.
722 * Returns zero in case of success and a negative error code in case of
723 * failure.
724 */
725int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp)
726{
727 int err = 0;
728 const struct ubifs_lprops *lpp;
729
730 ubifs_get_lprops(c);
731
732 lpp = ubifs_lpt_lookup(c, lnum);
733 if (IS_ERR(lpp)) {
734 err = PTR_ERR(lpp);
735 ubifs_err(c, "cannot read properties of LEB %d, error %d",
736 lnum, err);
737 goto out;
738 }
739
740 memcpy(lp, lpp, sizeof(struct ubifs_lprops));
741
742out:
743 ubifs_release_lprops(c);
744 return err;
745}
746
747/**
748 * ubifs_fast_find_free - try to find a LEB with free space quickly.
749 * @c: the UBIFS file-system description object
750 *
751 * This function returns LEB properties for a LEB with free space or %NULL if
752 * the function is unable to find a LEB quickly.
753 */
754const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c)
755{
756 struct ubifs_lprops *lprops;
757 struct ubifs_lpt_heap *heap;
758
759 ubifs_assert(c, mutex_is_locked(&c->lp_mutex));
760
761 heap = &c->lpt_heap[LPROPS_FREE - 1];
762 if (heap->cnt == 0)
763 return NULL;
764
765 lprops = heap->arr[0];
766 ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN));
767 ubifs_assert(c, !(lprops->flags & LPROPS_INDEX));
768 return lprops;
769}
770
771/**
772 * ubifs_fast_find_empty - try to find an empty LEB quickly.
773 * @c: the UBIFS file-system description object
774 *
775 * This function returns LEB properties for an empty LEB or %NULL if the
776 * function is unable to find an empty LEB quickly.
777 */
778const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c)
779{
780 struct ubifs_lprops *lprops;
781
782 ubifs_assert(c, mutex_is_locked(&c->lp_mutex));
783
784 if (list_empty(&c->empty_list))
785 return NULL;
786
787 lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list);
788 ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN));
789 ubifs_assert(c, !(lprops->flags & LPROPS_INDEX));
790 ubifs_assert(c, lprops->free == c->leb_size);
791 return lprops;
792}
793
794/**
795 * ubifs_fast_find_freeable - try to find a freeable LEB quickly.
796 * @c: the UBIFS file-system description object
797 *
798 * This function returns LEB properties for a freeable LEB or %NULL if the
799 * function is unable to find a freeable LEB quickly.
800 */
801const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c)
802{
803 struct ubifs_lprops *lprops;
804
805 ubifs_assert(c, mutex_is_locked(&c->lp_mutex));
806
807 if (list_empty(&c->freeable_list))
808 return NULL;
809
810 lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list);
811 ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN));
812 ubifs_assert(c, !(lprops->flags & LPROPS_INDEX));
813 ubifs_assert(c, lprops->free + lprops->dirty == c->leb_size);
814 ubifs_assert(c, c->freeable_cnt > 0);
815 return lprops;
816}
817
818/**
819 * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly.
820 * @c: the UBIFS file-system description object
821 *
822 * This function returns LEB properties for a freeable index LEB or %NULL if the
823 * function is unable to find a freeable index LEB quickly.
824 */
825const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c)
826{
827 struct ubifs_lprops *lprops;
828
829 ubifs_assert(c, mutex_is_locked(&c->lp_mutex));
830
831 if (list_empty(&c->frdi_idx_list))
832 return NULL;
833
834 lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list);
835 ubifs_assert(c, !(lprops->flags & LPROPS_TAKEN));
836 ubifs_assert(c, (lprops->flags & LPROPS_INDEX));
837 ubifs_assert(c, lprops->free + lprops->dirty == c->leb_size);
838 return lprops;
839}
840
841/*
842 * Everything below is related to debugging.
843 */
844
845/**
846 * dbg_check_cats - check category heaps and lists.
847 * @c: UBIFS file-system description object
848 *
849 * This function returns %0 on success and a negative error code on failure.
850 */
851int dbg_check_cats(struct ubifs_info *c)
852{
853 struct ubifs_lprops *lprops;
854 struct list_head *pos;
855 int i, cat;
856
857 if (!dbg_is_chk_gen(c) && !dbg_is_chk_lprops(c))
858 return 0;
859
860 list_for_each_entry(lprops, &c->empty_list, list) {
861 if (lprops->free != c->leb_size) {
862 ubifs_err(c, "non-empty LEB %d on empty list (free %d dirty %d flags %d)",
863 lprops->lnum, lprops->free, lprops->dirty,
864 lprops->flags);
865 return -EINVAL;
866 }
867 if (lprops->flags & LPROPS_TAKEN) {
868 ubifs_err(c, "taken LEB %d on empty list (free %d dirty %d flags %d)",
869 lprops->lnum, lprops->free, lprops->dirty,
870 lprops->flags);
871 return -EINVAL;
872 }
873 }
874
875 i = 0;
876 list_for_each_entry(lprops, &c->freeable_list, list) {
877 if (lprops->free + lprops->dirty != c->leb_size) {
878 ubifs_err(c, "non-freeable LEB %d on freeable list (free %d dirty %d flags %d)",
879 lprops->lnum, lprops->free, lprops->dirty,
880 lprops->flags);
881 return -EINVAL;
882 }
883 if (lprops->flags & LPROPS_TAKEN) {
884 ubifs_err(c, "taken LEB %d on freeable list (free %d dirty %d flags %d)",
885 lprops->lnum, lprops->free, lprops->dirty,
886 lprops->flags);
887 return -EINVAL;
888 }
889 i += 1;
890 }
891 if (i != c->freeable_cnt) {
892 ubifs_err(c, "freeable list count %d expected %d", i,
893 c->freeable_cnt);
894 return -EINVAL;
895 }
896
897 i = 0;
898 list_for_each(pos, &c->idx_gc)
899 i += 1;
900 if (i != c->idx_gc_cnt) {
901 ubifs_err(c, "idx_gc list count %d expected %d", i,
902 c->idx_gc_cnt);
903 return -EINVAL;
904 }
905
906 list_for_each_entry(lprops, &c->frdi_idx_list, list) {
907 if (lprops->free + lprops->dirty != c->leb_size) {
908 ubifs_err(c, "non-freeable LEB %d on frdi_idx list (free %d dirty %d flags %d)",
909 lprops->lnum, lprops->free, lprops->dirty,
910 lprops->flags);
911 return -EINVAL;
912 }
913 if (lprops->flags & LPROPS_TAKEN) {
914 ubifs_err(c, "taken LEB %d on frdi_idx list (free %d dirty %d flags %d)",
915 lprops->lnum, lprops->free, lprops->dirty,
916 lprops->flags);
917 return -EINVAL;
918 }
919 if (!(lprops->flags & LPROPS_INDEX)) {
920 ubifs_err(c, "non-index LEB %d on frdi_idx list (free %d dirty %d flags %d)",
921 lprops->lnum, lprops->free, lprops->dirty,
922 lprops->flags);
923 return -EINVAL;
924 }
925 }
926
927 for (cat = 1; cat <= LPROPS_HEAP_CNT; cat++) {
928 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
929
930 for (i = 0; i < heap->cnt; i++) {
931 lprops = heap->arr[i];
932 if (!lprops) {
933 ubifs_err(c, "null ptr in LPT heap cat %d", cat);
934 return -EINVAL;
935 }
936 if (lprops->hpos != i) {
937 ubifs_err(c, "bad ptr in LPT heap cat %d", cat);
938 return -EINVAL;
939 }
940 if (lprops->flags & LPROPS_TAKEN) {
941 ubifs_err(c, "taken LEB in LPT heap cat %d", cat);
942 return -EINVAL;
943 }
944 }
945 }
946
947 return 0;
948}
949
950void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
951 int add_pos)
952{
953 int i = 0, j, err = 0;
954
955 if (!dbg_is_chk_gen(c) && !dbg_is_chk_lprops(c))
956 return;
957
958 for (i = 0; i < heap->cnt; i++) {
959 struct ubifs_lprops *lprops = heap->arr[i];
960 struct ubifs_lprops *lp;
961
962 if (i != add_pos)
963 if ((lprops->flags & LPROPS_CAT_MASK) != cat) {
964 err = 1;
965 goto out;
966 }
967 if (lprops->hpos != i) {
968 err = 2;
969 goto out;
970 }
971 lp = ubifs_lpt_lookup(c, lprops->lnum);
972 if (IS_ERR(lp)) {
973 err = 3;
974 goto out;
975 }
976 if (lprops != lp) {
977 ubifs_err(c, "lprops %zx lp %zx lprops->lnum %d lp->lnum %d",
978 (size_t)lprops, (size_t)lp, lprops->lnum,
979 lp->lnum);
980 err = 4;
981 goto out;
982 }
983 for (j = 0; j < i; j++) {
984 lp = heap->arr[j];
985 if (lp == lprops) {
986 err = 5;
987 goto out;
988 }
989 if (lp->lnum == lprops->lnum) {
990 err = 6;
991 goto out;
992 }
993 }
994 }
995out:
996 if (err) {
997 ubifs_err(c, "failed cat %d hpos %d err %d", cat, i, err);
998 dump_stack();
999 ubifs_dump_heap(c, heap, cat);
1000 }
1001}
1002
1003/**
1004 * scan_check_cb - scan callback.
1005 * @c: the UBIFS file-system description object
1006 * @lp: LEB properties to scan
1007 * @in_tree: whether the LEB properties are in main memory
1008 * @lst: lprops statistics to update
1009 *
1010 * This function returns a code that indicates whether the scan should continue
1011 * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
1012 * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
1013 * (%LPT_SCAN_STOP).
1014 */
1015static int scan_check_cb(struct ubifs_info *c,
1016 const struct ubifs_lprops *lp, int in_tree,
1017 struct ubifs_lp_stats *lst)
1018{
1019 struct ubifs_scan_leb *sleb;
1020 struct ubifs_scan_node *snod;
1021 int cat, lnum = lp->lnum, is_idx = 0, used = 0, free, dirty, ret;
1022 void *buf = NULL;
1023
1024 cat = lp->flags & LPROPS_CAT_MASK;
1025 if (cat != LPROPS_UNCAT) {
1026 cat = ubifs_categorize_lprops(c, lp);
1027 if (cat != (lp->flags & LPROPS_CAT_MASK)) {
1028 ubifs_err(c, "bad LEB category %d expected %d",
1029 (lp->flags & LPROPS_CAT_MASK), cat);
1030 return -EINVAL;
1031 }
1032 }
1033
1034 /* Check lp is on its category list (if it has one) */
1035 if (in_tree) {
1036 struct list_head *list = NULL;
1037
1038 switch (cat) {
1039 case LPROPS_EMPTY:
1040 list = &c->empty_list;
1041 break;
1042 case LPROPS_FREEABLE:
1043 list = &c->freeable_list;
1044 break;
1045 case LPROPS_FRDI_IDX:
1046 list = &c->frdi_idx_list;
1047 break;
1048 case LPROPS_UNCAT:
1049 list = &c->uncat_list;
1050 break;
1051 }
1052 if (list) {
1053 struct ubifs_lprops *lprops;
1054 int found = 0;
1055
1056 list_for_each_entry(lprops, list, list) {
1057 if (lprops == lp) {
1058 found = 1;
1059 break;
1060 }
1061 }
1062 if (!found) {
1063 ubifs_err(c, "bad LPT list (category %d)", cat);
1064 return -EINVAL;
1065 }
1066 }
1067 }
1068
1069 /* Check lp is on its category heap (if it has one) */
1070 if (in_tree && cat > 0 && cat <= LPROPS_HEAP_CNT) {
1071 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
1072
1073 if ((lp->hpos != -1 && heap->arr[lp->hpos]->lnum != lnum) ||
1074 lp != heap->arr[lp->hpos]) {
1075 ubifs_err(c, "bad LPT heap (category %d)", cat);
1076 return -EINVAL;
1077 }
1078 }
1079
1080 /*
1081 * After an unclean unmount, empty and freeable LEBs
1082 * may contain garbage - do not scan them.
1083 */
1084 if (lp->free == c->leb_size) {
1085 lst->empty_lebs += 1;
1086 lst->total_free += c->leb_size;
1087 lst->total_dark += ubifs_calc_dark(c, c->leb_size);
1088 return LPT_SCAN_CONTINUE;
1089 }
1090 if (lp->free + lp->dirty == c->leb_size &&
1091 !(lp->flags & LPROPS_INDEX)) {
1092 lst->total_free += lp->free;
1093 lst->total_dirty += lp->dirty;
1094 lst->total_dark += ubifs_calc_dark(c, c->leb_size);
1095 return LPT_SCAN_CONTINUE;
1096 }
1097
1098 buf = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
1099 if (!buf)
1100 return -ENOMEM;
1101
1102 sleb = ubifs_scan(c, lnum, 0, buf, 0);
1103 if (IS_ERR(sleb)) {
1104 ret = PTR_ERR(sleb);
1105 if (ret == -EUCLEAN) {
1106 ubifs_dump_lprops(c);
1107 ubifs_dump_budg(c, &c->bi);
1108 }
1109 goto out;
1110 }
1111
1112 is_idx = -1;
1113 list_for_each_entry(snod, &sleb->nodes, list) {
1114 int found, level = 0;
1115
1116 cond_resched();
1117
1118 if (is_idx == -1)
1119 is_idx = (snod->type == UBIFS_IDX_NODE) ? 1 : 0;
1120
1121 if (is_idx && snod->type != UBIFS_IDX_NODE) {
1122 ubifs_err(c, "indexing node in data LEB %d:%d",
1123 lnum, snod->offs);
1124 goto out_destroy;
1125 }
1126
1127 if (snod->type == UBIFS_IDX_NODE) {
1128 struct ubifs_idx_node *idx = snod->node;
1129
1130 key_read(c, ubifs_idx_key(c, idx), &snod->key);
1131 level = le16_to_cpu(idx->level);
1132 }
1133
1134 found = ubifs_tnc_has_node(c, &snod->key, level, lnum,
1135 snod->offs, is_idx);
1136 if (found) {
1137 if (found < 0)
1138 goto out_destroy;
1139 used += ALIGN(snod->len, 8);
1140 }
1141 }
1142
1143 free = c->leb_size - sleb->endpt;
1144 dirty = sleb->endpt - used;
1145
1146 if (free > c->leb_size || free < 0 || dirty > c->leb_size ||
1147 dirty < 0) {
1148 ubifs_err(c, "bad calculated accounting for LEB %d: free %d, dirty %d",
1149 lnum, free, dirty);
1150 goto out_destroy;
1151 }
1152
1153 if (lp->free + lp->dirty == c->leb_size &&
1154 free + dirty == c->leb_size)
1155 if ((is_idx && !(lp->flags & LPROPS_INDEX)) ||
1156 (!is_idx && free == c->leb_size) ||
1157 lp->free == c->leb_size) {
1158 /*
1159 * Empty or freeable LEBs could contain index
1160 * nodes from an uncompleted commit due to an
1161 * unclean unmount. Or they could be empty for
1162 * the same reason. Or it may simply not have been
1163 * unmapped.
1164 */
1165 free = lp->free;
1166 dirty = lp->dirty;
1167 is_idx = 0;
1168 }
1169
1170 if (is_idx && lp->free + lp->dirty == free + dirty &&
1171 lnum != c->ihead_lnum) {
1172 /*
1173 * After an unclean unmount, an index LEB could have a different
1174 * amount of free space than the value recorded by lprops. That
1175 * is because the in-the-gaps method may use free space or
1176 * create free space (as a side-effect of using ubi_leb_change
1177 * and not writing the whole LEB). The incorrect free space
1178 * value is not a problem because the index is only ever
1179 * allocated empty LEBs, so there will never be an attempt to
1180 * write to the free space at the end of an index LEB - except
1181 * by the in-the-gaps method for which it is not a problem.
1182 */
1183 free = lp->free;
1184 dirty = lp->dirty;
1185 }
1186
1187 if (lp->free != free || lp->dirty != dirty)
1188 goto out_print;
1189
1190 if (is_idx && !(lp->flags & LPROPS_INDEX)) {
1191 if (free == c->leb_size)
1192 /* Free but not unmapped LEB, it's fine */
1193 is_idx = 0;
1194 else {
1195 ubifs_err(c, "indexing node without indexing flag");
1196 goto out_print;
1197 }
1198 }
1199
1200 if (!is_idx && (lp->flags & LPROPS_INDEX)) {
1201 ubifs_err(c, "data node with indexing flag");
1202 goto out_print;
1203 }
1204
1205 if (free == c->leb_size)
1206 lst->empty_lebs += 1;
1207
1208 if (is_idx)
1209 lst->idx_lebs += 1;
1210
1211 if (!(lp->flags & LPROPS_INDEX))
1212 lst->total_used += c->leb_size - free - dirty;
1213 lst->total_free += free;
1214 lst->total_dirty += dirty;
1215
1216 if (!(lp->flags & LPROPS_INDEX)) {
1217 int spc = free + dirty;
1218
1219 if (spc < c->dead_wm)
1220 lst->total_dead += spc;
1221 else
1222 lst->total_dark += ubifs_calc_dark(c, spc);
1223 }
1224
1225 ubifs_scan_destroy(sleb);
1226 vfree(buf);
1227 return LPT_SCAN_CONTINUE;
1228
1229out_print:
1230 ubifs_err(c, "bad accounting of LEB %d: free %d, dirty %d flags %#x, should be free %d, dirty %d",
1231 lnum, lp->free, lp->dirty, lp->flags, free, dirty);
1232 ubifs_dump_leb(c, lnum);
1233out_destroy:
1234 ubifs_scan_destroy(sleb);
1235 ret = -EINVAL;
1236out:
1237 vfree(buf);
1238 return ret;
1239}
1240
1241/**
1242 * dbg_check_lprops - check all LEB properties.
1243 * @c: UBIFS file-system description object
1244 *
1245 * This function checks all LEB properties and makes sure they are all correct.
1246 * It returns zero if everything is fine, %-EINVAL if there is an inconsistency
1247 * and other negative error codes in case of other errors. This function is
1248 * called while the file system is locked (because of commit start), so no
1249 * additional locking is required. Note that locking the LPT mutex would cause
1250 * a circular lock dependency with the TNC mutex.
1251 */
1252int dbg_check_lprops(struct ubifs_info *c)
1253{
1254 int i, err;
1255 struct ubifs_lp_stats lst;
1256
1257 if (!dbg_is_chk_lprops(c))
1258 return 0;
1259
1260 /*
1261 * As we are going to scan the media, the write buffers have to be
1262 * synchronized.
1263 */
1264 for (i = 0; i < c->jhead_cnt; i++) {
1265 err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
1266 if (err)
1267 return err;
1268 }
1269
1270 memset(&lst, 0, sizeof(struct ubifs_lp_stats));
1271 err = ubifs_lpt_scan_nolock(c, c->main_first, c->leb_cnt - 1,
1272 (ubifs_lpt_scan_callback)scan_check_cb,
1273 &lst);
1274 if (err && err != -ENOSPC)
1275 goto out;
1276
1277 if (lst.empty_lebs != c->lst.empty_lebs ||
1278 lst.idx_lebs != c->lst.idx_lebs ||
1279 lst.total_free != c->lst.total_free ||
1280 lst.total_dirty != c->lst.total_dirty ||
1281 lst.total_used != c->lst.total_used) {
1282 ubifs_err(c, "bad overall accounting");
1283 ubifs_err(c, "calculated: empty_lebs %d, idx_lebs %d, total_free %lld, total_dirty %lld, total_used %lld",
1284 lst.empty_lebs, lst.idx_lebs, lst.total_free,
1285 lst.total_dirty, lst.total_used);
1286 ubifs_err(c, "read from lprops: empty_lebs %d, idx_lebs %d, total_free %lld, total_dirty %lld, total_used %lld",
1287 c->lst.empty_lebs, c->lst.idx_lebs, c->lst.total_free,
1288 c->lst.total_dirty, c->lst.total_used);
1289 err = -EINVAL;
1290 goto out;
1291 }
1292
1293 if (lst.total_dead != c->lst.total_dead ||
1294 lst.total_dark != c->lst.total_dark) {
1295 ubifs_err(c, "bad dead/dark space accounting");
1296 ubifs_err(c, "calculated: total_dead %lld, total_dark %lld",
1297 lst.total_dead, lst.total_dark);
1298 ubifs_err(c, "read from lprops: total_dead %lld, total_dark %lld",
1299 c->lst.total_dead, c->lst.total_dark);
1300 err = -EINVAL;
1301 goto out;
1302 }
1303
1304 err = dbg_check_cats(c);
1305out:
1306 return err;
1307}
1/*
2 * This file is part of UBIFS.
3 *
4 * Copyright (C) 2006-2008 Nokia Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * more details.
14 *
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 51
17 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Authors: Adrian Hunter
20 * Artem Bityutskiy (Битюцкий Артём)
21 */
22
23/*
24 * This file implements the functions that access LEB properties and their
25 * categories. LEBs are categorized based on the needs of UBIFS, and the
26 * categories are stored as either heaps or lists to provide a fast way of
27 * finding a LEB in a particular category. For example, UBIFS may need to find
28 * an empty LEB for the journal, or a very dirty LEB for garbage collection.
29 */
30
31#include "ubifs.h"
32
33/**
34 * get_heap_comp_val - get the LEB properties value for heap comparisons.
35 * @lprops: LEB properties
36 * @cat: LEB category
37 */
38static int get_heap_comp_val(struct ubifs_lprops *lprops, int cat)
39{
40 switch (cat) {
41 case LPROPS_FREE:
42 return lprops->free;
43 case LPROPS_DIRTY_IDX:
44 return lprops->free + lprops->dirty;
45 default:
46 return lprops->dirty;
47 }
48}
49
50/**
51 * move_up_lpt_heap - move a new heap entry up as far as possible.
52 * @c: UBIFS file-system description object
53 * @heap: LEB category heap
54 * @lprops: LEB properties to move
55 * @cat: LEB category
56 *
57 * New entries to a heap are added at the bottom and then moved up until the
58 * parent's value is greater. In the case of LPT's category heaps, the value
59 * is either the amount of free space or the amount of dirty space, depending
60 * on the category.
61 */
62static void move_up_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
63 struct ubifs_lprops *lprops, int cat)
64{
65 int val1, val2, hpos;
66
67 hpos = lprops->hpos;
68 if (!hpos)
69 return; /* Already top of the heap */
70 val1 = get_heap_comp_val(lprops, cat);
71 /* Compare to parent and, if greater, move up the heap */
72 do {
73 int ppos = (hpos - 1) / 2;
74
75 val2 = get_heap_comp_val(heap->arr[ppos], cat);
76 if (val2 >= val1)
77 return;
78 /* Greater than parent so move up */
79 heap->arr[ppos]->hpos = hpos;
80 heap->arr[hpos] = heap->arr[ppos];
81 heap->arr[ppos] = lprops;
82 lprops->hpos = ppos;
83 hpos = ppos;
84 } while (hpos);
85}
86
87/**
88 * adjust_lpt_heap - move a changed heap entry up or down the heap.
89 * @c: UBIFS file-system description object
90 * @heap: LEB category heap
91 * @lprops: LEB properties to move
92 * @hpos: heap position of @lprops
93 * @cat: LEB category
94 *
95 * Changed entries in a heap are moved up or down until the parent's value is
96 * greater. In the case of LPT's category heaps, the value is either the amount
97 * of free space or the amount of dirty space, depending on the category.
98 */
99static void adjust_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
100 struct ubifs_lprops *lprops, int hpos, int cat)
101{
102 int val1, val2, val3, cpos;
103
104 val1 = get_heap_comp_val(lprops, cat);
105 /* Compare to parent and, if greater than parent, move up the heap */
106 if (hpos) {
107 int ppos = (hpos - 1) / 2;
108
109 val2 = get_heap_comp_val(heap->arr[ppos], cat);
110 if (val1 > val2) {
111 /* Greater than parent so move up */
112 while (1) {
113 heap->arr[ppos]->hpos = hpos;
114 heap->arr[hpos] = heap->arr[ppos];
115 heap->arr[ppos] = lprops;
116 lprops->hpos = ppos;
117 hpos = ppos;
118 if (!hpos)
119 return;
120 ppos = (hpos - 1) / 2;
121 val2 = get_heap_comp_val(heap->arr[ppos], cat);
122 if (val1 <= val2)
123 return;
124 /* Still greater than parent so keep going */
125 }
126 }
127 }
128
129 /* Not greater than parent, so compare to children */
130 while (1) {
131 /* Compare to left child */
132 cpos = hpos * 2 + 1;
133 if (cpos >= heap->cnt)
134 return;
135 val2 = get_heap_comp_val(heap->arr[cpos], cat);
136 if (val1 < val2) {
137 /* Less than left child, so promote biggest child */
138 if (cpos + 1 < heap->cnt) {
139 val3 = get_heap_comp_val(heap->arr[cpos + 1],
140 cat);
141 if (val3 > val2)
142 cpos += 1; /* Right child is bigger */
143 }
144 heap->arr[cpos]->hpos = hpos;
145 heap->arr[hpos] = heap->arr[cpos];
146 heap->arr[cpos] = lprops;
147 lprops->hpos = cpos;
148 hpos = cpos;
149 continue;
150 }
151 /* Compare to right child */
152 cpos += 1;
153 if (cpos >= heap->cnt)
154 return;
155 val3 = get_heap_comp_val(heap->arr[cpos], cat);
156 if (val1 < val3) {
157 /* Less than right child, so promote right child */
158 heap->arr[cpos]->hpos = hpos;
159 heap->arr[hpos] = heap->arr[cpos];
160 heap->arr[cpos] = lprops;
161 lprops->hpos = cpos;
162 hpos = cpos;
163 continue;
164 }
165 return;
166 }
167}
168
169/**
170 * add_to_lpt_heap - add LEB properties to a LEB category heap.
171 * @c: UBIFS file-system description object
172 * @lprops: LEB properties to add
173 * @cat: LEB category
174 *
175 * This function returns %1 if @lprops is added to the heap for LEB category
176 * @cat, otherwise %0 is returned because the heap is full.
177 */
178static int add_to_lpt_heap(struct ubifs_info *c, struct ubifs_lprops *lprops,
179 int cat)
180{
181 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
182
183 if (heap->cnt >= heap->max_cnt) {
184 const int b = LPT_HEAP_SZ / 2 - 1;
185 int cpos, val1, val2;
186
187 /* Compare to some other LEB on the bottom of heap */
188 /* Pick a position kind of randomly */
189 cpos = (((size_t)lprops >> 4) & b) + b;
190 ubifs_assert(cpos >= b);
191 ubifs_assert(cpos < LPT_HEAP_SZ);
192 ubifs_assert(cpos < heap->cnt);
193
194 val1 = get_heap_comp_val(lprops, cat);
195 val2 = get_heap_comp_val(heap->arr[cpos], cat);
196 if (val1 > val2) {
197 struct ubifs_lprops *lp;
198
199 lp = heap->arr[cpos];
200 lp->flags &= ~LPROPS_CAT_MASK;
201 lp->flags |= LPROPS_UNCAT;
202 list_add(&lp->list, &c->uncat_list);
203 lprops->hpos = cpos;
204 heap->arr[cpos] = lprops;
205 move_up_lpt_heap(c, heap, lprops, cat);
206 dbg_check_heap(c, heap, cat, lprops->hpos);
207 return 1; /* Added to heap */
208 }
209 dbg_check_heap(c, heap, cat, -1);
210 return 0; /* Not added to heap */
211 } else {
212 lprops->hpos = heap->cnt++;
213 heap->arr[lprops->hpos] = lprops;
214 move_up_lpt_heap(c, heap, lprops, cat);
215 dbg_check_heap(c, heap, cat, lprops->hpos);
216 return 1; /* Added to heap */
217 }
218}
219
220/**
221 * remove_from_lpt_heap - remove LEB properties from a LEB category heap.
222 * @c: UBIFS file-system description object
223 * @lprops: LEB properties to remove
224 * @cat: LEB category
225 */
226static void remove_from_lpt_heap(struct ubifs_info *c,
227 struct ubifs_lprops *lprops, int cat)
228{
229 struct ubifs_lpt_heap *heap;
230 int hpos = lprops->hpos;
231
232 heap = &c->lpt_heap[cat - 1];
233 ubifs_assert(hpos >= 0 && hpos < heap->cnt);
234 ubifs_assert(heap->arr[hpos] == lprops);
235 heap->cnt -= 1;
236 if (hpos < heap->cnt) {
237 heap->arr[hpos] = heap->arr[heap->cnt];
238 heap->arr[hpos]->hpos = hpos;
239 adjust_lpt_heap(c, heap, heap->arr[hpos], hpos, cat);
240 }
241 dbg_check_heap(c, heap, cat, -1);
242}
243
244/**
245 * lpt_heap_replace - replace lprops in a category heap.
246 * @c: UBIFS file-system description object
247 * @old_lprops: LEB properties to replace
248 * @new_lprops: LEB properties with which to replace
249 * @cat: LEB category
250 *
251 * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
252 * and the lprops that the pnode contains. When that happens, references in
253 * the category heaps to those lprops must be updated to point to the new
254 * lprops. This function does that.
255 */
256static void lpt_heap_replace(struct ubifs_info *c,
257 struct ubifs_lprops *old_lprops,
258 struct ubifs_lprops *new_lprops, int cat)
259{
260 struct ubifs_lpt_heap *heap;
261 int hpos = new_lprops->hpos;
262
263 heap = &c->lpt_heap[cat - 1];
264 heap->arr[hpos] = new_lprops;
265}
266
267/**
268 * ubifs_add_to_cat - add LEB properties to a category list or heap.
269 * @c: UBIFS file-system description object
270 * @lprops: LEB properties to add
271 * @cat: LEB category to which to add
272 *
273 * LEB properties are categorized to enable fast find operations.
274 */
275void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
276 int cat)
277{
278 switch (cat) {
279 case LPROPS_DIRTY:
280 case LPROPS_DIRTY_IDX:
281 case LPROPS_FREE:
282 if (add_to_lpt_heap(c, lprops, cat))
283 break;
284 /* No more room on heap so make it un-categorized */
285 cat = LPROPS_UNCAT;
286 /* Fall through */
287 case LPROPS_UNCAT:
288 list_add(&lprops->list, &c->uncat_list);
289 break;
290 case LPROPS_EMPTY:
291 list_add(&lprops->list, &c->empty_list);
292 break;
293 case LPROPS_FREEABLE:
294 list_add(&lprops->list, &c->freeable_list);
295 c->freeable_cnt += 1;
296 break;
297 case LPROPS_FRDI_IDX:
298 list_add(&lprops->list, &c->frdi_idx_list);
299 break;
300 default:
301 ubifs_assert(0);
302 }
303
304 lprops->flags &= ~LPROPS_CAT_MASK;
305 lprops->flags |= cat;
306 c->in_a_category_cnt += 1;
307 ubifs_assert(c->in_a_category_cnt <= c->main_lebs);
308}
309
310/**
311 * ubifs_remove_from_cat - remove LEB properties from a category list or heap.
312 * @c: UBIFS file-system description object
313 * @lprops: LEB properties to remove
314 * @cat: LEB category from which to remove
315 *
316 * LEB properties are categorized to enable fast find operations.
317 */
318static void ubifs_remove_from_cat(struct ubifs_info *c,
319 struct ubifs_lprops *lprops, int cat)
320{
321 switch (cat) {
322 case LPROPS_DIRTY:
323 case LPROPS_DIRTY_IDX:
324 case LPROPS_FREE:
325 remove_from_lpt_heap(c, lprops, cat);
326 break;
327 case LPROPS_FREEABLE:
328 c->freeable_cnt -= 1;
329 ubifs_assert(c->freeable_cnt >= 0);
330 /* Fall through */
331 case LPROPS_UNCAT:
332 case LPROPS_EMPTY:
333 case LPROPS_FRDI_IDX:
334 ubifs_assert(!list_empty(&lprops->list));
335 list_del(&lprops->list);
336 break;
337 default:
338 ubifs_assert(0);
339 }
340
341 c->in_a_category_cnt -= 1;
342 ubifs_assert(c->in_a_category_cnt >= 0);
343}
344
345/**
346 * ubifs_replace_cat - replace lprops in a category list or heap.
347 * @c: UBIFS file-system description object
348 * @old_lprops: LEB properties to replace
349 * @new_lprops: LEB properties with which to replace
350 *
351 * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
352 * and the lprops that the pnode contains. When that happens, references in
353 * category lists and heaps must be replaced. This function does that.
354 */
355void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
356 struct ubifs_lprops *new_lprops)
357{
358 int cat;
359
360 cat = new_lprops->flags & LPROPS_CAT_MASK;
361 switch (cat) {
362 case LPROPS_DIRTY:
363 case LPROPS_DIRTY_IDX:
364 case LPROPS_FREE:
365 lpt_heap_replace(c, old_lprops, new_lprops, cat);
366 break;
367 case LPROPS_UNCAT:
368 case LPROPS_EMPTY:
369 case LPROPS_FREEABLE:
370 case LPROPS_FRDI_IDX:
371 list_replace(&old_lprops->list, &new_lprops->list);
372 break;
373 default:
374 ubifs_assert(0);
375 }
376}
377
378/**
379 * ubifs_ensure_cat - ensure LEB properties are categorized.
380 * @c: UBIFS file-system description object
381 * @lprops: LEB properties
382 *
383 * A LEB may have fallen off of the bottom of a heap, and ended up as
384 * un-categorized even though it has enough space for us now. If that is the
385 * case this function will put the LEB back onto a heap.
386 */
387void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops)
388{
389 int cat = lprops->flags & LPROPS_CAT_MASK;
390
391 if (cat != LPROPS_UNCAT)
392 return;
393 cat = ubifs_categorize_lprops(c, lprops);
394 if (cat == LPROPS_UNCAT)
395 return;
396 ubifs_remove_from_cat(c, lprops, LPROPS_UNCAT);
397 ubifs_add_to_cat(c, lprops, cat);
398}
399
400/**
401 * ubifs_categorize_lprops - categorize LEB properties.
402 * @c: UBIFS file-system description object
403 * @lprops: LEB properties to categorize
404 *
405 * LEB properties are categorized to enable fast find operations. This function
406 * returns the LEB category to which the LEB properties belong. Note however
407 * that if the LEB category is stored as a heap and the heap is full, the
408 * LEB properties may have their category changed to %LPROPS_UNCAT.
409 */
410int ubifs_categorize_lprops(const struct ubifs_info *c,
411 const struct ubifs_lprops *lprops)
412{
413 if (lprops->flags & LPROPS_TAKEN)
414 return LPROPS_UNCAT;
415
416 if (lprops->free == c->leb_size) {
417 ubifs_assert(!(lprops->flags & LPROPS_INDEX));
418 return LPROPS_EMPTY;
419 }
420
421 if (lprops->free + lprops->dirty == c->leb_size) {
422 if (lprops->flags & LPROPS_INDEX)
423 return LPROPS_FRDI_IDX;
424 else
425 return LPROPS_FREEABLE;
426 }
427
428 if (lprops->flags & LPROPS_INDEX) {
429 if (lprops->dirty + lprops->free >= c->min_idx_node_sz)
430 return LPROPS_DIRTY_IDX;
431 } else {
432 if (lprops->dirty >= c->dead_wm &&
433 lprops->dirty > lprops->free)
434 return LPROPS_DIRTY;
435 if (lprops->free > 0)
436 return LPROPS_FREE;
437 }
438
439 return LPROPS_UNCAT;
440}
441
442/**
443 * change_category - change LEB properties category.
444 * @c: UBIFS file-system description object
445 * @lprops: LEB properties to re-categorize
446 *
447 * LEB properties are categorized to enable fast find operations. When the LEB
448 * properties change they must be re-categorized.
449 */
450static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops)
451{
452 int old_cat = lprops->flags & LPROPS_CAT_MASK;
453 int new_cat = ubifs_categorize_lprops(c, lprops);
454
455 if (old_cat == new_cat) {
456 struct ubifs_lpt_heap *heap;
457
458 /* lprops on a heap now must be moved up or down */
459 if (new_cat < 1 || new_cat > LPROPS_HEAP_CNT)
460 return; /* Not on a heap */
461 heap = &c->lpt_heap[new_cat - 1];
462 adjust_lpt_heap(c, heap, lprops, lprops->hpos, new_cat);
463 } else {
464 ubifs_remove_from_cat(c, lprops, old_cat);
465 ubifs_add_to_cat(c, lprops, new_cat);
466 }
467}
468
469/**
470 * ubifs_calc_dark - calculate LEB dark space size.
471 * @c: the UBIFS file-system description object
472 * @spc: amount of free and dirty space in the LEB
473 *
474 * This function calculates and returns amount of dark space in an LEB which
475 * has @spc bytes of free and dirty space.
476 *
477 * UBIFS is trying to account the space which might not be usable, and this
478 * space is called "dark space". For example, if an LEB has only %512 free
479 * bytes, it is dark space, because it cannot fit a large data node.
480 */
481int ubifs_calc_dark(const struct ubifs_info *c, int spc)
482{
483 ubifs_assert(!(spc & 7));
484
485 if (spc < c->dark_wm)
486 return spc;
487
488 /*
489 * If we have slightly more space then the dark space watermark, we can
490 * anyway safely assume it we'll be able to write a node of the
491 * smallest size there.
492 */
493 if (spc - c->dark_wm < MIN_WRITE_SZ)
494 return spc - MIN_WRITE_SZ;
495
496 return c->dark_wm;
497}
498
499/**
500 * is_lprops_dirty - determine if LEB properties are dirty.
501 * @c: the UBIFS file-system description object
502 * @lprops: LEB properties to test
503 */
504static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops)
505{
506 struct ubifs_pnode *pnode;
507 int pos;
508
509 pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1);
510 pnode = (struct ubifs_pnode *)container_of(lprops - pos,
511 struct ubifs_pnode,
512 lprops[0]);
513 return !test_bit(COW_CNODE, &pnode->flags) &&
514 test_bit(DIRTY_CNODE, &pnode->flags);
515}
516
517/**
518 * ubifs_change_lp - change LEB properties.
519 * @c: the UBIFS file-system description object
520 * @lp: LEB properties to change
521 * @free: new free space amount
522 * @dirty: new dirty space amount
523 * @flags: new flags
524 * @idx_gc_cnt: change to the count of @idx_gc list
525 *
526 * This function changes LEB properties (@free, @dirty or @flag). However, the
527 * property which has the %LPROPS_NC value is not changed. Returns a pointer to
528 * the updated LEB properties on success and a negative error code on failure.
529 *
530 * Note, the LEB properties may have had to be copied (due to COW) and
531 * consequently the pointer returned may not be the same as the pointer
532 * passed.
533 */
534const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
535 const struct ubifs_lprops *lp,
536 int free, int dirty, int flags,
537 int idx_gc_cnt)
538{
539 /*
540 * This is the only function that is allowed to change lprops, so we
541 * discard the "const" qualifier.
542 */
543 struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp;
544
545 dbg_lp("LEB %d, free %d, dirty %d, flags %d",
546 lprops->lnum, free, dirty, flags);
547
548 ubifs_assert(mutex_is_locked(&c->lp_mutex));
549 ubifs_assert(c->lst.empty_lebs >= 0 &&
550 c->lst.empty_lebs <= c->main_lebs);
551 ubifs_assert(c->freeable_cnt >= 0);
552 ubifs_assert(c->freeable_cnt <= c->main_lebs);
553 ubifs_assert(c->lst.taken_empty_lebs >= 0);
554 ubifs_assert(c->lst.taken_empty_lebs <= c->lst.empty_lebs);
555 ubifs_assert(!(c->lst.total_free & 7) && !(c->lst.total_dirty & 7));
556 ubifs_assert(!(c->lst.total_dead & 7) && !(c->lst.total_dark & 7));
557 ubifs_assert(!(c->lst.total_used & 7));
558 ubifs_assert(free == LPROPS_NC || free >= 0);
559 ubifs_assert(dirty == LPROPS_NC || dirty >= 0);
560
561 if (!is_lprops_dirty(c, lprops)) {
562 lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum);
563 if (IS_ERR(lprops))
564 return lprops;
565 } else
566 ubifs_assert(lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum));
567
568 ubifs_assert(!(lprops->free & 7) && !(lprops->dirty & 7));
569
570 spin_lock(&c->space_lock);
571 if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
572 c->lst.taken_empty_lebs -= 1;
573
574 if (!(lprops->flags & LPROPS_INDEX)) {
575 int old_spc;
576
577 old_spc = lprops->free + lprops->dirty;
578 if (old_spc < c->dead_wm)
579 c->lst.total_dead -= old_spc;
580 else
581 c->lst.total_dark -= ubifs_calc_dark(c, old_spc);
582
583 c->lst.total_used -= c->leb_size - old_spc;
584 }
585
586 if (free != LPROPS_NC) {
587 free = ALIGN(free, 8);
588 c->lst.total_free += free - lprops->free;
589
590 /* Increase or decrease empty LEBs counter if needed */
591 if (free == c->leb_size) {
592 if (lprops->free != c->leb_size)
593 c->lst.empty_lebs += 1;
594 } else if (lprops->free == c->leb_size)
595 c->lst.empty_lebs -= 1;
596 lprops->free = free;
597 }
598
599 if (dirty != LPROPS_NC) {
600 dirty = ALIGN(dirty, 8);
601 c->lst.total_dirty += dirty - lprops->dirty;
602 lprops->dirty = dirty;
603 }
604
605 if (flags != LPROPS_NC) {
606 /* Take care about indexing LEBs counter if needed */
607 if ((lprops->flags & LPROPS_INDEX)) {
608 if (!(flags & LPROPS_INDEX))
609 c->lst.idx_lebs -= 1;
610 } else if (flags & LPROPS_INDEX)
611 c->lst.idx_lebs += 1;
612 lprops->flags = flags;
613 }
614
615 if (!(lprops->flags & LPROPS_INDEX)) {
616 int new_spc;
617
618 new_spc = lprops->free + lprops->dirty;
619 if (new_spc < c->dead_wm)
620 c->lst.total_dead += new_spc;
621 else
622 c->lst.total_dark += ubifs_calc_dark(c, new_spc);
623
624 c->lst.total_used += c->leb_size - new_spc;
625 }
626
627 if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
628 c->lst.taken_empty_lebs += 1;
629
630 change_category(c, lprops);
631 c->idx_gc_cnt += idx_gc_cnt;
632 spin_unlock(&c->space_lock);
633 return lprops;
634}
635
636/**
637 * ubifs_get_lp_stats - get lprops statistics.
638 * @c: UBIFS file-system description object
639 * @lst: return statistics
640 */
641void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *lst)
642{
643 spin_lock(&c->space_lock);
644 memcpy(lst, &c->lst, sizeof(struct ubifs_lp_stats));
645 spin_unlock(&c->space_lock);
646}
647
648/**
649 * ubifs_change_one_lp - change LEB properties.
650 * @c: the UBIFS file-system description object
651 * @lnum: LEB to change properties for
652 * @free: amount of free space
653 * @dirty: amount of dirty space
654 * @flags_set: flags to set
655 * @flags_clean: flags to clean
656 * @idx_gc_cnt: change to the count of idx_gc list
657 *
658 * This function changes properties of LEB @lnum. It is a helper wrapper over
659 * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the
660 * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and
661 * a negative error code in case of failure.
662 */
663int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
664 int flags_set, int flags_clean, int idx_gc_cnt)
665{
666 int err = 0, flags;
667 const struct ubifs_lprops *lp;
668
669 ubifs_get_lprops(c);
670
671 lp = ubifs_lpt_lookup_dirty(c, lnum);
672 if (IS_ERR(lp)) {
673 err = PTR_ERR(lp);
674 goto out;
675 }
676
677 flags = (lp->flags | flags_set) & ~flags_clean;
678 lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt);
679 if (IS_ERR(lp))
680 err = PTR_ERR(lp);
681
682out:
683 ubifs_release_lprops(c);
684 if (err)
685 ubifs_err(c, "cannot change properties of LEB %d, error %d",
686 lnum, err);
687 return err;
688}
689
690/**
691 * ubifs_update_one_lp - update LEB properties.
692 * @c: the UBIFS file-system description object
693 * @lnum: LEB to change properties for
694 * @free: amount of free space
695 * @dirty: amount of dirty space to add
696 * @flags_set: flags to set
697 * @flags_clean: flags to clean
698 *
699 * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to
700 * current dirty space, not substitutes it.
701 */
702int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
703 int flags_set, int flags_clean)
704{
705 int err = 0, flags;
706 const struct ubifs_lprops *lp;
707
708 ubifs_get_lprops(c);
709
710 lp = ubifs_lpt_lookup_dirty(c, lnum);
711 if (IS_ERR(lp)) {
712 err = PTR_ERR(lp);
713 goto out;
714 }
715
716 flags = (lp->flags | flags_set) & ~flags_clean;
717 lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0);
718 if (IS_ERR(lp))
719 err = PTR_ERR(lp);
720
721out:
722 ubifs_release_lprops(c);
723 if (err)
724 ubifs_err(c, "cannot update properties of LEB %d, error %d",
725 lnum, err);
726 return err;
727}
728
729/**
730 * ubifs_read_one_lp - read LEB properties.
731 * @c: the UBIFS file-system description object
732 * @lnum: LEB to read properties for
733 * @lp: where to store read properties
734 *
735 * This helper function reads properties of a LEB @lnum and stores them in @lp.
736 * Returns zero in case of success and a negative error code in case of
737 * failure.
738 */
739int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp)
740{
741 int err = 0;
742 const struct ubifs_lprops *lpp;
743
744 ubifs_get_lprops(c);
745
746 lpp = ubifs_lpt_lookup(c, lnum);
747 if (IS_ERR(lpp)) {
748 err = PTR_ERR(lpp);
749 ubifs_err(c, "cannot read properties of LEB %d, error %d",
750 lnum, err);
751 goto out;
752 }
753
754 memcpy(lp, lpp, sizeof(struct ubifs_lprops));
755
756out:
757 ubifs_release_lprops(c);
758 return err;
759}
760
761/**
762 * ubifs_fast_find_free - try to find a LEB with free space quickly.
763 * @c: the UBIFS file-system description object
764 *
765 * This function returns LEB properties for a LEB with free space or %NULL if
766 * the function is unable to find a LEB quickly.
767 */
768const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c)
769{
770 struct ubifs_lprops *lprops;
771 struct ubifs_lpt_heap *heap;
772
773 ubifs_assert(mutex_is_locked(&c->lp_mutex));
774
775 heap = &c->lpt_heap[LPROPS_FREE - 1];
776 if (heap->cnt == 0)
777 return NULL;
778
779 lprops = heap->arr[0];
780 ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
781 ubifs_assert(!(lprops->flags & LPROPS_INDEX));
782 return lprops;
783}
784
785/**
786 * ubifs_fast_find_empty - try to find an empty LEB quickly.
787 * @c: the UBIFS file-system description object
788 *
789 * This function returns LEB properties for an empty LEB or %NULL if the
790 * function is unable to find an empty LEB quickly.
791 */
792const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c)
793{
794 struct ubifs_lprops *lprops;
795
796 ubifs_assert(mutex_is_locked(&c->lp_mutex));
797
798 if (list_empty(&c->empty_list))
799 return NULL;
800
801 lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list);
802 ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
803 ubifs_assert(!(lprops->flags & LPROPS_INDEX));
804 ubifs_assert(lprops->free == c->leb_size);
805 return lprops;
806}
807
808/**
809 * ubifs_fast_find_freeable - try to find a freeable LEB quickly.
810 * @c: the UBIFS file-system description object
811 *
812 * This function returns LEB properties for a freeable LEB or %NULL if the
813 * function is unable to find a freeable LEB quickly.
814 */
815const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c)
816{
817 struct ubifs_lprops *lprops;
818
819 ubifs_assert(mutex_is_locked(&c->lp_mutex));
820
821 if (list_empty(&c->freeable_list))
822 return NULL;
823
824 lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list);
825 ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
826 ubifs_assert(!(lprops->flags & LPROPS_INDEX));
827 ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
828 ubifs_assert(c->freeable_cnt > 0);
829 return lprops;
830}
831
832/**
833 * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly.
834 * @c: the UBIFS file-system description object
835 *
836 * This function returns LEB properties for a freeable index LEB or %NULL if the
837 * function is unable to find a freeable index LEB quickly.
838 */
839const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c)
840{
841 struct ubifs_lprops *lprops;
842
843 ubifs_assert(mutex_is_locked(&c->lp_mutex));
844
845 if (list_empty(&c->frdi_idx_list))
846 return NULL;
847
848 lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list);
849 ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
850 ubifs_assert((lprops->flags & LPROPS_INDEX));
851 ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
852 return lprops;
853}
854
855/*
856 * Everything below is related to debugging.
857 */
858
859/**
860 * dbg_check_cats - check category heaps and lists.
861 * @c: UBIFS file-system description object
862 *
863 * This function returns %0 on success and a negative error code on failure.
864 */
865int dbg_check_cats(struct ubifs_info *c)
866{
867 struct ubifs_lprops *lprops;
868 struct list_head *pos;
869 int i, cat;
870
871 if (!dbg_is_chk_gen(c) && !dbg_is_chk_lprops(c))
872 return 0;
873
874 list_for_each_entry(lprops, &c->empty_list, list) {
875 if (lprops->free != c->leb_size) {
876 ubifs_err(c, "non-empty LEB %d on empty list (free %d dirty %d flags %d)",
877 lprops->lnum, lprops->free, lprops->dirty,
878 lprops->flags);
879 return -EINVAL;
880 }
881 if (lprops->flags & LPROPS_TAKEN) {
882 ubifs_err(c, "taken LEB %d on empty list (free %d dirty %d flags %d)",
883 lprops->lnum, lprops->free, lprops->dirty,
884 lprops->flags);
885 return -EINVAL;
886 }
887 }
888
889 i = 0;
890 list_for_each_entry(lprops, &c->freeable_list, list) {
891 if (lprops->free + lprops->dirty != c->leb_size) {
892 ubifs_err(c, "non-freeable LEB %d on freeable list (free %d dirty %d flags %d)",
893 lprops->lnum, lprops->free, lprops->dirty,
894 lprops->flags);
895 return -EINVAL;
896 }
897 if (lprops->flags & LPROPS_TAKEN) {
898 ubifs_err(c, "taken LEB %d on freeable list (free %d dirty %d flags %d)",
899 lprops->lnum, lprops->free, lprops->dirty,
900 lprops->flags);
901 return -EINVAL;
902 }
903 i += 1;
904 }
905 if (i != c->freeable_cnt) {
906 ubifs_err(c, "freeable list count %d expected %d", i,
907 c->freeable_cnt);
908 return -EINVAL;
909 }
910
911 i = 0;
912 list_for_each(pos, &c->idx_gc)
913 i += 1;
914 if (i != c->idx_gc_cnt) {
915 ubifs_err(c, "idx_gc list count %d expected %d", i,
916 c->idx_gc_cnt);
917 return -EINVAL;
918 }
919
920 list_for_each_entry(lprops, &c->frdi_idx_list, list) {
921 if (lprops->free + lprops->dirty != c->leb_size) {
922 ubifs_err(c, "non-freeable LEB %d on frdi_idx list (free %d dirty %d flags %d)",
923 lprops->lnum, lprops->free, lprops->dirty,
924 lprops->flags);
925 return -EINVAL;
926 }
927 if (lprops->flags & LPROPS_TAKEN) {
928 ubifs_err(c, "taken LEB %d on frdi_idx list (free %d dirty %d flags %d)",
929 lprops->lnum, lprops->free, lprops->dirty,
930 lprops->flags);
931 return -EINVAL;
932 }
933 if (!(lprops->flags & LPROPS_INDEX)) {
934 ubifs_err(c, "non-index LEB %d on frdi_idx list (free %d dirty %d flags %d)",
935 lprops->lnum, lprops->free, lprops->dirty,
936 lprops->flags);
937 return -EINVAL;
938 }
939 }
940
941 for (cat = 1; cat <= LPROPS_HEAP_CNT; cat++) {
942 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
943
944 for (i = 0; i < heap->cnt; i++) {
945 lprops = heap->arr[i];
946 if (!lprops) {
947 ubifs_err(c, "null ptr in LPT heap cat %d", cat);
948 return -EINVAL;
949 }
950 if (lprops->hpos != i) {
951 ubifs_err(c, "bad ptr in LPT heap cat %d", cat);
952 return -EINVAL;
953 }
954 if (lprops->flags & LPROPS_TAKEN) {
955 ubifs_err(c, "taken LEB in LPT heap cat %d", cat);
956 return -EINVAL;
957 }
958 }
959 }
960
961 return 0;
962}
963
964void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
965 int add_pos)
966{
967 int i = 0, j, err = 0;
968
969 if (!dbg_is_chk_gen(c) && !dbg_is_chk_lprops(c))
970 return;
971
972 for (i = 0; i < heap->cnt; i++) {
973 struct ubifs_lprops *lprops = heap->arr[i];
974 struct ubifs_lprops *lp;
975
976 if (i != add_pos)
977 if ((lprops->flags & LPROPS_CAT_MASK) != cat) {
978 err = 1;
979 goto out;
980 }
981 if (lprops->hpos != i) {
982 err = 2;
983 goto out;
984 }
985 lp = ubifs_lpt_lookup(c, lprops->lnum);
986 if (IS_ERR(lp)) {
987 err = 3;
988 goto out;
989 }
990 if (lprops != lp) {
991 ubifs_err(c, "lprops %zx lp %zx lprops->lnum %d lp->lnum %d",
992 (size_t)lprops, (size_t)lp, lprops->lnum,
993 lp->lnum);
994 err = 4;
995 goto out;
996 }
997 for (j = 0; j < i; j++) {
998 lp = heap->arr[j];
999 if (lp == lprops) {
1000 err = 5;
1001 goto out;
1002 }
1003 if (lp->lnum == lprops->lnum) {
1004 err = 6;
1005 goto out;
1006 }
1007 }
1008 }
1009out:
1010 if (err) {
1011 ubifs_err(c, "failed cat %d hpos %d err %d", cat, i, err);
1012 dump_stack();
1013 ubifs_dump_heap(c, heap, cat);
1014 }
1015}
1016
1017/**
1018 * scan_check_cb - scan callback.
1019 * @c: the UBIFS file-system description object
1020 * @lp: LEB properties to scan
1021 * @in_tree: whether the LEB properties are in main memory
1022 * @lst: lprops statistics to update
1023 *
1024 * This function returns a code that indicates whether the scan should continue
1025 * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
1026 * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
1027 * (%LPT_SCAN_STOP).
1028 */
1029static int scan_check_cb(struct ubifs_info *c,
1030 const struct ubifs_lprops *lp, int in_tree,
1031 struct ubifs_lp_stats *lst)
1032{
1033 struct ubifs_scan_leb *sleb;
1034 struct ubifs_scan_node *snod;
1035 int cat, lnum = lp->lnum, is_idx = 0, used = 0, free, dirty, ret;
1036 void *buf = NULL;
1037
1038 cat = lp->flags & LPROPS_CAT_MASK;
1039 if (cat != LPROPS_UNCAT) {
1040 cat = ubifs_categorize_lprops(c, lp);
1041 if (cat != (lp->flags & LPROPS_CAT_MASK)) {
1042 ubifs_err(c, "bad LEB category %d expected %d",
1043 (lp->flags & LPROPS_CAT_MASK), cat);
1044 return -EINVAL;
1045 }
1046 }
1047
1048 /* Check lp is on its category list (if it has one) */
1049 if (in_tree) {
1050 struct list_head *list = NULL;
1051
1052 switch (cat) {
1053 case LPROPS_EMPTY:
1054 list = &c->empty_list;
1055 break;
1056 case LPROPS_FREEABLE:
1057 list = &c->freeable_list;
1058 break;
1059 case LPROPS_FRDI_IDX:
1060 list = &c->frdi_idx_list;
1061 break;
1062 case LPROPS_UNCAT:
1063 list = &c->uncat_list;
1064 break;
1065 }
1066 if (list) {
1067 struct ubifs_lprops *lprops;
1068 int found = 0;
1069
1070 list_for_each_entry(lprops, list, list) {
1071 if (lprops == lp) {
1072 found = 1;
1073 break;
1074 }
1075 }
1076 if (!found) {
1077 ubifs_err(c, "bad LPT list (category %d)", cat);
1078 return -EINVAL;
1079 }
1080 }
1081 }
1082
1083 /* Check lp is on its category heap (if it has one) */
1084 if (in_tree && cat > 0 && cat <= LPROPS_HEAP_CNT) {
1085 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
1086
1087 if ((lp->hpos != -1 && heap->arr[lp->hpos]->lnum != lnum) ||
1088 lp != heap->arr[lp->hpos]) {
1089 ubifs_err(c, "bad LPT heap (category %d)", cat);
1090 return -EINVAL;
1091 }
1092 }
1093
1094 buf = __vmalloc(c->leb_size, GFP_NOFS, PAGE_KERNEL);
1095 if (!buf)
1096 return -ENOMEM;
1097
1098 /*
1099 * After an unclean unmount, empty and freeable LEBs
1100 * may contain garbage - do not scan them.
1101 */
1102 if (lp->free == c->leb_size) {
1103 lst->empty_lebs += 1;
1104 lst->total_free += c->leb_size;
1105 lst->total_dark += ubifs_calc_dark(c, c->leb_size);
1106 return LPT_SCAN_CONTINUE;
1107 }
1108 if (lp->free + lp->dirty == c->leb_size &&
1109 !(lp->flags & LPROPS_INDEX)) {
1110 lst->total_free += lp->free;
1111 lst->total_dirty += lp->dirty;
1112 lst->total_dark += ubifs_calc_dark(c, c->leb_size);
1113 return LPT_SCAN_CONTINUE;
1114 }
1115
1116 sleb = ubifs_scan(c, lnum, 0, buf, 0);
1117 if (IS_ERR(sleb)) {
1118 ret = PTR_ERR(sleb);
1119 if (ret == -EUCLEAN) {
1120 ubifs_dump_lprops(c);
1121 ubifs_dump_budg(c, &c->bi);
1122 }
1123 goto out;
1124 }
1125
1126 is_idx = -1;
1127 list_for_each_entry(snod, &sleb->nodes, list) {
1128 int found, level = 0;
1129
1130 cond_resched();
1131
1132 if (is_idx == -1)
1133 is_idx = (snod->type == UBIFS_IDX_NODE) ? 1 : 0;
1134
1135 if (is_idx && snod->type != UBIFS_IDX_NODE) {
1136 ubifs_err(c, "indexing node in data LEB %d:%d",
1137 lnum, snod->offs);
1138 goto out_destroy;
1139 }
1140
1141 if (snod->type == UBIFS_IDX_NODE) {
1142 struct ubifs_idx_node *idx = snod->node;
1143
1144 key_read(c, ubifs_idx_key(c, idx), &snod->key);
1145 level = le16_to_cpu(idx->level);
1146 }
1147
1148 found = ubifs_tnc_has_node(c, &snod->key, level, lnum,
1149 snod->offs, is_idx);
1150 if (found) {
1151 if (found < 0)
1152 goto out_destroy;
1153 used += ALIGN(snod->len, 8);
1154 }
1155 }
1156
1157 free = c->leb_size - sleb->endpt;
1158 dirty = sleb->endpt - used;
1159
1160 if (free > c->leb_size || free < 0 || dirty > c->leb_size ||
1161 dirty < 0) {
1162 ubifs_err(c, "bad calculated accounting for LEB %d: free %d, dirty %d",
1163 lnum, free, dirty);
1164 goto out_destroy;
1165 }
1166
1167 if (lp->free + lp->dirty == c->leb_size &&
1168 free + dirty == c->leb_size)
1169 if ((is_idx && !(lp->flags & LPROPS_INDEX)) ||
1170 (!is_idx && free == c->leb_size) ||
1171 lp->free == c->leb_size) {
1172 /*
1173 * Empty or freeable LEBs could contain index
1174 * nodes from an uncompleted commit due to an
1175 * unclean unmount. Or they could be empty for
1176 * the same reason. Or it may simply not have been
1177 * unmapped.
1178 */
1179 free = lp->free;
1180 dirty = lp->dirty;
1181 is_idx = 0;
1182 }
1183
1184 if (is_idx && lp->free + lp->dirty == free + dirty &&
1185 lnum != c->ihead_lnum) {
1186 /*
1187 * After an unclean unmount, an index LEB could have a different
1188 * amount of free space than the value recorded by lprops. That
1189 * is because the in-the-gaps method may use free space or
1190 * create free space (as a side-effect of using ubi_leb_change
1191 * and not writing the whole LEB). The incorrect free space
1192 * value is not a problem because the index is only ever
1193 * allocated empty LEBs, so there will never be an attempt to
1194 * write to the free space at the end of an index LEB - except
1195 * by the in-the-gaps method for which it is not a problem.
1196 */
1197 free = lp->free;
1198 dirty = lp->dirty;
1199 }
1200
1201 if (lp->free != free || lp->dirty != dirty)
1202 goto out_print;
1203
1204 if (is_idx && !(lp->flags & LPROPS_INDEX)) {
1205 if (free == c->leb_size)
1206 /* Free but not unmapped LEB, it's fine */
1207 is_idx = 0;
1208 else {
1209 ubifs_err(c, "indexing node without indexing flag");
1210 goto out_print;
1211 }
1212 }
1213
1214 if (!is_idx && (lp->flags & LPROPS_INDEX)) {
1215 ubifs_err(c, "data node with indexing flag");
1216 goto out_print;
1217 }
1218
1219 if (free == c->leb_size)
1220 lst->empty_lebs += 1;
1221
1222 if (is_idx)
1223 lst->idx_lebs += 1;
1224
1225 if (!(lp->flags & LPROPS_INDEX))
1226 lst->total_used += c->leb_size - free - dirty;
1227 lst->total_free += free;
1228 lst->total_dirty += dirty;
1229
1230 if (!(lp->flags & LPROPS_INDEX)) {
1231 int spc = free + dirty;
1232
1233 if (spc < c->dead_wm)
1234 lst->total_dead += spc;
1235 else
1236 lst->total_dark += ubifs_calc_dark(c, spc);
1237 }
1238
1239 ubifs_scan_destroy(sleb);
1240 vfree(buf);
1241 return LPT_SCAN_CONTINUE;
1242
1243out_print:
1244 ubifs_err(c, "bad accounting of LEB %d: free %d, dirty %d flags %#x, should be free %d, dirty %d",
1245 lnum, lp->free, lp->dirty, lp->flags, free, dirty);
1246 ubifs_dump_leb(c, lnum);
1247out_destroy:
1248 ubifs_scan_destroy(sleb);
1249 ret = -EINVAL;
1250out:
1251 vfree(buf);
1252 return ret;
1253}
1254
1255/**
1256 * dbg_check_lprops - check all LEB properties.
1257 * @c: UBIFS file-system description object
1258 *
1259 * This function checks all LEB properties and makes sure they are all correct.
1260 * It returns zero if everything is fine, %-EINVAL if there is an inconsistency
1261 * and other negative error codes in case of other errors. This function is
1262 * called while the file system is locked (because of commit start), so no
1263 * additional locking is required. Note that locking the LPT mutex would cause
1264 * a circular lock dependency with the TNC mutex.
1265 */
1266int dbg_check_lprops(struct ubifs_info *c)
1267{
1268 int i, err;
1269 struct ubifs_lp_stats lst;
1270
1271 if (!dbg_is_chk_lprops(c))
1272 return 0;
1273
1274 /*
1275 * As we are going to scan the media, the write buffers have to be
1276 * synchronized.
1277 */
1278 for (i = 0; i < c->jhead_cnt; i++) {
1279 err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
1280 if (err)
1281 return err;
1282 }
1283
1284 memset(&lst, 0, sizeof(struct ubifs_lp_stats));
1285 err = ubifs_lpt_scan_nolock(c, c->main_first, c->leb_cnt - 1,
1286 (ubifs_lpt_scan_callback)scan_check_cb,
1287 &lst);
1288 if (err && err != -ENOSPC)
1289 goto out;
1290
1291 if (lst.empty_lebs != c->lst.empty_lebs ||
1292 lst.idx_lebs != c->lst.idx_lebs ||
1293 lst.total_free != c->lst.total_free ||
1294 lst.total_dirty != c->lst.total_dirty ||
1295 lst.total_used != c->lst.total_used) {
1296 ubifs_err(c, "bad overall accounting");
1297 ubifs_err(c, "calculated: empty_lebs %d, idx_lebs %d, total_free %lld, total_dirty %lld, total_used %lld",
1298 lst.empty_lebs, lst.idx_lebs, lst.total_free,
1299 lst.total_dirty, lst.total_used);
1300 ubifs_err(c, "read from lprops: empty_lebs %d, idx_lebs %d, total_free %lld, total_dirty %lld, total_used %lld",
1301 c->lst.empty_lebs, c->lst.idx_lebs, c->lst.total_free,
1302 c->lst.total_dirty, c->lst.total_used);
1303 err = -EINVAL;
1304 goto out;
1305 }
1306
1307 if (lst.total_dead != c->lst.total_dead ||
1308 lst.total_dark != c->lst.total_dark) {
1309 ubifs_err(c, "bad dead/dark space accounting");
1310 ubifs_err(c, "calculated: total_dead %lld, total_dark %lld",
1311 lst.total_dead, lst.total_dark);
1312 ubifs_err(c, "read from lprops: total_dead %lld, total_dark %lld",
1313 c->lst.total_dead, c->lst.total_dark);
1314 err = -EINVAL;
1315 goto out;
1316 }
1317
1318 err = dbg_check_cats(c);
1319out:
1320 return err;
1321}