1 /* $NetBSD: uvm_map.c,v 1.413 2024/07/16 16:48:54 uwe Exp $ */ 2 3 /* 4 * Copyright (c) 1997 Charles D. Cranor and Washington University. 5 * Copyright (c) 1991, 1993, The Regents of the University of California. 6 * 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * The Mach Operating System project at Carnegie-Mellon University. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)vm_map.c 8.3 (Berkeley) 1/12/94 37 * from: Id: uvm_map.c,v 1.1.2.27 1998/02/07 01:16:54 chs Exp 38 * 39 * 40 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 41 * All rights reserved. 42 * 43 * Permission to use, copy, modify and distribute this software and 44 * its documentation is hereby granted, provided that both the copyright 45 * notice and this permission notice appear in all copies of the 46 * software, derivative works or modified versions, and any portions 47 * thereof, and that both notices appear in supporting documentation. 48 * 49 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 50 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 51 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 52 * 53 * Carnegie Mellon requests users of this software to return to 54 * 55 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 56 * School of Computer Science 57 * Carnegie Mellon University 58 * Pittsburgh PA 15213-3890 59 * 60 * any improvements or extensions that they make and grant Carnegie the 61 * rights to redistribute these changes. 62 */ 63 64 /* 65 * uvm_map.c: uvm map operations 66 */ 67 68 #include <sys/cdefs.h> 69 __KERNEL_RCSID(0, "$NetBSD: uvm_map.c,v 1.413 2024/07/16 16:48:54 uwe Exp $"); 70 71 #include "opt_ddb.h" 72 #include "opt_pax.h" 73 #include "opt_uvmhist.h" 74 #include "opt_uvm.h" 75 #include "opt_sysv.h" 76 77 #include <sys/param.h> 78 #include <sys/systm.h> 79 #include <sys/mman.h> 80 #include <sys/proc.h> 81 #include <sys/pool.h> 82 #include <sys/kernel.h> 83 #include <sys/mount.h> 84 #include <sys/pax.h> 85 #include <sys/vnode.h> 86 #include <sys/filedesc.h> 87 #include <sys/lockdebug.h> 88 #include <sys/atomic.h> 89 #include <sys/sysctl.h> 90 #ifndef __USER_VA0_IS_SAFE 91 #include <sys/kauth.h> 92 #include "opt_user_va0_disable_default.h" 93 #endif 94 95 #include <sys/shm.h> 96 97 #include <uvm/uvm.h> 98 #include <uvm/uvm_readahead.h> 99 100 #if defined(DDB) || defined(DEBUGPRINT) 101 #include <uvm/uvm_ddb.h> 102 #endif 103 104 #ifdef UVMHIST 105 #ifndef UVMHIST_MAPHIST_SIZE 106 #define UVMHIST_MAPHIST_SIZE 100 107 #endif 108 static struct kern_history_ent maphistbuf[UVMHIST_MAPHIST_SIZE]; 109 UVMHIST_DEFINE(maphist) = UVMHIST_INITIALIZER(maphist, maphistbuf); 110 #endif 111 112 #if !defined(UVMMAP_COUNTERS) 113 114 #define UVMMAP_EVCNT_DEFINE(name) /* nothing */ 115 #define UVMMAP_EVCNT_INCR(ev) /* nothing */ 116 #define UVMMAP_EVCNT_DECR(ev) /* nothing */ 117 118 #else /* defined(UVMMAP_NOCOUNTERS) */ 119 120 #include <sys/evcnt.h> 121 #define UVMMAP_EVCNT_DEFINE(name) \ 122 struct evcnt uvmmap_evcnt_##name = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, \ 123 "uvmmap", #name); \ 124 EVCNT_ATTACH_STATIC(uvmmap_evcnt_##name); 125 #define UVMMAP_EVCNT_INCR(ev) uvmmap_evcnt_##ev.ev_count++ 126 #define UVMMAP_EVCNT_DECR(ev) uvmmap_evcnt_##ev.ev_count-- 127 128 #endif /* defined(UVMMAP_NOCOUNTERS) */ 129 130 UVMMAP_EVCNT_DEFINE(ubackmerge) 131 UVMMAP_EVCNT_DEFINE(uforwmerge) 132 UVMMAP_EVCNT_DEFINE(ubimerge) 133 UVMMAP_EVCNT_DEFINE(unomerge) 134 UVMMAP_EVCNT_DEFINE(kbackmerge) 135 UVMMAP_EVCNT_DEFINE(kforwmerge) 136 UVMMAP_EVCNT_DEFINE(kbimerge) 137 UVMMAP_EVCNT_DEFINE(knomerge) 138 UVMMAP_EVCNT_DEFINE(map_call) 139 UVMMAP_EVCNT_DEFINE(mlk_call) 140 UVMMAP_EVCNT_DEFINE(mlk_hint) 141 UVMMAP_EVCNT_DEFINE(mlk_tree) 142 UVMMAP_EVCNT_DEFINE(mlk_treeloop) 143 144 const char vmmapbsy[] = "vmmapbsy"; 145 146 /* 147 * cache for dynamically-allocated map entries. 148 */ 149 150 static struct pool_cache uvm_map_entry_cache; 151 152 #ifdef PMAP_GROWKERNEL 153 /* 154 * This global represents the end of the kernel virtual address 155 * space. If we want to exceed this, we must grow the kernel 156 * virtual address space dynamically. 157 * 158 * Note, this variable is locked by kernel_map's lock. 159 */ 160 vaddr_t uvm_maxkaddr; 161 #endif 162 163 #ifndef __USER_VA0_IS_SAFE 164 #ifndef __USER_VA0_DISABLE_DEFAULT 165 #define __USER_VA0_DISABLE_DEFAULT 1 166 #endif 167 #ifdef USER_VA0_DISABLE_DEFAULT /* kernel config option overrides */ 168 #undef __USER_VA0_DISABLE_DEFAULT 169 #define __USER_VA0_DISABLE_DEFAULT USER_VA0_DISABLE_DEFAULT 170 #endif 171 int user_va0_disable = __USER_VA0_DISABLE_DEFAULT; 172 #endif 173 174 /* 175 * macros 176 */ 177 178 /* 179 * uvm_map_align_va: round down or up virtual address 180 */ 181 static __inline void 182 uvm_map_align_va(vaddr_t *vap, vsize_t align, int topdown) 183 { 184 185 KASSERT(powerof2(align)); 186 187 if (align != 0 && (*vap & (align - 1)) != 0) { 188 if (topdown) 189 *vap = rounddown2(*vap, align); 190 else 191 *vap = roundup2(*vap, align); 192 } 193 } 194 195 /* 196 * UVM_ET_ISCOMPATIBLE: check some requirements for map entry merging 197 */ 198 extern struct vm_map *pager_map; 199 200 #define UVM_ET_ISCOMPATIBLE(ent, type, uobj, meflags, \ 201 prot, maxprot, inh, adv, wire) \ 202 ((ent)->etype == (type) && \ 203 (((ent)->flags ^ (meflags)) & (UVM_MAP_NOMERGE)) == 0 && \ 204 (ent)->object.uvm_obj == (uobj) && \ 205 (ent)->protection == (prot) && \ 206 (ent)->max_protection == (maxprot) && \ 207 (ent)->inheritance == (inh) && \ 208 (ent)->advice == (adv) && \ 209 (ent)->wired_count == (wire)) 210 211 /* 212 * uvm_map_entry_link: insert entry into a map 213 * 214 * => map must be locked 215 */ 216 #define uvm_map_entry_link(map, after_where, entry) do { \ 217 uvm_mapent_check(entry); \ 218 (map)->nentries++; \ 219 (entry)->prev = (after_where); \ 220 (entry)->next = (after_where)->next; \ 221 (entry)->prev->next = (entry); \ 222 (entry)->next->prev = (entry); \ 223 uvm_rb_insert((map), (entry)); \ 224 } while (/*CONSTCOND*/ 0) 225 226 /* 227 * uvm_map_entry_unlink: remove entry from a map 228 * 229 * => map must be locked 230 */ 231 #define uvm_map_entry_unlink(map, entry) do { \ 232 KASSERT((entry) != (map)->first_free); \ 233 KASSERT((entry) != (map)->hint); \ 234 uvm_mapent_check(entry); \ 235 (map)->nentries--; \ 236 (entry)->next->prev = (entry)->prev; \ 237 (entry)->prev->next = (entry)->next; \ 238 uvm_rb_remove((map), (entry)); \ 239 } while (/*CONSTCOND*/ 0) 240 241 /* 242 * SAVE_HINT: saves the specified entry as the hint for future lookups. 243 * 244 * => map need not be locked. 245 */ 246 #define SAVE_HINT(map, check, value) do { \ 247 if ((map)->hint == (check)) \ 248 (map)->hint = (value); \ 249 } while (/*CONSTCOND*/ 0) 250 251 /* 252 * clear_hints: ensure that hints don't point to the entry. 253 * 254 * => map must be write-locked. 255 */ 256 static void 257 clear_hints(struct vm_map *map, struct vm_map_entry *ent) 258 { 259 260 SAVE_HINT(map, ent, ent->prev); 261 if (map->first_free == ent) { 262 map->first_free = ent->prev; 263 } 264 } 265 266 /* 267 * VM_MAP_RANGE_CHECK: check and correct range 268 * 269 * => map must at least be read locked 270 */ 271 272 #define VM_MAP_RANGE_CHECK(map, start, end) do { \ 273 if (start < vm_map_min(map)) \ 274 start = vm_map_min(map); \ 275 if (end > vm_map_max(map)) \ 276 end = vm_map_max(map); \ 277 if (start > end) \ 278 start = end; \ 279 } while (/*CONSTCOND*/ 0) 280 281 /* 282 * local prototypes 283 */ 284 285 static struct vm_map_entry * 286 uvm_mapent_alloc(struct vm_map *, int); 287 static void uvm_mapent_copy(struct vm_map_entry *, struct vm_map_entry *); 288 static void uvm_mapent_free(struct vm_map_entry *); 289 #if defined(DEBUG) 290 static void _uvm_mapent_check(const struct vm_map_entry *, int); 291 #define uvm_mapent_check(map) _uvm_mapent_check(map, __LINE__) 292 #else /* defined(DEBUG) */ 293 #define uvm_mapent_check(e) /* nothing */ 294 #endif /* defined(DEBUG) */ 295 296 static void uvm_map_entry_unwire(struct vm_map *, struct vm_map_entry *); 297 static void uvm_map_reference_amap(struct vm_map_entry *, int); 298 static int uvm_map_space_avail(vaddr_t *, vsize_t, voff_t, vsize_t, int, 299 int, struct vm_map_entry *); 300 static void uvm_map_unreference_amap(struct vm_map_entry *, int); 301 302 int _uvm_map_sanity(struct vm_map *); 303 int _uvm_tree_sanity(struct vm_map *); 304 static vsize_t uvm_rb_maxgap(const struct vm_map_entry *); 305 306 #define ROOT_ENTRY(map) ((struct vm_map_entry *)(map)->rb_tree.rbt_root) 307 #define LEFT_ENTRY(entry) ((struct vm_map_entry *)(entry)->rb_node.rb_left) 308 #define RIGHT_ENTRY(entry) ((struct vm_map_entry *)(entry)->rb_node.rb_right) 309 #define PARENT_ENTRY(map, entry) \ 310 (ROOT_ENTRY(map) == (entry) \ 311 ? NULL : (struct vm_map_entry *)RB_FATHER(&(entry)->rb_node)) 312 313 /* 314 * These get filled in if/when SYSVSHM shared memory code is loaded 315 * 316 * We do this with function pointers rather the #ifdef SYSVSHM so the 317 * SYSVSHM code can be loaded and unloaded 318 */ 319 void (*uvm_shmexit)(struct vmspace *) = NULL; 320 void (*uvm_shmfork)(struct vmspace *, struct vmspace *) = NULL; 321 322 static int 323 uvm_map_compare_nodes(void *ctx, const void *nparent, const void *nkey) 324 { 325 const struct vm_map_entry *eparent = nparent; 326 const struct vm_map_entry *ekey = nkey; 327 328 KASSERT(eparent->start < ekey->start || eparent->start >= ekey->end); 329 KASSERT(ekey->start < eparent->start || ekey->start >= eparent->end); 330 331 if (eparent->start < ekey->start) 332 return -1; 333 if (eparent->end >= ekey->start) 334 return 1; 335 return 0; 336 } 337 338 static int 339 uvm_map_compare_key(void *ctx, const void *nparent, const void *vkey) 340 { 341 const struct vm_map_entry *eparent = nparent; 342 const vaddr_t va = *(const vaddr_t *) vkey; 343 344 if (eparent->start < va) 345 return -1; 346 if (eparent->end >= va) 347 return 1; 348 return 0; 349 } 350 351 static const rb_tree_ops_t uvm_map_tree_ops = { 352 .rbto_compare_nodes = uvm_map_compare_nodes, 353 .rbto_compare_key = uvm_map_compare_key, 354 .rbto_node_offset = offsetof(struct vm_map_entry, rb_node), 355 .rbto_context = NULL 356 }; 357 358 /* 359 * uvm_rb_gap: return the gap size between our entry and next entry. 360 */ 361 static inline vsize_t 362 uvm_rb_gap(const struct vm_map_entry *entry) 363 { 364 365 KASSERT(entry->next != NULL); 366 return entry->next->start - entry->end; 367 } 368 369 static vsize_t 370 uvm_rb_maxgap(const struct vm_map_entry *entry) 371 { 372 struct vm_map_entry *child; 373 vsize_t maxgap = entry->gap; 374 375 /* 376 * We need maxgap to be the largest gap of us or any of our 377 * descendents. Since each of our children's maxgap is the 378 * cached value of their largest gap of themselves or their 379 * descendents, we can just use that value and avoid recursing 380 * down the tree to calculate it. 381 */ 382 if ((child = LEFT_ENTRY(entry)) != NULL && maxgap < child->maxgap) 383 maxgap = child->maxgap; 384 385 if ((child = RIGHT_ENTRY(entry)) != NULL && maxgap < child->maxgap) 386 maxgap = child->maxgap; 387 388 return maxgap; 389 } 390 391 static void 392 uvm_rb_fixup(struct vm_map *map, struct vm_map_entry *entry) 393 { 394 struct vm_map_entry *parent; 395 396 KASSERT(entry->gap == uvm_rb_gap(entry)); 397 entry->maxgap = uvm_rb_maxgap(entry); 398 399 while ((parent = PARENT_ENTRY(map, entry)) != NULL) { 400 struct vm_map_entry *brother; 401 vsize_t maxgap = parent->gap; 402 unsigned int which; 403 404 KDASSERT(parent->gap == uvm_rb_gap(parent)); 405 if (maxgap < entry->maxgap) 406 maxgap = entry->maxgap; 407 /* 408 * Since we work towards the root, we know entry's maxgap 409 * value is OK, but its brothers may now be out-of-date due 410 * to rebalancing. So refresh it. 411 */ 412 which = RB_POSITION(&entry->rb_node) ^ RB_DIR_OTHER; 413 brother = (struct vm_map_entry *)parent->rb_node.rb_nodes[which]; 414 if (brother != NULL) { 415 KDASSERT(brother->gap == uvm_rb_gap(brother)); 416 brother->maxgap = uvm_rb_maxgap(brother); 417 if (maxgap < brother->maxgap) 418 maxgap = brother->maxgap; 419 } 420 421 parent->maxgap = maxgap; 422 entry = parent; 423 } 424 } 425 426 static void 427 uvm_rb_insert(struct vm_map *map, struct vm_map_entry *entry) 428 { 429 struct vm_map_entry *ret __diagused; 430 431 entry->gap = entry->maxgap = uvm_rb_gap(entry); 432 if (entry->prev != &map->header) 433 entry->prev->gap = uvm_rb_gap(entry->prev); 434 435 ret = rb_tree_insert_node(&map->rb_tree, entry); 436 KASSERTMSG(ret == entry, 437 "uvm_rb_insert: map %p: duplicate entry %p", map, ret); 438 439 /* 440 * If the previous entry is not our immediate left child, then it's an 441 * ancestor and will be fixed up on the way to the root. We don't 442 * have to check entry->prev against &map->header since &map->header 443 * will never be in the tree. 444 */ 445 uvm_rb_fixup(map, 446 LEFT_ENTRY(entry) == entry->prev ? entry->prev : entry); 447 } 448 449 static void 450 uvm_rb_remove(struct vm_map *map, struct vm_map_entry *entry) 451 { 452 struct vm_map_entry *prev_parent = NULL, *next_parent = NULL; 453 454 /* 455 * If we are removing an interior node, then an adjacent node will 456 * be used to replace its position in the tree. Therefore we will 457 * need to fixup the tree starting at the parent of the replacement 458 * node. So record their parents for later use. 459 */ 460 if (entry->prev != &map->header) 461 prev_parent = PARENT_ENTRY(map, entry->prev); 462 if (entry->next != &map->header) 463 next_parent = PARENT_ENTRY(map, entry->next); 464 465 rb_tree_remove_node(&map->rb_tree, entry); 466 467 /* 468 * If the previous node has a new parent, fixup the tree starting 469 * at the previous node's old parent. 470 */ 471 if (entry->prev != &map->header) { 472 /* 473 * Update the previous entry's gap due to our absence. 474 */ 475 entry->prev->gap = uvm_rb_gap(entry->prev); 476 uvm_rb_fixup(map, entry->prev); 477 if (prev_parent != NULL 478 && prev_parent != entry 479 && prev_parent != PARENT_ENTRY(map, entry->prev)) 480 uvm_rb_fixup(map, prev_parent); 481 } 482 483 /* 484 * If the next node has a new parent, fixup the tree starting 485 * at the next node's old parent. 486 */ 487 if (entry->next != &map->header) { 488 uvm_rb_fixup(map, entry->next); 489 if (next_parent != NULL 490 && next_parent != entry 491 && next_parent != PARENT_ENTRY(map, entry->next)) 492 uvm_rb_fixup(map, next_parent); 493 } 494 } 495 496 #if defined(DEBUG) 497 int uvm_debug_check_map = 0; 498 int uvm_debug_check_rbtree = 0; 499 #define uvm_map_check(map, name) \ 500 _uvm_map_check((map), (name), __FILE__, __LINE__) 501 static void 502 _uvm_map_check(struct vm_map *map, const char *name, 503 const char *file, int line) 504 { 505 506 if ((uvm_debug_check_map && _uvm_map_sanity(map)) || 507 (uvm_debug_check_rbtree && _uvm_tree_sanity(map))) { 508 panic("uvm_map_check failed: \"%s\" map=%p (%s:%d)", 509 name, map, file, line); 510 } 511 } 512 #else /* defined(DEBUG) */ 513 #define uvm_map_check(map, name) /* nothing */ 514 #endif /* defined(DEBUG) */ 515 516 #if defined(DEBUG) || defined(DDB) 517 int 518 _uvm_map_sanity(struct vm_map *map) 519 { 520 bool first_free_found = false; 521 bool hint_found = false; 522 const struct vm_map_entry *e; 523 struct vm_map_entry *hint = map->hint; 524 525 e = &map->header; 526 for (;;) { 527 if (map->first_free == e) { 528 first_free_found = true; 529 } else if (!first_free_found && e->next->start > e->end) { 530 printf("first_free %p should be %p\n", 531 map->first_free, e); 532 return -1; 533 } 534 if (hint == e) { 535 hint_found = true; 536 } 537 538 e = e->next; 539 if (e == &map->header) { 540 break; 541 } 542 } 543 if (!first_free_found) { 544 printf("stale first_free\n"); 545 return -1; 546 } 547 if (!hint_found) { 548 printf("stale hint\n"); 549 return -1; 550 } 551 return 0; 552 } 553 554 int 555 _uvm_tree_sanity(struct vm_map *map) 556 { 557 struct vm_map_entry *tmp, *trtmp; 558 int n = 0, i = 1; 559 560 for (tmp = map->header.next; tmp != &map->header; tmp = tmp->next) { 561 if (tmp->gap != uvm_rb_gap(tmp)) { 562 printf("%d/%d gap %#lx != %#lx %s\n", 563 n + 1, map->nentries, 564 (ulong)tmp->gap, (ulong)uvm_rb_gap(tmp), 565 tmp->next == &map->header ? "(last)" : ""); 566 goto error; 567 } 568 /* 569 * If any entries are out of order, tmp->gap will be unsigned 570 * and will likely exceed the size of the map. 571 */ 572 if (tmp->gap >= vm_map_max(map) - vm_map_min(map)) { 573 printf("too large gap %zu\n", (size_t)tmp->gap); 574 goto error; 575 } 576 n++; 577 } 578 579 if (n != map->nentries) { 580 printf("nentries: %d vs %d\n", n, map->nentries); 581 goto error; 582 } 583 584 trtmp = NULL; 585 for (tmp = map->header.next; tmp != &map->header; tmp = tmp->next) { 586 if (tmp->maxgap != uvm_rb_maxgap(tmp)) { 587 printf("maxgap %#lx != %#lx\n", 588 (ulong)tmp->maxgap, 589 (ulong)uvm_rb_maxgap(tmp)); 590 goto error; 591 } 592 if (trtmp != NULL && trtmp->start >= tmp->start) { 593 printf("corrupt: 0x%"PRIxVADDR"x >= 0x%"PRIxVADDR"x\n", 594 trtmp->start, tmp->start); 595 goto error; 596 } 597 598 trtmp = tmp; 599 } 600 601 for (tmp = map->header.next; tmp != &map->header; 602 tmp = tmp->next, i++) { 603 trtmp = rb_tree_iterate(&map->rb_tree, tmp, RB_DIR_LEFT); 604 if (trtmp == NULL) 605 trtmp = &map->header; 606 if (tmp->prev != trtmp) { 607 printf("lookup: %d: %p->prev=%p: %p\n", 608 i, tmp, tmp->prev, trtmp); 609 goto error; 610 } 611 trtmp = rb_tree_iterate(&map->rb_tree, tmp, RB_DIR_RIGHT); 612 if (trtmp == NULL) 613 trtmp = &map->header; 614 if (tmp->next != trtmp) { 615 printf("lookup: %d: %p->next=%p: %p\n", 616 i, tmp, tmp->next, trtmp); 617 goto error; 618 } 619 trtmp = rb_tree_find_node(&map->rb_tree, &tmp->start); 620 if (trtmp != tmp) { 621 printf("lookup: %d: %p - %p: %p\n", i, tmp, trtmp, 622 PARENT_ENTRY(map, tmp)); 623 goto error; 624 } 625 } 626 627 return (0); 628 error: 629 return (-1); 630 } 631 #endif /* defined(DEBUG) || defined(DDB) */ 632 633 /* 634 * vm_map_lock: acquire an exclusive (write) lock on a map. 635 * 636 * => The locking protocol provides for guaranteed upgrade from shared -> 637 * exclusive by whichever thread currently has the map marked busy. 638 * See "LOCKING PROTOCOL NOTES" in uvm_map.h. This is horrible; among 639 * other problems, it defeats any fairness guarantees provided by RW 640 * locks. 641 */ 642 643 void 644 vm_map_lock(struct vm_map *map) 645 { 646 647 for (;;) { 648 rw_enter(&map->lock, RW_WRITER); 649 if (map->busy == NULL || map->busy == curlwp) { 650 break; 651 } 652 mutex_enter(&map->misc_lock); 653 rw_exit(&map->lock); 654 if (map->busy != NULL) { 655 cv_wait(&map->cv, &map->misc_lock); 656 } 657 mutex_exit(&map->misc_lock); 658 } 659 map->timestamp++; 660 } 661 662 /* 663 * vm_map_lock_try: try to lock a map, failing if it is already locked. 664 */ 665 666 bool 667 vm_map_lock_try(struct vm_map *map) 668 { 669 670 if (!rw_tryenter(&map->lock, RW_WRITER)) { 671 return false; 672 } 673 if (map->busy != NULL) { 674 rw_exit(&map->lock); 675 return false; 676 } 677 map->timestamp++; 678 return true; 679 } 680 681 /* 682 * vm_map_unlock: release an exclusive lock on a map. 683 */ 684 685 void 686 vm_map_unlock(struct vm_map *map) 687 { 688 689 KASSERT(rw_write_held(&map->lock)); 690 KASSERT(map->busy == NULL || map->busy == curlwp); 691 rw_exit(&map->lock); 692 } 693 694 /* 695 * vm_map_unbusy: mark the map as unbusy, and wake any waiters that 696 * want an exclusive lock. 697 */ 698 699 void 700 vm_map_unbusy(struct vm_map *map) 701 { 702 703 KASSERT(map->busy == curlwp); 704 705 /* 706 * Safe to clear 'busy' and 'waiters' with only a read lock held: 707 * 708 * o they can only be set with a write lock held 709 * o writers are blocked out with a read or write hold 710 * o at any time, only one thread owns the set of values 711 */ 712 mutex_enter(&map->misc_lock); 713 map->busy = NULL; 714 cv_broadcast(&map->cv); 715 mutex_exit(&map->misc_lock); 716 } 717 718 /* 719 * vm_map_lock_read: acquire a shared (read) lock on a map. 720 */ 721 722 void 723 vm_map_lock_read(struct vm_map *map) 724 { 725 726 rw_enter(&map->lock, RW_READER); 727 } 728 729 /* 730 * vm_map_unlock_read: release a shared lock on a map. 731 */ 732 733 void 734 vm_map_unlock_read(struct vm_map *map) 735 { 736 737 rw_exit(&map->lock); 738 } 739 740 /* 741 * vm_map_busy: mark a map as busy. 742 * 743 * => the caller must hold the map write locked 744 */ 745 746 void 747 vm_map_busy(struct vm_map *map) 748 { 749 750 KASSERT(rw_write_held(&map->lock)); 751 KASSERT(map->busy == NULL); 752 753 map->busy = curlwp; 754 } 755 756 /* 757 * vm_map_locked_p: return true if the map is write locked. 758 * 759 * => only for debug purposes like KASSERTs. 760 * => should not be used to verify that a map is not locked. 761 */ 762 763 bool 764 vm_map_locked_p(struct vm_map *map) 765 { 766 767 return rw_write_held(&map->lock); 768 } 769 770 /* 771 * uvm_mapent_alloc: allocate a map entry 772 */ 773 774 static struct vm_map_entry * 775 uvm_mapent_alloc(struct vm_map *map, int flags) 776 { 777 struct vm_map_entry *me; 778 int pflags = (flags & UVM_FLAG_NOWAIT) ? PR_NOWAIT : PR_WAITOK; 779 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 780 781 me = pool_cache_get(&uvm_map_entry_cache, pflags); 782 if (__predict_false(me == NULL)) { 783 return NULL; 784 } 785 me->flags = 0; 786 787 UVMHIST_LOG(maphist, "<- new entry=%#jx [kentry=%jd]", (uintptr_t)me, 788 (map == kernel_map), 0, 0); 789 return me; 790 } 791 792 /* 793 * uvm_mapent_free: free map entry 794 */ 795 796 static void 797 uvm_mapent_free(struct vm_map_entry *me) 798 { 799 UVMHIST_FUNC(__func__); 800 UVMHIST_CALLARGS(maphist,"<- freeing map entry=%#jx [flags=%#jx]", 801 (uintptr_t)me, me->flags, 0, 0); 802 pool_cache_put(&uvm_map_entry_cache, me); 803 } 804 805 /* 806 * uvm_mapent_copy: copy a map entry, preserving flags 807 */ 808 809 static inline void 810 uvm_mapent_copy(struct vm_map_entry *src, struct vm_map_entry *dst) 811 { 812 813 memcpy(dst, src, sizeof(*dst)); 814 dst->flags = 0; 815 } 816 817 #if defined(DEBUG) 818 static void 819 _uvm_mapent_check(const struct vm_map_entry *entry, int line) 820 { 821 822 if (entry->start >= entry->end) { 823 goto bad; 824 } 825 if (UVM_ET_ISOBJ(entry)) { 826 if (entry->object.uvm_obj == NULL) { 827 goto bad; 828 } 829 } else if (UVM_ET_ISSUBMAP(entry)) { 830 if (entry->object.sub_map == NULL) { 831 goto bad; 832 } 833 } else { 834 if (entry->object.uvm_obj != NULL || 835 entry->object.sub_map != NULL) { 836 goto bad; 837 } 838 } 839 if (!UVM_ET_ISOBJ(entry)) { 840 if (entry->offset != 0) { 841 goto bad; 842 } 843 } 844 845 return; 846 847 bad: 848 panic("%s: bad entry %p, line %d", __func__, entry, line); 849 } 850 #endif /* defined(DEBUG) */ 851 852 /* 853 * uvm_map_entry_unwire: unwire a map entry 854 * 855 * => map should be locked by caller 856 */ 857 858 static inline void 859 uvm_map_entry_unwire(struct vm_map *map, struct vm_map_entry *entry) 860 { 861 862 entry->wired_count = 0; 863 uvm_fault_unwire_locked(map, entry->start, entry->end); 864 } 865 866 867 /* 868 * wrapper for calling amap_ref() 869 */ 870 static inline void 871 uvm_map_reference_amap(struct vm_map_entry *entry, int flags) 872 { 873 874 amap_ref(entry->aref.ar_amap, entry->aref.ar_pageoff, 875 (entry->end - entry->start) >> PAGE_SHIFT, flags); 876 } 877 878 879 /* 880 * wrapper for calling amap_unref() 881 */ 882 static inline void 883 uvm_map_unreference_amap(struct vm_map_entry *entry, int flags) 884 { 885 886 amap_unref(entry->aref.ar_amap, entry->aref.ar_pageoff, 887 (entry->end - entry->start) >> PAGE_SHIFT, flags); 888 } 889 890 891 /* 892 * uvm_map_init: init mapping system at boot time. 893 */ 894 895 void 896 uvm_map_init(void) 897 { 898 /* 899 * first, init logging system. 900 */ 901 902 UVMHIST_FUNC(__func__); 903 UVMHIST_LINK_STATIC(maphist); 904 UVMHIST_LINK_STATIC(pdhist); 905 UVMHIST_CALLED(maphist); 906 UVMHIST_LOG(maphist,"<starting uvm map system>", 0, 0, 0, 0); 907 908 /* 909 * initialize the global lock for kernel map entry. 910 */ 911 912 mutex_init(&uvm_kentry_lock, MUTEX_DRIVER, IPL_VM); 913 } 914 915 /* 916 * uvm_map_init_caches: init mapping system caches. 917 */ 918 void 919 uvm_map_init_caches(void) 920 { 921 /* 922 * initialize caches. 923 */ 924 925 pool_cache_bootstrap(&uvm_map_entry_cache, sizeof(struct vm_map_entry), 926 coherency_unit, 0, PR_LARGECACHE, "vmmpepl", NULL, IPL_NONE, NULL, 927 NULL, NULL); 928 } 929 930 /* 931 * clippers 932 */ 933 934 /* 935 * uvm_mapent_splitadj: adjust map entries for splitting, after uvm_mapent_copy. 936 */ 937 938 static void 939 uvm_mapent_splitadj(struct vm_map_entry *entry1, struct vm_map_entry *entry2, 940 vaddr_t splitat) 941 { 942 vaddr_t adj; 943 944 KASSERT(entry1->start < splitat); 945 KASSERT(splitat < entry1->end); 946 947 adj = splitat - entry1->start; 948 entry1->end = entry2->start = splitat; 949 950 if (entry1->aref.ar_amap) { 951 amap_splitref(&entry1->aref, &entry2->aref, adj); 952 } 953 if (UVM_ET_ISSUBMAP(entry1)) { 954 /* ... unlikely to happen, but play it safe */ 955 uvm_map_reference(entry1->object.sub_map); 956 } else if (UVM_ET_ISOBJ(entry1)) { 957 KASSERT(entry1->object.uvm_obj != NULL); /* suppress coverity */ 958 entry2->offset += adj; 959 if (entry1->object.uvm_obj->pgops && 960 entry1->object.uvm_obj->pgops->pgo_reference) 961 entry1->object.uvm_obj->pgops->pgo_reference( 962 entry1->object.uvm_obj); 963 } 964 } 965 966 /* 967 * uvm_map_clip_start: ensure that the entry begins at or after 968 * the starting address, if it doesn't we split the entry. 969 * 970 * => caller should use UVM_MAP_CLIP_START macro rather than calling 971 * this directly 972 * => map must be locked by caller 973 */ 974 975 void 976 uvm_map_clip_start(struct vm_map *map, struct vm_map_entry *entry, 977 vaddr_t start) 978 { 979 struct vm_map_entry *new_entry; 980 981 /* uvm_map_simplify_entry(map, entry); */ /* XXX */ 982 983 uvm_map_check(map, "clip_start entry"); 984 uvm_mapent_check(entry); 985 986 /* 987 * Split off the front portion. note that we must insert the new 988 * entry BEFORE this one, so that this entry has the specified 989 * starting address. 990 */ 991 new_entry = uvm_mapent_alloc(map, 0); 992 uvm_mapent_copy(entry, new_entry); /* entry -> new_entry */ 993 uvm_mapent_splitadj(new_entry, entry, start); 994 uvm_map_entry_link(map, entry->prev, new_entry); 995 996 uvm_map_check(map, "clip_start leave"); 997 } 998 999 /* 1000 * uvm_map_clip_end: ensure that the entry ends at or before 1001 * the ending address, if it does't we split the reference 1002 * 1003 * => caller should use UVM_MAP_CLIP_END macro rather than calling 1004 * this directly 1005 * => map must be locked by caller 1006 */ 1007 1008 void 1009 uvm_map_clip_end(struct vm_map *map, struct vm_map_entry *entry, vaddr_t end) 1010 { 1011 struct vm_map_entry *new_entry; 1012 1013 uvm_map_check(map, "clip_end entry"); 1014 uvm_mapent_check(entry); 1015 1016 /* 1017 * Create a new entry and insert it 1018 * AFTER the specified entry 1019 */ 1020 new_entry = uvm_mapent_alloc(map, 0); 1021 uvm_mapent_copy(entry, new_entry); /* entry -> new_entry */ 1022 uvm_mapent_splitadj(entry, new_entry, end); 1023 uvm_map_entry_link(map, entry, new_entry); 1024 1025 uvm_map_check(map, "clip_end leave"); 1026 } 1027 1028 /* 1029 * M A P - m a i n e n t r y p o i n t 1030 */ 1031 /* 1032 * uvm_map: establish a valid mapping in a map 1033 * 1034 * => assume startp is page aligned. 1035 * => assume size is a multiple of PAGE_SIZE. 1036 * => assume sys_mmap provides enough of a "hint" to have us skip 1037 * over text/data/bss area. 1038 * => map must be unlocked (we will lock it) 1039 * => <uobj,uoffset> value meanings (4 cases): 1040 * [1] <NULL,uoffset> == uoffset is a hint for PMAP_PREFER 1041 * [2] <NULL,UVM_UNKNOWN_OFFSET> == don't PMAP_PREFER 1042 * [3] <uobj,uoffset> == normal mapping 1043 * [4] <uobj,UVM_UNKNOWN_OFFSET> == uvm_map finds offset based on VA 1044 * 1045 * case [4] is for kernel mappings where we don't know the offset until 1046 * we've found a virtual address. note that kernel object offsets are 1047 * always relative to vm_map_min(kernel_map). 1048 * 1049 * => if `align' is non-zero, we align the virtual address to the specified 1050 * alignment. 1051 * this is provided as a mechanism for large pages. 1052 * 1053 * => XXXCDC: need way to map in external amap? 1054 */ 1055 1056 int 1057 uvm_map(struct vm_map *map, vaddr_t *startp /* IN/OUT */, vsize_t size, 1058 struct uvm_object *uobj, voff_t uoffset, vsize_t align, uvm_flag_t flags) 1059 { 1060 struct uvm_map_args args; 1061 struct vm_map_entry *new_entry; 1062 int error; 1063 1064 KASSERT((size & PAGE_MASK) == 0); 1065 KASSERT((flags & UVM_FLAG_FIXED) == 0 || align == 0); 1066 1067 /* 1068 * for pager_map, allocate the new entry first to avoid sleeping 1069 * for memory while we have the map locked. 1070 */ 1071 1072 new_entry = NULL; 1073 if (map == pager_map) { 1074 new_entry = uvm_mapent_alloc(map, (flags & UVM_FLAG_NOWAIT)); 1075 if (__predict_false(new_entry == NULL)) 1076 return ENOMEM; 1077 } 1078 if (map == pager_map) 1079 flags |= UVM_FLAG_NOMERGE; 1080 1081 error = uvm_map_prepare(map, *startp, size, uobj, uoffset, align, 1082 flags, &args); 1083 if (!error) { 1084 error = uvm_map_enter(map, &args, new_entry); 1085 *startp = args.uma_start; 1086 } else if (new_entry) { 1087 uvm_mapent_free(new_entry); 1088 } 1089 1090 #if defined(DEBUG) 1091 if (!error && VM_MAP_IS_KERNEL(map) && (flags & UVM_FLAG_NOWAIT) == 0) { 1092 uvm_km_check_empty(map, *startp, *startp + size); 1093 } 1094 #endif /* defined(DEBUG) */ 1095 1096 return error; 1097 } 1098 1099 /* 1100 * uvm_map_prepare: 1101 * 1102 * called with map unlocked. 1103 * on success, returns the map locked. 1104 */ 1105 1106 int 1107 uvm_map_prepare(struct vm_map *map, vaddr_t start, vsize_t size, 1108 struct uvm_object *uobj, voff_t uoffset, vsize_t align, uvm_flag_t flags, 1109 struct uvm_map_args *args) 1110 { 1111 struct vm_map_entry *prev_entry; 1112 vm_prot_t prot = UVM_PROTECTION(flags); 1113 vm_prot_t maxprot = UVM_MAXPROTECTION(flags); 1114 1115 UVMHIST_FUNC(__func__); 1116 UVMHIST_CALLARGS(maphist, "(map=%#jx, start=%#jx, size=%jx, flags=%#jx)", 1117 (uintptr_t)map, start, size, flags); 1118 UVMHIST_LOG(maphist, " uobj/offset %#jx/%jd", (uintptr_t)uobj, 1119 uoffset,0,0); 1120 1121 /* 1122 * detect a popular device driver bug. 1123 */ 1124 1125 KASSERT(doing_shutdown || curlwp != NULL); 1126 1127 /* 1128 * zero-sized mapping doesn't make any sense. 1129 */ 1130 KASSERT(size > 0); 1131 1132 KASSERT((~flags & (UVM_FLAG_NOWAIT | UVM_FLAG_WAITVA)) != 0); 1133 1134 uvm_map_check(map, "map entry"); 1135 1136 /* 1137 * check sanity of protection code 1138 */ 1139 1140 if ((prot & maxprot) != prot) { 1141 UVMHIST_LOG(maphist, "<- prot. failure: prot=%#jx, max=%#jx", 1142 prot, maxprot,0,0); 1143 return EACCES; 1144 } 1145 1146 /* 1147 * figure out where to put new VM range 1148 */ 1149 retry: 1150 if (vm_map_lock_try(map) == false) { 1151 if ((flags & UVM_FLAG_TRYLOCK) != 0) { 1152 return EAGAIN; 1153 } 1154 vm_map_lock(map); /* could sleep here */ 1155 } 1156 if (flags & UVM_FLAG_UNMAP) { 1157 KASSERT(flags & UVM_FLAG_FIXED); 1158 KASSERT((flags & UVM_FLAG_NOWAIT) == 0); 1159 1160 /* 1161 * Set prev_entry to what it will need to be after any existing 1162 * entries are removed later in uvm_map_enter(). 1163 */ 1164 1165 if (uvm_map_lookup_entry(map, start, &prev_entry)) { 1166 if (start == prev_entry->start) 1167 prev_entry = prev_entry->prev; 1168 else 1169 UVM_MAP_CLIP_END(map, prev_entry, start); 1170 SAVE_HINT(map, map->hint, prev_entry); 1171 } 1172 } else { 1173 prev_entry = uvm_map_findspace(map, start, size, &start, 1174 uobj, uoffset, align, flags); 1175 } 1176 if (prev_entry == NULL) { 1177 unsigned int timestamp; 1178 1179 timestamp = map->timestamp; 1180 UVMHIST_LOG(maphist,"waiting va timestamp=%#jx", 1181 timestamp,0,0,0); 1182 map->flags |= VM_MAP_WANTVA; 1183 vm_map_unlock(map); 1184 1185 /* 1186 * try to reclaim kva and wait until someone does unmap. 1187 * fragile locking here, so we awaken every second to 1188 * recheck the condition. 1189 */ 1190 1191 mutex_enter(&map->misc_lock); 1192 while ((map->flags & VM_MAP_WANTVA) != 0 && 1193 map->timestamp == timestamp) { 1194 if ((flags & UVM_FLAG_WAITVA) == 0) { 1195 mutex_exit(&map->misc_lock); 1196 UVMHIST_LOG(maphist, 1197 "<- uvm_map_findspace failed!", 0,0,0,0); 1198 return ENOMEM; 1199 } else { 1200 cv_timedwait(&map->cv, &map->misc_lock, hz); 1201 } 1202 } 1203 mutex_exit(&map->misc_lock); 1204 goto retry; 1205 } 1206 1207 #ifdef PMAP_GROWKERNEL 1208 /* 1209 * If the kernel pmap can't map the requested space, 1210 * then allocate more resources for it. 1211 */ 1212 if (map == kernel_map && uvm_maxkaddr < (start + size)) 1213 uvm_maxkaddr = pmap_growkernel(start + size); 1214 #endif 1215 1216 UVMMAP_EVCNT_INCR(map_call); 1217 1218 /* 1219 * if uobj is null, then uoffset is either a VAC hint for PMAP_PREFER 1220 * [typically from uvm_map_reserve] or it is UVM_UNKNOWN_OFFSET. in 1221 * either case we want to zero it before storing it in the map entry 1222 * (because it looks strange and confusing when debugging...) 1223 * 1224 * if uobj is not null 1225 * if uoffset is not UVM_UNKNOWN_OFFSET then we have a normal mapping 1226 * and we do not need to change uoffset. 1227 * if uoffset is UVM_UNKNOWN_OFFSET then we need to find the offset 1228 * now (based on the starting address of the map). this case is 1229 * for kernel object mappings where we don't know the offset until 1230 * the virtual address is found (with uvm_map_findspace). the 1231 * offset is the distance we are from the start of the map. 1232 */ 1233 1234 if (uobj == NULL) { 1235 uoffset = 0; 1236 } else { 1237 if (uoffset == UVM_UNKNOWN_OFFSET) { 1238 KASSERT(UVM_OBJ_IS_KERN_OBJECT(uobj)); 1239 uoffset = start - vm_map_min(kernel_map); 1240 } 1241 } 1242 1243 args->uma_flags = flags; 1244 args->uma_prev = prev_entry; 1245 args->uma_start = start; 1246 args->uma_size = size; 1247 args->uma_uobj = uobj; 1248 args->uma_uoffset = uoffset; 1249 1250 UVMHIST_LOG(maphist, "<- done!", 0,0,0,0); 1251 return 0; 1252 } 1253 1254 /* 1255 * uvm_map_enter: 1256 * 1257 * called with map locked. 1258 * unlock the map before returning. 1259 */ 1260 1261 int 1262 uvm_map_enter(struct vm_map *map, const struct uvm_map_args *args, 1263 struct vm_map_entry *new_entry) 1264 { 1265 struct vm_map_entry *prev_entry = args->uma_prev; 1266 struct vm_map_entry *dead = NULL, *dead_entries = NULL; 1267 1268 const uvm_flag_t flags = args->uma_flags; 1269 const vm_prot_t prot = UVM_PROTECTION(flags); 1270 const vm_prot_t maxprot = UVM_MAXPROTECTION(flags); 1271 const vm_inherit_t inherit = UVM_INHERIT(flags); 1272 const int amapwaitflag = (flags & UVM_FLAG_NOWAIT) ? 1273 AMAP_EXTEND_NOWAIT : 0; 1274 const int advice = UVM_ADVICE(flags); 1275 1276 vaddr_t start = args->uma_start; 1277 vsize_t size = args->uma_size; 1278 struct uvm_object *uobj = args->uma_uobj; 1279 voff_t uoffset = args->uma_uoffset; 1280 1281 const int kmap = (vm_map_pmap(map) == pmap_kernel()); 1282 int merged = 0; 1283 int error; 1284 int newetype; 1285 1286 UVMHIST_FUNC(__func__); 1287 UVMHIST_CALLARGS(maphist, "(map=%#jx, start=%#jx, size=%ju, flags=%#jx)", 1288 (uintptr_t)map, start, size, flags); 1289 UVMHIST_LOG(maphist, " uobj/offset %#jx/%jd", (uintptr_t)uobj, 1290 uoffset,0,0); 1291 1292 KASSERT(map->hint == prev_entry); /* bimerge case assumes this */ 1293 KASSERT(vm_map_locked_p(map)); 1294 KASSERT((flags & (UVM_FLAG_NOWAIT | UVM_FLAG_UNMAP)) != 1295 (UVM_FLAG_NOWAIT | UVM_FLAG_UNMAP)); 1296 1297 if (uobj) 1298 newetype = UVM_ET_OBJ; 1299 else 1300 newetype = 0; 1301 1302 if (flags & UVM_FLAG_COPYONW) { 1303 newetype |= UVM_ET_COPYONWRITE; 1304 if ((flags & UVM_FLAG_OVERLAY) == 0) 1305 newetype |= UVM_ET_NEEDSCOPY; 1306 } 1307 1308 /* 1309 * For mappings with unmap, remove any old entries now. Adding the new 1310 * entry cannot fail because that can only happen if UVM_FLAG_NOWAIT 1311 * is set, and we do not support nowait and unmap together. 1312 */ 1313 1314 if (flags & UVM_FLAG_UNMAP) { 1315 KASSERT(flags & UVM_FLAG_FIXED); 1316 uvm_unmap_remove(map, start, start + size, &dead_entries, 0); 1317 #ifdef DEBUG 1318 struct vm_map_entry *tmp_entry __diagused; 1319 bool rv __diagused; 1320 1321 rv = uvm_map_lookup_entry(map, start, &tmp_entry); 1322 KASSERT(!rv); 1323 KASSERTMSG(prev_entry == tmp_entry, 1324 "args %p prev_entry %p tmp_entry %p", 1325 args, prev_entry, tmp_entry); 1326 #endif 1327 SAVE_HINT(map, map->hint, prev_entry); 1328 } 1329 1330 /* 1331 * try and insert in map by extending previous entry, if possible. 1332 * XXX: we don't try and pull back the next entry. might be useful 1333 * for a stack, but we are currently allocating our stack in advance. 1334 */ 1335 1336 if (flags & UVM_FLAG_NOMERGE) 1337 goto nomerge; 1338 1339 if (prev_entry->end == start && 1340 prev_entry != &map->header && 1341 UVM_ET_ISCOMPATIBLE(prev_entry, newetype, uobj, 0, 1342 prot, maxprot, inherit, advice, 0)) { 1343 1344 if (uobj && prev_entry->offset + 1345 (prev_entry->end - prev_entry->start) != uoffset) 1346 goto forwardmerge; 1347 1348 /* 1349 * can't extend a shared amap. note: no need to lock amap to 1350 * look at refs since we don't care about its exact value. 1351 * if it is one (i.e. we have only reference) it will stay there 1352 */ 1353 1354 if (prev_entry->aref.ar_amap && 1355 amap_refs(prev_entry->aref.ar_amap) != 1) { 1356 goto forwardmerge; 1357 } 1358 1359 if (prev_entry->aref.ar_amap) { 1360 error = amap_extend(prev_entry, size, 1361 amapwaitflag | AMAP_EXTEND_FORWARDS); 1362 if (error) 1363 goto nomerge; 1364 } 1365 1366 if (kmap) { 1367 UVMMAP_EVCNT_INCR(kbackmerge); 1368 } else { 1369 UVMMAP_EVCNT_INCR(ubackmerge); 1370 } 1371 UVMHIST_LOG(maphist," starting back merge", 0, 0, 0, 0); 1372 1373 /* 1374 * drop our reference to uobj since we are extending a reference 1375 * that we already have (the ref count can not drop to zero). 1376 */ 1377 1378 if (uobj && uobj->pgops->pgo_detach) 1379 uobj->pgops->pgo_detach(uobj); 1380 1381 /* 1382 * Now that we've merged the entries, note that we've grown 1383 * and our gap has shrunk. Then fix the tree. 1384 */ 1385 prev_entry->end += size; 1386 prev_entry->gap -= size; 1387 uvm_rb_fixup(map, prev_entry); 1388 1389 uvm_map_check(map, "map backmerged"); 1390 1391 UVMHIST_LOG(maphist,"<- done (via backmerge)!", 0, 0, 0, 0); 1392 merged++; 1393 } 1394 1395 forwardmerge: 1396 if (prev_entry->next->start == (start + size) && 1397 prev_entry->next != &map->header && 1398 UVM_ET_ISCOMPATIBLE(prev_entry->next, newetype, uobj, 0, 1399 prot, maxprot, inherit, advice, 0)) { 1400 1401 if (uobj && prev_entry->next->offset != uoffset + size) 1402 goto nomerge; 1403 1404 /* 1405 * can't extend a shared amap. note: no need to lock amap to 1406 * look at refs since we don't care about its exact value. 1407 * if it is one (i.e. we have only reference) it will stay there. 1408 * 1409 * note that we also can't merge two amaps, so if we 1410 * merged with the previous entry which has an amap, 1411 * and the next entry also has an amap, we give up. 1412 * 1413 * Interesting cases: 1414 * amap, new, amap -> give up second merge (single fwd extend) 1415 * amap, new, none -> double forward extend (extend again here) 1416 * none, new, amap -> double backward extend (done here) 1417 * uobj, new, amap -> single backward extend (done here) 1418 * 1419 * XXX should we attempt to deal with someone refilling 1420 * the deallocated region between two entries that are 1421 * backed by the same amap (ie, arefs is 2, "prev" and 1422 * "next" refer to it, and adding this allocation will 1423 * close the hole, thus restoring arefs to 1 and 1424 * deallocating the "next" vm_map_entry)? -- @@@ 1425 */ 1426 1427 if (prev_entry->next->aref.ar_amap && 1428 (amap_refs(prev_entry->next->aref.ar_amap) != 1 || 1429 (merged && prev_entry->aref.ar_amap))) { 1430 goto nomerge; 1431 } 1432 1433 if (merged) { 1434 /* 1435 * Try to extend the amap of the previous entry to 1436 * cover the next entry as well. If it doesn't work 1437 * just skip on, don't actually give up, since we've 1438 * already completed the back merge. 1439 */ 1440 if (prev_entry->aref.ar_amap) { 1441 if (amap_extend(prev_entry, 1442 prev_entry->next->end - 1443 prev_entry->next->start, 1444 amapwaitflag | AMAP_EXTEND_FORWARDS)) 1445 goto nomerge; 1446 } 1447 1448 /* 1449 * Try to extend the amap of the *next* entry 1450 * back to cover the new allocation *and* the 1451 * previous entry as well (the previous merge 1452 * didn't have an amap already otherwise we 1453 * wouldn't be checking here for an amap). If 1454 * it doesn't work just skip on, again, don't 1455 * actually give up, since we've already 1456 * completed the back merge. 1457 */ 1458 else if (prev_entry->next->aref.ar_amap) { 1459 if (amap_extend(prev_entry->next, 1460 prev_entry->end - 1461 prev_entry->start, 1462 amapwaitflag | AMAP_EXTEND_BACKWARDS)) 1463 goto nomerge; 1464 } 1465 } else { 1466 /* 1467 * Pull the next entry's amap backwards to cover this 1468 * new allocation. 1469 */ 1470 if (prev_entry->next->aref.ar_amap) { 1471 error = amap_extend(prev_entry->next, size, 1472 amapwaitflag | AMAP_EXTEND_BACKWARDS); 1473 if (error) 1474 goto nomerge; 1475 } 1476 } 1477 1478 if (merged) { 1479 if (kmap) { 1480 UVMMAP_EVCNT_DECR(kbackmerge); 1481 UVMMAP_EVCNT_INCR(kbimerge); 1482 } else { 1483 UVMMAP_EVCNT_DECR(ubackmerge); 1484 UVMMAP_EVCNT_INCR(ubimerge); 1485 } 1486 } else { 1487 if (kmap) { 1488 UVMMAP_EVCNT_INCR(kforwmerge); 1489 } else { 1490 UVMMAP_EVCNT_INCR(uforwmerge); 1491 } 1492 } 1493 UVMHIST_LOG(maphist," starting forward merge", 0, 0, 0, 0); 1494 1495 /* 1496 * drop our reference to uobj since we are extending a reference 1497 * that we already have (the ref count can not drop to zero). 1498 */ 1499 if (uobj && uobj->pgops->pgo_detach) 1500 uobj->pgops->pgo_detach(uobj); 1501 1502 if (merged) { 1503 dead = prev_entry->next; 1504 prev_entry->end = dead->end; 1505 uvm_map_entry_unlink(map, dead); 1506 if (dead->aref.ar_amap != NULL) { 1507 prev_entry->aref = dead->aref; 1508 dead->aref.ar_amap = NULL; 1509 } 1510 } else { 1511 prev_entry->next->start -= size; 1512 if (prev_entry != &map->header) { 1513 prev_entry->gap -= size; 1514 KASSERT(prev_entry->gap == uvm_rb_gap(prev_entry)); 1515 uvm_rb_fixup(map, prev_entry); 1516 } 1517 if (uobj) 1518 prev_entry->next->offset = uoffset; 1519 } 1520 1521 uvm_map_check(map, "map forwardmerged"); 1522 1523 UVMHIST_LOG(maphist,"<- done forwardmerge", 0, 0, 0, 0); 1524 merged++; 1525 } 1526 1527 nomerge: 1528 if (!merged) { 1529 UVMHIST_LOG(maphist," allocating new map entry", 0, 0, 0, 0); 1530 if (kmap) { 1531 UVMMAP_EVCNT_INCR(knomerge); 1532 } else { 1533 UVMMAP_EVCNT_INCR(unomerge); 1534 } 1535 1536 /* 1537 * allocate new entry and link it in. 1538 */ 1539 1540 if (new_entry == NULL) { 1541 new_entry = uvm_mapent_alloc(map, 1542 (flags & UVM_FLAG_NOWAIT)); 1543 if (__predict_false(new_entry == NULL)) { 1544 error = ENOMEM; 1545 goto done; 1546 } 1547 } 1548 new_entry->start = start; 1549 new_entry->end = new_entry->start + size; 1550 new_entry->object.uvm_obj = uobj; 1551 new_entry->offset = uoffset; 1552 1553 new_entry->etype = newetype; 1554 1555 if (flags & UVM_FLAG_NOMERGE) { 1556 new_entry->flags |= UVM_MAP_NOMERGE; 1557 } 1558 1559 new_entry->protection = prot; 1560 new_entry->max_protection = maxprot; 1561 new_entry->inheritance = inherit; 1562 new_entry->wired_count = 0; 1563 new_entry->advice = advice; 1564 if (flags & UVM_FLAG_OVERLAY) { 1565 1566 /* 1567 * to_add: for BSS we overallocate a little since we 1568 * are likely to extend 1569 */ 1570 1571 vaddr_t to_add = (flags & UVM_FLAG_AMAPPAD) ? 1572 UVM_AMAP_CHUNK << PAGE_SHIFT : 0; 1573 struct vm_amap *amap = amap_alloc(size, to_add, 1574 (flags & UVM_FLAG_NOWAIT)); 1575 if (__predict_false(amap == NULL)) { 1576 error = ENOMEM; 1577 goto done; 1578 } 1579 new_entry->aref.ar_pageoff = 0; 1580 new_entry->aref.ar_amap = amap; 1581 } else { 1582 new_entry->aref.ar_pageoff = 0; 1583 new_entry->aref.ar_amap = NULL; 1584 } 1585 uvm_map_entry_link(map, prev_entry, new_entry); 1586 1587 /* 1588 * Update the free space hint 1589 */ 1590 1591 if ((map->first_free == prev_entry) && 1592 (prev_entry->end >= new_entry->start)) 1593 map->first_free = new_entry; 1594 1595 new_entry = NULL; 1596 } 1597 1598 map->size += size; 1599 1600 UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0); 1601 1602 error = 0; 1603 1604 done: 1605 vm_map_unlock(map); 1606 1607 if (new_entry) { 1608 uvm_mapent_free(new_entry); 1609 } 1610 if (dead) { 1611 KDASSERT(merged); 1612 uvm_mapent_free(dead); 1613 } 1614 if (dead_entries) 1615 uvm_unmap_detach(dead_entries, 0); 1616 1617 return error; 1618 } 1619 1620 /* 1621 * uvm_map_lookup_entry_bytree: lookup an entry in tree 1622 */ 1623 1624 static inline bool 1625 uvm_map_lookup_entry_bytree(struct vm_map *map, vaddr_t address, 1626 struct vm_map_entry **entry /* OUT */) 1627 { 1628 struct vm_map_entry *prev = &map->header; 1629 struct vm_map_entry *cur = ROOT_ENTRY(map); 1630 1631 while (cur) { 1632 UVMMAP_EVCNT_INCR(mlk_treeloop); 1633 if (address >= cur->start) { 1634 if (address < cur->end) { 1635 *entry = cur; 1636 return true; 1637 } 1638 prev = cur; 1639 cur = RIGHT_ENTRY(cur); 1640 } else 1641 cur = LEFT_ENTRY(cur); 1642 } 1643 *entry = prev; 1644 return false; 1645 } 1646 1647 /* 1648 * uvm_map_lookup_entry: find map entry at or before an address 1649 * 1650 * => map must at least be read-locked by caller 1651 * => entry is returned in "entry" 1652 * => return value is true if address is in the returned entry 1653 */ 1654 1655 bool 1656 uvm_map_lookup_entry(struct vm_map *map, vaddr_t address, 1657 struct vm_map_entry **entry /* OUT */) 1658 { 1659 struct vm_map_entry *cur; 1660 UVMHIST_FUNC(__func__); 1661 UVMHIST_CALLARGS(maphist,"(map=%#jx,addr=%#jx,ent=%#jx)", 1662 (uintptr_t)map, address, (uintptr_t)entry, 0); 1663 1664 /* 1665 * make a quick check to see if we are already looking at 1666 * the entry we want (which is usually the case). note also 1667 * that we don't need to save the hint here... it is the 1668 * same hint (unless we are at the header, in which case the 1669 * hint didn't buy us anything anyway). 1670 */ 1671 1672 cur = map->hint; 1673 UVMMAP_EVCNT_INCR(mlk_call); 1674 if (cur != &map->header && 1675 address >= cur->start && cur->end > address) { 1676 UVMMAP_EVCNT_INCR(mlk_hint); 1677 *entry = cur; 1678 UVMHIST_LOG(maphist,"<- got it via hint (%#jx)", 1679 (uintptr_t)cur, 0, 0, 0); 1680 uvm_mapent_check(*entry); 1681 return (true); 1682 } 1683 uvm_map_check(map, __func__); 1684 1685 /* 1686 * lookup in the tree. 1687 */ 1688 1689 UVMMAP_EVCNT_INCR(mlk_tree); 1690 if (__predict_true(uvm_map_lookup_entry_bytree(map, address, entry))) { 1691 SAVE_HINT(map, map->hint, *entry); 1692 UVMHIST_LOG(maphist,"<- search got it (%#jx)", 1693 (uintptr_t)cur, 0, 0, 0); 1694 KDASSERT((*entry)->start <= address); 1695 KDASSERT(address < (*entry)->end); 1696 uvm_mapent_check(*entry); 1697 return (true); 1698 } 1699 1700 SAVE_HINT(map, map->hint, *entry); 1701 UVMHIST_LOG(maphist,"<- failed!",0,0,0,0); 1702 KDASSERT((*entry) == &map->header || (*entry)->end <= address); 1703 KDASSERT((*entry)->next == &map->header || 1704 address < (*entry)->next->start); 1705 return (false); 1706 } 1707 1708 /* 1709 * See if the range between start and start + length fits in the gap 1710 * entry->next->start and entry->end. Returns 1 if fits, 0 if doesn't 1711 * fit, and -1 address wraps around. 1712 */ 1713 static int 1714 uvm_map_space_avail(vaddr_t *start, vsize_t length, voff_t uoffset, 1715 vsize_t align, int flags, int topdown, struct vm_map_entry *entry) 1716 { 1717 vaddr_t end; 1718 1719 #ifdef PMAP_PREFER 1720 /* 1721 * push start address forward as needed to avoid VAC alias problems. 1722 * we only do this if a valid offset is specified. 1723 */ 1724 1725 if (uoffset != UVM_UNKNOWN_OFFSET) 1726 PMAP_PREFER(uoffset, start, length, topdown); 1727 #endif 1728 if ((flags & UVM_FLAG_COLORMATCH) != 0) { 1729 KASSERT(align < uvmexp.ncolors); 1730 if (uvmexp.ncolors > 1) { 1731 const u_int colormask = uvmexp.colormask; 1732 const u_int colorsize = colormask + 1; 1733 vaddr_t hint = atop(*start); 1734 const u_int color = hint & colormask; 1735 if (color != align) { 1736 hint -= color; /* adjust to color boundary */ 1737 KASSERT((hint & colormask) == 0); 1738 if (topdown) { 1739 if (align > color) 1740 hint -= colorsize; 1741 } else { 1742 if (align < color) 1743 hint += colorsize; 1744 } 1745 *start = ptoa(hint + align); /* adjust to color */ 1746 } 1747 } 1748 } else { 1749 KASSERT(powerof2(align)); 1750 uvm_map_align_va(start, align, topdown); 1751 /* 1752 * XXX Should we PMAP_PREFER() here again? 1753 * eh...i think we're okay 1754 */ 1755 } 1756 1757 /* 1758 * Find the end of the proposed new region. Be sure we didn't 1759 * wrap around the address; if so, we lose. Otherwise, if the 1760 * proposed new region fits before the next entry, we win. 1761 */ 1762 1763 end = *start + length; 1764 if (end < *start) 1765 return (-1); 1766 1767 if (entry->next->start >= end && *start >= entry->end) 1768 return (1); 1769 1770 return (0); 1771 } 1772 1773 static void 1774 uvm_findspace_invariants(struct vm_map *map, vaddr_t orig_hint, vaddr_t length, 1775 struct uvm_object *uobj, voff_t uoffset, vsize_t align, int flags, 1776 vaddr_t hint, struct vm_map_entry *entry, int line) 1777 { 1778 const int topdown = map->flags & VM_MAP_TOPDOWN; 1779 const int hint_location_ok = 1780 topdown ? hint <= orig_hint 1781 : hint >= orig_hint; 1782 1783 #if !(defined(__sh3__) && defined(DIAGNOSTIC)) /* XXXRO: kern/51254 */ 1784 #define UVM_FINDSPACE_KASSERTMSG KASSERTMSG 1785 1786 #else /* sh3 && DIAGNOSTIC */ 1787 /* like KASSERTMSG but make it not fatal */ 1788 #define UVM_FINDSPACE_KASSERTMSG(e, msg, ...) \ 1789 (__predict_true((e)) ? (void)0 : \ 1790 printf(__KASSERTSTR msg "\n", \ 1791 "weak diagnostic ", #e, \ 1792 __FILE__, __LINE__, ## __VA_ARGS__)) 1793 #endif 1794 1795 UVM_FINDSPACE_KASSERTMSG(hint_location_ok, 1796 "%s map=%p hint=%#" PRIxVADDR " %s orig_hint=%#" PRIxVADDR 1797 " length=%#" PRIxVSIZE " uobj=%p uoffset=%#llx align=%" PRIxVSIZE 1798 " flags=%#x entry=%p (uvm_map_findspace line %d)", 1799 topdown ? "topdown" : "bottomup", 1800 map, hint, topdown ? ">" : "<", orig_hint, 1801 length, uobj, (unsigned long long)uoffset, align, 1802 flags, entry, line); 1803 } 1804 1805 /* 1806 * uvm_map_findspace: find "length" sized space in "map". 1807 * 1808 * => "hint" is a hint about where we want it, unless UVM_FLAG_FIXED is 1809 * set in "flags" (in which case we insist on using "hint"). 1810 * => "result" is VA returned 1811 * => uobj/uoffset are to be used to handle VAC alignment, if required 1812 * => if "align" is non-zero, we attempt to align to that value. 1813 * => caller must at least have read-locked map 1814 * => returns NULL on failure, or pointer to prev. map entry if success 1815 * => note this is a cross between the old vm_map_findspace and vm_map_find 1816 */ 1817 1818 struct vm_map_entry * 1819 uvm_map_findspace(struct vm_map *map, vaddr_t hint, vsize_t length, 1820 vaddr_t *result /* OUT */, struct uvm_object *uobj, voff_t uoffset, 1821 vsize_t align, int flags) 1822 { 1823 #define INVARIANTS() \ 1824 uvm_findspace_invariants(map, orig_hint, length, uobj, uoffset, align,\ 1825 flags, hint, entry, __LINE__) 1826 struct vm_map_entry *entry = NULL; 1827 struct vm_map_entry *child, *prev, *tmp; 1828 vaddr_t orig_hint __diagused; 1829 const int topdown = map->flags & VM_MAP_TOPDOWN; 1830 int avail; 1831 UVMHIST_FUNC(__func__); 1832 UVMHIST_CALLARGS(maphist, "(map=%#jx, hint=%#jx, len=%ju, flags=%#jx...", 1833 (uintptr_t)map, hint, length, flags); 1834 UVMHIST_LOG(maphist, " uobj=%#jx, uoffset=%#jx, align=%#jx)", 1835 (uintptr_t)uobj, uoffset, align, 0); 1836 1837 KASSERT((flags & UVM_FLAG_COLORMATCH) != 0 || powerof2(align)); 1838 KASSERT((flags & UVM_FLAG_COLORMATCH) == 0 || align < uvmexp.ncolors); 1839 KASSERT((flags & UVM_FLAG_FIXED) == 0 || align == 0); 1840 1841 uvm_map_check(map, "map_findspace entry"); 1842 1843 /* 1844 * Clamp the hint to the VM map's min/max address, and remmeber 1845 * the clamped original hint. Remember the original hint, 1846 * clamped to the min/max address. If we are aligning, then we 1847 * may have to try again with no alignment constraint if we 1848 * fail the first time. 1849 * 1850 * We use the original hint to verify later that the search has 1851 * been monotonic -- that is, nonincreasing or nondecreasing, 1852 * according to topdown or !topdown respectively. But the 1853 * clamping is not monotonic. 1854 */ 1855 if (hint < vm_map_min(map)) { /* check ranges ... */ 1856 if (flags & UVM_FLAG_FIXED) { 1857 UVMHIST_LOG(maphist,"<- VA below map range",0,0,0,0); 1858 return (NULL); 1859 } 1860 hint = vm_map_min(map); 1861 } 1862 if (hint > vm_map_max(map)) { 1863 UVMHIST_LOG(maphist,"<- VA %#jx > range [%#jx->%#jx]", 1864 hint, vm_map_min(map), vm_map_max(map), 0); 1865 return (NULL); 1866 } 1867 orig_hint = hint; 1868 INVARIANTS(); 1869 1870 UVMHIST_LOG(maphist,"<- VA %#jx vs range [%#jx->%#jx]", 1871 hint, vm_map_min(map), vm_map_max(map), 0); 1872 1873 /* 1874 * hint may not be aligned properly; we need round up or down it 1875 * before proceeding further. 1876 */ 1877 if ((flags & UVM_FLAG_COLORMATCH) == 0) { 1878 uvm_map_align_va(&hint, align, topdown); 1879 INVARIANTS(); 1880 } 1881 1882 UVMHIST_LOG(maphist,"<- VA %#jx vs range [%#jx->%#jx]", 1883 hint, vm_map_min(map), vm_map_max(map), 0); 1884 /* 1885 * Look for the first possible address; if there's already 1886 * something at this address, we have to start after it. 1887 */ 1888 1889 /* 1890 * @@@: there are four, no, eight cases to consider. 1891 * 1892 * 0: found, fixed, bottom up -> fail 1893 * 1: found, fixed, top down -> fail 1894 * 2: found, not fixed, bottom up -> start after entry->end, 1895 * loop up 1896 * 3: found, not fixed, top down -> start before entry->start, 1897 * loop down 1898 * 4: not found, fixed, bottom up -> check entry->next->start, fail 1899 * 5: not found, fixed, top down -> check entry->next->start, fail 1900 * 6: not found, not fixed, bottom up -> check entry->next->start, 1901 * loop up 1902 * 7: not found, not fixed, top down -> check entry->next->start, 1903 * loop down 1904 * 1905 * as you can see, it reduces to roughly five cases, and that 1906 * adding top down mapping only adds one unique case (without 1907 * it, there would be four cases). 1908 */ 1909 1910 if ((flags & UVM_FLAG_FIXED) == 0 && 1911 hint == (topdown ? vm_map_max(map) : vm_map_min(map))) { 1912 /* 1913 * The uvm_map_findspace algorithm is monotonic -- for 1914 * topdown VM it starts with a high hint and returns a 1915 * lower free address; for !topdown VM it starts with a 1916 * low hint and returns a higher free address. As an 1917 * optimization, start with the first (highest for 1918 * topdown, lowest for !topdown) free address. 1919 * 1920 * XXX This `optimization' probably doesn't actually do 1921 * much in practice unless userland explicitly passes 1922 * the VM map's minimum or maximum address, which 1923 * varies from machine to machine (VM_MAX/MIN_ADDRESS, 1924 * e.g. 0x7fbfdfeff000 on amd64 but 0xfffffffff000 on 1925 * aarch64) and may vary according to other factors 1926 * like sysctl vm.user_va0_disable. In particular, if 1927 * the user specifies 0 as a hint to mmap, then mmap 1928 * will choose a default address which is usually _not_ 1929 * VM_MAX/MIN_ADDRESS but something else instead like 1930 * VM_MAX_ADDRESS - stack size - guard page overhead, 1931 * in which case this branch is never hit. 1932 * 1933 * In fact, this branch appears to have been broken for 1934 * two decades between when topdown was introduced in 1935 * ~2003 and when it was adapted to handle the topdown 1936 * case without violating the monotonicity assertion in 1937 * 2022. Maybe Someone^TM should either ditch the 1938 * optimization or find a better way to do it. 1939 */ 1940 entry = map->first_free; 1941 } else { 1942 if (uvm_map_lookup_entry(map, hint, &entry)) { 1943 /* "hint" address already in use ... */ 1944 if (flags & UVM_FLAG_FIXED) { 1945 UVMHIST_LOG(maphist, "<- fixed & VA in use", 1946 0, 0, 0, 0); 1947 return (NULL); 1948 } 1949 if (topdown) 1950 /* Start from lower gap. */ 1951 entry = entry->prev; 1952 } else if (flags & UVM_FLAG_FIXED) { 1953 if (entry->next->start >= hint + length && 1954 hint + length > hint) 1955 goto found; 1956 1957 /* "hint" address is gap but too small */ 1958 UVMHIST_LOG(maphist, "<- fixed mapping failed", 1959 0, 0, 0, 0); 1960 return (NULL); /* only one shot at it ... */ 1961 } else { 1962 /* 1963 * See if given hint fits in this gap. 1964 */ 1965 avail = uvm_map_space_avail(&hint, length, 1966 uoffset, align, flags, topdown, entry); 1967 INVARIANTS(); 1968 switch (avail) { 1969 case 1: 1970 goto found; 1971 case -1: 1972 goto wraparound; 1973 } 1974 1975 if (topdown) { 1976 /* 1977 * Still there is a chance to fit 1978 * if hint > entry->end. 1979 */ 1980 } else { 1981 /* Start from higher gap. */ 1982 entry = entry->next; 1983 if (entry == &map->header) 1984 goto notfound; 1985 goto nextgap; 1986 } 1987 } 1988 } 1989 1990 /* 1991 * Note that all UVM_FLAGS_FIXED case is already handled. 1992 */ 1993 KDASSERT((flags & UVM_FLAG_FIXED) == 0); 1994 1995 /* Try to find the space in the red-black tree */ 1996 1997 /* Check slot before any entry */ 1998 if (topdown) { 1999 KASSERTMSG(entry->next->start >= vm_map_min(map), 2000 "map=%p entry=%p entry->next=%p" 2001 " entry->next->start=0x%"PRIxVADDR" min=0x%"PRIxVADDR, 2002 map, entry, entry->next, 2003 entry->next->start, vm_map_min(map)); 2004 if (length > entry->next->start - vm_map_min(map)) 2005 hint = vm_map_min(map); /* XXX goto wraparound? */ 2006 else 2007 hint = entry->next->start - length; 2008 KASSERT(hint >= vm_map_min(map)); 2009 } else { 2010 hint = entry->end; 2011 } 2012 INVARIANTS(); 2013 avail = uvm_map_space_avail(&hint, length, uoffset, align, flags, 2014 topdown, entry); 2015 INVARIANTS(); 2016 switch (avail) { 2017 case 1: 2018 goto found; 2019 case -1: 2020 goto wraparound; 2021 } 2022 2023 nextgap: 2024 KDASSERT((flags & UVM_FLAG_FIXED) == 0); 2025 /* If there is not enough space in the whole tree, we fail */ 2026 tmp = ROOT_ENTRY(map); 2027 if (tmp == NULL || tmp->maxgap < length) 2028 goto notfound; 2029 2030 prev = NULL; /* previous candidate */ 2031 2032 /* Find an entry close to hint that has enough space */ 2033 for (; tmp;) { 2034 KASSERT(tmp->next->start == tmp->end + tmp->gap); 2035 if (topdown) { 2036 if (tmp->next->start < hint + length && 2037 (prev == NULL || tmp->end > prev->end)) { 2038 if (tmp->gap >= length) 2039 prev = tmp; 2040 else if ((child = LEFT_ENTRY(tmp)) != NULL 2041 && child->maxgap >= length) 2042 prev = tmp; 2043 } 2044 } else { 2045 if (tmp->end >= hint && 2046 (prev == NULL || tmp->end < prev->end)) { 2047 if (tmp->gap >= length) 2048 prev = tmp; 2049 else if ((child = RIGHT_ENTRY(tmp)) != NULL 2050 && child->maxgap >= length) 2051 prev = tmp; 2052 } 2053 } 2054 if (tmp->next->start < hint + length) 2055 child = RIGHT_ENTRY(tmp); 2056 else if (tmp->end > hint) 2057 child = LEFT_ENTRY(tmp); 2058 else { 2059 if (tmp->gap >= length) 2060 break; 2061 if (topdown) 2062 child = LEFT_ENTRY(tmp); 2063 else 2064 child = RIGHT_ENTRY(tmp); 2065 } 2066 if (child == NULL || child->maxgap < length) 2067 break; 2068 tmp = child; 2069 } 2070 2071 if (tmp != NULL && tmp->start < hint && hint < tmp->next->start) { 2072 /* 2073 * Check if the entry that we found satifies the 2074 * space requirement 2075 */ 2076 if (topdown) { 2077 if (hint > tmp->next->start - length) 2078 hint = tmp->next->start - length; 2079 } else { 2080 if (hint < tmp->end) 2081 hint = tmp->end; 2082 } 2083 INVARIANTS(); 2084 avail = uvm_map_space_avail(&hint, length, uoffset, align, 2085 flags, topdown, tmp); 2086 INVARIANTS(); 2087 switch (avail) { 2088 case 1: 2089 entry = tmp; 2090 goto found; 2091 case -1: 2092 goto wraparound; 2093 } 2094 if (tmp->gap >= length) 2095 goto listsearch; 2096 } 2097 if (prev == NULL) 2098 goto notfound; 2099 2100 if (topdown) { 2101 KASSERT(orig_hint >= prev->next->start - length || 2102 prev->next->start - length > prev->next->start); 2103 hint = prev->next->start - length; 2104 } else { 2105 KASSERT(orig_hint <= prev->end); 2106 hint = prev->end; 2107 } 2108 INVARIANTS(); 2109 avail = uvm_map_space_avail(&hint, length, uoffset, align, 2110 flags, topdown, prev); 2111 INVARIANTS(); 2112 switch (avail) { 2113 case 1: 2114 entry = prev; 2115 goto found; 2116 case -1: 2117 goto wraparound; 2118 } 2119 if (prev->gap >= length) 2120 goto listsearch; 2121 2122 if (topdown) 2123 tmp = LEFT_ENTRY(prev); 2124 else 2125 tmp = RIGHT_ENTRY(prev); 2126 for (;;) { 2127 KASSERT(tmp); 2128 KASSERTMSG(tmp->maxgap >= length, 2129 "tmp->maxgap=0x%"PRIxVSIZE" length=0x%"PRIxVSIZE, 2130 tmp->maxgap, length); 2131 if (topdown) 2132 child = RIGHT_ENTRY(tmp); 2133 else 2134 child = LEFT_ENTRY(tmp); 2135 if (child && child->maxgap >= length) { 2136 tmp = child; 2137 continue; 2138 } 2139 if (tmp->gap >= length) 2140 break; 2141 if (topdown) 2142 tmp = LEFT_ENTRY(tmp); 2143 else 2144 tmp = RIGHT_ENTRY(tmp); 2145 } 2146 2147 if (topdown) { 2148 KASSERT(orig_hint >= tmp->next->start - length || 2149 tmp->next->start - length > tmp->next->start); 2150 hint = tmp->next->start - length; 2151 } else { 2152 KASSERT(orig_hint <= tmp->end); 2153 hint = tmp->end; 2154 } 2155 INVARIANTS(); 2156 avail = uvm_map_space_avail(&hint, length, uoffset, align, 2157 flags, topdown, tmp); 2158 INVARIANTS(); 2159 switch (avail) { 2160 case 1: 2161 entry = tmp; 2162 goto found; 2163 case -1: 2164 goto wraparound; 2165 } 2166 2167 /* 2168 * The tree fails to find an entry because of offset or alignment 2169 * restrictions. Search the list instead. 2170 */ 2171 listsearch: 2172 /* 2173 * Look through the rest of the map, trying to fit a new region in 2174 * the gap between existing regions, or after the very last region. 2175 * note: entry->end = base VA of current gap, 2176 * entry->next->start = VA of end of current gap 2177 */ 2178 2179 INVARIANTS(); 2180 for (;;) { 2181 /* Update hint for current gap. */ 2182 hint = topdown ? entry->next->start - length : entry->end; 2183 INVARIANTS(); 2184 2185 /* See if it fits. */ 2186 avail = uvm_map_space_avail(&hint, length, uoffset, align, 2187 flags, topdown, entry); 2188 INVARIANTS(); 2189 switch (avail) { 2190 case 1: 2191 goto found; 2192 case -1: 2193 goto wraparound; 2194 } 2195 2196 /* Advance to next/previous gap */ 2197 if (topdown) { 2198 if (entry == &map->header) { 2199 UVMHIST_LOG(maphist, "<- failed (off start)", 2200 0,0,0,0); 2201 goto notfound; 2202 } 2203 entry = entry->prev; 2204 } else { 2205 entry = entry->next; 2206 if (entry == &map->header) { 2207 UVMHIST_LOG(maphist, "<- failed (off end)", 2208 0,0,0,0); 2209 goto notfound; 2210 } 2211 } 2212 } 2213 2214 found: 2215 SAVE_HINT(map, map->hint, entry); 2216 *result = hint; 2217 UVMHIST_LOG(maphist,"<- got it! (result=%#jx)", hint, 0,0,0); 2218 INVARIANTS(); 2219 KASSERT(entry->end <= hint); 2220 KASSERT(hint + length <= entry->next->start); 2221 return (entry); 2222 2223 wraparound: 2224 UVMHIST_LOG(maphist, "<- failed (wrap around)", 0,0,0,0); 2225 2226 return (NULL); 2227 2228 notfound: 2229 UVMHIST_LOG(maphist, "<- failed (notfound)", 0,0,0,0); 2230 2231 return (NULL); 2232 #undef INVARIANTS 2233 } 2234 2235 /* 2236 * U N M A P - m a i n h e l p e r f u n c t i o n s 2237 */ 2238 2239 /* 2240 * uvm_unmap_remove: remove mappings from a vm_map (from "start" up to "stop") 2241 * 2242 * => caller must check alignment and size 2243 * => map must be locked by caller 2244 * => we return a list of map entries that we've remove from the map 2245 * in "entry_list" 2246 */ 2247 2248 void 2249 uvm_unmap_remove(struct vm_map *map, vaddr_t start, vaddr_t end, 2250 struct vm_map_entry **entry_list /* OUT */, int flags) 2251 { 2252 struct vm_map_entry *entry, *first_entry, *next; 2253 vaddr_t len; 2254 UVMHIST_FUNC(__func__); 2255 UVMHIST_CALLARGS(maphist,"(map=%#jx, start=%#jx, end=%#jx)", 2256 (uintptr_t)map, start, end, 0); 2257 VM_MAP_RANGE_CHECK(map, start, end); 2258 2259 uvm_map_check(map, "unmap_remove entry"); 2260 2261 /* 2262 * find first entry 2263 */ 2264 2265 if (uvm_map_lookup_entry(map, start, &first_entry) == true) { 2266 /* clip and go... */ 2267 entry = first_entry; 2268 UVM_MAP_CLIP_START(map, entry, start); 2269 /* critical! prevents stale hint */ 2270 SAVE_HINT(map, entry, entry->prev); 2271 } else { 2272 entry = first_entry->next; 2273 } 2274 2275 /* 2276 * save the free space hint 2277 */ 2278 2279 if (map->first_free != &map->header && map->first_free->start >= start) 2280 map->first_free = entry->prev; 2281 2282 /* 2283 * note: we now re-use first_entry for a different task. we remove 2284 * a number of map entries from the map and save them in a linked 2285 * list headed by "first_entry". once we remove them from the map 2286 * the caller should unlock the map and drop the references to the 2287 * backing objects [c.f. uvm_unmap_detach]. the object is to 2288 * separate unmapping from reference dropping. why? 2289 * [1] the map has to be locked for unmapping 2290 * [2] the map need not be locked for reference dropping 2291 * [3] dropping references may trigger pager I/O, and if we hit 2292 * a pager that does synchronous I/O we may have to wait for it. 2293 * [4] we would like all waiting for I/O to occur with maps unlocked 2294 * so that we don't block other threads. 2295 */ 2296 2297 first_entry = NULL; 2298 *entry_list = NULL; 2299 2300 /* 2301 * break up the area into map entry sized regions and unmap. note 2302 * that all mappings have to be removed before we can even consider 2303 * dropping references to amaps or VM objects (otherwise we could end 2304 * up with a mapping to a page on the free list which would be very bad) 2305 */ 2306 2307 while ((entry != &map->header) && (entry->start < end)) { 2308 KASSERT((entry->flags & UVM_MAP_STATIC) == 0); 2309 2310 UVM_MAP_CLIP_END(map, entry, end); 2311 next = entry->next; 2312 len = entry->end - entry->start; 2313 2314 /* 2315 * unwire before removing addresses from the pmap; otherwise 2316 * unwiring will put the entries back into the pmap (XXX). 2317 */ 2318 2319 if (VM_MAPENT_ISWIRED(entry)) { 2320 uvm_map_entry_unwire(map, entry); 2321 } 2322 if (flags & UVM_FLAG_VAONLY) { 2323 2324 /* nothing */ 2325 2326 } else if ((map->flags & VM_MAP_PAGEABLE) == 0) { 2327 2328 /* 2329 * if the map is non-pageable, any pages mapped there 2330 * must be wired and entered with pmap_kenter_pa(), 2331 * and we should free any such pages immediately. 2332 * this is mostly used for kmem_map. 2333 */ 2334 KASSERT(vm_map_pmap(map) == pmap_kernel()); 2335 2336 uvm_km_pgremove_intrsafe(map, entry->start, entry->end); 2337 } else if (UVM_ET_ISOBJ(entry) && 2338 UVM_OBJ_IS_KERN_OBJECT(entry->object.uvm_obj)) { 2339 panic("%s: kernel object %p %p\n", 2340 __func__, map, entry); 2341 } else if (UVM_ET_ISOBJ(entry) || entry->aref.ar_amap) { 2342 /* 2343 * remove mappings the standard way. lock object 2344 * and/or amap to ensure vm_page state does not 2345 * change while in pmap_remove(). 2346 */ 2347 2348 #ifdef __HAVE_UNLOCKED_PMAP /* XXX temporary */ 2349 uvm_map_lock_entry(entry, RW_WRITER); 2350 #else 2351 uvm_map_lock_entry(entry, RW_READER); 2352 #endif 2353 pmap_remove(map->pmap, entry->start, entry->end); 2354 2355 /* 2356 * note: if map is dying, leave pmap_update() for 2357 * later. if the map is to be reused (exec) then 2358 * pmap_update() will be called. if the map is 2359 * being disposed of (exit) then pmap_destroy() 2360 * will be called. 2361 */ 2362 2363 if ((map->flags & VM_MAP_DYING) == 0) { 2364 pmap_update(vm_map_pmap(map)); 2365 } else { 2366 KASSERT(vm_map_pmap(map) != pmap_kernel()); 2367 } 2368 2369 uvm_map_unlock_entry(entry); 2370 } 2371 2372 #if defined(UVMDEBUG) 2373 /* 2374 * check if there's remaining mapping, 2375 * which is a bug in caller. 2376 */ 2377 2378 vaddr_t va; 2379 for (va = entry->start; va < entry->end; 2380 va += PAGE_SIZE) { 2381 if (pmap_extract(vm_map_pmap(map), va, NULL)) { 2382 panic("%s: %#"PRIxVADDR" has mapping", 2383 __func__, va); 2384 } 2385 } 2386 2387 if (VM_MAP_IS_KERNEL(map) && (flags & UVM_FLAG_NOWAIT) == 0) { 2388 uvm_km_check_empty(map, entry->start, entry->end); 2389 } 2390 #endif /* defined(UVMDEBUG) */ 2391 2392 /* 2393 * remove entry from map and put it on our list of entries 2394 * that we've nuked. then go to next entry. 2395 */ 2396 2397 UVMHIST_LOG(maphist, " removed map entry %#jx", 2398 (uintptr_t)entry, 0, 0, 0); 2399 2400 /* critical! prevents stale hint */ 2401 SAVE_HINT(map, entry, entry->prev); 2402 2403 uvm_map_entry_unlink(map, entry); 2404 KASSERT(map->size >= len); 2405 map->size -= len; 2406 entry->prev = NULL; 2407 entry->next = first_entry; 2408 first_entry = entry; 2409 entry = next; 2410 } 2411 2412 uvm_map_check(map, "unmap_remove leave"); 2413 2414 /* 2415 * now we've cleaned up the map and are ready for the caller to drop 2416 * references to the mapped objects. 2417 */ 2418 2419 *entry_list = first_entry; 2420 UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0); 2421 2422 if (map->flags & VM_MAP_WANTVA) { 2423 mutex_enter(&map->misc_lock); 2424 map->flags &= ~VM_MAP_WANTVA; 2425 cv_broadcast(&map->cv); 2426 mutex_exit(&map->misc_lock); 2427 } 2428 } 2429 2430 /* 2431 * uvm_unmap_detach: drop references in a chain of map entries 2432 * 2433 * => we will free the map entries as we traverse the list. 2434 */ 2435 2436 void 2437 uvm_unmap_detach(struct vm_map_entry *first_entry, int flags) 2438 { 2439 struct vm_map_entry *next_entry; 2440 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 2441 2442 while (first_entry) { 2443 KASSERT(!VM_MAPENT_ISWIRED(first_entry)); 2444 UVMHIST_LOG(maphist, 2445 " detach %#jx: amap=%#jx, obj=%#jx, submap?=%jd", 2446 (uintptr_t)first_entry, 2447 (uintptr_t)first_entry->aref.ar_amap, 2448 (uintptr_t)first_entry->object.uvm_obj, 2449 UVM_ET_ISSUBMAP(first_entry)); 2450 2451 /* 2452 * drop reference to amap, if we've got one 2453 */ 2454 2455 if (first_entry->aref.ar_amap) 2456 uvm_map_unreference_amap(first_entry, flags); 2457 2458 /* 2459 * drop reference to our backing object, if we've got one 2460 */ 2461 2462 KASSERT(!UVM_ET_ISSUBMAP(first_entry)); 2463 if (UVM_ET_ISOBJ(first_entry) && 2464 first_entry->object.uvm_obj->pgops->pgo_detach) { 2465 (*first_entry->object.uvm_obj->pgops->pgo_detach) 2466 (first_entry->object.uvm_obj); 2467 } 2468 next_entry = first_entry->next; 2469 uvm_mapent_free(first_entry); 2470 first_entry = next_entry; 2471 } 2472 UVMHIST_LOG(maphist, "<- done", 0,0,0,0); 2473 } 2474 2475 /* 2476 * E X T R A C T I O N F U N C T I O N S 2477 */ 2478 2479 /* 2480 * uvm_map_reserve: reserve space in a vm_map for future use. 2481 * 2482 * => we reserve space in a map by putting a dummy map entry in the 2483 * map (dummy means obj=NULL, amap=NULL, prot=VM_PROT_NONE) 2484 * => map should be unlocked (we will write lock it) 2485 * => we return true if we were able to reserve space 2486 * => XXXCDC: should be inline? 2487 */ 2488 2489 int 2490 uvm_map_reserve(struct vm_map *map, vsize_t size, 2491 vaddr_t offset /* hint for pmap_prefer */, 2492 vsize_t align /* alignment */, 2493 vaddr_t *raddr /* IN:hint, OUT: reserved VA */, 2494 uvm_flag_t flags /* UVM_FLAG_FIXED or UVM_FLAG_COLORMATCH or 0 */) 2495 { 2496 UVMHIST_FUNC(__func__); 2497 UVMHIST_CALLARGS(maphist, "(map=%#jx, size=%#jx, offset=%#jx, addr=%#jx)", 2498 (uintptr_t)map, size, offset, (uintptr_t)raddr); 2499 2500 size = round_page(size); 2501 2502 /* 2503 * reserve some virtual space. 2504 */ 2505 2506 if (uvm_map(map, raddr, size, NULL, offset, align, 2507 UVM_MAPFLAG(UVM_PROT_NONE, UVM_PROT_NONE, UVM_INH_NONE, 2508 UVM_ADV_RANDOM, UVM_FLAG_NOMERGE|flags)) != 0) { 2509 UVMHIST_LOG(maphist, "<- done (no VM)", 0,0,0,0); 2510 return (false); 2511 } 2512 2513 UVMHIST_LOG(maphist, "<- done (*raddr=%#jx)", *raddr,0,0,0); 2514 return (true); 2515 } 2516 2517 /* 2518 * uvm_map_replace: replace a reserved (blank) area of memory with 2519 * real mappings. 2520 * 2521 * => caller must WRITE-LOCK the map 2522 * => we return true if replacement was a success 2523 * => we expect the newents chain to have nnewents entrys on it and 2524 * we expect newents->prev to point to the last entry on the list 2525 * => note newents is allowed to be NULL 2526 */ 2527 2528 static int 2529 uvm_map_replace(struct vm_map *map, vaddr_t start, vaddr_t end, 2530 struct vm_map_entry *newents, int nnewents, vsize_t nsize, 2531 struct vm_map_entry **oldentryp) 2532 { 2533 struct vm_map_entry *oldent, *last; 2534 2535 uvm_map_check(map, "map_replace entry"); 2536 2537 /* 2538 * first find the blank map entry at the specified address 2539 */ 2540 2541 if (!uvm_map_lookup_entry(map, start, &oldent)) { 2542 return (false); 2543 } 2544 2545 /* 2546 * check to make sure we have a proper blank entry 2547 */ 2548 2549 if (end < oldent->end) { 2550 UVM_MAP_CLIP_END(map, oldent, end); 2551 } 2552 if (oldent->start != start || oldent->end != end || 2553 oldent->object.uvm_obj != NULL || oldent->aref.ar_amap != NULL) { 2554 return (false); 2555 } 2556 2557 #ifdef DIAGNOSTIC 2558 2559 /* 2560 * sanity check the newents chain 2561 */ 2562 2563 { 2564 struct vm_map_entry *tmpent = newents; 2565 int nent = 0; 2566 vsize_t sz = 0; 2567 vaddr_t cur = start; 2568 2569 while (tmpent) { 2570 nent++; 2571 sz += tmpent->end - tmpent->start; 2572 if (tmpent->start < cur) 2573 panic("uvm_map_replace1"); 2574 if (tmpent->start >= tmpent->end || tmpent->end > end) { 2575 panic("uvm_map_replace2: " 2576 "tmpent->start=%#"PRIxVADDR 2577 ", tmpent->end=%#"PRIxVADDR 2578 ", end=%#"PRIxVADDR, 2579 tmpent->start, tmpent->end, end); 2580 } 2581 cur = tmpent->end; 2582 if (tmpent->next) { 2583 if (tmpent->next->prev != tmpent) 2584 panic("uvm_map_replace3"); 2585 } else { 2586 if (newents->prev != tmpent) 2587 panic("uvm_map_replace4"); 2588 } 2589 tmpent = tmpent->next; 2590 } 2591 if (nent != nnewents) 2592 panic("uvm_map_replace5"); 2593 if (sz != nsize) 2594 panic("uvm_map_replace6"); 2595 } 2596 #endif 2597 2598 /* 2599 * map entry is a valid blank! replace it. (this does all the 2600 * work of map entry link/unlink...). 2601 */ 2602 2603 if (newents) { 2604 last = newents->prev; 2605 2606 /* critical: flush stale hints out of map */ 2607 SAVE_HINT(map, map->hint, newents); 2608 if (map->first_free == oldent) 2609 map->first_free = last; 2610 2611 last->next = oldent->next; 2612 last->next->prev = last; 2613 2614 /* Fix RB tree */ 2615 uvm_rb_remove(map, oldent); 2616 2617 newents->prev = oldent->prev; 2618 newents->prev->next = newents; 2619 map->nentries = map->nentries + (nnewents - 1); 2620 2621 /* Fixup the RB tree */ 2622 { 2623 int i; 2624 struct vm_map_entry *tmp; 2625 2626 tmp = newents; 2627 for (i = 0; i < nnewents && tmp; i++) { 2628 uvm_rb_insert(map, tmp); 2629 tmp = tmp->next; 2630 } 2631 } 2632 } else { 2633 /* NULL list of new entries: just remove the old one */ 2634 clear_hints(map, oldent); 2635 uvm_map_entry_unlink(map, oldent); 2636 } 2637 map->size -= end - start - nsize; 2638 2639 uvm_map_check(map, "map_replace leave"); 2640 2641 /* 2642 * now we can free the old blank entry and return. 2643 */ 2644 2645 *oldentryp = oldent; 2646 return (true); 2647 } 2648 2649 /* 2650 * uvm_map_extract: extract a mapping from a map and put it somewhere 2651 * (maybe removing the old mapping) 2652 * 2653 * => maps should be unlocked (we will write lock them) 2654 * => returns 0 on success, error code otherwise 2655 * => start must be page aligned 2656 * => len must be page sized 2657 * => flags: 2658 * UVM_EXTRACT_REMOVE: remove mappings from srcmap 2659 * UVM_EXTRACT_CONTIG: abort if unmapped area (advisory only) 2660 * UVM_EXTRACT_QREF: for a temporary extraction do quick obj refs 2661 * UVM_EXTRACT_FIXPROT: set prot to maxprot as we go 2662 * UVM_EXTRACT_PROT_ALL: set prot to UVM_PROT_ALL as we go 2663 * >>>NOTE: if you set REMOVE, you are not allowed to use CONTIG or QREF!<<< 2664 * >>>NOTE: QREF's must be unmapped via the QREF path, thus should only 2665 * be used from within the kernel in a kernel level map <<< 2666 */ 2667 2668 int 2669 uvm_map_extract(struct vm_map *srcmap, vaddr_t start, vsize_t len, 2670 struct vm_map *dstmap, vaddr_t *dstaddrp, int flags) 2671 { 2672 vaddr_t dstaddr, end, newend, oldoffset, fudge, orig_fudge; 2673 struct vm_map_entry *chain, *endchain, *entry, *orig_entry, *newentry, 2674 *deadentry, *oldentry; 2675 struct vm_map_entry *resentry = NULL; /* a dummy reservation entry */ 2676 vsize_t elen __unused; 2677 int nchain, error, copy_ok; 2678 vsize_t nsize; 2679 UVMHIST_FUNC(__func__); 2680 UVMHIST_CALLARGS(maphist,"(srcmap=%#jx,start=%#jx, len=%#jx", 2681 (uintptr_t)srcmap, start, len, 0); 2682 UVMHIST_LOG(maphist," ...,dstmap=%#jx, flags=%#jx)", 2683 (uintptr_t)dstmap, flags, 0, 0); 2684 2685 /* 2686 * step 0: sanity check: start must be on a page boundary, length 2687 * must be page sized. can't ask for CONTIG/QREF if you asked for 2688 * REMOVE. 2689 */ 2690 2691 KASSERTMSG((start & PAGE_MASK) == 0, "start=0x%"PRIxVADDR, start); 2692 KASSERTMSG((len & PAGE_MASK) == 0, "len=0x%"PRIxVADDR, len); 2693 KASSERT((flags & UVM_EXTRACT_REMOVE) == 0 || 2694 (flags & (UVM_EXTRACT_CONTIG|UVM_EXTRACT_QREF)) == 0); 2695 2696 /* 2697 * step 1: reserve space in the target map for the extracted area 2698 */ 2699 2700 if ((flags & UVM_EXTRACT_RESERVED) == 0) { 2701 dstaddr = vm_map_min(dstmap); 2702 if (!uvm_map_reserve(dstmap, len, start, 2703 atop(start) & uvmexp.colormask, &dstaddr, 2704 UVM_FLAG_COLORMATCH)) 2705 return (ENOMEM); 2706 KASSERT((atop(start ^ dstaddr) & uvmexp.colormask) == 0); 2707 *dstaddrp = dstaddr; /* pass address back to caller */ 2708 UVMHIST_LOG(maphist, " dstaddr=%#jx", dstaddr,0,0,0); 2709 } else { 2710 dstaddr = *dstaddrp; 2711 } 2712 2713 /* 2714 * step 2: setup for the extraction process loop by init'ing the 2715 * map entry chain, locking src map, and looking up the first useful 2716 * entry in the map. 2717 */ 2718 2719 end = start + len; 2720 newend = dstaddr + len; 2721 chain = endchain = NULL; 2722 nchain = 0; 2723 nsize = 0; 2724 vm_map_lock(srcmap); 2725 2726 if (uvm_map_lookup_entry(srcmap, start, &entry)) { 2727 2728 /* "start" is within an entry */ 2729 if (flags & UVM_EXTRACT_QREF) { 2730 2731 /* 2732 * for quick references we don't clip the entry, so 2733 * the entry may map space "before" the starting 2734 * virtual address... this is the "fudge" factor 2735 * (which can be non-zero only the first time 2736 * through the "while" loop in step 3). 2737 */ 2738 2739 fudge = start - entry->start; 2740 } else { 2741 2742 /* 2743 * normal reference: we clip the map to fit (thus 2744 * fudge is zero) 2745 */ 2746 2747 UVM_MAP_CLIP_START(srcmap, entry, start); 2748 SAVE_HINT(srcmap, srcmap->hint, entry->prev); 2749 fudge = 0; 2750 } 2751 } else { 2752 2753 /* "start" is not within an entry ... skip to next entry */ 2754 if (flags & UVM_EXTRACT_CONTIG) { 2755 error = EINVAL; 2756 goto bad; /* definite hole here ... */ 2757 } 2758 2759 entry = entry->next; 2760 fudge = 0; 2761 } 2762 2763 /* save values from srcmap for step 6 */ 2764 orig_entry = entry; 2765 orig_fudge = fudge; 2766 2767 /* 2768 * step 3: now start looping through the map entries, extracting 2769 * as we go. 2770 */ 2771 2772 while (entry->start < end && entry != &srcmap->header) { 2773 2774 /* if we are not doing a quick reference, clip it */ 2775 if ((flags & UVM_EXTRACT_QREF) == 0) 2776 UVM_MAP_CLIP_END(srcmap, entry, end); 2777 2778 /* clear needs_copy (allow chunking) */ 2779 if (UVM_ET_ISNEEDSCOPY(entry)) { 2780 amap_copy(srcmap, entry, 2781 AMAP_COPY_NOWAIT|AMAP_COPY_NOMERGE, start, end); 2782 if (UVM_ET_ISNEEDSCOPY(entry)) { /* failed? */ 2783 error = ENOMEM; 2784 goto bad; 2785 } 2786 2787 /* amap_copy could clip (during chunk)! update fudge */ 2788 if (fudge) { 2789 fudge = start - entry->start; 2790 orig_fudge = fudge; 2791 } 2792 } 2793 2794 /* calculate the offset of this from "start" */ 2795 oldoffset = (entry->start + fudge) - start; 2796 2797 /* allocate a new map entry */ 2798 newentry = uvm_mapent_alloc(dstmap, 0); 2799 if (newentry == NULL) { 2800 error = ENOMEM; 2801 goto bad; 2802 } 2803 2804 /* set up new map entry */ 2805 newentry->next = NULL; 2806 newentry->prev = endchain; 2807 newentry->start = dstaddr + oldoffset; 2808 newentry->end = 2809 newentry->start + (entry->end - (entry->start + fudge)); 2810 if (newentry->end > newend || newentry->end < newentry->start) 2811 newentry->end = newend; 2812 newentry->object.uvm_obj = entry->object.uvm_obj; 2813 if (newentry->object.uvm_obj) { 2814 if (newentry->object.uvm_obj->pgops->pgo_reference) 2815 newentry->object.uvm_obj->pgops-> 2816 pgo_reference(newentry->object.uvm_obj); 2817 newentry->offset = entry->offset + fudge; 2818 } else { 2819 newentry->offset = 0; 2820 } 2821 newentry->etype = entry->etype; 2822 if (flags & UVM_EXTRACT_PROT_ALL) { 2823 newentry->protection = newentry->max_protection = 2824 UVM_PROT_ALL; 2825 } else { 2826 newentry->protection = (flags & UVM_EXTRACT_FIXPROT) ? 2827 entry->max_protection : entry->protection; 2828 newentry->max_protection = entry->max_protection; 2829 } 2830 newentry->inheritance = entry->inheritance; 2831 newentry->wired_count = 0; 2832 newentry->aref.ar_amap = entry->aref.ar_amap; 2833 if (newentry->aref.ar_amap) { 2834 newentry->aref.ar_pageoff = 2835 entry->aref.ar_pageoff + (fudge >> PAGE_SHIFT); 2836 uvm_map_reference_amap(newentry, AMAP_SHARED | 2837 ((flags & UVM_EXTRACT_QREF) ? AMAP_REFALL : 0)); 2838 } else { 2839 newentry->aref.ar_pageoff = 0; 2840 } 2841 newentry->advice = entry->advice; 2842 if ((flags & UVM_EXTRACT_QREF) != 0) { 2843 newentry->flags |= UVM_MAP_NOMERGE; 2844 } 2845 2846 /* now link it on the chain */ 2847 nchain++; 2848 nsize += newentry->end - newentry->start; 2849 if (endchain == NULL) { 2850 chain = endchain = newentry; 2851 } else { 2852 endchain->next = newentry; 2853 endchain = newentry; 2854 } 2855 2856 /* end of 'while' loop! */ 2857 if ((flags & UVM_EXTRACT_CONTIG) && entry->end < end && 2858 (entry->next == &srcmap->header || 2859 entry->next->start != entry->end)) { 2860 error = EINVAL; 2861 goto bad; 2862 } 2863 entry = entry->next; 2864 fudge = 0; 2865 } 2866 2867 /* 2868 * step 4: close off chain (in format expected by uvm_map_replace) 2869 */ 2870 2871 if (chain) 2872 chain->prev = endchain; 2873 2874 /* 2875 * step 5: attempt to lock the dest map so we can pmap_copy. 2876 * note usage of copy_ok: 2877 * 1 => dstmap locked, pmap_copy ok, and we "replace" here (step 5) 2878 * 0 => dstmap unlocked, NO pmap_copy, and we will "replace" in step 7 2879 */ 2880 2881 if (srcmap == dstmap || vm_map_lock_try(dstmap) == true) { 2882 copy_ok = 1; 2883 if (!uvm_map_replace(dstmap, dstaddr, dstaddr+len, chain, 2884 nchain, nsize, &resentry)) { 2885 if (srcmap != dstmap) 2886 vm_map_unlock(dstmap); 2887 error = EIO; 2888 goto bad; 2889 } 2890 } else { 2891 copy_ok = 0; 2892 /* replace deferred until step 7 */ 2893 } 2894 2895 /* 2896 * step 6: traverse the srcmap a second time to do the following: 2897 * - if we got a lock on the dstmap do pmap_copy 2898 * - if UVM_EXTRACT_REMOVE remove the entries 2899 * we make use of orig_entry and orig_fudge (saved in step 2) 2900 */ 2901 2902 if (copy_ok || (flags & UVM_EXTRACT_REMOVE)) { 2903 2904 /* purge possible stale hints from srcmap */ 2905 if (flags & UVM_EXTRACT_REMOVE) { 2906 SAVE_HINT(srcmap, srcmap->hint, orig_entry->prev); 2907 if (srcmap->first_free != &srcmap->header && 2908 srcmap->first_free->start >= start) 2909 srcmap->first_free = orig_entry->prev; 2910 } 2911 2912 entry = orig_entry; 2913 fudge = orig_fudge; 2914 deadentry = NULL; /* for UVM_EXTRACT_REMOVE */ 2915 2916 while (entry->start < end && entry != &srcmap->header) { 2917 if (copy_ok) { 2918 oldoffset = (entry->start + fudge) - start; 2919 elen = MIN(end, entry->end) - 2920 (entry->start + fudge); 2921 pmap_copy(dstmap->pmap, srcmap->pmap, 2922 dstaddr + oldoffset, elen, 2923 entry->start + fudge); 2924 } 2925 2926 /* we advance "entry" in the following if statement */ 2927 if (flags & UVM_EXTRACT_REMOVE) { 2928 #ifdef __HAVE_UNLOCKED_PMAP /* XXX temporary */ 2929 uvm_map_lock_entry(entry, RW_WRITER); 2930 #else 2931 uvm_map_lock_entry(entry, RW_READER); 2932 #endif 2933 pmap_remove(srcmap->pmap, entry->start, 2934 entry->end); 2935 uvm_map_unlock_entry(entry); 2936 oldentry = entry; /* save entry */ 2937 entry = entry->next; /* advance */ 2938 uvm_map_entry_unlink(srcmap, oldentry); 2939 /* add to dead list */ 2940 oldentry->next = deadentry; 2941 deadentry = oldentry; 2942 } else { 2943 entry = entry->next; /* advance */ 2944 } 2945 2946 /* end of 'while' loop */ 2947 fudge = 0; 2948 } 2949 pmap_update(srcmap->pmap); 2950 2951 /* 2952 * unlock dstmap. we will dispose of deadentry in 2953 * step 7 if needed 2954 */ 2955 2956 if (copy_ok && srcmap != dstmap) 2957 vm_map_unlock(dstmap); 2958 2959 } else { 2960 deadentry = NULL; 2961 } 2962 2963 /* 2964 * step 7: we are done with the source map, unlock. if copy_ok 2965 * is 0 then we have not replaced the dummy mapping in dstmap yet 2966 * and we need to do so now. 2967 */ 2968 2969 vm_map_unlock(srcmap); 2970 if ((flags & UVM_EXTRACT_REMOVE) && deadentry) 2971 uvm_unmap_detach(deadentry, 0); /* dispose of old entries */ 2972 2973 /* now do the replacement if we didn't do it in step 5 */ 2974 if (copy_ok == 0) { 2975 vm_map_lock(dstmap); 2976 error = uvm_map_replace(dstmap, dstaddr, dstaddr+len, chain, 2977 nchain, nsize, &resentry); 2978 vm_map_unlock(dstmap); 2979 2980 if (error == false) { 2981 error = EIO; 2982 goto bad2; 2983 } 2984 } 2985 2986 if (resentry != NULL) 2987 uvm_mapent_free(resentry); 2988 2989 return (0); 2990 2991 /* 2992 * bad: failure recovery 2993 */ 2994 bad: 2995 vm_map_unlock(srcmap); 2996 bad2: /* src already unlocked */ 2997 if (chain) 2998 uvm_unmap_detach(chain, 2999 (flags & UVM_EXTRACT_QREF) ? AMAP_REFALL : 0); 3000 3001 if (resentry != NULL) 3002 uvm_mapent_free(resentry); 3003 3004 if ((flags & UVM_EXTRACT_RESERVED) == 0) { 3005 uvm_unmap(dstmap, dstaddr, dstaddr+len); /* ??? */ 3006 } 3007 return (error); 3008 } 3009 3010 /* end of extraction functions */ 3011 3012 /* 3013 * uvm_map_submap: punch down part of a map into a submap 3014 * 3015 * => only the kernel_map is allowed to be submapped 3016 * => the purpose of submapping is to break up the locking granularity 3017 * of a larger map 3018 * => the range specified must have been mapped previously with a uvm_map() 3019 * call [with uobj==NULL] to create a blank map entry in the main map. 3020 * [And it had better still be blank!] 3021 * => maps which contain submaps should never be copied or forked. 3022 * => to remove a submap, use uvm_unmap() on the main map 3023 * and then uvm_map_deallocate() the submap. 3024 * => main map must be unlocked. 3025 * => submap must have been init'd and have a zero reference count. 3026 * [need not be locked as we don't actually reference it] 3027 */ 3028 3029 int 3030 uvm_map_submap(struct vm_map *map, vaddr_t start, vaddr_t end, 3031 struct vm_map *submap) 3032 { 3033 struct vm_map_entry *entry; 3034 int error; 3035 3036 vm_map_lock(map); 3037 VM_MAP_RANGE_CHECK(map, start, end); 3038 3039 if (uvm_map_lookup_entry(map, start, &entry)) { 3040 UVM_MAP_CLIP_START(map, entry, start); 3041 UVM_MAP_CLIP_END(map, entry, end); /* to be safe */ 3042 } else { 3043 entry = NULL; 3044 } 3045 3046 if (entry != NULL && 3047 entry->start == start && entry->end == end && 3048 entry->object.uvm_obj == NULL && entry->aref.ar_amap == NULL && 3049 !UVM_ET_ISCOPYONWRITE(entry) && !UVM_ET_ISNEEDSCOPY(entry)) { 3050 entry->etype |= UVM_ET_SUBMAP; 3051 entry->object.sub_map = submap; 3052 entry->offset = 0; 3053 uvm_map_reference(submap); 3054 error = 0; 3055 } else { 3056 error = EINVAL; 3057 } 3058 vm_map_unlock(map); 3059 3060 return error; 3061 } 3062 3063 /* 3064 * uvm_map_protect_user: change map protection on behalf of the user. 3065 * Enforces PAX settings as necessary. 3066 */ 3067 int 3068 uvm_map_protect_user(struct lwp *l, vaddr_t start, vaddr_t end, 3069 vm_prot_t new_prot) 3070 { 3071 int error; 3072 3073 if ((error = PAX_MPROTECT_VALIDATE(l, new_prot))) 3074 return error; 3075 3076 return uvm_map_protect(&l->l_proc->p_vmspace->vm_map, start, end, 3077 new_prot, false); 3078 } 3079 3080 3081 /* 3082 * uvm_map_protect: change map protection 3083 * 3084 * => set_max means set max_protection. 3085 * => map must be unlocked. 3086 */ 3087 3088 #define MASK(entry) (UVM_ET_ISCOPYONWRITE(entry) ? \ 3089 ~VM_PROT_WRITE : VM_PROT_ALL) 3090 3091 int 3092 uvm_map_protect(struct vm_map *map, vaddr_t start, vaddr_t end, 3093 vm_prot_t new_prot, bool set_max) 3094 { 3095 struct vm_map_entry *current, *entry; 3096 int error = 0; 3097 UVMHIST_FUNC(__func__); 3098 UVMHIST_CALLARGS(maphist,"(map=%#jx,start=%#jx,end=%#jx,new_prot=%#jx)", 3099 (uintptr_t)map, start, end, new_prot); 3100 3101 vm_map_lock(map); 3102 VM_MAP_RANGE_CHECK(map, start, end); 3103 if (uvm_map_lookup_entry(map, start, &entry)) { 3104 UVM_MAP_CLIP_START(map, entry, start); 3105 } else { 3106 entry = entry->next; 3107 } 3108 3109 /* 3110 * make a first pass to check for protection violations. 3111 */ 3112 3113 current = entry; 3114 while ((current != &map->header) && (current->start < end)) { 3115 if (UVM_ET_ISSUBMAP(current)) { 3116 error = EINVAL; 3117 goto out; 3118 } 3119 if ((new_prot & current->max_protection) != new_prot) { 3120 error = EACCES; 3121 goto out; 3122 } 3123 /* 3124 * Don't allow VM_PROT_EXECUTE to be set on entries that 3125 * point to vnodes that are associated with a NOEXEC file 3126 * system. 3127 */ 3128 if (UVM_ET_ISOBJ(current) && 3129 UVM_OBJ_IS_VNODE(current->object.uvm_obj)) { 3130 struct vnode *vp = 3131 (struct vnode *) current->object.uvm_obj; 3132 3133 if ((new_prot & VM_PROT_EXECUTE) != 0 && 3134 (vp->v_mount->mnt_flag & MNT_NOEXEC) != 0) { 3135 error = EACCES; 3136 goto out; 3137 } 3138 } 3139 3140 current = current->next; 3141 } 3142 3143 /* go back and fix up protections (no need to clip this time). */ 3144 3145 current = entry; 3146 while ((current != &map->header) && (current->start < end)) { 3147 vm_prot_t old_prot; 3148 3149 UVM_MAP_CLIP_END(map, current, end); 3150 old_prot = current->protection; 3151 if (set_max) 3152 current->protection = 3153 (current->max_protection = new_prot) & old_prot; 3154 else 3155 current->protection = new_prot; 3156 3157 /* 3158 * update physical map if necessary. worry about copy-on-write 3159 * here -- CHECK THIS XXX 3160 */ 3161 3162 if (current->protection != old_prot) { 3163 /* update pmap! */ 3164 #ifdef __HAVE_UNLOCKED_PMAP /* XXX temporary */ 3165 uvm_map_lock_entry(current, RW_WRITER); 3166 #else 3167 uvm_map_lock_entry(current, RW_READER); 3168 #endif 3169 pmap_protect(map->pmap, current->start, current->end, 3170 current->protection & MASK(current)); 3171 uvm_map_unlock_entry(current); 3172 3173 /* 3174 * If this entry points at a vnode, and the 3175 * protection includes VM_PROT_EXECUTE, mark 3176 * the vnode as VEXECMAP. 3177 */ 3178 if (UVM_ET_ISOBJ(current)) { 3179 struct uvm_object *uobj = 3180 current->object.uvm_obj; 3181 3182 if (UVM_OBJ_IS_VNODE(uobj) && 3183 (current->protection & VM_PROT_EXECUTE)) { 3184 vn_markexec((struct vnode *) uobj); 3185 } 3186 } 3187 } 3188 3189 /* 3190 * If the map is configured to lock any future mappings, 3191 * wire this entry now if the old protection was VM_PROT_NONE 3192 * and the new protection is not VM_PROT_NONE. 3193 */ 3194 3195 if ((map->flags & VM_MAP_WIREFUTURE) != 0 && 3196 VM_MAPENT_ISWIRED(current) == 0 && 3197 old_prot == VM_PROT_NONE && 3198 new_prot != VM_PROT_NONE) { 3199 3200 /* 3201 * We must call pmap_update() here because the 3202 * pmap_protect() call above might have removed some 3203 * pmap entries and uvm_map_pageable() might create 3204 * some new pmap entries that rely on the prior 3205 * removals being completely finished. 3206 */ 3207 3208 pmap_update(map->pmap); 3209 3210 if (uvm_map_pageable(map, current->start, 3211 current->end, false, 3212 UVM_LK_ENTER|UVM_LK_EXIT) != 0) { 3213 3214 /* 3215 * If locking the entry fails, remember the 3216 * error if it's the first one. Note we 3217 * still continue setting the protection in 3218 * the map, but will return the error 3219 * condition regardless. 3220 * 3221 * XXX Ignore what the actual error is, 3222 * XXX just call it a resource shortage 3223 * XXX so that it doesn't get confused 3224 * XXX what uvm_map_protect() itself would 3225 * XXX normally return. 3226 */ 3227 3228 error = ENOMEM; 3229 } 3230 } 3231 current = current->next; 3232 } 3233 pmap_update(map->pmap); 3234 3235 out: 3236 vm_map_unlock(map); 3237 3238 UVMHIST_LOG(maphist, "<- done, error=%jd",error,0,0,0); 3239 return error; 3240 } 3241 3242 #undef MASK 3243 3244 /* 3245 * uvm_map_inherit: set inheritance code for range of addrs in map. 3246 * 3247 * => map must be unlocked 3248 * => note that the inherit code is used during a "fork". see fork 3249 * code for details. 3250 */ 3251 3252 int 3253 uvm_map_inherit(struct vm_map *map, vaddr_t start, vaddr_t end, 3254 vm_inherit_t new_inheritance) 3255 { 3256 struct vm_map_entry *entry, *temp_entry; 3257 UVMHIST_FUNC(__func__); 3258 UVMHIST_CALLARGS(maphist,"(map=%#jx,start=%#jx,end=%#jx,new_inh=%#jx)", 3259 (uintptr_t)map, start, end, new_inheritance); 3260 3261 switch (new_inheritance) { 3262 case MAP_INHERIT_NONE: 3263 case MAP_INHERIT_COPY: 3264 case MAP_INHERIT_SHARE: 3265 case MAP_INHERIT_ZERO: 3266 break; 3267 default: 3268 UVMHIST_LOG(maphist,"<- done (INVALID ARG)",0,0,0,0); 3269 return EINVAL; 3270 } 3271 3272 vm_map_lock(map); 3273 VM_MAP_RANGE_CHECK(map, start, end); 3274 if (uvm_map_lookup_entry(map, start, &temp_entry)) { 3275 entry = temp_entry; 3276 UVM_MAP_CLIP_START(map, entry, start); 3277 } else { 3278 entry = temp_entry->next; 3279 } 3280 while ((entry != &map->header) && (entry->start < end)) { 3281 UVM_MAP_CLIP_END(map, entry, end); 3282 entry->inheritance = new_inheritance; 3283 entry = entry->next; 3284 } 3285 vm_map_unlock(map); 3286 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 3287 return 0; 3288 } 3289 3290 /* 3291 * uvm_map_advice: set advice code for range of addrs in map. 3292 * 3293 * => map must be unlocked 3294 */ 3295 3296 int 3297 uvm_map_advice(struct vm_map *map, vaddr_t start, vaddr_t end, int new_advice) 3298 { 3299 struct vm_map_entry *entry, *temp_entry; 3300 UVMHIST_FUNC(__func__); 3301 UVMHIST_CALLARGS(maphist,"(map=%#jx,start=%#jx,end=%#jx,new_adv=%#jx)", 3302 (uintptr_t)map, start, end, new_advice); 3303 3304 vm_map_lock(map); 3305 VM_MAP_RANGE_CHECK(map, start, end); 3306 if (uvm_map_lookup_entry(map, start, &temp_entry)) { 3307 entry = temp_entry; 3308 UVM_MAP_CLIP_START(map, entry, start); 3309 } else { 3310 entry = temp_entry->next; 3311 } 3312 3313 /* 3314 * XXXJRT: disallow holes? 3315 */ 3316 3317 while ((entry != &map->header) && (entry->start < end)) { 3318 UVM_MAP_CLIP_END(map, entry, end); 3319 3320 switch (new_advice) { 3321 case MADV_NORMAL: 3322 case MADV_RANDOM: 3323 case MADV_SEQUENTIAL: 3324 /* nothing special here */ 3325 break; 3326 3327 default: 3328 vm_map_unlock(map); 3329 UVMHIST_LOG(maphist,"<- done (INVALID ARG)",0,0,0,0); 3330 return EINVAL; 3331 } 3332 entry->advice = new_advice; 3333 entry = entry->next; 3334 } 3335 3336 vm_map_unlock(map); 3337 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 3338 return 0; 3339 } 3340 3341 /* 3342 * uvm_map_willneed: apply MADV_WILLNEED 3343 */ 3344 3345 int 3346 uvm_map_willneed(struct vm_map *map, vaddr_t start, vaddr_t end) 3347 { 3348 struct vm_map_entry *entry; 3349 UVMHIST_FUNC(__func__); 3350 UVMHIST_CALLARGS(maphist,"(map=%#jx,start=%#jx,end=%#jx)", 3351 (uintptr_t)map, start, end, 0); 3352 3353 vm_map_lock_read(map); 3354 VM_MAP_RANGE_CHECK(map, start, end); 3355 if (!uvm_map_lookup_entry(map, start, &entry)) { 3356 entry = entry->next; 3357 } 3358 while (entry->start < end) { 3359 struct vm_amap * const amap = entry->aref.ar_amap; 3360 struct uvm_object * const uobj = entry->object.uvm_obj; 3361 3362 KASSERT(entry != &map->header); 3363 KASSERT(start < entry->end); 3364 /* 3365 * For now, we handle only the easy but commonly-requested case. 3366 * ie. start prefetching of backing uobj pages. 3367 * 3368 * XXX It might be useful to pmap_enter() the already-in-core 3369 * pages by inventing a "weak" mode for uvm_fault() which would 3370 * only do the PGO_LOCKED pgo_get(). 3371 */ 3372 if (UVM_ET_ISOBJ(entry) && amap == NULL && uobj != NULL) { 3373 off_t offset; 3374 off_t size; 3375 3376 offset = entry->offset; 3377 if (start < entry->start) { 3378 offset += entry->start - start; 3379 } 3380 size = entry->offset + (entry->end - entry->start); 3381 if (entry->end < end) { 3382 size -= end - entry->end; 3383 } 3384 uvm_readahead(uobj, offset, size); 3385 } 3386 entry = entry->next; 3387 } 3388 vm_map_unlock_read(map); 3389 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 3390 return 0; 3391 } 3392 3393 /* 3394 * uvm_map_pageable: sets the pageability of a range in a map. 3395 * 3396 * => wires map entries. should not be used for transient page locking. 3397 * for that, use uvm_fault_wire()/uvm_fault_unwire() (see uvm_vslock()). 3398 * => regions specified as not pageable require lock-down (wired) memory 3399 * and page tables. 3400 * => map must never be read-locked 3401 * => if islocked is true, map is already write-locked 3402 * => we always unlock the map, since we must downgrade to a read-lock 3403 * to call uvm_fault_wire() 3404 * => XXXCDC: check this and try and clean it up. 3405 */ 3406 3407 int 3408 uvm_map_pageable(struct vm_map *map, vaddr_t start, vaddr_t end, 3409 bool new_pageable, int lockflags) 3410 { 3411 struct vm_map_entry *entry, *start_entry, *failed_entry; 3412 int rv; 3413 #ifdef DIAGNOSTIC 3414 u_int timestamp_save; 3415 #endif 3416 UVMHIST_FUNC(__func__); 3417 UVMHIST_CALLARGS(maphist,"(map=%#jx,start=%#jx,end=%#jx,new_pageable=%ju)", 3418 (uintptr_t)map, start, end, new_pageable); 3419 KASSERT(map->flags & VM_MAP_PAGEABLE); 3420 3421 if ((lockflags & UVM_LK_ENTER) == 0) 3422 vm_map_lock(map); 3423 VM_MAP_RANGE_CHECK(map, start, end); 3424 3425 /* 3426 * only one pageability change may take place at one time, since 3427 * uvm_fault_wire assumes it will be called only once for each 3428 * wiring/unwiring. therefore, we have to make sure we're actually 3429 * changing the pageability for the entire region. we do so before 3430 * making any changes. 3431 */ 3432 3433 if (uvm_map_lookup_entry(map, start, &start_entry) == false) { 3434 if ((lockflags & UVM_LK_EXIT) == 0) 3435 vm_map_unlock(map); 3436 3437 UVMHIST_LOG(maphist,"<- done (fault)",0,0,0,0); 3438 return EFAULT; 3439 } 3440 entry = start_entry; 3441 3442 if (start == end) { /* nothing required */ 3443 if ((lockflags & UVM_LK_EXIT) == 0) 3444 vm_map_unlock(map); 3445 3446 UVMHIST_LOG(maphist,"<- done (nothing)",0,0,0,0); 3447 return 0; 3448 } 3449 3450 /* 3451 * handle wiring and unwiring separately. 3452 */ 3453 3454 if (new_pageable) { /* unwire */ 3455 UVM_MAP_CLIP_START(map, entry, start); 3456 3457 /* 3458 * unwiring. first ensure that the range to be unwired is 3459 * really wired down and that there are no holes. 3460 */ 3461 3462 while ((entry != &map->header) && (entry->start < end)) { 3463 if (entry->wired_count == 0 || 3464 (entry->end < end && 3465 (entry->next == &map->header || 3466 entry->next->start > entry->end))) { 3467 if ((lockflags & UVM_LK_EXIT) == 0) 3468 vm_map_unlock(map); 3469 UVMHIST_LOG(maphist, "<- done (INVAL)",0,0,0,0); 3470 return EINVAL; 3471 } 3472 entry = entry->next; 3473 } 3474 3475 /* 3476 * POSIX 1003.1b - a single munlock call unlocks a region, 3477 * regardless of the number of mlock calls made on that 3478 * region. 3479 */ 3480 3481 entry = start_entry; 3482 while ((entry != &map->header) && (entry->start < end)) { 3483 UVM_MAP_CLIP_END(map, entry, end); 3484 if (VM_MAPENT_ISWIRED(entry)) 3485 uvm_map_entry_unwire(map, entry); 3486 entry = entry->next; 3487 } 3488 if ((lockflags & UVM_LK_EXIT) == 0) 3489 vm_map_unlock(map); 3490 UVMHIST_LOG(maphist,"<- done (OK UNWIRE)",0,0,0,0); 3491 return 0; 3492 } 3493 3494 /* 3495 * wire case: in two passes [XXXCDC: ugly block of code here] 3496 * 3497 * 1: holding the write lock, we create any anonymous maps that need 3498 * to be created. then we clip each map entry to the region to 3499 * be wired and increment its wiring count. 3500 * 3501 * 2: we downgrade to a read lock, and call uvm_fault_wire to fault 3502 * in the pages for any newly wired area (wired_count == 1). 3503 * 3504 * downgrading to a read lock for uvm_fault_wire avoids a possible 3505 * deadlock with another thread that may have faulted on one of 3506 * the pages to be wired (it would mark the page busy, blocking 3507 * us, then in turn block on the map lock that we hold). because 3508 * of problems in the recursive lock package, we cannot upgrade 3509 * to a write lock in vm_map_lookup. thus, any actions that 3510 * require the write lock must be done beforehand. because we 3511 * keep the read lock on the map, the copy-on-write status of the 3512 * entries we modify here cannot change. 3513 */ 3514 3515 while ((entry != &map->header) && (entry->start < end)) { 3516 if (VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 3517 3518 /* 3519 * perform actions of vm_map_lookup that need the 3520 * write lock on the map: create an anonymous map 3521 * for a copy-on-write region, or an anonymous map 3522 * for a zero-fill region. (XXXCDC: submap case 3523 * ok?) 3524 */ 3525 3526 if (!UVM_ET_ISSUBMAP(entry)) { /* not submap */ 3527 if (UVM_ET_ISNEEDSCOPY(entry) && 3528 ((entry->max_protection & VM_PROT_WRITE) || 3529 (entry->object.uvm_obj == NULL))) { 3530 amap_copy(map, entry, 0, start, end); 3531 /* XXXCDC: wait OK? */ 3532 } 3533 } 3534 } 3535 UVM_MAP_CLIP_START(map, entry, start); 3536 UVM_MAP_CLIP_END(map, entry, end); 3537 entry->wired_count++; 3538 3539 /* 3540 * Check for holes 3541 */ 3542 3543 if (entry->protection == VM_PROT_NONE || 3544 (entry->end < end && 3545 (entry->next == &map->header || 3546 entry->next->start > entry->end))) { 3547 3548 /* 3549 * found one. amap creation actions do not need to 3550 * be undone, but the wired counts need to be restored. 3551 */ 3552 3553 while (entry != &map->header && entry->end > start) { 3554 entry->wired_count--; 3555 entry = entry->prev; 3556 } 3557 if ((lockflags & UVM_LK_EXIT) == 0) 3558 vm_map_unlock(map); 3559 UVMHIST_LOG(maphist,"<- done (INVALID WIRE)",0,0,0,0); 3560 return EINVAL; 3561 } 3562 entry = entry->next; 3563 } 3564 3565 /* 3566 * Pass 2. 3567 */ 3568 3569 #ifdef DIAGNOSTIC 3570 timestamp_save = map->timestamp; 3571 #endif 3572 vm_map_busy(map); 3573 vm_map_unlock(map); 3574 3575 rv = 0; 3576 entry = start_entry; 3577 while (entry != &map->header && entry->start < end) { 3578 if (entry->wired_count == 1) { 3579 rv = uvm_fault_wire(map, entry->start, entry->end, 3580 entry->max_protection, 1); 3581 if (rv) { 3582 3583 /* 3584 * wiring failed. break out of the loop. 3585 * we'll clean up the map below, once we 3586 * have a write lock again. 3587 */ 3588 3589 break; 3590 } 3591 } 3592 entry = entry->next; 3593 } 3594 3595 if (rv) { /* failed? */ 3596 3597 /* 3598 * Get back to an exclusive (write) lock. 3599 */ 3600 3601 vm_map_lock(map); 3602 vm_map_unbusy(map); 3603 3604 #ifdef DIAGNOSTIC 3605 if (timestamp_save + 1 != map->timestamp) 3606 panic("uvm_map_pageable: stale map"); 3607 #endif 3608 3609 /* 3610 * first drop the wiring count on all the entries 3611 * which haven't actually been wired yet. 3612 */ 3613 3614 failed_entry = entry; 3615 while (entry != &map->header && entry->start < end) { 3616 entry->wired_count--; 3617 entry = entry->next; 3618 } 3619 3620 /* 3621 * now, unwire all the entries that were successfully 3622 * wired above. 3623 */ 3624 3625 entry = start_entry; 3626 while (entry != failed_entry) { 3627 entry->wired_count--; 3628 if (VM_MAPENT_ISWIRED(entry) == 0) 3629 uvm_map_entry_unwire(map, entry); 3630 entry = entry->next; 3631 } 3632 if ((lockflags & UVM_LK_EXIT) == 0) 3633 vm_map_unlock(map); 3634 UVMHIST_LOG(maphist, "<- done (RV=%jd)", rv,0,0,0); 3635 return (rv); 3636 } 3637 3638 if ((lockflags & UVM_LK_EXIT) == 0) { 3639 vm_map_unbusy(map); 3640 } else { 3641 3642 /* 3643 * Get back to an exclusive (write) lock. 3644 */ 3645 3646 vm_map_lock(map); 3647 vm_map_unbusy(map); 3648 } 3649 3650 UVMHIST_LOG(maphist,"<- done (OK WIRE)",0,0,0,0); 3651 return 0; 3652 } 3653 3654 /* 3655 * uvm_map_pageable_all: special case of uvm_map_pageable - affects 3656 * all mapped regions. 3657 * 3658 * => map must not be locked. 3659 * => if no flags are specified, all regions are unwired. 3660 * => XXXJRT: has some of the same problems as uvm_map_pageable() above. 3661 */ 3662 3663 int 3664 uvm_map_pageable_all(struct vm_map *map, int flags, vsize_t limit) 3665 { 3666 struct vm_map_entry *entry, *failed_entry; 3667 vsize_t size; 3668 int rv; 3669 #ifdef DIAGNOSTIC 3670 u_int timestamp_save; 3671 #endif 3672 UVMHIST_FUNC(__func__); 3673 UVMHIST_CALLARGS(maphist,"(map=%#jx,flags=%#jx)", (uintptr_t)map, flags, 3674 0, 0); 3675 3676 KASSERT(map->flags & VM_MAP_PAGEABLE); 3677 3678 vm_map_lock(map); 3679 3680 /* 3681 * handle wiring and unwiring separately. 3682 */ 3683 3684 if (flags == 0) { /* unwire */ 3685 3686 /* 3687 * POSIX 1003.1b -- munlockall unlocks all regions, 3688 * regardless of how many times mlockall has been called. 3689 */ 3690 3691 for (entry = map->header.next; entry != &map->header; 3692 entry = entry->next) { 3693 if (VM_MAPENT_ISWIRED(entry)) 3694 uvm_map_entry_unwire(map, entry); 3695 } 3696 map->flags &= ~VM_MAP_WIREFUTURE; 3697 vm_map_unlock(map); 3698 UVMHIST_LOG(maphist,"<- done (OK UNWIRE)",0,0,0,0); 3699 return 0; 3700 } 3701 3702 if (flags & MCL_FUTURE) { 3703 3704 /* 3705 * must wire all future mappings; remember this. 3706 */ 3707 3708 map->flags |= VM_MAP_WIREFUTURE; 3709 } 3710 3711 if ((flags & MCL_CURRENT) == 0) { 3712 3713 /* 3714 * no more work to do! 3715 */ 3716 3717 UVMHIST_LOG(maphist,"<- done (OK no wire)",0,0,0,0); 3718 vm_map_unlock(map); 3719 return 0; 3720 } 3721 3722 /* 3723 * wire case: in three passes [XXXCDC: ugly block of code here] 3724 * 3725 * 1: holding the write lock, count all pages mapped by non-wired 3726 * entries. if this would cause us to go over our limit, we fail. 3727 * 3728 * 2: still holding the write lock, we create any anonymous maps that 3729 * need to be created. then we increment its wiring count. 3730 * 3731 * 3: we downgrade to a read lock, and call uvm_fault_wire to fault 3732 * in the pages for any newly wired area (wired_count == 1). 3733 * 3734 * downgrading to a read lock for uvm_fault_wire avoids a possible 3735 * deadlock with another thread that may have faulted on one of 3736 * the pages to be wired (it would mark the page busy, blocking 3737 * us, then in turn block on the map lock that we hold). because 3738 * of problems in the recursive lock package, we cannot upgrade 3739 * to a write lock in vm_map_lookup. thus, any actions that 3740 * require the write lock must be done beforehand. because we 3741 * keep the read lock on the map, the copy-on-write status of the 3742 * entries we modify here cannot change. 3743 */ 3744 3745 for (size = 0, entry = map->header.next; entry != &map->header; 3746 entry = entry->next) { 3747 if (entry->protection != VM_PROT_NONE && 3748 VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 3749 size += entry->end - entry->start; 3750 } 3751 } 3752 3753 if (atop(size) + uvmexp.wired > uvmexp.wiredmax) { 3754 vm_map_unlock(map); 3755 return ENOMEM; 3756 } 3757 3758 if (limit != 0 && 3759 (size + ptoa(pmap_wired_count(vm_map_pmap(map))) > limit)) { 3760 vm_map_unlock(map); 3761 return ENOMEM; 3762 } 3763 3764 /* 3765 * Pass 2. 3766 */ 3767 3768 for (entry = map->header.next; entry != &map->header; 3769 entry = entry->next) { 3770 if (entry->protection == VM_PROT_NONE) 3771 continue; 3772 if (VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 3773 3774 /* 3775 * perform actions of vm_map_lookup that need the 3776 * write lock on the map: create an anonymous map 3777 * for a copy-on-write region, or an anonymous map 3778 * for a zero-fill region. (XXXCDC: submap case 3779 * ok?) 3780 */ 3781 3782 if (!UVM_ET_ISSUBMAP(entry)) { /* not submap */ 3783 if (UVM_ET_ISNEEDSCOPY(entry) && 3784 ((entry->max_protection & VM_PROT_WRITE) || 3785 (entry->object.uvm_obj == NULL))) { 3786 amap_copy(map, entry, 0, entry->start, 3787 entry->end); 3788 /* XXXCDC: wait OK? */ 3789 } 3790 } 3791 } 3792 entry->wired_count++; 3793 } 3794 3795 /* 3796 * Pass 3. 3797 */ 3798 3799 #ifdef DIAGNOSTIC 3800 timestamp_save = map->timestamp; 3801 #endif 3802 vm_map_busy(map); 3803 vm_map_unlock(map); 3804 3805 rv = 0; 3806 for (entry = map->header.next; entry != &map->header; 3807 entry = entry->next) { 3808 if (entry->wired_count == 1) { 3809 rv = uvm_fault_wire(map, entry->start, entry->end, 3810 entry->max_protection, 1); 3811 if (rv) { 3812 3813 /* 3814 * wiring failed. break out of the loop. 3815 * we'll clean up the map below, once we 3816 * have a write lock again. 3817 */ 3818 3819 break; 3820 } 3821 } 3822 } 3823 3824 if (rv) { 3825 3826 /* 3827 * Get back an exclusive (write) lock. 3828 */ 3829 3830 vm_map_lock(map); 3831 vm_map_unbusy(map); 3832 3833 #ifdef DIAGNOSTIC 3834 if (timestamp_save + 1 != map->timestamp) 3835 panic("uvm_map_pageable_all: stale map"); 3836 #endif 3837 3838 /* 3839 * first drop the wiring count on all the entries 3840 * which haven't actually been wired yet. 3841 * 3842 * Skip VM_PROT_NONE entries like we did above. 3843 */ 3844 3845 failed_entry = entry; 3846 for (/* nothing */; entry != &map->header; 3847 entry = entry->next) { 3848 if (entry->protection == VM_PROT_NONE) 3849 continue; 3850 entry->wired_count--; 3851 } 3852 3853 /* 3854 * now, unwire all the entries that were successfully 3855 * wired above. 3856 * 3857 * Skip VM_PROT_NONE entries like we did above. 3858 */ 3859 3860 for (entry = map->header.next; entry != failed_entry; 3861 entry = entry->next) { 3862 if (entry->protection == VM_PROT_NONE) 3863 continue; 3864 entry->wired_count--; 3865 if (VM_MAPENT_ISWIRED(entry)) 3866 uvm_map_entry_unwire(map, entry); 3867 } 3868 vm_map_unlock(map); 3869 UVMHIST_LOG(maphist,"<- done (RV=%jd)", rv,0,0,0); 3870 return (rv); 3871 } 3872 3873 vm_map_unbusy(map); 3874 3875 UVMHIST_LOG(maphist,"<- done (OK WIRE)",0,0,0,0); 3876 return 0; 3877 } 3878 3879 /* 3880 * uvm_map_clean: clean out a map range 3881 * 3882 * => valid flags: 3883 * if (flags & PGO_CLEANIT): dirty pages are cleaned first 3884 * if (flags & PGO_SYNCIO): dirty pages are written synchronously 3885 * if (flags & PGO_DEACTIVATE): any cached pages are deactivated after clean 3886 * if (flags & PGO_FREE): any cached pages are freed after clean 3887 * => returns an error if any part of the specified range isn't mapped 3888 * => never a need to flush amap layer since the anonymous memory has 3889 * no permanent home, but may deactivate pages there 3890 * => called from sys_msync() and sys_madvise() 3891 * => caller must not have map locked 3892 */ 3893 3894 int 3895 uvm_map_clean(struct vm_map *map, vaddr_t start, vaddr_t end, int flags) 3896 { 3897 struct vm_map_entry *current, *entry; 3898 struct uvm_object *uobj; 3899 struct vm_amap *amap; 3900 struct vm_anon *anon; 3901 struct vm_page *pg; 3902 vaddr_t offset; 3903 vsize_t size; 3904 voff_t uoff; 3905 int error, refs; 3906 UVMHIST_FUNC(__func__); 3907 UVMHIST_CALLARGS(maphist,"(map=%#jx,start=%#jx,end=%#jx,flags=%#jx)", 3908 (uintptr_t)map, start, end, flags); 3909 3910 KASSERT((flags & (PGO_FREE|PGO_DEACTIVATE)) != 3911 (PGO_FREE|PGO_DEACTIVATE)); 3912 3913 vm_map_lock(map); 3914 VM_MAP_RANGE_CHECK(map, start, end); 3915 if (!uvm_map_lookup_entry(map, start, &entry)) { 3916 vm_map_unlock(map); 3917 return EFAULT; 3918 } 3919 3920 /* 3921 * Make a first pass to check for holes and wiring problems. 3922 */ 3923 3924 for (current = entry; current->start < end; current = current->next) { 3925 if (UVM_ET_ISSUBMAP(current)) { 3926 vm_map_unlock(map); 3927 return EINVAL; 3928 } 3929 if ((flags & PGO_FREE) != 0 && VM_MAPENT_ISWIRED(entry)) { 3930 vm_map_unlock(map); 3931 return EBUSY; 3932 } 3933 if (end <= current->end) { 3934 break; 3935 } 3936 if (current->end != current->next->start) { 3937 vm_map_unlock(map); 3938 return EFAULT; 3939 } 3940 } 3941 3942 vm_map_busy(map); 3943 vm_map_unlock(map); 3944 error = 0; 3945 for (current = entry; start < end; current = current->next) { 3946 amap = current->aref.ar_amap; /* upper layer */ 3947 uobj = current->object.uvm_obj; /* lower layer */ 3948 KASSERT(start >= current->start); 3949 3950 /* 3951 * No amap cleaning necessary if: 3952 * 3953 * (1) There's no amap. 3954 * 3955 * (2) We're not deactivating or freeing pages. 3956 */ 3957 3958 if (amap == NULL || (flags & (PGO_DEACTIVATE|PGO_FREE)) == 0) 3959 goto flush_object; 3960 3961 offset = start - current->start; 3962 size = MIN(end, current->end) - start; 3963 3964 amap_lock(amap, RW_WRITER); 3965 for ( ; size != 0; size -= PAGE_SIZE, offset += PAGE_SIZE) { 3966 anon = amap_lookup(¤t->aref, offset); 3967 if (anon == NULL) 3968 continue; 3969 3970 KASSERT(anon->an_lock == amap->am_lock); 3971 pg = anon->an_page; 3972 if (pg == NULL) { 3973 continue; 3974 } 3975 if (pg->flags & PG_BUSY) { 3976 continue; 3977 } 3978 3979 switch (flags & (PGO_CLEANIT|PGO_FREE|PGO_DEACTIVATE)) { 3980 3981 /* 3982 * In these first 3 cases, we just deactivate the page. 3983 */ 3984 3985 case PGO_CLEANIT|PGO_FREE: 3986 case PGO_CLEANIT|PGO_DEACTIVATE: 3987 case PGO_DEACTIVATE: 3988 deactivate_it: 3989 /* 3990 * skip the page if it's loaned or wired, 3991 * since it shouldn't be on a paging queue 3992 * at all in these cases. 3993 */ 3994 3995 if (pg->loan_count != 0 || 3996 pg->wire_count != 0) { 3997 continue; 3998 } 3999 KASSERT(pg->uanon == anon); 4000 uvm_pagelock(pg); 4001 uvm_pagedeactivate(pg); 4002 uvm_pageunlock(pg); 4003 continue; 4004 4005 case PGO_FREE: 4006 4007 /* 4008 * If there are multiple references to 4009 * the amap, just deactivate the page. 4010 */ 4011 4012 if (amap_refs(amap) > 1) 4013 goto deactivate_it; 4014 4015 /* skip the page if it's wired */ 4016 if (pg->wire_count != 0) { 4017 continue; 4018 } 4019 amap_unadd(¤t->aref, offset); 4020 refs = --anon->an_ref; 4021 if (refs == 0) { 4022 uvm_anfree(anon); 4023 } 4024 continue; 4025 } 4026 } 4027 amap_unlock(amap); 4028 4029 flush_object: 4030 /* 4031 * flush pages if we've got a valid backing object. 4032 * note that we must always clean object pages before 4033 * freeing them since otherwise we could reveal stale 4034 * data from files. 4035 */ 4036 4037 uoff = current->offset + (start - current->start); 4038 size = MIN(end, current->end) - start; 4039 if (uobj != NULL) { 4040 rw_enter(uobj->vmobjlock, RW_WRITER); 4041 if (uobj->pgops->pgo_put != NULL) 4042 error = (uobj->pgops->pgo_put)(uobj, uoff, 4043 uoff + size, flags | PGO_CLEANIT); 4044 else 4045 error = 0; 4046 } 4047 start += size; 4048 } 4049 vm_map_unbusy(map); 4050 return error; 4051 } 4052 4053 4054 /* 4055 * uvm_map_checkprot: check protection in map 4056 * 4057 * => must allow specified protection in a fully allocated region. 4058 * => map must be read or write locked by caller. 4059 */ 4060 4061 bool 4062 uvm_map_checkprot(struct vm_map *map, vaddr_t start, vaddr_t end, 4063 vm_prot_t protection) 4064 { 4065 struct vm_map_entry *entry; 4066 struct vm_map_entry *tmp_entry; 4067 4068 if (!uvm_map_lookup_entry(map, start, &tmp_entry)) { 4069 return (false); 4070 } 4071 entry = tmp_entry; 4072 while (start < end) { 4073 if (entry == &map->header) { 4074 return (false); 4075 } 4076 4077 /* 4078 * no holes allowed 4079 */ 4080 4081 if (start < entry->start) { 4082 return (false); 4083 } 4084 4085 /* 4086 * check protection associated with entry 4087 */ 4088 4089 if ((entry->protection & protection) != protection) { 4090 return (false); 4091 } 4092 start = entry->end; 4093 entry = entry->next; 4094 } 4095 return (true); 4096 } 4097 4098 /* 4099 * uvmspace_alloc: allocate a vmspace structure. 4100 * 4101 * - structure includes vm_map and pmap 4102 * - XXX: no locking on this structure 4103 * - refcnt set to 1, rest must be init'd by caller 4104 */ 4105 struct vmspace * 4106 uvmspace_alloc(vaddr_t vmin, vaddr_t vmax, bool topdown) 4107 { 4108 struct vmspace *vm; 4109 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 4110 4111 vm = kmem_alloc(sizeof(*vm), KM_SLEEP); 4112 uvmspace_init(vm, NULL, vmin, vmax, topdown); 4113 UVMHIST_LOG(maphist,"<- done (vm=%#jx)", (uintptr_t)vm, 0, 0, 0); 4114 return (vm); 4115 } 4116 4117 /* 4118 * uvmspace_init: initialize a vmspace structure. 4119 * 4120 * - XXX: no locking on this structure 4121 * - refcnt set to 1, rest must be init'd by caller 4122 */ 4123 void 4124 uvmspace_init(struct vmspace *vm, struct pmap *pmap, vaddr_t vmin, 4125 vaddr_t vmax, bool topdown) 4126 { 4127 UVMHIST_FUNC(__func__); 4128 UVMHIST_CALLARGS(maphist, "(vm=%#jx, pmap=%#jx, vmin=%#jx, vmax=%#jx", 4129 (uintptr_t)vm, (uintptr_t)pmap, vmin, vmax); 4130 UVMHIST_LOG(maphist, " topdown=%ju)", topdown, 0, 0, 0); 4131 4132 memset(vm, 0, sizeof(*vm)); 4133 uvm_map_setup(&vm->vm_map, vmin, vmax, VM_MAP_PAGEABLE 4134 | (topdown ? VM_MAP_TOPDOWN : 0) 4135 ); 4136 if (pmap) 4137 pmap_reference(pmap); 4138 else 4139 pmap = pmap_create(); 4140 vm->vm_map.pmap = pmap; 4141 vm->vm_refcnt = 1; 4142 UVMHIST_LOG(maphist,"<- done",0,0,0,0); 4143 } 4144 4145 /* 4146 * uvmspace_share: share a vmspace between two processes 4147 * 4148 * - used for vfork, threads(?) 4149 */ 4150 4151 void 4152 uvmspace_share(struct proc *p1, struct proc *p2) 4153 { 4154 4155 uvmspace_addref(p1->p_vmspace); 4156 p2->p_vmspace = p1->p_vmspace; 4157 } 4158 4159 #if 0 4160 4161 /* 4162 * uvmspace_unshare: ensure that process "p" has its own, unshared, vmspace 4163 * 4164 * - XXX: no locking on vmspace 4165 */ 4166 4167 void 4168 uvmspace_unshare(struct lwp *l) 4169 { 4170 struct proc *p = l->l_proc; 4171 struct vmspace *nvm, *ovm = p->p_vmspace; 4172 4173 if (ovm->vm_refcnt == 1) 4174 /* nothing to do: vmspace isn't shared in the first place */ 4175 return; 4176 4177 /* make a new vmspace, still holding old one */ 4178 nvm = uvmspace_fork(ovm); 4179 4180 kpreempt_disable(); 4181 pmap_deactivate(l); /* unbind old vmspace */ 4182 p->p_vmspace = nvm; 4183 pmap_activate(l); /* switch to new vmspace */ 4184 kpreempt_enable(); 4185 4186 uvmspace_free(ovm); /* drop reference to old vmspace */ 4187 } 4188 4189 #endif 4190 4191 4192 /* 4193 * uvmspace_spawn: a new process has been spawned and needs a vmspace 4194 */ 4195 4196 void 4197 uvmspace_spawn(struct lwp *l, vaddr_t start, vaddr_t end, bool topdown) 4198 { 4199 struct proc *p = l->l_proc; 4200 struct vmspace *nvm; 4201 4202 #ifdef __HAVE_CPU_VMSPACE_EXEC 4203 cpu_vmspace_exec(l, start, end); 4204 #endif 4205 4206 nvm = uvmspace_alloc(start, end, topdown); 4207 kpreempt_disable(); 4208 p->p_vmspace = nvm; 4209 pmap_activate(l); 4210 kpreempt_enable(); 4211 } 4212 4213 /* 4214 * uvmspace_exec: the process wants to exec a new program 4215 */ 4216 4217 void 4218 uvmspace_exec(struct lwp *l, vaddr_t start, vaddr_t end, bool topdown) 4219 { 4220 struct proc *p = l->l_proc; 4221 struct vmspace *nvm, *ovm = p->p_vmspace; 4222 struct vm_map *map; 4223 int flags; 4224 4225 KASSERT(ovm != NULL); 4226 #ifdef __HAVE_CPU_VMSPACE_EXEC 4227 cpu_vmspace_exec(l, start, end); 4228 #endif 4229 4230 map = &ovm->vm_map; 4231 /* 4232 * see if more than one process is using this vmspace... 4233 */ 4234 4235 if (ovm->vm_refcnt == 1 4236 && topdown == ((ovm->vm_map.flags & VM_MAP_TOPDOWN) != 0)) { 4237 4238 /* 4239 * if p is the only process using its vmspace then we can safely 4240 * recycle that vmspace for the program that is being exec'd. 4241 * But only if TOPDOWN matches the requested value for the new 4242 * vm space! 4243 */ 4244 4245 /* 4246 * SYSV SHM semantics require us to kill all segments on an exec 4247 */ 4248 if (uvm_shmexit && ovm->vm_shm) 4249 (*uvm_shmexit)(ovm); 4250 4251 /* 4252 * POSIX 1003.1b -- "lock future mappings" is revoked 4253 * when a process execs another program image. 4254 */ 4255 4256 map->flags &= ~VM_MAP_WIREFUTURE; 4257 4258 /* 4259 * now unmap the old program. 4260 * 4261 * XXX set VM_MAP_DYING for the duration, so pmap_update() 4262 * is not called until the pmap has been totally cleared out 4263 * after pmap_remove_all(), or it can confuse some pmap 4264 * implementations. it would be nice to handle this by 4265 * deferring the pmap_update() while it is known the address 4266 * space is not visible to any user LWP other than curlwp, 4267 * but there isn't an elegant way of inferring that right 4268 * now. 4269 */ 4270 4271 flags = pmap_remove_all(map->pmap) ? UVM_FLAG_VAONLY : 0; 4272 map->flags |= VM_MAP_DYING; 4273 uvm_unmap1(map, vm_map_min(map), vm_map_max(map), flags); 4274 map->flags &= ~VM_MAP_DYING; 4275 pmap_update(map->pmap); 4276 KASSERT(map->header.prev == &map->header); 4277 KASSERT(map->nentries == 0); 4278 4279 /* 4280 * resize the map 4281 */ 4282 4283 vm_map_setmin(map, start); 4284 vm_map_setmax(map, end); 4285 } else { 4286 4287 /* 4288 * p's vmspace is being shared, so we can't reuse it for p since 4289 * it is still being used for others. allocate a new vmspace 4290 * for p 4291 */ 4292 4293 nvm = uvmspace_alloc(start, end, topdown); 4294 4295 /* 4296 * install new vmspace and drop our ref to the old one. 4297 */ 4298 4299 kpreempt_disable(); 4300 pmap_deactivate(l); 4301 p->p_vmspace = nvm; 4302 pmap_activate(l); 4303 kpreempt_enable(); 4304 4305 uvmspace_free(ovm); 4306 } 4307 } 4308 4309 /* 4310 * uvmspace_addref: add a reference to a vmspace. 4311 */ 4312 4313 void 4314 uvmspace_addref(struct vmspace *vm) 4315 { 4316 4317 KASSERT((vm->vm_map.flags & VM_MAP_DYING) == 0); 4318 KASSERT(vm->vm_refcnt > 0); 4319 atomic_inc_uint(&vm->vm_refcnt); 4320 } 4321 4322 /* 4323 * uvmspace_free: free a vmspace data structure 4324 */ 4325 4326 void 4327 uvmspace_free(struct vmspace *vm) 4328 { 4329 struct vm_map_entry *dead_entries; 4330 struct vm_map *map = &vm->vm_map; 4331 int flags; 4332 4333 UVMHIST_FUNC(__func__); 4334 UVMHIST_CALLARGS(maphist,"(vm=%#jx) ref=%jd", (uintptr_t)vm, 4335 vm->vm_refcnt, 0, 0); 4336 4337 membar_release(); 4338 if (atomic_dec_uint_nv(&vm->vm_refcnt) > 0) 4339 return; 4340 membar_acquire(); 4341 4342 /* 4343 * at this point, there should be no other references to the map. 4344 * delete all of the mappings, then destroy the pmap. 4345 */ 4346 4347 map->flags |= VM_MAP_DYING; 4348 flags = pmap_remove_all(map->pmap) ? UVM_FLAG_VAONLY : 0; 4349 4350 /* Get rid of any SYSV shared memory segments. */ 4351 if (uvm_shmexit && vm->vm_shm != NULL) 4352 (*uvm_shmexit)(vm); 4353 4354 if (map->nentries) { 4355 uvm_unmap_remove(map, vm_map_min(map), vm_map_max(map), 4356 &dead_entries, flags); 4357 if (dead_entries != NULL) 4358 uvm_unmap_detach(dead_entries, 0); 4359 } 4360 KASSERT(map->nentries == 0); 4361 KASSERT(map->size == 0); 4362 4363 mutex_destroy(&map->misc_lock); 4364 rw_destroy(&map->lock); 4365 cv_destroy(&map->cv); 4366 pmap_destroy(map->pmap); 4367 kmem_free(vm, sizeof(*vm)); 4368 } 4369 4370 static struct vm_map_entry * 4371 uvm_mapent_clone(struct vm_map *new_map, struct vm_map_entry *old_entry, 4372 int flags) 4373 { 4374 struct vm_map_entry *new_entry; 4375 4376 new_entry = uvm_mapent_alloc(new_map, 0); 4377 /* old_entry -> new_entry */ 4378 uvm_mapent_copy(old_entry, new_entry); 4379 4380 /* new pmap has nothing wired in it */ 4381 new_entry->wired_count = 0; 4382 4383 /* 4384 * gain reference to object backing the map (can't 4385 * be a submap, already checked this case). 4386 */ 4387 4388 if (new_entry->aref.ar_amap) 4389 uvm_map_reference_amap(new_entry, flags); 4390 4391 if (new_entry->object.uvm_obj && 4392 new_entry->object.uvm_obj->pgops->pgo_reference) 4393 new_entry->object.uvm_obj->pgops->pgo_reference( 4394 new_entry->object.uvm_obj); 4395 4396 /* insert entry at end of new_map's entry list */ 4397 uvm_map_entry_link(new_map, new_map->header.prev, 4398 new_entry); 4399 4400 return new_entry; 4401 } 4402 4403 /* 4404 * share the mapping: this means we want the old and 4405 * new entries to share amaps and backing objects. 4406 */ 4407 static void 4408 uvm_mapent_forkshared(struct vm_map *new_map, struct vm_map *old_map, 4409 struct vm_map_entry *old_entry) 4410 { 4411 /* 4412 * if the old_entry needs a new amap (due to prev fork) 4413 * then we need to allocate it now so that we have 4414 * something we own to share with the new_entry. [in 4415 * other words, we need to clear needs_copy] 4416 */ 4417 4418 if (UVM_ET_ISNEEDSCOPY(old_entry)) { 4419 /* get our own amap, clears needs_copy */ 4420 amap_copy(old_map, old_entry, AMAP_COPY_NOCHUNK, 4421 0, 0); 4422 /* XXXCDC: WAITOK??? */ 4423 } 4424 4425 uvm_mapent_clone(new_map, old_entry, AMAP_SHARED); 4426 } 4427 4428 4429 static void 4430 uvm_mapent_forkcopy(struct vm_map *new_map, struct vm_map *old_map, 4431 struct vm_map_entry *old_entry) 4432 { 4433 struct vm_map_entry *new_entry; 4434 4435 /* 4436 * copy-on-write the mapping (using mmap's 4437 * MAP_PRIVATE semantics) 4438 * 4439 * allocate new_entry, adjust reference counts. 4440 * (note that new references are read-only). 4441 */ 4442 4443 new_entry = uvm_mapent_clone(new_map, old_entry, 0); 4444 4445 new_entry->etype |= 4446 (UVM_ET_COPYONWRITE|UVM_ET_NEEDSCOPY); 4447 4448 /* 4449 * the new entry will need an amap. it will either 4450 * need to be copied from the old entry or created 4451 * from scratch (if the old entry does not have an 4452 * amap). can we defer this process until later 4453 * (by setting "needs_copy") or do we need to copy 4454 * the amap now? 4455 * 4456 * we must copy the amap now if any of the following 4457 * conditions hold: 4458 * 1. the old entry has an amap and that amap is 4459 * being shared. this means that the old (parent) 4460 * process is sharing the amap with another 4461 * process. if we do not clear needs_copy here 4462 * we will end up in a situation where both the 4463 * parent and child process are referring to the 4464 * same amap with "needs_copy" set. if the 4465 * parent write-faults, the fault routine will 4466 * clear "needs_copy" in the parent by allocating 4467 * a new amap. this is wrong because the 4468 * parent is supposed to be sharing the old amap 4469 * and the new amap will break that. 4470 * 4471 * 2. if the old entry has an amap and a non-zero 4472 * wire count then we are going to have to call 4473 * amap_cow_now to avoid page faults in the 4474 * parent process. since amap_cow_now requires 4475 * "needs_copy" to be clear we might as well 4476 * clear it here as well. 4477 * 4478 */ 4479 4480 if (old_entry->aref.ar_amap != NULL) { 4481 if ((amap_flags(old_entry->aref.ar_amap) & AMAP_SHARED) != 0 || 4482 VM_MAPENT_ISWIRED(old_entry)) { 4483 4484 amap_copy(new_map, new_entry, 4485 AMAP_COPY_NOCHUNK, 0, 0); 4486 /* XXXCDC: M_WAITOK ... ok? */ 4487 } 4488 } 4489 4490 /* 4491 * if the parent's entry is wired down, then the 4492 * parent process does not want page faults on 4493 * access to that memory. this means that we 4494 * cannot do copy-on-write because we can't write 4495 * protect the old entry. in this case we 4496 * resolve all copy-on-write faults now, using 4497 * amap_cow_now. note that we have already 4498 * allocated any needed amap (above). 4499 */ 4500 4501 if (VM_MAPENT_ISWIRED(old_entry)) { 4502 4503 /* 4504 * resolve all copy-on-write faults now 4505 * (note that there is nothing to do if 4506 * the old mapping does not have an amap). 4507 */ 4508 if (old_entry->aref.ar_amap) 4509 amap_cow_now(new_map, new_entry); 4510 4511 } else { 4512 /* 4513 * setup mappings to trigger copy-on-write faults 4514 * we must write-protect the parent if it has 4515 * an amap and it is not already "needs_copy"... 4516 * if it is already "needs_copy" then the parent 4517 * has already been write-protected by a previous 4518 * fork operation. 4519 */ 4520 if (old_entry->aref.ar_amap && 4521 !UVM_ET_ISNEEDSCOPY(old_entry)) { 4522 if (old_entry->max_protection & VM_PROT_WRITE) { 4523 #ifdef __HAVE_UNLOCKED_PMAP /* XXX temporary */ 4524 uvm_map_lock_entry(old_entry, RW_WRITER); 4525 #else 4526 uvm_map_lock_entry(old_entry, RW_READER); 4527 #endif 4528 pmap_protect(old_map->pmap, 4529 old_entry->start, old_entry->end, 4530 old_entry->protection & ~VM_PROT_WRITE); 4531 uvm_map_unlock_entry(old_entry); 4532 } 4533 old_entry->etype |= UVM_ET_NEEDSCOPY; 4534 } 4535 } 4536 } 4537 4538 /* 4539 * zero the mapping: the new entry will be zero initialized 4540 */ 4541 static void 4542 uvm_mapent_forkzero(struct vm_map *new_map, struct vm_map *old_map, 4543 struct vm_map_entry *old_entry) 4544 { 4545 struct vm_map_entry *new_entry; 4546 4547 new_entry = uvm_mapent_clone(new_map, old_entry, 0); 4548 4549 new_entry->etype |= 4550 (UVM_ET_COPYONWRITE|UVM_ET_NEEDSCOPY); 4551 4552 if (new_entry->aref.ar_amap) { 4553 uvm_map_unreference_amap(new_entry, 0); 4554 new_entry->aref.ar_pageoff = 0; 4555 new_entry->aref.ar_amap = NULL; 4556 } 4557 4558 if (UVM_ET_ISOBJ(new_entry)) { 4559 if (new_entry->object.uvm_obj->pgops->pgo_detach) 4560 new_entry->object.uvm_obj->pgops->pgo_detach( 4561 new_entry->object.uvm_obj); 4562 new_entry->object.uvm_obj = NULL; 4563 new_entry->offset = 0; 4564 new_entry->etype &= ~UVM_ET_OBJ; 4565 } 4566 } 4567 4568 /* 4569 * F O R K - m a i n e n t r y p o i n t 4570 */ 4571 /* 4572 * uvmspace_fork: fork a process' main map 4573 * 4574 * => create a new vmspace for child process from parent. 4575 * => parent's map must not be locked. 4576 */ 4577 4578 struct vmspace * 4579 uvmspace_fork(struct vmspace *vm1) 4580 { 4581 struct vmspace *vm2; 4582 struct vm_map *old_map = &vm1->vm_map; 4583 struct vm_map *new_map; 4584 struct vm_map_entry *old_entry; 4585 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 4586 4587 vm_map_lock(old_map); 4588 4589 vm2 = uvmspace_alloc(vm_map_min(old_map), vm_map_max(old_map), 4590 vm1->vm_map.flags & VM_MAP_TOPDOWN); 4591 memcpy(&vm2->vm_startcopy, &vm1->vm_startcopy, 4592 (char *) (vm1 + 1) - (char *) &vm1->vm_startcopy); 4593 new_map = &vm2->vm_map; /* XXX */ 4594 4595 old_entry = old_map->header.next; 4596 new_map->size = old_map->size; 4597 4598 /* 4599 * go entry-by-entry 4600 */ 4601 4602 while (old_entry != &old_map->header) { 4603 4604 /* 4605 * first, some sanity checks on the old entry 4606 */ 4607 4608 KASSERT(!UVM_ET_ISSUBMAP(old_entry)); 4609 KASSERT(UVM_ET_ISCOPYONWRITE(old_entry) || 4610 !UVM_ET_ISNEEDSCOPY(old_entry)); 4611 4612 switch (old_entry->inheritance) { 4613 case MAP_INHERIT_NONE: 4614 /* 4615 * drop the mapping, modify size 4616 */ 4617 new_map->size -= old_entry->end - old_entry->start; 4618 break; 4619 4620 case MAP_INHERIT_SHARE: 4621 uvm_mapent_forkshared(new_map, old_map, old_entry); 4622 break; 4623 4624 case MAP_INHERIT_COPY: 4625 uvm_mapent_forkcopy(new_map, old_map, old_entry); 4626 break; 4627 4628 case MAP_INHERIT_ZERO: 4629 uvm_mapent_forkzero(new_map, old_map, old_entry); 4630 break; 4631 default: 4632 KASSERT(0); 4633 break; 4634 } 4635 old_entry = old_entry->next; 4636 } 4637 4638 pmap_update(old_map->pmap); 4639 vm_map_unlock(old_map); 4640 4641 if (uvm_shmfork && vm1->vm_shm) 4642 (*uvm_shmfork)(vm1, vm2); 4643 4644 #ifdef PMAP_FORK 4645 pmap_fork(vm1->vm_map.pmap, vm2->vm_map.pmap); 4646 #endif 4647 4648 UVMHIST_LOG(maphist,"<- done",0,0,0,0); 4649 return (vm2); 4650 } 4651 4652 4653 /* 4654 * uvm_mapent_trymerge: try to merge an entry with its neighbors. 4655 * 4656 * => called with map locked. 4657 * => return non zero if successfully merged. 4658 */ 4659 4660 int 4661 uvm_mapent_trymerge(struct vm_map *map, struct vm_map_entry *entry, int flags) 4662 { 4663 struct uvm_object *uobj; 4664 struct vm_map_entry *next; 4665 struct vm_map_entry *prev; 4666 vsize_t size; 4667 int merged = 0; 4668 bool copying; 4669 int newetype; 4670 4671 if (entry->aref.ar_amap != NULL) { 4672 return 0; 4673 } 4674 if ((entry->flags & UVM_MAP_NOMERGE) != 0) { 4675 return 0; 4676 } 4677 4678 uobj = entry->object.uvm_obj; 4679 size = entry->end - entry->start; 4680 copying = (flags & UVM_MERGE_COPYING) != 0; 4681 newetype = copying ? (entry->etype & ~UVM_ET_NEEDSCOPY) : entry->etype; 4682 4683 next = entry->next; 4684 if (next != &map->header && 4685 next->start == entry->end && 4686 ((copying && next->aref.ar_amap != NULL && 4687 amap_refs(next->aref.ar_amap) == 1) || 4688 (!copying && next->aref.ar_amap == NULL)) && 4689 UVM_ET_ISCOMPATIBLE(next, newetype, 4690 uobj, entry->flags, entry->protection, 4691 entry->max_protection, entry->inheritance, entry->advice, 4692 entry->wired_count) && 4693 (uobj == NULL || entry->offset + size == next->offset)) { 4694 int error; 4695 4696 if (copying) { 4697 error = amap_extend(next, size, 4698 AMAP_EXTEND_NOWAIT|AMAP_EXTEND_BACKWARDS); 4699 } else { 4700 error = 0; 4701 } 4702 if (error == 0) { 4703 if (uobj) { 4704 if (uobj->pgops->pgo_detach) { 4705 uobj->pgops->pgo_detach(uobj); 4706 } 4707 } 4708 4709 entry->end = next->end; 4710 clear_hints(map, next); 4711 uvm_map_entry_unlink(map, next); 4712 if (copying) { 4713 entry->aref = next->aref; 4714 entry->etype &= ~UVM_ET_NEEDSCOPY; 4715 } 4716 uvm_map_check(map, "trymerge forwardmerge"); 4717 uvm_mapent_free(next); 4718 merged++; 4719 } 4720 } 4721 4722 prev = entry->prev; 4723 if (prev != &map->header && 4724 prev->end == entry->start && 4725 ((copying && !merged && prev->aref.ar_amap != NULL && 4726 amap_refs(prev->aref.ar_amap) == 1) || 4727 (!copying && prev->aref.ar_amap == NULL)) && 4728 UVM_ET_ISCOMPATIBLE(prev, newetype, 4729 uobj, entry->flags, entry->protection, 4730 entry->max_protection, entry->inheritance, entry->advice, 4731 entry->wired_count) && 4732 (uobj == NULL || 4733 prev->offset + prev->end - prev->start == entry->offset)) { 4734 int error; 4735 4736 if (copying) { 4737 error = amap_extend(prev, size, 4738 AMAP_EXTEND_NOWAIT|AMAP_EXTEND_FORWARDS); 4739 } else { 4740 error = 0; 4741 } 4742 if (error == 0) { 4743 if (uobj) { 4744 if (uobj->pgops->pgo_detach) { 4745 uobj->pgops->pgo_detach(uobj); 4746 } 4747 entry->offset = prev->offset; 4748 } 4749 4750 entry->start = prev->start; 4751 clear_hints(map, prev); 4752 uvm_map_entry_unlink(map, prev); 4753 if (copying) { 4754 entry->aref = prev->aref; 4755 entry->etype &= ~UVM_ET_NEEDSCOPY; 4756 } 4757 uvm_map_check(map, "trymerge backmerge"); 4758 uvm_mapent_free(prev); 4759 merged++; 4760 } 4761 } 4762 4763 return merged; 4764 } 4765 4766 /* 4767 * uvm_map_setup: init map 4768 * 4769 * => map must not be in service yet. 4770 */ 4771 4772 void 4773 uvm_map_setup(struct vm_map *map, vaddr_t vmin, vaddr_t vmax, int flags) 4774 { 4775 4776 rb_tree_init(&map->rb_tree, &uvm_map_tree_ops); 4777 map->header.next = map->header.prev = &map->header; 4778 map->nentries = 0; 4779 map->size = 0; 4780 map->ref_count = 1; 4781 vm_map_setmin(map, vmin); 4782 vm_map_setmax(map, vmax); 4783 map->flags = flags; 4784 map->first_free = &map->header; 4785 map->hint = &map->header; 4786 map->timestamp = 0; 4787 map->busy = NULL; 4788 4789 rw_init(&map->lock); 4790 cv_init(&map->cv, "vm_map"); 4791 mutex_init(&map->misc_lock, MUTEX_DRIVER, IPL_NONE); 4792 } 4793 4794 /* 4795 * U N M A P - m a i n e n t r y p o i n t 4796 */ 4797 4798 /* 4799 * uvm_unmap1: remove mappings from a vm_map (from "start" up to "stop") 4800 * 4801 * => caller must check alignment and size 4802 * => map must be unlocked (we will lock it) 4803 * => flags is UVM_FLAG_QUANTUM or 0. 4804 */ 4805 4806 void 4807 uvm_unmap1(struct vm_map *map, vaddr_t start, vaddr_t end, int flags) 4808 { 4809 struct vm_map_entry *dead_entries; 4810 UVMHIST_FUNC(__func__); 4811 UVMHIST_CALLARGS(maphist, " (map=%#jx, start=%#jx, end=%#jx)", 4812 (uintptr_t)map, start, end, 0); 4813 4814 KASSERTMSG(start < end, 4815 "%s: map %p: start %#jx < end %#jx", __func__, map, 4816 (uintmax_t)start, (uintmax_t)end); 4817 if (map == kernel_map) { 4818 LOCKDEBUG_MEM_CHECK((void *)start, end - start); 4819 } 4820 4821 /* 4822 * work now done by helper functions. wipe the pmap's and then 4823 * detach from the dead entries... 4824 */ 4825 vm_map_lock(map); 4826 uvm_unmap_remove(map, start, end, &dead_entries, flags); 4827 vm_map_unlock(map); 4828 4829 if (dead_entries != NULL) 4830 uvm_unmap_detach(dead_entries, 0); 4831 4832 UVMHIST_LOG(maphist, "<- done", 0,0,0,0); 4833 } 4834 4835 4836 /* 4837 * uvm_map_reference: add reference to a map 4838 * 4839 * => map need not be locked 4840 */ 4841 4842 void 4843 uvm_map_reference(struct vm_map *map) 4844 { 4845 4846 atomic_inc_uint(&map->ref_count); 4847 } 4848 4849 void 4850 uvm_map_lock_entry(struct vm_map_entry *entry, krw_t op) 4851 { 4852 4853 if (entry->aref.ar_amap != NULL) { 4854 amap_lock(entry->aref.ar_amap, op); 4855 } 4856 if (UVM_ET_ISOBJ(entry)) { 4857 rw_enter(entry->object.uvm_obj->vmobjlock, op); 4858 } 4859 } 4860 4861 void 4862 uvm_map_unlock_entry(struct vm_map_entry *entry) 4863 { 4864 4865 if (UVM_ET_ISOBJ(entry)) { 4866 rw_exit(entry->object.uvm_obj->vmobjlock); 4867 } 4868 if (entry->aref.ar_amap != NULL) { 4869 amap_unlock(entry->aref.ar_amap); 4870 } 4871 } 4872 4873 #define UVM_VOADDR_TYPE_MASK 0x3UL 4874 #define UVM_VOADDR_TYPE_UOBJ 0x1UL 4875 #define UVM_VOADDR_TYPE_ANON 0x2UL 4876 #define UVM_VOADDR_OBJECT_MASK ~UVM_VOADDR_TYPE_MASK 4877 4878 #define UVM_VOADDR_GET_TYPE(voa) \ 4879 ((voa)->object & UVM_VOADDR_TYPE_MASK) 4880 #define UVM_VOADDR_GET_OBJECT(voa) \ 4881 ((voa)->object & UVM_VOADDR_OBJECT_MASK) 4882 #define UVM_VOADDR_SET_OBJECT(voa, obj, type) \ 4883 do { \ 4884 KASSERT(((uintptr_t)(obj) & UVM_VOADDR_TYPE_MASK) == 0); \ 4885 (voa)->object = ((uintptr_t)(obj)) | (type); \ 4886 } while (/*CONSTCOND*/0) 4887 4888 #define UVM_VOADDR_GET_UOBJ(voa) \ 4889 ((struct uvm_object *)UVM_VOADDR_GET_OBJECT(voa)) 4890 #define UVM_VOADDR_SET_UOBJ(voa, uobj) \ 4891 UVM_VOADDR_SET_OBJECT(voa, uobj, UVM_VOADDR_TYPE_UOBJ) 4892 4893 #define UVM_VOADDR_GET_ANON(voa) \ 4894 ((struct vm_anon *)UVM_VOADDR_GET_OBJECT(voa)) 4895 #define UVM_VOADDR_SET_ANON(voa, anon) \ 4896 UVM_VOADDR_SET_OBJECT(voa, anon, UVM_VOADDR_TYPE_ANON) 4897 4898 /* 4899 * uvm_voaddr_acquire: returns the virtual object address corresponding 4900 * to the specified virtual address. 4901 * 4902 * => resolves COW so the true page identity is tracked. 4903 * 4904 * => acquires a reference on the page's owner (uvm_object or vm_anon) 4905 */ 4906 bool 4907 uvm_voaddr_acquire(struct vm_map * const map, vaddr_t const va, 4908 struct uvm_voaddr * const voaddr) 4909 { 4910 struct vm_map_entry *entry; 4911 struct vm_anon *anon = NULL; 4912 bool result = false; 4913 bool exclusive = false; 4914 void (*unlock_fn)(struct vm_map *); 4915 4916 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 4917 UVMHIST_LOG(maphist,"(map=%#jx,va=%#jx)", (uintptr_t)map, va, 0, 0); 4918 4919 const vaddr_t start = trunc_page(va); 4920 const vaddr_t end = round_page(va+1); 4921 4922 lookup_again: 4923 if (__predict_false(exclusive)) { 4924 vm_map_lock(map); 4925 unlock_fn = vm_map_unlock; 4926 } else { 4927 vm_map_lock_read(map); 4928 unlock_fn = vm_map_unlock_read; 4929 } 4930 4931 if (__predict_false(!uvm_map_lookup_entry(map, start, &entry))) { 4932 unlock_fn(map); 4933 UVMHIST_LOG(maphist,"<- done (no entry)",0,0,0,0); 4934 return false; 4935 } 4936 4937 if (__predict_false(entry->protection == VM_PROT_NONE)) { 4938 unlock_fn(map); 4939 UVMHIST_LOG(maphist,"<- done (PROT_NONE)",0,0,0,0); 4940 return false; 4941 } 4942 4943 /* 4944 * We have a fast path for the common case of "no COW resolution 4945 * needed" whereby we have taken a read lock on the map and if 4946 * we don't encounter any need to create a vm_anon then great! 4947 * But if we do, we loop around again, instead taking an exclusive 4948 * lock so that we can perform the fault. 4949 * 4950 * In the event that we have to resolve the fault, we do nearly the 4951 * same work as uvm_map_pageable() does: 4952 * 4953 * 1: holding the write lock, we create any anonymous maps that need 4954 * to be created. however, we do NOT need to clip the map entries 4955 * in this case. 4956 * 4957 * 2: we downgrade to a read lock, and call uvm_fault_wire to fault 4958 * in the page (assuming the entry is not already wired). this 4959 * is done because we need the vm_anon to be present. 4960 */ 4961 if (__predict_true(!VM_MAPENT_ISWIRED(entry))) { 4962 4963 bool need_fault = false; 4964 4965 /* 4966 * perform the action of vm_map_lookup that need the 4967 * write lock on the map: create an anonymous map for 4968 * a copy-on-write region, or an anonymous map for 4969 * a zero-fill region. 4970 */ 4971 if (__predict_false(UVM_ET_ISSUBMAP(entry))) { 4972 unlock_fn(map); 4973 UVMHIST_LOG(maphist,"<- done (submap)",0,0,0,0); 4974 return false; 4975 } 4976 if (__predict_false(UVM_ET_ISNEEDSCOPY(entry) && 4977 ((entry->max_protection & VM_PROT_WRITE) || 4978 (entry->object.uvm_obj == NULL)))) { 4979 if (!exclusive) { 4980 /* need to take the slow path */ 4981 KASSERT(unlock_fn == vm_map_unlock_read); 4982 vm_map_unlock_read(map); 4983 exclusive = true; 4984 goto lookup_again; 4985 } 4986 need_fault = true; 4987 amap_copy(map, entry, 0, start, end); 4988 /* XXXCDC: wait OK? */ 4989 } 4990 4991 /* 4992 * do a quick check to see if the fault has already 4993 * been resolved to the upper layer. 4994 */ 4995 if (__predict_true(entry->aref.ar_amap != NULL && 4996 need_fault == false)) { 4997 amap_lock(entry->aref.ar_amap, RW_WRITER); 4998 anon = amap_lookup(&entry->aref, start - entry->start); 4999 if (__predict_true(anon != NULL)) { 5000 /* amap unlocked below */ 5001 goto found_anon; 5002 } 5003 amap_unlock(entry->aref.ar_amap); 5004 need_fault = true; 5005 } 5006 5007 /* 5008 * we predict this test as false because if we reach 5009 * this point, then we are likely dealing with a 5010 * shared memory region backed by a uvm_object, in 5011 * which case a fault to create the vm_anon is not 5012 * necessary. 5013 */ 5014 if (__predict_false(need_fault)) { 5015 if (exclusive) { 5016 vm_map_busy(map); 5017 vm_map_unlock(map); 5018 unlock_fn = vm_map_unbusy; 5019 } 5020 5021 if (uvm_fault_wire(map, start, end, 5022 entry->max_protection, 1)) { 5023 /* wiring failed */ 5024 unlock_fn(map); 5025 UVMHIST_LOG(maphist,"<- done (wire failed)", 5026 0,0,0,0); 5027 return false; 5028 } 5029 5030 /* 5031 * now that we have resolved the fault, we can unwire 5032 * the page. 5033 */ 5034 if (exclusive) { 5035 vm_map_lock(map); 5036 vm_map_unbusy(map); 5037 unlock_fn = vm_map_unlock; 5038 } 5039 5040 uvm_fault_unwire_locked(map, start, end); 5041 } 5042 } 5043 5044 /* check the upper layer */ 5045 if (entry->aref.ar_amap) { 5046 amap_lock(entry->aref.ar_amap, RW_WRITER); 5047 anon = amap_lookup(&entry->aref, start - entry->start); 5048 if (anon) { 5049 found_anon: KASSERT(anon->an_lock == entry->aref.ar_amap->am_lock); 5050 anon->an_ref++; 5051 rw_obj_hold(anon->an_lock); 5052 KASSERT(anon->an_ref != 0); 5053 UVM_VOADDR_SET_ANON(voaddr, anon); 5054 voaddr->offset = va & PAGE_MASK; 5055 result = true; 5056 } 5057 amap_unlock(entry->aref.ar_amap); 5058 } 5059 5060 /* check the lower layer */ 5061 if (!result && UVM_ET_ISOBJ(entry)) { 5062 struct uvm_object *uobj = entry->object.uvm_obj; 5063 5064 KASSERT(uobj != NULL); 5065 (*uobj->pgops->pgo_reference)(uobj); 5066 UVM_VOADDR_SET_UOBJ(voaddr, uobj); 5067 voaddr->offset = entry->offset + (va - entry->start); 5068 result = true; 5069 } 5070 5071 unlock_fn(map); 5072 5073 if (result) { 5074 UVMHIST_LOG(maphist, 5075 "<- done OK (type=%jd,owner=%#jx,offset=%#jx)", 5076 UVM_VOADDR_GET_TYPE(voaddr), 5077 UVM_VOADDR_GET_OBJECT(voaddr), 5078 voaddr->offset, 0); 5079 } else { 5080 UVMHIST_LOG(maphist,"<- done (failed)",0,0,0,0); 5081 } 5082 5083 return result; 5084 } 5085 5086 /* 5087 * uvm_voaddr_release: release the references held by the 5088 * vitual object address. 5089 */ 5090 void 5091 uvm_voaddr_release(struct uvm_voaddr * const voaddr) 5092 { 5093 5094 switch (UVM_VOADDR_GET_TYPE(voaddr)) { 5095 case UVM_VOADDR_TYPE_UOBJ: { 5096 struct uvm_object * const uobj = UVM_VOADDR_GET_UOBJ(voaddr); 5097 5098 KASSERT(uobj != NULL); 5099 KASSERT(uobj->pgops->pgo_detach != NULL); 5100 (*uobj->pgops->pgo_detach)(uobj); 5101 break; 5102 } 5103 case UVM_VOADDR_TYPE_ANON: { 5104 struct vm_anon * const anon = UVM_VOADDR_GET_ANON(voaddr); 5105 krwlock_t *lock; 5106 5107 KASSERT(anon != NULL); 5108 rw_enter((lock = anon->an_lock), RW_WRITER); 5109 KASSERT(anon->an_ref > 0); 5110 if (--anon->an_ref == 0) { 5111 uvm_anfree(anon); 5112 } 5113 rw_exit(lock); 5114 rw_obj_free(lock); 5115 break; 5116 } 5117 default: 5118 panic("uvm_voaddr_release: bad type"); 5119 } 5120 memset(voaddr, 0, sizeof(*voaddr)); 5121 } 5122 5123 /* 5124 * uvm_voaddr_compare: compare two uvm_voaddr objects. 5125 * 5126 * => memcmp() semantics 5127 */ 5128 int 5129 uvm_voaddr_compare(const struct uvm_voaddr * const voaddr1, 5130 const struct uvm_voaddr * const voaddr2) 5131 { 5132 const uintptr_t type1 = UVM_VOADDR_GET_TYPE(voaddr1); 5133 const uintptr_t type2 = UVM_VOADDR_GET_TYPE(voaddr2); 5134 5135 KASSERT(type1 == UVM_VOADDR_TYPE_UOBJ || 5136 type1 == UVM_VOADDR_TYPE_ANON); 5137 5138 KASSERT(type2 == UVM_VOADDR_TYPE_UOBJ || 5139 type2 == UVM_VOADDR_TYPE_ANON); 5140 5141 if (type1 < type2) 5142 return -1; 5143 if (type1 > type2) 5144 return 1; 5145 5146 const uintptr_t addr1 = UVM_VOADDR_GET_OBJECT(voaddr1); 5147 const uintptr_t addr2 = UVM_VOADDR_GET_OBJECT(voaddr2); 5148 5149 if (addr1 < addr2) 5150 return -1; 5151 if (addr1 > addr2) 5152 return 1; 5153 5154 if (voaddr1->offset < voaddr2->offset) 5155 return -1; 5156 if (voaddr1->offset > voaddr2->offset) 5157 return 1; 5158 5159 return 0; 5160 } 5161 5162 #if defined(DDB) || defined(DEBUGPRINT) 5163 5164 /* 5165 * uvm_map_printit: actually prints the map 5166 */ 5167 5168 void 5169 uvm_map_printit(struct vm_map *map, bool full, 5170 void (*pr)(const char *, ...)) 5171 { 5172 struct vm_map_entry *entry; 5173 5174 (*pr)("MAP %p: [%#lx->%#lx]\n", map, vm_map_min(map), 5175 vm_map_max(map)); 5176 (*pr)("\t#ent=%d, sz=%d, ref=%d, version=%d, flags=%#x\n", 5177 map->nentries, map->size, map->ref_count, map->timestamp, 5178 map->flags); 5179 (*pr)("\tpmap=%p(resident=%ld, wired=%ld)\n", map->pmap, 5180 pmap_resident_count(map->pmap), pmap_wired_count(map->pmap)); 5181 if (!full) 5182 return; 5183 for (entry = map->header.next; entry != &map->header; 5184 entry = entry->next) { 5185 (*pr)(" - %p: %#lx->%#lx: obj=%p/%#llx, amap=%p/%d\n", 5186 entry, entry->start, entry->end, entry->object.uvm_obj, 5187 (long long)entry->offset, entry->aref.ar_amap, 5188 entry->aref.ar_pageoff); 5189 (*pr)( 5190 "\tsubmap=%c, cow=%c, nc=%c, prot(max)=%d/%d, inh=%d, " 5191 "wc=%d, adv=%d%s\n", 5192 (entry->etype & UVM_ET_SUBMAP) ? 'T' : 'F', 5193 (entry->etype & UVM_ET_COPYONWRITE) ? 'T' : 'F', 5194 (entry->etype & UVM_ET_NEEDSCOPY) ? 'T' : 'F', 5195 entry->protection, entry->max_protection, 5196 entry->inheritance, entry->wired_count, entry->advice, 5197 entry == map->first_free ? " (first_free)" : ""); 5198 } 5199 } 5200 5201 void 5202 uvm_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 5203 { 5204 struct vm_map *map; 5205 5206 for (map = kernel_map;;) { 5207 struct vm_map_entry *entry; 5208 5209 if (!uvm_map_lookup_entry_bytree(map, (vaddr_t)addr, &entry)) { 5210 break; 5211 } 5212 (*pr)("%p is %p+%zu from VMMAP %p\n", 5213 (void *)addr, (void *)entry->start, 5214 (size_t)(addr - (uintptr_t)entry->start), map); 5215 if (!UVM_ET_ISSUBMAP(entry)) { 5216 break; 5217 } 5218 map = entry->object.sub_map; 5219 } 5220 } 5221 5222 #endif /* DDB || DEBUGPRINT */ 5223 5224 #ifndef __USER_VA0_IS_SAFE 5225 static int 5226 sysctl_user_va0_disable(SYSCTLFN_ARGS) 5227 { 5228 struct sysctlnode node; 5229 int t, error; 5230 5231 node = *rnode; 5232 node.sysctl_data = &t; 5233 t = user_va0_disable; 5234 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 5235 if (error || newp == NULL) 5236 return (error); 5237 5238 if (!t && user_va0_disable && 5239 kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_MAP_VA_ZERO, 0, 5240 NULL, NULL, NULL)) 5241 return EPERM; 5242 5243 user_va0_disable = !!t; 5244 return 0; 5245 } 5246 #endif 5247 5248 static int 5249 fill_vmentry(struct lwp *l, struct proc *p, struct kinfo_vmentry *kve, 5250 struct vm_map *m, struct vm_map_entry *e) 5251 { 5252 #ifndef _RUMPKERNEL 5253 int error; 5254 5255 memset(kve, 0, sizeof(*kve)); 5256 KASSERT(e != NULL); 5257 if (UVM_ET_ISOBJ(e)) { 5258 struct uvm_object *uobj = e->object.uvm_obj; 5259 KASSERT(uobj != NULL); 5260 kve->kve_ref_count = uobj->uo_refs; 5261 kve->kve_count = uobj->uo_npages; 5262 if (UVM_OBJ_IS_VNODE(uobj)) { 5263 struct vattr va; 5264 struct vnode *vp = (struct vnode *)uobj; 5265 vn_lock(vp, LK_SHARED | LK_RETRY); 5266 error = VOP_GETATTR(vp, &va, l->l_cred); 5267 VOP_UNLOCK(vp); 5268 kve->kve_type = KVME_TYPE_VNODE; 5269 if (error == 0) { 5270 kve->kve_vn_size = vp->v_size; 5271 kve->kve_vn_type = (int)vp->v_type; 5272 kve->kve_vn_mode = va.va_mode; 5273 kve->kve_vn_rdev = va.va_rdev; 5274 kve->kve_vn_fileid = va.va_fileid; 5275 kve->kve_vn_fsid = va.va_fsid; 5276 error = vnode_to_path(kve->kve_path, 5277 sizeof(kve->kve_path) / 2, vp, l, p); 5278 } 5279 } else if (UVM_OBJ_IS_KERN_OBJECT(uobj)) { 5280 kve->kve_type = KVME_TYPE_KERN; 5281 } else if (UVM_OBJ_IS_DEVICE(uobj)) { 5282 kve->kve_type = KVME_TYPE_DEVICE; 5283 } else if (UVM_OBJ_IS_AOBJ(uobj)) { 5284 kve->kve_type = KVME_TYPE_ANON; 5285 } else { 5286 kve->kve_type = KVME_TYPE_OBJECT; 5287 } 5288 } else if (UVM_ET_ISSUBMAP(e)) { 5289 struct vm_map *map = e->object.sub_map; 5290 KASSERT(map != NULL); 5291 kve->kve_ref_count = map->ref_count; 5292 kve->kve_count = map->nentries; 5293 kve->kve_type = KVME_TYPE_SUBMAP; 5294 } else 5295 kve->kve_type = KVME_TYPE_UNKNOWN; 5296 5297 kve->kve_start = e->start; 5298 kve->kve_end = e->end; 5299 kve->kve_offset = e->offset; 5300 kve->kve_wired_count = e->wired_count; 5301 kve->kve_inheritance = e->inheritance; 5302 kve->kve_attributes = 0; /* unused */ 5303 kve->kve_advice = e->advice; 5304 #define PROT(p) (((p) & VM_PROT_READ) ? KVME_PROT_READ : 0) | \ 5305 (((p) & VM_PROT_WRITE) ? KVME_PROT_WRITE : 0) | \ 5306 (((p) & VM_PROT_EXECUTE) ? KVME_PROT_EXEC : 0) 5307 kve->kve_protection = PROT(e->protection); 5308 kve->kve_max_protection = PROT(e->max_protection); 5309 kve->kve_flags |= (e->etype & UVM_ET_COPYONWRITE) 5310 ? KVME_FLAG_COW : 0; 5311 kve->kve_flags |= (e->etype & UVM_ET_NEEDSCOPY) 5312 ? KVME_FLAG_NEEDS_COPY : 0; 5313 kve->kve_flags |= (m->flags & VM_MAP_TOPDOWN) 5314 ? KVME_FLAG_GROWS_DOWN : KVME_FLAG_GROWS_UP; 5315 kve->kve_flags |= (m->flags & VM_MAP_PAGEABLE) 5316 ? KVME_FLAG_PAGEABLE : 0; 5317 #endif 5318 return 0; 5319 } 5320 5321 static int 5322 fill_vmentries(struct lwp *l, pid_t pid, u_int elem_size, void *oldp, 5323 size_t *oldlenp) 5324 { 5325 int error; 5326 struct proc *p; 5327 struct kinfo_vmentry *vme; 5328 struct vmspace *vm; 5329 struct vm_map *map; 5330 struct vm_map_entry *entry; 5331 char *dp; 5332 size_t count, vmesize; 5333 5334 if (elem_size == 0 || elem_size > 2 * sizeof(*vme)) 5335 return EINVAL; 5336 5337 if (oldp) { 5338 if (*oldlenp > 10UL * 1024UL * 1024UL) 5339 return E2BIG; 5340 count = *oldlenp / elem_size; 5341 if (count == 0) 5342 return ENOMEM; 5343 vmesize = count * sizeof(*vme); 5344 } else 5345 vmesize = 0; 5346 5347 if ((error = proc_find_locked(l, &p, pid)) != 0) 5348 return error; 5349 5350 vme = NULL; 5351 count = 0; 5352 5353 if ((error = proc_vmspace_getref(p, &vm)) != 0) 5354 goto out; 5355 5356 map = &vm->vm_map; 5357 vm_map_lock_read(map); 5358 5359 dp = oldp; 5360 if (oldp) 5361 vme = kmem_alloc(vmesize, KM_SLEEP); 5362 for (entry = map->header.next; entry != &map->header; 5363 entry = entry->next) { 5364 if (oldp && (dp - (char *)oldp) < vmesize) { 5365 error = fill_vmentry(l, p, &vme[count], map, entry); 5366 if (error) 5367 goto out; 5368 dp += elem_size; 5369 } 5370 count++; 5371 } 5372 vm_map_unlock_read(map); 5373 uvmspace_free(vm); 5374 5375 out: 5376 if (pid != -1) 5377 mutex_exit(p->p_lock); 5378 if (error == 0) { 5379 const u_int esize = uimin(sizeof(*vme), elem_size); 5380 dp = oldp; 5381 for (size_t i = 0; i < count; i++) { 5382 if (oldp && (dp - (char *)oldp) < vmesize) { 5383 error = sysctl_copyout(l, &vme[i], dp, esize); 5384 if (error) 5385 break; 5386 dp += elem_size; 5387 } else 5388 break; 5389 } 5390 count *= elem_size; 5391 if (oldp != NULL && *oldlenp < count) 5392 error = ENOSPC; 5393 *oldlenp = count; 5394 } 5395 if (vme) 5396 kmem_free(vme, vmesize); 5397 return error; 5398 } 5399 5400 static int 5401 sysctl_vmproc(SYSCTLFN_ARGS) 5402 { 5403 int error; 5404 5405 if (namelen == 1 && name[0] == CTL_QUERY) 5406 return (sysctl_query(SYSCTLFN_CALL(rnode))); 5407 5408 if (namelen == 0) 5409 return EINVAL; 5410 5411 switch (name[0]) { 5412 case VM_PROC_MAP: 5413 if (namelen != 3) 5414 return EINVAL; 5415 sysctl_unlock(); 5416 error = fill_vmentries(l, name[1], name[2], oldp, oldlenp); 5417 sysctl_relock(); 5418 return error; 5419 default: 5420 return EINVAL; 5421 } 5422 } 5423 5424 SYSCTL_SETUP(sysctl_uvmmap_setup, "sysctl uvmmap setup") 5425 { 5426 5427 sysctl_createv(clog, 0, NULL, NULL, 5428 CTLFLAG_PERMANENT, 5429 CTLTYPE_STRUCT, "proc", 5430 SYSCTL_DESCR("Process vm information"), 5431 sysctl_vmproc, 0, NULL, 0, 5432 CTL_VM, VM_PROC, CTL_EOL); 5433 #ifndef __USER_VA0_IS_SAFE 5434 sysctl_createv(clog, 0, NULL, NULL, 5435 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 5436 CTLTYPE_INT, "user_va0_disable", 5437 SYSCTL_DESCR("Disable VA 0"), 5438 sysctl_user_va0_disable, 0, &user_va0_disable, 0, 5439 CTL_VM, CTL_CREATE, CTL_EOL); 5440 #endif 5441 } 5442