vm_radix.c revision 247742
1174294Sobrien/* 2131702Smbr * Copyright (c) 2013 EMC Corp. 3174294Sobrien * Copyright (c) 2011 Jeffrey Roberson <jeff@freebsd.org> 4174294Sobrien * Copyright (c) 2008 Mayur Shardul <mayur.shardul@gmail.com> 5174294Sobrien * All rights reserved. 6131702Smbr * 7174294Sobrien * Redistribution and use in source and binary forms, with or without 8131702Smbr * modification, are permitted provided that the following conditions 9174294Sobrien * are met: 10174294Sobrien * 1. Redistributions of source code must retain the above copyright 11131702Smbr * notice, this list of conditions and the following disclaimer. 12174294Sobrien * 2. Redistributions in binary form must reproduce the above copyright 13174294Sobrien * notice, this list of conditions and the following disclaimer in the 14131702Smbr * documentation and/or other materials provided with the distribution. 15174294Sobrien * 16174294Sobrien * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17131702Smbr * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18174294Sobrien * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19131702Smbr * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20174294Sobrien * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21174294Sobrien * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22174294Sobrien * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23131702Smbr * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24174294Sobrien * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25131702Smbr * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26174294Sobrien * SUCH DAMAGE. 27174294Sobrien * 28174294Sobrien */ 29174294Sobrien 30174294Sobrien/* 31174294Sobrien * Path-compressed radix trie implementation. 32174294Sobrien * The following code is not generalized into a general purpose library 33174294Sobrien * because there are way too many parameters embedded that should really 34174294Sobrien * be decided by the library consumers. At the same time, consumers 35174294Sobrien * of this code must achieve highest possible performance. 36174294Sobrien * 37174294Sobrien * The implementation takes into account the following rationale: 38174294Sobrien * - Size of the nodes might be as small as possible. 39174294Sobrien * - There is no bias toward lookup operations over inserts or removes, 40174294Sobrien * and vice-versa. 41174294Sobrien * - In average there are not many complete levels, than level 42174294Sobrien * compression may just complicate things. 43174294Sobrien */ 44174294Sobrien 45174294Sobrien#include <sys/cdefs.h> 46174294Sobrien 47174294Sobrien#include "opt_ddb.h" 48174294Sobrien 49174294Sobrien#include <sys/param.h> 50174294Sobrien#include <sys/systm.h> 51174294Sobrien#include <sys/kernel.h> 52174294Sobrien#include <sys/vmmeter.h> 53174294Sobrien 54174294Sobrien#include <vm/uma.h> 55174294Sobrien#include <vm/vm.h> 56174294Sobrien#include <vm/vm_param.h> 57174294Sobrien#include <vm/vm_page.h> 58174294Sobrien#include <vm/vm_radix.h> 59174294Sobrien 60174294Sobrien#ifdef DDB 61174294Sobrien#include <ddb/ddb.h> 62174294Sobrien#endif 63174294Sobrien 64174294Sobrien/* 65174294Sobrien * Such sizes should permit to keep node children contained into a single 66174294Sobrien * cache-line, or to at least not span many of those. 67174294Sobrien * In particular, sparse tries should however be compressed properly and 68174294Sobrien * then make some extra-levels not a big deal. 69174294Sobrien */ 70174294Sobrien#ifdef __LP64__ 71174294Sobrien#define VM_RADIX_WIDTH 4 72174294Sobrien#else 73174294Sobrien#define VM_RADIX_WIDTH 3 74174294Sobrien#endif 75174294Sobrien 76174294Sobrien#define VM_RADIX_COUNT (1 << VM_RADIX_WIDTH) 77174294Sobrien#define VM_RADIX_MASK (VM_RADIX_COUNT - 1) 78174294Sobrien#define VM_RADIX_LIMIT \ 79174294Sobrien (howmany((sizeof(vm_pindex_t) * NBBY), VM_RADIX_WIDTH) - 1) 80174294Sobrien 81174294Sobrien/* Flag bits stored in node pointers. */ 82174294Sobrien#define VM_RADIX_ISLEAF 0x1 83174294Sobrien#define VM_RADIX_FLAGS 0x1 84174294Sobrien#define VM_RADIX_PAD VM_RADIX_FLAGS 85174294Sobrien 86174294Sobrien/* Returns one unit associated with specified level. */ 87174294Sobrien#define VM_RADIX_UNITLEVEL(lev) \ 88174294Sobrien ((vm_pindex_t)1 << ((VM_RADIX_LIMIT - (lev)) * VM_RADIX_WIDTH)) 89174294Sobrien 90174294Sobrienstruct vm_radix_node { 91174294Sobrien void *rn_child[VM_RADIX_COUNT]; /* Child nodes. */ 92174294Sobrien vm_pindex_t rn_owner; /* Owner of record. */ 93174294Sobrien uint16_t rn_count; /* Valid children. */ 94174294Sobrien uint16_t rn_clev; /* Current level. */ 95174294Sobrien}; 96174294Sobrien 97174294Sobrienstatic uma_zone_t vm_radix_node_zone; 98174294Sobrien 99174294Sobrien/* 100174294Sobrien * Allocate a radix node. Pre-allocation ensures that the request will be 101174294Sobrien * always successfully satisfied. 102174294Sobrien */ 103174294Sobrienstatic __inline struct vm_radix_node * 104174294Sobrienvm_radix_node_get(vm_pindex_t owner, uint16_t count, uint16_t clevel) 105174294Sobrien{ 106174294Sobrien struct vm_radix_node *rnode; 107174294Sobrien 108174294Sobrien rnode = uma_zalloc(vm_radix_node_zone, M_NOWAIT | M_ZERO); 109174294Sobrien 110174294Sobrien /* 111174294Sobrien * The required number of nodes might be already correctly 112174294Sobrien * pre-allocated in vm_radix_init(). However, UMA can reserve 113174294Sobrien * few nodes on per-cpu specific buckets, which will not be 114174294Sobrien * accessible from the curcpu. The allocation could then 115174294Sobrien * return NULL when the pre-allocation pool is close to be 116174294Sobrien * exhausted. Anyway, in practice this should never be a 117174294Sobrien * problem because a new node is not always required for 118174294Sobrien * insert, thus the pre-allocation pool should already have 119174294Sobrien * some extra-pages that indirectly deal with this situation. 120174294Sobrien */ 121174294Sobrien if (rnode == NULL) 122174294Sobrien panic("%s: uma_zalloc() returned NULL for a new node", 123174294Sobrien __func__); 124174294Sobrien rnode->rn_owner = owner; 125174294Sobrien rnode->rn_count = count; 126174294Sobrien rnode->rn_clev = clevel; 127174294Sobrien return (rnode); 128174294Sobrien} 129174294Sobrien 130174294Sobrien/* 131174294Sobrien * Free radix node. 132174294Sobrien */ 133174294Sobrienstatic __inline void 134174294Sobrienvm_radix_node_put(struct vm_radix_node *rnode) 135174294Sobrien{ 136174294Sobrien 137174294Sobrien uma_zfree(vm_radix_node_zone, rnode); 138174294Sobrien} 139174294Sobrien 140174294Sobrien/* 141174294Sobrien * Return the position in the array for a given level. 142174294Sobrien */ 143174294Sobrienstatic __inline int 144174294Sobrienvm_radix_slot(vm_pindex_t index, uint16_t level) 145174294Sobrien{ 146174294Sobrien 147174294Sobrien return ((index >> ((VM_RADIX_LIMIT - level) * VM_RADIX_WIDTH)) & 148174294Sobrien VM_RADIX_MASK); 149174294Sobrien} 150174294Sobrien 151174294Sobrien/* Trims the key after the specified level. */ 152174294Sobrienstatic __inline vm_pindex_t 153174294Sobrienvm_radix_trimkey(vm_pindex_t index, uint16_t level) 154174294Sobrien{ 155174294Sobrien vm_pindex_t ret; 156174294Sobrien 157174294Sobrien ret = index; 158174294Sobrien if (level < VM_RADIX_LIMIT) { 159174294Sobrien ret >>= (VM_RADIX_LIMIT - level) * VM_RADIX_WIDTH; 160174294Sobrien ret <<= (VM_RADIX_LIMIT - level) * VM_RADIX_WIDTH; 161174294Sobrien } 162174294Sobrien return (ret); 163174294Sobrien} 164174294Sobrien 165174294Sobrien/* 166174294Sobrien * Get the root node for a radix tree. 167174294Sobrien */ 168174294Sobrienstatic __inline struct vm_radix_node * 169174294Sobrienvm_radix_getroot(struct vm_radix *rtree) 170174294Sobrien{ 171174294Sobrien 172174294Sobrien return ((struct vm_radix_node *)(rtree->rt_root & ~VM_RADIX_FLAGS)); 173174294Sobrien} 174174294Sobrien 175174294Sobrien/* 176174294Sobrien * Set the root node for a radix tree. 177174294Sobrien */ 178174294Sobrienstatic __inline void 179174294Sobrienvm_radix_setroot(struct vm_radix *rtree, struct vm_radix_node *rnode) 180174294Sobrien{ 181174294Sobrien 182174294Sobrien rtree->rt_root = (uintptr_t)rnode; 183174294Sobrien} 184174294Sobrien 185174294Sobrien/* 186174294Sobrien * Returns the associated page extracted from rnode if available, 187174294Sobrien * NULL otherwise. 188174294Sobrien */ 189174294Sobrienstatic __inline vm_page_t 190174294Sobrienvm_radix_node_page(struct vm_radix_node *rnode) 191174294Sobrien{ 192174294Sobrien 193174294Sobrien return ((((uintptr_t)rnode & VM_RADIX_ISLEAF) != 0) ? 194174294Sobrien (vm_page_t)((uintptr_t)rnode & ~VM_RADIX_FLAGS) : NULL); 195174294Sobrien} 196174294Sobrien 197174294Sobrien/* 198174294Sobrien * Adds the page as a child of provided node. 199174294Sobrien */ 200174294Sobrienstatic __inline void 201174294Sobrienvm_radix_addpage(struct vm_radix_node *rnode, vm_pindex_t index, uint16_t clev, 202174294Sobrien vm_page_t page) 203174294Sobrien{ 204174294Sobrien int slot; 205174294Sobrien 206174294Sobrien slot = vm_radix_slot(index, clev); 207174294Sobrien rnode->rn_child[slot] = (void *)((uintptr_t)page | VM_RADIX_ISLEAF); 208174294Sobrien} 209174294Sobrien 210174294Sobrien/* 211174294Sobrien * Returns the slot where two keys differ. 212174294Sobrien * It cannot accept 2 equal keys. 213174294Sobrien */ 214174294Sobrienstatic __inline uint16_t 215174294Sobrienvm_radix_keydiff(vm_pindex_t index1, vm_pindex_t index2) 216174294Sobrien{ 217174294Sobrien uint16_t clev; 218174294Sobrien 219174294Sobrien KASSERT(index1 != index2, ("%s: passing the same key value %jx", 220174294Sobrien __func__, (uintmax_t)index1)); 221174294Sobrien 222174294Sobrien index1 ^= index2; 223174294Sobrien for (clev = 0; clev <= VM_RADIX_LIMIT ; clev++) 224174294Sobrien if (vm_radix_slot(index1, clev)) 225174294Sobrien return (clev); 226174294Sobrien panic("%s: it might have not reached this point", __func__); 227174294Sobrien return (0); 228174294Sobrien} 229174294Sobrien 230174294Sobrien/* 231174294Sobrien * Returns TRUE if it can be determined that key does not belong to the 232174294Sobrien * specified rnode. FALSE otherwise. 233174294Sobrien */ 234174294Sobrienstatic __inline boolean_t 235174294Sobrienvm_radix_keybarr(struct vm_radix_node *rnode, vm_pindex_t idx) 236174294Sobrien{ 237174294Sobrien 238174294Sobrien if (rnode->rn_clev > 0) { 239174294Sobrien idx = vm_radix_trimkey(idx, rnode->rn_clev - 1); 240174294Sobrien idx -= rnode->rn_owner; 241174294Sobrien if (idx != 0) 242174294Sobrien return (TRUE); 243174294Sobrien } 244174294Sobrien return (FALSE); 245174294Sobrien} 246174294Sobrien 247174294Sobrien/* 248174294Sobrien * Adjusts the idx key to the first upper level available, based on a valid 249174294Sobrien * initial level and map of available levels. 250174294Sobrien * Returns a value bigger than 0 to signal that there are not valid levels 251174294Sobrien * available. 252174294Sobrien */ 253174294Sobrienstatic __inline int 254174294Sobrienvm_radix_addlev(vm_pindex_t *idx, boolean_t *levels, uint16_t ilev) 255174294Sobrien{ 256174294Sobrien vm_pindex_t wrapidx; 257174294Sobrien 258174294Sobrien for (; levels[ilev] == FALSE || 259174294Sobrien vm_radix_slot(*idx, ilev) == (VM_RADIX_COUNT - 1); ilev--) 260174294Sobrien if (ilev == 0) 261174294Sobrien break; 262174294Sobrien KASSERT(ilev > 0 || levels[0] == TRUE, 263174294Sobrien ("%s: levels back-scanning problem", __func__)); 264174294Sobrien if (ilev == 0 && vm_radix_slot(*idx, ilev) == (VM_RADIX_COUNT - 1)) 265174294Sobrien return (1); 266174294Sobrien wrapidx = *idx; 267174294Sobrien *idx = vm_radix_trimkey(*idx, ilev); 268174294Sobrien *idx += VM_RADIX_UNITLEVEL(ilev); 269174294Sobrien return (*idx < wrapidx); 270174294Sobrien} 271174294Sobrien 272174294Sobrien/* 273174294Sobrien * Adjusts the idx key to the first lower level available, based on a valid 274174294Sobrien * initial level and map of available levels. 275174294Sobrien * Returns a value bigger than 0 to signal that there are not valid levels 276174294Sobrien * available. 277174294Sobrien */ 278174294Sobrienstatic __inline int 279174294Sobrienvm_radix_declev(vm_pindex_t *idx, boolean_t *levels, uint16_t ilev) 280174294Sobrien{ 281174294Sobrien vm_pindex_t wrapidx; 282174294Sobrien 283174294Sobrien for (; levels[ilev] == FALSE || 284174294Sobrien vm_radix_slot(*idx, ilev) == 0; ilev--) 285174294Sobrien if (ilev == 0) 286174294Sobrien break; 287174294Sobrien KASSERT(ilev > 0 || levels[0] == TRUE, 288174294Sobrien ("%s: levels back-scanning problem", __func__)); 289174294Sobrien if (ilev == 0 && vm_radix_slot(*idx, ilev) == 0) 290174294Sobrien return (1); 291174294Sobrien wrapidx = *idx; 292174294Sobrien *idx = vm_radix_trimkey(*idx, ilev); 293174294Sobrien *idx |= VM_RADIX_UNITLEVEL(ilev) - 1; 294174294Sobrien *idx -= VM_RADIX_UNITLEVEL(ilev); 295174294Sobrien return (*idx > wrapidx); 296174294Sobrien} 297174294Sobrien 298174294Sobrien/* 299174294Sobrien * Internal handwork for vm_radix_reclaim_allonodes() primitive. 300174294Sobrien * This function is recrusive. 301174294Sobrien */ 302174294Sobrienstatic void 303174294Sobrienvm_radix_reclaim_allnodes_int(struct vm_radix_node *rnode) 304174294Sobrien{ 305174294Sobrien int slot; 306174294Sobrien 307174294Sobrien for (slot = 0; slot < VM_RADIX_COUNT && rnode->rn_count != 0; slot++) { 308174294Sobrien if (rnode->rn_child[slot] == NULL) 309174294Sobrien continue; 310174294Sobrien if (vm_radix_node_page(rnode->rn_child[slot]) == NULL) 311174294Sobrien vm_radix_reclaim_allnodes_int(rnode->rn_child[slot]); 312174294Sobrien rnode->rn_count--; 313174294Sobrien } 314174294Sobrien vm_radix_node_put(rnode); 315174294Sobrien} 316174294Sobrien 317174294Sobrien#ifdef INVARIANTS 318174294Sobrien/* 319174294Sobrien * Radix node zone destructor. 320174294Sobrien */ 321174294Sobrienstatic void 322174294Sobrienvm_radix_node_zone_dtor(void *mem, int size __unused, void *arg __unused) 323174294Sobrien{ 324174294Sobrien struct vm_radix_node *rnode; 325174294Sobrien 326174294Sobrien rnode = mem; 327174294Sobrien KASSERT(rnode->rn_count == 0, 328174294Sobrien ("vm_radix_node_put: Freeing node %p with %d children\n", mem, 329174294Sobrien rnode->rn_count)); 330174294Sobrien} 331174294Sobrien#endif 332174294Sobrien 333174294Sobrien/* 334174294Sobrien * Pre-allocate intermediate nodes from the UMA slab zone. 335174294Sobrien */ 336174294Sobrienstatic void 337174294Sobrienvm_radix_prealloc(void *arg __unused) 338174294Sobrien{ 339174294Sobrien 340174294Sobrien if (!uma_zone_reserve_kva(vm_radix_node_zone, cnt.v_page_count)) 341174294Sobrien panic("%s: unable to create new zone", __func__); 342174294Sobrien uma_prealloc(vm_radix_node_zone, cnt.v_page_count); 343174294Sobrien} 344174294SobrienSYSINIT(vm_radix_prealloc, SI_SUB_KMEM, SI_ORDER_SECOND, vm_radix_prealloc, 345174294Sobrien NULL); 346174294Sobrien 347174294Sobrien/* 348174294Sobrien * Initialize the UMA slab zone. 349174294Sobrien * Until vm_radix_prealloc() is called, the zone will be served by the 350174294Sobrien * UMA boot-time pre-allocated pool of pages. 351174294Sobrien */ 352174294Sobrienvoid 353174294Sobrienvm_radix_init(void) 354174294Sobrien{ 355174294Sobrien 356174294Sobrien vm_radix_node_zone = uma_zcreate("RADIX NODE", 357174294Sobrien sizeof(struct vm_radix_node), NULL, 358174294Sobrien#ifdef INVARIANTS 359174294Sobrien vm_radix_node_zone_dtor, 360174294Sobrien#else 361174294Sobrien NULL, 362174294Sobrien#endif 363174294Sobrien NULL, NULL, VM_RADIX_PAD, UMA_ZONE_VM | UMA_ZONE_NOFREE); 364174294Sobrien} 365174294Sobrien 366174294Sobrien/* 367174294Sobrien * Inserts the key-value pair in to the trie. 368174294Sobrien * Panics if the key already exists. 369174294Sobrien */ 370174294Sobrienvoid 371174294Sobrienvm_radix_insert(struct vm_radix *rtree, vm_pindex_t index, vm_page_t page) 372174294Sobrien{ 373174294Sobrien vm_pindex_t newind; 374174294Sobrien struct vm_radix_node *rnode, *tmp, *tmp2; 375174294Sobrien vm_page_t m; 376174294Sobrien int slot; 377174294Sobrien uint16_t clev; 378174294Sobrien 379174294Sobrien /* 380174294Sobrien * The owner of record for root is not really important because it 381174294Sobrien * will never be used. 382174294Sobrien */ 383174294Sobrien rnode = vm_radix_getroot(rtree); 384174294Sobrien if (rnode == NULL) { 385174294Sobrien rnode = vm_radix_node_get(0, 1, 0); 386174294Sobrien vm_radix_setroot(rtree, rnode); 387174294Sobrien vm_radix_addpage(rnode, index, 0, page); 388174294Sobrien return; 389174294Sobrien } 390174294Sobrien while (rnode != NULL) { 391174294Sobrien if (vm_radix_keybarr(rnode, index) == TRUE) 392174294Sobrien break; 393174294Sobrien slot = vm_radix_slot(index, rnode->rn_clev); 394174294Sobrien m = vm_radix_node_page(rnode->rn_child[slot]); 395174294Sobrien if (m != NULL) { 396174294Sobrien if (m->pindex == index) 397174294Sobrien panic("%s: key %jx is already present", 398174294Sobrien __func__, (uintmax_t)index); 399174294Sobrien clev = vm_radix_keydiff(m->pindex, index); 400174294Sobrien tmp = vm_radix_node_get(vm_radix_trimkey(index, 401174294Sobrien clev - 1), 2, clev); 402174294Sobrien rnode->rn_child[slot] = tmp; 403174294Sobrien vm_radix_addpage(tmp, index, clev, page); 404174294Sobrien vm_radix_addpage(tmp, m->pindex, clev, m); 405174294Sobrien return; 406174294Sobrien } 407174294Sobrien if (rnode->rn_child[slot] == NULL) { 408174294Sobrien rnode->rn_count++; 409174294Sobrien vm_radix_addpage(rnode, index, rnode->rn_clev, page); 410174294Sobrien return; 411174294Sobrien } 412174294Sobrien rnode = rnode->rn_child[slot]; 413174294Sobrien } 414174294Sobrien if (rnode == NULL) 415174294Sobrien panic("%s: path traversal ended unexpectedly", __func__); 416174294Sobrien 417174294Sobrien /* 418174294Sobrien * Scan the trie from the top and find the parent to insert 419174294Sobrien * the new object. 420174294Sobrien */ 421174294Sobrien newind = rnode->rn_owner; 422174294Sobrien clev = vm_radix_keydiff(newind, index); 423174294Sobrien slot = VM_RADIX_COUNT; 424174294Sobrien for (rnode = vm_radix_getroot(rtree); ; rnode = tmp) { 425174294Sobrien KASSERT(rnode != NULL, ("%s: edge cannot be NULL in the scan", 426174294Sobrien __func__)); 427174294Sobrien KASSERT(clev >= rnode->rn_clev, 428174294Sobrien ("%s: unexpected trie depth: clev: %d, rnode->rn_clev: %d", 429174294Sobrien __func__, clev, rnode->rn_clev)); 430174294Sobrien slot = vm_radix_slot(index, rnode->rn_clev); 431174294Sobrien tmp = rnode->rn_child[slot]; 432174294Sobrien KASSERT(tmp != NULL && vm_radix_node_page(tmp) == NULL, 433174294Sobrien ("%s: unexpected lookup interruption", __func__)); 434174294Sobrien if (tmp->rn_clev > clev) 435174294Sobrien break; 436174294Sobrien } 437174294Sobrien KASSERT(rnode != NULL && tmp != NULL && slot < VM_RADIX_COUNT, 438174294Sobrien ("%s: invalid scan parameters rnode: %p, tmp: %p, slot: %d", 439174294Sobrien __func__, (void *)rnode, (void *)tmp, slot)); 440174294Sobrien 441174294Sobrien /* 442174294Sobrien * A new node is needed because the right insertion level is reached. 443174294Sobrien * Setup the new intermediate node and add the 2 children: the 444174294Sobrien * new object and the older edge. 445174294Sobrien */ 446174294Sobrien tmp2 = vm_radix_node_get(vm_radix_trimkey(page->pindex, clev - 1), 2, 447174294Sobrien clev); 448174294Sobrien rnode->rn_child[slot] = tmp2; 449174294Sobrien vm_radix_addpage(tmp2, index, clev, page); 450174294Sobrien slot = vm_radix_slot(newind, clev); 451174294Sobrien tmp2->rn_child[slot] = tmp; 452174294Sobrien} 453174294Sobrien 454174294Sobrien/* 455174294Sobrien * Returns the value stored at the index. If the index is not present 456174294Sobrien * NULL is returned. 457174294Sobrien */ 458174294Sobrienvm_page_t 459174294Sobrienvm_radix_lookup(struct vm_radix *rtree, vm_pindex_t index) 460174294Sobrien{ 461174294Sobrien struct vm_radix_node *rnode; 462174294Sobrien vm_page_t m; 463174294Sobrien int slot; 464174294Sobrien 465174294Sobrien rnode = vm_radix_getroot(rtree); 466174294Sobrien while (rnode != NULL) { 467174294Sobrien if (vm_radix_keybarr(rnode, index) == TRUE) 468174294Sobrien return (NULL); 469174294Sobrien slot = vm_radix_slot(index, rnode->rn_clev); 470174294Sobrien rnode = rnode->rn_child[slot]; 471174294Sobrien m = vm_radix_node_page(rnode); 472174294Sobrien if (m != NULL) { 473174294Sobrien if (m->pindex == index) 474174294Sobrien return (m); 475174294Sobrien else 476174294Sobrien return (NULL); 477174294Sobrien } 478174294Sobrien } 479174294Sobrien return (NULL); 480174294Sobrien} 481174294Sobrien 482174294Sobrien/* 483174294Sobrien * Look up any entry at a position bigger than or equal to index. 484174294Sobrien */ 485174294Sobrienvm_page_t 486174294Sobrienvm_radix_lookup_ge(struct vm_radix *rtree, vm_pindex_t index) 487174294Sobrien{ 488174294Sobrien vm_pindex_t inc; 489174294Sobrien vm_page_t m; 490174294Sobrien struct vm_radix_node *rnode; 491174294Sobrien int slot; 492174294Sobrien uint16_t difflev; 493174294Sobrien boolean_t maplevels[VM_RADIX_LIMIT + 1]; 494174294Sobrien#ifdef INVARIANTS 495174294Sobrien int loops = 0; 496174294Sobrien#endif 497174294Sobrien 498174294Sobrienrestart: 499174294Sobrien KASSERT(++loops < 1000, ("%s: too many loops", __func__)); 500174294Sobrien for (difflev = 0; difflev < (VM_RADIX_LIMIT + 1); difflev++) 501174294Sobrien maplevels[difflev] = FALSE; 502174294Sobrien rnode = vm_radix_getroot(rtree); 503174294Sobrien while (rnode != NULL) { 504174294Sobrien maplevels[rnode->rn_clev] = TRUE; 505174294Sobrien 506174294Sobrien /* 507174294Sobrien * If the keys differ before the current bisection node 508174294Sobrien * the search key might rollback to the earlierst 509174294Sobrien * available bisection node, or to the smaller value 510174294Sobrien * in the current domain (if the owner is bigger than the 511174294Sobrien * search key). 512174294Sobrien * The search for a valid bisection node is helped through 513174294Sobrien * the use of maplevels array which should bring immediately 514174294Sobrien * a lower useful level, skipping holes. 515174294Sobrien */ 516174294Sobrien if (vm_radix_keybarr(rnode, index) == TRUE) { 517174294Sobrien difflev = vm_radix_keydiff(index, rnode->rn_owner); 518174294Sobrien if (index > rnode->rn_owner) { 519174294Sobrien if (vm_radix_addlev(&index, maplevels, 520174294Sobrien difflev) > 0) 521174294Sobrien break; 522174294Sobrien } else 523174294Sobrien index = vm_radix_trimkey(rnode->rn_owner, 524174294Sobrien difflev); 525174294Sobrien goto restart; 526174294Sobrien } 527174294Sobrien slot = vm_radix_slot(index, rnode->rn_clev); 528174294Sobrien m = vm_radix_node_page(rnode->rn_child[slot]); 529174294Sobrien if (m != NULL && m->pindex >= index) 530174294Sobrien return (m); 531174294Sobrien if (rnode->rn_child[slot] != NULL && m == NULL) { 532174294Sobrien rnode = rnode->rn_child[slot]; 533174294Sobrien continue; 534174294Sobrien } 535174294Sobrien 536174294Sobrien /* 537174294Sobrien * Look for an available edge or page within the current 538174294Sobrien * bisection node. 539174294Sobrien */ 540174294Sobrien if (slot < (VM_RADIX_COUNT - 1)) { 541174294Sobrien inc = VM_RADIX_UNITLEVEL(rnode->rn_clev); 542174294Sobrien index = vm_radix_trimkey(index, rnode->rn_clev); 543174294Sobrien index += inc; 544174294Sobrien slot++; 545174294Sobrien for (;; index += inc, slot++) { 546174294Sobrien m = vm_radix_node_page(rnode->rn_child[slot]); 547174294Sobrien if (m != NULL && m->pindex >= index) 548174294Sobrien return (m); 549174294Sobrien if ((rnode->rn_child[slot] != NULL && 550174294Sobrien m == NULL) || slot == (VM_RADIX_COUNT - 1)) 551174294Sobrien break; 552174294Sobrien } 553174294Sobrien } 554174294Sobrien 555174294Sobrien /* 556174294Sobrien * If a valid page or edge, bigger than the search slot, is 557174294Sobrien * found in the traversal, skip to the next higher-level key. 558174294Sobrien */ 559174294Sobrien if (slot == (VM_RADIX_COUNT - 1) && 560174294Sobrien (rnode->rn_child[slot] == NULL || m != NULL)) { 561174294Sobrien if (rnode->rn_clev == 0 || vm_radix_addlev(&index, 562174294Sobrien maplevels, rnode->rn_clev - 1) > 0) 563174294Sobrien break; 564174294Sobrien goto restart; 565174294Sobrien } 566174294Sobrien rnode = rnode->rn_child[slot]; 567174294Sobrien } 568174294Sobrien return (NULL); 569174294Sobrien} 570174294Sobrien 571174294Sobrien/* 572174294Sobrien * Look up any entry at a position less than or equal to index. 573174294Sobrien */ 574174294Sobrienvm_page_t 575174294Sobrienvm_radix_lookup_le(struct vm_radix *rtree, vm_pindex_t index) 576174294Sobrien{ 577174294Sobrien vm_pindex_t inc; 578174294Sobrien vm_page_t m; 579174294Sobrien struct vm_radix_node *rnode; 580174294Sobrien int slot; 581174294Sobrien uint16_t difflev; 582174294Sobrien boolean_t maplevels[VM_RADIX_LIMIT + 1]; 583174294Sobrien#ifdef INVARIANTS 584174294Sobrien int loops = 0; 585174294Sobrien#endif 586174294Sobrien 587174294Sobrienrestart: 588174294Sobrien KASSERT(++loops < 1000, ("%s: too many loops", __func__)); 589174294Sobrien for (difflev = 0; difflev < (VM_RADIX_LIMIT + 1); difflev++) 590174294Sobrien maplevels[difflev] = FALSE; 591174294Sobrien rnode = vm_radix_getroot(rtree); 592174294Sobrien while (rnode != NULL) { 593174294Sobrien maplevels[rnode->rn_clev] = TRUE; 594174294Sobrien 595174294Sobrien /* 596174294Sobrien * If the keys differ before the current bisection node 597174294Sobrien * the search key might rollback to the earlierst 598174294Sobrien * available bisection node, or to the higher value 599174294Sobrien * in the current domain (if the owner is smaller than the 600174294Sobrien * search key). 601174294Sobrien * The search for a valid bisection node is helped through 602174294Sobrien * the use of maplevels array which should bring immediately 603174294Sobrien * a lower useful level, skipping holes. 604174294Sobrien */ 605174294Sobrien if (vm_radix_keybarr(rnode, index) == TRUE) { 606174294Sobrien difflev = vm_radix_keydiff(index, rnode->rn_owner); 607174294Sobrien if (index > rnode->rn_owner) { 608174294Sobrien index = vm_radix_trimkey(rnode->rn_owner, 609174294Sobrien difflev); 610174294Sobrien index |= VM_RADIX_UNITLEVEL(difflev) - 1; 611174294Sobrien } else if (vm_radix_declev(&index, maplevels, 612174294Sobrien difflev) > 0) 613174294Sobrien break; 614174294Sobrien goto restart; 615174294Sobrien } 616174294Sobrien slot = vm_radix_slot(index, rnode->rn_clev); 617174294Sobrien m = vm_radix_node_page(rnode->rn_child[slot]); 618174294Sobrien if (m != NULL && m->pindex <= index) 619174294Sobrien return (m); 620174294Sobrien if (rnode->rn_child[slot] != NULL && m == NULL) { 621174294Sobrien rnode = rnode->rn_child[slot]; 622174294Sobrien continue; 623174294Sobrien } 624174294Sobrien 625174294Sobrien /* 626174294Sobrien * Look for an available edge or page within the current 627174294Sobrien * bisection node. 628174294Sobrien */ 629174294Sobrien if (slot > 0) { 630174294Sobrien inc = VM_RADIX_UNITLEVEL(rnode->rn_clev); 631174294Sobrien index = vm_radix_trimkey(index, rnode->rn_clev); 632174294Sobrien index |= inc - 1; 633174294Sobrien index -= inc; 634174294Sobrien slot--; 635174294Sobrien for (;; index -= inc, slot--) { 636174294Sobrien m = vm_radix_node_page(rnode->rn_child[slot]); 637174294Sobrien if (m != NULL && m->pindex <= index) 638174294Sobrien return (m); 639174294Sobrien if ((rnode->rn_child[slot] != NULL && 640174294Sobrien m == NULL) || slot == 0) 641174294Sobrien break; 642174294Sobrien } 643174294Sobrien } 644174294Sobrien 645174294Sobrien /* 646174294Sobrien * If a valid page or edge, smaller than the search slot, is 647174294Sobrien * found in the traversal, skip to the next higher-level key. 648174294Sobrien */ 649174294Sobrien if (slot == 0 && (rnode->rn_child[slot] == NULL || m != NULL)) { 650174294Sobrien if (rnode->rn_clev == 0 || vm_radix_declev(&index, 651174294Sobrien maplevels, rnode->rn_clev - 1) > 0) 652174294Sobrien break; 653174294Sobrien goto restart; 654174294Sobrien } 655174294Sobrien rnode = rnode->rn_child[slot]; 656174294Sobrien } 657174294Sobrien return (NULL); 658174294Sobrien} 659174294Sobrien 660174294Sobrien/* 661174294Sobrien * Remove the specified index from the tree. 662174294Sobrien * Panics if the key is not present. 663174294Sobrien */ 664174294Sobrienvoid 665174294Sobrienvm_radix_remove(struct vm_radix *rtree, vm_pindex_t index) 666174294Sobrien{ 667174294Sobrien struct vm_radix_node *rnode, *parent; 668174294Sobrien vm_page_t m; 669174294Sobrien int i, slot; 670174294Sobrien 671174294Sobrien parent = NULL; 672174294Sobrien rnode = vm_radix_getroot(rtree); 673174294Sobrien for (;;) { 674174294Sobrien if (rnode == NULL) 675174294Sobrien panic("vm_radix_remove: impossible to locate the key"); 676174294Sobrien slot = vm_radix_slot(index, rnode->rn_clev); 677174294Sobrien m = vm_radix_node_page(rnode->rn_child[slot]); 678174294Sobrien if (m != NULL && m->pindex == index) { 679174294Sobrien rnode->rn_child[slot] = NULL; 680174294Sobrien rnode->rn_count--; 681174294Sobrien if (rnode->rn_count > 1) 682174294Sobrien break; 683174294Sobrien if (parent == NULL) { 684174294Sobrien if (rnode->rn_count == 0) { 685174294Sobrien vm_radix_node_put(rnode); 686174294Sobrien vm_radix_setroot(rtree, NULL); 687174294Sobrien } 688174294Sobrien break; 689174294Sobrien } 690174294Sobrien for (i = 0; i < VM_RADIX_COUNT; i++) 691174294Sobrien if (rnode->rn_child[i] != NULL) 692174294Sobrien break; 693174294Sobrien KASSERT(i != VM_RADIX_COUNT, 694174294Sobrien ("%s: invalid node configuration", __func__)); 695174294Sobrien slot = vm_radix_slot(index, parent->rn_clev); 696174294Sobrien KASSERT(parent->rn_child[slot] == rnode, 697174294Sobrien ("%s: invalid child value", __func__)); 698174294Sobrien parent->rn_child[slot] = rnode->rn_child[i]; 699174294Sobrien rnode->rn_count--; 700174294Sobrien rnode->rn_child[i] = NULL; 701174294Sobrien vm_radix_node_put(rnode); 702174294Sobrien break; 703174294Sobrien } 704174294Sobrien if (m != NULL && m->pindex != index) 705174294Sobrien panic("%s: invalid key found", __func__); 706174294Sobrien parent = rnode; 707174294Sobrien rnode = rnode->rn_child[slot]; 708174294Sobrien } 709174294Sobrien} 710174294Sobrien 711174294Sobrien/* 712174294Sobrien * Remove and free all the nodes from the radix tree. 713174294Sobrien * This function is recrusive but there is a tight control on it as the 714174294Sobrien * maximum depth of the tree is fixed. 715174294Sobrien */ 716174294Sobrienvoid 717174294Sobrienvm_radix_reclaim_allnodes(struct vm_radix *rtree) 718174294Sobrien{ 719174294Sobrien struct vm_radix_node *root; 720174294Sobrien 721174294Sobrien root = vm_radix_getroot(rtree); 722174294Sobrien if (root == NULL) 723174294Sobrien return; 724174294Sobrien vm_radix_reclaim_allnodes_int(root); 725174294Sobrien vm_radix_setroot(rtree, NULL); 726174294Sobrien} 727174294Sobrien 728174294Sobrien#ifdef DDB 729174294Sobrien/* 730174294Sobrien * Show details about the given radix node. 731174294Sobrien */ 732174294SobrienDB_SHOW_COMMAND(radixnode, db_show_radixnode) 733174294Sobrien{ 734174294Sobrien struct vm_radix_node *rnode; 735174294Sobrien int i; 736174294Sobrien 737174294Sobrien if (!have_addr) 738174294Sobrien return; 739174294Sobrien rnode = (struct vm_radix_node *)addr; 740174294Sobrien db_printf("radixnode %p, owner %jx, children count %u, level %u:\n", 741174294Sobrien (void *)rnode, (uintmax_t)rnode->rn_owner, rnode->rn_count, 742174294Sobrien rnode->rn_clev); 743174294Sobrien for (i = 0; i < VM_RADIX_COUNT; i++) 744174294Sobrien if (rnode->rn_child[i] != NULL) 745174294Sobrien db_printf("slot: %d, val: %p, page: %p, clev: %d\n", 746174294Sobrien i, (void *)rnode->rn_child[i], 747174294Sobrien (void *)vm_radix_node_page(rnode->rn_child[i]), 748174294Sobrien rnode->rn_clev); 749174294Sobrien} 750174294Sobrien#endif /* DDB */ 751174294Sobrien