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3241b1d3 JT |
1 | /* |
2 | * Copyright (C) 2011 Red Hat, Inc. | |
3 | * | |
4 | * This file is released under the GPL. | |
5 | */ | |
6 | ||
7 | #include "dm-btree-internal.h" | |
8 | #include "dm-space-map.h" | |
9 | #include "dm-transaction-manager.h" | |
10 | ||
11 | #include <linux/module.h> | |
12 | #include <linux/device-mapper.h> | |
13 | ||
14 | #define DM_MSG_PREFIX "btree" | |
15 | ||
16 | /*---------------------------------------------------------------- | |
17 | * Array manipulation | |
18 | *--------------------------------------------------------------*/ | |
19 | static void memcpy_disk(void *dest, const void *src, size_t len) | |
20 | __dm_written_to_disk(src) | |
21 | { | |
22 | memcpy(dest, src, len); | |
23 | __dm_unbless_for_disk(src); | |
24 | } | |
25 | ||
26 | static void array_insert(void *base, size_t elt_size, unsigned nr_elts, | |
27 | unsigned index, void *elt) | |
28 | __dm_written_to_disk(elt) | |
29 | { | |
30 | if (index < nr_elts) | |
31 | memmove(base + (elt_size * (index + 1)), | |
32 | base + (elt_size * index), | |
33 | (nr_elts - index) * elt_size); | |
34 | ||
35 | memcpy_disk(base + (elt_size * index), elt, elt_size); | |
36 | } | |
37 | ||
38 | /*----------------------------------------------------------------*/ | |
39 | ||
40 | /* makes the assumption that no two keys are the same. */ | |
41 | static int bsearch(struct node *n, uint64_t key, int want_hi) | |
42 | { | |
43 | int lo = -1, hi = le32_to_cpu(n->header.nr_entries); | |
44 | ||
45 | while (hi - lo > 1) { | |
46 | int mid = lo + ((hi - lo) / 2); | |
47 | uint64_t mid_key = le64_to_cpu(n->keys[mid]); | |
48 | ||
49 | if (mid_key == key) | |
50 | return mid; | |
51 | ||
52 | if (mid_key < key) | |
53 | lo = mid; | |
54 | else | |
55 | hi = mid; | |
56 | } | |
57 | ||
58 | return want_hi ? hi : lo; | |
59 | } | |
60 | ||
61 | int lower_bound(struct node *n, uint64_t key) | |
62 | { | |
63 | return bsearch(n, key, 0); | |
64 | } | |
65 | ||
66 | void inc_children(struct dm_transaction_manager *tm, struct node *n, | |
67 | struct dm_btree_value_type *vt) | |
68 | { | |
69 | unsigned i; | |
70 | uint32_t nr_entries = le32_to_cpu(n->header.nr_entries); | |
71 | ||
72 | if (le32_to_cpu(n->header.flags) & INTERNAL_NODE) | |
73 | for (i = 0; i < nr_entries; i++) | |
74 | dm_tm_inc(tm, value64(n, i)); | |
75 | else if (vt->inc) | |
76 | for (i = 0; i < nr_entries; i++) | |
77 | vt->inc(vt->context, | |
78 | value_ptr(n, i, vt->size)); | |
79 | } | |
80 | ||
81 | static int insert_at(size_t value_size, struct node *node, unsigned index, | |
82 | uint64_t key, void *value) | |
83 | __dm_written_to_disk(value) | |
84 | { | |
85 | uint32_t nr_entries = le32_to_cpu(node->header.nr_entries); | |
86 | __le64 key_le = cpu_to_le64(key); | |
87 | ||
88 | if (index > nr_entries || | |
89 | index >= le32_to_cpu(node->header.max_entries)) { | |
90 | DMERR("too many entries in btree node for insert"); | |
91 | __dm_unbless_for_disk(value); | |
92 | return -ENOMEM; | |
93 | } | |
94 | ||
95 | __dm_bless_for_disk(&key_le); | |
96 | ||
97 | array_insert(node->keys, sizeof(*node->keys), nr_entries, index, &key_le); | |
98 | array_insert(value_base(node), value_size, nr_entries, index, value); | |
99 | node->header.nr_entries = cpu_to_le32(nr_entries + 1); | |
100 | ||
101 | return 0; | |
102 | } | |
103 | ||
104 | /*----------------------------------------------------------------*/ | |
105 | ||
106 | /* | |
107 | * We want 3n entries (for some n). This works more nicely for repeated | |
108 | * insert remove loops than (2n + 1). | |
109 | */ | |
110 | static uint32_t calc_max_entries(size_t value_size, size_t block_size) | |
111 | { | |
112 | uint32_t total, n; | |
113 | size_t elt_size = sizeof(uint64_t) + value_size; /* key + value */ | |
114 | ||
115 | block_size -= sizeof(struct node_header); | |
116 | total = block_size / elt_size; | |
117 | n = total / 3; /* rounds down */ | |
118 | ||
119 | return 3 * n; | |
120 | } | |
121 | ||
122 | int dm_btree_empty(struct dm_btree_info *info, dm_block_t *root) | |
123 | { | |
124 | int r; | |
125 | struct dm_block *b; | |
126 | struct node *n; | |
127 | size_t block_size; | |
128 | uint32_t max_entries; | |
129 | ||
130 | r = new_block(info, &b); | |
131 | if (r < 0) | |
132 | return r; | |
133 | ||
134 | block_size = dm_bm_block_size(dm_tm_get_bm(info->tm)); | |
135 | max_entries = calc_max_entries(info->value_type.size, block_size); | |
136 | ||
137 | n = dm_block_data(b); | |
138 | memset(n, 0, block_size); | |
139 | n->header.flags = cpu_to_le32(LEAF_NODE); | |
140 | n->header.nr_entries = cpu_to_le32(0); | |
141 | n->header.max_entries = cpu_to_le32(max_entries); | |
142 | n->header.value_size = cpu_to_le32(info->value_type.size); | |
143 | ||
144 | *root = dm_block_location(b); | |
145 | return unlock_block(info, b); | |
146 | } | |
147 | EXPORT_SYMBOL_GPL(dm_btree_empty); | |
148 | ||
149 | /*----------------------------------------------------------------*/ | |
150 | ||
151 | /* | |
152 | * Deletion uses a recursive algorithm, since we have limited stack space | |
153 | * we explicitly manage our own stack on the heap. | |
154 | */ | |
155 | #define MAX_SPINE_DEPTH 64 | |
156 | struct frame { | |
157 | struct dm_block *b; | |
158 | struct node *n; | |
159 | unsigned level; | |
160 | unsigned nr_children; | |
161 | unsigned current_child; | |
162 | }; | |
163 | ||
164 | struct del_stack { | |
165 | struct dm_transaction_manager *tm; | |
166 | int top; | |
167 | struct frame spine[MAX_SPINE_DEPTH]; | |
168 | }; | |
169 | ||
170 | static int top_frame(struct del_stack *s, struct frame **f) | |
171 | { | |
172 | if (s->top < 0) { | |
173 | DMERR("btree deletion stack empty"); | |
174 | return -EINVAL; | |
175 | } | |
176 | ||
177 | *f = s->spine + s->top; | |
178 | ||
179 | return 0; | |
180 | } | |
181 | ||
182 | static int unprocessed_frames(struct del_stack *s) | |
183 | { | |
184 | return s->top >= 0; | |
185 | } | |
186 | ||
187 | static int push_frame(struct del_stack *s, dm_block_t b, unsigned level) | |
188 | { | |
189 | int r; | |
190 | uint32_t ref_count; | |
191 | ||
192 | if (s->top >= MAX_SPINE_DEPTH - 1) { | |
193 | DMERR("btree deletion stack out of memory"); | |
194 | return -ENOMEM; | |
195 | } | |
196 | ||
197 | r = dm_tm_ref(s->tm, b, &ref_count); | |
198 | if (r) | |
199 | return r; | |
200 | ||
201 | if (ref_count > 1) | |
202 | /* | |
203 | * This is a shared node, so we can just decrement it's | |
204 | * reference counter and leave the children. | |
205 | */ | |
206 | dm_tm_dec(s->tm, b); | |
207 | ||
208 | else { | |
209 | struct frame *f = s->spine + ++s->top; | |
210 | ||
211 | r = dm_tm_read_lock(s->tm, b, &btree_node_validator, &f->b); | |
212 | if (r) { | |
213 | s->top--; | |
214 | return r; | |
215 | } | |
216 | ||
217 | f->n = dm_block_data(f->b); | |
218 | f->level = level; | |
219 | f->nr_children = le32_to_cpu(f->n->header.nr_entries); | |
220 | f->current_child = 0; | |
221 | } | |
222 | ||
223 | return 0; | |
224 | } | |
225 | ||
226 | static void pop_frame(struct del_stack *s) | |
227 | { | |
228 | struct frame *f = s->spine + s->top--; | |
229 | ||
230 | dm_tm_dec(s->tm, dm_block_location(f->b)); | |
231 | dm_tm_unlock(s->tm, f->b); | |
232 | } | |
233 | ||
234 | int dm_btree_del(struct dm_btree_info *info, dm_block_t root) | |
235 | { | |
236 | int r; | |
237 | struct del_stack *s; | |
238 | ||
239 | s = kmalloc(sizeof(*s), GFP_KERNEL); | |
240 | if (!s) | |
241 | return -ENOMEM; | |
242 | s->tm = info->tm; | |
243 | s->top = -1; | |
244 | ||
245 | r = push_frame(s, root, 1); | |
246 | if (r) | |
247 | goto out; | |
248 | ||
249 | while (unprocessed_frames(s)) { | |
250 | uint32_t flags; | |
251 | struct frame *f; | |
252 | dm_block_t b; | |
253 | ||
254 | r = top_frame(s, &f); | |
255 | if (r) | |
256 | goto out; | |
257 | ||
258 | if (f->current_child >= f->nr_children) { | |
259 | pop_frame(s); | |
260 | continue; | |
261 | } | |
262 | ||
263 | flags = le32_to_cpu(f->n->header.flags); | |
264 | if (flags & INTERNAL_NODE) { | |
265 | b = value64(f->n, f->current_child); | |
266 | f->current_child++; | |
267 | r = push_frame(s, b, f->level); | |
268 | if (r) | |
269 | goto out; | |
270 | ||
271 | } else if (f->level != (info->levels - 1)) { | |
272 | b = value64(f->n, f->current_child); | |
273 | f->current_child++; | |
274 | r = push_frame(s, b, f->level + 1); | |
275 | if (r) | |
276 | goto out; | |
277 | ||
278 | } else { | |
279 | if (info->value_type.dec) { | |
280 | unsigned i; | |
281 | ||
282 | for (i = 0; i < f->nr_children; i++) | |
283 | info->value_type.dec(info->value_type.context, | |
284 | value_ptr(f->n, i, info->value_type.size)); | |
285 | } | |
286 | f->current_child = f->nr_children; | |
287 | } | |
288 | } | |
289 | ||
290 | out: | |
291 | kfree(s); | |
292 | return r; | |
293 | } | |
294 | EXPORT_SYMBOL_GPL(dm_btree_del); | |
295 | ||
296 | /*----------------------------------------------------------------*/ | |
297 | ||
298 | static int btree_lookup_raw(struct ro_spine *s, dm_block_t block, uint64_t key, | |
299 | int (*search_fn)(struct node *, uint64_t), | |
300 | uint64_t *result_key, void *v, size_t value_size) | |
301 | { | |
302 | int i, r; | |
303 | uint32_t flags, nr_entries; | |
304 | ||
305 | do { | |
306 | r = ro_step(s, block); | |
307 | if (r < 0) | |
308 | return r; | |
309 | ||
310 | i = search_fn(ro_node(s), key); | |
311 | ||
312 | flags = le32_to_cpu(ro_node(s)->header.flags); | |
313 | nr_entries = le32_to_cpu(ro_node(s)->header.nr_entries); | |
314 | if (i < 0 || i >= nr_entries) | |
315 | return -ENODATA; | |
316 | ||
317 | if (flags & INTERNAL_NODE) | |
318 | block = value64(ro_node(s), i); | |
319 | ||
320 | } while (!(flags & LEAF_NODE)); | |
321 | ||
322 | *result_key = le64_to_cpu(ro_node(s)->keys[i]); | |
323 | memcpy(v, value_ptr(ro_node(s), i, value_size), value_size); | |
324 | ||
325 | return 0; | |
326 | } | |
327 | ||
328 | int dm_btree_lookup(struct dm_btree_info *info, dm_block_t root, | |
329 | uint64_t *keys, void *value_le) | |
330 | { | |
331 | unsigned level, last_level = info->levels - 1; | |
332 | int r = -ENODATA; | |
333 | uint64_t rkey; | |
334 | __le64 internal_value_le; | |
335 | struct ro_spine spine; | |
336 | ||
337 | init_ro_spine(&spine, info); | |
338 | for (level = 0; level < info->levels; level++) { | |
339 | size_t size; | |
340 | void *value_p; | |
341 | ||
342 | if (level == last_level) { | |
343 | value_p = value_le; | |
344 | size = info->value_type.size; | |
345 | ||
346 | } else { | |
347 | value_p = &internal_value_le; | |
348 | size = sizeof(uint64_t); | |
349 | } | |
350 | ||
351 | r = btree_lookup_raw(&spine, root, keys[level], | |
352 | lower_bound, &rkey, | |
353 | value_p, size); | |
354 | ||
355 | if (!r) { | |
356 | if (rkey != keys[level]) { | |
357 | exit_ro_spine(&spine); | |
358 | return -ENODATA; | |
359 | } | |
360 | } else { | |
361 | exit_ro_spine(&spine); | |
362 | return r; | |
363 | } | |
364 | ||
365 | root = le64_to_cpu(internal_value_le); | |
366 | } | |
367 | exit_ro_spine(&spine); | |
368 | ||
369 | return r; | |
370 | } | |
371 | EXPORT_SYMBOL_GPL(dm_btree_lookup); | |
372 | ||
373 | /* | |
374 | * Splits a node by creating a sibling node and shifting half the nodes | |
375 | * contents across. Assumes there is a parent node, and it has room for | |
376 | * another child. | |
377 | * | |
378 | * Before: | |
379 | * +--------+ | |
380 | * | Parent | | |
381 | * +--------+ | |
382 | * | | |
383 | * v | |
384 | * +----------+ | |
385 | * | A ++++++ | | |
386 | * +----------+ | |
387 | * | |
388 | * | |
389 | * After: | |
390 | * +--------+ | |
391 | * | Parent | | |
392 | * +--------+ | |
393 | * | | | |
394 | * v +------+ | |
395 | * +---------+ | | |
396 | * | A* +++ | v | |
397 | * +---------+ +-------+ | |
398 | * | B +++ | | |
399 | * +-------+ | |
400 | * | |
401 | * Where A* is a shadow of A. | |
402 | */ | |
403 | static int btree_split_sibling(struct shadow_spine *s, dm_block_t root, | |
404 | unsigned parent_index, uint64_t key) | |
405 | { | |
406 | int r; | |
407 | size_t size; | |
408 | unsigned nr_left, nr_right; | |
409 | struct dm_block *left, *right, *parent; | |
410 | struct node *ln, *rn, *pn; | |
411 | __le64 location; | |
412 | ||
413 | left = shadow_current(s); | |
414 | ||
415 | r = new_block(s->info, &right); | |
416 | if (r < 0) | |
417 | return r; | |
418 | ||
419 | ln = dm_block_data(left); | |
420 | rn = dm_block_data(right); | |
421 | ||
422 | nr_left = le32_to_cpu(ln->header.nr_entries) / 2; | |
423 | nr_right = le32_to_cpu(ln->header.nr_entries) - nr_left; | |
424 | ||
425 | ln->header.nr_entries = cpu_to_le32(nr_left); | |
426 | ||
427 | rn->header.flags = ln->header.flags; | |
428 | rn->header.nr_entries = cpu_to_le32(nr_right); | |
429 | rn->header.max_entries = ln->header.max_entries; | |
430 | rn->header.value_size = ln->header.value_size; | |
431 | memcpy(rn->keys, ln->keys + nr_left, nr_right * sizeof(rn->keys[0])); | |
432 | ||
433 | size = le32_to_cpu(ln->header.flags) & INTERNAL_NODE ? | |
434 | sizeof(uint64_t) : s->info->value_type.size; | |
435 | memcpy(value_ptr(rn, 0, size), value_ptr(ln, nr_left, size), | |
436 | size * nr_right); | |
437 | ||
438 | /* | |
439 | * Patch up the parent | |
440 | */ | |
441 | parent = shadow_parent(s); | |
442 | ||
443 | pn = dm_block_data(parent); | |
444 | location = cpu_to_le64(dm_block_location(left)); | |
445 | __dm_bless_for_disk(&location); | |
446 | memcpy_disk(value_ptr(pn, parent_index, sizeof(__le64)), | |
447 | &location, sizeof(__le64)); | |
448 | ||
449 | location = cpu_to_le64(dm_block_location(right)); | |
450 | __dm_bless_for_disk(&location); | |
451 | ||
452 | r = insert_at(sizeof(__le64), pn, parent_index + 1, | |
453 | le64_to_cpu(rn->keys[0]), &location); | |
454 | if (r) | |
455 | return r; | |
456 | ||
457 | if (key < le64_to_cpu(rn->keys[0])) { | |
458 | unlock_block(s->info, right); | |
459 | s->nodes[1] = left; | |
460 | } else { | |
461 | unlock_block(s->info, left); | |
462 | s->nodes[1] = right; | |
463 | } | |
464 | ||
465 | return 0; | |
466 | } | |
467 | ||
468 | /* | |
469 | * Splits a node by creating two new children beneath the given node. | |
470 | * | |
471 | * Before: | |
472 | * +----------+ | |
473 | * | A ++++++ | | |
474 | * +----------+ | |
475 | * | |
476 | * | |
477 | * After: | |
478 | * +------------+ | |
479 | * | A (shadow) | | |
480 | * +------------+ | |
481 | * | | | |
482 | * +------+ +----+ | |
483 | * | | | |
484 | * v v | |
485 | * +-------+ +-------+ | |
486 | * | B +++ | | C +++ | | |
487 | * +-------+ +-------+ | |
488 | */ | |
489 | static int btree_split_beneath(struct shadow_spine *s, uint64_t key) | |
490 | { | |
491 | int r; | |
492 | size_t size; | |
493 | unsigned nr_left, nr_right; | |
494 | struct dm_block *left, *right, *new_parent; | |
495 | struct node *pn, *ln, *rn; | |
496 | __le64 val; | |
497 | ||
498 | new_parent = shadow_current(s); | |
499 | ||
500 | r = new_block(s->info, &left); | |
501 | if (r < 0) | |
502 | return r; | |
503 | ||
504 | r = new_block(s->info, &right); | |
505 | if (r < 0) { | |
506 | /* FIXME: put left */ | |
507 | return r; | |
508 | } | |
509 | ||
510 | pn = dm_block_data(new_parent); | |
511 | ln = dm_block_data(left); | |
512 | rn = dm_block_data(right); | |
513 | ||
514 | nr_left = le32_to_cpu(pn->header.nr_entries) / 2; | |
515 | nr_right = le32_to_cpu(pn->header.nr_entries) - nr_left; | |
516 | ||
517 | ln->header.flags = pn->header.flags; | |
518 | ln->header.nr_entries = cpu_to_le32(nr_left); | |
519 | ln->header.max_entries = pn->header.max_entries; | |
520 | ln->header.value_size = pn->header.value_size; | |
521 | ||
522 | rn->header.flags = pn->header.flags; | |
523 | rn->header.nr_entries = cpu_to_le32(nr_right); | |
524 | rn->header.max_entries = pn->header.max_entries; | |
525 | rn->header.value_size = pn->header.value_size; | |
526 | ||
527 | memcpy(ln->keys, pn->keys, nr_left * sizeof(pn->keys[0])); | |
528 | memcpy(rn->keys, pn->keys + nr_left, nr_right * sizeof(pn->keys[0])); | |
529 | ||
530 | size = le32_to_cpu(pn->header.flags) & INTERNAL_NODE ? | |
531 | sizeof(__le64) : s->info->value_type.size; | |
532 | memcpy(value_ptr(ln, 0, size), value_ptr(pn, 0, size), nr_left * size); | |
533 | memcpy(value_ptr(rn, 0, size), value_ptr(pn, nr_left, size), | |
534 | nr_right * size); | |
535 | ||
536 | /* new_parent should just point to l and r now */ | |
537 | pn->header.flags = cpu_to_le32(INTERNAL_NODE); | |
538 | pn->header.nr_entries = cpu_to_le32(2); | |
539 | pn->header.max_entries = cpu_to_le32( | |
540 | calc_max_entries(sizeof(__le64), | |
541 | dm_bm_block_size( | |
542 | dm_tm_get_bm(s->info->tm)))); | |
543 | pn->header.value_size = cpu_to_le32(sizeof(__le64)); | |
544 | ||
545 | val = cpu_to_le64(dm_block_location(left)); | |
546 | __dm_bless_for_disk(&val); | |
547 | pn->keys[0] = ln->keys[0]; | |
548 | memcpy_disk(value_ptr(pn, 0, sizeof(__le64)), &val, sizeof(__le64)); | |
549 | ||
550 | val = cpu_to_le64(dm_block_location(right)); | |
551 | __dm_bless_for_disk(&val); | |
552 | pn->keys[1] = rn->keys[0]; | |
553 | memcpy_disk(value_ptr(pn, 1, sizeof(__le64)), &val, sizeof(__le64)); | |
554 | ||
555 | /* | |
556 | * rejig the spine. This is ugly, since it knows too | |
557 | * much about the spine | |
558 | */ | |
559 | if (s->nodes[0] != new_parent) { | |
560 | unlock_block(s->info, s->nodes[0]); | |
561 | s->nodes[0] = new_parent; | |
562 | } | |
563 | if (key < le64_to_cpu(rn->keys[0])) { | |
564 | unlock_block(s->info, right); | |
565 | s->nodes[1] = left; | |
566 | } else { | |
567 | unlock_block(s->info, left); | |
568 | s->nodes[1] = right; | |
569 | } | |
570 | s->count = 2; | |
571 | ||
572 | return 0; | |
573 | } | |
574 | ||
575 | static int btree_insert_raw(struct shadow_spine *s, dm_block_t root, | |
576 | struct dm_btree_value_type *vt, | |
577 | uint64_t key, unsigned *index) | |
578 | { | |
579 | int r, i = *index, top = 1; | |
580 | struct node *node; | |
581 | ||
582 | for (;;) { | |
583 | r = shadow_step(s, root, vt); | |
584 | if (r < 0) | |
585 | return r; | |
586 | ||
587 | node = dm_block_data(shadow_current(s)); | |
588 | ||
589 | /* | |
590 | * We have to patch up the parent node, ugly, but I don't | |
591 | * see a way to do this automatically as part of the spine | |
592 | * op. | |
593 | */ | |
594 | if (shadow_has_parent(s) && i >= 0) { /* FIXME: second clause unness. */ | |
595 | __le64 location = cpu_to_le64(dm_block_location(shadow_current(s))); | |
596 | ||
597 | __dm_bless_for_disk(&location); | |
598 | memcpy_disk(value_ptr(dm_block_data(shadow_parent(s)), i, sizeof(uint64_t)), | |
599 | &location, sizeof(__le64)); | |
600 | } | |
601 | ||
602 | node = dm_block_data(shadow_current(s)); | |
603 | ||
604 | if (node->header.nr_entries == node->header.max_entries) { | |
605 | if (top) | |
606 | r = btree_split_beneath(s, key); | |
607 | else | |
608 | r = btree_split_sibling(s, root, i, key); | |
609 | ||
610 | if (r < 0) | |
611 | return r; | |
612 | } | |
613 | ||
614 | node = dm_block_data(shadow_current(s)); | |
615 | ||
616 | i = lower_bound(node, key); | |
617 | ||
618 | if (le32_to_cpu(node->header.flags) & LEAF_NODE) | |
619 | break; | |
620 | ||
621 | if (i < 0) { | |
622 | /* change the bounds on the lowest key */ | |
623 | node->keys[0] = cpu_to_le64(key); | |
624 | i = 0; | |
625 | } | |
626 | ||
627 | root = value64(node, i); | |
628 | top = 0; | |
629 | } | |
630 | ||
631 | if (i < 0 || le64_to_cpu(node->keys[i]) != key) | |
632 | i++; | |
633 | ||
634 | *index = i; | |
635 | return 0; | |
636 | } | |
637 | ||
638 | static int insert(struct dm_btree_info *info, dm_block_t root, | |
639 | uint64_t *keys, void *value, dm_block_t *new_root, | |
640 | int *inserted) | |
641 | __dm_written_to_disk(value) | |
642 | { | |
643 | int r, need_insert; | |
644 | unsigned level, index = -1, last_level = info->levels - 1; | |
645 | dm_block_t block = root; | |
646 | struct shadow_spine spine; | |
647 | struct node *n; | |
648 | struct dm_btree_value_type le64_type; | |
649 | ||
650 | le64_type.context = NULL; | |
651 | le64_type.size = sizeof(__le64); | |
652 | le64_type.inc = NULL; | |
653 | le64_type.dec = NULL; | |
654 | le64_type.equal = NULL; | |
655 | ||
656 | init_shadow_spine(&spine, info); | |
657 | ||
658 | for (level = 0; level < (info->levels - 1); level++) { | |
659 | r = btree_insert_raw(&spine, block, &le64_type, keys[level], &index); | |
660 | if (r < 0) | |
661 | goto bad; | |
662 | ||
663 | n = dm_block_data(shadow_current(&spine)); | |
664 | need_insert = ((index >= le32_to_cpu(n->header.nr_entries)) || | |
665 | (le64_to_cpu(n->keys[index]) != keys[level])); | |
666 | ||
667 | if (need_insert) { | |
668 | dm_block_t new_tree; | |
669 | __le64 new_le; | |
670 | ||
671 | r = dm_btree_empty(info, &new_tree); | |
672 | if (r < 0) | |
673 | goto bad; | |
674 | ||
675 | new_le = cpu_to_le64(new_tree); | |
676 | __dm_bless_for_disk(&new_le); | |
677 | ||
678 | r = insert_at(sizeof(uint64_t), n, index, | |
679 | keys[level], &new_le); | |
680 | if (r) | |
681 | goto bad; | |
682 | } | |
683 | ||
684 | if (level < last_level) | |
685 | block = value64(n, index); | |
686 | } | |
687 | ||
688 | r = btree_insert_raw(&spine, block, &info->value_type, | |
689 | keys[level], &index); | |
690 | if (r < 0) | |
691 | goto bad; | |
692 | ||
693 | n = dm_block_data(shadow_current(&spine)); | |
694 | need_insert = ((index >= le32_to_cpu(n->header.nr_entries)) || | |
695 | (le64_to_cpu(n->keys[index]) != keys[level])); | |
696 | ||
697 | if (need_insert) { | |
698 | if (inserted) | |
699 | *inserted = 1; | |
700 | ||
701 | r = insert_at(info->value_type.size, n, index, | |
702 | keys[level], value); | |
703 | if (r) | |
704 | goto bad_unblessed; | |
705 | } else { | |
706 | if (inserted) | |
707 | *inserted = 0; | |
708 | ||
709 | if (info->value_type.dec && | |
710 | (!info->value_type.equal || | |
711 | !info->value_type.equal( | |
712 | info->value_type.context, | |
713 | value_ptr(n, index, info->value_type.size), | |
714 | value))) { | |
715 | info->value_type.dec(info->value_type.context, | |
716 | value_ptr(n, index, info->value_type.size)); | |
717 | } | |
718 | memcpy_disk(value_ptr(n, index, info->value_type.size), | |
719 | value, info->value_type.size); | |
720 | } | |
721 | ||
722 | *new_root = shadow_root(&spine); | |
723 | exit_shadow_spine(&spine); | |
724 | ||
725 | return 0; | |
726 | ||
727 | bad: | |
728 | __dm_unbless_for_disk(value); | |
729 | bad_unblessed: | |
730 | exit_shadow_spine(&spine); | |
731 | return r; | |
732 | } | |
733 | ||
734 | int dm_btree_insert(struct dm_btree_info *info, dm_block_t root, | |
735 | uint64_t *keys, void *value, dm_block_t *new_root) | |
736 | __dm_written_to_disk(value) | |
737 | { | |
738 | return insert(info, root, keys, value, new_root, NULL); | |
739 | } | |
740 | EXPORT_SYMBOL_GPL(dm_btree_insert); | |
741 | ||
742 | int dm_btree_insert_notify(struct dm_btree_info *info, dm_block_t root, | |
743 | uint64_t *keys, void *value, dm_block_t *new_root, | |
744 | int *inserted) | |
745 | __dm_written_to_disk(value) | |
746 | { | |
747 | return insert(info, root, keys, value, new_root, inserted); | |
748 | } | |
749 | EXPORT_SYMBOL_GPL(dm_btree_insert_notify); | |
750 | ||
751 | /*----------------------------------------------------------------*/ | |
752 | ||
753 | static int find_highest_key(struct ro_spine *s, dm_block_t block, | |
754 | uint64_t *result_key, dm_block_t *next_block) | |
755 | { | |
756 | int i, r; | |
757 | uint32_t flags; | |
758 | ||
759 | do { | |
760 | r = ro_step(s, block); | |
761 | if (r < 0) | |
762 | return r; | |
763 | ||
764 | flags = le32_to_cpu(ro_node(s)->header.flags); | |
765 | i = le32_to_cpu(ro_node(s)->header.nr_entries); | |
766 | if (!i) | |
767 | return -ENODATA; | |
768 | else | |
769 | i--; | |
770 | ||
771 | *result_key = le64_to_cpu(ro_node(s)->keys[i]); | |
772 | if (next_block || flags & INTERNAL_NODE) | |
773 | block = value64(ro_node(s), i); | |
774 | ||
775 | } while (flags & INTERNAL_NODE); | |
776 | ||
777 | if (next_block) | |
778 | *next_block = block; | |
779 | return 0; | |
780 | } | |
781 | ||
782 | int dm_btree_find_highest_key(struct dm_btree_info *info, dm_block_t root, | |
783 | uint64_t *result_keys) | |
784 | { | |
785 | int r = 0, count = 0, level; | |
786 | struct ro_spine spine; | |
787 | ||
788 | init_ro_spine(&spine, info); | |
789 | for (level = 0; level < info->levels; level++) { | |
790 | r = find_highest_key(&spine, root, result_keys + level, | |
791 | level == info->levels - 1 ? NULL : &root); | |
792 | if (r == -ENODATA) { | |
793 | r = 0; | |
794 | break; | |
795 | ||
796 | } else if (r) | |
797 | break; | |
798 | ||
799 | count++; | |
800 | } | |
801 | exit_ro_spine(&spine); | |
802 | ||
803 | return r ? r : count; | |
804 | } | |
805 | EXPORT_SYMBOL_GPL(dm_btree_find_highest_key); |