Commit | Line | Data |
---|---|---|
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); | |
4c7da06f MP |
144 | unlock_block(info, b); |
145 | ||
146 | return 0; | |
3241b1d3 JT |
147 | } |
148 | EXPORT_SYMBOL_GPL(dm_btree_empty); | |
149 | ||
150 | /*----------------------------------------------------------------*/ | |
151 | ||
152 | /* | |
153 | * Deletion uses a recursive algorithm, since we have limited stack space | |
154 | * we explicitly manage our own stack on the heap. | |
155 | */ | |
156 | #define MAX_SPINE_DEPTH 64 | |
157 | struct frame { | |
158 | struct dm_block *b; | |
550929fa | 159 | struct btree_node *n; |
3241b1d3 JT |
160 | unsigned level; |
161 | unsigned nr_children; | |
162 | unsigned current_child; | |
163 | }; | |
164 | ||
165 | struct del_stack { | |
04f17c80 | 166 | struct dm_btree_info *info; |
3241b1d3 JT |
167 | struct dm_transaction_manager *tm; |
168 | int top; | |
169 | struct frame spine[MAX_SPINE_DEPTH]; | |
170 | }; | |
171 | ||
172 | static int top_frame(struct del_stack *s, struct frame **f) | |
173 | { | |
174 | if (s->top < 0) { | |
175 | DMERR("btree deletion stack empty"); | |
176 | return -EINVAL; | |
177 | } | |
178 | ||
179 | *f = s->spine + s->top; | |
180 | ||
181 | return 0; | |
182 | } | |
183 | ||
184 | static int unprocessed_frames(struct del_stack *s) | |
185 | { | |
186 | return s->top >= 0; | |
187 | } | |
188 | ||
04f17c80 JT |
189 | static void prefetch_children(struct del_stack *s, struct frame *f) |
190 | { | |
191 | unsigned i; | |
192 | struct dm_block_manager *bm = dm_tm_get_bm(s->tm); | |
193 | ||
194 | for (i = 0; i < f->nr_children; i++) | |
195 | dm_bm_prefetch(bm, value64(f->n, i)); | |
196 | } | |
197 | ||
198 | static bool is_internal_level(struct dm_btree_info *info, struct frame *f) | |
199 | { | |
200 | return f->level < (info->levels - 1); | |
201 | } | |
202 | ||
3241b1d3 JT |
203 | static int push_frame(struct del_stack *s, dm_block_t b, unsigned level) |
204 | { | |
205 | int r; | |
206 | uint32_t ref_count; | |
207 | ||
208 | if (s->top >= MAX_SPINE_DEPTH - 1) { | |
209 | DMERR("btree deletion stack out of memory"); | |
210 | return -ENOMEM; | |
211 | } | |
212 | ||
213 | r = dm_tm_ref(s->tm, b, &ref_count); | |
214 | if (r) | |
215 | return r; | |
216 | ||
217 | if (ref_count > 1) | |
218 | /* | |
219 | * This is a shared node, so we can just decrement it's | |
220 | * reference counter and leave the children. | |
221 | */ | |
222 | dm_tm_dec(s->tm, b); | |
223 | ||
224 | else { | |
04f17c80 | 225 | uint32_t flags; |
3241b1d3 JT |
226 | struct frame *f = s->spine + ++s->top; |
227 | ||
228 | r = dm_tm_read_lock(s->tm, b, &btree_node_validator, &f->b); | |
229 | if (r) { | |
230 | s->top--; | |
231 | return r; | |
232 | } | |
233 | ||
234 | f->n = dm_block_data(f->b); | |
235 | f->level = level; | |
236 | f->nr_children = le32_to_cpu(f->n->header.nr_entries); | |
237 | f->current_child = 0; | |
04f17c80 JT |
238 | |
239 | flags = le32_to_cpu(f->n->header.flags); | |
240 | if (flags & INTERNAL_NODE || is_internal_level(s->info, f)) | |
241 | prefetch_children(s, f); | |
3241b1d3 JT |
242 | } |
243 | ||
244 | return 0; | |
245 | } | |
246 | ||
247 | static void pop_frame(struct del_stack *s) | |
248 | { | |
249 | struct frame *f = s->spine + s->top--; | |
250 | ||
251 | dm_tm_dec(s->tm, dm_block_location(f->b)); | |
252 | dm_tm_unlock(s->tm, f->b); | |
253 | } | |
254 | ||
255 | int dm_btree_del(struct dm_btree_info *info, dm_block_t root) | |
256 | { | |
257 | int r; | |
258 | struct del_stack *s; | |
259 | ||
1c751879 | 260 | s = kmalloc(sizeof(*s), GFP_NOIO); |
3241b1d3 JT |
261 | if (!s) |
262 | return -ENOMEM; | |
04f17c80 | 263 | s->info = info; |
3241b1d3 JT |
264 | s->tm = info->tm; |
265 | s->top = -1; | |
266 | ||
e3cbf945 | 267 | r = push_frame(s, root, 0); |
3241b1d3 JT |
268 | if (r) |
269 | goto out; | |
270 | ||
271 | while (unprocessed_frames(s)) { | |
272 | uint32_t flags; | |
273 | struct frame *f; | |
274 | dm_block_t b; | |
275 | ||
276 | r = top_frame(s, &f); | |
277 | if (r) | |
278 | goto out; | |
279 | ||
280 | if (f->current_child >= f->nr_children) { | |
281 | pop_frame(s); | |
282 | continue; | |
283 | } | |
284 | ||
285 | flags = le32_to_cpu(f->n->header.flags); | |
286 | if (flags & INTERNAL_NODE) { | |
287 | b = value64(f->n, f->current_child); | |
288 | f->current_child++; | |
289 | r = push_frame(s, b, f->level); | |
290 | if (r) | |
291 | goto out; | |
292 | ||
e3cbf945 | 293 | } else if (is_internal_level(info, f)) { |
3241b1d3 JT |
294 | b = value64(f->n, f->current_child); |
295 | f->current_child++; | |
296 | r = push_frame(s, b, f->level + 1); | |
297 | if (r) | |
298 | goto out; | |
299 | ||
300 | } else { | |
301 | if (info->value_type.dec) { | |
302 | unsigned i; | |
303 | ||
304 | for (i = 0; i < f->nr_children; i++) | |
305 | info->value_type.dec(info->value_type.context, | |
a3aefb39 | 306 | value_ptr(f->n, i)); |
3241b1d3 | 307 | } |
cd5acf0b | 308 | pop_frame(s); |
3241b1d3 JT |
309 | } |
310 | } | |
311 | ||
312 | out: | |
313 | kfree(s); | |
314 | return r; | |
315 | } | |
316 | EXPORT_SYMBOL_GPL(dm_btree_del); | |
317 | ||
318 | /*----------------------------------------------------------------*/ | |
319 | ||
320 | static int btree_lookup_raw(struct ro_spine *s, dm_block_t block, uint64_t key, | |
550929fa | 321 | int (*search_fn)(struct btree_node *, uint64_t), |
3241b1d3 JT |
322 | uint64_t *result_key, void *v, size_t value_size) |
323 | { | |
324 | int i, r; | |
325 | uint32_t flags, nr_entries; | |
326 | ||
327 | do { | |
328 | r = ro_step(s, block); | |
329 | if (r < 0) | |
330 | return r; | |
331 | ||
332 | i = search_fn(ro_node(s), key); | |
333 | ||
334 | flags = le32_to_cpu(ro_node(s)->header.flags); | |
335 | nr_entries = le32_to_cpu(ro_node(s)->header.nr_entries); | |
336 | if (i < 0 || i >= nr_entries) | |
337 | return -ENODATA; | |
338 | ||
339 | if (flags & INTERNAL_NODE) | |
340 | block = value64(ro_node(s), i); | |
341 | ||
342 | } while (!(flags & LEAF_NODE)); | |
343 | ||
344 | *result_key = le64_to_cpu(ro_node(s)->keys[i]); | |
a3aefb39 | 345 | memcpy(v, value_ptr(ro_node(s), i), value_size); |
3241b1d3 JT |
346 | |
347 | return 0; | |
348 | } | |
349 | ||
350 | int dm_btree_lookup(struct dm_btree_info *info, dm_block_t root, | |
351 | uint64_t *keys, void *value_le) | |
352 | { | |
353 | unsigned level, last_level = info->levels - 1; | |
354 | int r = -ENODATA; | |
355 | uint64_t rkey; | |
356 | __le64 internal_value_le; | |
357 | struct ro_spine spine; | |
358 | ||
359 | init_ro_spine(&spine, info); | |
360 | for (level = 0; level < info->levels; level++) { | |
361 | size_t size; | |
362 | void *value_p; | |
363 | ||
364 | if (level == last_level) { | |
365 | value_p = value_le; | |
366 | size = info->value_type.size; | |
367 | ||
368 | } else { | |
369 | value_p = &internal_value_le; | |
370 | size = sizeof(uint64_t); | |
371 | } | |
372 | ||
373 | r = btree_lookup_raw(&spine, root, keys[level], | |
374 | lower_bound, &rkey, | |
375 | value_p, size); | |
376 | ||
377 | if (!r) { | |
378 | if (rkey != keys[level]) { | |
379 | exit_ro_spine(&spine); | |
380 | return -ENODATA; | |
381 | } | |
382 | } else { | |
383 | exit_ro_spine(&spine); | |
384 | return r; | |
385 | } | |
386 | ||
387 | root = le64_to_cpu(internal_value_le); | |
388 | } | |
389 | exit_ro_spine(&spine); | |
390 | ||
391 | return r; | |
392 | } | |
393 | EXPORT_SYMBOL_GPL(dm_btree_lookup); | |
394 | ||
395 | /* | |
396 | * Splits a node by creating a sibling node and shifting half the nodes | |
397 | * contents across. Assumes there is a parent node, and it has room for | |
398 | * another child. | |
399 | * | |
400 | * Before: | |
401 | * +--------+ | |
402 | * | Parent | | |
403 | * +--------+ | |
404 | * | | |
405 | * v | |
406 | * +----------+ | |
407 | * | A ++++++ | | |
408 | * +----------+ | |
409 | * | |
410 | * | |
411 | * After: | |
412 | * +--------+ | |
413 | * | Parent | | |
414 | * +--------+ | |
415 | * | | | |
416 | * v +------+ | |
417 | * +---------+ | | |
418 | * | A* +++ | v | |
419 | * +---------+ +-------+ | |
420 | * | B +++ | | |
421 | * +-------+ | |
422 | * | |
423 | * Where A* is a shadow of A. | |
424 | */ | |
0a8d4c3e VG |
425 | static int btree_split_sibling(struct shadow_spine *s, unsigned parent_index, |
426 | uint64_t key) | |
3241b1d3 JT |
427 | { |
428 | int r; | |
429 | size_t size; | |
430 | unsigned nr_left, nr_right; | |
431 | struct dm_block *left, *right, *parent; | |
550929fa | 432 | struct btree_node *ln, *rn, *pn; |
3241b1d3 JT |
433 | __le64 location; |
434 | ||
435 | left = shadow_current(s); | |
436 | ||
437 | r = new_block(s->info, &right); | |
438 | if (r < 0) | |
439 | return r; | |
440 | ||
441 | ln = dm_block_data(left); | |
442 | rn = dm_block_data(right); | |
443 | ||
444 | nr_left = le32_to_cpu(ln->header.nr_entries) / 2; | |
445 | nr_right = le32_to_cpu(ln->header.nr_entries) - nr_left; | |
446 | ||
447 | ln->header.nr_entries = cpu_to_le32(nr_left); | |
448 | ||
449 | rn->header.flags = ln->header.flags; | |
450 | rn->header.nr_entries = cpu_to_le32(nr_right); | |
451 | rn->header.max_entries = ln->header.max_entries; | |
452 | rn->header.value_size = ln->header.value_size; | |
453 | memcpy(rn->keys, ln->keys + nr_left, nr_right * sizeof(rn->keys[0])); | |
454 | ||
455 | size = le32_to_cpu(ln->header.flags) & INTERNAL_NODE ? | |
456 | sizeof(uint64_t) : s->info->value_type.size; | |
a3aefb39 | 457 | memcpy(value_ptr(rn, 0), value_ptr(ln, nr_left), |
3241b1d3 JT |
458 | size * nr_right); |
459 | ||
460 | /* | |
461 | * Patch up the parent | |
462 | */ | |
463 | parent = shadow_parent(s); | |
464 | ||
465 | pn = dm_block_data(parent); | |
466 | location = cpu_to_le64(dm_block_location(left)); | |
467 | __dm_bless_for_disk(&location); | |
a3aefb39 | 468 | memcpy_disk(value_ptr(pn, parent_index), |
3241b1d3 JT |
469 | &location, sizeof(__le64)); |
470 | ||
471 | location = cpu_to_le64(dm_block_location(right)); | |
472 | __dm_bless_for_disk(&location); | |
473 | ||
474 | r = insert_at(sizeof(__le64), pn, parent_index + 1, | |
475 | le64_to_cpu(rn->keys[0]), &location); | |
476 | if (r) | |
477 | return r; | |
478 | ||
479 | if (key < le64_to_cpu(rn->keys[0])) { | |
480 | unlock_block(s->info, right); | |
481 | s->nodes[1] = left; | |
482 | } else { | |
483 | unlock_block(s->info, left); | |
484 | s->nodes[1] = right; | |
485 | } | |
486 | ||
487 | return 0; | |
488 | } | |
489 | ||
490 | /* | |
491 | * Splits a node by creating two new children beneath the given node. | |
492 | * | |
493 | * Before: | |
494 | * +----------+ | |
495 | * | A ++++++ | | |
496 | * +----------+ | |
497 | * | |
498 | * | |
499 | * After: | |
500 | * +------------+ | |
501 | * | A (shadow) | | |
502 | * +------------+ | |
503 | * | | | |
504 | * +------+ +----+ | |
505 | * | | | |
506 | * v v | |
507 | * +-------+ +-------+ | |
508 | * | B +++ | | C +++ | | |
509 | * +-------+ +-------+ | |
510 | */ | |
511 | static int btree_split_beneath(struct shadow_spine *s, uint64_t key) | |
512 | { | |
513 | int r; | |
514 | size_t size; | |
515 | unsigned nr_left, nr_right; | |
516 | struct dm_block *left, *right, *new_parent; | |
550929fa | 517 | struct btree_node *pn, *ln, *rn; |
3241b1d3 JT |
518 | __le64 val; |
519 | ||
520 | new_parent = shadow_current(s); | |
521 | ||
522 | r = new_block(s->info, &left); | |
523 | if (r < 0) | |
524 | return r; | |
525 | ||
526 | r = new_block(s->info, &right); | |
527 | if (r < 0) { | |
528 | /* FIXME: put left */ | |
529 | return r; | |
530 | } | |
531 | ||
532 | pn = dm_block_data(new_parent); | |
533 | ln = dm_block_data(left); | |
534 | rn = dm_block_data(right); | |
535 | ||
536 | nr_left = le32_to_cpu(pn->header.nr_entries) / 2; | |
537 | nr_right = le32_to_cpu(pn->header.nr_entries) - nr_left; | |
538 | ||
539 | ln->header.flags = pn->header.flags; | |
540 | ln->header.nr_entries = cpu_to_le32(nr_left); | |
541 | ln->header.max_entries = pn->header.max_entries; | |
542 | ln->header.value_size = pn->header.value_size; | |
543 | ||
544 | rn->header.flags = pn->header.flags; | |
545 | rn->header.nr_entries = cpu_to_le32(nr_right); | |
546 | rn->header.max_entries = pn->header.max_entries; | |
547 | rn->header.value_size = pn->header.value_size; | |
548 | ||
549 | memcpy(ln->keys, pn->keys, nr_left * sizeof(pn->keys[0])); | |
550 | memcpy(rn->keys, pn->keys + nr_left, nr_right * sizeof(pn->keys[0])); | |
551 | ||
552 | size = le32_to_cpu(pn->header.flags) & INTERNAL_NODE ? | |
553 | sizeof(__le64) : s->info->value_type.size; | |
a3aefb39 JT |
554 | memcpy(value_ptr(ln, 0), value_ptr(pn, 0), nr_left * size); |
555 | memcpy(value_ptr(rn, 0), value_ptr(pn, nr_left), | |
3241b1d3 JT |
556 | nr_right * size); |
557 | ||
558 | /* new_parent should just point to l and r now */ | |
559 | pn->header.flags = cpu_to_le32(INTERNAL_NODE); | |
560 | pn->header.nr_entries = cpu_to_le32(2); | |
561 | pn->header.max_entries = cpu_to_le32( | |
562 | calc_max_entries(sizeof(__le64), | |
563 | dm_bm_block_size( | |
564 | dm_tm_get_bm(s->info->tm)))); | |
565 | pn->header.value_size = cpu_to_le32(sizeof(__le64)); | |
566 | ||
567 | val = cpu_to_le64(dm_block_location(left)); | |
568 | __dm_bless_for_disk(&val); | |
569 | pn->keys[0] = ln->keys[0]; | |
a3aefb39 | 570 | memcpy_disk(value_ptr(pn, 0), &val, sizeof(__le64)); |
3241b1d3 JT |
571 | |
572 | val = cpu_to_le64(dm_block_location(right)); | |
573 | __dm_bless_for_disk(&val); | |
574 | pn->keys[1] = rn->keys[0]; | |
a3aefb39 | 575 | memcpy_disk(value_ptr(pn, 1), &val, sizeof(__le64)); |
3241b1d3 JT |
576 | |
577 | /* | |
578 | * rejig the spine. This is ugly, since it knows too | |
579 | * much about the spine | |
580 | */ | |
581 | if (s->nodes[0] != new_parent) { | |
582 | unlock_block(s->info, s->nodes[0]); | |
583 | s->nodes[0] = new_parent; | |
584 | } | |
585 | if (key < le64_to_cpu(rn->keys[0])) { | |
586 | unlock_block(s->info, right); | |
587 | s->nodes[1] = left; | |
588 | } else { | |
589 | unlock_block(s->info, left); | |
590 | s->nodes[1] = right; | |
591 | } | |
592 | s->count = 2; | |
593 | ||
594 | return 0; | |
595 | } | |
596 | ||
597 | static int btree_insert_raw(struct shadow_spine *s, dm_block_t root, | |
598 | struct dm_btree_value_type *vt, | |
599 | uint64_t key, unsigned *index) | |
600 | { | |
601 | int r, i = *index, top = 1; | |
550929fa | 602 | struct btree_node *node; |
3241b1d3 JT |
603 | |
604 | for (;;) { | |
605 | r = shadow_step(s, root, vt); | |
606 | if (r < 0) | |
607 | return r; | |
608 | ||
609 | node = dm_block_data(shadow_current(s)); | |
610 | ||
611 | /* | |
612 | * We have to patch up the parent node, ugly, but I don't | |
613 | * see a way to do this automatically as part of the spine | |
614 | * op. | |
615 | */ | |
616 | if (shadow_has_parent(s) && i >= 0) { /* FIXME: second clause unness. */ | |
617 | __le64 location = cpu_to_le64(dm_block_location(shadow_current(s))); | |
618 | ||
619 | __dm_bless_for_disk(&location); | |
a3aefb39 | 620 | memcpy_disk(value_ptr(dm_block_data(shadow_parent(s)), i), |
3241b1d3 JT |
621 | &location, sizeof(__le64)); |
622 | } | |
623 | ||
624 | node = dm_block_data(shadow_current(s)); | |
625 | ||
626 | if (node->header.nr_entries == node->header.max_entries) { | |
627 | if (top) | |
628 | r = btree_split_beneath(s, key); | |
629 | else | |
0a8d4c3e | 630 | r = btree_split_sibling(s, i, key); |
3241b1d3 JT |
631 | |
632 | if (r < 0) | |
633 | return r; | |
634 | } | |
635 | ||
636 | node = dm_block_data(shadow_current(s)); | |
637 | ||
638 | i = lower_bound(node, key); | |
639 | ||
640 | if (le32_to_cpu(node->header.flags) & LEAF_NODE) | |
641 | break; | |
642 | ||
643 | if (i < 0) { | |
644 | /* change the bounds on the lowest key */ | |
645 | node->keys[0] = cpu_to_le64(key); | |
646 | i = 0; | |
647 | } | |
648 | ||
649 | root = value64(node, i); | |
650 | top = 0; | |
651 | } | |
652 | ||
653 | if (i < 0 || le64_to_cpu(node->keys[i]) != key) | |
654 | i++; | |
655 | ||
656 | *index = i; | |
657 | return 0; | |
658 | } | |
659 | ||
660 | static int insert(struct dm_btree_info *info, dm_block_t root, | |
661 | uint64_t *keys, void *value, dm_block_t *new_root, | |
662 | int *inserted) | |
663 | __dm_written_to_disk(value) | |
664 | { | |
665 | int r, need_insert; | |
666 | unsigned level, index = -1, last_level = info->levels - 1; | |
667 | dm_block_t block = root; | |
668 | struct shadow_spine spine; | |
550929fa | 669 | struct btree_node *n; |
3241b1d3 JT |
670 | struct dm_btree_value_type le64_type; |
671 | ||
b0dc3c8b | 672 | init_le64_type(info->tm, &le64_type); |
3241b1d3 JT |
673 | init_shadow_spine(&spine, info); |
674 | ||
675 | for (level = 0; level < (info->levels - 1); level++) { | |
676 | r = btree_insert_raw(&spine, block, &le64_type, keys[level], &index); | |
677 | if (r < 0) | |
678 | goto bad; | |
679 | ||
680 | n = dm_block_data(shadow_current(&spine)); | |
681 | need_insert = ((index >= le32_to_cpu(n->header.nr_entries)) || | |
682 | (le64_to_cpu(n->keys[index]) != keys[level])); | |
683 | ||
684 | if (need_insert) { | |
685 | dm_block_t new_tree; | |
686 | __le64 new_le; | |
687 | ||
688 | r = dm_btree_empty(info, &new_tree); | |
689 | if (r < 0) | |
690 | goto bad; | |
691 | ||
692 | new_le = cpu_to_le64(new_tree); | |
693 | __dm_bless_for_disk(&new_le); | |
694 | ||
695 | r = insert_at(sizeof(uint64_t), n, index, | |
696 | keys[level], &new_le); | |
697 | if (r) | |
698 | goto bad; | |
699 | } | |
700 | ||
701 | if (level < last_level) | |
702 | block = value64(n, index); | |
703 | } | |
704 | ||
705 | r = btree_insert_raw(&spine, block, &info->value_type, | |
706 | keys[level], &index); | |
707 | if (r < 0) | |
708 | goto bad; | |
709 | ||
710 | n = dm_block_data(shadow_current(&spine)); | |
711 | need_insert = ((index >= le32_to_cpu(n->header.nr_entries)) || | |
712 | (le64_to_cpu(n->keys[index]) != keys[level])); | |
713 | ||
714 | if (need_insert) { | |
715 | if (inserted) | |
716 | *inserted = 1; | |
717 | ||
718 | r = insert_at(info->value_type.size, n, index, | |
719 | keys[level], value); | |
720 | if (r) | |
721 | goto bad_unblessed; | |
722 | } else { | |
723 | if (inserted) | |
724 | *inserted = 0; | |
725 | ||
726 | if (info->value_type.dec && | |
727 | (!info->value_type.equal || | |
728 | !info->value_type.equal( | |
729 | info->value_type.context, | |
a3aefb39 | 730 | value_ptr(n, index), |
3241b1d3 JT |
731 | value))) { |
732 | info->value_type.dec(info->value_type.context, | |
a3aefb39 | 733 | value_ptr(n, index)); |
3241b1d3 | 734 | } |
a3aefb39 | 735 | memcpy_disk(value_ptr(n, index), |
3241b1d3 JT |
736 | value, info->value_type.size); |
737 | } | |
738 | ||
739 | *new_root = shadow_root(&spine); | |
740 | exit_shadow_spine(&spine); | |
741 | ||
742 | return 0; | |
743 | ||
744 | bad: | |
745 | __dm_unbless_for_disk(value); | |
746 | bad_unblessed: | |
747 | exit_shadow_spine(&spine); | |
748 | return r; | |
749 | } | |
750 | ||
751 | int dm_btree_insert(struct dm_btree_info *info, dm_block_t root, | |
752 | uint64_t *keys, void *value, dm_block_t *new_root) | |
753 | __dm_written_to_disk(value) | |
754 | { | |
755 | return insert(info, root, keys, value, new_root, NULL); | |
756 | } | |
757 | EXPORT_SYMBOL_GPL(dm_btree_insert); | |
758 | ||
759 | int dm_btree_insert_notify(struct dm_btree_info *info, dm_block_t root, | |
760 | uint64_t *keys, void *value, dm_block_t *new_root, | |
761 | int *inserted) | |
762 | __dm_written_to_disk(value) | |
763 | { | |
764 | return insert(info, root, keys, value, new_root, inserted); | |
765 | } | |
766 | EXPORT_SYMBOL_GPL(dm_btree_insert_notify); | |
767 | ||
768 | /*----------------------------------------------------------------*/ | |
769 | ||
f164e690 JT |
770 | static int find_key(struct ro_spine *s, dm_block_t block, bool find_highest, |
771 | uint64_t *result_key, dm_block_t *next_block) | |
3241b1d3 JT |
772 | { |
773 | int i, r; | |
774 | uint32_t flags; | |
775 | ||
776 | do { | |
777 | r = ro_step(s, block); | |
778 | if (r < 0) | |
779 | return r; | |
780 | ||
781 | flags = le32_to_cpu(ro_node(s)->header.flags); | |
782 | i = le32_to_cpu(ro_node(s)->header.nr_entries); | |
783 | if (!i) | |
784 | return -ENODATA; | |
785 | else | |
786 | i--; | |
787 | ||
f164e690 JT |
788 | if (find_highest) |
789 | *result_key = le64_to_cpu(ro_node(s)->keys[i]); | |
790 | else | |
791 | *result_key = le64_to_cpu(ro_node(s)->keys[0]); | |
792 | ||
3241b1d3 JT |
793 | if (next_block || flags & INTERNAL_NODE) |
794 | block = value64(ro_node(s), i); | |
795 | ||
796 | } while (flags & INTERNAL_NODE); | |
797 | ||
798 | if (next_block) | |
799 | *next_block = block; | |
800 | return 0; | |
801 | } | |
802 | ||
f164e690 JT |
803 | static int dm_btree_find_key(struct dm_btree_info *info, dm_block_t root, |
804 | bool find_highest, uint64_t *result_keys) | |
3241b1d3 JT |
805 | { |
806 | int r = 0, count = 0, level; | |
807 | struct ro_spine spine; | |
808 | ||
809 | init_ro_spine(&spine, info); | |
810 | for (level = 0; level < info->levels; level++) { | |
f164e690 JT |
811 | r = find_key(&spine, root, find_highest, result_keys + level, |
812 | level == info->levels - 1 ? NULL : &root); | |
3241b1d3 JT |
813 | if (r == -ENODATA) { |
814 | r = 0; | |
815 | break; | |
816 | ||
817 | } else if (r) | |
818 | break; | |
819 | ||
820 | count++; | |
821 | } | |
822 | exit_ro_spine(&spine); | |
823 | ||
824 | return r ? r : count; | |
825 | } | |
f164e690 JT |
826 | |
827 | int dm_btree_find_highest_key(struct dm_btree_info *info, dm_block_t root, | |
828 | uint64_t *result_keys) | |
829 | { | |
830 | return dm_btree_find_key(info, root, true, result_keys); | |
831 | } | |
3241b1d3 | 832 | EXPORT_SYMBOL_GPL(dm_btree_find_highest_key); |
4e7f1f90 | 833 | |
f164e690 JT |
834 | int dm_btree_find_lowest_key(struct dm_btree_info *info, dm_block_t root, |
835 | uint64_t *result_keys) | |
836 | { | |
837 | return dm_btree_find_key(info, root, false, result_keys); | |
838 | } | |
839 | EXPORT_SYMBOL_GPL(dm_btree_find_lowest_key); | |
840 | ||
841 | /*----------------------------------------------------------------*/ | |
842 | ||
4e7f1f90 JT |
843 | /* |
844 | * FIXME: We shouldn't use a recursive algorithm when we have limited stack | |
845 | * space. Also this only works for single level trees. | |
846 | */ | |
9b460d36 | 847 | static int walk_node(struct dm_btree_info *info, dm_block_t block, |
4e7f1f90 JT |
848 | int (*fn)(void *context, uint64_t *keys, void *leaf), |
849 | void *context) | |
850 | { | |
851 | int r; | |
852 | unsigned i, nr; | |
9b460d36 | 853 | struct dm_block *node; |
4e7f1f90 JT |
854 | struct btree_node *n; |
855 | uint64_t keys; | |
856 | ||
9b460d36 JT |
857 | r = bn_read_lock(info, block, &node); |
858 | if (r) | |
859 | return r; | |
860 | ||
861 | n = dm_block_data(node); | |
4e7f1f90 JT |
862 | |
863 | nr = le32_to_cpu(n->header.nr_entries); | |
864 | for (i = 0; i < nr; i++) { | |
865 | if (le32_to_cpu(n->header.flags) & INTERNAL_NODE) { | |
9b460d36 | 866 | r = walk_node(info, value64(n, i), fn, context); |
4e7f1f90 JT |
867 | if (r) |
868 | goto out; | |
869 | } else { | |
870 | keys = le64_to_cpu(*key_ptr(n, i)); | |
871 | r = fn(context, &keys, value_ptr(n, i)); | |
872 | if (r) | |
873 | goto out; | |
874 | } | |
875 | } | |
876 | ||
877 | out: | |
9b460d36 | 878 | dm_tm_unlock(info->tm, node); |
4e7f1f90 JT |
879 | return r; |
880 | } | |
881 | ||
882 | int dm_btree_walk(struct dm_btree_info *info, dm_block_t root, | |
883 | int (*fn)(void *context, uint64_t *keys, void *leaf), | |
884 | void *context) | |
885 | { | |
4e7f1f90 | 886 | BUG_ON(info->levels > 1); |
9b460d36 | 887 | return walk_node(info, root, fn, context); |
4e7f1f90 JT |
888 | } |
889 | EXPORT_SYMBOL_GPL(dm_btree_walk); |