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Commit | Line | Data |
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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 | ||
1944ce60 | 11 | #include <linux/export.h> |
3241b1d3 JT |
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. */ | |
550929fa | 41 | static int bsearch(struct btree_node *n, uint64_t key, int want_hi) |
3241b1d3 JT |
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 | ||
550929fa | 61 | int lower_bound(struct btree_node *n, uint64_t key) |
3241b1d3 JT |
62 | { |
63 | return bsearch(n, key, 0); | |
64 | } | |
65 | ||
550929fa | 66 | void inc_children(struct dm_transaction_manager *tm, struct btree_node *n, |
3241b1d3 JT |
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++) | |
a3aefb39 | 77 | vt->inc(vt->context, value_ptr(n, i)); |
3241b1d3 JT |
78 | } |
79 | ||
550929fa | 80 | static int insert_at(size_t value_size, struct btree_node *node, unsigned index, |
3241b1d3 JT |
81 | uint64_t key, void *value) |
82 | __dm_written_to_disk(value) | |
83 | { | |
84 | uint32_t nr_entries = le32_to_cpu(node->header.nr_entries); | |
85 | __le64 key_le = cpu_to_le64(key); | |
86 | ||
87 | if (index > nr_entries || | |
88 | index >= le32_to_cpu(node->header.max_entries)) { | |
89 | DMERR("too many entries in btree node for insert"); | |
90 | __dm_unbless_for_disk(value); | |
91 | return -ENOMEM; | |
92 | } | |
93 | ||
94 | __dm_bless_for_disk(&key_le); | |
95 | ||
96 | array_insert(node->keys, sizeof(*node->keys), nr_entries, index, &key_le); | |
97 | array_insert(value_base(node), value_size, nr_entries, index, value); | |
98 | node->header.nr_entries = cpu_to_le32(nr_entries + 1); | |
99 | ||
100 | return 0; | |
101 | } | |
102 | ||
103 | /*----------------------------------------------------------------*/ | |
104 | ||
105 | /* | |
106 | * We want 3n entries (for some n). This works more nicely for repeated | |
107 | * insert remove loops than (2n + 1). | |
108 | */ | |
109 | static uint32_t calc_max_entries(size_t value_size, size_t block_size) | |
110 | { | |
111 | uint32_t total, n; | |
112 | size_t elt_size = sizeof(uint64_t) + value_size; /* key + value */ | |
113 | ||
114 | block_size -= sizeof(struct node_header); | |
115 | total = block_size / elt_size; | |
116 | n = total / 3; /* rounds down */ | |
117 | ||
118 | return 3 * n; | |
119 | } | |
120 | ||
121 | int dm_btree_empty(struct dm_btree_info *info, dm_block_t *root) | |
122 | { | |
123 | int r; | |
124 | struct dm_block *b; | |
550929fa | 125 | struct btree_node *n; |
3241b1d3 JT |
126 | size_t block_size; |
127 | uint32_t max_entries; | |
128 | ||
129 | r = new_block(info, &b); | |
130 | if (r < 0) | |
131 | return r; | |
132 | ||
133 | block_size = dm_bm_block_size(dm_tm_get_bm(info->tm)); | |
134 | max_entries = calc_max_entries(info->value_type.size, block_size); | |
135 | ||
136 | n = dm_block_data(b); | |
137 | memset(n, 0, block_size); | |
138 | n->header.flags = cpu_to_le32(LEAF_NODE); | |
139 | n->header.nr_entries = cpu_to_le32(0); | |
140 | n->header.max_entries = cpu_to_le32(max_entries); | |
141 | n->header.value_size = cpu_to_le32(info->value_type.size); | |
142 | ||
143 | *root = dm_block_location(b); | |
144 | return unlock_block(info, b); | |
145 | } | |
146 | EXPORT_SYMBOL_GPL(dm_btree_empty); | |
147 | ||
148 | /*----------------------------------------------------------------*/ | |
149 | ||
150 | /* | |
151 | * Deletion uses a recursive algorithm, since we have limited stack space | |
152 | * we explicitly manage our own stack on the heap. | |
153 | */ | |
154 | #define MAX_SPINE_DEPTH 64 | |
155 | struct frame { | |
156 | struct dm_block *b; | |
550929fa | 157 | struct btree_node *n; |
3241b1d3 JT |
158 | unsigned level; |
159 | unsigned nr_children; | |
160 | unsigned current_child; | |
161 | }; | |
162 | ||
163 | struct del_stack { | |
04f17c80 | 164 | struct dm_btree_info *info; |
3241b1d3 JT |
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 | ||
04f17c80 JT |
187 | static void prefetch_children(struct del_stack *s, struct frame *f) |
188 | { | |
189 | unsigned i; | |
190 | struct dm_block_manager *bm = dm_tm_get_bm(s->tm); | |
191 | ||
192 | for (i = 0; i < f->nr_children; i++) | |
193 | dm_bm_prefetch(bm, value64(f->n, i)); | |
194 | } | |
195 | ||
196 | static bool is_internal_level(struct dm_btree_info *info, struct frame *f) | |
197 | { | |
198 | return f->level < (info->levels - 1); | |
199 | } | |
200 | ||
3241b1d3 JT |
201 | static int push_frame(struct del_stack *s, dm_block_t b, unsigned level) |
202 | { | |
203 | int r; | |
204 | uint32_t ref_count; | |
205 | ||
206 | if (s->top >= MAX_SPINE_DEPTH - 1) { | |
207 | DMERR("btree deletion stack out of memory"); | |
208 | return -ENOMEM; | |
209 | } | |
210 | ||
211 | r = dm_tm_ref(s->tm, b, &ref_count); | |
212 | if (r) | |
213 | return r; | |
214 | ||
215 | if (ref_count > 1) | |
216 | /* | |
217 | * This is a shared node, so we can just decrement it's | |
218 | * reference counter and leave the children. | |
219 | */ | |
220 | dm_tm_dec(s->tm, b); | |
221 | ||
222 | else { | |
04f17c80 | 223 | uint32_t flags; |
3241b1d3 JT |
224 | struct frame *f = s->spine + ++s->top; |
225 | ||
226 | r = dm_tm_read_lock(s->tm, b, &btree_node_validator, &f->b); | |
227 | if (r) { | |
228 | s->top--; | |
229 | return r; | |
230 | } | |
231 | ||
232 | f->n = dm_block_data(f->b); | |
233 | f->level = level; | |
234 | f->nr_children = le32_to_cpu(f->n->header.nr_entries); | |
235 | f->current_child = 0; | |
04f17c80 JT |
236 | |
237 | flags = le32_to_cpu(f->n->header.flags); | |
238 | if (flags & INTERNAL_NODE || is_internal_level(s->info, f)) | |
239 | prefetch_children(s, f); | |
3241b1d3 JT |
240 | } |
241 | ||
242 | return 0; | |
243 | } | |
244 | ||
245 | static void pop_frame(struct del_stack *s) | |
246 | { | |
247 | struct frame *f = s->spine + s->top--; | |
248 | ||
249 | dm_tm_dec(s->tm, dm_block_location(f->b)); | |
250 | dm_tm_unlock(s->tm, f->b); | |
251 | } | |
252 | ||
253 | int dm_btree_del(struct dm_btree_info *info, dm_block_t root) | |
254 | { | |
255 | int r; | |
256 | struct del_stack *s; | |
257 | ||
1c751879 | 258 | s = kmalloc(sizeof(*s), GFP_NOIO); |
3241b1d3 JT |
259 | if (!s) |
260 | return -ENOMEM; | |
04f17c80 | 261 | s->info = info; |
3241b1d3 JT |
262 | s->tm = info->tm; |
263 | s->top = -1; | |
264 | ||
e3cbf945 | 265 | r = push_frame(s, root, 0); |
3241b1d3 JT |
266 | if (r) |
267 | goto out; | |
268 | ||
269 | while (unprocessed_frames(s)) { | |
270 | uint32_t flags; | |
271 | struct frame *f; | |
272 | dm_block_t b; | |
273 | ||
274 | r = top_frame(s, &f); | |
275 | if (r) | |
276 | goto out; | |
277 | ||
278 | if (f->current_child >= f->nr_children) { | |
279 | pop_frame(s); | |
280 | continue; | |
281 | } | |
282 | ||
283 | flags = le32_to_cpu(f->n->header.flags); | |
284 | if (flags & INTERNAL_NODE) { | |
285 | b = value64(f->n, f->current_child); | |
286 | f->current_child++; | |
287 | r = push_frame(s, b, f->level); | |
288 | if (r) | |
289 | goto out; | |
290 | ||
e3cbf945 | 291 | } else if (is_internal_level(info, f)) { |
3241b1d3 JT |
292 | b = value64(f->n, f->current_child); |
293 | f->current_child++; | |
294 | r = push_frame(s, b, f->level + 1); | |
295 | if (r) | |
296 | goto out; | |
297 | ||
298 | } else { | |
299 | if (info->value_type.dec) { | |
300 | unsigned i; | |
301 | ||
302 | for (i = 0; i < f->nr_children; i++) | |
303 | info->value_type.dec(info->value_type.context, | |
a3aefb39 | 304 | value_ptr(f->n, i)); |
3241b1d3 | 305 | } |
cd5acf0b | 306 | pop_frame(s); |
3241b1d3 JT |
307 | } |
308 | } | |
309 | ||
310 | out: | |
311 | kfree(s); | |
312 | return r; | |
313 | } | |
314 | EXPORT_SYMBOL_GPL(dm_btree_del); | |
315 | ||
316 | /*----------------------------------------------------------------*/ | |
317 | ||
318 | static int btree_lookup_raw(struct ro_spine *s, dm_block_t block, uint64_t key, | |
550929fa | 319 | int (*search_fn)(struct btree_node *, uint64_t), |
3241b1d3 JT |
320 | uint64_t *result_key, void *v, size_t value_size) |
321 | { | |
322 | int i, r; | |
323 | uint32_t flags, nr_entries; | |
324 | ||
325 | do { | |
326 | r = ro_step(s, block); | |
327 | if (r < 0) | |
328 | return r; | |
329 | ||
330 | i = search_fn(ro_node(s), key); | |
331 | ||
332 | flags = le32_to_cpu(ro_node(s)->header.flags); | |
333 | nr_entries = le32_to_cpu(ro_node(s)->header.nr_entries); | |
334 | if (i < 0 || i >= nr_entries) | |
335 | return -ENODATA; | |
336 | ||
337 | if (flags & INTERNAL_NODE) | |
338 | block = value64(ro_node(s), i); | |
339 | ||
340 | } while (!(flags & LEAF_NODE)); | |
341 | ||
342 | *result_key = le64_to_cpu(ro_node(s)->keys[i]); | |
a3aefb39 | 343 | memcpy(v, value_ptr(ro_node(s), i), value_size); |
3241b1d3 JT |
344 | |
345 | return 0; | |
346 | } | |
347 | ||
348 | int dm_btree_lookup(struct dm_btree_info *info, dm_block_t root, | |
349 | uint64_t *keys, void *value_le) | |
350 | { | |
351 | unsigned level, last_level = info->levels - 1; | |
352 | int r = -ENODATA; | |
353 | uint64_t rkey; | |
354 | __le64 internal_value_le; | |
355 | struct ro_spine spine; | |
356 | ||
357 | init_ro_spine(&spine, info); | |
358 | for (level = 0; level < info->levels; level++) { | |
359 | size_t size; | |
360 | void *value_p; | |
361 | ||
362 | if (level == last_level) { | |
363 | value_p = value_le; | |
364 | size = info->value_type.size; | |
365 | ||
366 | } else { | |
367 | value_p = &internal_value_le; | |
368 | size = sizeof(uint64_t); | |
369 | } | |
370 | ||
371 | r = btree_lookup_raw(&spine, root, keys[level], | |
372 | lower_bound, &rkey, | |
373 | value_p, size); | |
374 | ||
375 | if (!r) { | |
376 | if (rkey != keys[level]) { | |
377 | exit_ro_spine(&spine); | |
378 | return -ENODATA; | |
379 | } | |
380 | } else { | |
381 | exit_ro_spine(&spine); | |
382 | return r; | |
383 | } | |
384 | ||
385 | root = le64_to_cpu(internal_value_le); | |
386 | } | |
387 | exit_ro_spine(&spine); | |
388 | ||
389 | return r; | |
390 | } | |
391 | EXPORT_SYMBOL_GPL(dm_btree_lookup); | |
392 | ||
393 | /* | |
394 | * Splits a node by creating a sibling node and shifting half the nodes | |
395 | * contents across. Assumes there is a parent node, and it has room for | |
396 | * another child. | |
397 | * | |
398 | * Before: | |
399 | * +--------+ | |
400 | * | Parent | | |
401 | * +--------+ | |
402 | * | | |
403 | * v | |
404 | * +----------+ | |
405 | * | A ++++++ | | |
406 | * +----------+ | |
407 | * | |
408 | * | |
409 | * After: | |
410 | * +--------+ | |
411 | * | Parent | | |
412 | * +--------+ | |
413 | * | | | |
414 | * v +------+ | |
415 | * +---------+ | | |
416 | * | A* +++ | v | |
417 | * +---------+ +-------+ | |
418 | * | B +++ | | |
419 | * +-------+ | |
420 | * | |
421 | * Where A* is a shadow of A. | |
422 | */ | |
423 | static int btree_split_sibling(struct shadow_spine *s, dm_block_t root, | |
424 | unsigned parent_index, uint64_t key) | |
425 | { | |
426 | int r; | |
427 | size_t size; | |
428 | unsigned nr_left, nr_right; | |
429 | struct dm_block *left, *right, *parent; | |
550929fa | 430 | struct btree_node *ln, *rn, *pn; |
3241b1d3 JT |
431 | __le64 location; |
432 | ||
433 | left = shadow_current(s); | |
434 | ||
435 | r = new_block(s->info, &right); | |
436 | if (r < 0) | |
437 | return r; | |
438 | ||
439 | ln = dm_block_data(left); | |
440 | rn = dm_block_data(right); | |
441 | ||
442 | nr_left = le32_to_cpu(ln->header.nr_entries) / 2; | |
443 | nr_right = le32_to_cpu(ln->header.nr_entries) - nr_left; | |
444 | ||
445 | ln->header.nr_entries = cpu_to_le32(nr_left); | |
446 | ||
447 | rn->header.flags = ln->header.flags; | |
448 | rn->header.nr_entries = cpu_to_le32(nr_right); | |
449 | rn->header.max_entries = ln->header.max_entries; | |
450 | rn->header.value_size = ln->header.value_size; | |
451 | memcpy(rn->keys, ln->keys + nr_left, nr_right * sizeof(rn->keys[0])); | |
452 | ||
453 | size = le32_to_cpu(ln->header.flags) & INTERNAL_NODE ? | |
454 | sizeof(uint64_t) : s->info->value_type.size; | |
a3aefb39 | 455 | memcpy(value_ptr(rn, 0), value_ptr(ln, nr_left), |
3241b1d3 JT |
456 | size * nr_right); |
457 | ||
458 | /* | |
459 | * Patch up the parent | |
460 | */ | |
461 | parent = shadow_parent(s); | |
462 | ||
463 | pn = dm_block_data(parent); | |
464 | location = cpu_to_le64(dm_block_location(left)); | |
465 | __dm_bless_for_disk(&location); | |
a3aefb39 | 466 | memcpy_disk(value_ptr(pn, parent_index), |
3241b1d3 JT |
467 | &location, sizeof(__le64)); |
468 | ||
469 | location = cpu_to_le64(dm_block_location(right)); | |
470 | __dm_bless_for_disk(&location); | |
471 | ||
472 | r = insert_at(sizeof(__le64), pn, parent_index + 1, | |
473 | le64_to_cpu(rn->keys[0]), &location); | |
474 | if (r) | |
475 | return r; | |
476 | ||
477 | if (key < le64_to_cpu(rn->keys[0])) { | |
478 | unlock_block(s->info, right); | |
479 | s->nodes[1] = left; | |
480 | } else { | |
481 | unlock_block(s->info, left); | |
482 | s->nodes[1] = right; | |
483 | } | |
484 | ||
485 | return 0; | |
486 | } | |
487 | ||
488 | /* | |
489 | * Splits a node by creating two new children beneath the given node. | |
490 | * | |
491 | * Before: | |
492 | * +----------+ | |
493 | * | A ++++++ | | |
494 | * +----------+ | |
495 | * | |
496 | * | |
497 | * After: | |
498 | * +------------+ | |
499 | * | A (shadow) | | |
500 | * +------------+ | |
501 | * | | | |
502 | * +------+ +----+ | |
503 | * | | | |
504 | * v v | |
505 | * +-------+ +-------+ | |
506 | * | B +++ | | C +++ | | |
507 | * +-------+ +-------+ | |
508 | */ | |
509 | static int btree_split_beneath(struct shadow_spine *s, uint64_t key) | |
510 | { | |
511 | int r; | |
512 | size_t size; | |
513 | unsigned nr_left, nr_right; | |
514 | struct dm_block *left, *right, *new_parent; | |
550929fa | 515 | struct btree_node *pn, *ln, *rn; |
3241b1d3 JT |
516 | __le64 val; |
517 | ||
518 | new_parent = shadow_current(s); | |
519 | ||
520 | r = new_block(s->info, &left); | |
521 | if (r < 0) | |
522 | return r; | |
523 | ||
524 | r = new_block(s->info, &right); | |
525 | if (r < 0) { | |
526 | /* FIXME: put left */ | |
527 | return r; | |
528 | } | |
529 | ||
530 | pn = dm_block_data(new_parent); | |
531 | ln = dm_block_data(left); | |
532 | rn = dm_block_data(right); | |
533 | ||
534 | nr_left = le32_to_cpu(pn->header.nr_entries) / 2; | |
535 | nr_right = le32_to_cpu(pn->header.nr_entries) - nr_left; | |
536 | ||
537 | ln->header.flags = pn->header.flags; | |
538 | ln->header.nr_entries = cpu_to_le32(nr_left); | |
539 | ln->header.max_entries = pn->header.max_entries; | |
540 | ln->header.value_size = pn->header.value_size; | |
541 | ||
542 | rn->header.flags = pn->header.flags; | |
543 | rn->header.nr_entries = cpu_to_le32(nr_right); | |
544 | rn->header.max_entries = pn->header.max_entries; | |
545 | rn->header.value_size = pn->header.value_size; | |
546 | ||
547 | memcpy(ln->keys, pn->keys, nr_left * sizeof(pn->keys[0])); | |
548 | memcpy(rn->keys, pn->keys + nr_left, nr_right * sizeof(pn->keys[0])); | |
549 | ||
550 | size = le32_to_cpu(pn->header.flags) & INTERNAL_NODE ? | |
551 | sizeof(__le64) : s->info->value_type.size; | |
a3aefb39 JT |
552 | memcpy(value_ptr(ln, 0), value_ptr(pn, 0), nr_left * size); |
553 | memcpy(value_ptr(rn, 0), value_ptr(pn, nr_left), | |
3241b1d3 JT |
554 | nr_right * size); |
555 | ||
556 | /* new_parent should just point to l and r now */ | |
557 | pn->header.flags = cpu_to_le32(INTERNAL_NODE); | |
558 | pn->header.nr_entries = cpu_to_le32(2); | |
559 | pn->header.max_entries = cpu_to_le32( | |
560 | calc_max_entries(sizeof(__le64), | |
561 | dm_bm_block_size( | |
562 | dm_tm_get_bm(s->info->tm)))); | |
563 | pn->header.value_size = cpu_to_le32(sizeof(__le64)); | |
564 | ||
565 | val = cpu_to_le64(dm_block_location(left)); | |
566 | __dm_bless_for_disk(&val); | |
567 | pn->keys[0] = ln->keys[0]; | |
a3aefb39 | 568 | memcpy_disk(value_ptr(pn, 0), &val, sizeof(__le64)); |
3241b1d3 JT |
569 | |
570 | val = cpu_to_le64(dm_block_location(right)); | |
571 | __dm_bless_for_disk(&val); | |
572 | pn->keys[1] = rn->keys[0]; | |
a3aefb39 | 573 | memcpy_disk(value_ptr(pn, 1), &val, sizeof(__le64)); |
3241b1d3 JT |
574 | |
575 | /* | |
576 | * rejig the spine. This is ugly, since it knows too | |
577 | * much about the spine | |
578 | */ | |
579 | if (s->nodes[0] != new_parent) { | |
580 | unlock_block(s->info, s->nodes[0]); | |
581 | s->nodes[0] = new_parent; | |
582 | } | |
583 | if (key < le64_to_cpu(rn->keys[0])) { | |
584 | unlock_block(s->info, right); | |
585 | s->nodes[1] = left; | |
586 | } else { | |
587 | unlock_block(s->info, left); | |
588 | s->nodes[1] = right; | |
589 | } | |
590 | s->count = 2; | |
591 | ||
592 | return 0; | |
593 | } | |
594 | ||
595 | static int btree_insert_raw(struct shadow_spine *s, dm_block_t root, | |
596 | struct dm_btree_value_type *vt, | |
597 | uint64_t key, unsigned *index) | |
598 | { | |
599 | int r, i = *index, top = 1; | |
550929fa | 600 | struct btree_node *node; |
3241b1d3 JT |
601 | |
602 | for (;;) { | |
603 | r = shadow_step(s, root, vt); | |
604 | if (r < 0) | |
605 | return r; | |
606 | ||
607 | node = dm_block_data(shadow_current(s)); | |
608 | ||
609 | /* | |
610 | * We have to patch up the parent node, ugly, but I don't | |
611 | * see a way to do this automatically as part of the spine | |
612 | * op. | |
613 | */ | |
614 | if (shadow_has_parent(s) && i >= 0) { /* FIXME: second clause unness. */ | |
615 | __le64 location = cpu_to_le64(dm_block_location(shadow_current(s))); | |
616 | ||
617 | __dm_bless_for_disk(&location); | |
a3aefb39 | 618 | memcpy_disk(value_ptr(dm_block_data(shadow_parent(s)), i), |
3241b1d3 JT |
619 | &location, sizeof(__le64)); |
620 | } | |
621 | ||
622 | node = dm_block_data(shadow_current(s)); | |
623 | ||
624 | if (node->header.nr_entries == node->header.max_entries) { | |
625 | if (top) | |
626 | r = btree_split_beneath(s, key); | |
627 | else | |
628 | r = btree_split_sibling(s, root, i, key); | |
629 | ||
630 | if (r < 0) | |
631 | return r; | |
632 | } | |
633 | ||
634 | node = dm_block_data(shadow_current(s)); | |
635 | ||
636 | i = lower_bound(node, key); | |
637 | ||
638 | if (le32_to_cpu(node->header.flags) & LEAF_NODE) | |
639 | break; | |
640 | ||
641 | if (i < 0) { | |
642 | /* change the bounds on the lowest key */ | |
643 | node->keys[0] = cpu_to_le64(key); | |
644 | i = 0; | |
645 | } | |
646 | ||
647 | root = value64(node, i); | |
648 | top = 0; | |
649 | } | |
650 | ||
651 | if (i < 0 || le64_to_cpu(node->keys[i]) != key) | |
652 | i++; | |
653 | ||
654 | *index = i; | |
655 | return 0; | |
656 | } | |
657 | ||
658 | static int insert(struct dm_btree_info *info, dm_block_t root, | |
659 | uint64_t *keys, void *value, dm_block_t *new_root, | |
660 | int *inserted) | |
661 | __dm_written_to_disk(value) | |
662 | { | |
663 | int r, need_insert; | |
664 | unsigned level, index = -1, last_level = info->levels - 1; | |
665 | dm_block_t block = root; | |
666 | struct shadow_spine spine; | |
550929fa | 667 | struct btree_node *n; |
3241b1d3 JT |
668 | struct dm_btree_value_type le64_type; |
669 | ||
b0dc3c8b | 670 | init_le64_type(info->tm, &le64_type); |
3241b1d3 JT |
671 | init_shadow_spine(&spine, info); |
672 | ||
673 | for (level = 0; level < (info->levels - 1); level++) { | |
674 | r = btree_insert_raw(&spine, block, &le64_type, keys[level], &index); | |
675 | if (r < 0) | |
676 | goto bad; | |
677 | ||
678 | n = dm_block_data(shadow_current(&spine)); | |
679 | need_insert = ((index >= le32_to_cpu(n->header.nr_entries)) || | |
680 | (le64_to_cpu(n->keys[index]) != keys[level])); | |
681 | ||
682 | if (need_insert) { | |
683 | dm_block_t new_tree; | |
684 | __le64 new_le; | |
685 | ||
686 | r = dm_btree_empty(info, &new_tree); | |
687 | if (r < 0) | |
688 | goto bad; | |
689 | ||
690 | new_le = cpu_to_le64(new_tree); | |
691 | __dm_bless_for_disk(&new_le); | |
692 | ||
693 | r = insert_at(sizeof(uint64_t), n, index, | |
694 | keys[level], &new_le); | |
695 | if (r) | |
696 | goto bad; | |
697 | } | |
698 | ||
699 | if (level < last_level) | |
700 | block = value64(n, index); | |
701 | } | |
702 | ||
703 | r = btree_insert_raw(&spine, block, &info->value_type, | |
704 | keys[level], &index); | |
705 | if (r < 0) | |
706 | goto bad; | |
707 | ||
708 | n = dm_block_data(shadow_current(&spine)); | |
709 | need_insert = ((index >= le32_to_cpu(n->header.nr_entries)) || | |
710 | (le64_to_cpu(n->keys[index]) != keys[level])); | |
711 | ||
712 | if (need_insert) { | |
713 | if (inserted) | |
714 | *inserted = 1; | |
715 | ||
716 | r = insert_at(info->value_type.size, n, index, | |
717 | keys[level], value); | |
718 | if (r) | |
719 | goto bad_unblessed; | |
720 | } else { | |
721 | if (inserted) | |
722 | *inserted = 0; | |
723 | ||
724 | if (info->value_type.dec && | |
725 | (!info->value_type.equal || | |
726 | !info->value_type.equal( | |
727 | info->value_type.context, | |
a3aefb39 | 728 | value_ptr(n, index), |
3241b1d3 JT |
729 | value))) { |
730 | info->value_type.dec(info->value_type.context, | |
a3aefb39 | 731 | value_ptr(n, index)); |
3241b1d3 | 732 | } |
a3aefb39 | 733 | memcpy_disk(value_ptr(n, index), |
3241b1d3 JT |
734 | value, info->value_type.size); |
735 | } | |
736 | ||
737 | *new_root = shadow_root(&spine); | |
738 | exit_shadow_spine(&spine); | |
739 | ||
740 | return 0; | |
741 | ||
742 | bad: | |
743 | __dm_unbless_for_disk(value); | |
744 | bad_unblessed: | |
745 | exit_shadow_spine(&spine); | |
746 | return r; | |
747 | } | |
748 | ||
749 | int dm_btree_insert(struct dm_btree_info *info, dm_block_t root, | |
750 | uint64_t *keys, void *value, dm_block_t *new_root) | |
751 | __dm_written_to_disk(value) | |
752 | { | |
753 | return insert(info, root, keys, value, new_root, NULL); | |
754 | } | |
755 | EXPORT_SYMBOL_GPL(dm_btree_insert); | |
756 | ||
757 | int dm_btree_insert_notify(struct dm_btree_info *info, dm_block_t root, | |
758 | uint64_t *keys, void *value, dm_block_t *new_root, | |
759 | int *inserted) | |
760 | __dm_written_to_disk(value) | |
761 | { | |
762 | return insert(info, root, keys, value, new_root, inserted); | |
763 | } | |
764 | EXPORT_SYMBOL_GPL(dm_btree_insert_notify); | |
765 | ||
766 | /*----------------------------------------------------------------*/ | |
767 | ||
f164e690 JT |
768 | static int find_key(struct ro_spine *s, dm_block_t block, bool find_highest, |
769 | uint64_t *result_key, dm_block_t *next_block) | |
3241b1d3 JT |
770 | { |
771 | int i, r; | |
772 | uint32_t flags; | |
773 | ||
774 | do { | |
775 | r = ro_step(s, block); | |
776 | if (r < 0) | |
777 | return r; | |
778 | ||
779 | flags = le32_to_cpu(ro_node(s)->header.flags); | |
780 | i = le32_to_cpu(ro_node(s)->header.nr_entries); | |
781 | if (!i) | |
782 | return -ENODATA; | |
783 | else | |
784 | i--; | |
785 | ||
f164e690 JT |
786 | if (find_highest) |
787 | *result_key = le64_to_cpu(ro_node(s)->keys[i]); | |
788 | else | |
789 | *result_key = le64_to_cpu(ro_node(s)->keys[0]); | |
790 | ||
3241b1d3 JT |
791 | if (next_block || flags & INTERNAL_NODE) |
792 | block = value64(ro_node(s), i); | |
793 | ||
794 | } while (flags & INTERNAL_NODE); | |
795 | ||
796 | if (next_block) | |
797 | *next_block = block; | |
798 | return 0; | |
799 | } | |
800 | ||
f164e690 JT |
801 | static int dm_btree_find_key(struct dm_btree_info *info, dm_block_t root, |
802 | bool find_highest, uint64_t *result_keys) | |
3241b1d3 JT |
803 | { |
804 | int r = 0, count = 0, level; | |
805 | struct ro_spine spine; | |
806 | ||
807 | init_ro_spine(&spine, info); | |
808 | for (level = 0; level < info->levels; level++) { | |
f164e690 JT |
809 | r = find_key(&spine, root, find_highest, result_keys + level, |
810 | level == info->levels - 1 ? NULL : &root); | |
3241b1d3 JT |
811 | if (r == -ENODATA) { |
812 | r = 0; | |
813 | break; | |
814 | ||
815 | } else if (r) | |
816 | break; | |
817 | ||
818 | count++; | |
819 | } | |
820 | exit_ro_spine(&spine); | |
821 | ||
822 | return r ? r : count; | |
823 | } | |
f164e690 JT |
824 | |
825 | int dm_btree_find_highest_key(struct dm_btree_info *info, dm_block_t root, | |
826 | uint64_t *result_keys) | |
827 | { | |
828 | return dm_btree_find_key(info, root, true, result_keys); | |
829 | } | |
3241b1d3 | 830 | EXPORT_SYMBOL_GPL(dm_btree_find_highest_key); |
4e7f1f90 | 831 | |
f164e690 JT |
832 | int dm_btree_find_lowest_key(struct dm_btree_info *info, dm_block_t root, |
833 | uint64_t *result_keys) | |
834 | { | |
835 | return dm_btree_find_key(info, root, false, result_keys); | |
836 | } | |
837 | EXPORT_SYMBOL_GPL(dm_btree_find_lowest_key); | |
838 | ||
839 | /*----------------------------------------------------------------*/ | |
840 | ||
4e7f1f90 JT |
841 | /* |
842 | * FIXME: We shouldn't use a recursive algorithm when we have limited stack | |
843 | * space. Also this only works for single level trees. | |
844 | */ | |
9b460d36 | 845 | static int walk_node(struct dm_btree_info *info, dm_block_t block, |
4e7f1f90 JT |
846 | int (*fn)(void *context, uint64_t *keys, void *leaf), |
847 | void *context) | |
848 | { | |
849 | int r; | |
850 | unsigned i, nr; | |
9b460d36 | 851 | struct dm_block *node; |
4e7f1f90 JT |
852 | struct btree_node *n; |
853 | uint64_t keys; | |
854 | ||
9b460d36 JT |
855 | r = bn_read_lock(info, block, &node); |
856 | if (r) | |
857 | return r; | |
858 | ||
859 | n = dm_block_data(node); | |
4e7f1f90 JT |
860 | |
861 | nr = le32_to_cpu(n->header.nr_entries); | |
862 | for (i = 0; i < nr; i++) { | |
863 | if (le32_to_cpu(n->header.flags) & INTERNAL_NODE) { | |
9b460d36 | 864 | r = walk_node(info, value64(n, i), fn, context); |
4e7f1f90 JT |
865 | if (r) |
866 | goto out; | |
867 | } else { | |
868 | keys = le64_to_cpu(*key_ptr(n, i)); | |
869 | r = fn(context, &keys, value_ptr(n, i)); | |
870 | if (r) | |
871 | goto out; | |
872 | } | |
873 | } | |
874 | ||
875 | out: | |
9b460d36 | 876 | dm_tm_unlock(info->tm, node); |
4e7f1f90 JT |
877 | return r; |
878 | } | |
879 | ||
880 | int dm_btree_walk(struct dm_btree_info *info, dm_block_t root, | |
881 | int (*fn)(void *context, uint64_t *keys, void *leaf), | |
882 | void *context) | |
883 | { | |
4e7f1f90 | 884 | BUG_ON(info->levels > 1); |
9b460d36 | 885 | return walk_node(info, root, fn, context); |
4e7f1f90 JT |
886 | } |
887 | EXPORT_SYMBOL_GPL(dm_btree_walk); |