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 */
26 static 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 */
50 static 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 */
87 static 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 */
166 static 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 */
214 static 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 */
243 static 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 */
261 void 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 fallthrough;
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 */
304 static 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 fallthrough;
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 */
341 void 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 */
373 void 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 */
396 int 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 */
436 static 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 */
467 int 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 */
490 static 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 */
520 const 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 */
627 void 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 */
649 int 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
668 out:
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 */
688 int 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
707 out:
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 */
725 int 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
742 out:
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 */
754 const 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 */
778 const 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 */
801 const 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 */
825 const 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 */
851 int 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
950 void 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 }
995 out:
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 * @arg: 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 */
1015 static int scan_check_cb(struct ubifs_info *c,
1016 const struct ubifs_lprops *lp, int in_tree,
1017 void *arg)
1018 {
1019 struct ubifs_lp_stats *lst = arg;
1020 struct ubifs_scan_leb *sleb;
1021 struct ubifs_scan_node *snod;
1022 int cat, lnum = lp->lnum, is_idx = 0, used = 0, free, dirty, ret;
1023 void *buf = NULL;
1024
1025 cat = lp->flags & LPROPS_CAT_MASK;
1026 if (cat != LPROPS_UNCAT) {
1027 cat = ubifs_categorize_lprops(c, lp);
1028 if (cat != (lp->flags & LPROPS_CAT_MASK)) {
1029 ubifs_err(c, "bad LEB category %d expected %d",
1030 (lp->flags & LPROPS_CAT_MASK), cat);
1031 return -EINVAL;
1032 }
1033 }
1034
1035 /* Check lp is on its category list (if it has one) */
1036 if (in_tree) {
1037 struct list_head *list = NULL;
1038
1039 switch (cat) {
1040 case LPROPS_EMPTY:
1041 list = &c->empty_list;
1042 break;
1043 case LPROPS_FREEABLE:
1044 list = &c->freeable_list;
1045 break;
1046 case LPROPS_FRDI_IDX:
1047 list = &c->frdi_idx_list;
1048 break;
1049 case LPROPS_UNCAT:
1050 list = &c->uncat_list;
1051 break;
1052 }
1053 if (list) {
1054 struct ubifs_lprops *lprops;
1055 int found = 0;
1056
1057 list_for_each_entry(lprops, list, list) {
1058 if (lprops == lp) {
1059 found = 1;
1060 break;
1061 }
1062 }
1063 if (!found) {
1064 ubifs_err(c, "bad LPT list (category %d)", cat);
1065 return -EINVAL;
1066 }
1067 }
1068 }
1069
1070 /* Check lp is on its category heap (if it has one) */
1071 if (in_tree && cat > 0 && cat <= LPROPS_HEAP_CNT) {
1072 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
1073
1074 if ((lp->hpos != -1 && heap->arr[lp->hpos]->lnum != lnum) ||
1075 lp != heap->arr[lp->hpos]) {
1076 ubifs_err(c, "bad LPT heap (category %d)", cat);
1077 return -EINVAL;
1078 }
1079 }
1080
1081 /*
1082 * After an unclean unmount, empty and freeable LEBs
1083 * may contain garbage - do not scan them.
1084 */
1085 if (lp->free == c->leb_size) {
1086 lst->empty_lebs += 1;
1087 lst->total_free += c->leb_size;
1088 lst->total_dark += ubifs_calc_dark(c, c->leb_size);
1089 return LPT_SCAN_CONTINUE;
1090 }
1091 if (lp->free + lp->dirty == c->leb_size &&
1092 !(lp->flags & LPROPS_INDEX)) {
1093 lst->total_free += lp->free;
1094 lst->total_dirty += lp->dirty;
1095 lst->total_dark += ubifs_calc_dark(c, c->leb_size);
1096 return LPT_SCAN_CONTINUE;
1097 }
1098
1099 buf = __vmalloc(c->leb_size, GFP_NOFS);
1100 if (!buf)
1101 return -ENOMEM;
1102
1103 sleb = ubifs_scan(c, lnum, 0, buf, 0);
1104 if (IS_ERR(sleb)) {
1105 ret = PTR_ERR(sleb);
1106 if (ret == -EUCLEAN) {
1107 ubifs_dump_lprops(c);
1108 ubifs_dump_budg(c, &c->bi);
1109 }
1110 goto out;
1111 }
1112
1113 is_idx = -1;
1114 list_for_each_entry(snod, &sleb->nodes, list) {
1115 int found, level = 0;
1116
1117 cond_resched();
1118
1119 if (is_idx == -1)
1120 is_idx = (snod->type == UBIFS_IDX_NODE) ? 1 : 0;
1121
1122 if (is_idx && snod->type != UBIFS_IDX_NODE) {
1123 ubifs_err(c, "indexing node in data LEB %d:%d",
1124 lnum, snod->offs);
1125 goto out_destroy;
1126 }
1127
1128 if (snod->type == UBIFS_IDX_NODE) {
1129 struct ubifs_idx_node *idx = snod->node;
1130
1131 key_read(c, ubifs_idx_key(c, idx), &snod->key);
1132 level = le16_to_cpu(idx->level);
1133 }
1134
1135 found = ubifs_tnc_has_node(c, &snod->key, level, lnum,
1136 snod->offs, is_idx);
1137 if (found) {
1138 if (found < 0)
1139 goto out_destroy;
1140 used += ALIGN(snod->len, 8);
1141 }
1142 }
1143
1144 free = c->leb_size - sleb->endpt;
1145 dirty = sleb->endpt - used;
1146
1147 if (free > c->leb_size || free < 0 || dirty > c->leb_size ||
1148 dirty < 0) {
1149 ubifs_err(c, "bad calculated accounting for LEB %d: free %d, dirty %d",
1150 lnum, free, dirty);
1151 goto out_destroy;
1152 }
1153
1154 if (lp->free + lp->dirty == c->leb_size &&
1155 free + dirty == c->leb_size)
1156 if ((is_idx && !(lp->flags & LPROPS_INDEX)) ||
1157 (!is_idx && free == c->leb_size) ||
1158 lp->free == c->leb_size) {
1159 /*
1160 * Empty or freeable LEBs could contain index
1161 * nodes from an uncompleted commit due to an
1162 * unclean unmount. Or they could be empty for
1163 * the same reason. Or it may simply not have been
1164 * unmapped.
1165 */
1166 free = lp->free;
1167 dirty = lp->dirty;
1168 is_idx = 0;
1169 }
1170
1171 if (is_idx && lp->free + lp->dirty == free + dirty &&
1172 lnum != c->ihead_lnum) {
1173 /*
1174 * After an unclean unmount, an index LEB could have a different
1175 * amount of free space than the value recorded by lprops. That
1176 * is because the in-the-gaps method may use free space or
1177 * create free space (as a side-effect of using ubi_leb_change
1178 * and not writing the whole LEB). The incorrect free space
1179 * value is not a problem because the index is only ever
1180 * allocated empty LEBs, so there will never be an attempt to
1181 * write to the free space at the end of an index LEB - except
1182 * by the in-the-gaps method for which it is not a problem.
1183 */
1184 free = lp->free;
1185 dirty = lp->dirty;
1186 }
1187
1188 if (lp->free != free || lp->dirty != dirty)
1189 goto out_print;
1190
1191 if (is_idx && !(lp->flags & LPROPS_INDEX)) {
1192 if (free == c->leb_size)
1193 /* Free but not unmapped LEB, it's fine */
1194 is_idx = 0;
1195 else {
1196 ubifs_err(c, "indexing node without indexing flag");
1197 goto out_print;
1198 }
1199 }
1200
1201 if (!is_idx && (lp->flags & LPROPS_INDEX)) {
1202 ubifs_err(c, "data node with indexing flag");
1203 goto out_print;
1204 }
1205
1206 if (free == c->leb_size)
1207 lst->empty_lebs += 1;
1208
1209 if (is_idx)
1210 lst->idx_lebs += 1;
1211
1212 if (!(lp->flags & LPROPS_INDEX))
1213 lst->total_used += c->leb_size - free - dirty;
1214 lst->total_free += free;
1215 lst->total_dirty += dirty;
1216
1217 if (!(lp->flags & LPROPS_INDEX)) {
1218 int spc = free + dirty;
1219
1220 if (spc < c->dead_wm)
1221 lst->total_dead += spc;
1222 else
1223 lst->total_dark += ubifs_calc_dark(c, spc);
1224 }
1225
1226 ubifs_scan_destroy(sleb);
1227 vfree(buf);
1228 return LPT_SCAN_CONTINUE;
1229
1230 out_print:
1231 ubifs_err(c, "bad accounting of LEB %d: free %d, dirty %d flags %#x, should be free %d, dirty %d",
1232 lnum, lp->free, lp->dirty, lp->flags, free, dirty);
1233 ubifs_dump_leb(c, lnum);
1234 out_destroy:
1235 ubifs_scan_destroy(sleb);
1236 ret = -EINVAL;
1237 out:
1238 vfree(buf);
1239 return ret;
1240 }
1241
1242 /**
1243 * dbg_check_lprops - check all LEB properties.
1244 * @c: UBIFS file-system description object
1245 *
1246 * This function checks all LEB properties and makes sure they are all correct.
1247 * It returns zero if everything is fine, %-EINVAL if there is an inconsistency
1248 * and other negative error codes in case of other errors. This function is
1249 * called while the file system is locked (because of commit start), so no
1250 * additional locking is required. Note that locking the LPT mutex would cause
1251 * a circular lock dependency with the TNC mutex.
1252 */
1253 int dbg_check_lprops(struct ubifs_info *c)
1254 {
1255 int i, err;
1256 struct ubifs_lp_stats lst;
1257
1258 if (!dbg_is_chk_lprops(c))
1259 return 0;
1260
1261 /*
1262 * As we are going to scan the media, the write buffers have to be
1263 * synchronized.
1264 */
1265 for (i = 0; i < c->jhead_cnt; i++) {
1266 err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
1267 if (err)
1268 return err;
1269 }
1270
1271 memset(&lst, 0, sizeof(struct ubifs_lp_stats));
1272 err = ubifs_lpt_scan_nolock(c, c->main_first, c->leb_cnt - 1,
1273 scan_check_cb, &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);
1305 out:
1306 return err;
1307 }
1308
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