1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 * 25 * Copyright 2015 Nexenta Systems, Inc. All rights reserved. 26 */ 27 28 #include "libuutil_common.h" 29 30 #include <stdlib.h> 31 #include <string.h> 32 #include <unistd.h> 33 #include <sys/avl.h> 34 35 static uu_avl_pool_t uu_null_apool = { &uu_null_apool, &uu_null_apool }; 36 static pthread_mutex_t uu_apool_list_lock = PTHREAD_MUTEX_INITIALIZER; 37 38 /* 39 * The index mark change on every insert and delete, to catch stale 40 * references. 41 * 42 * We leave the low bit alone, since the avl code uses it. 43 */ 44 #define INDEX_MAX (sizeof (uintptr_t) - 2) 45 #define INDEX_NEXT(m) (((m) == INDEX_MAX)? 2 : ((m) + 2) & INDEX_MAX) 46 47 #define INDEX_DECODE(i) ((i) & ~INDEX_MAX) 48 #define INDEX_ENCODE(p, n) (((n) & ~INDEX_MAX) | (p)->ua_index) 49 #define INDEX_VALID(p, i) (((i) & INDEX_MAX) == (p)->ua_index) 50 #define INDEX_CHECK(i) (((i) & INDEX_MAX) != 0) 51 52 /* 53 * When an element is inactive (not in a tree), we keep a marked pointer to 54 * its containing pool in its first word, and a NULL pointer in its second. 55 * 56 * On insert, we use these to verify that it comes from the correct pool. 57 */ 58 #define NODE_ARRAY(p, n) ((uintptr_t *)((uintptr_t)(n) + \ 59 (pp)->uap_nodeoffset)) 60 61 #define POOL_TO_MARKER(pp) (((uintptr_t)(pp) | 1)) 62 63 #define DEAD_MARKER 0xc4 64 65 uu_avl_pool_t * 66 uu_avl_pool_create(const char *name, size_t objsize, size_t nodeoffset, 67 uu_compare_fn_t *compare_func, uint32_t flags) 68 { 69 uu_avl_pool_t *pp, *next, *prev; 70 71 if (name == NULL || 72 uu_check_name(name, UU_NAME_DOMAIN) == -1 || 73 nodeoffset + sizeof (uu_avl_node_t) > objsize || 74 compare_func == NULL) { 75 uu_set_error(UU_ERROR_INVALID_ARGUMENT); 76 return (NULL); 77 } 78 79 if (flags & ~UU_AVL_POOL_DEBUG) { 80 uu_set_error(UU_ERROR_UNKNOWN_FLAG); 81 return (NULL); 82 } 83 84 pp = uu_zalloc(sizeof (uu_avl_pool_t)); 85 if (pp == NULL) { 86 uu_set_error(UU_ERROR_NO_MEMORY); 87 return (NULL); 88 } 89 90 (void) strlcpy(pp->uap_name, name, sizeof (pp->uap_name)); 91 pp->uap_nodeoffset = nodeoffset; 92 pp->uap_objsize = objsize; 93 pp->uap_cmp = compare_func; 94 if (flags & UU_AVL_POOL_DEBUG) 95 pp->uap_debug = 1; 96 pp->uap_last_index = 0; 97 98 (void) pthread_mutex_init(&pp->uap_lock, NULL); 99 100 pp->uap_null_avl.ua_next_enc = UU_PTR_ENCODE(&pp->uap_null_avl); 101 pp->uap_null_avl.ua_prev_enc = UU_PTR_ENCODE(&pp->uap_null_avl); 102 103 (void) pthread_mutex_lock(&uu_apool_list_lock); 104 pp->uap_next = next = &uu_null_apool; 105 pp->uap_prev = prev = next->uap_prev; 106 next->uap_prev = pp; 107 prev->uap_next = pp; 108 (void) pthread_mutex_unlock(&uu_apool_list_lock); 109 110 return (pp); 111 } 112 113 void 114 uu_avl_pool_destroy(uu_avl_pool_t *pp) 115 { 116 if (pp->uap_debug) { 117 if (pp->uap_null_avl.ua_next_enc != 118 UU_PTR_ENCODE(&pp->uap_null_avl) || 119 pp->uap_null_avl.ua_prev_enc != 120 UU_PTR_ENCODE(&pp->uap_null_avl)) { 121 uu_panic("uu_avl_pool_destroy: Pool \"%.*s\" (%p) has " 122 "outstanding avls, or is corrupt.\n", 123 (int)sizeof (pp->uap_name), pp->uap_name, 124 (void *)pp); 125 } 126 } 127 (void) pthread_mutex_lock(&uu_apool_list_lock); 128 pp->uap_next->uap_prev = pp->uap_prev; 129 pp->uap_prev->uap_next = pp->uap_next; 130 (void) pthread_mutex_unlock(&uu_apool_list_lock); 131 pp->uap_prev = NULL; 132 pp->uap_next = NULL; 133 uu_free(pp); 134 } 135 136 void 137 uu_avl_node_init(void *base, uu_avl_node_t *np, uu_avl_pool_t *pp) 138 { 139 uintptr_t *na = (uintptr_t *)np; 140 141 if (pp->uap_debug) { 142 uintptr_t offset = (uintptr_t)np - (uintptr_t)base; 143 if (offset + sizeof (*np) > pp->uap_objsize) { 144 uu_panic("uu_avl_node_init(%p, %p, %p (\"%s\")): " 145 "offset %ld doesn't fit in object (size %ld)\n", 146 base, (void *)np, (void *)pp, pp->uap_name, 147 (long)offset, (long)pp->uap_objsize); 148 } 149 if (offset != pp->uap_nodeoffset) { 150 uu_panic("uu_avl_node_init(%p, %p, %p (\"%s\")): " 151 "offset %ld doesn't match pool's offset (%ld)\n", 152 base, (void *)np, (void *)pp, pp->uap_name, 153 (long)offset, (long)pp->uap_objsize); 154 } 155 } 156 157 na[0] = POOL_TO_MARKER(pp); 158 na[1] = 0; 159 } 160 161 void 162 uu_avl_node_fini(void *base, uu_avl_node_t *np, uu_avl_pool_t *pp) 163 { 164 uintptr_t *na = (uintptr_t *)np; 165 166 if (pp->uap_debug) { 167 if (na[0] == DEAD_MARKER && na[1] == DEAD_MARKER) { 168 uu_panic("uu_avl_node_fini(%p, %p, %p (\"%s\")): " 169 "node already finied\n", 170 base, (void *)np, (void *)pp, pp->uap_name); 171 } 172 if (na[0] != POOL_TO_MARKER(pp) || na[1] != 0) { 173 uu_panic("uu_avl_node_fini(%p, %p, %p (\"%s\")): " 174 "node corrupt, in tree, or in different pool\n", 175 base, (void *)np, (void *)pp, pp->uap_name); 176 } 177 } 178 179 na[0] = DEAD_MARKER; 180 na[1] = DEAD_MARKER; 181 na[2] = DEAD_MARKER; 182 } 183 184 struct uu_avl_node_compare_info { 185 uu_compare_fn_t *ac_compare; 186 void *ac_private; 187 void *ac_right; 188 void *ac_found; 189 }; 190 191 static int 192 uu_avl_node_compare(const void *l, const void *r) 193 { 194 struct uu_avl_node_compare_info *info = 195 (struct uu_avl_node_compare_info *)l; 196 197 int res = info->ac_compare(r, info->ac_right, info->ac_private); 198 199 if (res == 0) { 200 if (info->ac_found == NULL) 201 info->ac_found = (void *)r; 202 return (-1); 203 } 204 if (res < 0) 205 return (1); 206 return (-1); 207 } 208 209 uu_avl_t * 210 uu_avl_create(uu_avl_pool_t *pp, void *parent, uint32_t flags) 211 { 212 uu_avl_t *ap, *next, *prev; 213 214 if (flags & ~UU_AVL_DEBUG) { 215 uu_set_error(UU_ERROR_UNKNOWN_FLAG); 216 return (NULL); 217 } 218 219 ap = uu_zalloc(sizeof (*ap)); 220 if (ap == NULL) { 221 uu_set_error(UU_ERROR_NO_MEMORY); 222 return (NULL); 223 } 224 225 ap->ua_pool = pp; 226 ap->ua_parent_enc = UU_PTR_ENCODE(parent); 227 ap->ua_debug = pp->uap_debug || (flags & UU_AVL_DEBUG); 228 ap->ua_index = (pp->uap_last_index = INDEX_NEXT(pp->uap_last_index)); 229 230 avl_create(&ap->ua_tree, &uu_avl_node_compare, pp->uap_objsize, 231 pp->uap_nodeoffset); 232 233 ap->ua_null_walk.uaw_next = &ap->ua_null_walk; 234 ap->ua_null_walk.uaw_prev = &ap->ua_null_walk; 235 236 (void) pthread_mutex_lock(&pp->uap_lock); 237 next = &pp->uap_null_avl; 238 prev = UU_PTR_DECODE(next->ua_prev_enc); 239 ap->ua_next_enc = UU_PTR_ENCODE(next); 240 ap->ua_prev_enc = UU_PTR_ENCODE(prev); 241 next->ua_prev_enc = UU_PTR_ENCODE(ap); 242 prev->ua_next_enc = UU_PTR_ENCODE(ap); 243 (void) pthread_mutex_unlock(&pp->uap_lock); 244 245 return (ap); 246 } 247 248 void 249 uu_avl_destroy(uu_avl_t *ap) 250 { 251 uu_avl_pool_t *pp = ap->ua_pool; 252 253 if (ap->ua_debug) { 254 if (avl_numnodes(&ap->ua_tree) != 0) { 255 uu_panic("uu_avl_destroy(%p): tree not empty\n", 256 (void *)ap); 257 } 258 if (ap->ua_null_walk.uaw_next != &ap->ua_null_walk || 259 ap->ua_null_walk.uaw_prev != &ap->ua_null_walk) { 260 uu_panic("uu_avl_destroy(%p): outstanding walkers\n", 261 (void *)ap); 262 } 263 } 264 (void) pthread_mutex_lock(&pp->uap_lock); 265 UU_AVL_PTR(ap->ua_next_enc)->ua_prev_enc = ap->ua_prev_enc; 266 UU_AVL_PTR(ap->ua_prev_enc)->ua_next_enc = ap->ua_next_enc; 267 (void) pthread_mutex_unlock(&pp->uap_lock); 268 ap->ua_prev_enc = UU_PTR_ENCODE(NULL); 269 ap->ua_next_enc = UU_PTR_ENCODE(NULL); 270 271 ap->ua_pool = NULL; 272 avl_destroy(&ap->ua_tree); 273 274 uu_free(ap); 275 } 276 277 void 278 uu_avl_recreate(uu_avl_t *ap) 279 { 280 uu_avl_pool_t *pp = ap->ua_pool; 281 282 avl_destroy(&ap->ua_tree); 283 avl_create(&ap->ua_tree, &uu_avl_node_compare, pp->uap_objsize, 284 pp->uap_nodeoffset); 285 } 286 287 size_t 288 uu_avl_numnodes(uu_avl_t *ap) 289 { 290 return (avl_numnodes(&ap->ua_tree)); 291 } 292 293 void * 294 uu_avl_first(uu_avl_t *ap) 295 { 296 return (avl_first(&ap->ua_tree)); 297 } 298 299 void * 300 uu_avl_last(uu_avl_t *ap) 301 { 302 return (avl_last(&ap->ua_tree)); 303 } 304 305 void * 306 uu_avl_next(uu_avl_t *ap, void *node) 307 { 308 return (AVL_NEXT(&ap->ua_tree, node)); 309 } 310 311 void * 312 uu_avl_prev(uu_avl_t *ap, void *node) 313 { 314 return (AVL_PREV(&ap->ua_tree, node)); 315 } 316 317 static void 318 _avl_walk_init(uu_avl_walk_t *wp, uu_avl_t *ap, uint32_t flags) 319 { 320 uu_avl_walk_t *next, *prev; 321 322 int robust = (flags & UU_WALK_ROBUST); 323 int direction = (flags & UU_WALK_REVERSE)? -1 : 1; 324 325 (void) memset(wp, 0, sizeof (*wp)); 326 wp->uaw_avl = ap; 327 wp->uaw_robust = robust; 328 wp->uaw_dir = direction; 329 330 if (direction > 0) 331 wp->uaw_next_result = avl_first(&ap->ua_tree); 332 else 333 wp->uaw_next_result = avl_last(&ap->ua_tree); 334 335 if (ap->ua_debug || robust) { 336 wp->uaw_next = next = &ap->ua_null_walk; 337 wp->uaw_prev = prev = next->uaw_prev; 338 next->uaw_prev = wp; 339 prev->uaw_next = wp; 340 } 341 } 342 343 static void * 344 _avl_walk_advance(uu_avl_walk_t *wp, uu_avl_t *ap) 345 { 346 void *np = wp->uaw_next_result; 347 348 avl_tree_t *t = &ap->ua_tree; 349 350 if (np == NULL) 351 return (NULL); 352 353 wp->uaw_next_result = (wp->uaw_dir > 0)? AVL_NEXT(t, np) : 354 AVL_PREV(t, np); 355 356 return (np); 357 } 358 359 static void 360 _avl_walk_fini(uu_avl_walk_t *wp) 361 { 362 if (wp->uaw_next != NULL) { 363 wp->uaw_next->uaw_prev = wp->uaw_prev; 364 wp->uaw_prev->uaw_next = wp->uaw_next; 365 wp->uaw_next = NULL; 366 wp->uaw_prev = NULL; 367 } 368 wp->uaw_avl = NULL; 369 wp->uaw_next_result = NULL; 370 } 371 372 uu_avl_walk_t * 373 uu_avl_walk_start(uu_avl_t *ap, uint32_t flags) 374 { 375 uu_avl_walk_t *wp; 376 377 if (flags & ~(UU_WALK_ROBUST | UU_WALK_REVERSE)) { 378 uu_set_error(UU_ERROR_UNKNOWN_FLAG); 379 return (NULL); 380 } 381 382 wp = uu_zalloc(sizeof (*wp)); 383 if (wp == NULL) { 384 uu_set_error(UU_ERROR_NO_MEMORY); 385 return (NULL); 386 } 387 388 _avl_walk_init(wp, ap, flags); 389 return (wp); 390 } 391 392 void * 393 uu_avl_walk_next(uu_avl_walk_t *wp) 394 { 395 return (_avl_walk_advance(wp, wp->uaw_avl)); 396 } 397 398 void 399 uu_avl_walk_end(uu_avl_walk_t *wp) 400 { 401 _avl_walk_fini(wp); 402 uu_free(wp); 403 } 404 405 int 406 uu_avl_walk(uu_avl_t *ap, uu_walk_fn_t *func, void *private, uint32_t flags) 407 { 408 void *e; 409 uu_avl_walk_t my_walk; 410 411 int status = UU_WALK_NEXT; 412 413 if (flags & ~(UU_WALK_ROBUST | UU_WALK_REVERSE)) { 414 uu_set_error(UU_ERROR_UNKNOWN_FLAG); 415 return (-1); 416 } 417 418 _avl_walk_init(&my_walk, ap, flags); 419 while (status == UU_WALK_NEXT && 420 (e = _avl_walk_advance(&my_walk, ap)) != NULL) 421 status = (*func)(e, private); 422 _avl_walk_fini(&my_walk); 423 424 if (status >= 0) 425 return (0); 426 uu_set_error(UU_ERROR_CALLBACK_FAILED); 427 return (-1); 428 } 429 430 void 431 uu_avl_remove(uu_avl_t *ap, void *elem) 432 { 433 uu_avl_walk_t *wp; 434 uu_avl_pool_t *pp = ap->ua_pool; 435 uintptr_t *na = NODE_ARRAY(pp, elem); 436 437 if (ap->ua_debug) { 438 /* 439 * invalidate outstanding uu_avl_index_ts. 440 */ 441 ap->ua_index = INDEX_NEXT(ap->ua_index); 442 } 443 444 /* 445 * Robust walkers most be advanced, if we are removing the node 446 * they are currently using. In debug mode, non-robust walkers 447 * are also on the walker list. 448 */ 449 for (wp = ap->ua_null_walk.uaw_next; wp != &ap->ua_null_walk; 450 wp = wp->uaw_next) { 451 if (wp->uaw_robust) { 452 if (elem == wp->uaw_next_result) 453 (void) _avl_walk_advance(wp, ap); 454 } else if (wp->uaw_next_result != NULL) { 455 uu_panic("uu_avl_remove(%p, %p): active non-robust " 456 "walker\n", (void *)ap, elem); 457 } 458 } 459 460 avl_remove(&ap->ua_tree, elem); 461 462 na[0] = POOL_TO_MARKER(pp); 463 na[1] = 0; 464 } 465 466 void * 467 uu_avl_teardown(uu_avl_t *ap, void **cookie) 468 { 469 void *elem = avl_destroy_nodes(&ap->ua_tree, cookie); 470 471 if (elem != NULL) { 472 uu_avl_pool_t *pp = ap->ua_pool; 473 uintptr_t *na = NODE_ARRAY(pp, elem); 474 475 na[0] = POOL_TO_MARKER(pp); 476 na[1] = 0; 477 } 478 return (elem); 479 } 480 481 void * 482 uu_avl_find(uu_avl_t *ap, void *elem, void *private, uu_avl_index_t *out) 483 { 484 struct uu_avl_node_compare_info info; 485 void *result; 486 487 info.ac_compare = ap->ua_pool->uap_cmp; 488 info.ac_private = private; 489 info.ac_right = elem; 490 info.ac_found = NULL; 491 492 result = avl_find(&ap->ua_tree, &info, out); 493 if (out != NULL) 494 *out = INDEX_ENCODE(ap, *out); 495 496 if (ap->ua_debug && result != NULL) 497 uu_panic("uu_avl_find: internal error: avl_find succeeded\n"); 498 499 return (info.ac_found); 500 } 501 502 void 503 uu_avl_insert(uu_avl_t *ap, void *elem, uu_avl_index_t idx) 504 { 505 if (ap->ua_debug) { 506 uu_avl_pool_t *pp = ap->ua_pool; 507 uintptr_t *na = NODE_ARRAY(pp, elem); 508 509 if (na[1] != 0) 510 uu_panic("uu_avl_insert(%p, %p, %p): node already " 511 "in tree, or corrupt\n", 512 (void *)ap, elem, (void *)idx); 513 if (na[0] == 0) 514 uu_panic("uu_avl_insert(%p, %p, %p): node not " 515 "initialized\n", 516 (void *)ap, elem, (void *)idx); 517 if (na[0] != POOL_TO_MARKER(pp)) 518 uu_panic("uu_avl_insert(%p, %p, %p): node from " 519 "other pool, or corrupt\n", 520 (void *)ap, elem, (void *)idx); 521 522 if (!INDEX_VALID(ap, idx)) 523 uu_panic("uu_avl_insert(%p, %p, %p): %s\n", 524 (void *)ap, elem, (void *)idx, 525 INDEX_CHECK(idx)? "outdated index" : 526 "invalid index"); 527 528 /* 529 * invalidate outstanding uu_avl_index_ts. 530 */ 531 ap->ua_index = INDEX_NEXT(ap->ua_index); 532 } 533 avl_insert(&ap->ua_tree, elem, INDEX_DECODE(idx)); 534 } 535 536 void * 537 uu_avl_nearest_next(uu_avl_t *ap, uu_avl_index_t idx) 538 { 539 if (ap->ua_debug && !INDEX_VALID(ap, idx)) 540 uu_panic("uu_avl_nearest_next(%p, %p): %s\n", 541 (void *)ap, (void *)idx, INDEX_CHECK(idx)? 542 "outdated index" : "invalid index"); 543 return (avl_nearest(&ap->ua_tree, INDEX_DECODE(idx), AVL_AFTER)); 544 } 545 546 void * 547 uu_avl_nearest_prev(uu_avl_t *ap, uu_avl_index_t idx) 548 { 549 if (ap->ua_debug && !INDEX_VALID(ap, idx)) 550 uu_panic("uu_avl_nearest_prev(%p, %p): %s\n", 551 (void *)ap, (void *)idx, INDEX_CHECK(idx)? 552 "outdated index" : "invalid index"); 553 return (avl_nearest(&ap->ua_tree, INDEX_DECODE(idx), AVL_BEFORE)); 554 } 555 556 /* 557 * called from uu_lockup() and uu_release(), as part of our fork1()-safety. 558 */ 559 void 560 uu_avl_lockup(void) 561 { 562 uu_avl_pool_t *pp; 563 564 (void) pthread_mutex_lock(&uu_apool_list_lock); 565 for (pp = uu_null_apool.uap_next; pp != &uu_null_apool; 566 pp = pp->uap_next) 567 (void) pthread_mutex_lock(&pp->uap_lock); 568 } 569 570 void 571 uu_avl_release(void) 572 { 573 uu_avl_pool_t *pp; 574 575 for (pp = uu_null_apool.uap_next; pp != &uu_null_apool; 576 pp = pp->uap_next) 577 (void) pthread_mutex_unlock(&pp->uap_lock); 578 (void) pthread_mutex_unlock(&uu_apool_list_lock); 579 }