Commit | Line | Data |
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427e5fc6 | 1 | /* |
b84de5af | 2 | * Copyright (c) 2007-2008 The DragonFly Project. All rights reserved. |
427e5fc6 MD |
3 | * |
4 | * This code is derived from software contributed to The DragonFly Project | |
5 | * by Matthew Dillon <dillon@backplane.com> | |
6 | * | |
7 | * Redistribution and use in source and binary forms, with or without | |
8 | * modification, are permitted provided that the following conditions | |
9 | * are met: | |
10 | * | |
11 | * 1. Redistributions of source code must retain the above copyright | |
12 | * notice, this list of conditions and the following disclaimer. | |
13 | * 2. Redistributions in binary form must reproduce the above copyright | |
14 | * notice, this list of conditions and the following disclaimer in | |
15 | * the documentation and/or other materials provided with the | |
16 | * distribution. | |
17 | * 3. Neither the name of The DragonFly Project nor the names of its | |
18 | * contributors may be used to endorse or promote products derived | |
19 | * from this software without specific, prior written permission. | |
20 | * | |
21 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | |
22 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | |
23 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS | |
24 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE | |
25 | * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, | |
26 | * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, | |
27 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; | |
28 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED | |
29 | * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, | |
30 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT | |
31 | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
32 | * SUCH DAMAGE. | |
33 | * | |
5c8d05e2 | 34 | * $DragonFly: src/sys/vfs/hammer/hammer_btree.c,v 1.76 2008/08/06 15:38:58 dillon Exp $ |
427e5fc6 MD |
35 | */ |
36 | ||
37 | /* | |
8cd0a023 | 38 | * HAMMER B-Tree index |
427e5fc6 MD |
39 | * |
40 | * HAMMER implements a modified B+Tree. In documentation this will | |
9944ae54 | 41 | * simply be refered to as the HAMMER B-Tree. Basically a HAMMER B-Tree |
427e5fc6 MD |
42 | * looks like a B+Tree (A B-Tree which stores its records only at the leafs |
43 | * of the tree), but adds two additional boundary elements which describe | |
44 | * the left-most and right-most element a node is able to represent. In | |
8cd0a023 | 45 | * otherwords, we have boundary elements at the two ends of a B-Tree node |
427e5fc6 MD |
46 | * instead of sub-tree pointers. |
47 | * | |
8cd0a023 | 48 | * A B-Tree internal node looks like this: |
427e5fc6 MD |
49 | * |
50 | * B N N N N N N B <-- boundary and internal elements | |
51 | * S S S S S S S <-- subtree pointers | |
52 | * | |
8cd0a023 | 53 | * A B-Tree leaf node basically looks like this: |
427e5fc6 MD |
54 | * |
55 | * L L L L L L L L <-- leaf elemenets | |
56 | * | |
8cd0a023 MD |
57 | * The radix for an internal node is 1 less then a leaf but we get a |
58 | * number of significant benefits for our troubles. | |
427e5fc6 | 59 | * |
8cd0a023 MD |
60 | * The big benefit to using a B-Tree containing boundary information |
61 | * is that it is possible to cache pointers into the middle of the tree | |
62 | * and not have to start searches, insertions, OR deletions at the root | |
63 | * node. In particular, searches are able to progress in a definitive | |
64 | * direction from any point in the tree without revisting nodes. This | |
65 | * greatly improves the efficiency of many operations, most especially | |
66 | * record appends. | |
427e5fc6 | 67 | * |
8cd0a023 MD |
68 | * B-Trees also make the stacking of trees fairly straightforward. |
69 | * | |
fe7678ee MD |
70 | * INSERTIONS: A search performed with the intention of doing |
71 | * an insert will guarantee that the terminal leaf node is not full by | |
72 | * splitting full nodes. Splits occur top-down during the dive down the | |
73 | * B-Tree. | |
74 | * | |
75 | * DELETIONS: A deletion makes no attempt to proactively balance the | |
f36a9737 MD |
76 | * tree and will recursively remove nodes that become empty. If a |
77 | * deadlock occurs a deletion may not be able to remove an empty leaf. | |
78 | * Deletions never allow internal nodes to become empty (that would blow | |
79 | * up the boundaries). | |
8cd0a023 MD |
80 | */ |
81 | #include "hammer.h" | |
82 | #include <sys/buf.h> | |
83 | #include <sys/buf2.h> | |
66325755 | 84 | |
8cd0a023 MD |
85 | static int btree_search(hammer_cursor_t cursor, int flags); |
86 | static int btree_split_internal(hammer_cursor_t cursor); | |
87 | static int btree_split_leaf(hammer_cursor_t cursor); | |
46fe7ae1 | 88 | static int btree_remove(hammer_cursor_t cursor); |
fe7678ee | 89 | static int btree_node_is_full(hammer_node_ondisk_t node); |
adf01747 MD |
90 | static int hammer_btree_mirror_propagate(hammer_cursor_t cursor, |
91 | hammer_tid_t mirror_tid); | |
8cd0a023 MD |
92 | static void hammer_make_separator(hammer_base_elm_t key1, |
93 | hammer_base_elm_t key2, hammer_base_elm_t dest); | |
4c038e17 | 94 | static void hammer_cursor_mirror_filter(hammer_cursor_t cursor); |
66325755 MD |
95 | |
96 | /* | |
8cd0a023 MD |
97 | * Iterate records after a search. The cursor is iterated forwards past |
98 | * the current record until a record matching the key-range requirements | |
99 | * is found. ENOENT is returned if the iteration goes past the ending | |
6a37e7e4 | 100 | * key. |
66325755 | 101 | * |
d26d0ae9 MD |
102 | * The iteration is inclusive of key_beg and can be inclusive or exclusive |
103 | * of key_end depending on whether HAMMER_CURSOR_END_INCLUSIVE is set. | |
66325755 | 104 | * |
eaeff70d | 105 | * When doing an as-of search (cursor->asof != 0), key_beg.create_tid |
9582c7da | 106 | * may be modified by B-Tree functions. |
d5530d22 | 107 | * |
8cd0a023 | 108 | * cursor->key_beg may or may not be modified by this function during |
d26d0ae9 MD |
109 | * the iteration. XXX future - in case of an inverted lock we may have |
110 | * to reinitiate the lookup and set key_beg to properly pick up where we | |
111 | * left off. | |
6a37e7e4 MD |
112 | * |
113 | * NOTE! EDEADLK *CANNOT* be returned by this procedure. | |
66325755 MD |
114 | */ |
115 | int | |
8cd0a023 | 116 | hammer_btree_iterate(hammer_cursor_t cursor) |
66325755 | 117 | { |
8cd0a023 MD |
118 | hammer_node_ondisk_t node; |
119 | hammer_btree_elm_t elm; | |
1d4077f7 | 120 | int error = 0; |
66325755 MD |
121 | int r; |
122 | int s; | |
123 | ||
124 | /* | |
8cd0a023 | 125 | * Skip past the current record |
66325755 | 126 | */ |
8cd0a023 | 127 | node = cursor->node->ondisk; |
a89aec1b MD |
128 | if (node == NULL) |
129 | return(ENOENT); | |
c0ade690 MD |
130 | if (cursor->index < node->count && |
131 | (cursor->flags & HAMMER_CURSOR_ATEDISK)) { | |
66325755 | 132 | ++cursor->index; |
c0ade690 | 133 | } |
66325755 | 134 | |
8cd0a023 MD |
135 | /* |
136 | * Loop until an element is found or we are done. | |
137 | */ | |
66325755 MD |
138 | for (;;) { |
139 | /* | |
8cd0a023 MD |
140 | * We iterate up the tree and then index over one element |
141 | * while we are at the last element in the current node. | |
142 | * | |
47197d71 | 143 | * If we are at the root of the filesystem, cursor_up |
8cd0a023 MD |
144 | * returns ENOENT. |
145 | * | |
66325755 MD |
146 | * XXX this could be optimized by storing the information in |
147 | * the parent reference. | |
195c19a1 MD |
148 | * |
149 | * XXX we can lose the node lock temporarily, this could mess | |
150 | * up our scan. | |
66325755 | 151 | */ |
47637bff | 152 | ++hammer_stats_btree_iterations; |
77fec802 MD |
153 | hammer_flusher_clean_loose_ios(cursor->trans->hmp); |
154 | ||
8cd0a023 | 155 | if (cursor->index == node->count) { |
a84a197d MD |
156 | if (hammer_debug_btree) { |
157 | kprintf("BRACKETU %016llx[%d] -> %016llx[%d] (td=%p)\n", | |
973c11b9 | 158 | (long long)cursor->node->node_offset, |
a84a197d | 159 | cursor->index, |
973c11b9 | 160 | (long long)(cursor->parent ? cursor->parent->node_offset : -1), |
a84a197d MD |
161 | cursor->parent_index, |
162 | curthread); | |
163 | } | |
164 | KKASSERT(cursor->parent == NULL || cursor->parent->ondisk->elms[cursor->parent_index].internal.subtree_offset == cursor->node->node_offset); | |
6a37e7e4 | 165 | error = hammer_cursor_up(cursor); |
8cd0a023 MD |
166 | if (error) |
167 | break; | |
46fe7ae1 | 168 | /* reload stale pointer */ |
8cd0a023 MD |
169 | node = cursor->node->ondisk; |
170 | KKASSERT(cursor->index != node->count); | |
2f85fa4d MD |
171 | |
172 | /* | |
173 | * If we are reblocking we want to return internal | |
1775b6a0 MD |
174 | * nodes. Note that the internal node will be |
175 | * returned multiple times, on each upward recursion | |
176 | * from its children. The caller selects which | |
177 | * revisit it cares about (usually first or last only). | |
2f85fa4d MD |
178 | */ |
179 | if (cursor->flags & HAMMER_CURSOR_REBLOCKING) { | |
180 | cursor->flags |= HAMMER_CURSOR_ATEDISK; | |
181 | return(0); | |
182 | } | |
8cd0a023 MD |
183 | ++cursor->index; |
184 | continue; | |
66325755 MD |
185 | } |
186 | ||
187 | /* | |
d26d0ae9 MD |
188 | * Check internal or leaf element. Determine if the record |
189 | * at the cursor has gone beyond the end of our range. | |
66325755 | 190 | * |
47197d71 | 191 | * We recurse down through internal nodes. |
66325755 | 192 | */ |
8cd0a023 MD |
193 | if (node->type == HAMMER_BTREE_TYPE_INTERNAL) { |
194 | elm = &node->elms[cursor->index]; | |
c82af904 | 195 | |
d26d0ae9 MD |
196 | r = hammer_btree_cmp(&cursor->key_end, &elm[0].base); |
197 | s = hammer_btree_cmp(&cursor->key_beg, &elm[1].base); | |
b3deaf57 | 198 | if (hammer_debug_btree) { |
2f85fa4d | 199 | kprintf("BRACKETL %016llx[%d] %016llx %02x %016llx lo=%02x %d (td=%p)\n", |
973c11b9 | 200 | (long long)cursor->node->node_offset, |
eaeff70d | 201 | cursor->index, |
973c11b9 | 202 | (long long)elm[0].internal.base.obj_id, |
b3deaf57 | 203 | elm[0].internal.base.rec_type, |
973c11b9 | 204 | (long long)elm[0].internal.base.key, |
2f85fa4d | 205 | elm[0].internal.base.localization, |
a84a197d MD |
206 | r, |
207 | curthread | |
b3deaf57 | 208 | ); |
2f85fa4d | 209 | kprintf("BRACKETR %016llx[%d] %016llx %02x %016llx lo=%02x %d\n", |
973c11b9 | 210 | (long long)cursor->node->node_offset, |
eaeff70d | 211 | cursor->index + 1, |
973c11b9 | 212 | (long long)elm[1].internal.base.obj_id, |
b3deaf57 | 213 | elm[1].internal.base.rec_type, |
973c11b9 | 214 | (long long)elm[1].internal.base.key, |
2f85fa4d | 215 | elm[1].internal.base.localization, |
b3deaf57 MD |
216 | s |
217 | ); | |
218 | } | |
219 | ||
d26d0ae9 MD |
220 | if (r < 0) { |
221 | error = ENOENT; | |
222 | break; | |
66325755 | 223 | } |
fe7678ee MD |
224 | if (r == 0 && (cursor->flags & |
225 | HAMMER_CURSOR_END_INCLUSIVE) == 0) { | |
d26d0ae9 | 226 | error = ENOENT; |
8cd0a023 | 227 | break; |
d26d0ae9 MD |
228 | } |
229 | KKASSERT(s <= 0); | |
6a37e7e4 MD |
230 | |
231 | /* | |
f36a9737 | 232 | * Better not be zero |
6a37e7e4 | 233 | */ |
f36a9737 MD |
234 | KKASSERT(elm->internal.subtree_offset != 0); |
235 | ||
c82af904 MD |
236 | /* |
237 | * If running the mirror filter see if we can skip | |
4c038e17 MD |
238 | * one or more entire sub-trees. If we can we |
239 | * return the internal mode and the caller processes | |
240 | * the skipped range (see mirror_read) | |
c82af904 MD |
241 | */ |
242 | if (cursor->flags & HAMMER_CURSOR_MIRROR_FILTERED) { | |
243 | if (elm->internal.mirror_tid < | |
4c038e17 MD |
244 | cursor->cmirror->mirror_tid) { |
245 | hammer_cursor_mirror_filter(cursor); | |
246 | return(0); | |
c82af904 MD |
247 | } |
248 | } | |
249 | ||
f36a9737 MD |
250 | error = hammer_cursor_down(cursor); |
251 | if (error) | |
252 | break; | |
253 | KKASSERT(cursor->index == 0); | |
46fe7ae1 MD |
254 | /* reload stale pointer */ |
255 | node = cursor->node->ondisk; | |
fe7678ee | 256 | continue; |
d26d0ae9 MD |
257 | } else { |
258 | elm = &node->elms[cursor->index]; | |
259 | r = hammer_btree_cmp(&cursor->key_end, &elm->base); | |
b3deaf57 | 260 | if (hammer_debug_btree) { |
2f85fa4d | 261 | kprintf("ELEMENT %016llx:%d %c %016llx %02x %016llx lo=%02x %d\n", |
973c11b9 | 262 | (long long)cursor->node->node_offset, |
eaeff70d MD |
263 | cursor->index, |
264 | (elm[0].leaf.base.btype ? | |
265 | elm[0].leaf.base.btype : '?'), | |
973c11b9 | 266 | (long long)elm[0].leaf.base.obj_id, |
b3deaf57 | 267 | elm[0].leaf.base.rec_type, |
973c11b9 | 268 | (long long)elm[0].leaf.base.key, |
2f85fa4d | 269 | elm[0].leaf.base.localization, |
b3deaf57 MD |
270 | r |
271 | ); | |
272 | } | |
d26d0ae9 MD |
273 | if (r < 0) { |
274 | error = ENOENT; | |
275 | break; | |
276 | } | |
b33e2cc0 MD |
277 | |
278 | /* | |
279 | * We support both end-inclusive and | |
280 | * end-exclusive searches. | |
281 | */ | |
282 | if (r == 0 && | |
283 | (cursor->flags & HAMMER_CURSOR_END_INCLUSIVE) == 0) { | |
284 | error = ENOENT; | |
285 | break; | |
286 | } | |
287 | ||
fe7678ee MD |
288 | switch(elm->leaf.base.btype) { |
289 | case HAMMER_BTREE_TYPE_RECORD: | |
290 | if ((cursor->flags & HAMMER_CURSOR_ASOF) && | |
291 | hammer_btree_chkts(cursor->asof, &elm->base)) { | |
292 | ++cursor->index; | |
293 | continue; | |
294 | } | |
1d4077f7 | 295 | error = 0; |
fe7678ee | 296 | break; |
fe7678ee MD |
297 | default: |
298 | error = EINVAL; | |
299 | break; | |
d26d0ae9 | 300 | } |
fe7678ee MD |
301 | if (error) |
302 | break; | |
66325755 | 303 | } |
46fe7ae1 MD |
304 | /* |
305 | * node pointer invalid after loop | |
306 | */ | |
66325755 MD |
307 | |
308 | /* | |
d26d0ae9 | 309 | * Return entry |
66325755 | 310 | */ |
b3deaf57 MD |
311 | if (hammer_debug_btree) { |
312 | int i = cursor->index; | |
313 | hammer_btree_elm_t elm = &cursor->node->ondisk->elms[i]; | |
2f85fa4d | 314 | kprintf("ITERATE %p:%d %016llx %02x %016llx lo=%02x\n", |
b3deaf57 | 315 | cursor->node, i, |
973c11b9 | 316 | (long long)elm->internal.base.obj_id, |
b3deaf57 | 317 | elm->internal.base.rec_type, |
973c11b9 | 318 | (long long)elm->internal.base.key, |
2f85fa4d | 319 | elm->internal.base.localization |
b3deaf57 MD |
320 | ); |
321 | } | |
d26d0ae9 | 322 | return(0); |
427e5fc6 | 323 | } |
66325755 | 324 | return(error); |
427e5fc6 MD |
325 | } |
326 | ||
4c038e17 MD |
327 | /* |
328 | * We hit an internal element that we could skip as part of a mirroring | |
329 | * scan. Calculate the entire range being skipped. | |
330 | * | |
331 | * It is important to include any gaps between the parent's left_bound | |
332 | * and the node's left_bound, and same goes for the right side. | |
333 | */ | |
334 | static void | |
335 | hammer_cursor_mirror_filter(hammer_cursor_t cursor) | |
336 | { | |
337 | struct hammer_cmirror *cmirror; | |
338 | hammer_node_ondisk_t ondisk; | |
339 | hammer_btree_elm_t elm; | |
340 | ||
341 | ondisk = cursor->node->ondisk; | |
342 | cmirror = cursor->cmirror; | |
343 | ||
344 | /* | |
345 | * Calculate the skipped range | |
346 | */ | |
347 | elm = &ondisk->elms[cursor->index]; | |
348 | if (cursor->index == 0) | |
349 | cmirror->skip_beg = *cursor->left_bound; | |
350 | else | |
351 | cmirror->skip_beg = elm->internal.base; | |
352 | while (cursor->index < ondisk->count) { | |
353 | if (elm->internal.mirror_tid >= cmirror->mirror_tid) | |
354 | break; | |
355 | ++cursor->index; | |
356 | ++elm; | |
357 | } | |
358 | if (cursor->index == ondisk->count) | |
359 | cmirror->skip_end = *cursor->right_bound; | |
360 | else | |
361 | cmirror->skip_end = elm->internal.base; | |
362 | ||
363 | /* | |
364 | * clip the returned result. | |
365 | */ | |
366 | if (hammer_btree_cmp(&cmirror->skip_beg, &cursor->key_beg) < 0) | |
367 | cmirror->skip_beg = cursor->key_beg; | |
368 | if (hammer_btree_cmp(&cmirror->skip_end, &cursor->key_end) > 0) | |
369 | cmirror->skip_end = cursor->key_end; | |
370 | } | |
371 | ||
32c90105 MD |
372 | /* |
373 | * Iterate in the reverse direction. This is used by the pruning code to | |
374 | * avoid overlapping records. | |
375 | */ | |
376 | int | |
377 | hammer_btree_iterate_reverse(hammer_cursor_t cursor) | |
378 | { | |
379 | hammer_node_ondisk_t node; | |
380 | hammer_btree_elm_t elm; | |
f75df937 | 381 | int error = 0; |
32c90105 MD |
382 | int r; |
383 | int s; | |
384 | ||
4c038e17 MD |
385 | /* mirror filtering not supported for reverse iteration */ |
386 | KKASSERT ((cursor->flags & HAMMER_CURSOR_MIRROR_FILTERED) == 0); | |
387 | ||
32c90105 MD |
388 | /* |
389 | * Skip past the current record. For various reasons the cursor | |
390 | * may end up set to -1 or set to point at the end of the current | |
391 | * node. These cases must be addressed. | |
392 | */ | |
393 | node = cursor->node->ondisk; | |
394 | if (node == NULL) | |
395 | return(ENOENT); | |
396 | if (cursor->index != -1 && | |
397 | (cursor->flags & HAMMER_CURSOR_ATEDISK)) { | |
398 | --cursor->index; | |
399 | } | |
400 | if (cursor->index == cursor->node->ondisk->count) | |
401 | --cursor->index; | |
402 | ||
403 | /* | |
404 | * Loop until an element is found or we are done. | |
405 | */ | |
406 | for (;;) { | |
77fec802 MD |
407 | ++hammer_stats_btree_iterations; |
408 | hammer_flusher_clean_loose_ios(cursor->trans->hmp); | |
409 | ||
32c90105 MD |
410 | /* |
411 | * We iterate up the tree and then index over one element | |
412 | * while we are at the last element in the current node. | |
32c90105 MD |
413 | */ |
414 | if (cursor->index == -1) { | |
415 | error = hammer_cursor_up(cursor); | |
416 | if (error) { | |
417 | cursor->index = 0; /* sanity */ | |
418 | break; | |
419 | } | |
420 | /* reload stale pointer */ | |
421 | node = cursor->node->ondisk; | |
422 | KKASSERT(cursor->index != node->count); | |
423 | --cursor->index; | |
424 | continue; | |
425 | } | |
426 | ||
427 | /* | |
428 | * Check internal or leaf element. Determine if the record | |
429 | * at the cursor has gone beyond the end of our range. | |
430 | * | |
47197d71 | 431 | * We recurse down through internal nodes. |
32c90105 MD |
432 | */ |
433 | KKASSERT(cursor->index != node->count); | |
434 | if (node->type == HAMMER_BTREE_TYPE_INTERNAL) { | |
435 | elm = &node->elms[cursor->index]; | |
436 | r = hammer_btree_cmp(&cursor->key_end, &elm[0].base); | |
437 | s = hammer_btree_cmp(&cursor->key_beg, &elm[1].base); | |
438 | if (hammer_debug_btree) { | |
2f85fa4d | 439 | kprintf("BRACKETL %016llx[%d] %016llx %02x %016llx lo=%02x %d\n", |
973c11b9 | 440 | (long long)cursor->node->node_offset, |
32c90105 | 441 | cursor->index, |
973c11b9 | 442 | (long long)elm[0].internal.base.obj_id, |
32c90105 | 443 | elm[0].internal.base.rec_type, |
973c11b9 | 444 | (long long)elm[0].internal.base.key, |
2f85fa4d | 445 | elm[0].internal.base.localization, |
32c90105 MD |
446 | r |
447 | ); | |
2f85fa4d | 448 | kprintf("BRACKETR %016llx[%d] %016llx %02x %016llx lo=%02x %d\n", |
973c11b9 | 449 | (long long)cursor->node->node_offset, |
32c90105 | 450 | cursor->index + 1, |
973c11b9 | 451 | (long long)elm[1].internal.base.obj_id, |
32c90105 | 452 | elm[1].internal.base.rec_type, |
973c11b9 | 453 | (long long)elm[1].internal.base.key, |
2f85fa4d | 454 | elm[1].internal.base.localization, |
32c90105 MD |
455 | s |
456 | ); | |
457 | } | |
458 | ||
459 | if (s >= 0) { | |
460 | error = ENOENT; | |
461 | break; | |
462 | } | |
463 | KKASSERT(r >= 0); | |
464 | ||
465 | /* | |
f36a9737 | 466 | * Better not be zero |
32c90105 | 467 | */ |
f36a9737 MD |
468 | KKASSERT(elm->internal.subtree_offset != 0); |
469 | ||
470 | error = hammer_cursor_down(cursor); | |
471 | if (error) | |
472 | break; | |
473 | KKASSERT(cursor->index == 0); | |
32c90105 MD |
474 | /* reload stale pointer */ |
475 | node = cursor->node->ondisk; | |
f36a9737 MD |
476 | |
477 | /* this can assign -1 if the leaf was empty */ | |
478 | cursor->index = node->count - 1; | |
32c90105 MD |
479 | continue; |
480 | } else { | |
481 | elm = &node->elms[cursor->index]; | |
482 | s = hammer_btree_cmp(&cursor->key_beg, &elm->base); | |
483 | if (hammer_debug_btree) { | |
2f85fa4d | 484 | kprintf("ELEMENT %016llx:%d %c %016llx %02x %016llx lo=%02x %d\n", |
973c11b9 | 485 | (long long)cursor->node->node_offset, |
32c90105 MD |
486 | cursor->index, |
487 | (elm[0].leaf.base.btype ? | |
488 | elm[0].leaf.base.btype : '?'), | |
973c11b9 | 489 | (long long)elm[0].leaf.base.obj_id, |
32c90105 | 490 | elm[0].leaf.base.rec_type, |
973c11b9 | 491 | (long long)elm[0].leaf.base.key, |
2f85fa4d | 492 | elm[0].leaf.base.localization, |
32c90105 MD |
493 | s |
494 | ); | |
495 | } | |
496 | if (s > 0) { | |
497 | error = ENOENT; | |
498 | break; | |
499 | } | |
500 | ||
501 | switch(elm->leaf.base.btype) { | |
502 | case HAMMER_BTREE_TYPE_RECORD: | |
503 | if ((cursor->flags & HAMMER_CURSOR_ASOF) && | |
504 | hammer_btree_chkts(cursor->asof, &elm->base)) { | |
505 | --cursor->index; | |
506 | continue; | |
507 | } | |
f75df937 | 508 | error = 0; |
32c90105 | 509 | break; |
32c90105 MD |
510 | default: |
511 | error = EINVAL; | |
512 | break; | |
513 | } | |
514 | if (error) | |
515 | break; | |
516 | } | |
517 | /* | |
518 | * node pointer invalid after loop | |
519 | */ | |
520 | ||
521 | /* | |
522 | * Return entry | |
523 | */ | |
524 | if (hammer_debug_btree) { | |
525 | int i = cursor->index; | |
526 | hammer_btree_elm_t elm = &cursor->node->ondisk->elms[i]; | |
2f85fa4d | 527 | kprintf("ITERATE %p:%d %016llx %02x %016llx lo=%02x\n", |
32c90105 | 528 | cursor->node, i, |
973c11b9 | 529 | (long long)elm->internal.base.obj_id, |
32c90105 | 530 | elm->internal.base.rec_type, |
973c11b9 | 531 | (long long)elm->internal.base.key, |
2f85fa4d | 532 | elm->internal.base.localization |
32c90105 MD |
533 | ); |
534 | } | |
535 | return(0); | |
536 | } | |
537 | return(error); | |
538 | } | |
539 | ||
427e5fc6 | 540 | /* |
8cd0a023 | 541 | * Lookup cursor->key_beg. 0 is returned on success, ENOENT if the entry |
6a37e7e4 MD |
542 | * could not be found, EDEADLK if inserting and a retry is needed, and a |
543 | * fatal error otherwise. When retrying, the caller must terminate the | |
eaeff70d | 544 | * cursor and reinitialize it. EDEADLK cannot be returned if not inserting. |
8cd0a023 MD |
545 | * |
546 | * The cursor is suitably positioned for a deletion on success, and suitably | |
eaeff70d MD |
547 | * positioned for an insertion on ENOENT if HAMMER_CURSOR_INSERT was |
548 | * specified. | |
427e5fc6 | 549 | * |
47197d71 | 550 | * The cursor may begin anywhere, the search will traverse the tree in |
8cd0a023 | 551 | * either direction to locate the requested element. |
eaeff70d MD |
552 | * |
553 | * Most of the logic implementing historical searches is handled here. We | |
9582c7da MD |
554 | * do an initial lookup with create_tid set to the asof TID. Due to the |
555 | * way records are laid out, a backwards iteration may be required if | |
eaeff70d MD |
556 | * ENOENT is returned to locate the historical record. Here's the |
557 | * problem: | |
558 | * | |
9582c7da | 559 | * create_tid: 10 15 20 |
eaeff70d MD |
560 | * LEAF1 LEAF2 |
561 | * records: (11) (18) | |
562 | * | |
9582c7da MD |
563 | * Lets say we want to do a lookup AS-OF timestamp 17. We will traverse |
564 | * LEAF2 but the only record in LEAF2 has a create_tid of 18, which is | |
565 | * not visible and thus causes ENOENT to be returned. We really need | |
566 | * to check record 11 in LEAF1. If it also fails then the search fails | |
567 | * (e.g. it might represent the range 11-16 and thus still not match our | |
f36a9737 MD |
568 | * AS-OF timestamp of 17). Note that LEAF1 could be empty, requiring |
569 | * further iterations. | |
b33e2cc0 | 570 | * |
9582c7da MD |
571 | * If this case occurs btree_search() will set HAMMER_CURSOR_CREATE_CHECK |
572 | * and the cursor->create_check TID if an iteration might be needed. | |
573 | * In the above example create_check would be set to 14. | |
427e5fc6 MD |
574 | */ |
575 | int | |
8cd0a023 | 576 | hammer_btree_lookup(hammer_cursor_t cursor) |
427e5fc6 | 577 | { |
66325755 MD |
578 | int error; |
579 | ||
98da6d8c MD |
580 | KKASSERT ((cursor->flags & HAMMER_CURSOR_INSERT) == 0 || |
581 | cursor->trans->sync_lock_refs > 0); | |
cb51be26 | 582 | ++hammer_stats_btree_lookups; |
d5530d22 | 583 | if (cursor->flags & HAMMER_CURSOR_ASOF) { |
eaeff70d | 584 | KKASSERT((cursor->flags & HAMMER_CURSOR_INSERT) == 0); |
9582c7da | 585 | cursor->key_beg.create_tid = cursor->asof; |
eaeff70d | 586 | for (;;) { |
9582c7da | 587 | cursor->flags &= ~HAMMER_CURSOR_CREATE_CHECK; |
d5530d22 | 588 | error = btree_search(cursor, 0); |
b33e2cc0 | 589 | if (error != ENOENT || |
9582c7da | 590 | (cursor->flags & HAMMER_CURSOR_CREATE_CHECK) == 0) { |
b33e2cc0 MD |
591 | /* |
592 | * Stop if no error. | |
593 | * Stop if error other then ENOENT. | |
594 | * Stop if ENOENT and not special case. | |
595 | */ | |
eaeff70d MD |
596 | break; |
597 | } | |
32c90105 MD |
598 | if (hammer_debug_btree) { |
599 | kprintf("CREATE_CHECK %016llx\n", | |
973c11b9 | 600 | (long long)cursor->create_check); |
32c90105 | 601 | } |
9582c7da | 602 | cursor->key_beg.create_tid = cursor->create_check; |
eaeff70d MD |
603 | /* loop */ |
604 | } | |
d5530d22 MD |
605 | } else { |
606 | error = btree_search(cursor, 0); | |
607 | } | |
bf3b416b | 608 | if (error == 0) |
8cd0a023 | 609 | error = hammer_btree_extract(cursor, cursor->flags); |
66325755 MD |
610 | return(error); |
611 | } | |
612 | ||
d26d0ae9 MD |
613 | /* |
614 | * Execute the logic required to start an iteration. The first record | |
615 | * located within the specified range is returned and iteration control | |
616 | * flags are adjusted for successive hammer_btree_iterate() calls. | |
3214ade6 MD |
617 | * |
618 | * Set ATEDISK so a low-level caller can call btree_first/btree_iterate | |
619 | * in a loop without worrying about it. Higher-level merged searches will | |
620 | * adjust the flag appropriately. | |
d26d0ae9 MD |
621 | */ |
622 | int | |
623 | hammer_btree_first(hammer_cursor_t cursor) | |
624 | { | |
625 | int error; | |
626 | ||
627 | error = hammer_btree_lookup(cursor); | |
628 | if (error == ENOENT) { | |
629 | cursor->flags &= ~HAMMER_CURSOR_ATEDISK; | |
630 | error = hammer_btree_iterate(cursor); | |
631 | } | |
632 | cursor->flags |= HAMMER_CURSOR_ATEDISK; | |
633 | return(error); | |
634 | } | |
635 | ||
32c90105 MD |
636 | /* |
637 | * Similarly but for an iteration in the reverse direction. | |
814387f6 MD |
638 | * |
639 | * Set ATEDISK when iterating backwards to skip the current entry, | |
640 | * which after an ENOENT lookup will be pointing beyond our end point. | |
3214ade6 MD |
641 | * |
642 | * Set ATEDISK so a low-level caller can call btree_last/btree_iterate_reverse | |
643 | * in a loop without worrying about it. Higher-level merged searches will | |
644 | * adjust the flag appropriately. | |
32c90105 MD |
645 | */ |
646 | int | |
647 | hammer_btree_last(hammer_cursor_t cursor) | |
648 | { | |
649 | struct hammer_base_elm save; | |
650 | int error; | |
651 | ||
652 | save = cursor->key_beg; | |
653 | cursor->key_beg = cursor->key_end; | |
654 | error = hammer_btree_lookup(cursor); | |
655 | cursor->key_beg = save; | |
656 | if (error == ENOENT || | |
657 | (cursor->flags & HAMMER_CURSOR_END_INCLUSIVE) == 0) { | |
814387f6 | 658 | cursor->flags |= HAMMER_CURSOR_ATEDISK; |
32c90105 MD |
659 | error = hammer_btree_iterate_reverse(cursor); |
660 | } | |
661 | cursor->flags |= HAMMER_CURSOR_ATEDISK; | |
662 | return(error); | |
663 | } | |
664 | ||
8cd0a023 MD |
665 | /* |
666 | * Extract the record and/or data associated with the cursor's current | |
667 | * position. Any prior record or data stored in the cursor is replaced. | |
668 | * The cursor must be positioned at a leaf node. | |
669 | * | |
47197d71 | 670 | * NOTE: All extractions occur at the leaf of the B-Tree. |
8cd0a023 | 671 | */ |
66325755 | 672 | int |
8cd0a023 | 673 | hammer_btree_extract(hammer_cursor_t cursor, int flags) |
66325755 | 674 | { |
8cd0a023 MD |
675 | hammer_node_ondisk_t node; |
676 | hammer_btree_elm_t elm; | |
47197d71 | 677 | hammer_off_t data_off; |
bac808fe | 678 | hammer_mount_t hmp; |
19619882 | 679 | int32_t data_len; |
427e5fc6 | 680 | int error; |
427e5fc6 | 681 | |
8cd0a023 | 682 | /* |
427e5fc6 MD |
683 | * The case where the data reference resolves to the same buffer |
684 | * as the record reference must be handled. | |
685 | */ | |
8cd0a023 | 686 | node = cursor->node->ondisk; |
8cd0a023 | 687 | elm = &node->elms[cursor->index]; |
40043e7f MD |
688 | cursor->data = NULL; |
689 | hmp = cursor->node->hmp; | |
66325755 | 690 | |
d26d0ae9 | 691 | /* |
fe7678ee | 692 | * There is nothing to extract for an internal element. |
d26d0ae9 | 693 | */ |
fe7678ee MD |
694 | if (node->type == HAMMER_BTREE_TYPE_INTERNAL) |
695 | return(EINVAL); | |
696 | ||
47197d71 MD |
697 | /* |
698 | * Only record types have data. | |
699 | */ | |
fe7678ee | 700 | KKASSERT(node->type == HAMMER_BTREE_TYPE_LEAF); |
11ad5ade | 701 | cursor->leaf = &elm->leaf; |
4a2796f3 MD |
702 | |
703 | if ((flags & HAMMER_CURSOR_GET_DATA) == 0) | |
704 | return(0); | |
47197d71 | 705 | if (elm->leaf.base.btype != HAMMER_BTREE_TYPE_RECORD) |
4a2796f3 | 706 | return(0); |
47197d71 | 707 | data_off = elm->leaf.data_offset; |
19619882 | 708 | data_len = elm->leaf.data_len; |
47197d71 | 709 | if (data_off == 0) |
4a2796f3 | 710 | return(0); |
d26d0ae9 | 711 | |
4a2796f3 MD |
712 | /* |
713 | * Load the data | |
714 | */ | |
715 | KKASSERT(data_len >= 0 && data_len <= HAMMER_XBUFSIZE); | |
716 | cursor->data = hammer_bread_ext(hmp, data_off, data_len, | |
717 | &error, &cursor->data_buffer); | |
e469566b MD |
718 | if (hammer_crc_test_leaf(cursor->data, &elm->leaf) == 0) { |
719 | kprintf("CRC DATA @ %016llx/%d FAILED\n", | |
973c11b9 | 720 | (long long)elm->leaf.data_offset, elm->leaf.data_len); |
4c286c36 MD |
721 | if (hammer_debug_debug & 0x0001) |
722 | Debugger("CRC FAILED: DATA"); | |
723 | if (cursor->trans->flags & HAMMER_TRANSF_CRCDOM) | |
724 | error = EDOM; /* less critical (mirroring) */ | |
725 | else | |
726 | error = EIO; /* critical */ | |
e469566b | 727 | } |
427e5fc6 MD |
728 | return(error); |
729 | } | |
730 | ||
731 | ||
732 | /* | |
8cd0a023 MD |
733 | * Insert a leaf element into the B-Tree at the current cursor position. |
734 | * The cursor is positioned such that the element at and beyond the cursor | |
735 | * are shifted to make room for the new record. | |
736 | * | |
a89aec1b | 737 | * The caller must call hammer_btree_lookup() with the HAMMER_CURSOR_INSERT |
8cd0a023 MD |
738 | * flag set and that call must return ENOENT before this function can be |
739 | * called. | |
740 | * | |
d36ec43b | 741 | * The caller may depend on the cursor's exclusive lock after return to |
1f07f686 | 742 | * interlock frontend visibility (see HAMMER_RECF_CONVERT_DELETE). |
d36ec43b | 743 | * |
8cd0a023 | 744 | * ENOSPC is returned if there is no room to insert a new record. |
427e5fc6 MD |
745 | */ |
746 | int | |
602c6cb8 MD |
747 | hammer_btree_insert(hammer_cursor_t cursor, hammer_btree_leaf_elm_t elm, |
748 | int *doprop) | |
427e5fc6 | 749 | { |
8cd0a023 | 750 | hammer_node_ondisk_t node; |
427e5fc6 | 751 | int i; |
6a37e7e4 MD |
752 | int error; |
753 | ||
602c6cb8 | 754 | *doprop = 0; |
7bc5b8c2 | 755 | if ((error = hammer_cursor_upgrade_node(cursor)) != 0) |
6a37e7e4 | 756 | return(error); |
cb51be26 | 757 | ++hammer_stats_btree_inserts; |
427e5fc6 | 758 | |
427e5fc6 MD |
759 | /* |
760 | * Insert the element at the leaf node and update the count in the | |
761 | * parent. It is possible for parent to be NULL, indicating that | |
47197d71 MD |
762 | * the filesystem's ROOT B-Tree node is a leaf itself, which is |
763 | * possible. The root inode can never be deleted so the leaf should | |
764 | * never be empty. | |
427e5fc6 MD |
765 | * |
766 | * Remember that the right-hand boundary is not included in the | |
767 | * count. | |
768 | */ | |
36f82b23 | 769 | hammer_modify_node_all(cursor->trans, cursor->node); |
8cd0a023 | 770 | node = cursor->node->ondisk; |
427e5fc6 | 771 | i = cursor->index; |
fe7678ee | 772 | KKASSERT(elm->base.btype != 0); |
8cd0a023 MD |
773 | KKASSERT(node->type == HAMMER_BTREE_TYPE_LEAF); |
774 | KKASSERT(node->count < HAMMER_BTREE_LEAF_ELMS); | |
775 | if (i != node->count) { | |
776 | bcopy(&node->elms[i], &node->elms[i+1], | |
777 | (node->count - i) * sizeof(*elm)); | |
778 | } | |
11ad5ade | 779 | node->elms[i].leaf = *elm; |
8cd0a023 | 780 | ++node->count; |
e4a5ff06 | 781 | hammer_cursor_inserted_element(cursor->node, i); |
c82af904 MD |
782 | |
783 | /* | |
784 | * Update the leaf node's aggregate mirror_tid for mirroring | |
785 | * support. | |
786 | */ | |
602c6cb8 | 787 | if (node->mirror_tid < elm->base.delete_tid) { |
c82af904 | 788 | node->mirror_tid = elm->base.delete_tid; |
602c6cb8 MD |
789 | *doprop = 1; |
790 | } | |
791 | if (node->mirror_tid < elm->base.create_tid) { | |
c82af904 | 792 | node->mirror_tid = elm->base.create_tid; |
602c6cb8 | 793 | *doprop = 1; |
c82af904 | 794 | } |
602c6cb8 | 795 | hammer_modify_node_done(cursor->node); |
c82af904 | 796 | |
eaeff70d | 797 | /* |
47197d71 | 798 | * Debugging sanity checks. |
eaeff70d | 799 | */ |
11ad5ade MD |
800 | KKASSERT(hammer_btree_cmp(cursor->left_bound, &elm->base) <= 0); |
801 | KKASSERT(hammer_btree_cmp(cursor->right_bound, &elm->base) > 0); | |
eaeff70d | 802 | if (i) { |
11ad5ade | 803 | KKASSERT(hammer_btree_cmp(&node->elms[i-1].leaf.base, &elm->base) < 0); |
eaeff70d | 804 | } |
b3deaf57 | 805 | if (i != node->count - 1) |
11ad5ade | 806 | KKASSERT(hammer_btree_cmp(&node->elms[i+1].leaf.base, &elm->base) > 0); |
b3deaf57 | 807 | |
427e5fc6 MD |
808 | return(0); |
809 | } | |
810 | ||
811 | /* | |
fe7678ee | 812 | * Delete a record from the B-Tree at the current cursor position. |
8cd0a023 MD |
813 | * The cursor is positioned such that the current element is the one |
814 | * to be deleted. | |
815 | * | |
195c19a1 MD |
816 | * On return the cursor will be positioned after the deleted element and |
817 | * MAY point to an internal node. It will be suitable for the continuation | |
818 | * of an iteration but not for an insertion or deletion. | |
8cd0a023 | 819 | * |
195c19a1 | 820 | * Deletions will attempt to partially rebalance the B-Tree in an upward |
f36a9737 MD |
821 | * direction, but will terminate rather then deadlock. Empty internal nodes |
822 | * are never allowed by a deletion which deadlocks may end up giving us an | |
823 | * empty leaf. The pruner will clean up and rebalance the tree. | |
46fe7ae1 MD |
824 | * |
825 | * This function can return EDEADLK, requiring the caller to retry the | |
826 | * operation after clearing the deadlock. | |
427e5fc6 MD |
827 | */ |
828 | int | |
8cd0a023 | 829 | hammer_btree_delete(hammer_cursor_t cursor) |
427e5fc6 | 830 | { |
8cd0a023 MD |
831 | hammer_node_ondisk_t ondisk; |
832 | hammer_node_t node; | |
833 | hammer_node_t parent; | |
8cd0a023 | 834 | int error; |
427e5fc6 MD |
835 | int i; |
836 | ||
98da6d8c | 837 | KKASSERT (cursor->trans->sync_lock_refs > 0); |
6a37e7e4 MD |
838 | if ((error = hammer_cursor_upgrade(cursor)) != 0) |
839 | return(error); | |
cb51be26 | 840 | ++hammer_stats_btree_deletes; |
6a37e7e4 | 841 | |
427e5fc6 | 842 | /* |
8cd0a023 | 843 | * Delete the element from the leaf node. |
427e5fc6 | 844 | * |
8cd0a023 | 845 | * Remember that leaf nodes do not have boundaries. |
427e5fc6 | 846 | */ |
8cd0a023 MD |
847 | node = cursor->node; |
848 | ondisk = node->ondisk; | |
427e5fc6 MD |
849 | i = cursor->index; |
850 | ||
8cd0a023 | 851 | KKASSERT(ondisk->type == HAMMER_BTREE_TYPE_LEAF); |
fe7678ee | 852 | KKASSERT(i >= 0 && i < ondisk->count); |
36f82b23 | 853 | hammer_modify_node_all(cursor->trans, node); |
8cd0a023 MD |
854 | if (i + 1 != ondisk->count) { |
855 | bcopy(&ondisk->elms[i+1], &ondisk->elms[i], | |
856 | (ondisk->count - i - 1) * sizeof(ondisk->elms[0])); | |
857 | } | |
858 | --ondisk->count; | |
10a5d1ba | 859 | hammer_modify_node_done(node); |
b3bad96f | 860 | hammer_cursor_deleted_element(node, i); |
fe7678ee MD |
861 | |
862 | /* | |
863 | * Validate local parent | |
864 | */ | |
865 | if (ondisk->parent) { | |
8cd0a023 | 866 | parent = cursor->parent; |
fe7678ee MD |
867 | |
868 | KKASSERT(parent != NULL); | |
869 | KKASSERT(parent->node_offset == ondisk->parent); | |
427e5fc6 | 870 | } |
427e5fc6 | 871 | |
8cd0a023 | 872 | /* |
fe7678ee | 873 | * If the leaf becomes empty it must be detached from the parent, |
47197d71 | 874 | * potentially recursing through to the filesystem root. |
195c19a1 MD |
875 | * |
876 | * This may reposition the cursor at one of the parent's of the | |
877 | * current node. | |
6a37e7e4 MD |
878 | * |
879 | * Ignore deadlock errors, that simply means that btree_remove | |
f36a9737 | 880 | * was unable to recurse and had to leave us with an empty leaf. |
8cd0a023 | 881 | */ |
b3deaf57 | 882 | KKASSERT(cursor->index <= ondisk->count); |
8cd0a023 | 883 | if (ondisk->count == 0) { |
f36a9737 | 884 | error = btree_remove(cursor); |
6a37e7e4 MD |
885 | if (error == EDEADLK) |
886 | error = 0; | |
8cd0a023 | 887 | } else { |
8cd0a023 MD |
888 | error = 0; |
889 | } | |
eaeff70d MD |
890 | KKASSERT(cursor->parent == NULL || |
891 | cursor->parent_index < cursor->parent->ondisk->count); | |
8cd0a023 MD |
892 | return(error); |
893 | } | |
427e5fc6 MD |
894 | |
895 | /* | |
8cd0a023 MD |
896 | * PRIMAY B-TREE SEARCH SUPPORT PROCEDURE |
897 | * | |
47197d71 | 898 | * Search the filesystem B-Tree for cursor->key_beg, return the matching node. |
8cd0a023 | 899 | * |
d26d0ae9 MD |
900 | * The search can begin ANYWHERE in the B-Tree. As a first step the search |
901 | * iterates up the tree as necessary to properly position itself prior to | |
902 | * actually doing the sarch. | |
903 | * | |
8cd0a023 | 904 | * INSERTIONS: The search will split full nodes and leaves on its way down |
d26d0ae9 MD |
905 | * and guarentee that the leaf it ends up on is not full. If we run out |
906 | * of space the search continues to the leaf (to position the cursor for | |
907 | * the spike), but ENOSPC is returned. | |
427e5fc6 | 908 | * |
fbc6e32a MD |
909 | * The search is only guarenteed to end up on a leaf if an error code of 0 |
910 | * is returned, or if inserting and an error code of ENOENT is returned. | |
d26d0ae9 | 911 | * Otherwise it can stop at an internal node. On success a search returns |
47197d71 | 912 | * a leaf node. |
eaeff70d MD |
913 | * |
914 | * COMPLEXITY WARNING! This is the core B-Tree search code for the entire | |
915 | * filesystem, and it is not simple code. Please note the following facts: | |
916 | * | |
917 | * - Internal node recursions have a boundary on the left AND right. The | |
9582c7da | 918 | * right boundary is non-inclusive. The create_tid is a generic part |
eaeff70d MD |
919 | * of the key for internal nodes. |
920 | * | |
47197d71 | 921 | * - Leaf nodes contain terminal elements only now. |
eaeff70d MD |
922 | * |
923 | * - Filesystem lookups typically set HAMMER_CURSOR_ASOF, indicating a | |
b33e2cc0 MD |
924 | * historical search. ASOF and INSERT are mutually exclusive. When |
925 | * doing an as-of lookup btree_search() checks for a right-edge boundary | |
9582c7da MD |
926 | * case. If while recursing down the left-edge differs from the key |
927 | * by ONLY its create_tid, HAMMER_CURSOR_CREATE_CHECK is set along | |
928 | * with cursor->create_check. This is used by btree_lookup() to iterate. | |
929 | * The iteration backwards because as-of searches can wind up going | |
b33e2cc0 | 930 | * down the wrong branch of the B-Tree. |
427e5fc6 | 931 | */ |
8cd0a023 | 932 | static |
427e5fc6 | 933 | int |
8cd0a023 | 934 | btree_search(hammer_cursor_t cursor, int flags) |
427e5fc6 | 935 | { |
8cd0a023 | 936 | hammer_node_ondisk_t node; |
61aeeb33 | 937 | hammer_btree_elm_t elm; |
8cd0a023 | 938 | int error; |
d26d0ae9 | 939 | int enospc = 0; |
8cd0a023 MD |
940 | int i; |
941 | int r; | |
b33e2cc0 | 942 | int s; |
8cd0a023 MD |
943 | |
944 | flags |= cursor->flags; | |
cb51be26 | 945 | ++hammer_stats_btree_searches; |
8cd0a023 | 946 | |
b3deaf57 | 947 | if (hammer_debug_btree) { |
2f85fa4d | 948 | kprintf("SEARCH %016llx[%d] %016llx %02x key=%016llx cre=%016llx lo=%02x (td = %p)\n", |
973c11b9 | 949 | (long long)cursor->node->node_offset, |
eaeff70d | 950 | cursor->index, |
973c11b9 | 951 | (long long)cursor->key_beg.obj_id, |
b3deaf57 | 952 | cursor->key_beg.rec_type, |
973c11b9 MD |
953 | (long long)cursor->key_beg.key, |
954 | (long long)cursor->key_beg.create_tid, | |
2f85fa4d | 955 | cursor->key_beg.localization, |
a84a197d | 956 | curthread |
b3deaf57 | 957 | ); |
a84a197d MD |
958 | if (cursor->parent) |
959 | kprintf("SEARCHP %016llx[%d] (%016llx/%016llx %016llx/%016llx) (%p/%p %p/%p)\n", | |
973c11b9 MD |
960 | (long long)cursor->parent->node_offset, |
961 | cursor->parent_index, | |
962 | (long long)cursor->left_bound->obj_id, | |
963 | (long long)cursor->parent->ondisk->elms[cursor->parent_index].internal.base.obj_id, | |
964 | (long long)cursor->right_bound->obj_id, | |
965 | (long long)cursor->parent->ondisk->elms[cursor->parent_index+1].internal.base.obj_id, | |
a84a197d MD |
966 | cursor->left_bound, |
967 | &cursor->parent->ondisk->elms[cursor->parent_index], | |
968 | cursor->right_bound, | |
969 | &cursor->parent->ondisk->elms[cursor->parent_index+1] | |
970 | ); | |
b3deaf57 MD |
971 | } |
972 | ||
8cd0a023 MD |
973 | /* |
974 | * Move our cursor up the tree until we find a node whos range covers | |
47197d71 | 975 | * the key we are trying to locate. |
8cd0a023 MD |
976 | * |
977 | * The left bound is inclusive, the right bound is non-inclusive. | |
47197d71 | 978 | * It is ok to cursor up too far. |
8cd0a023 | 979 | */ |
b33e2cc0 MD |
980 | for (;;) { |
981 | r = hammer_btree_cmp(&cursor->key_beg, cursor->left_bound); | |
982 | s = hammer_btree_cmp(&cursor->key_beg, cursor->right_bound); | |
983 | if (r >= 0 && s < 0) | |
984 | break; | |
9944ae54 | 985 | KKASSERT(cursor->parent); |
cb51be26 | 986 | ++hammer_stats_btree_iterations; |
6a37e7e4 | 987 | error = hammer_cursor_up(cursor); |
8cd0a023 MD |
988 | if (error) |
989 | goto done; | |
427e5fc6 | 990 | } |
427e5fc6 | 991 | |
b33e2cc0 MD |
992 | /* |
993 | * The delete-checks below are based on node, not parent. Set the | |
994 | * initial delete-check based on the parent. | |
995 | */ | |
9582c7da MD |
996 | if (r == 1) { |
997 | KKASSERT(cursor->left_bound->create_tid != 1); | |
998 | cursor->create_check = cursor->left_bound->create_tid - 1; | |
999 | cursor->flags |= HAMMER_CURSOR_CREATE_CHECK; | |
b33e2cc0 MD |
1000 | } |
1001 | ||
8cd0a023 | 1002 | /* |
47197d71 | 1003 | * We better have ended up with a node somewhere. |
8cd0a023 | 1004 | */ |
47197d71 | 1005 | KKASSERT(cursor->node != NULL); |
8cd0a023 MD |
1006 | |
1007 | /* | |
1008 | * If we are inserting we can't start at a full node if the parent | |
1009 | * is also full (because there is no way to split the node), | |
b33e2cc0 | 1010 | * continue running up the tree until the requirement is satisfied |
47197d71 | 1011 | * or we hit the root of the filesystem. |
9582c7da MD |
1012 | * |
1013 | * (If inserting we aren't doing an as-of search so we don't have | |
1014 | * to worry about create_check). | |
8cd0a023 | 1015 | */ |
61aeeb33 | 1016 | while ((flags & HAMMER_CURSOR_INSERT) && enospc == 0) { |
eaeff70d MD |
1017 | if (cursor->node->ondisk->type == HAMMER_BTREE_TYPE_INTERNAL) { |
1018 | if (btree_node_is_full(cursor->node->ondisk) == 0) | |
1019 | break; | |
1020 | } else { | |
47197d71 | 1021 | if (btree_node_is_full(cursor->node->ondisk) ==0) |
eaeff70d MD |
1022 | break; |
1023 | } | |
b33e2cc0 MD |
1024 | if (cursor->node->ondisk->parent == 0 || |
1025 | cursor->parent->ondisk->count != HAMMER_BTREE_INT_ELMS) { | |
8cd0a023 | 1026 | break; |
b33e2cc0 | 1027 | } |
cb51be26 | 1028 | ++hammer_stats_btree_iterations; |
6a37e7e4 | 1029 | error = hammer_cursor_up(cursor); |
47197d71 | 1030 | /* node may have become stale */ |
8cd0a023 MD |
1031 | if (error) |
1032 | goto done; | |
427e5fc6 | 1033 | } |
427e5fc6 | 1034 | |
8cd0a023 MD |
1035 | /* |
1036 | * Push down through internal nodes to locate the requested key. | |
1037 | */ | |
8cd0a023 MD |
1038 | node = cursor->node->ondisk; |
1039 | while (node->type == HAMMER_BTREE_TYPE_INTERNAL) { | |
8cd0a023 MD |
1040 | /* |
1041 | * Scan the node to find the subtree index to push down into. | |
fbc6e32a | 1042 | * We go one-past, then back-up. |
d113fda1 | 1043 | * |
fe7678ee MD |
1044 | * We must proactively remove deleted elements which may |
1045 | * have been left over from a deadlocked btree_remove(). | |
1046 | * | |
eaeff70d | 1047 | * The left and right boundaries are included in the loop |
d5530d22 | 1048 | * in order to detect edge cases. |
9944ae54 | 1049 | * |
9582c7da | 1050 | * If the separator only differs by create_tid (r == 1) |
eaeff70d MD |
1051 | * and we are doing an as-of search, we may end up going |
1052 | * down a branch to the left of the one containing the | |
1053 | * desired key. This requires numerous special cases. | |
8cd0a023 | 1054 | */ |
47637bff | 1055 | ++hammer_stats_btree_iterations; |
46fe7ae1 | 1056 | if (hammer_debug_btree) { |
47197d71 | 1057 | kprintf("SEARCH-I %016llx count=%d\n", |
973c11b9 | 1058 | (long long)cursor->node->node_offset, |
46fe7ae1 MD |
1059 | node->count); |
1060 | } | |
af209b0f MD |
1061 | |
1062 | /* | |
1063 | * Try to shortcut the search before dropping into the | |
1064 | * linear loop. Locate the first node where r <= 1. | |
1065 | */ | |
1066 | i = hammer_btree_search_node(&cursor->key_beg, node); | |
1067 | while (i <= node->count) { | |
cb51be26 | 1068 | ++hammer_stats_btree_elements; |
61aeeb33 MD |
1069 | elm = &node->elms[i]; |
1070 | r = hammer_btree_cmp(&cursor->key_beg, &elm->base); | |
b33e2cc0 MD |
1071 | if (hammer_debug_btree > 2) { |
1072 | kprintf(" IELM %p %d r=%d\n", | |
1073 | &node->elms[i], i, r); | |
1074 | } | |
9582c7da | 1075 | if (r < 0) |
8cd0a023 | 1076 | break; |
9582c7da MD |
1077 | if (r == 1) { |
1078 | KKASSERT(elm->base.create_tid != 1); | |
1079 | cursor->create_check = elm->base.create_tid - 1; | |
1080 | cursor->flags |= HAMMER_CURSOR_CREATE_CHECK; | |
b33e2cc0 | 1081 | } |
af209b0f | 1082 | ++i; |
8cd0a023 | 1083 | } |
eaeff70d | 1084 | if (hammer_debug_btree) { |
46fe7ae1 MD |
1085 | kprintf("SEARCH-I preI=%d/%d r=%d\n", |
1086 | i, node->count, r); | |
eaeff70d | 1087 | } |
8cd0a023 MD |
1088 | |
1089 | /* | |
9944ae54 MD |
1090 | * These cases occur when the parent's idea of the boundary |
1091 | * is wider then the child's idea of the boundary, and | |
1092 | * require special handling. If not inserting we can | |
1093 | * terminate the search early for these cases but the | |
1094 | * child's boundaries cannot be unconditionally modified. | |
8cd0a023 | 1095 | */ |
fbc6e32a | 1096 | if (i == 0) { |
9944ae54 MD |
1097 | /* |
1098 | * If i == 0 the search terminated to the LEFT of the | |
1099 | * left_boundary but to the RIGHT of the parent's left | |
1100 | * boundary. | |
1101 | */ | |
fbc6e32a | 1102 | u_int8_t save; |
d26d0ae9 | 1103 | |
eaeff70d MD |
1104 | elm = &node->elms[0]; |
1105 | ||
1106 | /* | |
1107 | * If we aren't inserting we can stop here. | |
1108 | */ | |
11ad5ade MD |
1109 | if ((flags & (HAMMER_CURSOR_INSERT | |
1110 | HAMMER_CURSOR_PRUNING)) == 0) { | |
fbc6e32a MD |
1111 | cursor->index = 0; |
1112 | return(ENOENT); | |
1113 | } | |
9944ae54 | 1114 | |
d5530d22 MD |
1115 | /* |
1116 | * Correct a left-hand boundary mismatch. | |
6a37e7e4 | 1117 | * |
f36a9737 MD |
1118 | * We can only do this if we can upgrade the lock, |
1119 | * and synchronized as a background cursor (i.e. | |
1120 | * inserting or pruning). | |
10a5d1ba MD |
1121 | * |
1122 | * WARNING: We can only do this if inserting, i.e. | |
1123 | * we are running on the backend. | |
d5530d22 | 1124 | */ |
eaeff70d MD |
1125 | if ((error = hammer_cursor_upgrade(cursor)) != 0) |
1126 | return(error); | |
10a5d1ba | 1127 | KKASSERT(cursor->flags & HAMMER_CURSOR_BACKEND); |
c9b9e29d MD |
1128 | hammer_modify_node_field(cursor->trans, cursor->node, |
1129 | elms[0]); | |
fe7678ee | 1130 | save = node->elms[0].base.btype; |
d5530d22 | 1131 | node->elms[0].base = *cursor->left_bound; |
fe7678ee | 1132 | node->elms[0].base.btype = save; |
10a5d1ba | 1133 | hammer_modify_node_done(cursor->node); |
9944ae54 | 1134 | } else if (i == node->count + 1) { |
d26d0ae9 | 1135 | /* |
9944ae54 MD |
1136 | * If i == node->count + 1 the search terminated to |
1137 | * the RIGHT of the right boundary but to the LEFT | |
eaeff70d MD |
1138 | * of the parent's right boundary. If we aren't |
1139 | * inserting we can stop here. | |
d113fda1 | 1140 | * |
9944ae54 MD |
1141 | * Note that the last element in this case is |
1142 | * elms[i-2] prior to adjustments to 'i'. | |
d26d0ae9 | 1143 | */ |
9944ae54 | 1144 | --i; |
11ad5ade MD |
1145 | if ((flags & (HAMMER_CURSOR_INSERT | |
1146 | HAMMER_CURSOR_PRUNING)) == 0) { | |
9944ae54 | 1147 | cursor->index = i; |
eaeff70d | 1148 | return (ENOENT); |
d26d0ae9 MD |
1149 | } |
1150 | ||
d5530d22 MD |
1151 | /* |
1152 | * Correct a right-hand boundary mismatch. | |
1153 | * (actual push-down record is i-2 prior to | |
1154 | * adjustments to i). | |
6a37e7e4 | 1155 | * |
f36a9737 MD |
1156 | * We can only do this if we can upgrade the lock, |
1157 | * and synchronized as a background cursor (i.e. | |
1158 | * inserting or pruning). | |
10a5d1ba MD |
1159 | * |
1160 | * WARNING: We can only do this if inserting, i.e. | |
1161 | * we are running on the backend. | |
d5530d22 | 1162 | */ |
eaeff70d MD |
1163 | if ((error = hammer_cursor_upgrade(cursor)) != 0) |
1164 | return(error); | |
9944ae54 | 1165 | elm = &node->elms[i]; |
10a5d1ba | 1166 | KKASSERT(cursor->flags & HAMMER_CURSOR_BACKEND); |
36f82b23 MD |
1167 | hammer_modify_node(cursor->trans, cursor->node, |
1168 | &elm->base, sizeof(elm->base)); | |
d5530d22 | 1169 | elm->base = *cursor->right_bound; |
10a5d1ba | 1170 | hammer_modify_node_done(cursor->node); |
d5530d22 | 1171 | --i; |
fbc6e32a MD |
1172 | } else { |
1173 | /* | |
9944ae54 MD |
1174 | * The push-down index is now i - 1. If we had |
1175 | * terminated on the right boundary this will point | |
1176 | * us at the last element. | |
fbc6e32a MD |
1177 | */ |
1178 | --i; | |
1179 | } | |
8cd0a023 | 1180 | cursor->index = i; |
6a37e7e4 | 1181 | elm = &node->elms[i]; |
8cd0a023 | 1182 | |
b3deaf57 | 1183 | if (hammer_debug_btree) { |
47197d71 | 1184 | kprintf("RESULT-I %016llx[%d] %016llx %02x " |
2f85fa4d | 1185 | "key=%016llx cre=%016llx lo=%02x\n", |
973c11b9 | 1186 | (long long)cursor->node->node_offset, |
eaeff70d | 1187 | i, |
973c11b9 | 1188 | (long long)elm->internal.base.obj_id, |
b3deaf57 | 1189 | elm->internal.base.rec_type, |
973c11b9 MD |
1190 | (long long)elm->internal.base.key, |
1191 | (long long)elm->internal.base.create_tid, | |
2f85fa4d | 1192 | elm->internal.base.localization |
b3deaf57 MD |
1193 | ); |
1194 | } | |
1195 | ||
6a37e7e4 | 1196 | /* |
f36a9737 | 1197 | * We better have a valid subtree offset. |
6a37e7e4 | 1198 | */ |
f36a9737 | 1199 | KKASSERT(elm->internal.subtree_offset != 0); |
6a37e7e4 | 1200 | |
8cd0a023 MD |
1201 | /* |
1202 | * Handle insertion and deletion requirements. | |
1203 | * | |
1204 | * If inserting split full nodes. The split code will | |
1205 | * adjust cursor->node and cursor->index if the current | |
1206 | * index winds up in the new node. | |
61aeeb33 | 1207 | * |
9944ae54 MD |
1208 | * If inserting and a left or right edge case was detected, |
1209 | * we cannot correct the left or right boundary and must | |
1210 | * prepend and append an empty leaf node in order to make | |
1211 | * the boundary correction. | |
1212 | * | |
61aeeb33 MD |
1213 | * If we run out of space we set enospc and continue on |
1214 | * to a leaf to provide the spike code with a good point | |
47197d71 | 1215 | * of entry. |
8cd0a023 | 1216 | */ |
61aeeb33 | 1217 | if ((flags & HAMMER_CURSOR_INSERT) && enospc == 0) { |
fe7678ee | 1218 | if (btree_node_is_full(node)) { |
8cd0a023 | 1219 | error = btree_split_internal(cursor); |
d26d0ae9 MD |
1220 | if (error) { |
1221 | if (error != ENOSPC) | |
1222 | goto done; | |
1223 | enospc = 1; | |
d26d0ae9 | 1224 | } |
8cd0a023 MD |
1225 | /* |
1226 | * reload stale pointers | |
1227 | */ | |
1228 | i = cursor->index; | |
1229 | node = cursor->node->ondisk; | |
1230 | } | |
d26d0ae9 | 1231 | } |
427e5fc6 MD |
1232 | |
1233 | /* | |
8cd0a023 | 1234 | * Push down (push into new node, existing node becomes |
d26d0ae9 | 1235 | * the parent) and continue the search. |
427e5fc6 | 1236 | */ |
8cd0a023 | 1237 | error = hammer_cursor_down(cursor); |
47197d71 | 1238 | /* node may have become stale */ |
8cd0a023 MD |
1239 | if (error) |
1240 | goto done; | |
1241 | node = cursor->node->ondisk; | |
427e5fc6 | 1242 | } |
427e5fc6 | 1243 | |
8cd0a023 MD |
1244 | /* |
1245 | * We are at a leaf, do a linear search of the key array. | |
d26d0ae9 MD |
1246 | * |
1247 | * On success the index is set to the matching element and 0 | |
1248 | * is returned. | |
1249 | * | |
1250 | * On failure the index is set to the insertion point and ENOENT | |
1251 | * is returned. | |
8cd0a023 MD |
1252 | * |
1253 | * Boundaries are not stored in leaf nodes, so the index can wind | |
1254 | * up to the left of element 0 (index == 0) or past the end of | |
f36a9737 MD |
1255 | * the array (index == node->count). It is also possible that the |
1256 | * leaf might be empty. | |
8cd0a023 | 1257 | */ |
47637bff | 1258 | ++hammer_stats_btree_iterations; |
fe7678ee | 1259 | KKASSERT (node->type == HAMMER_BTREE_TYPE_LEAF); |
8cd0a023 | 1260 | KKASSERT(node->count <= HAMMER_BTREE_LEAF_ELMS); |
46fe7ae1 | 1261 | if (hammer_debug_btree) { |
47197d71 | 1262 | kprintf("SEARCH-L %016llx count=%d\n", |
973c11b9 | 1263 | (long long)cursor->node->node_offset, |
46fe7ae1 MD |
1264 | node->count); |
1265 | } | |
8cd0a023 | 1266 | |
af209b0f MD |
1267 | /* |
1268 | * Try to shortcut the search before dropping into the | |
1269 | * linear loop. Locate the first node where r <= 1. | |
1270 | */ | |
1271 | i = hammer_btree_search_node(&cursor->key_beg, node); | |
1272 | while (i < node->count) { | |
cb51be26 | 1273 | ++hammer_stats_btree_elements; |
fe7678ee MD |
1274 | elm = &node->elms[i]; |
1275 | ||
1276 | r = hammer_btree_cmp(&cursor->key_beg, &elm->leaf.base); | |
427e5fc6 | 1277 | |
d5530d22 MD |
1278 | if (hammer_debug_btree > 1) |
1279 | kprintf(" ELM %p %d r=%d\n", &node->elms[i], i, r); | |
1280 | ||
427e5fc6 | 1281 | /* |
fe7678ee | 1282 | * We are at a record element. Stop if we've flipped past |
9582c7da MD |
1283 | * key_beg, not counting the create_tid test. Allow the |
1284 | * r == 1 case (key_beg > element but differs only by its | |
1285 | * create_tid) to fall through to the AS-OF check. | |
427e5fc6 | 1286 | */ |
fe7678ee MD |
1287 | KKASSERT (elm->leaf.base.btype == HAMMER_BTREE_TYPE_RECORD); |
1288 | ||
9582c7da | 1289 | if (r < 0) |
d5530d22 | 1290 | goto failed; |
af209b0f MD |
1291 | if (r > 1) { |
1292 | ++i; | |
d5530d22 | 1293 | continue; |
af209b0f | 1294 | } |
427e5fc6 | 1295 | |
66325755 | 1296 | /* |
9582c7da | 1297 | * Check our as-of timestamp against the element. |
66325755 | 1298 | */ |
eaeff70d | 1299 | if (flags & HAMMER_CURSOR_ASOF) { |
fe7678ee | 1300 | if (hammer_btree_chkts(cursor->asof, |
d113fda1 | 1301 | &node->elms[i].base) != 0) { |
af209b0f | 1302 | ++i; |
d113fda1 MD |
1303 | continue; |
1304 | } | |
eaeff70d MD |
1305 | /* success */ |
1306 | } else { | |
af209b0f MD |
1307 | if (r > 0) { /* can only be +1 */ |
1308 | ++i; | |
9582c7da | 1309 | continue; |
af209b0f | 1310 | } |
eaeff70d | 1311 | /* success */ |
66325755 | 1312 | } |
d5530d22 MD |
1313 | cursor->index = i; |
1314 | error = 0; | |
eaeff70d | 1315 | if (hammer_debug_btree) { |
47197d71 | 1316 | kprintf("RESULT-L %016llx[%d] (SUCCESS)\n", |
973c11b9 | 1317 | (long long)cursor->node->node_offset, i); |
eaeff70d | 1318 | } |
d5530d22 MD |
1319 | goto done; |
1320 | } | |
1321 | ||
1322 | /* | |
eaeff70d | 1323 | * The search of the leaf node failed. i is the insertion point. |
d5530d22 | 1324 | */ |
d5530d22 | 1325 | failed: |
b3deaf57 | 1326 | if (hammer_debug_btree) { |
47197d71 | 1327 | kprintf("RESULT-L %016llx[%d] (FAILED)\n", |
973c11b9 | 1328 | (long long)cursor->node->node_offset, i); |
b3deaf57 MD |
1329 | } |
1330 | ||
8cd0a023 MD |
1331 | /* |
1332 | * No exact match was found, i is now at the insertion point. | |
1333 | * | |
1334 | * If inserting split a full leaf before returning. This | |
1335 | * may have the side effect of adjusting cursor->node and | |
1336 | * cursor->index. | |
1337 | */ | |
1338 | cursor->index = i; | |
eaeff70d | 1339 | if ((flags & HAMMER_CURSOR_INSERT) && enospc == 0 && |
47197d71 | 1340 | btree_node_is_full(node)) { |
8cd0a023 | 1341 | error = btree_split_leaf(cursor); |
d26d0ae9 MD |
1342 | if (error) { |
1343 | if (error != ENOSPC) | |
1344 | goto done; | |
1345 | enospc = 1; | |
d26d0ae9 MD |
1346 | } |
1347 | /* | |
1348 | * reload stale pointers | |
1349 | */ | |
8cd0a023 MD |
1350 | /* NOT USED |
1351 | i = cursor->index; | |
1352 | node = &cursor->node->internal; | |
1353 | */ | |
8cd0a023 | 1354 | } |
d26d0ae9 MD |
1355 | |
1356 | /* | |
1357 | * We reached a leaf but did not find the key we were looking for. | |
1358 | * If this is an insert we will be properly positioned for an insert | |
1359 | * (ENOENT) or spike (ENOSPC) operation. | |
1360 | */ | |
1361 | error = enospc ? ENOSPC : ENOENT; | |
8cd0a023 | 1362 | done: |
427e5fc6 MD |
1363 | return(error); |
1364 | } | |
1365 | ||
af209b0f MD |
1366 | /* |
1367 | * Heuristical search for the first element whos comparison is <= 1. May | |
1368 | * return an index whos compare result is > 1 but may only return an index | |
1369 | * whos compare result is <= 1 if it is the first element with that result. | |
1370 | */ | |
bcac4bbb | 1371 | int |
af209b0f MD |
1372 | hammer_btree_search_node(hammer_base_elm_t elm, hammer_node_ondisk_t node) |
1373 | { | |
1374 | int b; | |
1375 | int s; | |
1376 | int i; | |
1377 | int r; | |
1378 | ||
1379 | /* | |
1380 | * Don't bother if the node does not have very many elements | |
1381 | */ | |
1382 | b = 0; | |
1383 | s = node->count; | |
1384 | while (s - b > 4) { | |
1385 | i = b + (s - b) / 2; | |
cb51be26 | 1386 | ++hammer_stats_btree_elements; |
af209b0f MD |
1387 | r = hammer_btree_cmp(elm, &node->elms[i].leaf.base); |
1388 | if (r <= 1) { | |
1389 | s = i; | |
1390 | } else { | |
1391 | b = i; | |
1392 | } | |
1393 | } | |
1394 | return(b); | |
1395 | } | |
1396 | ||
8cd0a023 | 1397 | |
427e5fc6 | 1398 | /************************************************************************ |
8cd0a023 | 1399 | * SPLITTING AND MERGING * |
427e5fc6 MD |
1400 | ************************************************************************ |
1401 | * | |
1402 | * These routines do all the dirty work required to split and merge nodes. | |
1403 | */ | |
1404 | ||
1405 | /* | |
8cd0a023 | 1406 | * Split an internal node into two nodes and move the separator at the split |
fe7678ee | 1407 | * point to the parent. |
427e5fc6 | 1408 | * |
8cd0a023 MD |
1409 | * (cursor->node, cursor->index) indicates the element the caller intends |
1410 | * to push into. We will adjust node and index if that element winds | |
427e5fc6 | 1411 | * up in the split node. |
8cd0a023 | 1412 | * |
47197d71 MD |
1413 | * If we are at the root of the filesystem a new root must be created with |
1414 | * two elements, one pointing to the original root and one pointing to the | |
8cd0a023 | 1415 | * newly allocated split node. |
427e5fc6 MD |
1416 | */ |
1417 | static | |
1418 | int | |
8cd0a023 | 1419 | btree_split_internal(hammer_cursor_t cursor) |
427e5fc6 | 1420 | { |
8cd0a023 MD |
1421 | hammer_node_ondisk_t ondisk; |
1422 | hammer_node_t node; | |
1423 | hammer_node_t parent; | |
1424 | hammer_node_t new_node; | |
1425 | hammer_btree_elm_t elm; | |
1426 | hammer_btree_elm_t parent_elm; | |
1775b6a0 | 1427 | struct hammer_node_lock lockroot; |
36f82b23 | 1428 | hammer_mount_t hmp = cursor->trans->hmp; |
df2ccbac | 1429 | hammer_off_t hint; |
427e5fc6 MD |
1430 | int parent_index; |
1431 | int made_root; | |
1432 | int split; | |
1433 | int error; | |
7f7c1f84 | 1434 | int i; |
8cd0a023 | 1435 | const int esize = sizeof(*elm); |
427e5fc6 | 1436 | |
1775b6a0 MD |
1437 | hammer_node_lock_init(&lockroot, cursor->node); |
1438 | error = hammer_btree_lock_children(cursor, 1, &lockroot); | |
47197d71 MD |
1439 | if (error) |
1440 | goto done; | |
7bc5b8c2 MD |
1441 | if ((error = hammer_cursor_upgrade(cursor)) != 0) |
1442 | goto done; | |
cb51be26 | 1443 | ++hammer_stats_btree_splits; |
6a37e7e4 | 1444 | |
427e5fc6 MD |
1445 | /* |
1446 | * We are splitting but elms[split] will be promoted to the parent, | |
1447 | * leaving the right hand node with one less element. If the | |
1448 | * insertion point will be on the left-hand side adjust the split | |
1449 | * point to give the right hand side one additional node. | |
1450 | */ | |
8cd0a023 MD |
1451 | node = cursor->node; |
1452 | ondisk = node->ondisk; | |
1453 | split = (ondisk->count + 1) / 2; | |
427e5fc6 MD |
1454 | if (cursor->index <= split) |
1455 | --split; | |
427e5fc6 MD |
1456 | |
1457 | /* | |
47197d71 MD |
1458 | * If we are at the root of the filesystem, create a new root node |
1459 | * with 1 element and split normally. Avoid making major | |
1460 | * modifications until we know the whole operation will work. | |
427e5fc6 | 1461 | */ |
8cd0a023 | 1462 | if (ondisk->parent == 0) { |
df2ccbac MD |
1463 | parent = hammer_alloc_btree(cursor->trans, node->node_offset, |
1464 | &error); | |
427e5fc6 | 1465 | if (parent == NULL) |
6a37e7e4 | 1466 | goto done; |
8cd0a023 | 1467 | hammer_lock_ex(&parent->lock); |
36f82b23 | 1468 | hammer_modify_node_noundo(cursor->trans, parent); |
8cd0a023 MD |
1469 | ondisk = parent->ondisk; |
1470 | ondisk->count = 1; | |
1471 | ondisk->parent = 0; | |
a56cb012 | 1472 | ondisk->mirror_tid = node->ondisk->mirror_tid; |
8cd0a023 | 1473 | ondisk->type = HAMMER_BTREE_TYPE_INTERNAL; |
47197d71 | 1474 | ondisk->elms[0].base = hmp->root_btree_beg; |
fe7678ee | 1475 | ondisk->elms[0].base.btype = node->ondisk->type; |
8cd0a023 | 1476 | ondisk->elms[0].internal.subtree_offset = node->node_offset; |
47197d71 | 1477 | ondisk->elms[1].base = hmp->root_btree_end; |
10a5d1ba | 1478 | hammer_modify_node_done(parent); |
fe7678ee | 1479 | /* ondisk->elms[1].base.btype - not used */ |
427e5fc6 | 1480 | made_root = 1; |
8cd0a023 | 1481 | parent_index = 0; /* index of current node in parent */ |
427e5fc6 MD |
1482 | } else { |
1483 | made_root = 0; | |
8cd0a023 MD |
1484 | parent = cursor->parent; |
1485 | parent_index = cursor->parent_index; | |
427e5fc6 | 1486 | } |
427e5fc6 | 1487 | |
df2ccbac MD |
1488 | /* |
1489 | * Calculate a hint for the allocation of the new B-Tree node. | |
1490 | * The most likely expansion is coming from the insertion point | |
1491 | * at cursor->index, so try to localize the allocation of our | |
1492 | * new node to accomodate that sub-tree. | |
1493 | * | |
1494 | * Use the right-most sub-tree when expandinging on the right edge. | |
1495 | * This is a very common case when copying a directory tree. | |
1496 | */ | |
1497 | if (cursor->index == ondisk->count) | |
1498 | hint = ondisk->elms[cursor->index - 1].internal.subtree_offset; | |
1499 | else | |
1500 | hint = ondisk->elms[cursor->index].internal.subtree_offset; | |
1501 | ||
427e5fc6 MD |
1502 | /* |
1503 | * Split node into new_node at the split point. | |
1504 | * | |
df2ccbac | 1505 | * B O O O P N N B <-- P = node->elms[split] (index 4) |
427e5fc6 MD |
1506 | * 0 1 2 3 4 5 6 <-- subtree indices |
1507 | * | |
1508 | * x x P x x | |
1509 | * s S S s | |
1510 | * / \ | |
1511 | * B O O O B B N N B <--- inner boundary points are 'P' | |
1512 | * 0 1 2 3 4 5 6 | |
427e5fc6 | 1513 | */ |
df2ccbac | 1514 | new_node = hammer_alloc_btree(cursor->trans, hint, &error); |
427e5fc6 | 1515 | if (new_node == NULL) { |
8cd0a023 MD |
1516 | if (made_root) { |
1517 | hammer_unlock(&parent->lock); | |
36f82b23 | 1518 | hammer_delete_node(cursor->trans, parent); |
8cd0a023 MD |
1519 | hammer_rel_node(parent); |
1520 | } | |
6a37e7e4 | 1521 | goto done; |
427e5fc6 | 1522 | } |
8cd0a023 | 1523 | hammer_lock_ex(&new_node->lock); |
427e5fc6 MD |
1524 | |
1525 | /* | |
8cd0a023 | 1526 | * Create the new node. P becomes the left-hand boundary in the |
427e5fc6 MD |
1527 | * new node. Copy the right-hand boundary as well. |
1528 | * | |
1529 | * elm is the new separator. | |
1530 | */ | |
36f82b23 MD |
1531 | hammer_modify_node_noundo(cursor->trans, new_node); |
1532 | hammer_modify_node_all(cursor->trans, node); | |
8cd0a023 MD |
1533 | ondisk = node->ondisk; |
1534 | elm = &ondisk->elms[split]; | |
1535 | bcopy(elm, &new_node->ondisk->elms[0], | |
1536 | (ondisk->count - split + 1) * esize); | |
1537 | new_node->ondisk->count = ondisk->count - split; | |
1538 | new_node->ondisk->parent = parent->node_offset; | |
1539 | new_node->ondisk->type = HAMMER_BTREE_TYPE_INTERNAL; | |
a56cb012 | 1540 | new_node->ondisk->mirror_tid = ondisk->mirror_tid; |
8cd0a023 | 1541 | KKASSERT(ondisk->type == new_node->ondisk->type); |
b3bad96f | 1542 | hammer_cursor_split_node(node, new_node, split); |
427e5fc6 MD |
1543 | |
1544 | /* | |
fe7678ee MD |
1545 | * Cleanup the original node. Elm (P) becomes the new boundary, |
1546 | * its subtree_offset was moved to the new node. If we had created | |
427e5fc6 MD |
1547 | * a new root its parent pointer may have changed. |
1548 | */ | |
8cd0a023 | 1549 | elm->internal.subtree_offset = 0; |
c0ade690 | 1550 | ondisk->count = split; |
427e5fc6 MD |
1551 | |
1552 | /* | |
1553 | * Insert the separator into the parent, fixup the parent's | |
1554 | * reference to the original node, and reference the new node. | |
1555 | * The separator is P. | |
1556 | * | |
1557 | * Remember that base.count does not include the right-hand boundary. | |
1558 | */ | |
36f82b23 | 1559 | hammer_modify_node_all(cursor->trans, parent); |
8cd0a023 | 1560 | ondisk = parent->ondisk; |
d26d0ae9 | 1561 | KKASSERT(ondisk->count != HAMMER_BTREE_INT_ELMS); |
8cd0a023 | 1562 | parent_elm = &ondisk->elms[parent_index+1]; |
427e5fc6 | 1563 | bcopy(parent_elm, parent_elm + 1, |
8cd0a023 MD |
1564 | (ondisk->count - parent_index) * esize); |
1565 | parent_elm->internal.base = elm->base; /* separator P */ | |
fe7678ee | 1566 | parent_elm->internal.base.btype = new_node->ondisk->type; |
8cd0a023 | 1567 | parent_elm->internal.subtree_offset = new_node->node_offset; |
a56cb012 | 1568 | parent_elm->internal.mirror_tid = new_node->ondisk->mirror_tid; |
76376933 | 1569 | ++ondisk->count; |
10a5d1ba | 1570 | hammer_modify_node_done(parent); |
b3bad96f | 1571 | hammer_cursor_inserted_element(parent, parent_index + 1); |
427e5fc6 | 1572 | |
7f7c1f84 MD |
1573 | /* |
1574 | * The children of new_node need their parent pointer set to new_node. | |
b33e2cc0 MD |
1575 | * The children have already been locked by |
1576 | * hammer_btree_lock_children(). | |
7f7c1f84 MD |
1577 | */ |
1578 | for (i = 0; i < new_node->ondisk->count; ++i) { | |
1579 | elm = &new_node->ondisk->elms[i]; | |
36f82b23 | 1580 | error = btree_set_parent(cursor->trans, new_node, elm); |
7f7c1f84 MD |
1581 | if (error) { |
1582 | panic("btree_split_internal: btree-fixup problem"); | |
1583 | } | |
1584 | } | |
10a5d1ba | 1585 | hammer_modify_node_done(new_node); |
7f7c1f84 | 1586 | |
427e5fc6 | 1587 | /* |
47197d71 | 1588 | * The filesystem's root B-Tree pointer may have to be updated. |
427e5fc6 MD |
1589 | */ |
1590 | if (made_root) { | |
47197d71 MD |
1591 | hammer_volume_t volume; |
1592 | ||
1593 | volume = hammer_get_root_volume(hmp, &error); | |
1594 | KKASSERT(error == 0); | |
1595 | ||
e8599db1 MD |
1596 | hammer_modify_volume_field(cursor->trans, volume, |
1597 | vol0_btree_root); | |
47197d71 | 1598 | volume->ondisk->vol0_btree_root = parent->node_offset; |
10a5d1ba | 1599 | hammer_modify_volume_done(volume); |
8cd0a023 MD |
1600 | node->ondisk->parent = parent->node_offset; |
1601 | if (cursor->parent) { | |
1602 | hammer_unlock(&cursor->parent->lock); | |
1603 | hammer_rel_node(cursor->parent); | |
1604 | } | |
1605 | cursor->parent = parent; /* lock'd and ref'd */ | |
47197d71 | 1606 | hammer_rel_volume(volume, 0); |
427e5fc6 | 1607 | } |
10a5d1ba | 1608 | hammer_modify_node_done(node); |
427e5fc6 MD |
1609 | |
1610 | /* | |
1611 | * Ok, now adjust the cursor depending on which element the original | |
1612 | * index was pointing at. If we are >= the split point the push node | |
1613 | * is now in the new node. | |
1614 | * | |
1615 | * NOTE: If we are at the split point itself we cannot stay with the | |
1616 | * original node because the push index will point at the right-hand | |
1617 | * boundary, which is illegal. | |
8cd0a023 MD |
1618 | * |
1619 | * NOTE: The cursor's parent or parent_index must be adjusted for | |
1620 | * the case where a new parent (new root) was created, and the case | |
1621 | * where the cursor is now pointing at the split node. | |
427e5fc6 MD |
1622 | */ |
1623 | if (cursor->index >= split) { | |
8cd0a023 | 1624 | cursor->parent_index = parent_index + 1; |
427e5fc6 | 1625 | cursor->index -= split; |
8cd0a023 MD |
1626 | hammer_unlock(&cursor->node->lock); |
1627 | hammer_rel_node(cursor->node); | |
1628 | cursor->node = new_node; /* locked and ref'd */ | |
1629 | } else { | |
1630 | cursor->parent_index = parent_index; | |
1631 | hammer_unlock(&new_node->lock); | |
1632 | hammer_rel_node(new_node); | |
427e5fc6 | 1633 | } |
76376933 MD |
1634 | |
1635 | /* | |
1636 | * Fixup left and right bounds | |
1637 | */ | |
1638 | parent_elm = &parent->ondisk->elms[cursor->parent_index]; | |
fbc6e32a MD |
1639 | cursor->left_bound = &parent_elm[0].internal.base; |
1640 | cursor->right_bound = &parent_elm[1].internal.base; | |
b3deaf57 MD |
1641 | KKASSERT(hammer_btree_cmp(cursor->left_bound, |
1642 | &cursor->node->ondisk->elms[0].internal.base) <= 0); | |
1643 | KKASSERT(hammer_btree_cmp(cursor->right_bound, | |
9944ae54 | 1644 | &cursor->node->ondisk->elms[cursor->node->ondisk->count].internal.base) >= 0); |
76376933 | 1645 | |
6a37e7e4 | 1646 | done: |
1775b6a0 | 1647 | hammer_btree_unlock_children(cursor, &lockroot); |
6a37e7e4 MD |
1648 | hammer_cursor_downgrade(cursor); |
1649 | return (error); | |
427e5fc6 MD |
1650 | } |
1651 | ||
1652 | /* | |
1653 | * Same as the above, but splits a full leaf node. | |
6a37e7e4 MD |
1654 | * |
1655 | * This function | |
427e5fc6 MD |
1656 | */ |
1657 | static | |
1658 | int | |
8cd0a023 | 1659 | btree_split_leaf(hammer_cursor_t cursor) |
427e5fc6 | 1660 | { |
8cd0a023 MD |
1661 | hammer_node_ondisk_t ondisk; |
1662 | hammer_node_t parent; | |
1663 | hammer_node_t leaf; | |
47197d71 | 1664 | hammer_mount_t hmp; |
8cd0a023 MD |
1665 | hammer_node_t new_leaf; |
1666 | hammer_btree_elm_t elm; | |
1667 | hammer_btree_elm_t parent_elm; | |
b3deaf57 | 1668 | hammer_base_elm_t mid_boundary; |
df2ccbac | 1669 | hammer_off_t hint; |
427e5fc6 MD |
1670 | int parent_index; |
1671 | int made_root; | |
1672 | int split; | |
1673 | int error; | |
8cd0a023 | 1674 | const size_t esize = sizeof(*elm); |
427e5fc6 | 1675 | |
6a37e7e4 MD |
1676 | if ((error = hammer_cursor_upgrade(cursor)) != 0) |
1677 | return(error); | |
cb51be26 | 1678 | ++hammer_stats_btree_splits; |
6a37e7e4 | 1679 | |
36f82b23 MD |
1680 | KKASSERT(hammer_btree_cmp(cursor->left_bound, |
1681 | &cursor->node->ondisk->elms[0].leaf.base) <= 0); | |
1682 | KKASSERT(hammer_btree_cmp(cursor->right_bound, | |
1683 | &cursor->node->ondisk->elms[cursor->node->ondisk->count-1].leaf.base) > 0); | |
1684 | ||
427e5fc6 | 1685 | /* |
8cd0a023 MD |
1686 | * Calculate the split point. If the insertion point will be on |
1687 | * the left-hand side adjust the split point to give the right | |
1688 | * hand side one additional node. | |
fe7678ee MD |
1689 | * |
1690 | * Spikes are made up of two leaf elements which cannot be | |
1691 | * safely split. | |
427e5fc6 | 1692 | */ |
8cd0a023 MD |
1693 | leaf = cursor->node; |
1694 | ondisk = leaf->ondisk; | |
1695 | split = (ondisk->count + 1) / 2; | |
427e5fc6 MD |
1696 | if (cursor->index <= split) |
1697 | --split; | |
1698 | error = 0; | |
40043e7f | 1699 | hmp = leaf->hmp; |
427e5fc6 | 1700 | |
fe7678ee | 1701 | elm = &ondisk->elms[split]; |
fe7678ee | 1702 | |
36f82b23 MD |
1703 | KKASSERT(hammer_btree_cmp(cursor->left_bound, &elm[-1].leaf.base) <= 0); |
1704 | KKASSERT(hammer_btree_cmp(cursor->left_bound, &elm->leaf.base) <= 0); | |
1705 | KKASSERT(hammer_btree_cmp(cursor->right_bound, &elm->leaf.base) > 0); | |
1706 | KKASSERT(hammer_btree_cmp(cursor->right_bound, &elm[1].leaf.base) > 0); | |
1707 | ||
427e5fc6 MD |
1708 | /* |
1709 | * If we are at the root of the tree, create a new root node with | |
1710 | * 1 element and split normally. Avoid making major modifications | |
1711 | * until we know the whole operation will work. | |
1712 | */ | |
8cd0a023 | 1713 | if (ondisk->parent == 0) { |
df2ccbac MD |
1714 | parent = hammer_alloc_btree(cursor->trans, leaf->node_offset, |
1715 | &error); | |
427e5fc6 | 1716 | if (parent == NULL) |
6a37e7e4 | 1717 | goto done; |
8cd0a023 | 1718 | hammer_lock_ex(&parent->lock); |
36f82b23 | 1719 | hammer_modify_node_noundo(cursor->trans, parent); |
8cd0a023 MD |
1720 | ondisk = parent->ondisk; |
1721 | ondisk->count = 1; | |
1722 | ondisk->parent = 0; | |
a56cb012 | 1723 | ondisk->mirror_tid = leaf->ondisk->mirror_tid; |
8cd0a023 | 1724 | ondisk->type = HAMMER_BTREE_TYPE_INTERNAL; |
47197d71 | 1725 | ondisk->elms[0].base = hmp->root_btree_beg; |
fe7678ee | 1726 | ondisk->elms[0].base.btype = leaf->ondisk->type; |
8cd0a023 | 1727 | ondisk->elms[0].internal.subtree_offset = leaf->node_offset; |
47197d71 | 1728 | ondisk->elms[1].base = hmp->root_btree_end; |
fe7678ee | 1729 | /* ondisk->elms[1].base.btype = not used */ |
10a5d1ba | 1730 | hammer_modify_node_done(parent); |
427e5fc6 | 1731 | made_root = 1; |
8cd0a023 | 1732 | parent_index = 0; /* insertion point in parent */ |
427e5fc6 MD |
1733 | } else { |
1734 | made_root = 0; | |
8cd0a023 MD |
1735 | parent = cursor->parent; |
1736 | parent_index = cursor->parent_index; | |
427e5fc6 | 1737 | } |
427e5fc6 | 1738 | |
df2ccbac MD |
1739 | /* |
1740 | * Calculate a hint for the allocation of the new B-Tree leaf node. | |
1741 | * For now just try to localize it within the same bigblock as | |
1742 | * the current leaf. | |
1743 | * | |
1744 | * If the insertion point is at the end of the leaf we recognize a | |
1745 | * likely append sequence of some sort (data, meta-data, inodes, | |
1746 | * whatever). Set the hint to zero to allocate out of linear space | |
1747 | * instead of trying to completely fill previously hinted space. | |
1748 | * | |
1749 | * This also sets the stage for recursive splits to localize using | |
1750 | * the new space. | |
1751 | */ | |
1752 | ondisk = leaf->ondisk; | |
1753 | if (cursor->index == ondisk->count) | |
1754 | hint = 0; | |
1755 | else | |
1756 | hint = leaf->node_offset; | |
1757 | ||
427e5fc6 MD |
1758 | /* |
1759 | * Split leaf into new_leaf at the split point. Select a separator | |
1760 | * value in-between the two leafs but with a bent towards the right | |
1761 | * leaf since comparisons use an 'elm >= separator' inequality. | |
1762 | * | |
1763 | * L L L L L L L L | |
1764 | * | |
1765 | * x x P x x | |
1766 | * s S S s | |
1767 | * / \ | |
1768 | * L L L L L L L L | |
1769 | */ | |
df2ccbac | 1770 | new_leaf = hammer_alloc_btree(cursor->trans, hint, &error); |
427e5fc6 | 1771 | if (new_leaf == NULL) { |
8cd0a023 MD |
1772 | if (made_root) { |
1773 | hammer_unlock(&parent->lock); | |
36f82b23 | 1774 | hammer_delete_node(cursor->trans, parent); |
8cd0a023 MD |
1775 | hammer_rel_node(parent); |
1776 | } | |
6a37e7e4 | 1777 | goto done; |
427e5fc6 | 1778 | } |
8cd0a023 | 1779 | hammer_lock_ex(&new_leaf->lock); |
427e5fc6 MD |
1780 | |
1781 | /* | |
36f82b23 MD |
1782 | * Create the new node and copy the leaf elements from the split |
1783 | * point on to the new node. | |
427e5fc6 | 1784 | */ |
36f82b23 MD |
1785 | hammer_modify_node_all(cursor->trans, leaf); |
1786 | hammer_modify_node_noundo(cursor->trans, new_leaf); | |
8cd0a023 MD |
1787 | ondisk = leaf->ondisk; |
1788 | elm = &ondisk->elms[split]; | |
1789 | bcopy(elm, &new_leaf->ondisk->elms[0], (ondisk->count - split) * esize); | |
1790 | new_leaf->ondisk->count = ondisk->count - split; | |
1791 | new_leaf->ondisk->parent = parent->node_offset; | |
1792 | new_leaf->ondisk->type = HAMMER_BTREE_TYPE_LEAF; | |
a56cb012 | 1793 | new_leaf->ondisk->mirror_tid = ondisk->mirror_tid; |
8cd0a023 | 1794 | KKASSERT(ondisk->type == new_leaf->ondisk->type); |
10a5d1ba | 1795 | hammer_modify_node_done(new_leaf); |
b3bad96f | 1796 | hammer_cursor_split_node(leaf, new_leaf, split); |
427e5fc6 MD |
1797 | |
1798 | /* | |
8cd0a023 MD |
1799 | * Cleanup the original node. Because this is a leaf node and |
1800 | * leaf nodes do not have a right-hand boundary, there | |
c0ade690 MD |
1801 | * aren't any special edge cases to clean up. We just fixup the |
1802 | * count. | |
427e5fc6 | 1803 | */ |
c0ade690 | 1804 | ondisk->count = split; |
427e5fc6 MD |
1805 | |
1806 | /* | |
1807 | * Insert the separator into the parent, fixup the parent's | |
1808 | * reference to the original node, and reference the new node. | |
1809 | * The separator is P. | |
1810 | * | |
1811 | * Remember that base.count does not include the right-hand boundary. | |
1812 | * We are copying parent_index+1 to parent_index+2, not +0 to +1. | |
1813 | */ | |
36f82b23 | 1814 | hammer_modify_node_all(cursor->trans, parent); |
8cd0a023 | 1815 | ondisk = parent->ondisk; |
36f82b23 | 1816 | KKASSERT(split != 0); |
d26d0ae9 | 1817 | KKASSERT(ondisk->count != HAMMER_BTREE_INT_ELMS); |
8cd0a023 | 1818 | parent_elm = &ondisk->elms[parent_index+1]; |
d26d0ae9 MD |
1819 | bcopy(parent_elm, parent_elm + 1, |
1820 | (ondisk->count - parent_index) * esize); | |
eaeff70d | 1821 | |
47197d71 | 1822 | hammer_make_separator(&elm[-1].base, &elm[0].base, &parent_elm->base); |
fe7678ee | 1823 | parent_elm->internal.base.btype = new_leaf->ondisk->type; |
8cd0a023 | 1824 | parent_elm->internal.subtree_offset = new_leaf->node_offset; |
a56cb012 | 1825 | parent_elm->internal.mirror_tid = new_leaf->ondisk->mirror_tid; |
b3deaf57 | 1826 | mid_boundary = &parent_elm->base; |
76376933 | 1827 | ++ondisk->count; |
10a5d1ba | 1828 | hammer_modify_node_done(parent); |
b3bad96f | 1829 | hammer_cursor_inserted_element(parent, parent_index + 1); |
427e5fc6 | 1830 | |
fe7678ee | 1831 | /* |
47197d71 | 1832 | * The filesystem's root B-Tree pointer may have to be updated. |
427e5fc6 MD |
1833 | */ |
1834 | if (made_root) { | |
47197d71 MD |
1835 | hammer_volume_t volume; |
1836 | ||
1837 | volume = hammer_get_root_volume(hmp, &error); | |
1838 | KKASSERT(error == 0); | |
1839 | ||
e8599db1 MD |
1840 | hammer_modify_volume_field(cursor->trans, volume, |
1841 | vol0_btree_root); | |
47197d71 | 1842 | volume->ondisk->vol0_btree_root = parent->node_offset; |
10a5d1ba | 1843 | hammer_modify_volume_done(volume); |
8cd0a023 MD |
1844 | leaf->ondisk->parent = parent->node_offset; |
1845 | if (cursor->parent) { | |
1846 | hammer_unlock(&cursor->parent->lock); | |
1847 | hammer_rel_node(cursor->parent); | |
1848 | } | |
1849 | cursor->parent = parent; /* lock'd and ref'd */ | |
47197d71 | 1850 | hammer_rel_volume(volume, 0); |
427e5fc6 | 1851 | } |
10a5d1ba | 1852 | hammer_modify_node_done(leaf); |
8cd0a023 | 1853 | |
427e5fc6 MD |
1854 | /* |
1855 | * Ok, now adjust the cursor depending on which element the original | |
1856 | * index was pointing at. If we are >= the split point the push node | |
1857 | * is now in the new node. | |
1858 | * | |
b3deaf57 MD |
1859 | * NOTE: If we are at the split point itself we need to select the |
1860 | * old or new node based on where key_beg's insertion point will be. | |
1861 | * If we pick the wrong side the inserted element will wind up in | |
1862 | * the wrong leaf node and outside that node's bounds. | |
427e5fc6 | 1863 | */ |
b3deaf57 MD |
1864 | if (cursor->index > split || |
1865 | (cursor->index == split && | |
1866 | hammer_btree_cmp(&cursor->key_beg, mid_boundary) >= 0)) { | |
8cd0a023 | 1867 | cursor->parent_index = parent_index + 1; |
427e5fc6 | 1868 | cursor->index -= split; |
8cd0a023 MD |
1869 | hammer_unlock(&cursor->node->lock); |
1870 | hammer_rel_node(cursor->node); | |
1871 | cursor->node = new_leaf; | |
1872 | } else { | |
1873 | cursor->parent_index = parent_index; | |
1874 | hammer_unlock(&new_leaf->lock); | |
1875 | hammer_rel_node(new_leaf); | |
427e5fc6 | 1876 | } |
76376933 MD |
1877 | |
1878 | /* | |
1879 | * Fixup left and right bounds | |
1880 | */ | |
1881 | parent_elm = &parent->ondisk->elms[cursor->parent_index]; | |
fbc6e32a MD |
1882 | cursor->left_bound = &parent_elm[0].internal.base; |
1883 | cursor->right_bound = &parent_elm[1].internal.base; | |
eaeff70d MD |
1884 | |
1885 | /* | |
47197d71 | 1886 | * Assert that the bounds are correct. |
eaeff70d | 1887 | */ |
b3deaf57 MD |
1888 | KKASSERT(hammer_btree_cmp(cursor->left_bound, |
1889 | &cursor->node->ondisk->elms[0].leaf.base) <= 0); | |
1890 | KKASSERT(hammer_btree_cmp(cursor->right_bound, | |
47197d71 | 1891 | &cursor->node->ondisk->elms[cursor->node->ondisk->count-1].leaf.base) > 0); |
36f82b23 MD |
1892 | KKASSERT(hammer_btree_cmp(cursor->left_bound, &cursor->key_beg) <= 0); |
1893 | KKASSERT(hammer_btree_cmp(cursor->right_bound, &cursor->key_beg) > 0); | |
76376933 | 1894 | |
6a37e7e4 MD |
1895 | done: |
1896 | hammer_cursor_downgrade(cursor); | |
1897 | return (error); | |
427e5fc6 MD |
1898 | } |
1899 | ||
adf01747 MD |
1900 | #if 0 |
1901 | ||
32c90105 MD |
1902 | /* |
1903 | * Recursively correct the right-hand boundary's create_tid to (tid) as | |
1904 | * long as the rest of the key matches. We have to recurse upward in | |
1905 | * the tree as well as down the left side of each parent's right node. | |
1906 | * | |
1907 | * Return EDEADLK if we were only partially successful, forcing the caller | |
1908 | * to try again. The original cursor is not modified. This routine can | |
1909 | * also fail with EDEADLK if it is forced to throw away a portion of its | |
1910 | * record history. | |
1911 | * | |
1912 | * The caller must pass a downgraded cursor to us (otherwise we can't dup it). | |
1913 | */ | |
1914 | struct hammer_rhb { | |
1915 | TAILQ_ENTRY(hammer_rhb) entry; | |
1916 | hammer_node_t node; | |
1917 | int index; | |
1918 | }; | |
1919 | ||
1920 | TAILQ_HEAD(hammer_rhb_list, hammer_rhb); | |
1921 | ||
1922 | int | |
1923 | hammer_btree_correct_rhb(hammer_cursor_t cursor, hammer_tid_t tid) | |
1924 | { | |
bac808fe | 1925 | struct hammer_mount *hmp; |
32c90105 MD |
1926 | struct hammer_rhb_list rhb_list; |
1927 | hammer_base_elm_t elm; | |
1928 | hammer_node_t orig_node; | |
1929 | struct hammer_rhb *rhb; | |
1930 | int orig_index; | |
1931 | int error; | |
1932 | ||
1933 | TAILQ_INIT(&rhb_list); | |
bac808fe | 1934 | hmp = cursor->trans->hmp; |
32c90105 MD |
1935 | |
1936 | /* | |
1937 | * Save our position so we can restore it on return. This also | |
1938 | * gives us a stable 'elm'. | |
1939 | */ | |
1940 | orig_node = cursor->node; | |
1941 | hammer_ref_node(orig_node); | |
1942 | hammer_lock_sh(&orig_node->lock); | |
1943 | orig_index = cursor->index; | |
1944 | elm = &orig_node->ondisk->elms[orig_index].base; | |
1945 | ||
1946 | /* | |
1947 | * Now build a list of parents going up, allocating a rhb | |
1948 | * structure for each one. | |
1949 | */ | |
1950 | while (cursor->parent) { | |
1951 | /* | |
1952 | * Stop if we no longer have any right-bounds to fix up | |
1953 | */ | |
1954 | if (elm->obj_id != cursor->right_bound->obj_id || | |
1955 | elm->rec_type != cursor->right_bound->rec_type || | |
1956 | elm->key != cursor->right_bound->key) { | |
1957 | break; | |
1958 | } | |
1959 | ||
1960 | /* | |
1961 | * Stop if the right-hand bound's create_tid does not | |
47197d71 | 1962 | * need to be corrected. |
32c90105 MD |
1963 | */ |
1964 | if (cursor->right_bound->create_tid >= tid) | |
1965 | break; | |
1966 | ||
bac808fe | 1967 | rhb = kmalloc(sizeof(*rhb), hmp->m_misc, M_WAITOK|M_ZERO); |
32c90105 MD |
1968 | rhb->node = cursor->parent; |
1969 | rhb->index = cursor->parent_index; | |
1970 | hammer_ref_node(rhb->node); | |
1971 | hammer_lock_sh(&rhb->node->lock); | |
1972 | TAILQ_INSERT_HEAD(&rhb_list, rhb, entry); | |
1973 | ||
1974 | hammer_cursor_up(cursor); | |
1975 | } | |
1976 | ||
1977 | /* | |
1978 | * now safely adjust the right hand bound for each rhb. This may | |
1979 | * also require taking the right side of the tree and iterating down | |
1980 | * ITS left side. | |
1981 | */ | |
1982 | error = 0; | |
1983 | while (error == 0 && (rhb = TAILQ_FIRST(&rhb_list)) != NULL) { | |
1984 | error = hammer_cursor_seek(cursor, rhb->node, rhb->index); | |
32c90105 MD |
1985 | if (error) |
1986 | break; | |
1987 | TAILQ_REMOVE(&rhb_list, rhb, entry); | |
1988 | hammer_unlock(&rhb->node->lock); | |
1989 | hammer_rel_node(rhb->node); | |
bac808fe | 1990 | kfree(rhb, hmp->m_misc); |
32c90105 MD |
1991 | |
1992 | switch (cursor->node->ondisk->type) { | |
1993 | case HAMMER_BTREE_TYPE_INTERNAL: | |
1994 | /* | |
1995 | * Right-boundary for parent at internal node | |
1996 | * is one element to the right of the element whos | |
1997 | * right boundary needs adjusting. We must then | |
1998 | * traverse down the left side correcting any left | |
1999 | * bounds (which may now be too far to the left). | |
2000 | */ | |
2001 | ++cursor->index; | |
2002 | error = hammer_btree_correct_lhb(cursor, tid); | |
2003 | break; | |
32c90105 MD |
2004 | default: |
2005 | panic("hammer_btree_correct_rhb(): Bad node type"); | |
2006 | error = EINVAL; | |
2007 | break; | |
2008 | } | |
2009 | } | |
2010 | ||
2011 | /* | |
2012 | * Cleanup | |
2013 | */ | |
2014 | while ((rhb = TAILQ_FIRST(&rhb_list)) != NULL) { | |
2015 | TAILQ_REMOVE(&rhb_list, rhb, entry); | |
2016 | hammer_unlock(&rhb->node->lock); | |
2017 | hammer_rel_node(rhb->node); | |
bac808fe | 2018 | kfree(rhb, hmp->m_misc); |
32c90105 MD |
2019 | } |
2020 | error = hammer_cursor_seek(cursor, orig_node, orig_index); | |
2021 | hammer_unlock(&orig_node->lock); | |
2022 | hammer_rel_node(orig_node); | |
2023 | return (error); | |
2024 | } | |
2025 | ||
2026 | /* | |
2027 | * Similar to rhb (in fact, rhb calls lhb), but corrects the left hand | |
2028 | * bound going downward starting at the current cursor position. | |
2029 | * | |
2030 | * This function does not restore the cursor after use. | |
2031 | */ | |
2032 | int | |
2033 | hammer_btree_correct_lhb(hammer_cursor_t cursor, hammer_tid_t tid) | |
2034 | { | |
2035 | struct hammer_rhb_list rhb_list; | |
2036 | hammer_base_elm_t elm; | |
2037 | hammer_base_elm_t cmp; | |
2038 | struct hammer_rhb *rhb; | |
bac808fe | 2039 | struct hammer_mount *hmp; |
32c90105 MD |
2040 | int error; |
2041 | ||
2042 | TAILQ_INIT(&rhb_list); | |
bac808fe | 2043 | hmp = cursor->trans->hmp; |
32c90105 MD |
2044 | |
2045 | cmp = &cursor->node->ondisk->elms[cursor->index].base; | |
2046 | ||
2047 | /* | |
2048 | * Record the node and traverse down the left-hand side for all | |
2049 | * matching records needing a boundary correction. | |
2050 | */ | |
2051 | error = 0; | |
2052 | for (;;) { | |
bac808fe | 2053 | rhb = kmalloc(sizeof(*rhb), hmp->m_misc, M_WAITOK|M_ZERO); |
32c90105 MD |
2054 | rhb->node = cursor->node; |
2055 | rhb->index = cursor->index; | |
2056 | hammer_ref_node(rhb->node); | |
2057 | hammer_lock_sh(&rhb->node->lock); | |
2058 | TAILQ_INSERT_HEAD(&rhb_list, rhb, entry); | |
2059 | ||
2060 | if (cursor->node->ondisk->type == HAMMER_BTREE_TYPE_INTERNAL) { | |
2061 | /* | |
2062 | * Nothing to traverse down if we are at the right | |
2063 | * boundary of an internal node. | |
2064 | */ | |
2065 | if (cursor->index == cursor->node->ondisk->count) | |
2066 | break; | |
2067 | } else { | |
2068 | elm = &cursor->node->ondisk->elms[cursor->index].base; | |
2069 | if (elm->btype == HAMMER_BTREE_TYPE_RECORD) | |
2070 | break; | |
47197d71 | 2071 | panic("Illegal leaf record type %02x", elm->btype); |
32c90105 MD |
2072 | } |
2073 | error = hammer_cursor_down(cursor); | |
2074 | if (error) | |
2075 | break; | |
2076 | ||
2077 | elm = &cursor->node->ondisk->elms[cursor->index].base; | |
2078 | if (elm->obj_id != cmp->obj_id || | |
2079 | elm->rec_type != cmp->rec_type || | |
2080 | elm->key != cmp->key) { | |
2081 | break; | |
2082 | } | |
2083 | if (elm->create_tid >= tid) | |
2084 | break; | |
2085 | ||
2086 | } | |
2087 | ||
2088 | /* | |
2089 | * Now we can safely adjust the left-hand boundary from the bottom-up. | |
2090 | * The last element we remove from the list is the caller's right hand | |
2091 | * boundary, which must also be adjusted. | |
2092 | */ | |
2093 | while (error == 0 && (rhb = TAILQ_FIRST(&rhb_list)) != NULL) { | |
2094 | error = hammer_cursor_seek(cursor, rhb->node, rhb->index); | |
2095 | if (error) | |
2096 | break; | |
2097 | TAILQ_REMOVE(&rhb_list, rhb, entry); | |
2098 | hammer_unlock(&rhb->node->lock); | |
2099 | hammer_rel_node(rhb->node); | |
bac808fe | 2100 | kfree(rhb, hmp->m_misc); |
32c90105 MD |
2101 | |
2102 | elm = &cursor->node->ondisk->elms[cursor->index].base; | |
2103 | if (cursor->node->ondisk->type == HAMMER_BTREE_TYPE_INTERNAL) { | |
36f82b23 | 2104 | hammer_modify_node(cursor->trans, cursor->node, |
19619882 MD |
2105 | &elm->create_tid, |
2106 | sizeof(elm->create_tid)); | |
32c90105 | 2107 | elm->create_tid = tid; |
10a5d1ba | 2108 | hammer_modify_node_done(cursor->node); |
32c90105 MD |
2109 | } else { |
2110 | panic("hammer_btree_correct_lhb(): Bad element type"); | |
2111 | } | |
2112 | } | |
2113 | ||
2114 | /* | |
2115 | * Cleanup | |
2116 | */ | |
2117 | while ((rhb = TAILQ_FIRST(&rhb_list)) != NULL) { | |
2118 | TAILQ_REMOVE(&rhb_list, rhb, entry); | |
2119 | hammer_unlock(&rhb->node->lock); | |
2120 | hammer_rel_node(rhb->node); | |
bac808fe | 2121 | kfree(rhb, hmp->m_misc); |
32c90105 MD |
2122 | } |
2123 | return (error); | |
2124 | } | |
2125 | ||
adf01747 MD |
2126 | #endif |
2127 | ||
427e5fc6 | 2128 | /* |
f36a9737 MD |
2129 | * Attempt to remove the locked, empty or want-to-be-empty B-Tree node at |
2130 | * (cursor->node). Returns 0 on success, EDEADLK if we could not complete | |
2131 | * the operation due to a deadlock, or some other error. | |
8cd0a023 | 2132 | * |
5c8d05e2 MD |
2133 | * This routine is initially called with an empty leaf and may be |
2134 | * recursively called with single-element internal nodes. | |
b3deaf57 | 2135 | * |
c82af904 MD |
2136 | * It should also be noted that when removing empty leaves we must be sure |
2137 | * to test and update mirror_tid because another thread may have deadlocked | |
5fa5c92f | 2138 | * against us (or someone) trying to propagate it up and cannot retry once |
c82af904 MD |
2139 | * the node has been deleted. |
2140 | * | |
f36a9737 MD |
2141 | * On return the cursor may end up pointing to an internal node, suitable |
2142 | * for further iteration but not for an immediate insertion or deletion. | |
8cd0a023 | 2143 | */ |
f36a9737 | 2144 | static int |
46fe7ae1 | 2145 | btree_remove(hammer_cursor_t cursor) |
8cd0a023 MD |
2146 | { |
2147 | hammer_node_ondisk_t ondisk; | |
195c19a1 | 2148 | hammer_btree_elm_t elm; |
195c19a1 | 2149 | hammer_node_t node; |
8cd0a023 | 2150 | hammer_node_t parent; |
fe7678ee | 2151 | const int esize = sizeof(*elm); |
8cd0a023 | 2152 | int error; |
8cd0a023 | 2153 | |
fe7678ee MD |
2154 | node = cursor->node; |
2155 | ||
47197d71 MD |
2156 | /* |
2157 | * When deleting the root of the filesystem convert it to | |
2158 | * an empty leaf node. Internal nodes cannot be empty. | |
2159 | */ | |
c82af904 MD |
2160 | ondisk = node->ondisk; |
2161 | if (ondisk->parent == 0) { | |
f36a9737 | 2162 | KKASSERT(cursor->parent == NULL); |
36f82b23 | 2163 | hammer_modify_node_all(cursor->trans, node); |
c82af904 | 2164 | KKASSERT(ondisk == node->ondisk); |
195c19a1 MD |
2165 | ondisk->type = HAMMER_BTREE_TYPE_LEAF; |
2166 | ondisk->count = 0; | |
10a5d1ba | 2167 | hammer_modify_node_done(node); |
b3deaf57 | 2168 | cursor->index = 0; |
47197d71 | 2169 | return(0); |
8cd0a023 MD |
2170 | } |
2171 | ||
c82af904 | 2172 | parent = cursor->parent; |
b3bad96f | 2173 | hammer_cursor_removed_node(node, parent, cursor->parent_index); |
c82af904 | 2174 | |
8cd0a023 | 2175 | /* |
f36a9737 MD |
2176 | * Attempt to remove the parent's reference to the child. If the |
2177 | * parent would become empty we have to recurse. If we fail we | |
2178 | * leave the parent pointing to an empty leaf node. | |
5c8d05e2 MD |
2179 | * |
2180 | * We have to recurse successfully before we can delete the internal | |
2181 | * node as it is illegal to have empty internal nodes. Even though | |
2182 | * the operation may be aborted we must still fixup any unlocked | |
2183 | * cursors as if we had deleted the element prior to recursing | |
2184 | * (by calling hammer_cursor_deleted_element()) so those cursors | |
2185 | * are properly forced up the chain by the recursion. | |
8cd0a023 | 2186 | */ |
f36a9737 MD |
2187 | if (parent->ondisk->count == 1) { |
2188 | /* | |
2189 | * This special cursor_up_locked() call leaves the original | |
2190 | * node exclusively locked and referenced, leaves the | |
2191 | * original parent locked (as the new node), and locks the | |
2192 | * new parent. It can return EDEADLK. | |
2193 | */ | |
2194 | error = hammer_cursor_up_locked(cursor); | |
2195 | if (error == 0) { | |
5c8d05e2 | 2196 | hammer_cursor_deleted_element(cursor->node, 0); |
f36a9737 MD |
2197 | error = btree_remove(cursor); |
2198 | if (error == 0) { | |
2199 | hammer_modify_node_all(cursor->trans, node); | |
2200 | ondisk = node->ondisk; | |
2201 | ondisk->type = HAMMER_BTREE_TYPE_DELETED; | |
2202 | ondisk->count = 0; | |
2203 | hammer_modify_node_done(node); | |
2204 | hammer_flush_node(node); | |
2205 | hammer_delete_node(cursor->trans, node); | |
2206 | } else { | |
3214ade6 MD |
2207 | /* |
2208 | * Defer parent removal because we could not | |
2209 | * get the lock, just let the leaf remain | |
2210 | * empty. | |
2211 | */ | |
2212 | /**/ | |
f36a9737 MD |
2213 | } |
2214 | hammer_unlock(&node->lock); | |
2215 | hammer_rel_node(node); | |
2216 | } else { | |
3214ade6 MD |
2217 | /* |
2218 | * Defer parent removal because we could not | |
2219 | * get the lock, just let the leaf remain | |
2220 | * empty. | |
2221 | */ | |
2222 | /**/ | |
f36a9737 MD |
2223 | } |
2224 | } else { | |
2225 | KKASSERT(parent->ondisk->count > 1); | |
6a37e7e4 | 2226 | |
f36a9737 MD |
2227 | hammer_modify_node_all(cursor->trans, parent); |
2228 | ondisk = parent->ondisk; | |
2229 | KKASSERT(ondisk->type == HAMMER_BTREE_TYPE_INTERNAL); | |
c82af904 | 2230 | |
f36a9737 MD |
2231 | elm = &ondisk->elms[cursor->parent_index]; |
2232 | KKASSERT(elm->internal.subtree_offset == node->node_offset); | |
2233 | KKASSERT(ondisk->count > 0); | |
4c038e17 MD |
2234 | |
2235 | /* | |
2236 | * We must retain the highest mirror_tid. The deleted | |
2237 | * range is now encompassed by the element to the left. | |
2238 | * If we are already at the left edge the new left edge | |
2239 | * inherits mirror_tid. | |
2240 | * | |
2241 | * Note that bounds of the parent to our parent may create | |
2242 | * a gap to the left of our left-most node or to the right | |
2243 | * of our right-most node. The gap is silently included | |
2244 | * in the mirror_tid's area of effect from the point of view | |
2245 | * of the scan. | |
2246 | */ | |
2247 | if (cursor->parent_index) { | |
2248 | if (elm[-1].internal.mirror_tid < | |
2249 | elm[0].internal.mirror_tid) { | |
2250 | elm[-1].internal.mirror_tid = | |
2251 | elm[0].internal.mirror_tid; | |
2252 | } | |
2253 | } else { | |
2254 | if (elm[1].internal.mirror_tid < | |
2255 | elm[0].internal.mirror_tid) { | |
2256 | elm[1].internal.mirror_tid = | |
2257 | elm[0].internal.mirror_tid; | |
2258 | } | |
2259 | } | |
2260 | ||
2261 | /* | |
2262 | * Delete the subtree reference in the parent | |
2263 | */ | |
f36a9737 MD |
2264 | bcopy(&elm[1], &elm[0], |
2265 | (ondisk->count - cursor->parent_index) * esize); | |
2266 | --ondisk->count; | |
10a5d1ba | 2267 | hammer_modify_node_done(parent); |
6c1f89f4 | 2268 | hammer_cursor_deleted_element(parent, cursor->parent_index); |
f36a9737 MD |
2269 | hammer_flush_node(node); |
2270 | hammer_delete_node(cursor->trans, node); | |
6a37e7e4 | 2271 | |
f36a9737 MD |
2272 | /* |
2273 | * cursor->node is invalid, cursor up to make the cursor | |
2274 | * valid again. | |
2275 | */ | |
2276 | error = hammer_cursor_up(cursor); | |
6a37e7e4 | 2277 | } |
f36a9737 | 2278 | return (error); |
6a37e7e4 MD |
2279 | } |
2280 | ||
602c6cb8 MD |
2281 | /* |
2282 | * Propagate cursor->trans->tid up the B-Tree starting at the current | |
2283 | * cursor position using pseudofs info gleaned from the passed inode. | |
2284 | * | |
2285 | * The passed inode has no relationship to the cursor position other | |
2286 | * then being in the same pseudofs as the insertion or deletion we | |
2287 | * are propagating the mirror_tid for. | |
2288 | */ | |
2289 | void | |
4c038e17 MD |
2290 | hammer_btree_do_propagation(hammer_cursor_t cursor, |
2291 | hammer_pseudofs_inmem_t pfsm, | |
602c6cb8 MD |
2292 | hammer_btree_leaf_elm_t leaf) |
2293 | { | |
adf01747 MD |
2294 | hammer_cursor_t ncursor; |
2295 | hammer_tid_t mirror_tid; | |
602c6cb8 MD |
2296 | int error; |
2297 | ||
2298 | /* | |
732a1697 MD |
2299 | * We do not propagate a mirror_tid if the filesystem was mounted |
2300 | * in no-mirror mode. | |
602c6cb8 | 2301 | */ |
732a1697 | 2302 | if (cursor->trans->hmp->master_id < 0) |
602c6cb8 | 2303 | return; |
602c6cb8 | 2304 | |
adf01747 MD |
2305 | /* |
2306 | * This is a bit of a hack because we cannot deadlock or return | |
2307 | * EDEADLK here. The related operation has already completed and | |
2308 | * we must propagate the mirror_tid now regardless. | |
2309 | * | |
2310 | * Generate a new cursor which inherits the original's locks and | |
2311 | * unlock the original. Use the new cursor to propagate the | |
2312 | * mirror_tid. Then clean up the new cursor and reacquire locks | |
2313 | * on the original. | |
2314 | * | |
2315 | * hammer_dup_cursor() cannot dup locks. The dup inherits the | |
2316 | * original's locks and the original is tracked and must be | |
2317 | * re-locked. | |
2318 | */ | |
2319 | mirror_tid = cursor->node->ondisk->mirror_tid; | |
a56cb012 | 2320 | KKASSERT(mirror_tid != 0); |
3f43fb33 | 2321 | ncursor = hammer_push_cursor(cursor); |
adf01747 MD |
2322 | error = hammer_btree_mirror_propagate(ncursor, mirror_tid); |
2323 | KKASSERT(error == 0); | |
3f43fb33 | 2324 | hammer_pop_cursor(cursor, ncursor); |
602c6cb8 MD |
2325 | } |
2326 | ||
2327 | ||
c82af904 MD |
2328 | /* |
2329 | * Propagate a mirror TID update upwards through the B-Tree to the root. | |
2330 | * | |
2331 | * A locked internal node must be passed in. The node will remain locked | |
2332 | * on return. | |
2333 | * | |
2334 | * This function syncs mirror_tid at the specified internal node's element, | |
2335 | * adjusts the node's aggregation mirror_tid, and then recurses upwards. | |
2336 | */ | |
602c6cb8 | 2337 | static int |
adf01747 | 2338 | hammer_btree_mirror_propagate(hammer_cursor_t cursor, hammer_tid_t mirror_tid) |
c82af904 MD |
2339 | { |
2340 | hammer_btree_internal_elm_t elm; | |
adf01747 | 2341 | hammer_node_t node; |
c82af904 MD |
2342 | int error; |
2343 | ||
adf01747 MD |
2344 | for (;;) { |
2345 | error = hammer_cursor_up(cursor); | |
2346 | if (error == 0) | |
2347 | error = hammer_cursor_upgrade(cursor); | |
2348 | while (error == EDEADLK) { | |
2349 | hammer_recover_cursor(cursor); | |
2350 | error = hammer_cursor_upgrade(cursor); | |
2351 | } | |
2352 | if (error) | |
2353 | break; | |
2354 | node = cursor->node; | |
2355 | KKASSERT (node->ondisk->type == HAMMER_BTREE_TYPE_INTERNAL); | |
c82af904 | 2356 | |
adf01747 MD |
2357 | /* |
2358 | * Adjust the node's element | |
2359 | */ | |
2360 | elm = &node->ondisk->elms[cursor->index].internal; | |
2361 | if (elm->mirror_tid >= mirror_tid) | |
2362 | break; | |
2363 | hammer_modify_node(cursor->trans, node, &elm->mirror_tid, | |
2364 | sizeof(elm->mirror_tid)); | |
2365 | elm->mirror_tid = mirror_tid; | |
2366 | hammer_modify_node_done(node); | |
02325004 MD |
2367 | if (hammer_debug_general & 0x0002) { |
2368 | kprintf("mirror_propagate: propagate " | |
2369 | "%016llx @%016llx:%d\n", | |
973c11b9 MD |
2370 | (long long)mirror_tid, |
2371 | (long long)node->node_offset, | |
2372 | cursor->index); | |
02325004 MD |
2373 | } |
2374 | ||
c82af904 | 2375 | |
adf01747 MD |
2376 | /* |
2377 | * Adjust the node's mirror_tid aggregator | |
2378 | */ | |
2379 | if (node->ondisk->mirror_tid >= mirror_tid) | |
2380 | return(0); | |
2381 | hammer_modify_node_field(cursor->trans, node, mirror_tid); | |
2382 | node->ondisk->mirror_tid = mirror_tid; | |
2383 | hammer_modify_node_done(node); | |
02325004 MD |
2384 | if (hammer_debug_general & 0x0002) { |
2385 | kprintf("mirror_propagate: propagate " | |
2386 | "%016llx @%016llx\n", | |
973c11b9 MD |
2387 | (long long)mirror_tid, |
2388 | (long long)node->node_offset); | |
02325004 | 2389 | } |
c82af904 | 2390 | } |
adf01747 MD |
2391 | if (error == ENOENT) |
2392 | error = 0; | |
c82af904 MD |
2393 | return(error); |
2394 | } | |
2395 | ||
2396 | hammer_node_t | |
82010f9f MD |
2397 | hammer_btree_get_parent(hammer_transaction_t trans, hammer_node_t node, |
2398 | int *parent_indexp, int *errorp, int try_exclusive) | |
c82af904 MD |
2399 | { |
2400 | hammer_node_t parent; | |
2401 | hammer_btree_elm_t elm; | |
2402 | int i; | |
2403 | ||
2404 | /* | |
2405 | * Get the node | |
2406 | */ | |
82010f9f | 2407 | parent = hammer_get_node(trans, node->ondisk->parent, 0, errorp); |
c82af904 MD |
2408 | if (*errorp) { |
2409 | KKASSERT(parent == NULL); | |
2410 | return(NULL); | |
2411 | } | |
2412 | KKASSERT ((parent->flags & HAMMER_NODE_DELETED) == 0); | |
2413 | ||
2414 | /* | |
2415 | * Lock the node | |
2416 | */ | |
2417 | if (try_exclusive) { | |
2418 | if (hammer_lock_ex_try(&parent->lock)) { | |
2419 | hammer_rel_node(parent); | |
2420 | *errorp = EDEADLK; | |
2421 | return(NULL); | |
2422 | } | |
2423 | } else { | |
2424 | hammer_lock_sh(&parent->lock); | |
2425 | } | |
2426 | ||
2427 | /* | |
2428 | * Figure out which element in the parent is pointing to the | |
2429 | * child. | |
2430 | */ | |
2431 | if (node->ondisk->count) { | |
2432 | i = hammer_btree_search_node(&node->ondisk->elms[0].base, | |
2433 | parent->ondisk); | |
2434 | } else { | |
2435 | i = 0; | |
2436 | } | |
2437 | while (i < parent->ondisk->count) { | |
2438 | elm = &parent->ondisk->elms[i]; | |
2439 | if (elm->internal.subtree_offset == node->node_offset) | |
2440 | break; | |
2441 | ++i; | |
2442 | } | |
2443 | if (i == parent->ondisk->count) { | |
2444 | hammer_unlock(&parent->lock); | |
2445 | panic("Bad B-Tree link: parent %p node %p\n", parent, node); | |
2446 | } | |
2447 | *parent_indexp = i; | |
2448 | KKASSERT(*errorp == 0); | |
2449 | return(parent); | |
2450 | } | |
2451 | ||
7f7c1f84 | 2452 | /* |
fe7678ee MD |
2453 | * The element (elm) has been moved to a new internal node (node). |
2454 | * | |
2455 | * If the element represents a pointer to an internal node that node's | |
2456 | * parent must be adjusted to the element's new location. | |
2457 | * | |
6a37e7e4 | 2458 | * XXX deadlock potential here with our exclusive locks |
7f7c1f84 | 2459 | */ |
7f7c1f84 | 2460 | int |
36f82b23 MD |
2461 | btree_set_parent(hammer_transaction_t trans, hammer_node_t node, |
2462 | hammer_btree_elm_t elm) | |
7f7c1f84 | 2463 | { |
7f7c1f84 MD |
2464 | hammer_node_t child; |
2465 | int error; | |
2466 | ||
2467 | error = 0; | |
2468 | ||
fe7678ee | 2469 | switch(elm->base.btype) { |
7f7c1f84 | 2470 | case HAMMER_BTREE_TYPE_INTERNAL: |
fe7678ee | 2471 | case HAMMER_BTREE_TYPE_LEAF: |
82010f9f | 2472 | child = hammer_get_node(trans, elm->internal.subtree_offset, |
19619882 | 2473 | 0, &error); |
7f7c1f84 | 2474 | if (error == 0) { |
c9b9e29d | 2475 | hammer_modify_node_field(trans, child, parent); |
7f7c1f84 | 2476 | child->ondisk->parent = node->node_offset; |
10a5d1ba | 2477 | hammer_modify_node_done(child); |
7f7c1f84 MD |
2478 | hammer_rel_node(child); |
2479 | } | |
2480 | break; | |
7f7c1f84 | 2481 | default: |
fe7678ee | 2482 | break; |
7f7c1f84 MD |
2483 | } |
2484 | return(error); | |
2485 | } | |
2486 | ||
1775b6a0 MD |
2487 | /* |
2488 | * Initialize the root of a recursive B-Tree node lock list structure. | |
2489 | */ | |
2490 | void | |
2491 | hammer_node_lock_init(hammer_node_lock_t parent, hammer_node_t node) | |
2492 | { | |
2493 | TAILQ_INIT(&parent->list); | |
2494 | parent->parent = NULL; | |
2495 | parent->node = node; | |
2496 | parent->index = -1; | |
2497 | parent->count = node->ondisk->count; | |
2498 | parent->copy = NULL; | |
2499 | parent->flags = 0; | |
2500 | } | |
2501 | ||
b33e2cc0 MD |
2502 | /* |
2503 | * Exclusively lock all the children of node. This is used by the split | |
2504 | * code to prevent anyone from accessing the children of a cursor node | |
2505 | * while we fix-up its parent offset. | |
2506 | * | |
2507 | * If we don't lock the children we can really mess up cursors which block | |
2508 | * trying to cursor-up into our node. | |
2509 | * | |
b33e2cc0 MD |
2510 | * On failure EDEADLK (or some other error) is returned. If a deadlock |
2511 | * error is returned the cursor is adjusted to block on termination. | |
1775b6a0 MD |
2512 | * |
2513 | * The caller is responsible for managing parent->node, the root's node | |
2514 | * is usually aliased from a cursor. | |
b33e2cc0 MD |
2515 | */ |
2516 | int | |
1775b6a0 MD |
2517 | hammer_btree_lock_children(hammer_cursor_t cursor, int depth, |
2518 | hammer_node_lock_t parent) | |
b33e2cc0 MD |
2519 | { |
2520 | hammer_node_t node; | |
1775b6a0 | 2521 | hammer_node_lock_t item; |
b33e2cc0 MD |
2522 | hammer_node_ondisk_t ondisk; |
2523 | hammer_btree_elm_t elm; | |
b33e2cc0 | 2524 | hammer_node_t child; |
bac808fe | 2525 | struct hammer_mount *hmp; |
b33e2cc0 MD |
2526 | int error; |
2527 | int i; | |
2528 | ||
1775b6a0 | 2529 | node = parent->node; |
b33e2cc0 MD |
2530 | ondisk = node->ondisk; |
2531 | error = 0; | |
bac808fe | 2532 | hmp = cursor->trans->hmp; |
7bc5b8c2 MD |
2533 | |
2534 | /* | |
2535 | * We really do not want to block on I/O with exclusive locks held, | |
1775b6a0 MD |
2536 | * pre-get the children before trying to lock the mess. This is |
2537 | * only done one-level deep for now. | |
7bc5b8c2 MD |
2538 | */ |
2539 | for (i = 0; i < ondisk->count; ++i) { | |
cb51be26 | 2540 | ++hammer_stats_btree_elements; |
7bc5b8c2 MD |
2541 | elm = &ondisk->elms[i]; |
2542 | if (elm->base.btype != HAMMER_BTREE_TYPE_LEAF && | |
2543 | elm->base.btype != HAMMER_BTREE_TYPE_INTERNAL) { | |
2544 | continue; | |
2545 | } | |
82010f9f | 2546 | child = hammer_get_node(cursor->trans, |
7bc5b8c2 MD |
2547 | elm->internal.subtree_offset, |
2548 | 0, &error); | |
2549 | if (child) | |
2550 | hammer_rel_node(child); | |
2551 | } | |
2552 | ||
2553 | /* | |
2554 | * Do it for real | |
2555 | */ | |
b33e2cc0 | 2556 | for (i = 0; error == 0 && i < ondisk->count; ++i) { |
cb51be26 | 2557 | ++hammer_stats_btree_elements; |
b33e2cc0 MD |
2558 | elm = &ondisk->elms[i]; |
2559 | ||
b33e2cc0 MD |
2560 | switch(elm->base.btype) { |
2561 | case HAMMER_BTREE_TYPE_INTERNAL: | |
2562 | case HAMMER_BTREE_TYPE_LEAF: | |
f36a9737 | 2563 | KKASSERT(elm->internal.subtree_offset != 0); |
82010f9f | 2564 | child = hammer_get_node(cursor->trans, |
b33e2cc0 | 2565 | elm->internal.subtree_offset, |
19619882 | 2566 | 0, &error); |
b33e2cc0 | 2567 | break; |
b33e2cc0 | 2568 | default: |
47197d71 | 2569 | child = NULL; |
b33e2cc0 MD |
2570 | break; |
2571 | } | |
2572 | if (child) { | |
2573 | if (hammer_lock_ex_try(&child->lock) != 0) { | |
2574 | if (cursor->deadlk_node == NULL) { | |
1ff9f58e | 2575 | cursor->deadlk_node = child; |
b33e2cc0 MD |
2576 | hammer_ref_node(cursor->deadlk_node); |
2577 | } | |
2578 | error = EDEADLK; | |
a84a197d | 2579 | hammer_rel_node(child); |
b33e2cc0 | 2580 | } else { |
1775b6a0 MD |
2581 | item = kmalloc(sizeof(*item), hmp->m_misc, |
2582 | M_WAITOK|M_ZERO); | |
2583 | TAILQ_INSERT_TAIL(&parent->list, item, entry); | |
2584 | TAILQ_INIT(&item->list); | |
2585 | item->parent = parent; | |
b33e2cc0 | 2586 | item->node = child; |
1775b6a0 MD |
2587 | item->index = i; |
2588 | item->count = child->ondisk->count; | |
2589 | ||
2590 | /* | |
2591 | * Recurse (used by the rebalancing code) | |
2592 | */ | |
2593 | if (depth > 1 && elm->base.btype == HAMMER_BTREE_TYPE_INTERNAL) { | |
2594 | error = hammer_btree_lock_children( | |
2595 | cursor, | |
2596 | depth - 1, | |
2597 | item); | |
2598 | } | |
b33e2cc0 MD |
2599 | } |
2600 | } | |
2601 | } | |
2602 | if (error) | |
1775b6a0 | 2603 | hammer_btree_unlock_children(cursor, parent); |
b33e2cc0 MD |
2604 | return(error); |
2605 | } | |
2606 | ||
1775b6a0 MD |
2607 | /* |
2608 | * Create an in-memory copy of all B-Tree nodes listed, recursively, | |
2609 | * including the parent. | |
2610 | */ | |
2611 | void | |
2612 | hammer_btree_lock_copy(hammer_cursor_t cursor, hammer_node_lock_t parent) | |
2613 | { | |
2614 | hammer_mount_t hmp = cursor->trans->hmp; | |
2615 | hammer_node_lock_t item; | |
2616 | ||
2617 | if (parent->copy == NULL) { | |
2618 | parent->copy = kmalloc(sizeof(*parent->copy), hmp->m_misc, | |
2619 | M_WAITOK); | |
2620 | *parent->copy = *parent->node->ondisk; | |
2621 | } | |
2622 | TAILQ_FOREACH(item, &parent->list, entry) { | |
2623 | hammer_btree_lock_copy(cursor, item); | |
2624 | } | |
2625 | } | |
b33e2cc0 MD |
2626 | |
2627 | /* | |
1775b6a0 | 2628 | * Recursively sync modified copies to the media. |
b33e2cc0 | 2629 | */ |
7ddc70d1 | 2630 | int |
1775b6a0 | 2631 | hammer_btree_sync_copy(hammer_cursor_t cursor, hammer_node_lock_t parent) |
b33e2cc0 | 2632 | { |
1775b6a0 | 2633 | hammer_node_lock_t item; |
7ddc70d1 | 2634 | int count = 0; |
1775b6a0 MD |
2635 | |
2636 | if (parent->flags & HAMMER_NODE_LOCK_UPDATED) { | |
7ddc70d1 | 2637 | ++count; |
1775b6a0 MD |
2638 | hammer_modify_node_all(cursor->trans, parent->node); |
2639 | *parent->node->ondisk = *parent->copy; | |
2640 | hammer_modify_node_done(parent->node); | |
2641 | if (parent->copy->type == HAMMER_BTREE_TYPE_DELETED) { | |
2642 | hammer_flush_node(parent->node); | |
2643 | hammer_delete_node(cursor->trans, parent->node); | |
2644 | } | |
2645 | } | |
2646 | TAILQ_FOREACH(item, &parent->list, entry) { | |
7ddc70d1 | 2647 | count += hammer_btree_sync_copy(cursor, item); |
1775b6a0 | 2648 | } |
7ddc70d1 | 2649 | return(count); |
1775b6a0 | 2650 | } |
b33e2cc0 | 2651 | |
1775b6a0 MD |
2652 | /* |
2653 | * Release previously obtained node locks. The caller is responsible for | |
2654 | * cleaning up parent->node itself (its usually just aliased from a cursor), | |
2655 | * but this function will take care of the copies. | |
2656 | */ | |
2657 | void | |
2658 | hammer_btree_unlock_children(hammer_cursor_t cursor, hammer_node_lock_t parent) | |
2659 | { | |
2660 | hammer_node_lock_t item; | |
2661 | ||
2662 | if (parent->copy) { | |
2663 | kfree(parent->copy, cursor->trans->hmp->m_misc); | |
2664 | parent->copy = NULL; /* safety */ | |
2665 | } | |
2666 | while ((item = TAILQ_FIRST(&parent->list)) != NULL) { | |
2667 | TAILQ_REMOVE(&parent->list, item, entry); | |
2668 | hammer_btree_unlock_children(cursor, item); | |
b33e2cc0 MD |
2669 | hammer_unlock(&item->node->lock); |
2670 | hammer_rel_node(item->node); | |
bac808fe | 2671 | kfree(item, cursor->trans->hmp->m_misc); |
b33e2cc0 MD |
2672 | } |
2673 | } | |
2674 | ||
8cd0a023 MD |
2675 | /************************************************************************ |
2676 | * MISCELLANIOUS SUPPORT * | |
2677 | ************************************************************************/ | |
2678 | ||
2679 | /* | |
d26d0ae9 | 2680 | * Compare two B-Tree elements, return -N, 0, or +N (e.g. similar to strcmp). |
8cd0a023 | 2681 | * |
d113fda1 | 2682 | * Note that for this particular function a return value of -1, 0, or +1 |
9582c7da | 2683 | * can denote a match if create_tid is otherwise discounted. A create_tid |
d5530d22 | 2684 | * of zero is considered to be 'infinity' in comparisons. |
d113fda1 | 2685 | * |
8cd0a023 | 2686 | * See also hammer_rec_rb_compare() and hammer_rec_cmp() in hammer_object.c. |
8cd0a023 MD |
2687 | */ |
2688 | int | |
2689 | hammer_btree_cmp(hammer_base_elm_t key1, hammer_base_elm_t key2) | |
2690 | { | |
2f85fa4d MD |
2691 | if (key1->localization < key2->localization) |
2692 | return(-5); | |
2693 | if (key1->localization > key2->localization) | |
2694 | return(5); | |
2695 | ||
d26d0ae9 MD |
2696 | if (key1->obj_id < key2->obj_id) |
2697 | return(-4); | |
2698 | if (key1->obj_id > key2->obj_id) | |
2699 | return(4); | |
8cd0a023 | 2700 | |
d26d0ae9 MD |
2701 | if (key1->rec_type < key2->rec_type) |
2702 | return(-3); | |
2703 | if (key1->rec_type > key2->rec_type) | |
2704 | return(3); | |
8cd0a023 | 2705 | |
8cd0a023 MD |
2706 | if (key1->key < key2->key) |
2707 | return(-2); | |
2708 | if (key1->key > key2->key) | |
2709 | return(2); | |
d113fda1 | 2710 | |
d5530d22 | 2711 | /* |
9582c7da MD |
2712 | * A create_tid of zero indicates a record which is undeletable |
2713 | * and must be considered to have a value of positive infinity. | |
d5530d22 | 2714 | */ |
9582c7da MD |
2715 | if (key1->create_tid == 0) { |
2716 | if (key2->create_tid == 0) | |
d5530d22 MD |
2717 | return(0); |
2718 | return(1); | |
2719 | } | |
9582c7da | 2720 | if (key2->create_tid == 0) |
d5530d22 | 2721 | return(-1); |
9582c7da | 2722 | if (key1->create_tid < key2->create_tid) |
d113fda1 | 2723 | return(-1); |
9582c7da | 2724 | if (key1->create_tid > key2->create_tid) |
d113fda1 | 2725 | return(1); |
8cd0a023 MD |
2726 | return(0); |
2727 | } | |
2728 | ||
c0ade690 | 2729 | /* |
d5530d22 MD |
2730 | * Test a timestamp against an element to determine whether the |
2731 | * element is visible. A timestamp of 0 means 'infinity'. | |
c0ade690 MD |
2732 | */ |
2733 | int | |
d5530d22 | 2734 | hammer_btree_chkts(hammer_tid_t asof, hammer_base_elm_t base) |
c0ade690 | 2735 | { |
d5530d22 MD |
2736 | if (asof == 0) { |
2737 | if (base->delete_tid) | |
2738 | return(1); | |
2739 | return(0); | |
2740 | } | |
2741 | if (asof < base->create_tid) | |
d26d0ae9 | 2742 | return(-1); |
d5530d22 | 2743 | if (base->delete_tid && asof >= base->delete_tid) |
d26d0ae9 | 2744 | return(1); |
c0ade690 MD |
2745 | return(0); |
2746 | } | |
2747 | ||
8cd0a023 MD |
2748 | /* |
2749 | * Create a separator half way inbetween key1 and key2. For fields just | |
d5530d22 MD |
2750 | * one unit apart, the separator will match key2. key1 is on the left-hand |
2751 | * side and key2 is on the right-hand side. | |
8cd0a023 | 2752 | * |
9391cded | 2753 | * key2 must be >= the separator. It is ok for the separator to match key2. |
36f82b23 | 2754 | * |
9391cded MD |
2755 | * NOTE: Even if key1 does not match key2, the separator may wind up matching |
2756 | * key2. | |
2757 | * | |
2758 | * NOTE: It might be beneficial to just scrap this whole mess and just | |
2759 | * set the separator to key2. | |
8cd0a023 MD |
2760 | */ |
2761 | #define MAKE_SEPARATOR(key1, key2, dest, field) \ | |
2762 | dest->field = key1->field + ((key2->field - key1->field + 1) >> 1); | |
2763 | ||
2764 | static void | |
2765 | hammer_make_separator(hammer_base_elm_t key1, hammer_base_elm_t key2, | |
2766 | hammer_base_elm_t dest) | |
2767 | { | |
2768 | bzero(dest, sizeof(*dest)); | |
d5530d22 | 2769 | |
9391cded MD |
2770 | dest->rec_type = key2->rec_type; |
2771 | dest->key = key2->key; | |
2f85fa4d | 2772 | dest->obj_id = key2->obj_id; |
9391cded MD |
2773 | dest->create_tid = key2->create_tid; |
2774 | ||
2f85fa4d MD |
2775 | MAKE_SEPARATOR(key1, key2, dest, localization); |
2776 | if (key1->localization == key2->localization) { | |
2777 | MAKE_SEPARATOR(key1, key2, dest, obj_id); | |
2778 | if (key1->obj_id == key2->obj_id) { | |
2779 | MAKE_SEPARATOR(key1, key2, dest, rec_type); | |
2780 | if (key1->rec_type == key2->rec_type) { | |
2781 | MAKE_SEPARATOR(key1, key2, dest, key); | |
2782 | /* | |
2783 | * Don't bother creating a separator for | |
2784 | * create_tid, which also conveniently avoids | |
2785 | * having to handle the create_tid == 0 | |
2786 | * (infinity) case. Just leave create_tid | |
2787 | * set to key2. | |
2788 | * | |
2789 | * Worst case, dest matches key2 exactly, | |
2790 | * which is acceptable. | |
2791 | */ | |
2792 | } | |
d5530d22 | 2793 | } |
d113fda1 | 2794 | } |
8cd0a023 MD |
2795 | } |
2796 | ||
2797 | #undef MAKE_SEPARATOR | |
2798 | ||
2799 | /* | |
2800 | * Return whether a generic internal or leaf node is full | |
2801 | */ | |
2802 | static int | |
2803 | btree_node_is_full(hammer_node_ondisk_t node) | |
2804 | { | |
2805 | switch(node->type) { | |
2806 | case HAMMER_BTREE_TYPE_INTERNAL: | |
2807 | if (node->count == HAMMER_BTREE_INT_ELMS) | |
2808 | return(1); | |
2809 | break; | |
2810 | case HAMMER_BTREE_TYPE_LEAF: | |
2811 | if (node->count == HAMMER_BTREE_LEAF_ELMS) | |
2812 | return(1); | |
2813 | break; | |
2814 | default: | |
2815 | panic("illegal btree subtype"); | |
2816 | } | |
2817 | return(0); | |
2818 | } | |
9944ae54 | 2819 | |
8cd0a023 MD |
2820 | #if 0 |
2821 | static int | |
2822 | btree_max_elements(u_int8_t type) | |
2823 | { | |
2824 | if (type == HAMMER_BTREE_TYPE_LEAF) | |
2825 | return(HAMMER_BTREE_LEAF_ELMS); | |
2826 | if (type == HAMMER_BTREE_TYPE_INTERNAL) | |
2827 | return(HAMMER_BTREE_INT_ELMS); | |
2828 | panic("btree_max_elements: bad type %d\n", type); | |
2829 | } | |
2830 | #endif | |
2831 | ||
c0ade690 MD |
2832 | void |
2833 | hammer_print_btree_node(hammer_node_ondisk_t ondisk) | |
2834 | { | |
2835 | hammer_btree_elm_t elm; | |
2836 | int i; | |
2837 | ||
47197d71 | 2838 | kprintf("node %p count=%d parent=%016llx type=%c\n", |
973c11b9 MD |
2839 | ondisk, ondisk->count, |
2840 | (long long)ondisk->parent, ondisk->type); | |
c0ade690 MD |
2841 | |
2842 | /* | |
2843 | * Dump both boundary elements if an internal node | |
2844 | */ | |
2845 | if (ondisk->type == HAMMER_BTREE_TYPE_INTERNAL) { | |
2846 | for (i = 0; i <= ondisk->count; ++i) { | |
2847 | elm = &ondisk->elms[i]; | |
2848 | hammer_print_btree_elm(elm, ondisk->type, i); | |
2849 | } | |
2850 | } else { | |
2851 | for (i = 0; i < ondisk->count; ++i) { | |
2852 | elm = &ondisk->elms[i]; | |
2853 | hammer_print_btree_elm(elm, ondisk->type, i); | |
2854 | } | |
2855 | } | |
2856 | } | |
2857 | ||
2858 | void | |
2859 | hammer_print_btree_elm(hammer_btree_elm_t elm, u_int8_t type, int i) | |
2860 | { | |
2861 | kprintf(" %2d", i); | |
973c11b9 MD |
2862 | kprintf("\tobj_id = %016llx\n", (long long)elm->base.obj_id); |
2863 | kprintf("\tkey = %016llx\n", (long long)elm->base.key); | |
2864 | kprintf("\tcreate_tid = %016llx\n", (long long)elm->base.create_tid); | |
2865 | kprintf("\tdelete_tid = %016llx\n", (long long)elm->base.delete_tid); | |
c0ade690 MD |
2866 | kprintf("\trec_type = %04x\n", elm->base.rec_type); |
2867 | kprintf("\tobj_type = %02x\n", elm->base.obj_type); | |
fe7678ee MD |
2868 | kprintf("\tbtype = %02x (%c)\n", |
2869 | elm->base.btype, | |
2870 | (elm->base.btype ? elm->base.btype : '?')); | |
2f85fa4d | 2871 | kprintf("\tlocalization = %02x\n", elm->base.localization); |
fe7678ee MD |
2872 | |
2873 | switch(type) { | |
2874 | case HAMMER_BTREE_TYPE_INTERNAL: | |
47197d71 | 2875 | kprintf("\tsubtree_off = %016llx\n", |
973c11b9 | 2876 | (long long)elm->internal.subtree_offset); |
fe7678ee | 2877 | break; |
fe7678ee | 2878 | case HAMMER_BTREE_TYPE_RECORD: |
973c11b9 MD |
2879 | kprintf("\tdata_offset = %016llx\n", |
2880 | (long long)elm->leaf.data_offset); | |
c0ade690 MD |
2881 | kprintf("\tdata_len = %08x\n", elm->leaf.data_len); |
2882 | kprintf("\tdata_crc = %08x\n", elm->leaf.data_crc); | |
fe7678ee | 2883 | break; |
c0ade690 MD |
2884 | } |
2885 | } |