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[linux/fpc-iii.git] / fs / ubifs / lprops.c
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1 /*
2 * This file is part of UBIFS.
4 * Copyright (C) 2006-2008 Nokia Corporation.
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.
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.
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
19 * Authors: Adrian Hunter
20 * Artem Bityutskiy (Битюцкий Артём)
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.
31 #include "ubifs.h"
33 /**
34 * get_heap_comp_val - get the LEB properties value for heap comparisons.
35 * @lprops: LEB properties
36 * @cat: LEB category
38 static int get_heap_comp_val(struct ubifs_lprops *lprops, int cat)
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;
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
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.
62 static void move_up_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
63 struct ubifs_lprops *lprops, int cat)
65 int val1, val2, hpos;
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;
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);
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
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.
99 static void adjust_lpt_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap,
100 struct ubifs_lprops *lprops, int hpos, int cat)
102 int val1, val2, val3, cpos;
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;
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 */
128 /* Not greater than parent, so compare to children */
129 while (1) {
130 /* Compare to left child */
131 cpos = hpos * 2 + 1;
132 if (cpos >= heap->cnt)
133 return;
134 val2 = get_heap_comp_val(heap->arr[cpos], cat);
135 if (val1 < val2) {
136 /* Less than left child, so promote biggest child */
137 if (cpos + 1 < heap->cnt) {
138 val3 = get_heap_comp_val(heap->arr[cpos + 1],
139 cat);
140 if (val3 > val2)
141 cpos += 1; /* Right child is bigger */
143 heap->arr[cpos]->hpos = hpos;
144 heap->arr[hpos] = heap->arr[cpos];
145 heap->arr[cpos] = lprops;
146 lprops->hpos = cpos;
147 hpos = cpos;
148 continue;
150 /* Compare to right child */
151 cpos += 1;
152 if (cpos >= heap->cnt)
153 return;
154 val3 = get_heap_comp_val(heap->arr[cpos], cat);
155 if (val1 < val3) {
156 /* Less than right child, so promote right child */
157 heap->arr[cpos]->hpos = hpos;
158 heap->arr[hpos] = heap->arr[cpos];
159 heap->arr[cpos] = lprops;
160 lprops->hpos = cpos;
161 hpos = cpos;
162 continue;
164 return;
169 * add_to_lpt_heap - add LEB properties to a LEB category heap.
170 * @c: UBIFS file-system description object
171 * @lprops: LEB properties to add
172 * @cat: LEB category
174 * This function returns %1 if @lprops is added to the heap for LEB category
175 * @cat, otherwise %0 is returned because the heap is full.
177 static int add_to_lpt_heap(struct ubifs_info *c, struct ubifs_lprops *lprops,
178 int cat)
180 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
182 if (heap->cnt >= heap->max_cnt) {
183 const int b = LPT_HEAP_SZ / 2 - 1;
184 int cpos, val1, val2;
186 /* Compare to some other LEB on the bottom of heap */
187 /* Pick a position kind of randomly */
188 cpos = (((size_t)lprops >> 4) & b) + b;
189 ubifs_assert(cpos >= b);
190 ubifs_assert(cpos < LPT_HEAP_SZ);
191 ubifs_assert(cpos < heap->cnt);
193 val1 = get_heap_comp_val(lprops, cat);
194 val2 = get_heap_comp_val(heap->arr[cpos], cat);
195 if (val1 > val2) {
196 struct ubifs_lprops *lp;
198 lp = heap->arr[cpos];
199 lp->flags &= ~LPROPS_CAT_MASK;
200 lp->flags |= LPROPS_UNCAT;
201 list_add(&lp->list, &c->uncat_list);
202 lprops->hpos = cpos;
203 heap->arr[cpos] = lprops;
204 move_up_lpt_heap(c, heap, lprops, cat);
205 dbg_check_heap(c, heap, cat, lprops->hpos);
206 return 1; /* Added to heap */
208 dbg_check_heap(c, heap, cat, -1);
209 return 0; /* Not added to heap */
210 } else {
211 lprops->hpos = heap->cnt++;
212 heap->arr[lprops->hpos] = lprops;
213 move_up_lpt_heap(c, heap, lprops, cat);
214 dbg_check_heap(c, heap, cat, lprops->hpos);
215 return 1; /* Added to heap */
220 * remove_from_lpt_heap - remove LEB properties from a LEB category heap.
221 * @c: UBIFS file-system description object
222 * @lprops: LEB properties to remove
223 * @cat: LEB category
225 static void remove_from_lpt_heap(struct ubifs_info *c,
226 struct ubifs_lprops *lprops, int cat)
228 struct ubifs_lpt_heap *heap;
229 int hpos = lprops->hpos;
231 heap = &c->lpt_heap[cat - 1];
232 ubifs_assert(hpos >= 0 && hpos < heap->cnt);
233 ubifs_assert(heap->arr[hpos] == lprops);
234 heap->cnt -= 1;
235 if (hpos < heap->cnt) {
236 heap->arr[hpos] = heap->arr[heap->cnt];
237 heap->arr[hpos]->hpos = hpos;
238 adjust_lpt_heap(c, heap, heap->arr[hpos], hpos, cat);
240 dbg_check_heap(c, heap, cat, -1);
244 * lpt_heap_replace - replace lprops in a category heap.
245 * @c: UBIFS file-system description object
246 * @old_lprops: LEB properties to replace
247 * @new_lprops: LEB properties with which to replace
248 * @cat: LEB category
250 * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
251 * and the lprops that the pnode contains. When that happens, references in
252 * the category heaps to those lprops must be updated to point to the new
253 * lprops. This function does that.
255 static void lpt_heap_replace(struct ubifs_info *c,
256 struct ubifs_lprops *old_lprops,
257 struct ubifs_lprops *new_lprops, int cat)
259 struct ubifs_lpt_heap *heap;
260 int hpos = new_lprops->hpos;
262 heap = &c->lpt_heap[cat - 1];
263 heap->arr[hpos] = new_lprops;
267 * ubifs_add_to_cat - add LEB properties to a category list or heap.
268 * @c: UBIFS file-system description object
269 * @lprops: LEB properties to add
270 * @cat: LEB category to which to add
272 * LEB properties are categorized to enable fast find operations.
274 void ubifs_add_to_cat(struct ubifs_info *c, struct ubifs_lprops *lprops,
275 int cat)
277 switch (cat) {
278 case LPROPS_DIRTY:
279 case LPROPS_DIRTY_IDX:
280 case LPROPS_FREE:
281 if (add_to_lpt_heap(c, lprops, cat))
282 break;
283 /* No more room on heap so make it uncategorized */
284 cat = LPROPS_UNCAT;
285 /* Fall through */
286 case LPROPS_UNCAT:
287 list_add(&lprops->list, &c->uncat_list);
288 break;
289 case LPROPS_EMPTY:
290 list_add(&lprops->list, &c->empty_list);
291 break;
292 case LPROPS_FREEABLE:
293 list_add(&lprops->list, &c->freeable_list);
294 c->freeable_cnt += 1;
295 break;
296 case LPROPS_FRDI_IDX:
297 list_add(&lprops->list, &c->frdi_idx_list);
298 break;
299 default:
300 ubifs_assert(0);
302 lprops->flags &= ~LPROPS_CAT_MASK;
303 lprops->flags |= cat;
307 * ubifs_remove_from_cat - remove LEB properties from a category list or heap.
308 * @c: UBIFS file-system description object
309 * @lprops: LEB properties to remove
310 * @cat: LEB category from which to remove
312 * LEB properties are categorized to enable fast find operations.
314 static void ubifs_remove_from_cat(struct ubifs_info *c,
315 struct ubifs_lprops *lprops, int cat)
317 switch (cat) {
318 case LPROPS_DIRTY:
319 case LPROPS_DIRTY_IDX:
320 case LPROPS_FREE:
321 remove_from_lpt_heap(c, lprops, cat);
322 break;
323 case LPROPS_FREEABLE:
324 c->freeable_cnt -= 1;
325 ubifs_assert(c->freeable_cnt >= 0);
326 /* Fall through */
327 case LPROPS_UNCAT:
328 case LPROPS_EMPTY:
329 case LPROPS_FRDI_IDX:
330 ubifs_assert(!list_empty(&lprops->list));
331 list_del(&lprops->list);
332 break;
333 default:
334 ubifs_assert(0);
339 * ubifs_replace_cat - replace lprops in a category list or heap.
340 * @c: UBIFS file-system description object
341 * @old_lprops: LEB properties to replace
342 * @new_lprops: LEB properties with which to replace
344 * During commit it is sometimes necessary to copy a pnode (see dirty_cow_pnode)
345 * and the lprops that the pnode contains. When that happens, references in
346 * category lists and heaps must be replaced. This function does that.
348 void ubifs_replace_cat(struct ubifs_info *c, struct ubifs_lprops *old_lprops,
349 struct ubifs_lprops *new_lprops)
351 int cat;
353 cat = new_lprops->flags & LPROPS_CAT_MASK;
354 switch (cat) {
355 case LPROPS_DIRTY:
356 case LPROPS_DIRTY_IDX:
357 case LPROPS_FREE:
358 lpt_heap_replace(c, old_lprops, new_lprops, cat);
359 break;
360 case LPROPS_UNCAT:
361 case LPROPS_EMPTY:
362 case LPROPS_FREEABLE:
363 case LPROPS_FRDI_IDX:
364 list_replace(&old_lprops->list, &new_lprops->list);
365 break;
366 default:
367 ubifs_assert(0);
372 * ubifs_ensure_cat - ensure LEB properties are categorized.
373 * @c: UBIFS file-system description object
374 * @lprops: LEB properties
376 * A LEB may have fallen off of the bottom of a heap, and ended up as
377 * uncategorized even though it has enough space for us now. If that is the case
378 * this function will put the LEB back onto a heap.
380 void ubifs_ensure_cat(struct ubifs_info *c, struct ubifs_lprops *lprops)
382 int cat = lprops->flags & LPROPS_CAT_MASK;
384 if (cat != LPROPS_UNCAT)
385 return;
386 cat = ubifs_categorize_lprops(c, lprops);
387 if (cat == LPROPS_UNCAT)
388 return;
389 ubifs_remove_from_cat(c, lprops, LPROPS_UNCAT);
390 ubifs_add_to_cat(c, lprops, cat);
394 * ubifs_categorize_lprops - categorize LEB properties.
395 * @c: UBIFS file-system description object
396 * @lprops: LEB properties to categorize
398 * LEB properties are categorized to enable fast find operations. This function
399 * returns the LEB category to which the LEB properties belong. Note however
400 * that if the LEB category is stored as a heap and the heap is full, the
401 * LEB properties may have their category changed to %LPROPS_UNCAT.
403 int ubifs_categorize_lprops(const struct ubifs_info *c,
404 const struct ubifs_lprops *lprops)
406 if (lprops->flags & LPROPS_TAKEN)
407 return LPROPS_UNCAT;
409 if (lprops->free == c->leb_size) {
410 ubifs_assert(!(lprops->flags & LPROPS_INDEX));
411 return LPROPS_EMPTY;
414 if (lprops->free + lprops->dirty == c->leb_size) {
415 if (lprops->flags & LPROPS_INDEX)
416 return LPROPS_FRDI_IDX;
417 else
418 return LPROPS_FREEABLE;
421 if (lprops->flags & LPROPS_INDEX) {
422 if (lprops->dirty + lprops->free >= c->min_idx_node_sz)
423 return LPROPS_DIRTY_IDX;
424 } else {
425 if (lprops->dirty >= c->dead_wm &&
426 lprops->dirty > lprops->free)
427 return LPROPS_DIRTY;
428 if (lprops->free > 0)
429 return LPROPS_FREE;
432 return LPROPS_UNCAT;
436 * change_category - change LEB properties category.
437 * @c: UBIFS file-system description object
438 * @lprops: LEB properties to recategorize
440 * LEB properties are categorized to enable fast find operations. When the LEB
441 * properties change they must be recategorized.
443 static void change_category(struct ubifs_info *c, struct ubifs_lprops *lprops)
445 int old_cat = lprops->flags & LPROPS_CAT_MASK;
446 int new_cat = ubifs_categorize_lprops(c, lprops);
448 if (old_cat == new_cat) {
449 struct ubifs_lpt_heap *heap = &c->lpt_heap[new_cat - 1];
451 /* lprops on a heap now must be moved up or down */
452 if (new_cat < 1 || new_cat > LPROPS_HEAP_CNT)
453 return; /* Not on a heap */
454 heap = &c->lpt_heap[new_cat - 1];
455 adjust_lpt_heap(c, heap, lprops, lprops->hpos, new_cat);
456 } else {
457 ubifs_remove_from_cat(c, lprops, old_cat);
458 ubifs_add_to_cat(c, lprops, new_cat);
463 * ubifs_get_lprops - get reference to LEB properties.
464 * @c: the UBIFS file-system description object
466 * This function locks lprops. Lprops have to be unlocked by
467 * 'ubifs_release_lprops()'.
469 void ubifs_get_lprops(struct ubifs_info *c)
471 mutex_lock(&c->lp_mutex);
475 * calc_dark - calculate LEB dark space size.
476 * @c: the UBIFS file-system description object
477 * @spc: amount of free and dirty space in the LEB
479 * This function calculates amount of dark space in an LEB which has @spc bytes
480 * of free and dirty space. Returns the calculations result.
482 * Dark space is the space which is not always usable - it depends on which
483 * nodes are written in which order. E.g., if an LEB has only 512 free bytes,
484 * it is dark space, because it cannot fit a large data node. So UBIFS cannot
485 * count on this LEB and treat these 512 bytes as usable because it is not true
486 * if, for example, only big chunks of uncompressible data will be written to
487 * the FS.
489 static int calc_dark(struct ubifs_info *c, int spc)
491 ubifs_assert(!(spc & 7));
493 if (spc < c->dark_wm)
494 return spc;
497 * If we have slightly more space then the dark space watermark, we can
498 * anyway safely assume it we'll be able to write a node of the
499 * smallest size there.
501 if (spc - c->dark_wm < MIN_WRITE_SZ)
502 return spc - MIN_WRITE_SZ;
504 return c->dark_wm;
508 * is_lprops_dirty - determine if LEB properties are dirty.
509 * @c: the UBIFS file-system description object
510 * @lprops: LEB properties to test
512 static int is_lprops_dirty(struct ubifs_info *c, struct ubifs_lprops *lprops)
514 struct ubifs_pnode *pnode;
515 int pos;
517 pos = (lprops->lnum - c->main_first) & (UBIFS_LPT_FANOUT - 1);
518 pnode = (struct ubifs_pnode *)container_of(lprops - pos,
519 struct ubifs_pnode,
520 lprops[0]);
521 return !test_bit(COW_ZNODE, &pnode->flags) &&
522 test_bit(DIRTY_CNODE, &pnode->flags);
526 * ubifs_change_lp - change LEB properties.
527 * @c: the UBIFS file-system description object
528 * @lp: LEB properties to change
529 * @free: new free space amount
530 * @dirty: new dirty space amount
531 * @flags: new flags
532 * @idx_gc_cnt: change to the count of idx_gc list
534 * This function changes LEB properties. This function does not change a LEB
535 * property (@free, @dirty or @flag) if the value passed is %LPROPS_NC.
537 * This function returns a pointer to the updated LEB properties on success
538 * and a negative error code on failure. N.B. the LEB properties may have had to
539 * be copied (due to COW) and consequently the pointer returned may not be the
540 * same as the pointer passed.
542 const struct ubifs_lprops *ubifs_change_lp(struct ubifs_info *c,
543 const struct ubifs_lprops *lp,
544 int free, int dirty, int flags,
545 int idx_gc_cnt)
548 * This is the only function that is allowed to change lprops, so we
549 * discard the const qualifier.
551 struct ubifs_lprops *lprops = (struct ubifs_lprops *)lp;
553 dbg_lp("LEB %d, free %d, dirty %d, flags %d",
554 lprops->lnum, free, dirty, flags);
556 ubifs_assert(mutex_is_locked(&c->lp_mutex));
557 ubifs_assert(c->lst.empty_lebs >= 0 &&
558 c->lst.empty_lebs <= c->main_lebs);
559 ubifs_assert(c->freeable_cnt >= 0);
560 ubifs_assert(c->freeable_cnt <= c->main_lebs);
561 ubifs_assert(c->lst.taken_empty_lebs >= 0);
562 ubifs_assert(c->lst.taken_empty_lebs <= c->lst.empty_lebs);
563 ubifs_assert(!(c->lst.total_free & 7) && !(c->lst.total_dirty & 7));
564 ubifs_assert(!(c->lst.total_dead & 7) && !(c->lst.total_dark & 7));
565 ubifs_assert(!(c->lst.total_used & 7));
566 ubifs_assert(free == LPROPS_NC || free >= 0);
567 ubifs_assert(dirty == LPROPS_NC || dirty >= 0);
569 if (!is_lprops_dirty(c, lprops)) {
570 lprops = ubifs_lpt_lookup_dirty(c, lprops->lnum);
571 if (IS_ERR(lprops))
572 return lprops;
573 } else
574 ubifs_assert(lprops == ubifs_lpt_lookup_dirty(c, lprops->lnum));
576 ubifs_assert(!(lprops->free & 7) && !(lprops->dirty & 7));
578 spin_lock(&c->space_lock);
580 if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
581 c->lst.taken_empty_lebs -= 1;
583 if (!(lprops->flags & LPROPS_INDEX)) {
584 int old_spc;
586 old_spc = lprops->free + lprops->dirty;
587 if (old_spc < c->dead_wm)
588 c->lst.total_dead -= old_spc;
589 else
590 c->lst.total_dark -= calc_dark(c, old_spc);
592 c->lst.total_used -= c->leb_size - old_spc;
595 if (free != LPROPS_NC) {
596 free = ALIGN(free, 8);
597 c->lst.total_free += free - lprops->free;
599 /* Increase or decrease empty LEBs counter if needed */
600 if (free == c->leb_size) {
601 if (lprops->free != c->leb_size)
602 c->lst.empty_lebs += 1;
603 } else if (lprops->free == c->leb_size)
604 c->lst.empty_lebs -= 1;
605 lprops->free = free;
608 if (dirty != LPROPS_NC) {
609 dirty = ALIGN(dirty, 8);
610 c->lst.total_dirty += dirty - lprops->dirty;
611 lprops->dirty = dirty;
614 if (flags != LPROPS_NC) {
615 /* Take care about indexing LEBs counter if needed */
616 if ((lprops->flags & LPROPS_INDEX)) {
617 if (!(flags & LPROPS_INDEX))
618 c->lst.idx_lebs -= 1;
619 } else if (flags & LPROPS_INDEX)
620 c->lst.idx_lebs += 1;
621 lprops->flags = flags;
624 if (!(lprops->flags & LPROPS_INDEX)) {
625 int new_spc;
627 new_spc = lprops->free + lprops->dirty;
628 if (new_spc < c->dead_wm)
629 c->lst.total_dead += new_spc;
630 else
631 c->lst.total_dark += calc_dark(c, new_spc);
633 c->lst.total_used += c->leb_size - new_spc;
636 if ((lprops->flags & LPROPS_TAKEN) && lprops->free == c->leb_size)
637 c->lst.taken_empty_lebs += 1;
639 change_category(c, lprops);
641 c->idx_gc_cnt += idx_gc_cnt;
643 spin_unlock(&c->space_lock);
645 return lprops;
649 * ubifs_release_lprops - release lprops lock.
650 * @c: the UBIFS file-system description object
652 * This function has to be called after each 'ubifs_get_lprops()' call to
653 * unlock lprops.
655 void ubifs_release_lprops(struct ubifs_info *c)
657 ubifs_assert(mutex_is_locked(&c->lp_mutex));
658 ubifs_assert(c->lst.empty_lebs >= 0 &&
659 c->lst.empty_lebs <= c->main_lebs);
661 mutex_unlock(&c->lp_mutex);
665 * ubifs_get_lp_stats - get lprops statistics.
666 * @c: UBIFS file-system description object
667 * @st: return statistics
669 void ubifs_get_lp_stats(struct ubifs_info *c, struct ubifs_lp_stats *st)
671 spin_lock(&c->space_lock);
672 memcpy(st, &c->lst, sizeof(struct ubifs_lp_stats));
673 spin_unlock(&c->space_lock);
677 * ubifs_change_one_lp - change 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
682 * @flags_set: flags to set
683 * @flags_clean: flags to clean
684 * @idx_gc_cnt: change to the count of idx_gc list
686 * This function changes properties of LEB @lnum. It is a helper wrapper over
687 * 'ubifs_change_lp()' which hides lprops get/release. The arguments are the
688 * same as in case of 'ubifs_change_lp()'. Returns zero in case of success and
689 * a negative error code in case of failure.
691 int ubifs_change_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
692 int flags_set, int flags_clean, int idx_gc_cnt)
694 int err = 0, flags;
695 const struct ubifs_lprops *lp;
697 ubifs_get_lprops(c);
699 lp = ubifs_lpt_lookup_dirty(c, lnum);
700 if (IS_ERR(lp)) {
701 err = PTR_ERR(lp);
702 goto out;
705 flags = (lp->flags | flags_set) & ~flags_clean;
706 lp = ubifs_change_lp(c, lp, free, dirty, flags, idx_gc_cnt);
707 if (IS_ERR(lp))
708 err = PTR_ERR(lp);
710 out:
711 ubifs_release_lprops(c);
712 return err;
716 * ubifs_update_one_lp - update LEB properties.
717 * @c: the UBIFS file-system description object
718 * @lnum: LEB to change properties for
719 * @free: amount of free space
720 * @dirty: amount of dirty space to add
721 * @flags_set: flags to set
722 * @flags_clean: flags to clean
724 * This function is the same as 'ubifs_change_one_lp()' but @dirty is added to
725 * current dirty space, not substitutes it.
727 int ubifs_update_one_lp(struct ubifs_info *c, int lnum, int free, int dirty,
728 int flags_set, int flags_clean)
730 int err = 0, flags;
731 const struct ubifs_lprops *lp;
733 ubifs_get_lprops(c);
735 lp = ubifs_lpt_lookup_dirty(c, lnum);
736 if (IS_ERR(lp)) {
737 err = PTR_ERR(lp);
738 goto out;
741 flags = (lp->flags | flags_set) & ~flags_clean;
742 lp = ubifs_change_lp(c, lp, free, lp->dirty + dirty, flags, 0);
743 if (IS_ERR(lp))
744 err = PTR_ERR(lp);
746 out:
747 ubifs_release_lprops(c);
748 return err;
752 * ubifs_read_one_lp - read LEB properties.
753 * @c: the UBIFS file-system description object
754 * @lnum: LEB to read properties for
755 * @lp: where to store read properties
757 * This helper function reads properties of a LEB @lnum and stores them in @lp.
758 * Returns zero in case of success and a negative error code in case of
759 * failure.
761 int ubifs_read_one_lp(struct ubifs_info *c, int lnum, struct ubifs_lprops *lp)
763 int err = 0;
764 const struct ubifs_lprops *lpp;
766 ubifs_get_lprops(c);
768 lpp = ubifs_lpt_lookup(c, lnum);
769 if (IS_ERR(lpp)) {
770 err = PTR_ERR(lpp);
771 goto out;
774 memcpy(lp, lpp, sizeof(struct ubifs_lprops));
776 out:
777 ubifs_release_lprops(c);
778 return err;
782 * ubifs_fast_find_free - try to find a LEB with free space quickly.
783 * @c: the UBIFS file-system description object
785 * This function returns LEB properties for a LEB with free space or %NULL if
786 * the function is unable to find a LEB quickly.
788 const struct ubifs_lprops *ubifs_fast_find_free(struct ubifs_info *c)
790 struct ubifs_lprops *lprops;
791 struct ubifs_lpt_heap *heap;
793 ubifs_assert(mutex_is_locked(&c->lp_mutex));
795 heap = &c->lpt_heap[LPROPS_FREE - 1];
796 if (heap->cnt == 0)
797 return NULL;
799 lprops = heap->arr[0];
800 ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
801 ubifs_assert(!(lprops->flags & LPROPS_INDEX));
802 return lprops;
806 * ubifs_fast_find_empty - try to find an empty LEB quickly.
807 * @c: the UBIFS file-system description object
809 * This function returns LEB properties for an empty LEB or %NULL if the
810 * function is unable to find an empty LEB quickly.
812 const struct ubifs_lprops *ubifs_fast_find_empty(struct ubifs_info *c)
814 struct ubifs_lprops *lprops;
816 ubifs_assert(mutex_is_locked(&c->lp_mutex));
818 if (list_empty(&c->empty_list))
819 return NULL;
821 lprops = list_entry(c->empty_list.next, struct ubifs_lprops, list);
822 ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
823 ubifs_assert(!(lprops->flags & LPROPS_INDEX));
824 ubifs_assert(lprops->free == c->leb_size);
825 return lprops;
829 * ubifs_fast_find_freeable - try to find a freeable LEB quickly.
830 * @c: the UBIFS file-system description object
832 * This function returns LEB properties for a freeable LEB or %NULL if the
833 * function is unable to find a freeable LEB quickly.
835 const struct ubifs_lprops *ubifs_fast_find_freeable(struct ubifs_info *c)
837 struct ubifs_lprops *lprops;
839 ubifs_assert(mutex_is_locked(&c->lp_mutex));
841 if (list_empty(&c->freeable_list))
842 return NULL;
844 lprops = list_entry(c->freeable_list.next, struct ubifs_lprops, list);
845 ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
846 ubifs_assert(!(lprops->flags & LPROPS_INDEX));
847 ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
848 ubifs_assert(c->freeable_cnt > 0);
849 return lprops;
853 * ubifs_fast_find_frdi_idx - try to find a freeable index LEB quickly.
854 * @c: the UBIFS file-system description object
856 * This function returns LEB properties for a freeable index LEB or %NULL if the
857 * function is unable to find a freeable index LEB quickly.
859 const struct ubifs_lprops *ubifs_fast_find_frdi_idx(struct ubifs_info *c)
861 struct ubifs_lprops *lprops;
863 ubifs_assert(mutex_is_locked(&c->lp_mutex));
865 if (list_empty(&c->frdi_idx_list))
866 return NULL;
868 lprops = list_entry(c->frdi_idx_list.next, struct ubifs_lprops, list);
869 ubifs_assert(!(lprops->flags & LPROPS_TAKEN));
870 ubifs_assert((lprops->flags & LPROPS_INDEX));
871 ubifs_assert(lprops->free + lprops->dirty == c->leb_size);
872 return lprops;
875 #ifdef CONFIG_UBIFS_FS_DEBUG
878 * dbg_check_cats - check category heaps and lists.
879 * @c: UBIFS file-system description object
881 * This function returns %0 on success and a negative error code on failure.
883 int dbg_check_cats(struct ubifs_info *c)
885 struct ubifs_lprops *lprops;
886 struct list_head *pos;
887 int i, cat;
889 if (!(ubifs_chk_flags & (UBIFS_CHK_GEN | UBIFS_CHK_LPROPS)))
890 return 0;
892 list_for_each_entry(lprops, &c->empty_list, list) {
893 if (lprops->free != c->leb_size) {
894 ubifs_err("non-empty LEB %d on empty list "
895 "(free %d dirty %d flags %d)", lprops->lnum,
896 lprops->free, lprops->dirty, lprops->flags);
897 return -EINVAL;
899 if (lprops->flags & LPROPS_TAKEN) {
900 ubifs_err("taken LEB %d on empty list "
901 "(free %d dirty %d flags %d)", lprops->lnum,
902 lprops->free, lprops->dirty, lprops->flags);
903 return -EINVAL;
907 i = 0;
908 list_for_each_entry(lprops, &c->freeable_list, list) {
909 if (lprops->free + lprops->dirty != c->leb_size) {
910 ubifs_err("non-freeable LEB %d on freeable list "
911 "(free %d dirty %d flags %d)", lprops->lnum,
912 lprops->free, lprops->dirty, lprops->flags);
913 return -EINVAL;
915 if (lprops->flags & LPROPS_TAKEN) {
916 ubifs_err("taken LEB %d on freeable list "
917 "(free %d dirty %d flags %d)", lprops->lnum,
918 lprops->free, lprops->dirty, lprops->flags);
919 return -EINVAL;
921 i += 1;
923 if (i != c->freeable_cnt) {
924 ubifs_err("freeable list count %d expected %d", i,
925 c->freeable_cnt);
926 return -EINVAL;
929 i = 0;
930 list_for_each(pos, &c->idx_gc)
931 i += 1;
932 if (i != c->idx_gc_cnt) {
933 ubifs_err("idx_gc list count %d expected %d", i,
934 c->idx_gc_cnt);
935 return -EINVAL;
938 list_for_each_entry(lprops, &c->frdi_idx_list, list) {
939 if (lprops->free + lprops->dirty != c->leb_size) {
940 ubifs_err("non-freeable LEB %d on frdi_idx list "
941 "(free %d dirty %d flags %d)", lprops->lnum,
942 lprops->free, lprops->dirty, lprops->flags);
943 return -EINVAL;
945 if (lprops->flags & LPROPS_TAKEN) {
946 ubifs_err("taken LEB %d on frdi_idx list "
947 "(free %d dirty %d flags %d)", lprops->lnum,
948 lprops->free, lprops->dirty, lprops->flags);
949 return -EINVAL;
951 if (!(lprops->flags & LPROPS_INDEX)) {
952 ubifs_err("non-index LEB %d on frdi_idx list "
953 "(free %d dirty %d flags %d)", lprops->lnum,
954 lprops->free, lprops->dirty, lprops->flags);
955 return -EINVAL;
959 for (cat = 1; cat <= LPROPS_HEAP_CNT; cat++) {
960 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
962 for (i = 0; i < heap->cnt; i++) {
963 lprops = heap->arr[i];
964 if (!lprops) {
965 ubifs_err("null ptr in LPT heap cat %d", cat);
966 return -EINVAL;
968 if (lprops->hpos != i) {
969 ubifs_err("bad ptr in LPT heap cat %d", cat);
970 return -EINVAL;
972 if (lprops->flags & LPROPS_TAKEN) {
973 ubifs_err("taken LEB in LPT heap cat %d", cat);
974 return -EINVAL;
979 return 0;
982 void dbg_check_heap(struct ubifs_info *c, struct ubifs_lpt_heap *heap, int cat,
983 int add_pos)
985 int i = 0, j, err = 0;
987 if (!(ubifs_chk_flags & (UBIFS_CHK_GEN | UBIFS_CHK_LPROPS)))
988 return;
990 for (i = 0; i < heap->cnt; i++) {
991 struct ubifs_lprops *lprops = heap->arr[i];
992 struct ubifs_lprops *lp;
994 if (i != add_pos)
995 if ((lprops->flags & LPROPS_CAT_MASK) != cat) {
996 err = 1;
997 goto out;
999 if (lprops->hpos != i) {
1000 err = 2;
1001 goto out;
1003 lp = ubifs_lpt_lookup(c, lprops->lnum);
1004 if (IS_ERR(lp)) {
1005 err = 3;
1006 goto out;
1008 if (lprops != lp) {
1009 dbg_msg("lprops %zx lp %zx lprops->lnum %d lp->lnum %d",
1010 (size_t)lprops, (size_t)lp, lprops->lnum,
1011 lp->lnum);
1012 err = 4;
1013 goto out;
1015 for (j = 0; j < i; j++) {
1016 lp = heap->arr[j];
1017 if (lp == lprops) {
1018 err = 5;
1019 goto out;
1021 if (lp->lnum == lprops->lnum) {
1022 err = 6;
1023 goto out;
1027 out:
1028 if (err) {
1029 dbg_msg("failed cat %d hpos %d err %d", cat, i, err);
1030 dbg_dump_stack();
1031 dbg_dump_heap(c, heap, cat);
1036 * struct scan_check_data - data provided to scan callback function.
1037 * @lst: LEB properties statistics
1038 * @err: error code
1040 struct scan_check_data {
1041 struct ubifs_lp_stats lst;
1042 int err;
1046 * scan_check_cb - scan callback.
1047 * @c: the UBIFS file-system description object
1048 * @lp: LEB properties to scan
1049 * @in_tree: whether the LEB properties are in main memory
1050 * @data: information passed to and from the caller of the scan
1052 * This function returns a code that indicates whether the scan should continue
1053 * (%LPT_SCAN_CONTINUE), whether the LEB properties should be added to the tree
1054 * in main memory (%LPT_SCAN_ADD), or whether the scan should stop
1055 * (%LPT_SCAN_STOP).
1057 static int scan_check_cb(struct ubifs_info *c,
1058 const struct ubifs_lprops *lp, int in_tree,
1059 struct scan_check_data *data)
1061 struct ubifs_scan_leb *sleb;
1062 struct ubifs_scan_node *snod;
1063 struct ubifs_lp_stats *lst = &data->lst;
1064 int cat, lnum = lp->lnum, is_idx = 0, used = 0, free, dirty;
1066 cat = lp->flags & LPROPS_CAT_MASK;
1067 if (cat != LPROPS_UNCAT) {
1068 cat = ubifs_categorize_lprops(c, lp);
1069 if (cat != (lp->flags & LPROPS_CAT_MASK)) {
1070 ubifs_err("bad LEB category %d expected %d",
1071 (lp->flags & LPROPS_CAT_MASK), cat);
1072 goto out;
1076 /* Check lp is on its category list (if it has one) */
1077 if (in_tree) {
1078 struct list_head *list = NULL;
1080 switch (cat) {
1081 case LPROPS_EMPTY:
1082 list = &c->empty_list;
1083 break;
1084 case LPROPS_FREEABLE:
1085 list = &c->freeable_list;
1086 break;
1087 case LPROPS_FRDI_IDX:
1088 list = &c->frdi_idx_list;
1089 break;
1090 case LPROPS_UNCAT:
1091 list = &c->uncat_list;
1092 break;
1094 if (list) {
1095 struct ubifs_lprops *lprops;
1096 int found = 0;
1098 list_for_each_entry(lprops, list, list) {
1099 if (lprops == lp) {
1100 found = 1;
1101 break;
1104 if (!found) {
1105 ubifs_err("bad LPT list (category %d)", cat);
1106 goto out;
1111 /* Check lp is on its category heap (if it has one) */
1112 if (in_tree && cat > 0 && cat <= LPROPS_HEAP_CNT) {
1113 struct ubifs_lpt_heap *heap = &c->lpt_heap[cat - 1];
1115 if ((lp->hpos != -1 && heap->arr[lp->hpos]->lnum != lnum) ||
1116 lp != heap->arr[lp->hpos]) {
1117 ubifs_err("bad LPT heap (category %d)", cat);
1118 goto out;
1122 sleb = ubifs_scan(c, lnum, 0, c->dbg_buf);
1123 if (IS_ERR(sleb)) {
1125 * After an unclean unmount, empty and freeable LEBs
1126 * may contain garbage.
1128 if (lp->free == c->leb_size) {
1129 ubifs_err("scan errors were in empty LEB "
1130 "- continuing checking");
1131 lst->empty_lebs += 1;
1132 lst->total_free += c->leb_size;
1133 lst->total_dark += calc_dark(c, c->leb_size);
1134 return LPT_SCAN_CONTINUE;
1137 if (lp->free + lp->dirty == c->leb_size &&
1138 !(lp->flags & LPROPS_INDEX)) {
1139 ubifs_err("scan errors were in freeable LEB "
1140 "- continuing checking");
1141 lst->total_free += lp->free;
1142 lst->total_dirty += lp->dirty;
1143 lst->total_dark += calc_dark(c, c->leb_size);
1144 return LPT_SCAN_CONTINUE;
1146 data->err = PTR_ERR(sleb);
1147 return LPT_SCAN_STOP;
1150 is_idx = -1;
1151 list_for_each_entry(snod, &sleb->nodes, list) {
1152 int found, level = 0;
1154 cond_resched();
1156 if (is_idx == -1)
1157 is_idx = (snod->type == UBIFS_IDX_NODE) ? 1 : 0;
1159 if (is_idx && snod->type != UBIFS_IDX_NODE) {
1160 ubifs_err("indexing node in data LEB %d:%d",
1161 lnum, snod->offs);
1162 goto out_destroy;
1165 if (snod->type == UBIFS_IDX_NODE) {
1166 struct ubifs_idx_node *idx = snod->node;
1168 key_read(c, ubifs_idx_key(c, idx), &snod->key);
1169 level = le16_to_cpu(idx->level);
1172 found = ubifs_tnc_has_node(c, &snod->key, level, lnum,
1173 snod->offs, is_idx);
1174 if (found) {
1175 if (found < 0)
1176 goto out_destroy;
1177 used += ALIGN(snod->len, 8);
1181 free = c->leb_size - sleb->endpt;
1182 dirty = sleb->endpt - used;
1184 if (free > c->leb_size || free < 0 || dirty > c->leb_size ||
1185 dirty < 0) {
1186 ubifs_err("bad calculated accounting for LEB %d: "
1187 "free %d, dirty %d", lnum, free, dirty);
1188 goto out_destroy;
1191 if (lp->free + lp->dirty == c->leb_size &&
1192 free + dirty == c->leb_size)
1193 if ((is_idx && !(lp->flags & LPROPS_INDEX)) ||
1194 (!is_idx && free == c->leb_size) ||
1195 lp->free == c->leb_size) {
1197 * Empty or freeable LEBs could contain index
1198 * nodes from an uncompleted commit due to an
1199 * unclean unmount. Or they could be empty for
1200 * the same reason. Or it may simply not have been
1201 * unmapped.
1203 free = lp->free;
1204 dirty = lp->dirty;
1205 is_idx = 0;
1208 if (is_idx && lp->free + lp->dirty == free + dirty &&
1209 lnum != c->ihead_lnum) {
1211 * After an unclean unmount, an index LEB could have a different
1212 * amount of free space than the value recorded by lprops. That
1213 * is because the in-the-gaps method may use free space or
1214 * create free space (as a side-effect of using ubi_leb_change
1215 * and not writing the whole LEB). The incorrect free space
1216 * value is not a problem because the index is only ever
1217 * allocated empty LEBs, so there will never be an attempt to
1218 * write to the free space at the end of an index LEB - except
1219 * by the in-the-gaps method for which it is not a problem.
1221 free = lp->free;
1222 dirty = lp->dirty;
1225 if (lp->free != free || lp->dirty != dirty)
1226 goto out_print;
1228 if (is_idx && !(lp->flags & LPROPS_INDEX)) {
1229 if (free == c->leb_size)
1230 /* Free but not unmapped LEB, it's fine */
1231 is_idx = 0;
1232 else {
1233 ubifs_err("indexing node without indexing "
1234 "flag");
1235 goto out_print;
1239 if (!is_idx && (lp->flags & LPROPS_INDEX)) {
1240 ubifs_err("data node with indexing flag");
1241 goto out_print;
1244 if (free == c->leb_size)
1245 lst->empty_lebs += 1;
1247 if (is_idx)
1248 lst->idx_lebs += 1;
1250 if (!(lp->flags & LPROPS_INDEX))
1251 lst->total_used += c->leb_size - free - dirty;
1252 lst->total_free += free;
1253 lst->total_dirty += dirty;
1255 if (!(lp->flags & LPROPS_INDEX)) {
1256 int spc = free + dirty;
1258 if (spc < c->dead_wm)
1259 lst->total_dead += spc;
1260 else
1261 lst->total_dark += calc_dark(c, spc);
1264 ubifs_scan_destroy(sleb);
1266 return LPT_SCAN_CONTINUE;
1268 out_print:
1269 ubifs_err("bad accounting of LEB %d: free %d, dirty %d flags %#x, "
1270 "should be free %d, dirty %d",
1271 lnum, lp->free, lp->dirty, lp->flags, free, dirty);
1272 dbg_dump_leb(c, lnum);
1273 out_destroy:
1274 ubifs_scan_destroy(sleb);
1275 out:
1276 data->err = -EINVAL;
1277 return LPT_SCAN_STOP;
1281 * dbg_check_lprops - check all LEB properties.
1282 * @c: UBIFS file-system description object
1284 * This function checks all LEB properties and makes sure they are all correct.
1285 * It returns zero if everything is fine, %-EINVAL if there is an inconsistency
1286 * and other negative error codes in case of other errors. This function is
1287 * called while the file system is locked (because of commit start), so no
1288 * additional locking is required. Note that locking the LPT mutex would cause
1289 * a circular lock dependency with the TNC mutex.
1291 int dbg_check_lprops(struct ubifs_info *c)
1293 int i, err;
1294 struct scan_check_data data;
1295 struct ubifs_lp_stats *lst = &data.lst;
1297 if (!(ubifs_chk_flags & UBIFS_CHK_LPROPS))
1298 return 0;
1301 * As we are going to scan the media, the write buffers have to be
1302 * synchronized.
1304 for (i = 0; i < c->jhead_cnt; i++) {
1305 err = ubifs_wbuf_sync(&c->jheads[i].wbuf);
1306 if (err)
1307 return err;
1310 memset(lst, 0, sizeof(struct ubifs_lp_stats));
1312 data.err = 0;
1313 err = ubifs_lpt_scan_nolock(c, c->main_first, c->leb_cnt - 1,
1314 (ubifs_lpt_scan_callback)scan_check_cb,
1315 &data);
1316 if (err && err != -ENOSPC)
1317 goto out;
1318 if (data.err) {
1319 err = data.err;
1320 goto out;
1323 if (lst->empty_lebs != c->lst.empty_lebs ||
1324 lst->idx_lebs != c->lst.idx_lebs ||
1325 lst->total_free != c->lst.total_free ||
1326 lst->total_dirty != c->lst.total_dirty ||
1327 lst->total_used != c->lst.total_used) {
1328 ubifs_err("bad overall accounting");
1329 ubifs_err("calculated: empty_lebs %d, idx_lebs %d, "
1330 "total_free %lld, total_dirty %lld, total_used %lld",
1331 lst->empty_lebs, lst->idx_lebs, lst->total_free,
1332 lst->total_dirty, lst->total_used);
1333 ubifs_err("read from lprops: empty_lebs %d, idx_lebs %d, "
1334 "total_free %lld, total_dirty %lld, total_used %lld",
1335 c->lst.empty_lebs, c->lst.idx_lebs, c->lst.total_free,
1336 c->lst.total_dirty, c->lst.total_used);
1337 err = -EINVAL;
1338 goto out;
1341 if (lst->total_dead != c->lst.total_dead ||
1342 lst->total_dark != c->lst.total_dark) {
1343 ubifs_err("bad dead/dark space accounting");
1344 ubifs_err("calculated: total_dead %lld, total_dark %lld",
1345 lst->total_dead, lst->total_dark);
1346 ubifs_err("read from lprops: total_dead %lld, total_dark %lld",
1347 c->lst.total_dead, c->lst.total_dark);
1348 err = -EINVAL;
1349 goto out;
1352 err = dbg_check_cats(c);
1353 out:
1354 return err;
1357 #endif /* CONFIG_UBIFS_FS_DEBUG */