Switch from bioq_insert_tail() to bioqdisksort(). When the kernel is
[dragonfly.git] / sys / vfs / hammer / hammer_btree.c
CommitLineData
427e5fc6 1/*
b84de5af 2 * Copyright (c) 2007-2008 The DragonFly Project. All rights reserved.
427e5fc6
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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 *
47637bff 34 * $DragonFly: src/sys/vfs/hammer/hammer_btree.c,v 1.50 2008/06/07 07:41:51 dillon Exp $
427e5fc6
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35 */
36
37/*
8cd0a023 38 * HAMMER B-Tree index
427e5fc6
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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
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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
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46 * instead of sub-tree pointers.
47 *
8cd0a023 48 * A B-Tree internal node looks like this:
427e5fc6
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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
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54 *
55 * L L L L L L L L <-- leaf elemenets
56 *
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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 *
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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 *
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68 * B-Trees also make the stacking of trees fairly straightforward.
69 *
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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
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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
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80 */
81#include "hammer.h"
82#include <sys/buf.h>
83#include <sys/buf2.h>
66325755 84
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85static int btree_search(hammer_cursor_t cursor, int flags);
86static int btree_split_internal(hammer_cursor_t cursor);
87static int btree_split_leaf(hammer_cursor_t cursor);
46fe7ae1 88static int btree_remove(hammer_cursor_t cursor);
fe7678ee 89static int btree_node_is_full(hammer_node_ondisk_t node);
8cd0a023
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90static void hammer_make_separator(hammer_base_elm_t key1,
91 hammer_base_elm_t key2, hammer_base_elm_t dest);
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92
93/*
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94 * Iterate records after a search. The cursor is iterated forwards past
95 * the current record until a record matching the key-range requirements
96 * is found. ENOENT is returned if the iteration goes past the ending
6a37e7e4 97 * key.
66325755 98 *
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99 * The iteration is inclusive of key_beg and can be inclusive or exclusive
100 * of key_end depending on whether HAMMER_CURSOR_END_INCLUSIVE is set.
66325755 101 *
eaeff70d 102 * When doing an as-of search (cursor->asof != 0), key_beg.create_tid
9582c7da 103 * may be modified by B-Tree functions.
d5530d22 104 *
8cd0a023 105 * cursor->key_beg may or may not be modified by this function during
d26d0ae9
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106 * the iteration. XXX future - in case of an inverted lock we may have
107 * to reinitiate the lookup and set key_beg to properly pick up where we
108 * left off.
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109 *
110 * NOTE! EDEADLK *CANNOT* be returned by this procedure.
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111 */
112int
8cd0a023 113hammer_btree_iterate(hammer_cursor_t cursor)
66325755 114{
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115 hammer_node_ondisk_t node;
116 hammer_btree_elm_t elm;
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117 int error;
118 int r;
119 int s;
120
121 /*
8cd0a023 122 * Skip past the current record
66325755 123 */
8cd0a023 124 node = cursor->node->ondisk;
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125 if (node == NULL)
126 return(ENOENT);
c0ade690
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127 if (cursor->index < node->count &&
128 (cursor->flags & HAMMER_CURSOR_ATEDISK)) {
66325755 129 ++cursor->index;
c0ade690 130 }
66325755 131
8cd0a023
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132 /*
133 * Loop until an element is found or we are done.
134 */
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135 for (;;) {
136 /*
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137 * We iterate up the tree and then index over one element
138 * while we are at the last element in the current node.
139 *
47197d71 140 * If we are at the root of the filesystem, cursor_up
8cd0a023
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141 * returns ENOENT.
142 *
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143 * XXX this could be optimized by storing the information in
144 * the parent reference.
195c19a1
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145 *
146 * XXX we can lose the node lock temporarily, this could mess
147 * up our scan.
66325755 148 */
47637bff 149 ++hammer_stats_btree_iterations;
8cd0a023 150 if (cursor->index == node->count) {
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151 if (hammer_debug_btree) {
152 kprintf("BRACKETU %016llx[%d] -> %016llx[%d] (td=%p)\n",
153 cursor->node->node_offset,
154 cursor->index,
155 (cursor->parent ? cursor->parent->node_offset : -1),
156 cursor->parent_index,
157 curthread);
158 }
159 KKASSERT(cursor->parent == NULL || cursor->parent->ondisk->elms[cursor->parent_index].internal.subtree_offset == cursor->node->node_offset);
6a37e7e4 160 error = hammer_cursor_up(cursor);
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161 if (error)
162 break;
46fe7ae1 163 /* reload stale pointer */
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164 node = cursor->node->ondisk;
165 KKASSERT(cursor->index != node->count);
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166
167 /*
168 * If we are reblocking we want to return internal
169 * nodes.
170 */
171 if (cursor->flags & HAMMER_CURSOR_REBLOCKING) {
172 cursor->flags |= HAMMER_CURSOR_ATEDISK;
173 return(0);
174 }
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175 ++cursor->index;
176 continue;
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177 }
178
179 /*
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180 * Check internal or leaf element. Determine if the record
181 * at the cursor has gone beyond the end of our range.
66325755 182 *
47197d71 183 * We recurse down through internal nodes.
66325755 184 */
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185 if (node->type == HAMMER_BTREE_TYPE_INTERNAL) {
186 elm = &node->elms[cursor->index];
d26d0ae9
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187 r = hammer_btree_cmp(&cursor->key_end, &elm[0].base);
188 s = hammer_btree_cmp(&cursor->key_beg, &elm[1].base);
b3deaf57 189 if (hammer_debug_btree) {
2f85fa4d 190 kprintf("BRACKETL %016llx[%d] %016llx %02x %016llx lo=%02x %d (td=%p)\n",
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191 cursor->node->node_offset,
192 cursor->index,
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193 elm[0].internal.base.obj_id,
194 elm[0].internal.base.rec_type,
195 elm[0].internal.base.key,
2f85fa4d 196 elm[0].internal.base.localization,
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197 r,
198 curthread
b3deaf57 199 );
2f85fa4d 200 kprintf("BRACKETR %016llx[%d] %016llx %02x %016llx lo=%02x %d\n",
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201 cursor->node->node_offset,
202 cursor->index + 1,
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203 elm[1].internal.base.obj_id,
204 elm[1].internal.base.rec_type,
205 elm[1].internal.base.key,
2f85fa4d 206 elm[1].internal.base.localization,
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207 s
208 );
209 }
210
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211 if (r < 0) {
212 error = ENOENT;
213 break;
66325755 214 }
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215 if (r == 0 && (cursor->flags &
216 HAMMER_CURSOR_END_INCLUSIVE) == 0) {
d26d0ae9 217 error = ENOENT;
8cd0a023 218 break;
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219 }
220 KKASSERT(s <= 0);
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221
222 /*
f36a9737 223 * Better not be zero
6a37e7e4 224 */
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225 KKASSERT(elm->internal.subtree_offset != 0);
226
227 error = hammer_cursor_down(cursor);
228 if (error)
229 break;
230 KKASSERT(cursor->index == 0);
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231 /* reload stale pointer */
232 node = cursor->node->ondisk;
fe7678ee 233 continue;
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234 } else {
235 elm = &node->elms[cursor->index];
236 r = hammer_btree_cmp(&cursor->key_end, &elm->base);
b3deaf57 237 if (hammer_debug_btree) {
2f85fa4d 238 kprintf("ELEMENT %016llx:%d %c %016llx %02x %016llx lo=%02x %d\n",
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239 cursor->node->node_offset,
240 cursor->index,
241 (elm[0].leaf.base.btype ?
242 elm[0].leaf.base.btype : '?'),
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243 elm[0].leaf.base.obj_id,
244 elm[0].leaf.base.rec_type,
245 elm[0].leaf.base.key,
2f85fa4d 246 elm[0].leaf.base.localization,
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247 r
248 );
249 }
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250 if (r < 0) {
251 error = ENOENT;
252 break;
253 }
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254
255 /*
256 * We support both end-inclusive and
257 * end-exclusive searches.
258 */
259 if (r == 0 &&
260 (cursor->flags & HAMMER_CURSOR_END_INCLUSIVE) == 0) {
261 error = ENOENT;
262 break;
263 }
264
fe7678ee
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265 switch(elm->leaf.base.btype) {
266 case HAMMER_BTREE_TYPE_RECORD:
267 if ((cursor->flags & HAMMER_CURSOR_ASOF) &&
268 hammer_btree_chkts(cursor->asof, &elm->base)) {
269 ++cursor->index;
270 continue;
271 }
272 break;
fe7678ee
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273 default:
274 error = EINVAL;
275 break;
d26d0ae9 276 }
fe7678ee
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277 if (error)
278 break;
66325755 279 }
46fe7ae1
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280 /*
281 * node pointer invalid after loop
282 */
66325755
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283
284 /*
d26d0ae9 285 * Return entry
66325755 286 */
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287 if (hammer_debug_btree) {
288 int i = cursor->index;
289 hammer_btree_elm_t elm = &cursor->node->ondisk->elms[i];
2f85fa4d 290 kprintf("ITERATE %p:%d %016llx %02x %016llx lo=%02x\n",
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291 cursor->node, i,
292 elm->internal.base.obj_id,
293 elm->internal.base.rec_type,
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294 elm->internal.base.key,
295 elm->internal.base.localization
b3deaf57
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296 );
297 }
d26d0ae9 298 return(0);
427e5fc6 299 }
66325755 300 return(error);
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301}
302
32c90105
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303/*
304 * Iterate in the reverse direction. This is used by the pruning code to
305 * avoid overlapping records.
306 */
307int
308hammer_btree_iterate_reverse(hammer_cursor_t cursor)
309{
310 hammer_node_ondisk_t node;
311 hammer_btree_elm_t elm;
312 int error;
313 int r;
314 int s;
315
316 /*
317 * Skip past the current record. For various reasons the cursor
318 * may end up set to -1 or set to point at the end of the current
319 * node. These cases must be addressed.
320 */
321 node = cursor->node->ondisk;
322 if (node == NULL)
323 return(ENOENT);
324 if (cursor->index != -1 &&
325 (cursor->flags & HAMMER_CURSOR_ATEDISK)) {
326 --cursor->index;
327 }
328 if (cursor->index == cursor->node->ondisk->count)
329 --cursor->index;
330
331 /*
332 * Loop until an element is found or we are done.
333 */
334 for (;;) {
335 /*
336 * We iterate up the tree and then index over one element
337 * while we are at the last element in the current node.
32c90105
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338 */
339 if (cursor->index == -1) {
340 error = hammer_cursor_up(cursor);
341 if (error) {
342 cursor->index = 0; /* sanity */
343 break;
344 }
345 /* reload stale pointer */
346 node = cursor->node->ondisk;
347 KKASSERT(cursor->index != node->count);
348 --cursor->index;
349 continue;
350 }
351
352 /*
353 * Check internal or leaf element. Determine if the record
354 * at the cursor has gone beyond the end of our range.
355 *
47197d71 356 * We recurse down through internal nodes.
32c90105
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357 */
358 KKASSERT(cursor->index != node->count);
359 if (node->type == HAMMER_BTREE_TYPE_INTERNAL) {
360 elm = &node->elms[cursor->index];
361 r = hammer_btree_cmp(&cursor->key_end, &elm[0].base);
362 s = hammer_btree_cmp(&cursor->key_beg, &elm[1].base);
363 if (hammer_debug_btree) {
2f85fa4d 364 kprintf("BRACKETL %016llx[%d] %016llx %02x %016llx lo=%02x %d\n",
32c90105
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365 cursor->node->node_offset,
366 cursor->index,
367 elm[0].internal.base.obj_id,
368 elm[0].internal.base.rec_type,
369 elm[0].internal.base.key,
2f85fa4d 370 elm[0].internal.base.localization,
32c90105
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371 r
372 );
2f85fa4d 373 kprintf("BRACKETR %016llx[%d] %016llx %02x %016llx lo=%02x %d\n",
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374 cursor->node->node_offset,
375 cursor->index + 1,
376 elm[1].internal.base.obj_id,
377 elm[1].internal.base.rec_type,
378 elm[1].internal.base.key,
2f85fa4d 379 elm[1].internal.base.localization,
32c90105
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380 s
381 );
382 }
383
384 if (s >= 0) {
385 error = ENOENT;
386 break;
387 }
388 KKASSERT(r >= 0);
389
390 /*
f36a9737 391 * Better not be zero
32c90105 392 */
f36a9737
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393 KKASSERT(elm->internal.subtree_offset != 0);
394
395 error = hammer_cursor_down(cursor);
396 if (error)
397 break;
398 KKASSERT(cursor->index == 0);
32c90105
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399 /* reload stale pointer */
400 node = cursor->node->ondisk;
f36a9737
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401
402 /* this can assign -1 if the leaf was empty */
403 cursor->index = node->count - 1;
32c90105
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404 continue;
405 } else {
406 elm = &node->elms[cursor->index];
407 s = hammer_btree_cmp(&cursor->key_beg, &elm->base);
408 if (hammer_debug_btree) {
2f85fa4d 409 kprintf("ELEMENT %016llx:%d %c %016llx %02x %016llx lo=%02x %d\n",
32c90105
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410 cursor->node->node_offset,
411 cursor->index,
412 (elm[0].leaf.base.btype ?
413 elm[0].leaf.base.btype : '?'),
414 elm[0].leaf.base.obj_id,
415 elm[0].leaf.base.rec_type,
416 elm[0].leaf.base.key,
2f85fa4d 417 elm[0].leaf.base.localization,
32c90105
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418 s
419 );
420 }
421 if (s > 0) {
422 error = ENOENT;
423 break;
424 }
425
426 switch(elm->leaf.base.btype) {
427 case HAMMER_BTREE_TYPE_RECORD:
428 if ((cursor->flags & HAMMER_CURSOR_ASOF) &&
429 hammer_btree_chkts(cursor->asof, &elm->base)) {
430 --cursor->index;
431 continue;
432 }
433 break;
32c90105
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434 default:
435 error = EINVAL;
436 break;
437 }
438 if (error)
439 break;
440 }
441 /*
442 * node pointer invalid after loop
443 */
444
445 /*
446 * Return entry
447 */
448 if (hammer_debug_btree) {
449 int i = cursor->index;
450 hammer_btree_elm_t elm = &cursor->node->ondisk->elms[i];
2f85fa4d 451 kprintf("ITERATE %p:%d %016llx %02x %016llx lo=%02x\n",
32c90105
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452 cursor->node, i,
453 elm->internal.base.obj_id,
454 elm->internal.base.rec_type,
2f85fa4d
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455 elm->internal.base.key,
456 elm->internal.base.localization
32c90105
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457 );
458 }
459 return(0);
460 }
461 return(error);
462}
463
427e5fc6 464/*
8cd0a023 465 * Lookup cursor->key_beg. 0 is returned on success, ENOENT if the entry
6a37e7e4
MD
466 * could not be found, EDEADLK if inserting and a retry is needed, and a
467 * fatal error otherwise. When retrying, the caller must terminate the
eaeff70d 468 * cursor and reinitialize it. EDEADLK cannot be returned if not inserting.
8cd0a023
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469 *
470 * The cursor is suitably positioned for a deletion on success, and suitably
eaeff70d
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471 * positioned for an insertion on ENOENT if HAMMER_CURSOR_INSERT was
472 * specified.
427e5fc6 473 *
47197d71 474 * The cursor may begin anywhere, the search will traverse the tree in
8cd0a023 475 * either direction to locate the requested element.
eaeff70d
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476 *
477 * Most of the logic implementing historical searches is handled here. We
9582c7da
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478 * do an initial lookup with create_tid set to the asof TID. Due to the
479 * way records are laid out, a backwards iteration may be required if
eaeff70d
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480 * ENOENT is returned to locate the historical record. Here's the
481 * problem:
482 *
9582c7da 483 * create_tid: 10 15 20
eaeff70d
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484 * LEAF1 LEAF2
485 * records: (11) (18)
486 *
9582c7da
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487 * Lets say we want to do a lookup AS-OF timestamp 17. We will traverse
488 * LEAF2 but the only record in LEAF2 has a create_tid of 18, which is
489 * not visible and thus causes ENOENT to be returned. We really need
490 * to check record 11 in LEAF1. If it also fails then the search fails
491 * (e.g. it might represent the range 11-16 and thus still not match our
f36a9737
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492 * AS-OF timestamp of 17). Note that LEAF1 could be empty, requiring
493 * further iterations.
b33e2cc0 494 *
9582c7da
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495 * If this case occurs btree_search() will set HAMMER_CURSOR_CREATE_CHECK
496 * and the cursor->create_check TID if an iteration might be needed.
497 * In the above example create_check would be set to 14.
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498 */
499int
8cd0a023 500hammer_btree_lookup(hammer_cursor_t cursor)
427e5fc6 501{
66325755
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502 int error;
503
d5530d22 504 if (cursor->flags & HAMMER_CURSOR_ASOF) {
eaeff70d 505 KKASSERT((cursor->flags & HAMMER_CURSOR_INSERT) == 0);
9582c7da 506 cursor->key_beg.create_tid = cursor->asof;
eaeff70d 507 for (;;) {
9582c7da 508 cursor->flags &= ~HAMMER_CURSOR_CREATE_CHECK;
d5530d22 509 error = btree_search(cursor, 0);
b33e2cc0 510 if (error != ENOENT ||
9582c7da 511 (cursor->flags & HAMMER_CURSOR_CREATE_CHECK) == 0) {
b33e2cc0
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512 /*
513 * Stop if no error.
514 * Stop if error other then ENOENT.
515 * Stop if ENOENT and not special case.
516 */
eaeff70d
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517 break;
518 }
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519 if (hammer_debug_btree) {
520 kprintf("CREATE_CHECK %016llx\n",
521 cursor->create_check);
522 }
9582c7da 523 cursor->key_beg.create_tid = cursor->create_check;
eaeff70d
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524 /* loop */
525 }
d5530d22
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526 } else {
527 error = btree_search(cursor, 0);
528 }
8cd0a023
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529 if (error == 0 && cursor->flags)
530 error = hammer_btree_extract(cursor, cursor->flags);
66325755
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531 return(error);
532}
533
d26d0ae9
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534/*
535 * Execute the logic required to start an iteration. The first record
536 * located within the specified range is returned and iteration control
537 * flags are adjusted for successive hammer_btree_iterate() calls.
538 */
539int
540hammer_btree_first(hammer_cursor_t cursor)
541{
542 int error;
543
544 error = hammer_btree_lookup(cursor);
545 if (error == ENOENT) {
546 cursor->flags &= ~HAMMER_CURSOR_ATEDISK;
547 error = hammer_btree_iterate(cursor);
548 }
549 cursor->flags |= HAMMER_CURSOR_ATEDISK;
550 return(error);
551}
552
32c90105
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553/*
554 * Similarly but for an iteration in the reverse direction.
814387f6
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555 *
556 * Set ATEDISK when iterating backwards to skip the current entry,
557 * which after an ENOENT lookup will be pointing beyond our end point.
32c90105
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558 */
559int
560hammer_btree_last(hammer_cursor_t cursor)
561{
562 struct hammer_base_elm save;
563 int error;
564
565 save = cursor->key_beg;
566 cursor->key_beg = cursor->key_end;
567 error = hammer_btree_lookup(cursor);
568 cursor->key_beg = save;
569 if (error == ENOENT ||
570 (cursor->flags & HAMMER_CURSOR_END_INCLUSIVE) == 0) {
814387f6 571 cursor->flags |= HAMMER_CURSOR_ATEDISK;
32c90105
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572 error = hammer_btree_iterate_reverse(cursor);
573 }
574 cursor->flags |= HAMMER_CURSOR_ATEDISK;
575 return(error);
576}
577
8cd0a023
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578/*
579 * Extract the record and/or data associated with the cursor's current
580 * position. Any prior record or data stored in the cursor is replaced.
581 * The cursor must be positioned at a leaf node.
582 *
47197d71 583 * NOTE: All extractions occur at the leaf of the B-Tree.
8cd0a023 584 */
66325755 585int
8cd0a023 586hammer_btree_extract(hammer_cursor_t cursor, int flags)
66325755 587{
47197d71 588 hammer_mount_t hmp;
8cd0a023
MD
589 hammer_node_ondisk_t node;
590 hammer_btree_elm_t elm;
47197d71 591 hammer_off_t data_off;
19619882 592 int32_t data_len;
427e5fc6 593 int error;
427e5fc6 594
8cd0a023 595 /*
427e5fc6
MD
596 * The case where the data reference resolves to the same buffer
597 * as the record reference must be handled.
598 */
8cd0a023 599 node = cursor->node->ondisk;
8cd0a023 600 elm = &node->elms[cursor->index];
40043e7f
MD
601 cursor->data = NULL;
602 hmp = cursor->node->hmp;
47197d71 603 flags |= cursor->flags & HAMMER_CURSOR_DATAEXTOK;
66325755 604
d26d0ae9 605 /*
fe7678ee 606 * There is nothing to extract for an internal element.
d26d0ae9 607 */
fe7678ee
MD
608 if (node->type == HAMMER_BTREE_TYPE_INTERNAL)
609 return(EINVAL);
610
47197d71
MD
611 /*
612 * Only record types have data.
613 */
fe7678ee 614 KKASSERT(node->type == HAMMER_BTREE_TYPE_LEAF);
11ad5ade 615 cursor->leaf = &elm->leaf;
47197d71
MD
616 if (elm->leaf.base.btype != HAMMER_BTREE_TYPE_RECORD)
617 flags &= ~HAMMER_CURSOR_GET_DATA;
618 data_off = elm->leaf.data_offset;
19619882 619 data_len = elm->leaf.data_len;
47197d71
MD
620 if (data_off == 0)
621 flags &= ~HAMMER_CURSOR_GET_DATA;
d26d0ae9 622
11ad5ade
MD
623 error = 0;
624 if ((flags & HAMMER_CURSOR_GET_DATA)) {
625 /*
626 * Data and record are in different buffers.
627 */
628 cursor->data = hammer_bread(hmp, data_off, &error,
40043e7f 629 &cursor->data_buffer);
19619882
MD
630 KKASSERT(data_len >= 0 && data_len <= HAMMER_BUFSIZE);
631 if (data_len &&
632 crc32(cursor->data, data_len) != elm->leaf.data_crc) {
633 Debugger("CRC FAILED: DATA");
634 }
427e5fc6
MD
635 }
636 return(error);
637}
638
639
640/*
8cd0a023
MD
641 * Insert a leaf element into the B-Tree at the current cursor position.
642 * The cursor is positioned such that the element at and beyond the cursor
643 * are shifted to make room for the new record.
644 *
a89aec1b 645 * The caller must call hammer_btree_lookup() with the HAMMER_CURSOR_INSERT
8cd0a023
MD
646 * flag set and that call must return ENOENT before this function can be
647 * called.
648 *
d36ec43b 649 * The caller may depend on the cursor's exclusive lock after return to
1f07f686 650 * interlock frontend visibility (see HAMMER_RECF_CONVERT_DELETE).
d36ec43b 651 *
8cd0a023 652 * ENOSPC is returned if there is no room to insert a new record.
427e5fc6
MD
653 */
654int
11ad5ade 655hammer_btree_insert(hammer_cursor_t cursor, hammer_btree_leaf_elm_t elm)
427e5fc6 656{
8cd0a023 657 hammer_node_ondisk_t node;
427e5fc6 658 int i;
6a37e7e4
MD
659 int error;
660
661 if ((error = hammer_cursor_upgrade(cursor)) != 0)
662 return(error);
427e5fc6 663
427e5fc6
MD
664 /*
665 * Insert the element at the leaf node and update the count in the
666 * parent. It is possible for parent to be NULL, indicating that
47197d71
MD
667 * the filesystem's ROOT B-Tree node is a leaf itself, which is
668 * possible. The root inode can never be deleted so the leaf should
669 * never be empty.
427e5fc6
MD
670 *
671 * Remember that the right-hand boundary is not included in the
672 * count.
673 */
36f82b23 674 hammer_modify_node_all(cursor->trans, cursor->node);
8cd0a023 675 node = cursor->node->ondisk;
427e5fc6 676 i = cursor->index;
fe7678ee 677 KKASSERT(elm->base.btype != 0);
8cd0a023
MD
678 KKASSERT(node->type == HAMMER_BTREE_TYPE_LEAF);
679 KKASSERT(node->count < HAMMER_BTREE_LEAF_ELMS);
680 if (i != node->count) {
681 bcopy(&node->elms[i], &node->elms[i+1],
682 (node->count - i) * sizeof(*elm));
683 }
11ad5ade 684 node->elms[i].leaf = *elm;
8cd0a023 685 ++node->count;
10a5d1ba 686 hammer_modify_node_done(cursor->node);
427e5fc6 687
eaeff70d 688 /*
47197d71 689 * Debugging sanity checks.
eaeff70d 690 */
11ad5ade
MD
691 KKASSERT(hammer_btree_cmp(cursor->left_bound, &elm->base) <= 0);
692 KKASSERT(hammer_btree_cmp(cursor->right_bound, &elm->base) > 0);
eaeff70d 693 if (i) {
11ad5ade 694 KKASSERT(hammer_btree_cmp(&node->elms[i-1].leaf.base, &elm->base) < 0);
eaeff70d 695 }
b3deaf57 696 if (i != node->count - 1)
11ad5ade 697 KKASSERT(hammer_btree_cmp(&node->elms[i+1].leaf.base, &elm->base) > 0);
b3deaf57 698
427e5fc6
MD
699 return(0);
700}
701
702/*
fe7678ee 703 * Delete a record from the B-Tree at the current cursor position.
8cd0a023
MD
704 * The cursor is positioned such that the current element is the one
705 * to be deleted.
706 *
195c19a1
MD
707 * On return the cursor will be positioned after the deleted element and
708 * MAY point to an internal node. It will be suitable for the continuation
709 * of an iteration but not for an insertion or deletion.
8cd0a023 710 *
195c19a1 711 * Deletions will attempt to partially rebalance the B-Tree in an upward
f36a9737
MD
712 * direction, but will terminate rather then deadlock. Empty internal nodes
713 * are never allowed by a deletion which deadlocks may end up giving us an
714 * empty leaf. The pruner will clean up and rebalance the tree.
46fe7ae1
MD
715 *
716 * This function can return EDEADLK, requiring the caller to retry the
717 * operation after clearing the deadlock.
427e5fc6
MD
718 */
719int
8cd0a023 720hammer_btree_delete(hammer_cursor_t cursor)
427e5fc6 721{
8cd0a023
MD
722 hammer_node_ondisk_t ondisk;
723 hammer_node_t node;
724 hammer_node_t parent;
8cd0a023 725 int error;
427e5fc6
MD
726 int i;
727
6a37e7e4
MD
728 if ((error = hammer_cursor_upgrade(cursor)) != 0)
729 return(error);
730
427e5fc6 731 /*
8cd0a023 732 * Delete the element from the leaf node.
427e5fc6 733 *
8cd0a023 734 * Remember that leaf nodes do not have boundaries.
427e5fc6 735 */
8cd0a023
MD
736 node = cursor->node;
737 ondisk = node->ondisk;
427e5fc6
MD
738 i = cursor->index;
739
8cd0a023 740 KKASSERT(ondisk->type == HAMMER_BTREE_TYPE_LEAF);
fe7678ee 741 KKASSERT(i >= 0 && i < ondisk->count);
36f82b23 742 hammer_modify_node_all(cursor->trans, node);
8cd0a023
MD
743 if (i + 1 != ondisk->count) {
744 bcopy(&ondisk->elms[i+1], &ondisk->elms[i],
745 (ondisk->count - i - 1) * sizeof(ondisk->elms[0]));
746 }
747 --ondisk->count;
10a5d1ba 748 hammer_modify_node_done(node);
fe7678ee
MD
749
750 /*
751 * Validate local parent
752 */
753 if (ondisk->parent) {
8cd0a023 754 parent = cursor->parent;
fe7678ee
MD
755
756 KKASSERT(parent != NULL);
757 KKASSERT(parent->node_offset == ondisk->parent);
427e5fc6 758 }
427e5fc6 759
8cd0a023 760 /*
fe7678ee 761 * If the leaf becomes empty it must be detached from the parent,
47197d71 762 * potentially recursing through to the filesystem root.
195c19a1
MD
763 *
764 * This may reposition the cursor at one of the parent's of the
765 * current node.
6a37e7e4
MD
766 *
767 * Ignore deadlock errors, that simply means that btree_remove
f36a9737 768 * was unable to recurse and had to leave us with an empty leaf.
8cd0a023 769 */
b3deaf57 770 KKASSERT(cursor->index <= ondisk->count);
8cd0a023 771 if (ondisk->count == 0) {
f36a9737 772 error = btree_remove(cursor);
6a37e7e4
MD
773 if (error == EDEADLK)
774 error = 0;
8cd0a023 775 } else {
8cd0a023
MD
776 error = 0;
777 }
eaeff70d
MD
778 KKASSERT(cursor->parent == NULL ||
779 cursor->parent_index < cursor->parent->ondisk->count);
8cd0a023
MD
780 return(error);
781}
427e5fc6
MD
782
783/*
8cd0a023
MD
784 * PRIMAY B-TREE SEARCH SUPPORT PROCEDURE
785 *
47197d71 786 * Search the filesystem B-Tree for cursor->key_beg, return the matching node.
8cd0a023 787 *
d26d0ae9
MD
788 * The search can begin ANYWHERE in the B-Tree. As a first step the search
789 * iterates up the tree as necessary to properly position itself prior to
790 * actually doing the sarch.
791 *
8cd0a023 792 * INSERTIONS: The search will split full nodes and leaves on its way down
d26d0ae9
MD
793 * and guarentee that the leaf it ends up on is not full. If we run out
794 * of space the search continues to the leaf (to position the cursor for
795 * the spike), but ENOSPC is returned.
427e5fc6 796 *
fbc6e32a
MD
797 * The search is only guarenteed to end up on a leaf if an error code of 0
798 * is returned, or if inserting and an error code of ENOENT is returned.
d26d0ae9 799 * Otherwise it can stop at an internal node. On success a search returns
47197d71 800 * a leaf node.
eaeff70d
MD
801 *
802 * COMPLEXITY WARNING! This is the core B-Tree search code for the entire
803 * filesystem, and it is not simple code. Please note the following facts:
804 *
805 * - Internal node recursions have a boundary on the left AND right. The
9582c7da 806 * right boundary is non-inclusive. The create_tid is a generic part
eaeff70d
MD
807 * of the key for internal nodes.
808 *
47197d71 809 * - Leaf nodes contain terminal elements only now.
eaeff70d
MD
810 *
811 * - Filesystem lookups typically set HAMMER_CURSOR_ASOF, indicating a
b33e2cc0
MD
812 * historical search. ASOF and INSERT are mutually exclusive. When
813 * doing an as-of lookup btree_search() checks for a right-edge boundary
9582c7da
MD
814 * case. If while recursing down the left-edge differs from the key
815 * by ONLY its create_tid, HAMMER_CURSOR_CREATE_CHECK is set along
816 * with cursor->create_check. This is used by btree_lookup() to iterate.
817 * The iteration backwards because as-of searches can wind up going
b33e2cc0 818 * down the wrong branch of the B-Tree.
427e5fc6 819 */
8cd0a023 820static
427e5fc6 821int
8cd0a023 822btree_search(hammer_cursor_t cursor, int flags)
427e5fc6 823{
8cd0a023 824 hammer_node_ondisk_t node;
61aeeb33 825 hammer_btree_elm_t elm;
8cd0a023 826 int error;
d26d0ae9 827 int enospc = 0;
8cd0a023
MD
828 int i;
829 int r;
b33e2cc0 830 int s;
8cd0a023
MD
831
832 flags |= cursor->flags;
833
b3deaf57 834 if (hammer_debug_btree) {
2f85fa4d 835 kprintf("SEARCH %016llx[%d] %016llx %02x key=%016llx cre=%016llx lo=%02x (td = %p)\n",
eaeff70d
MD
836 cursor->node->node_offset,
837 cursor->index,
b3deaf57
MD
838 cursor->key_beg.obj_id,
839 cursor->key_beg.rec_type,
d113fda1 840 cursor->key_beg.key,
a84a197d 841 cursor->key_beg.create_tid,
2f85fa4d 842 cursor->key_beg.localization,
a84a197d 843 curthread
b3deaf57 844 );
a84a197d
MD
845 if (cursor->parent)
846 kprintf("SEARCHP %016llx[%d] (%016llx/%016llx %016llx/%016llx) (%p/%p %p/%p)\n",
847 cursor->parent->node_offset, cursor->parent_index,
848 cursor->left_bound->obj_id,
849 cursor->parent->ondisk->elms[cursor->parent_index].internal.base.obj_id,
850 cursor->right_bound->obj_id,
851 cursor->parent->ondisk->elms[cursor->parent_index+1].internal.base.obj_id,
852 cursor->left_bound,
853 &cursor->parent->ondisk->elms[cursor->parent_index],
854 cursor->right_bound,
855 &cursor->parent->ondisk->elms[cursor->parent_index+1]
856 );
b3deaf57
MD
857 }
858
8cd0a023
MD
859 /*
860 * Move our cursor up the tree until we find a node whos range covers
47197d71 861 * the key we are trying to locate.
8cd0a023
MD
862 *
863 * The left bound is inclusive, the right bound is non-inclusive.
47197d71 864 * It is ok to cursor up too far.
8cd0a023 865 */
b33e2cc0
MD
866 for (;;) {
867 r = hammer_btree_cmp(&cursor->key_beg, cursor->left_bound);
868 s = hammer_btree_cmp(&cursor->key_beg, cursor->right_bound);
869 if (r >= 0 && s < 0)
870 break;
9944ae54 871 KKASSERT(cursor->parent);
6a37e7e4 872 error = hammer_cursor_up(cursor);
8cd0a023
MD
873 if (error)
874 goto done;
427e5fc6 875 }
427e5fc6 876
b33e2cc0
MD
877 /*
878 * The delete-checks below are based on node, not parent. Set the
879 * initial delete-check based on the parent.
880 */
9582c7da
MD
881 if (r == 1) {
882 KKASSERT(cursor->left_bound->create_tid != 1);
883 cursor->create_check = cursor->left_bound->create_tid - 1;
884 cursor->flags |= HAMMER_CURSOR_CREATE_CHECK;
b33e2cc0
MD
885 }
886
8cd0a023 887 /*
47197d71 888 * We better have ended up with a node somewhere.
8cd0a023 889 */
47197d71 890 KKASSERT(cursor->node != NULL);
8cd0a023
MD
891
892 /*
893 * If we are inserting we can't start at a full node if the parent
894 * is also full (because there is no way to split the node),
b33e2cc0 895 * continue running up the tree until the requirement is satisfied
47197d71 896 * or we hit the root of the filesystem.
9582c7da
MD
897 *
898 * (If inserting we aren't doing an as-of search so we don't have
899 * to worry about create_check).
8cd0a023 900 */
61aeeb33 901 while ((flags & HAMMER_CURSOR_INSERT) && enospc == 0) {
eaeff70d
MD
902 if (cursor->node->ondisk->type == HAMMER_BTREE_TYPE_INTERNAL) {
903 if (btree_node_is_full(cursor->node->ondisk) == 0)
904 break;
905 } else {
47197d71 906 if (btree_node_is_full(cursor->node->ondisk) ==0)
eaeff70d
MD
907 break;
908 }
b33e2cc0
MD
909 if (cursor->node->ondisk->parent == 0 ||
910 cursor->parent->ondisk->count != HAMMER_BTREE_INT_ELMS) {
8cd0a023 911 break;
b33e2cc0 912 }
6a37e7e4 913 error = hammer_cursor_up(cursor);
47197d71 914 /* node may have become stale */
8cd0a023
MD
915 if (error)
916 goto done;
427e5fc6 917 }
427e5fc6 918
8cd0a023
MD
919 /*
920 * Push down through internal nodes to locate the requested key.
921 */
8cd0a023
MD
922 node = cursor->node->ondisk;
923 while (node->type == HAMMER_BTREE_TYPE_INTERNAL) {
8cd0a023
MD
924 /*
925 * Scan the node to find the subtree index to push down into.
fbc6e32a 926 * We go one-past, then back-up.
d113fda1 927 *
fe7678ee
MD
928 * We must proactively remove deleted elements which may
929 * have been left over from a deadlocked btree_remove().
930 *
eaeff70d 931 * The left and right boundaries are included in the loop
d5530d22 932 * in order to detect edge cases.
9944ae54 933 *
9582c7da 934 * If the separator only differs by create_tid (r == 1)
eaeff70d
MD
935 * and we are doing an as-of search, we may end up going
936 * down a branch to the left of the one containing the
937 * desired key. This requires numerous special cases.
8cd0a023 938 */
47637bff 939 ++hammer_stats_btree_iterations;
46fe7ae1 940 if (hammer_debug_btree) {
47197d71 941 kprintf("SEARCH-I %016llx count=%d\n",
46fe7ae1
MD
942 cursor->node->node_offset,
943 node->count);
944 }
9944ae54 945 for (i = 0; i <= node->count; ++i) {
61aeeb33
MD
946 elm = &node->elms[i];
947 r = hammer_btree_cmp(&cursor->key_beg, &elm->base);
b33e2cc0
MD
948 if (hammer_debug_btree > 2) {
949 kprintf(" IELM %p %d r=%d\n",
950 &node->elms[i], i, r);
951 }
9582c7da 952 if (r < 0)
8cd0a023 953 break;
9582c7da
MD
954 if (r == 1) {
955 KKASSERT(elm->base.create_tid != 1);
956 cursor->create_check = elm->base.create_tid - 1;
957 cursor->flags |= HAMMER_CURSOR_CREATE_CHECK;
b33e2cc0 958 }
8cd0a023 959 }
eaeff70d 960 if (hammer_debug_btree) {
46fe7ae1
MD
961 kprintf("SEARCH-I preI=%d/%d r=%d\n",
962 i, node->count, r);
eaeff70d 963 }
8cd0a023
MD
964
965 /*
9944ae54
MD
966 * These cases occur when the parent's idea of the boundary
967 * is wider then the child's idea of the boundary, and
968 * require special handling. If not inserting we can
969 * terminate the search early for these cases but the
970 * child's boundaries cannot be unconditionally modified.
8cd0a023 971 */
fbc6e32a 972 if (i == 0) {
9944ae54
MD
973 /*
974 * If i == 0 the search terminated to the LEFT of the
975 * left_boundary but to the RIGHT of the parent's left
976 * boundary.
977 */
fbc6e32a 978 u_int8_t save;
d26d0ae9 979
eaeff70d
MD
980 elm = &node->elms[0];
981
982 /*
983 * If we aren't inserting we can stop here.
984 */
11ad5ade
MD
985 if ((flags & (HAMMER_CURSOR_INSERT |
986 HAMMER_CURSOR_PRUNING)) == 0) {
fbc6e32a
MD
987 cursor->index = 0;
988 return(ENOENT);
989 }
9944ae54 990
d5530d22
MD
991 /*
992 * Correct a left-hand boundary mismatch.
6a37e7e4 993 *
f36a9737
MD
994 * We can only do this if we can upgrade the lock,
995 * and synchronized as a background cursor (i.e.
996 * inserting or pruning).
10a5d1ba
MD
997 *
998 * WARNING: We can only do this if inserting, i.e.
999 * we are running on the backend.
d5530d22 1000 */
eaeff70d
MD
1001 if ((error = hammer_cursor_upgrade(cursor)) != 0)
1002 return(error);
10a5d1ba 1003 KKASSERT(cursor->flags & HAMMER_CURSOR_BACKEND);
c9b9e29d
MD
1004 hammer_modify_node_field(cursor->trans, cursor->node,
1005 elms[0]);
fe7678ee 1006 save = node->elms[0].base.btype;
d5530d22 1007 node->elms[0].base = *cursor->left_bound;
fe7678ee 1008 node->elms[0].base.btype = save;
10a5d1ba 1009 hammer_modify_node_done(cursor->node);
9944ae54 1010 } else if (i == node->count + 1) {
d26d0ae9 1011 /*
9944ae54
MD
1012 * If i == node->count + 1 the search terminated to
1013 * the RIGHT of the right boundary but to the LEFT
eaeff70d
MD
1014 * of the parent's right boundary. If we aren't
1015 * inserting we can stop here.
d113fda1 1016 *
9944ae54
MD
1017 * Note that the last element in this case is
1018 * elms[i-2] prior to adjustments to 'i'.
d26d0ae9 1019 */
9944ae54 1020 --i;
11ad5ade
MD
1021 if ((flags & (HAMMER_CURSOR_INSERT |
1022 HAMMER_CURSOR_PRUNING)) == 0) {
9944ae54 1023 cursor->index = i;
eaeff70d 1024 return (ENOENT);
d26d0ae9
MD
1025 }
1026
d5530d22
MD
1027 /*
1028 * Correct a right-hand boundary mismatch.
1029 * (actual push-down record is i-2 prior to
1030 * adjustments to i).
6a37e7e4 1031 *
f36a9737
MD
1032 * We can only do this if we can upgrade the lock,
1033 * and synchronized as a background cursor (i.e.
1034 * inserting or pruning).
10a5d1ba
MD
1035 *
1036 * WARNING: We can only do this if inserting, i.e.
1037 * we are running on the backend.
d5530d22 1038 */
eaeff70d
MD
1039 if ((error = hammer_cursor_upgrade(cursor)) != 0)
1040 return(error);
9944ae54 1041 elm = &node->elms[i];
10a5d1ba 1042 KKASSERT(cursor->flags & HAMMER_CURSOR_BACKEND);
36f82b23
MD
1043 hammer_modify_node(cursor->trans, cursor->node,
1044 &elm->base, sizeof(elm->base));
d5530d22 1045 elm->base = *cursor->right_bound;
10a5d1ba 1046 hammer_modify_node_done(cursor->node);
d5530d22 1047 --i;
fbc6e32a
MD
1048 } else {
1049 /*
9944ae54
MD
1050 * The push-down index is now i - 1. If we had
1051 * terminated on the right boundary this will point
1052 * us at the last element.
fbc6e32a
MD
1053 */
1054 --i;
1055 }
8cd0a023 1056 cursor->index = i;
6a37e7e4 1057 elm = &node->elms[i];
8cd0a023 1058
b3deaf57 1059 if (hammer_debug_btree) {
47197d71 1060 kprintf("RESULT-I %016llx[%d] %016llx %02x "
2f85fa4d 1061 "key=%016llx cre=%016llx lo=%02x\n",
eaeff70d
MD
1062 cursor->node->node_offset,
1063 i,
b3deaf57
MD
1064 elm->internal.base.obj_id,
1065 elm->internal.base.rec_type,
d113fda1 1066 elm->internal.base.key,
2f85fa4d
MD
1067 elm->internal.base.create_tid,
1068 elm->internal.base.localization
b3deaf57
MD
1069 );
1070 }
1071
6a37e7e4 1072 /*
f36a9737 1073 * We better have a valid subtree offset.
6a37e7e4 1074 */
f36a9737 1075 KKASSERT(elm->internal.subtree_offset != 0);
6a37e7e4 1076
8cd0a023
MD
1077 /*
1078 * Handle insertion and deletion requirements.
1079 *
1080 * If inserting split full nodes. The split code will
1081 * adjust cursor->node and cursor->index if the current
1082 * index winds up in the new node.
61aeeb33 1083 *
9944ae54
MD
1084 * If inserting and a left or right edge case was detected,
1085 * we cannot correct the left or right boundary and must
1086 * prepend and append an empty leaf node in order to make
1087 * the boundary correction.
1088 *
61aeeb33
MD
1089 * If we run out of space we set enospc and continue on
1090 * to a leaf to provide the spike code with a good point
47197d71 1091 * of entry.
8cd0a023 1092 */
61aeeb33 1093 if ((flags & HAMMER_CURSOR_INSERT) && enospc == 0) {
fe7678ee 1094 if (btree_node_is_full(node)) {
8cd0a023 1095 error = btree_split_internal(cursor);
d26d0ae9
MD
1096 if (error) {
1097 if (error != ENOSPC)
1098 goto done;
1099 enospc = 1;
d26d0ae9 1100 }
8cd0a023
MD
1101 /*
1102 * reload stale pointers
1103 */
1104 i = cursor->index;
1105 node = cursor->node->ondisk;
1106 }
d26d0ae9 1107 }
427e5fc6
MD
1108
1109 /*
8cd0a023 1110 * Push down (push into new node, existing node becomes
d26d0ae9 1111 * the parent) and continue the search.
427e5fc6 1112 */
8cd0a023 1113 error = hammer_cursor_down(cursor);
47197d71 1114 /* node may have become stale */
8cd0a023
MD
1115 if (error)
1116 goto done;
1117 node = cursor->node->ondisk;
427e5fc6 1118 }
427e5fc6 1119
8cd0a023
MD
1120 /*
1121 * We are at a leaf, do a linear search of the key array.
d26d0ae9
MD
1122 *
1123 * On success the index is set to the matching element and 0
1124 * is returned.
1125 *
1126 * On failure the index is set to the insertion point and ENOENT
1127 * is returned.
8cd0a023
MD
1128 *
1129 * Boundaries are not stored in leaf nodes, so the index can wind
1130 * up to the left of element 0 (index == 0) or past the end of
f36a9737
MD
1131 * the array (index == node->count). It is also possible that the
1132 * leaf might be empty.
8cd0a023 1133 */
47637bff 1134 ++hammer_stats_btree_iterations;
fe7678ee 1135 KKASSERT (node->type == HAMMER_BTREE_TYPE_LEAF);
8cd0a023 1136 KKASSERT(node->count <= HAMMER_BTREE_LEAF_ELMS);
46fe7ae1 1137 if (hammer_debug_btree) {
47197d71 1138 kprintf("SEARCH-L %016llx count=%d\n",
46fe7ae1
MD
1139 cursor->node->node_offset,
1140 node->count);
1141 }
8cd0a023
MD
1142
1143 for (i = 0; i < node->count; ++i) {
fe7678ee
MD
1144 elm = &node->elms[i];
1145
1146 r = hammer_btree_cmp(&cursor->key_beg, &elm->leaf.base);
427e5fc6 1147
d5530d22
MD
1148 if (hammer_debug_btree > 1)
1149 kprintf(" ELM %p %d r=%d\n", &node->elms[i], i, r);
1150
427e5fc6 1151 /*
fe7678ee 1152 * We are at a record element. Stop if we've flipped past
9582c7da
MD
1153 * key_beg, not counting the create_tid test. Allow the
1154 * r == 1 case (key_beg > element but differs only by its
1155 * create_tid) to fall through to the AS-OF check.
427e5fc6 1156 */
fe7678ee
MD
1157 KKASSERT (elm->leaf.base.btype == HAMMER_BTREE_TYPE_RECORD);
1158
9582c7da 1159 if (r < 0)
d5530d22 1160 goto failed;
9582c7da 1161 if (r > 1)
d5530d22 1162 continue;
427e5fc6 1163
66325755 1164 /*
9582c7da 1165 * Check our as-of timestamp against the element.
66325755 1166 */
eaeff70d 1167 if (flags & HAMMER_CURSOR_ASOF) {
fe7678ee 1168 if (hammer_btree_chkts(cursor->asof,
d113fda1
MD
1169 &node->elms[i].base) != 0) {
1170 continue;
1171 }
eaeff70d
MD
1172 /* success */
1173 } else {
9582c7da
MD
1174 if (r > 0) /* can only be +1 */
1175 continue;
eaeff70d 1176 /* success */
66325755 1177 }
d5530d22
MD
1178 cursor->index = i;
1179 error = 0;
eaeff70d 1180 if (hammer_debug_btree) {
47197d71
MD
1181 kprintf("RESULT-L %016llx[%d] (SUCCESS)\n",
1182 cursor->node->node_offset, i);
eaeff70d 1183 }
d5530d22
MD
1184 goto done;
1185 }
1186
1187 /*
eaeff70d 1188 * The search of the leaf node failed. i is the insertion point.
d5530d22 1189 */
d5530d22 1190failed:
b3deaf57 1191 if (hammer_debug_btree) {
47197d71
MD
1192 kprintf("RESULT-L %016llx[%d] (FAILED)\n",
1193 cursor->node->node_offset, i);
b3deaf57
MD
1194 }
1195
8cd0a023
MD
1196 /*
1197 * No exact match was found, i is now at the insertion point.
1198 *
1199 * If inserting split a full leaf before returning. This
1200 * may have the side effect of adjusting cursor->node and
1201 * cursor->index.
1202 */
1203 cursor->index = i;
eaeff70d 1204 if ((flags & HAMMER_CURSOR_INSERT) && enospc == 0 &&
47197d71 1205 btree_node_is_full(node)) {
8cd0a023 1206 error = btree_split_leaf(cursor);
d26d0ae9
MD
1207 if (error) {
1208 if (error != ENOSPC)
1209 goto done;
1210 enospc = 1;
d26d0ae9
MD
1211 }
1212 /*
1213 * reload stale pointers
1214 */
8cd0a023
MD
1215 /* NOT USED
1216 i = cursor->index;
1217 node = &cursor->node->internal;
1218 */
8cd0a023 1219 }
d26d0ae9
MD
1220
1221 /*
1222 * We reached a leaf but did not find the key we were looking for.
1223 * If this is an insert we will be properly positioned for an insert
1224 * (ENOENT) or spike (ENOSPC) operation.
1225 */
1226 error = enospc ? ENOSPC : ENOENT;
8cd0a023 1227done:
427e5fc6
MD
1228 return(error);
1229}
1230
8cd0a023 1231
427e5fc6 1232/************************************************************************
8cd0a023 1233 * SPLITTING AND MERGING *
427e5fc6
MD
1234 ************************************************************************
1235 *
1236 * These routines do all the dirty work required to split and merge nodes.
1237 */
1238
1239/*
8cd0a023 1240 * Split an internal node into two nodes and move the separator at the split
fe7678ee 1241 * point to the parent.
427e5fc6 1242 *
8cd0a023
MD
1243 * (cursor->node, cursor->index) indicates the element the caller intends
1244 * to push into. We will adjust node and index if that element winds
427e5fc6 1245 * up in the split node.
8cd0a023 1246 *
47197d71
MD
1247 * If we are at the root of the filesystem a new root must be created with
1248 * two elements, one pointing to the original root and one pointing to the
8cd0a023 1249 * newly allocated split node.
427e5fc6
MD
1250 */
1251static
1252int
8cd0a023 1253btree_split_internal(hammer_cursor_t cursor)
427e5fc6 1254{
8cd0a023
MD
1255 hammer_node_ondisk_t ondisk;
1256 hammer_node_t node;
1257 hammer_node_t parent;
1258 hammer_node_t new_node;
1259 hammer_btree_elm_t elm;
1260 hammer_btree_elm_t parent_elm;
b33e2cc0 1261 hammer_node_locklist_t locklist = NULL;
36f82b23 1262 hammer_mount_t hmp = cursor->trans->hmp;
427e5fc6
MD
1263 int parent_index;
1264 int made_root;
1265 int split;
1266 int error;
7f7c1f84 1267 int i;
8cd0a023 1268 const int esize = sizeof(*elm);
427e5fc6 1269
6a37e7e4
MD
1270 if ((error = hammer_cursor_upgrade(cursor)) != 0)
1271 return(error);
47197d71
MD
1272 error = hammer_btree_lock_children(cursor, &locklist);
1273 if (error)
1274 goto done;
6a37e7e4 1275
427e5fc6
MD
1276 /*
1277 * We are splitting but elms[split] will be promoted to the parent,
1278 * leaving the right hand node with one less element. If the
1279 * insertion point will be on the left-hand side adjust the split
1280 * point to give the right hand side one additional node.
1281 */
8cd0a023
MD
1282 node = cursor->node;
1283 ondisk = node->ondisk;
1284 split = (ondisk->count + 1) / 2;
427e5fc6
MD
1285 if (cursor->index <= split)
1286 --split;
427e5fc6
MD
1287
1288 /*
47197d71
MD
1289 * If we are at the root of the filesystem, create a new root node
1290 * with 1 element and split normally. Avoid making major
1291 * modifications until we know the whole operation will work.
427e5fc6 1292 */
8cd0a023 1293 if (ondisk->parent == 0) {
36f82b23 1294 parent = hammer_alloc_btree(cursor->trans, &error);
427e5fc6 1295 if (parent == NULL)
6a37e7e4 1296 goto done;
8cd0a023 1297 hammer_lock_ex(&parent->lock);
36f82b23 1298 hammer_modify_node_noundo(cursor->trans, parent);
8cd0a023
MD
1299 ondisk = parent->ondisk;
1300 ondisk->count = 1;
1301 ondisk->parent = 0;
1302 ondisk->type = HAMMER_BTREE_TYPE_INTERNAL;
47197d71 1303 ondisk->elms[0].base = hmp->root_btree_beg;
fe7678ee 1304 ondisk->elms[0].base.btype = node->ondisk->type;
8cd0a023 1305 ondisk->elms[0].internal.subtree_offset = node->node_offset;
47197d71 1306 ondisk->elms[1].base = hmp->root_btree_end;
10a5d1ba 1307 hammer_modify_node_done(parent);
fe7678ee 1308 /* ondisk->elms[1].base.btype - not used */
427e5fc6 1309 made_root = 1;
8cd0a023 1310 parent_index = 0; /* index of current node in parent */
427e5fc6
MD
1311 } else {
1312 made_root = 0;
8cd0a023
MD
1313 parent = cursor->parent;
1314 parent_index = cursor->parent_index;
427e5fc6 1315 }
427e5fc6
MD
1316
1317 /*
1318 * Split node into new_node at the split point.
1319 *
1320 * B O O O P N N B <-- P = node->elms[split]
1321 * 0 1 2 3 4 5 6 <-- subtree indices
1322 *
1323 * x x P x x
1324 * s S S s
1325 * / \
1326 * B O O O B B N N B <--- inner boundary points are 'P'
1327 * 0 1 2 3 4 5 6
1328 *
1329 */
36f82b23 1330 new_node = hammer_alloc_btree(cursor->trans, &error);
427e5fc6 1331 if (new_node == NULL) {
8cd0a023
MD
1332 if (made_root) {
1333 hammer_unlock(&parent->lock);
36f82b23 1334 hammer_delete_node(cursor->trans, parent);
8cd0a023
MD
1335 hammer_rel_node(parent);
1336 }
6a37e7e4 1337 goto done;
427e5fc6 1338 }
8cd0a023 1339 hammer_lock_ex(&new_node->lock);
427e5fc6
MD
1340
1341 /*
8cd0a023 1342 * Create the new node. P becomes the left-hand boundary in the
427e5fc6
MD
1343 * new node. Copy the right-hand boundary as well.
1344 *
1345 * elm is the new separator.
1346 */
36f82b23
MD
1347 hammer_modify_node_noundo(cursor->trans, new_node);
1348 hammer_modify_node_all(cursor->trans, node);
8cd0a023
MD
1349 ondisk = node->ondisk;
1350 elm = &ondisk->elms[split];
1351 bcopy(elm, &new_node->ondisk->elms[0],
1352 (ondisk->count - split + 1) * esize);
1353 new_node->ondisk->count = ondisk->count - split;
1354 new_node->ondisk->parent = parent->node_offset;
1355 new_node->ondisk->type = HAMMER_BTREE_TYPE_INTERNAL;
1356 KKASSERT(ondisk->type == new_node->ondisk->type);
427e5fc6
MD
1357
1358 /*
fe7678ee
MD
1359 * Cleanup the original node. Elm (P) becomes the new boundary,
1360 * its subtree_offset was moved to the new node. If we had created
427e5fc6
MD
1361 * a new root its parent pointer may have changed.
1362 */
8cd0a023 1363 elm->internal.subtree_offset = 0;
c0ade690 1364 ondisk->count = split;
427e5fc6
MD
1365
1366 /*
1367 * Insert the separator into the parent, fixup the parent's
1368 * reference to the original node, and reference the new node.
1369 * The separator is P.
1370 *
1371 * Remember that base.count does not include the right-hand boundary.
1372 */
36f82b23 1373 hammer_modify_node_all(cursor->trans, parent);
8cd0a023 1374 ondisk = parent->ondisk;
d26d0ae9 1375 KKASSERT(ondisk->count != HAMMER_BTREE_INT_ELMS);
8cd0a023 1376 parent_elm = &ondisk->elms[parent_index+1];
427e5fc6 1377 bcopy(parent_elm, parent_elm + 1,
8cd0a023
MD
1378 (ondisk->count - parent_index) * esize);
1379 parent_elm->internal.base = elm->base; /* separator P */
fe7678ee 1380 parent_elm->internal.base.btype = new_node->ondisk->type;
8cd0a023 1381 parent_elm->internal.subtree_offset = new_node->node_offset;
76376933 1382 ++ondisk->count;
10a5d1ba 1383 hammer_modify_node_done(parent);
427e5fc6 1384
7f7c1f84
MD
1385 /*
1386 * The children of new_node need their parent pointer set to new_node.
b33e2cc0
MD
1387 * The children have already been locked by
1388 * hammer_btree_lock_children().
7f7c1f84
MD
1389 */
1390 for (i = 0; i < new_node->ondisk->count; ++i) {
1391 elm = &new_node->ondisk->elms[i];
36f82b23 1392 error = btree_set_parent(cursor->trans, new_node, elm);
7f7c1f84
MD
1393 if (error) {
1394 panic("btree_split_internal: btree-fixup problem");
1395 }
1396 }
10a5d1ba 1397 hammer_modify_node_done(new_node);
7f7c1f84 1398
427e5fc6 1399 /*
47197d71 1400 * The filesystem's root B-Tree pointer may have to be updated.
427e5fc6
MD
1401 */
1402 if (made_root) {
47197d71
MD
1403 hammer_volume_t volume;
1404
1405 volume = hammer_get_root_volume(hmp, &error);
1406 KKASSERT(error == 0);
1407
e8599db1
MD
1408 hammer_modify_volume_field(cursor->trans, volume,
1409 vol0_btree_root);
47197d71 1410 volume->ondisk->vol0_btree_root = parent->node_offset;
10a5d1ba 1411 hammer_modify_volume_done(volume);
8cd0a023
MD
1412 node->ondisk->parent = parent->node_offset;
1413 if (cursor->parent) {
1414 hammer_unlock(&cursor->parent->lock);
1415 hammer_rel_node(cursor->parent);
1416 }
1417 cursor->parent = parent; /* lock'd and ref'd */
47197d71 1418 hammer_rel_volume(volume, 0);
427e5fc6 1419 }
10a5d1ba 1420 hammer_modify_node_done(node);
427e5fc6 1421
8cd0a023 1422
427e5fc6
MD
1423 /*
1424 * Ok, now adjust the cursor depending on which element the original
1425 * index was pointing at. If we are >= the split point the push node
1426 * is now in the new node.
1427 *
1428 * NOTE: If we are at the split point itself we cannot stay with the
1429 * original node because the push index will point at the right-hand
1430 * boundary, which is illegal.
8cd0a023
MD
1431 *
1432 * NOTE: The cursor's parent or parent_index must be adjusted for
1433 * the case where a new parent (new root) was created, and the case
1434 * where the cursor is now pointing at the split node.
427e5fc6
MD
1435 */
1436 if (cursor->index >= split) {
8cd0a023 1437 cursor->parent_index = parent_index + 1;
427e5fc6 1438 cursor->index -= split;
8cd0a023
MD
1439 hammer_unlock(&cursor->node->lock);
1440 hammer_rel_node(cursor->node);
1441 cursor->node = new_node; /* locked and ref'd */
1442 } else {
1443 cursor->parent_index = parent_index;
1444 hammer_unlock(&new_node->lock);
1445 hammer_rel_node(new_node);
427e5fc6 1446 }
76376933
MD
1447
1448 /*
1449 * Fixup left and right bounds
1450 */
1451 parent_elm = &parent->ondisk->elms[cursor->parent_index];
fbc6e32a
MD
1452 cursor->left_bound = &parent_elm[0].internal.base;
1453 cursor->right_bound = &parent_elm[1].internal.base;
b3deaf57
MD
1454 KKASSERT(hammer_btree_cmp(cursor->left_bound,
1455 &cursor->node->ondisk->elms[0].internal.base) <= 0);
1456 KKASSERT(hammer_btree_cmp(cursor->right_bound,
9944ae54 1457 &cursor->node->ondisk->elms[cursor->node->ondisk->count].internal.base) >= 0);
76376933 1458
6a37e7e4 1459done:
b33e2cc0 1460 hammer_btree_unlock_children(&locklist);
6a37e7e4
MD
1461 hammer_cursor_downgrade(cursor);
1462 return (error);
427e5fc6
MD
1463}
1464
1465/*
1466 * Same as the above, but splits a full leaf node.
6a37e7e4
MD
1467 *
1468 * This function
427e5fc6
MD
1469 */
1470static
1471int
8cd0a023 1472btree_split_leaf(hammer_cursor_t cursor)
427e5fc6 1473{
8cd0a023
MD
1474 hammer_node_ondisk_t ondisk;
1475 hammer_node_t parent;
1476 hammer_node_t leaf;
47197d71 1477 hammer_mount_t hmp;
8cd0a023
MD
1478 hammer_node_t new_leaf;
1479 hammer_btree_elm_t elm;
1480 hammer_btree_elm_t parent_elm;
b3deaf57 1481 hammer_base_elm_t mid_boundary;
427e5fc6
MD
1482 int parent_index;
1483 int made_root;
1484 int split;
1485 int error;
8cd0a023 1486 const size_t esize = sizeof(*elm);
427e5fc6 1487
6a37e7e4
MD
1488 if ((error = hammer_cursor_upgrade(cursor)) != 0)
1489 return(error);
1490
36f82b23
MD
1491 KKASSERT(hammer_btree_cmp(cursor->left_bound,
1492 &cursor->node->ondisk->elms[0].leaf.base) <= 0);
1493 KKASSERT(hammer_btree_cmp(cursor->right_bound,
1494 &cursor->node->ondisk->elms[cursor->node->ondisk->count-1].leaf.base) > 0);
1495
427e5fc6 1496 /*
8cd0a023
MD
1497 * Calculate the split point. If the insertion point will be on
1498 * the left-hand side adjust the split point to give the right
1499 * hand side one additional node.
fe7678ee
MD
1500 *
1501 * Spikes are made up of two leaf elements which cannot be
1502 * safely split.
427e5fc6 1503 */
8cd0a023
MD
1504 leaf = cursor->node;
1505 ondisk = leaf->ondisk;
1506 split = (ondisk->count + 1) / 2;
427e5fc6
MD
1507 if (cursor->index <= split)
1508 --split;
1509 error = 0;
40043e7f 1510 hmp = leaf->hmp;
427e5fc6 1511
fe7678ee 1512 elm = &ondisk->elms[split];
fe7678ee 1513
36f82b23
MD
1514 KKASSERT(hammer_btree_cmp(cursor->left_bound, &elm[-1].leaf.base) <= 0);
1515 KKASSERT(hammer_btree_cmp(cursor->left_bound, &elm->leaf.base) <= 0);
1516 KKASSERT(hammer_btree_cmp(cursor->right_bound, &elm->leaf.base) > 0);
1517 KKASSERT(hammer_btree_cmp(cursor->right_bound, &elm[1].leaf.base) > 0);
1518
427e5fc6
MD
1519 /*
1520 * If we are at the root of the tree, create a new root node with
1521 * 1 element and split normally. Avoid making major modifications
1522 * until we know the whole operation will work.
1523 */
8cd0a023 1524 if (ondisk->parent == 0) {
36f82b23 1525 parent = hammer_alloc_btree(cursor->trans, &error);
427e5fc6 1526 if (parent == NULL)
6a37e7e4 1527 goto done;
8cd0a023 1528 hammer_lock_ex(&parent->lock);
36f82b23 1529 hammer_modify_node_noundo(cursor->trans, parent);
8cd0a023
MD
1530 ondisk = parent->ondisk;
1531 ondisk->count = 1;
1532 ondisk->parent = 0;
1533 ondisk->type = HAMMER_BTREE_TYPE_INTERNAL;
47197d71 1534 ondisk->elms[0].base = hmp->root_btree_beg;
fe7678ee 1535 ondisk->elms[0].base.btype = leaf->ondisk->type;
8cd0a023 1536 ondisk->elms[0].internal.subtree_offset = leaf->node_offset;
47197d71 1537 ondisk->elms[1].base = hmp->root_btree_end;
fe7678ee 1538 /* ondisk->elms[1].base.btype = not used */
10a5d1ba 1539 hammer_modify_node_done(parent);
427e5fc6 1540 made_root = 1;
8cd0a023 1541 parent_index = 0; /* insertion point in parent */
427e5fc6
MD
1542 } else {
1543 made_root = 0;
8cd0a023
MD
1544 parent = cursor->parent;
1545 parent_index = cursor->parent_index;
427e5fc6 1546 }
427e5fc6
MD
1547
1548 /*
1549 * Split leaf into new_leaf at the split point. Select a separator
1550 * value in-between the two leafs but with a bent towards the right
1551 * leaf since comparisons use an 'elm >= separator' inequality.
1552 *
1553 * L L L L L L L L
1554 *
1555 * x x P x x
1556 * s S S s
1557 * / \
1558 * L L L L L L L L
1559 */
36f82b23 1560 new_leaf = hammer_alloc_btree(cursor->trans, &error);
427e5fc6 1561 if (new_leaf == NULL) {
8cd0a023
MD
1562 if (made_root) {
1563 hammer_unlock(&parent->lock);
36f82b23 1564 hammer_delete_node(cursor->trans, parent);
8cd0a023
MD
1565 hammer_rel_node(parent);
1566 }
6a37e7e4 1567 goto done;
427e5fc6 1568 }
8cd0a023 1569 hammer_lock_ex(&new_leaf->lock);
427e5fc6
MD
1570
1571 /*
36f82b23
MD
1572 * Create the new node and copy the leaf elements from the split
1573 * point on to the new node.
427e5fc6 1574 */
36f82b23
MD
1575 hammer_modify_node_all(cursor->trans, leaf);
1576 hammer_modify_node_noundo(cursor->trans, new_leaf);
8cd0a023
MD
1577 ondisk = leaf->ondisk;
1578 elm = &ondisk->elms[split];
1579 bcopy(elm, &new_leaf->ondisk->elms[0], (ondisk->count - split) * esize);
1580 new_leaf->ondisk->count = ondisk->count - split;
1581 new_leaf->ondisk->parent = parent->node_offset;
1582 new_leaf->ondisk->type = HAMMER_BTREE_TYPE_LEAF;
1583 KKASSERT(ondisk->type == new_leaf->ondisk->type);
10a5d1ba 1584 hammer_modify_node_done(new_leaf);
427e5fc6
MD
1585
1586 /*
8cd0a023
MD
1587 * Cleanup the original node. Because this is a leaf node and
1588 * leaf nodes do not have a right-hand boundary, there
c0ade690
MD
1589 * aren't any special edge cases to clean up. We just fixup the
1590 * count.
427e5fc6 1591 */
c0ade690 1592 ondisk->count = split;
427e5fc6
MD
1593
1594 /*
1595 * Insert the separator into the parent, fixup the parent's
1596 * reference to the original node, and reference the new node.
1597 * The separator is P.
1598 *
1599 * Remember that base.count does not include the right-hand boundary.
1600 * We are copying parent_index+1 to parent_index+2, not +0 to +1.
1601 */
36f82b23 1602 hammer_modify_node_all(cursor->trans, parent);
8cd0a023 1603 ondisk = parent->ondisk;
36f82b23 1604 KKASSERT(split != 0);
d26d0ae9 1605 KKASSERT(ondisk->count != HAMMER_BTREE_INT_ELMS);
8cd0a023 1606 parent_elm = &ondisk->elms[parent_index+1];
d26d0ae9
MD
1607 bcopy(parent_elm, parent_elm + 1,
1608 (ondisk->count - parent_index) * esize);
eaeff70d 1609
47197d71 1610 hammer_make_separator(&elm[-1].base, &elm[0].base, &parent_elm->base);
fe7678ee 1611 parent_elm->internal.base.btype = new_leaf->ondisk->type;
8cd0a023 1612 parent_elm->internal.subtree_offset = new_leaf->node_offset;
b3deaf57 1613 mid_boundary = &parent_elm->base;
76376933 1614 ++ondisk->count;
10a5d1ba 1615 hammer_modify_node_done(parent);
427e5fc6 1616
fe7678ee 1617 /*
47197d71 1618 * The filesystem's root B-Tree pointer may have to be updated.
427e5fc6
MD
1619 */
1620 if (made_root) {
47197d71
MD
1621 hammer_volume_t volume;
1622
1623 volume = hammer_get_root_volume(hmp, &error);
1624 KKASSERT(error == 0);
1625
e8599db1
MD
1626 hammer_modify_volume_field(cursor->trans, volume,
1627 vol0_btree_root);
47197d71 1628 volume->ondisk->vol0_btree_root = parent->node_offset;
10a5d1ba 1629 hammer_modify_volume_done(volume);
8cd0a023
MD
1630 leaf->ondisk->parent = parent->node_offset;
1631 if (cursor->parent) {
1632 hammer_unlock(&cursor->parent->lock);
1633 hammer_rel_node(cursor->parent);
1634 }
1635 cursor->parent = parent; /* lock'd and ref'd */
47197d71 1636 hammer_rel_volume(volume, 0);
427e5fc6 1637 }
10a5d1ba 1638 hammer_modify_node_done(leaf);
8cd0a023 1639
427e5fc6
MD
1640 /*
1641 * Ok, now adjust the cursor depending on which element the original
1642 * index was pointing at. If we are >= the split point the push node
1643 * is now in the new node.
1644 *
b3deaf57
MD
1645 * NOTE: If we are at the split point itself we need to select the
1646 * old or new node based on where key_beg's insertion point will be.
1647 * If we pick the wrong side the inserted element will wind up in
1648 * the wrong leaf node and outside that node's bounds.
427e5fc6 1649 */
b3deaf57
MD
1650 if (cursor->index > split ||
1651 (cursor->index == split &&
1652 hammer_btree_cmp(&cursor->key_beg, mid_boundary) >= 0)) {
8cd0a023 1653 cursor->parent_index = parent_index + 1;
427e5fc6 1654 cursor->index -= split;
8cd0a023
MD
1655 hammer_unlock(&cursor->node->lock);
1656 hammer_rel_node(cursor->node);
1657 cursor->node = new_leaf;
1658 } else {
1659 cursor->parent_index = parent_index;
1660 hammer_unlock(&new_leaf->lock);
1661 hammer_rel_node(new_leaf);
427e5fc6 1662 }
76376933
MD
1663
1664 /*
1665 * Fixup left and right bounds
1666 */
1667 parent_elm = &parent->ondisk->elms[cursor->parent_index];
fbc6e32a
MD
1668 cursor->left_bound = &parent_elm[0].internal.base;
1669 cursor->right_bound = &parent_elm[1].internal.base;
eaeff70d
MD
1670
1671 /*
47197d71 1672 * Assert that the bounds are correct.
eaeff70d 1673 */
b3deaf57
MD
1674 KKASSERT(hammer_btree_cmp(cursor->left_bound,
1675 &cursor->node->ondisk->elms[0].leaf.base) <= 0);
1676 KKASSERT(hammer_btree_cmp(cursor->right_bound,
47197d71 1677 &cursor->node->ondisk->elms[cursor->node->ondisk->count-1].leaf.base) > 0);
36f82b23
MD
1678 KKASSERT(hammer_btree_cmp(cursor->left_bound, &cursor->key_beg) <= 0);
1679 KKASSERT(hammer_btree_cmp(cursor->right_bound, &cursor->key_beg) > 0);
76376933 1680
6a37e7e4
MD
1681done:
1682 hammer_cursor_downgrade(cursor);
1683 return (error);
427e5fc6
MD
1684}
1685
32c90105
MD
1686/*
1687 * Recursively correct the right-hand boundary's create_tid to (tid) as
1688 * long as the rest of the key matches. We have to recurse upward in
1689 * the tree as well as down the left side of each parent's right node.
1690 *
1691 * Return EDEADLK if we were only partially successful, forcing the caller
1692 * to try again. The original cursor is not modified. This routine can
1693 * also fail with EDEADLK if it is forced to throw away a portion of its
1694 * record history.
1695 *
1696 * The caller must pass a downgraded cursor to us (otherwise we can't dup it).
1697 */
1698struct hammer_rhb {
1699 TAILQ_ENTRY(hammer_rhb) entry;
1700 hammer_node_t node;
1701 int index;
1702};
1703
1704TAILQ_HEAD(hammer_rhb_list, hammer_rhb);
1705
1706int
1707hammer_btree_correct_rhb(hammer_cursor_t cursor, hammer_tid_t tid)
1708{
1709 struct hammer_rhb_list rhb_list;
1710 hammer_base_elm_t elm;
1711 hammer_node_t orig_node;
1712 struct hammer_rhb *rhb;
1713 int orig_index;
1714 int error;
1715
1716 TAILQ_INIT(&rhb_list);
1717
1718 /*
1719 * Save our position so we can restore it on return. This also
1720 * gives us a stable 'elm'.
1721 */
1722 orig_node = cursor->node;
1723 hammer_ref_node(orig_node);
1724 hammer_lock_sh(&orig_node->lock);
1725 orig_index = cursor->index;
1726 elm = &orig_node->ondisk->elms[orig_index].base;
1727
1728 /*
1729 * Now build a list of parents going up, allocating a rhb
1730 * structure for each one.
1731 */
1732 while (cursor->parent) {
1733 /*
1734 * Stop if we no longer have any right-bounds to fix up
1735 */
1736 if (elm->obj_id != cursor->right_bound->obj_id ||
1737 elm->rec_type != cursor->right_bound->rec_type ||
1738 elm->key != cursor->right_bound->key) {
1739 break;
1740 }
1741
1742 /*
1743 * Stop if the right-hand bound's create_tid does not
47197d71 1744 * need to be corrected.
32c90105
MD
1745 */
1746 if (cursor->right_bound->create_tid >= tid)
1747 break;
1748
32c90105
MD
1749 rhb = kmalloc(sizeof(*rhb), M_HAMMER, M_WAITOK|M_ZERO);
1750 rhb->node = cursor->parent;
1751 rhb->index = cursor->parent_index;
1752 hammer_ref_node(rhb->node);
1753 hammer_lock_sh(&rhb->node->lock);
1754 TAILQ_INSERT_HEAD(&rhb_list, rhb, entry);
1755
1756 hammer_cursor_up(cursor);
1757 }
1758
1759 /*
1760 * now safely adjust the right hand bound for each rhb. This may
1761 * also require taking the right side of the tree and iterating down
1762 * ITS left side.
1763 */
1764 error = 0;
1765 while (error == 0 && (rhb = TAILQ_FIRST(&rhb_list)) != NULL) {
1766 error = hammer_cursor_seek(cursor, rhb->node, rhb->index);
32c90105
MD
1767 if (error)
1768 break;
1769 TAILQ_REMOVE(&rhb_list, rhb, entry);
1770 hammer_unlock(&rhb->node->lock);
1771 hammer_rel_node(rhb->node);
1772 kfree(rhb, M_HAMMER);
1773
1774 switch (cursor->node->ondisk->type) {
1775 case HAMMER_BTREE_TYPE_INTERNAL:
1776 /*
1777 * Right-boundary for parent at internal node
1778 * is one element to the right of the element whos
1779 * right boundary needs adjusting. We must then
1780 * traverse down the left side correcting any left
1781 * bounds (which may now be too far to the left).
1782 */
1783 ++cursor->index;
1784 error = hammer_btree_correct_lhb(cursor, tid);
1785 break;
32c90105
MD
1786 default:
1787 panic("hammer_btree_correct_rhb(): Bad node type");
1788 error = EINVAL;
1789 break;
1790 }
1791 }
1792
1793 /*
1794 * Cleanup
1795 */
1796 while ((rhb = TAILQ_FIRST(&rhb_list)) != NULL) {
1797 TAILQ_REMOVE(&rhb_list, rhb, entry);
1798 hammer_unlock(&rhb->node->lock);
1799 hammer_rel_node(rhb->node);
1800 kfree(rhb, M_HAMMER);
1801 }
1802 error = hammer_cursor_seek(cursor, orig_node, orig_index);
1803 hammer_unlock(&orig_node->lock);
1804 hammer_rel_node(orig_node);
1805 return (error);
1806}
1807
1808/*
1809 * Similar to rhb (in fact, rhb calls lhb), but corrects the left hand
1810 * bound going downward starting at the current cursor position.
1811 *
1812 * This function does not restore the cursor after use.
1813 */
1814int
1815hammer_btree_correct_lhb(hammer_cursor_t cursor, hammer_tid_t tid)
1816{
1817 struct hammer_rhb_list rhb_list;
1818 hammer_base_elm_t elm;
1819 hammer_base_elm_t cmp;
1820 struct hammer_rhb *rhb;
1821 int error;
1822
1823 TAILQ_INIT(&rhb_list);
1824
1825 cmp = &cursor->node->ondisk->elms[cursor->index].base;
1826
1827 /*
1828 * Record the node and traverse down the left-hand side for all
1829 * matching records needing a boundary correction.
1830 */
1831 error = 0;
1832 for (;;) {
1833 rhb = kmalloc(sizeof(*rhb), M_HAMMER, M_WAITOK|M_ZERO);
1834 rhb->node = cursor->node;
1835 rhb->index = cursor->index;
1836 hammer_ref_node(rhb->node);
1837 hammer_lock_sh(&rhb->node->lock);
1838 TAILQ_INSERT_HEAD(&rhb_list, rhb, entry);
1839
1840 if (cursor->node->ondisk->type == HAMMER_BTREE_TYPE_INTERNAL) {
1841 /*
1842 * Nothing to traverse down if we are at the right
1843 * boundary of an internal node.
1844 */
1845 if (cursor->index == cursor->node->ondisk->count)
1846 break;
1847 } else {
1848 elm = &cursor->node->ondisk->elms[cursor->index].base;
1849 if (elm->btype == HAMMER_BTREE_TYPE_RECORD)
1850 break;
47197d71 1851 panic("Illegal leaf record type %02x", elm->btype);
32c90105
MD
1852 }
1853 error = hammer_cursor_down(cursor);
1854 if (error)
1855 break;
1856
1857 elm = &cursor->node->ondisk->elms[cursor->index].base;
1858 if (elm->obj_id != cmp->obj_id ||
1859 elm->rec_type != cmp->rec_type ||
1860 elm->key != cmp->key) {
1861 break;
1862 }
1863 if (elm->create_tid >= tid)
1864 break;
1865
1866 }
1867
1868 /*
1869 * Now we can safely adjust the left-hand boundary from the bottom-up.
1870 * The last element we remove from the list is the caller's right hand
1871 * boundary, which must also be adjusted.
1872 */
1873 while (error == 0 && (rhb = TAILQ_FIRST(&rhb_list)) != NULL) {
1874 error = hammer_cursor_seek(cursor, rhb->node, rhb->index);
1875 if (error)
1876 break;
1877 TAILQ_REMOVE(&rhb_list, rhb, entry);
1878 hammer_unlock(&rhb->node->lock);
1879 hammer_rel_node(rhb->node);
1880 kfree(rhb, M_HAMMER);
1881
1882 elm = &cursor->node->ondisk->elms[cursor->index].base;
1883 if (cursor->node->ondisk->type == HAMMER_BTREE_TYPE_INTERNAL) {
36f82b23 1884 hammer_modify_node(cursor->trans, cursor->node,
19619882
MD
1885 &elm->create_tid,
1886 sizeof(elm->create_tid));
32c90105 1887 elm->create_tid = tid;
10a5d1ba 1888 hammer_modify_node_done(cursor->node);
32c90105
MD
1889 } else {
1890 panic("hammer_btree_correct_lhb(): Bad element type");
1891 }
1892 }
1893
1894 /*
1895 * Cleanup
1896 */
1897 while ((rhb = TAILQ_FIRST(&rhb_list)) != NULL) {
1898 TAILQ_REMOVE(&rhb_list, rhb, entry);
1899 hammer_unlock(&rhb->node->lock);
1900 hammer_rel_node(rhb->node);
1901 kfree(rhb, M_HAMMER);
1902 }
1903 return (error);
1904}
1905
427e5fc6 1906/*
f36a9737
MD
1907 * Attempt to remove the locked, empty or want-to-be-empty B-Tree node at
1908 * (cursor->node). Returns 0 on success, EDEADLK if we could not complete
1909 * the operation due to a deadlock, or some other error.
8cd0a023 1910 *
f36a9737
MD
1911 * This routine is always called with an empty, locked leaf but may recurse
1912 * into want-to-be-empty parents as part of its operation.
b3deaf57 1913 *
f36a9737
MD
1914 * On return the cursor may end up pointing to an internal node, suitable
1915 * for further iteration but not for an immediate insertion or deletion.
8cd0a023 1916 */
f36a9737 1917static int
46fe7ae1 1918btree_remove(hammer_cursor_t cursor)
8cd0a023
MD
1919{
1920 hammer_node_ondisk_t ondisk;
195c19a1 1921 hammer_btree_elm_t elm;
195c19a1 1922 hammer_node_t node;
8cd0a023 1923 hammer_node_t parent;
fe7678ee 1924 const int esize = sizeof(*elm);
8cd0a023 1925 int error;
8cd0a023 1926
fe7678ee
MD
1927 node = cursor->node;
1928
47197d71
MD
1929 /*
1930 * When deleting the root of the filesystem convert it to
1931 * an empty leaf node. Internal nodes cannot be empty.
1932 */
fe7678ee 1933 if (node->ondisk->parent == 0) {
f36a9737 1934 KKASSERT(cursor->parent == NULL);
36f82b23 1935 hammer_modify_node_all(cursor->trans, node);
fe7678ee 1936 ondisk = node->ondisk;
195c19a1
MD
1937 ondisk->type = HAMMER_BTREE_TYPE_LEAF;
1938 ondisk->count = 0;
10a5d1ba 1939 hammer_modify_node_done(node);
b3deaf57 1940 cursor->index = 0;
47197d71 1941 return(0);
8cd0a023
MD
1942 }
1943
1944 /*
f36a9737
MD
1945 * Attempt to remove the parent's reference to the child. If the
1946 * parent would become empty we have to recurse. If we fail we
1947 * leave the parent pointing to an empty leaf node.
8cd0a023 1948 */
fe7678ee 1949 parent = cursor->parent;
fe7678ee 1950
f36a9737
MD
1951 if (parent->ondisk->count == 1) {
1952 /*
1953 * This special cursor_up_locked() call leaves the original
1954 * node exclusively locked and referenced, leaves the
1955 * original parent locked (as the new node), and locks the
1956 * new parent. It can return EDEADLK.
1957 */
1958 error = hammer_cursor_up_locked(cursor);
1959 if (error == 0) {
1960 error = btree_remove(cursor);
1961 if (error == 0) {
1962 hammer_modify_node_all(cursor->trans, node);
1963 ondisk = node->ondisk;
1964 ondisk->type = HAMMER_BTREE_TYPE_DELETED;
1965 ondisk->count = 0;
1966 hammer_modify_node_done(node);
1967 hammer_flush_node(node);
1968 hammer_delete_node(cursor->trans, node);
1969 } else {
1970 kprintf("Warning: BTREE_REMOVE: Defering "
1971 "parent removal1 @ %016llx, skipping\n",
1972 node->node_offset);
1973 }
1974 hammer_unlock(&node->lock);
1975 hammer_rel_node(node);
1976 } else {
1977 kprintf("Warning: BTREE_REMOVE: Defering parent "
1978 "removal2 @ %016llx, skipping\n",
1979 node->node_offset);
1980 }
1981 } else {
1982 KKASSERT(parent->ondisk->count > 1);
6a37e7e4 1983
f36a9737
MD
1984 /*
1985 * Delete the subtree reference in the parent
1986 */
1987 hammer_modify_node_all(cursor->trans, parent);
1988 ondisk = parent->ondisk;
1989 KKASSERT(ondisk->type == HAMMER_BTREE_TYPE_INTERNAL);
1990 elm = &ondisk->elms[cursor->parent_index];
1991 KKASSERT(elm->internal.subtree_offset == node->node_offset);
1992 KKASSERT(ondisk->count > 0);
1993 bcopy(&elm[1], &elm[0],
1994 (ondisk->count - cursor->parent_index) * esize);
1995 --ondisk->count;
10a5d1ba 1996 hammer_modify_node_done(parent);
f36a9737
MD
1997 hammer_flush_node(node);
1998 hammer_delete_node(cursor->trans, node);
6a37e7e4 1999
f36a9737
MD
2000 /*
2001 * cursor->node is invalid, cursor up to make the cursor
2002 * valid again.
2003 */
2004 error = hammer_cursor_up(cursor);
6a37e7e4 2005 }
f36a9737 2006 return (error);
6a37e7e4
MD
2007}
2008
7f7c1f84 2009/*
fe7678ee
MD
2010 * The element (elm) has been moved to a new internal node (node).
2011 *
2012 * If the element represents a pointer to an internal node that node's
2013 * parent must be adjusted to the element's new location.
2014 *
6a37e7e4 2015 * XXX deadlock potential here with our exclusive locks
7f7c1f84 2016 */
7f7c1f84 2017int
36f82b23
MD
2018btree_set_parent(hammer_transaction_t trans, hammer_node_t node,
2019 hammer_btree_elm_t elm)
7f7c1f84 2020{
7f7c1f84
MD
2021 hammer_node_t child;
2022 int error;
2023
2024 error = 0;
2025
fe7678ee 2026 switch(elm->base.btype) {
7f7c1f84 2027 case HAMMER_BTREE_TYPE_INTERNAL:
fe7678ee 2028 case HAMMER_BTREE_TYPE_LEAF:
19619882
MD
2029 child = hammer_get_node(node->hmp, elm->internal.subtree_offset,
2030 0, &error);
7f7c1f84 2031 if (error == 0) {
c9b9e29d 2032 hammer_modify_node_field(trans, child, parent);
7f7c1f84 2033 child->ondisk->parent = node->node_offset;
10a5d1ba 2034 hammer_modify_node_done(child);
7f7c1f84
MD
2035 hammer_rel_node(child);
2036 }
2037 break;
7f7c1f84 2038 default:
fe7678ee 2039 break;
7f7c1f84
MD
2040 }
2041 return(error);
2042}
2043
b33e2cc0
MD
2044/*
2045 * Exclusively lock all the children of node. This is used by the split
2046 * code to prevent anyone from accessing the children of a cursor node
2047 * while we fix-up its parent offset.
2048 *
2049 * If we don't lock the children we can really mess up cursors which block
2050 * trying to cursor-up into our node.
2051 *
b33e2cc0
MD
2052 * On failure EDEADLK (or some other error) is returned. If a deadlock
2053 * error is returned the cursor is adjusted to block on termination.
2054 */
2055int
2056hammer_btree_lock_children(hammer_cursor_t cursor,
2057 struct hammer_node_locklist **locklistp)
2058{
2059 hammer_node_t node;
2060 hammer_node_locklist_t item;
2061 hammer_node_ondisk_t ondisk;
2062 hammer_btree_elm_t elm;
b33e2cc0
MD
2063 hammer_node_t child;
2064 int error;
2065 int i;
2066
2067 node = cursor->node;
2068 ondisk = node->ondisk;
2069 error = 0;
2070 for (i = 0; error == 0 && i < ondisk->count; ++i) {
2071 elm = &ondisk->elms[i];
2072
b33e2cc0
MD
2073 switch(elm->base.btype) {
2074 case HAMMER_BTREE_TYPE_INTERNAL:
2075 case HAMMER_BTREE_TYPE_LEAF:
f36a9737 2076 KKASSERT(elm->internal.subtree_offset != 0);
40043e7f 2077 child = hammer_get_node(node->hmp,
b33e2cc0 2078 elm->internal.subtree_offset,
19619882 2079 0, &error);
b33e2cc0 2080 break;
b33e2cc0 2081 default:
47197d71 2082 child = NULL;
b33e2cc0
MD
2083 break;
2084 }
2085 if (child) {
2086 if (hammer_lock_ex_try(&child->lock) != 0) {
2087 if (cursor->deadlk_node == NULL) {
1ff9f58e 2088 cursor->deadlk_node = child;
b33e2cc0
MD
2089 hammer_ref_node(cursor->deadlk_node);
2090 }
2091 error = EDEADLK;
a84a197d 2092 hammer_rel_node(child);
b33e2cc0
MD
2093 } else {
2094 item = kmalloc(sizeof(*item),
2095 M_HAMMER, M_WAITOK);
2096 item->next = *locklistp;
2097 item->node = child;
2098 *locklistp = item;
2099 }
2100 }
2101 }
2102 if (error)
2103 hammer_btree_unlock_children(locklistp);
2104 return(error);
2105}
2106
2107
2108/*
2109 * Release previously obtained node locks.
2110 */
2f85fa4d 2111void
b33e2cc0
MD
2112hammer_btree_unlock_children(struct hammer_node_locklist **locklistp)
2113{
2114 hammer_node_locklist_t item;
2115
2116 while ((item = *locklistp) != NULL) {
2117 *locklistp = item->next;
2118 hammer_unlock(&item->node->lock);
2119 hammer_rel_node(item->node);
2120 kfree(item, M_HAMMER);
2121 }
2122}
2123
8cd0a023
MD
2124/************************************************************************
2125 * MISCELLANIOUS SUPPORT *
2126 ************************************************************************/
2127
2128/*
d26d0ae9 2129 * Compare two B-Tree elements, return -N, 0, or +N (e.g. similar to strcmp).
8cd0a023 2130 *
d113fda1 2131 * Note that for this particular function a return value of -1, 0, or +1
9582c7da 2132 * can denote a match if create_tid is otherwise discounted. A create_tid
d5530d22 2133 * of zero is considered to be 'infinity' in comparisons.
d113fda1 2134 *
8cd0a023 2135 * See also hammer_rec_rb_compare() and hammer_rec_cmp() in hammer_object.c.
8cd0a023
MD
2136 */
2137int
2138hammer_btree_cmp(hammer_base_elm_t key1, hammer_base_elm_t key2)
2139{
2f85fa4d
MD
2140 if (key1->localization < key2->localization)
2141 return(-5);
2142 if (key1->localization > key2->localization)
2143 return(5);
2144
d26d0ae9
MD
2145 if (key1->obj_id < key2->obj_id)
2146 return(-4);
2147 if (key1->obj_id > key2->obj_id)
2148 return(4);
8cd0a023 2149
d26d0ae9
MD
2150 if (key1->rec_type < key2->rec_type)
2151 return(-3);
2152 if (key1->rec_type > key2->rec_type)
2153 return(3);
8cd0a023 2154
8cd0a023
MD
2155 if (key1->key < key2->key)
2156 return(-2);
2157 if (key1->key > key2->key)
2158 return(2);
d113fda1 2159
d5530d22 2160 /*
9582c7da
MD
2161 * A create_tid of zero indicates a record which is undeletable
2162 * and must be considered to have a value of positive infinity.
d5530d22 2163 */
9582c7da
MD
2164 if (key1->create_tid == 0) {
2165 if (key2->create_tid == 0)
d5530d22
MD
2166 return(0);
2167 return(1);
2168 }
9582c7da 2169 if (key2->create_tid == 0)
d5530d22 2170 return(-1);
9582c7da 2171 if (key1->create_tid < key2->create_tid)
d113fda1 2172 return(-1);
9582c7da 2173 if (key1->create_tid > key2->create_tid)
d113fda1 2174 return(1);
8cd0a023
MD
2175 return(0);
2176}
2177
c0ade690 2178/*
d5530d22
MD
2179 * Test a timestamp against an element to determine whether the
2180 * element is visible. A timestamp of 0 means 'infinity'.
c0ade690
MD
2181 */
2182int
d5530d22 2183hammer_btree_chkts(hammer_tid_t asof, hammer_base_elm_t base)
c0ade690 2184{
d5530d22
MD
2185 if (asof == 0) {
2186 if (base->delete_tid)
2187 return(1);
2188 return(0);
2189 }
2190 if (asof < base->create_tid)
d26d0ae9 2191 return(-1);
d5530d22 2192 if (base->delete_tid && asof >= base->delete_tid)
d26d0ae9 2193 return(1);
c0ade690
MD
2194 return(0);
2195}
2196
8cd0a023
MD
2197/*
2198 * Create a separator half way inbetween key1 and key2. For fields just
d5530d22
MD
2199 * one unit apart, the separator will match key2. key1 is on the left-hand
2200 * side and key2 is on the right-hand side.
8cd0a023 2201 *
9391cded 2202 * key2 must be >= the separator. It is ok for the separator to match key2.
36f82b23 2203 *
9391cded
MD
2204 * NOTE: Even if key1 does not match key2, the separator may wind up matching
2205 * key2.
2206 *
2207 * NOTE: It might be beneficial to just scrap this whole mess and just
2208 * set the separator to key2.
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2209 */
2210#define MAKE_SEPARATOR(key1, key2, dest, field) \
2211 dest->field = key1->field + ((key2->field - key1->field + 1) >> 1);
2212
2213static void
2214hammer_make_separator(hammer_base_elm_t key1, hammer_base_elm_t key2,
2215 hammer_base_elm_t dest)
2216{
2217 bzero(dest, sizeof(*dest));
d5530d22 2218
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2219 dest->rec_type = key2->rec_type;
2220 dest->key = key2->key;
2f85fa4d 2221 dest->obj_id = key2->obj_id;
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2222 dest->create_tid = key2->create_tid;
2223
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2224 MAKE_SEPARATOR(key1, key2, dest, localization);
2225 if (key1->localization == key2->localization) {
2226 MAKE_SEPARATOR(key1, key2, dest, obj_id);
2227 if (key1->obj_id == key2->obj_id) {
2228 MAKE_SEPARATOR(key1, key2, dest, rec_type);
2229 if (key1->rec_type == key2->rec_type) {
2230 MAKE_SEPARATOR(key1, key2, dest, key);
2231 /*
2232 * Don't bother creating a separator for
2233 * create_tid, which also conveniently avoids
2234 * having to handle the create_tid == 0
2235 * (infinity) case. Just leave create_tid
2236 * set to key2.
2237 *
2238 * Worst case, dest matches key2 exactly,
2239 * which is acceptable.
2240 */
2241 }
d5530d22 2242 }
d113fda1 2243 }
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2244}
2245
2246#undef MAKE_SEPARATOR
2247
2248/*
2249 * Return whether a generic internal or leaf node is full
2250 */
2251static int
2252btree_node_is_full(hammer_node_ondisk_t node)
2253{
2254 switch(node->type) {
2255 case HAMMER_BTREE_TYPE_INTERNAL:
2256 if (node->count == HAMMER_BTREE_INT_ELMS)
2257 return(1);
2258 break;
2259 case HAMMER_BTREE_TYPE_LEAF:
2260 if (node->count == HAMMER_BTREE_LEAF_ELMS)
2261 return(1);
2262 break;
2263 default:
2264 panic("illegal btree subtype");
2265 }
2266 return(0);
2267}
9944ae54 2268
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2269#if 0
2270static int
2271btree_max_elements(u_int8_t type)
2272{
2273 if (type == HAMMER_BTREE_TYPE_LEAF)
2274 return(HAMMER_BTREE_LEAF_ELMS);
2275 if (type == HAMMER_BTREE_TYPE_INTERNAL)
2276 return(HAMMER_BTREE_INT_ELMS);
2277 panic("btree_max_elements: bad type %d\n", type);
2278}
2279#endif
2280
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2281void
2282hammer_print_btree_node(hammer_node_ondisk_t ondisk)
2283{
2284 hammer_btree_elm_t elm;
2285 int i;
2286
47197d71 2287 kprintf("node %p count=%d parent=%016llx type=%c\n",
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2288 ondisk, ondisk->count, ondisk->parent, ondisk->type);
2289
2290 /*
2291 * Dump both boundary elements if an internal node
2292 */
2293 if (ondisk->type == HAMMER_BTREE_TYPE_INTERNAL) {
2294 for (i = 0; i <= ondisk->count; ++i) {
2295 elm = &ondisk->elms[i];
2296 hammer_print_btree_elm(elm, ondisk->type, i);
2297 }
2298 } else {
2299 for (i = 0; i < ondisk->count; ++i) {
2300 elm = &ondisk->elms[i];
2301 hammer_print_btree_elm(elm, ondisk->type, i);
2302 }
2303 }
2304}
2305
2306void
2307hammer_print_btree_elm(hammer_btree_elm_t elm, u_int8_t type, int i)
2308{
2309 kprintf(" %2d", i);
7dc57964 2310 kprintf("\tobj_id = %016llx\n", elm->base.obj_id);
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2311 kprintf("\tkey = %016llx\n", elm->base.key);
2312 kprintf("\tcreate_tid = %016llx\n", elm->base.create_tid);
2313 kprintf("\tdelete_tid = %016llx\n", elm->base.delete_tid);
2314 kprintf("\trec_type = %04x\n", elm->base.rec_type);
2315 kprintf("\tobj_type = %02x\n", elm->base.obj_type);
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2316 kprintf("\tbtype = %02x (%c)\n",
2317 elm->base.btype,
2318 (elm->base.btype ? elm->base.btype : '?'));
2f85fa4d 2319 kprintf("\tlocalization = %02x\n", elm->base.localization);
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2320
2321 switch(type) {
2322 case HAMMER_BTREE_TYPE_INTERNAL:
47197d71 2323 kprintf("\tsubtree_off = %016llx\n",
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2324 elm->internal.subtree_offset);
2325 break;
fe7678ee 2326 case HAMMER_BTREE_TYPE_RECORD:
11ad5ade 2327 kprintf("\tatime = %016llx\n", elm->leaf.atime);
47197d71 2328 kprintf("\tdata_offset = %016llx\n", elm->leaf.data_offset);
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2329 kprintf("\tdata_len = %08x\n", elm->leaf.data_len);
2330 kprintf("\tdata_crc = %08x\n", elm->leaf.data_crc);
fe7678ee 2331 break;
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2332 }
2333}