1 /*
2  * Copyright (C) 2011 Red Hat, Inc.
3  *
4  * This file is released under the GPL.
5  */
6 
7 #include "dm-space-map-common.h"
8 #include "dm-transaction-manager.h"
9 
10 #include <linux/bitops.h>
11 #include <linux/device-mapper.h>
12 
13 #define DM_MSG_PREFIX "space map common"
14 
15 /*----------------------------------------------------------------*/
16 
17 /*
18  * Index validator.
19  */
20 #define INDEX_CSUM_XOR 160478
21 
22 static void index_prepare_for_write(struct dm_block_validator *v,
23 				    struct dm_block *b,
24 				    size_t block_size)
25 {
26 	struct disk_metadata_index *mi_le = dm_block_data(b);
27 
28 	mi_le->blocknr = cpu_to_le64(dm_block_location(b));
29 	mi_le->csum = cpu_to_le32(dm_bm_checksum(&mi_le->padding,
30 						 block_size - sizeof(__le32),
31 						 INDEX_CSUM_XOR));
32 }
33 
34 static int index_check(struct dm_block_validator *v,
35 		       struct dm_block *b,
36 		       size_t block_size)
37 {
38 	struct disk_metadata_index *mi_le = dm_block_data(b);
39 	__le32 csum_disk;
40 
41 	if (dm_block_location(b) != le64_to_cpu(mi_le->blocknr)) {
42 		DMERR_LIMIT("index_check failed: blocknr %llu != wanted %llu",
43 			    le64_to_cpu(mi_le->blocknr), dm_block_location(b));
44 		return -ENOTBLK;
45 	}
46 
47 	csum_disk = cpu_to_le32(dm_bm_checksum(&mi_le->padding,
48 					       block_size - sizeof(__le32),
49 					       INDEX_CSUM_XOR));
50 	if (csum_disk != mi_le->csum) {
51 		DMERR_LIMIT("index_check failed: csum %u != wanted %u",
52 			    le32_to_cpu(csum_disk), le32_to_cpu(mi_le->csum));
53 		return -EILSEQ;
54 	}
55 
56 	return 0;
57 }
58 
59 static struct dm_block_validator index_validator = {
60 	.name = "index",
61 	.prepare_for_write = index_prepare_for_write,
62 	.check = index_check
63 };
64 
65 /*----------------------------------------------------------------*/
66 
67 /*
68  * Bitmap validator
69  */
70 #define BITMAP_CSUM_XOR 240779
71 
72 static void dm_bitmap_prepare_for_write(struct dm_block_validator *v,
73 					struct dm_block *b,
74 					size_t block_size)
75 {
76 	struct disk_bitmap_header *disk_header = dm_block_data(b);
77 
78 	disk_header->blocknr = cpu_to_le64(dm_block_location(b));
79 	disk_header->csum = cpu_to_le32(dm_bm_checksum(&disk_header->not_used,
80 						       block_size - sizeof(__le32),
81 						       BITMAP_CSUM_XOR));
82 }
83 
84 static int dm_bitmap_check(struct dm_block_validator *v,
85 			   struct dm_block *b,
86 			   size_t block_size)
87 {
88 	struct disk_bitmap_header *disk_header = dm_block_data(b);
89 	__le32 csum_disk;
90 
91 	if (dm_block_location(b) != le64_to_cpu(disk_header->blocknr)) {
92 		DMERR_LIMIT("bitmap check failed: blocknr %llu != wanted %llu",
93 			    le64_to_cpu(disk_header->blocknr), dm_block_location(b));
94 		return -ENOTBLK;
95 	}
96 
97 	csum_disk = cpu_to_le32(dm_bm_checksum(&disk_header->not_used,
98 					       block_size - sizeof(__le32),
99 					       BITMAP_CSUM_XOR));
100 	if (csum_disk != disk_header->csum) {
101 		DMERR_LIMIT("bitmap check failed: csum %u != wanted %u",
102 			    le32_to_cpu(csum_disk), le32_to_cpu(disk_header->csum));
103 		return -EILSEQ;
104 	}
105 
106 	return 0;
107 }
108 
109 static struct dm_block_validator dm_sm_bitmap_validator = {
110 	.name = "sm_bitmap",
111 	.prepare_for_write = dm_bitmap_prepare_for_write,
112 	.check = dm_bitmap_check,
113 };
114 
115 /*----------------------------------------------------------------*/
116 
117 #define ENTRIES_PER_WORD 32
118 #define ENTRIES_SHIFT	5
119 
120 static void *dm_bitmap_data(struct dm_block *b)
121 {
122 	return dm_block_data(b) + sizeof(struct disk_bitmap_header);
123 }
124 
125 #define WORD_MASK_HIGH 0xAAAAAAAAAAAAAAAAULL
126 
127 static unsigned dm_bitmap_word_used(void *addr, unsigned b)
128 {
129 	__le64 *words_le = addr;
130 	__le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
131 
132 	uint64_t bits = le64_to_cpu(*w_le);
133 	uint64_t mask = (bits + WORD_MASK_HIGH + 1) & WORD_MASK_HIGH;
134 
135 	return !(~bits & mask);
136 }
137 
138 static unsigned sm_lookup_bitmap(void *addr, unsigned b)
139 {
140 	__le64 *words_le = addr;
141 	__le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
142 	unsigned hi, lo;
143 
144 	b = (b & (ENTRIES_PER_WORD - 1)) << 1;
145 	hi = !!test_bit_le(b, (void *) w_le);
146 	lo = !!test_bit_le(b + 1, (void *) w_le);
147 	return (hi << 1) | lo;
148 }
149 
150 static void sm_set_bitmap(void *addr, unsigned b, unsigned val)
151 {
152 	__le64 *words_le = addr;
153 	__le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
154 
155 	b = (b & (ENTRIES_PER_WORD - 1)) << 1;
156 
157 	if (val & 2)
158 		__set_bit_le(b, (void *) w_le);
159 	else
160 		__clear_bit_le(b, (void *) w_le);
161 
162 	if (val & 1)
163 		__set_bit_le(b + 1, (void *) w_le);
164 	else
165 		__clear_bit_le(b + 1, (void *) w_le);
166 }
167 
168 static int sm_find_free(void *addr, unsigned begin, unsigned end,
169 			unsigned *result)
170 {
171 	while (begin < end) {
172 		if (!(begin & (ENTRIES_PER_WORD - 1)) &&
173 		    dm_bitmap_word_used(addr, begin)) {
174 			begin += ENTRIES_PER_WORD;
175 			continue;
176 		}
177 
178 		if (!sm_lookup_bitmap(addr, begin)) {
179 			*result = begin;
180 			return 0;
181 		}
182 
183 		begin++;
184 	}
185 
186 	return -ENOSPC;
187 }
188 
189 /*----------------------------------------------------------------*/
190 
191 static int sm_ll_init(struct ll_disk *ll, struct dm_transaction_manager *tm)
192 {
193 	memset(ll, 0, sizeof(struct ll_disk));
194 
195 	ll->tm = tm;
196 
197 	ll->bitmap_info.tm = tm;
198 	ll->bitmap_info.levels = 1;
199 
200 	/*
201 	 * Because the new bitmap blocks are created via a shadow
202 	 * operation, the old entry has already had its reference count
203 	 * decremented and we don't need the btree to do any bookkeeping.
204 	 */
205 	ll->bitmap_info.value_type.size = sizeof(struct disk_index_entry);
206 	ll->bitmap_info.value_type.inc = NULL;
207 	ll->bitmap_info.value_type.dec = NULL;
208 	ll->bitmap_info.value_type.equal = NULL;
209 
210 	ll->ref_count_info.tm = tm;
211 	ll->ref_count_info.levels = 1;
212 	ll->ref_count_info.value_type.size = sizeof(uint32_t);
213 	ll->ref_count_info.value_type.inc = NULL;
214 	ll->ref_count_info.value_type.dec = NULL;
215 	ll->ref_count_info.value_type.equal = NULL;
216 
217 	ll->block_size = dm_bm_block_size(dm_tm_get_bm(tm));
218 
219 	if (ll->block_size > (1 << 30)) {
220 		DMERR("block size too big to hold bitmaps");
221 		return -EINVAL;
222 	}
223 
224 	ll->entries_per_block = (ll->block_size - sizeof(struct disk_bitmap_header)) *
225 		ENTRIES_PER_BYTE;
226 	ll->nr_blocks = 0;
227 	ll->bitmap_root = 0;
228 	ll->ref_count_root = 0;
229 	ll->bitmap_index_changed = false;
230 
231 	return 0;
232 }
233 
234 int sm_ll_extend(struct ll_disk *ll, dm_block_t extra_blocks)
235 {
236 	int r;
237 	dm_block_t i, nr_blocks, nr_indexes;
238 	unsigned old_blocks, blocks;
239 
240 	nr_blocks = ll->nr_blocks + extra_blocks;
241 	old_blocks = dm_sector_div_up(ll->nr_blocks, ll->entries_per_block);
242 	blocks = dm_sector_div_up(nr_blocks, ll->entries_per_block);
243 
244 	nr_indexes = dm_sector_div_up(nr_blocks, ll->entries_per_block);
245 	if (nr_indexes > ll->max_entries(ll)) {
246 		DMERR("space map too large");
247 		return -EINVAL;
248 	}
249 
250 	/*
251 	 * We need to set this before the dm_tm_new_block() call below.
252 	 */
253 	ll->nr_blocks = nr_blocks;
254 	for (i = old_blocks; i < blocks; i++) {
255 		struct dm_block *b;
256 		struct disk_index_entry idx;
257 
258 		r = dm_tm_new_block(ll->tm, &dm_sm_bitmap_validator, &b);
259 		if (r < 0)
260 			return r;
261 
262 		idx.blocknr = cpu_to_le64(dm_block_location(b));
263 
264 		dm_tm_unlock(ll->tm, b);
265 
266 		idx.nr_free = cpu_to_le32(ll->entries_per_block);
267 		idx.none_free_before = 0;
268 
269 		r = ll->save_ie(ll, i, &idx);
270 		if (r < 0)
271 			return r;
272 	}
273 
274 	return 0;
275 }
276 
277 int sm_ll_lookup_bitmap(struct ll_disk *ll, dm_block_t b, uint32_t *result)
278 {
279 	int r;
280 	dm_block_t index = b;
281 	struct disk_index_entry ie_disk;
282 	struct dm_block *blk;
283 
284 	b = do_div(index, ll->entries_per_block);
285 	r = ll->load_ie(ll, index, &ie_disk);
286 	if (r < 0)
287 		return r;
288 
289 	r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
290 			    &dm_sm_bitmap_validator, &blk);
291 	if (r < 0)
292 		return r;
293 
294 	*result = sm_lookup_bitmap(dm_bitmap_data(blk), b);
295 
296 	dm_tm_unlock(ll->tm, blk);
297 
298 	return 0;
299 }
300 
301 static int sm_ll_lookup_big_ref_count(struct ll_disk *ll, dm_block_t b,
302 				      uint32_t *result)
303 {
304 	__le32 le_rc;
305 	int r;
306 
307 	r = dm_btree_lookup(&ll->ref_count_info, ll->ref_count_root, &b, &le_rc);
308 	if (r < 0)
309 		return r;
310 
311 	*result = le32_to_cpu(le_rc);
312 
313 	return r;
314 }
315 
316 int sm_ll_lookup(struct ll_disk *ll, dm_block_t b, uint32_t *result)
317 {
318 	int r = sm_ll_lookup_bitmap(ll, b, result);
319 
320 	if (r)
321 		return r;
322 
323 	if (*result != 3)
324 		return r;
325 
326 	return sm_ll_lookup_big_ref_count(ll, b, result);
327 }
328 
329 int sm_ll_find_free_block(struct ll_disk *ll, dm_block_t begin,
330 			  dm_block_t end, dm_block_t *result)
331 {
332 	int r;
333 	struct disk_index_entry ie_disk;
334 	dm_block_t i, index_begin = begin;
335 	dm_block_t index_end = dm_sector_div_up(end, ll->entries_per_block);
336 
337 	/*
338 	 * FIXME: Use shifts
339 	 */
340 	begin = do_div(index_begin, ll->entries_per_block);
341 	end = do_div(end, ll->entries_per_block);
342 	if (end == 0)
343 		end = ll->entries_per_block;
344 
345 	for (i = index_begin; i < index_end; i++, begin = 0) {
346 		struct dm_block *blk;
347 		unsigned position;
348 		uint32_t bit_end;
349 
350 		r = ll->load_ie(ll, i, &ie_disk);
351 		if (r < 0)
352 			return r;
353 
354 		if (le32_to_cpu(ie_disk.nr_free) == 0)
355 			continue;
356 
357 		r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
358 				    &dm_sm_bitmap_validator, &blk);
359 		if (r < 0)
360 			return r;
361 
362 		bit_end = (i == index_end - 1) ?  end : ll->entries_per_block;
363 
364 		r = sm_find_free(dm_bitmap_data(blk),
365 				 max_t(unsigned, begin, le32_to_cpu(ie_disk.none_free_before)),
366 				 bit_end, &position);
367 		if (r == -ENOSPC) {
368 			/*
369 			 * This might happen because we started searching
370 			 * part way through the bitmap.
371 			 */
372 			dm_tm_unlock(ll->tm, blk);
373 			continue;
374 		}
375 
376 		dm_tm_unlock(ll->tm, blk);
377 
378 		*result = i * ll->entries_per_block + (dm_block_t) position;
379 		return 0;
380 	}
381 
382 	return -ENOSPC;
383 }
384 
385 int sm_ll_find_common_free_block(struct ll_disk *old_ll, struct ll_disk *new_ll,
386 	                         dm_block_t begin, dm_block_t end, dm_block_t *b)
387 {
388 	int r;
389 	uint32_t count;
390 
391 	do {
392 		r = sm_ll_find_free_block(new_ll, begin, new_ll->nr_blocks, b);
393 		if (r)
394 			break;
395 
396 		/* double check this block wasn't used in the old transaction */
397 		if (*b >= old_ll->nr_blocks)
398 			count = 0;
399 		else {
400 			r = sm_ll_lookup(old_ll, *b, &count);
401 			if (r)
402 				break;
403 
404 			if (count)
405 				begin = *b + 1;
406 		}
407 	} while (count);
408 
409 	return r;
410 }
411 
412 static int sm_ll_mutate(struct ll_disk *ll, dm_block_t b,
413 			int (*mutator)(void *context, uint32_t old, uint32_t *new),
414 			void *context, enum allocation_event *ev)
415 {
416 	int r;
417 	uint32_t bit, old, ref_count;
418 	struct dm_block *nb;
419 	dm_block_t index = b;
420 	struct disk_index_entry ie_disk;
421 	void *bm_le;
422 	int inc;
423 
424 	bit = do_div(index, ll->entries_per_block);
425 	r = ll->load_ie(ll, index, &ie_disk);
426 	if (r < 0)
427 		return r;
428 
429 	r = dm_tm_shadow_block(ll->tm, le64_to_cpu(ie_disk.blocknr),
430 			       &dm_sm_bitmap_validator, &nb, &inc);
431 	if (r < 0) {
432 		DMERR("dm_tm_shadow_block() failed");
433 		return r;
434 	}
435 	ie_disk.blocknr = cpu_to_le64(dm_block_location(nb));
436 
437 	bm_le = dm_bitmap_data(nb);
438 	old = sm_lookup_bitmap(bm_le, bit);
439 
440 	if (old > 2) {
441 		r = sm_ll_lookup_big_ref_count(ll, b, &old);
442 		if (r < 0) {
443 			dm_tm_unlock(ll->tm, nb);
444 			return r;
445 		}
446 	}
447 
448 	r = mutator(context, old, &ref_count);
449 	if (r) {
450 		dm_tm_unlock(ll->tm, nb);
451 		return r;
452 	}
453 
454 	if (ref_count <= 2) {
455 		sm_set_bitmap(bm_le, bit, ref_count);
456 
457 		dm_tm_unlock(ll->tm, nb);
458 
459 		if (old > 2) {
460 			r = dm_btree_remove(&ll->ref_count_info,
461 					    ll->ref_count_root,
462 					    &b, &ll->ref_count_root);
463 			if (r)
464 				return r;
465 		}
466 
467 	} else {
468 		__le32 le_rc = cpu_to_le32(ref_count);
469 
470 		sm_set_bitmap(bm_le, bit, 3);
471 		dm_tm_unlock(ll->tm, nb);
472 
473 		__dm_bless_for_disk(&le_rc);
474 		r = dm_btree_insert(&ll->ref_count_info, ll->ref_count_root,
475 				    &b, &le_rc, &ll->ref_count_root);
476 		if (r < 0) {
477 			DMERR("ref count insert failed");
478 			return r;
479 		}
480 	}
481 
482 	if (ref_count && !old) {
483 		*ev = SM_ALLOC;
484 		ll->nr_allocated++;
485 		le32_add_cpu(&ie_disk.nr_free, -1);
486 		if (le32_to_cpu(ie_disk.none_free_before) == bit)
487 			ie_disk.none_free_before = cpu_to_le32(bit + 1);
488 
489 	} else if (old && !ref_count) {
490 		*ev = SM_FREE;
491 		ll->nr_allocated--;
492 		le32_add_cpu(&ie_disk.nr_free, 1);
493 		ie_disk.none_free_before = cpu_to_le32(min(le32_to_cpu(ie_disk.none_free_before), bit));
494 	} else
495 		*ev = SM_NONE;
496 
497 	return ll->save_ie(ll, index, &ie_disk);
498 }
499 
500 static int set_ref_count(void *context, uint32_t old, uint32_t *new)
501 {
502 	*new = *((uint32_t *) context);
503 	return 0;
504 }
505 
506 int sm_ll_insert(struct ll_disk *ll, dm_block_t b,
507 		 uint32_t ref_count, enum allocation_event *ev)
508 {
509 	return sm_ll_mutate(ll, b, set_ref_count, &ref_count, ev);
510 }
511 
512 static int inc_ref_count(void *context, uint32_t old, uint32_t *new)
513 {
514 	*new = old + 1;
515 	return 0;
516 }
517 
518 int sm_ll_inc(struct ll_disk *ll, dm_block_t b, enum allocation_event *ev)
519 {
520 	return sm_ll_mutate(ll, b, inc_ref_count, NULL, ev);
521 }
522 
523 static int dec_ref_count(void *context, uint32_t old, uint32_t *new)
524 {
525 	if (!old) {
526 		DMERR_LIMIT("unable to decrement a reference count below 0");
527 		return -EINVAL;
528 	}
529 
530 	*new = old - 1;
531 	return 0;
532 }
533 
534 int sm_ll_dec(struct ll_disk *ll, dm_block_t b, enum allocation_event *ev)
535 {
536 	return sm_ll_mutate(ll, b, dec_ref_count, NULL, ev);
537 }
538 
539 int sm_ll_commit(struct ll_disk *ll)
540 {
541 	int r = 0;
542 
543 	if (ll->bitmap_index_changed) {
544 		r = ll->commit(ll);
545 		if (!r)
546 			ll->bitmap_index_changed = false;
547 	}
548 
549 	return r;
550 }
551 
552 /*----------------------------------------------------------------*/
553 
554 static int metadata_ll_load_ie(struct ll_disk *ll, dm_block_t index,
555 			       struct disk_index_entry *ie)
556 {
557 	memcpy(ie, ll->mi_le.index + index, sizeof(*ie));
558 	return 0;
559 }
560 
561 static int metadata_ll_save_ie(struct ll_disk *ll, dm_block_t index,
562 			       struct disk_index_entry *ie)
563 {
564 	ll->bitmap_index_changed = true;
565 	memcpy(ll->mi_le.index + index, ie, sizeof(*ie));
566 	return 0;
567 }
568 
569 static int metadata_ll_init_index(struct ll_disk *ll)
570 {
571 	int r;
572 	struct dm_block *b;
573 
574 	r = dm_tm_new_block(ll->tm, &index_validator, &b);
575 	if (r < 0)
576 		return r;
577 
578 	ll->bitmap_root = dm_block_location(b);
579 
580 	dm_tm_unlock(ll->tm, b);
581 
582 	return 0;
583 }
584 
585 static int metadata_ll_open(struct ll_disk *ll)
586 {
587 	int r;
588 	struct dm_block *block;
589 
590 	r = dm_tm_read_lock(ll->tm, ll->bitmap_root,
591 			    &index_validator, &block);
592 	if (r)
593 		return r;
594 
595 	memcpy(&ll->mi_le, dm_block_data(block), sizeof(ll->mi_le));
596 	dm_tm_unlock(ll->tm, block);
597 
598 	return 0;
599 }
600 
601 static dm_block_t metadata_ll_max_entries(struct ll_disk *ll)
602 {
603 	return MAX_METADATA_BITMAPS;
604 }
605 
606 static int metadata_ll_commit(struct ll_disk *ll)
607 {
608 	int r, inc;
609 	struct dm_block *b;
610 
611 	r = dm_tm_shadow_block(ll->tm, ll->bitmap_root, &index_validator, &b, &inc);
612 	if (r)
613 		return r;
614 
615 	memcpy(dm_block_data(b), &ll->mi_le, sizeof(ll->mi_le));
616 	ll->bitmap_root = dm_block_location(b);
617 
618 	dm_tm_unlock(ll->tm, b);
619 
620 	return 0;
621 }
622 
623 int sm_ll_new_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm)
624 {
625 	int r;
626 
627 	r = sm_ll_init(ll, tm);
628 	if (r < 0)
629 		return r;
630 
631 	ll->load_ie = metadata_ll_load_ie;
632 	ll->save_ie = metadata_ll_save_ie;
633 	ll->init_index = metadata_ll_init_index;
634 	ll->open_index = metadata_ll_open;
635 	ll->max_entries = metadata_ll_max_entries;
636 	ll->commit = metadata_ll_commit;
637 
638 	ll->nr_blocks = 0;
639 	ll->nr_allocated = 0;
640 
641 	r = ll->init_index(ll);
642 	if (r < 0)
643 		return r;
644 
645 	r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
646 	if (r < 0)
647 		return r;
648 
649 	return 0;
650 }
651 
652 int sm_ll_open_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm,
653 			void *root_le, size_t len)
654 {
655 	int r;
656 	struct disk_sm_root smr;
657 
658 	if (len < sizeof(struct disk_sm_root)) {
659 		DMERR("sm_metadata root too small");
660 		return -ENOMEM;
661 	}
662 
663 	/*
664 	 * We don't know the alignment of the root_le buffer, so need to
665 	 * copy into a new structure.
666 	 */
667 	memcpy(&smr, root_le, sizeof(smr));
668 
669 	r = sm_ll_init(ll, tm);
670 	if (r < 0)
671 		return r;
672 
673 	ll->load_ie = metadata_ll_load_ie;
674 	ll->save_ie = metadata_ll_save_ie;
675 	ll->init_index = metadata_ll_init_index;
676 	ll->open_index = metadata_ll_open;
677 	ll->max_entries = metadata_ll_max_entries;
678 	ll->commit = metadata_ll_commit;
679 
680 	ll->nr_blocks = le64_to_cpu(smr.nr_blocks);
681 	ll->nr_allocated = le64_to_cpu(smr.nr_allocated);
682 	ll->bitmap_root = le64_to_cpu(smr.bitmap_root);
683 	ll->ref_count_root = le64_to_cpu(smr.ref_count_root);
684 
685 	return ll->open_index(ll);
686 }
687 
688 /*----------------------------------------------------------------*/
689 
690 static int disk_ll_load_ie(struct ll_disk *ll, dm_block_t index,
691 			   struct disk_index_entry *ie)
692 {
693 	return dm_btree_lookup(&ll->bitmap_info, ll->bitmap_root, &index, ie);
694 }
695 
696 static int disk_ll_save_ie(struct ll_disk *ll, dm_block_t index,
697 			   struct disk_index_entry *ie)
698 {
699 	__dm_bless_for_disk(ie);
700 	return dm_btree_insert(&ll->bitmap_info, ll->bitmap_root,
701 			       &index, ie, &ll->bitmap_root);
702 }
703 
704 static int disk_ll_init_index(struct ll_disk *ll)
705 {
706 	return dm_btree_empty(&ll->bitmap_info, &ll->bitmap_root);
707 }
708 
709 static int disk_ll_open(struct ll_disk *ll)
710 {
711 	/* nothing to do */
712 	return 0;
713 }
714 
715 static dm_block_t disk_ll_max_entries(struct ll_disk *ll)
716 {
717 	return -1ULL;
718 }
719 
720 static int disk_ll_commit(struct ll_disk *ll)
721 {
722 	return 0;
723 }
724 
725 int sm_ll_new_disk(struct ll_disk *ll, struct dm_transaction_manager *tm)
726 {
727 	int r;
728 
729 	r = sm_ll_init(ll, tm);
730 	if (r < 0)
731 		return r;
732 
733 	ll->load_ie = disk_ll_load_ie;
734 	ll->save_ie = disk_ll_save_ie;
735 	ll->init_index = disk_ll_init_index;
736 	ll->open_index = disk_ll_open;
737 	ll->max_entries = disk_ll_max_entries;
738 	ll->commit = disk_ll_commit;
739 
740 	ll->nr_blocks = 0;
741 	ll->nr_allocated = 0;
742 
743 	r = ll->init_index(ll);
744 	if (r < 0)
745 		return r;
746 
747 	r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
748 	if (r < 0)
749 		return r;
750 
751 	return 0;
752 }
753 
754 int sm_ll_open_disk(struct ll_disk *ll, struct dm_transaction_manager *tm,
755 		    void *root_le, size_t len)
756 {
757 	int r;
758 	struct disk_sm_root *smr = root_le;
759 
760 	if (len < sizeof(struct disk_sm_root)) {
761 		DMERR("sm_metadata root too small");
762 		return -ENOMEM;
763 	}
764 
765 	r = sm_ll_init(ll, tm);
766 	if (r < 0)
767 		return r;
768 
769 	ll->load_ie = disk_ll_load_ie;
770 	ll->save_ie = disk_ll_save_ie;
771 	ll->init_index = disk_ll_init_index;
772 	ll->open_index = disk_ll_open;
773 	ll->max_entries = disk_ll_max_entries;
774 	ll->commit = disk_ll_commit;
775 
776 	ll->nr_blocks = le64_to_cpu(smr->nr_blocks);
777 	ll->nr_allocated = le64_to_cpu(smr->nr_allocated);
778 	ll->bitmap_root = le64_to_cpu(smr->bitmap_root);
779 	ll->ref_count_root = le64_to_cpu(smr->ref_count_root);
780 
781 	return ll->open_index(ll);
782 }
783 
784 /*----------------------------------------------------------------*/
785