1 /* $NetBSD: uvm_map.c,v 1.407 2023/08/03 03:15:48 rin 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 1.407 2023/08/03 03:15:48 rin 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 vmspace structures. 148 */ 149 150 static struct pool_cache uvm_vmspace_cache; 151 152 /* 153 * cache for dynamically-allocated map entries. 154 */ 155 156 static struct pool_cache uvm_map_entry_cache; 157 158 #ifdef PMAP_GROWKERNEL 159 /* 160 * This global represents the end of the kernel virtual address 161 * space. If we want to exceed this, we must grow the kernel 162 * virtual address space dynamically. 163 * 164 * Note, this variable is locked by kernel_map's lock. 165 */ 166 vaddr_t uvm_maxkaddr; 167 #endif 168 169 #ifndef __USER_VA0_IS_SAFE 170 #ifndef __USER_VA0_DISABLE_DEFAULT 171 #define __USER_VA0_DISABLE_DEFAULT 1 172 #endif 173 #ifdef USER_VA0_DISABLE_DEFAULT /* kernel config option overrides */ 174 #undef __USER_VA0_DISABLE_DEFAULT 175 #define __USER_VA0_DISABLE_DEFAULT USER_VA0_DISABLE_DEFAULT 176 #endif 177 int user_va0_disable = __USER_VA0_DISABLE_DEFAULT; 178 #endif 179 180 /* 181 * macros 182 */ 183 184 /* 185 * uvm_map_align_va: round down or up virtual address 186 */ 187 static __inline void 188 uvm_map_align_va(vaddr_t *vap, vsize_t align, int topdown) 189 { 190 191 KASSERT(powerof2(align)); 192 193 if (align != 0 && (*vap & (align - 1)) != 0) { 194 if (topdown) 195 *vap = rounddown2(*vap, align); 196 else 197 *vap = roundup2(*vap, align); 198 } 199 } 200 201 /* 202 * UVM_ET_ISCOMPATIBLE: check some requirements for map entry merging 203 */ 204 extern struct vm_map *pager_map; 205 206 #define UVM_ET_ISCOMPATIBLE(ent, type, uobj, meflags, \ 207 prot, maxprot, inh, adv, wire) \ 208 ((ent)->etype == (type) && \ 209 (((ent)->flags ^ (meflags)) & (UVM_MAP_NOMERGE)) == 0 && \ 210 (ent)->object.uvm_obj == (uobj) && \ 211 (ent)->protection == (prot) && \ 212 (ent)->max_protection == (maxprot) && \ 213 (ent)->inheritance == (inh) && \ 214 (ent)->advice == (adv) && \ 215 (ent)->wired_count == (wire)) 216 217 /* 218 * uvm_map_entry_link: insert entry into a map 219 * 220 * => map must be locked 221 */ 222 #define uvm_map_entry_link(map, after_where, entry) do { \ 223 uvm_mapent_check(entry); \ 224 (map)->nentries++; \ 225 (entry)->prev = (after_where); \ 226 (entry)->next = (after_where)->next; \ 227 (entry)->prev->next = (entry); \ 228 (entry)->next->prev = (entry); \ 229 uvm_rb_insert((map), (entry)); \ 230 } while (/*CONSTCOND*/ 0) 231 232 /* 233 * uvm_map_entry_unlink: remove entry from a map 234 * 235 * => map must be locked 236 */ 237 #define uvm_map_entry_unlink(map, entry) do { \ 238 KASSERT((entry) != (map)->first_free); \ 239 KASSERT((entry) != (map)->hint); \ 240 uvm_mapent_check(entry); \ 241 (map)->nentries--; \ 242 (entry)->next->prev = (entry)->prev; \ 243 (entry)->prev->next = (entry)->next; \ 244 uvm_rb_remove((map), (entry)); \ 245 } while (/*CONSTCOND*/ 0) 246 247 /* 248 * SAVE_HINT: saves the specified entry as the hint for future lookups. 249 * 250 * => map need not be locked. 251 */ 252 #define SAVE_HINT(map, check, value) do { \ 253 if ((map)->hint == (check)) \ 254 (map)->hint = (value); \ 255 } while (/*CONSTCOND*/ 0) 256 257 /* 258 * clear_hints: ensure that hints don't point to the entry. 259 * 260 * => map must be write-locked. 261 */ 262 static void 263 clear_hints(struct vm_map *map, struct vm_map_entry *ent) 264 { 265 266 SAVE_HINT(map, ent, ent->prev); 267 if (map->first_free == ent) { 268 map->first_free = ent->prev; 269 } 270 } 271 272 /* 273 * VM_MAP_RANGE_CHECK: check and correct range 274 * 275 * => map must at least be read locked 276 */ 277 278 #define VM_MAP_RANGE_CHECK(map, start, end) do { \ 279 if (start < vm_map_min(map)) \ 280 start = vm_map_min(map); \ 281 if (end > vm_map_max(map)) \ 282 end = vm_map_max(map); \ 283 if (start > end) \ 284 start = end; \ 285 } while (/*CONSTCOND*/ 0) 286 287 /* 288 * local prototypes 289 */ 290 291 static struct vm_map_entry * 292 uvm_mapent_alloc(struct vm_map *, int); 293 static void uvm_mapent_copy(struct vm_map_entry *, struct vm_map_entry *); 294 static void uvm_mapent_free(struct vm_map_entry *); 295 #if defined(DEBUG) 296 static void _uvm_mapent_check(const struct vm_map_entry *, int); 297 #define uvm_mapent_check(map) _uvm_mapent_check(map, __LINE__) 298 #else /* defined(DEBUG) */ 299 #define uvm_mapent_check(e) /* nothing */ 300 #endif /* defined(DEBUG) */ 301 302 static void uvm_map_entry_unwire(struct vm_map *, struct vm_map_entry *); 303 static void uvm_map_reference_amap(struct vm_map_entry *, int); 304 static int uvm_map_space_avail(vaddr_t *, vsize_t, voff_t, vsize_t, int, 305 int, struct vm_map_entry *); 306 static void uvm_map_unreference_amap(struct vm_map_entry *, int); 307 308 int _uvm_map_sanity(struct vm_map *); 309 int _uvm_tree_sanity(struct vm_map *); 310 static vsize_t uvm_rb_maxgap(const struct vm_map_entry *); 311 312 #define ROOT_ENTRY(map) ((struct vm_map_entry *)(map)->rb_tree.rbt_root) 313 #define LEFT_ENTRY(entry) ((struct vm_map_entry *)(entry)->rb_node.rb_left) 314 #define RIGHT_ENTRY(entry) ((struct vm_map_entry *)(entry)->rb_node.rb_right) 315 #define PARENT_ENTRY(map, entry) \ 316 (ROOT_ENTRY(map) == (entry) \ 317 ? NULL : (struct vm_map_entry *)RB_FATHER(&(entry)->rb_node)) 318 319 /* 320 * These get filled in if/when SYSVSHM shared memory code is loaded 321 * 322 * We do this with function pointers rather the #ifdef SYSVSHM so the 323 * SYSVSHM code can be loaded and unloaded 324 */ 325 void (*uvm_shmexit)(struct vmspace *) = NULL; 326 void (*uvm_shmfork)(struct vmspace *, struct vmspace *) = NULL; 327 328 static int 329 uvm_map_compare_nodes(void *ctx, const void *nparent, const void *nkey) 330 { 331 const struct vm_map_entry *eparent = nparent; 332 const struct vm_map_entry *ekey = nkey; 333 334 KASSERT(eparent->start < ekey->start || eparent->start >= ekey->end); 335 KASSERT(ekey->start < eparent->start || ekey->start >= eparent->end); 336 337 if (eparent->start < ekey->start) 338 return -1; 339 if (eparent->end >= ekey->start) 340 return 1; 341 return 0; 342 } 343 344 static int 345 uvm_map_compare_key(void *ctx, const void *nparent, const void *vkey) 346 { 347 const struct vm_map_entry *eparent = nparent; 348 const vaddr_t va = *(const vaddr_t *) vkey; 349 350 if (eparent->start < va) 351 return -1; 352 if (eparent->end >= va) 353 return 1; 354 return 0; 355 } 356 357 static const rb_tree_ops_t uvm_map_tree_ops = { 358 .rbto_compare_nodes = uvm_map_compare_nodes, 359 .rbto_compare_key = uvm_map_compare_key, 360 .rbto_node_offset = offsetof(struct vm_map_entry, rb_node), 361 .rbto_context = NULL 362 }; 363 364 /* 365 * uvm_rb_gap: return the gap size between our entry and next entry. 366 */ 367 static inline vsize_t 368 uvm_rb_gap(const struct vm_map_entry *entry) 369 { 370 371 KASSERT(entry->next != NULL); 372 return entry->next->start - entry->end; 373 } 374 375 static vsize_t 376 uvm_rb_maxgap(const struct vm_map_entry *entry) 377 { 378 struct vm_map_entry *child; 379 vsize_t maxgap = entry->gap; 380 381 /* 382 * We need maxgap to be the largest gap of us or any of our 383 * descendents. Since each of our children's maxgap is the 384 * cached value of their largest gap of themselves or their 385 * descendents, we can just use that value and avoid recursing 386 * down the tree to calculate it. 387 */ 388 if ((child = LEFT_ENTRY(entry)) != NULL && maxgap < child->maxgap) 389 maxgap = child->maxgap; 390 391 if ((child = RIGHT_ENTRY(entry)) != NULL && maxgap < child->maxgap) 392 maxgap = child->maxgap; 393 394 return maxgap; 395 } 396 397 static void 398 uvm_rb_fixup(struct vm_map *map, struct vm_map_entry *entry) 399 { 400 struct vm_map_entry *parent; 401 402 KASSERT(entry->gap == uvm_rb_gap(entry)); 403 entry->maxgap = uvm_rb_maxgap(entry); 404 405 while ((parent = PARENT_ENTRY(map, entry)) != NULL) { 406 struct vm_map_entry *brother; 407 vsize_t maxgap = parent->gap; 408 unsigned int which; 409 410 KDASSERT(parent->gap == uvm_rb_gap(parent)); 411 if (maxgap < entry->maxgap) 412 maxgap = entry->maxgap; 413 /* 414 * Since we work towards the root, we know entry's maxgap 415 * value is OK, but its brothers may now be out-of-date due 416 * to rebalancing. So refresh it. 417 */ 418 which = RB_POSITION(&entry->rb_node) ^ RB_DIR_OTHER; 419 brother = (struct vm_map_entry *)parent->rb_node.rb_nodes[which]; 420 if (brother != NULL) { 421 KDASSERT(brother->gap == uvm_rb_gap(brother)); 422 brother->maxgap = uvm_rb_maxgap(brother); 423 if (maxgap < brother->maxgap) 424 maxgap = brother->maxgap; 425 } 426 427 parent->maxgap = maxgap; 428 entry = parent; 429 } 430 } 431 432 static void 433 uvm_rb_insert(struct vm_map *map, struct vm_map_entry *entry) 434 { 435 struct vm_map_entry *ret __diagused; 436 437 entry->gap = entry->maxgap = uvm_rb_gap(entry); 438 if (entry->prev != &map->header) 439 entry->prev->gap = uvm_rb_gap(entry->prev); 440 441 ret = rb_tree_insert_node(&map->rb_tree, entry); 442 KASSERTMSG(ret == entry, 443 "uvm_rb_insert: map %p: duplicate entry %p", map, ret); 444 445 /* 446 * If the previous entry is not our immediate left child, then it's an 447 * ancestor and will be fixed up on the way to the root. We don't 448 * have to check entry->prev against &map->header since &map->header 449 * will never be in the tree. 450 */ 451 uvm_rb_fixup(map, 452 LEFT_ENTRY(entry) == entry->prev ? entry->prev : entry); 453 } 454 455 static void 456 uvm_rb_remove(struct vm_map *map, struct vm_map_entry *entry) 457 { 458 struct vm_map_entry *prev_parent = NULL, *next_parent = NULL; 459 460 /* 461 * If we are removing an interior node, then an adjacent node will 462 * be used to replace its position in the tree. Therefore we will 463 * need to fixup the tree starting at the parent of the replacement 464 * node. So record their parents for later use. 465 */ 466 if (entry->prev != &map->header) 467 prev_parent = PARENT_ENTRY(map, entry->prev); 468 if (entry->next != &map->header) 469 next_parent = PARENT_ENTRY(map, entry->next); 470 471 rb_tree_remove_node(&map->rb_tree, entry); 472 473 /* 474 * If the previous node has a new parent, fixup the tree starting 475 * at the previous node's old parent. 476 */ 477 if (entry->prev != &map->header) { 478 /* 479 * Update the previous entry's gap due to our absence. 480 */ 481 entry->prev->gap = uvm_rb_gap(entry->prev); 482 uvm_rb_fixup(map, entry->prev); 483 if (prev_parent != NULL 484 && prev_parent != entry 485 && prev_parent != PARENT_ENTRY(map, entry->prev)) 486 uvm_rb_fixup(map, prev_parent); 487 } 488 489 /* 490 * If the next node has a new parent, fixup the tree starting 491 * at the next node's old parent. 492 */ 493 if (entry->next != &map->header) { 494 uvm_rb_fixup(map, entry->next); 495 if (next_parent != NULL 496 && next_parent != entry 497 && next_parent != PARENT_ENTRY(map, entry->next)) 498 uvm_rb_fixup(map, next_parent); 499 } 500 } 501 502 #if defined(DEBUG) 503 int uvm_debug_check_map = 0; 504 int uvm_debug_check_rbtree = 0; 505 #define uvm_map_check(map, name) \ 506 _uvm_map_check((map), (name), __FILE__, __LINE__) 507 static void 508 _uvm_map_check(struct vm_map *map, const char *name, 509 const char *file, int line) 510 { 511 512 if ((uvm_debug_check_map && _uvm_map_sanity(map)) || 513 (uvm_debug_check_rbtree && _uvm_tree_sanity(map))) { 514 panic("uvm_map_check failed: \"%s\" map=%p (%s:%d)", 515 name, map, file, line); 516 } 517 } 518 #else /* defined(DEBUG) */ 519 #define uvm_map_check(map, name) /* nothing */ 520 #endif /* defined(DEBUG) */ 521 522 #if defined(DEBUG) || defined(DDB) 523 int 524 _uvm_map_sanity(struct vm_map *map) 525 { 526 bool first_free_found = false; 527 bool hint_found = false; 528 const struct vm_map_entry *e; 529 struct vm_map_entry *hint = map->hint; 530 531 e = &map->header; 532 for (;;) { 533 if (map->first_free == e) { 534 first_free_found = true; 535 } else if (!first_free_found && e->next->start > e->end) { 536 printf("first_free %p should be %p\n", 537 map->first_free, e); 538 return -1; 539 } 540 if (hint == e) { 541 hint_found = true; 542 } 543 544 e = e->next; 545 if (e == &map->header) { 546 break; 547 } 548 } 549 if (!first_free_found) { 550 printf("stale first_free\n"); 551 return -1; 552 } 553 if (!hint_found) { 554 printf("stale hint\n"); 555 return -1; 556 } 557 return 0; 558 } 559 560 int 561 _uvm_tree_sanity(struct vm_map *map) 562 { 563 struct vm_map_entry *tmp, *trtmp; 564 int n = 0, i = 1; 565 566 for (tmp = map->header.next; tmp != &map->header; tmp = tmp->next) { 567 if (tmp->gap != uvm_rb_gap(tmp)) { 568 printf("%d/%d gap %#lx != %#lx %s\n", 569 n + 1, map->nentries, 570 (ulong)tmp->gap, (ulong)uvm_rb_gap(tmp), 571 tmp->next == &map->header ? "(last)" : ""); 572 goto error; 573 } 574 /* 575 * If any entries are out of order, tmp->gap will be unsigned 576 * and will likely exceed the size of the map. 577 */ 578 if (tmp->gap >= vm_map_max(map) - vm_map_min(map)) { 579 printf("too large gap %zu\n", (size_t)tmp->gap); 580 goto error; 581 } 582 n++; 583 } 584 585 if (n != map->nentries) { 586 printf("nentries: %d vs %d\n", n, map->nentries); 587 goto error; 588 } 589 590 trtmp = NULL; 591 for (tmp = map->header.next; tmp != &map->header; tmp = tmp->next) { 592 if (tmp->maxgap != uvm_rb_maxgap(tmp)) { 593 printf("maxgap %#lx != %#lx\n", 594 (ulong)tmp->maxgap, 595 (ulong)uvm_rb_maxgap(tmp)); 596 goto error; 597 } 598 if (trtmp != NULL && trtmp->start >= tmp->start) { 599 printf("corrupt: 0x%"PRIxVADDR"x >= 0x%"PRIxVADDR"x\n", 600 trtmp->start, tmp->start); 601 goto error; 602 } 603 604 trtmp = tmp; 605 } 606 607 for (tmp = map->header.next; tmp != &map->header; 608 tmp = tmp->next, i++) { 609 trtmp = rb_tree_iterate(&map->rb_tree, tmp, RB_DIR_LEFT); 610 if (trtmp == NULL) 611 trtmp = &map->header; 612 if (tmp->prev != trtmp) { 613 printf("lookup: %d: %p->prev=%p: %p\n", 614 i, tmp, tmp->prev, trtmp); 615 goto error; 616 } 617 trtmp = rb_tree_iterate(&map->rb_tree, tmp, RB_DIR_RIGHT); 618 if (trtmp == NULL) 619 trtmp = &map->header; 620 if (tmp->next != trtmp) { 621 printf("lookup: %d: %p->next=%p: %p\n", 622 i, tmp, tmp->next, trtmp); 623 goto error; 624 } 625 trtmp = rb_tree_find_node(&map->rb_tree, &tmp->start); 626 if (trtmp != tmp) { 627 printf("lookup: %d: %p - %p: %p\n", i, tmp, trtmp, 628 PARENT_ENTRY(map, tmp)); 629 goto error; 630 } 631 } 632 633 return (0); 634 error: 635 return (-1); 636 } 637 #endif /* defined(DEBUG) || defined(DDB) */ 638 639 /* 640 * vm_map_lock: acquire an exclusive (write) lock on a map. 641 * 642 * => The locking protocol provides for guaranteed upgrade from shared -> 643 * exclusive by whichever thread currently has the map marked busy. 644 * See "LOCKING PROTOCOL NOTES" in uvm_map.h. This is horrible; among 645 * other problems, it defeats any fairness guarantees provided by RW 646 * locks. 647 */ 648 649 void 650 vm_map_lock(struct vm_map *map) 651 { 652 653 for (;;) { 654 rw_enter(&map->lock, RW_WRITER); 655 if (map->busy == NULL || map->busy == curlwp) { 656 break; 657 } 658 mutex_enter(&map->misc_lock); 659 rw_exit(&map->lock); 660 if (map->busy != NULL) { 661 cv_wait(&map->cv, &map->misc_lock); 662 } 663 mutex_exit(&map->misc_lock); 664 } 665 map->timestamp++; 666 } 667 668 /* 669 * vm_map_lock_try: try to lock a map, failing if it is already locked. 670 */ 671 672 bool 673 vm_map_lock_try(struct vm_map *map) 674 { 675 676 if (!rw_tryenter(&map->lock, RW_WRITER)) { 677 return false; 678 } 679 if (map->busy != NULL) { 680 rw_exit(&map->lock); 681 return false; 682 } 683 map->timestamp++; 684 return true; 685 } 686 687 /* 688 * vm_map_unlock: release an exclusive lock on a map. 689 */ 690 691 void 692 vm_map_unlock(struct vm_map *map) 693 { 694 695 KASSERT(rw_write_held(&map->lock)); 696 KASSERT(map->busy == NULL || map->busy == curlwp); 697 rw_exit(&map->lock); 698 } 699 700 /* 701 * vm_map_unbusy: mark the map as unbusy, and wake any waiters that 702 * want an exclusive lock. 703 */ 704 705 void 706 vm_map_unbusy(struct vm_map *map) 707 { 708 709 KASSERT(map->busy == curlwp); 710 711 /* 712 * Safe to clear 'busy' and 'waiters' with only a read lock held: 713 * 714 * o they can only be set with a write lock held 715 * o writers are blocked out with a read or write hold 716 * o at any time, only one thread owns the set of values 717 */ 718 mutex_enter(&map->misc_lock); 719 map->busy = NULL; 720 cv_broadcast(&map->cv); 721 mutex_exit(&map->misc_lock); 722 } 723 724 /* 725 * vm_map_lock_read: acquire a shared (read) lock on a map. 726 */ 727 728 void 729 vm_map_lock_read(struct vm_map *map) 730 { 731 732 rw_enter(&map->lock, RW_READER); 733 } 734 735 /* 736 * vm_map_unlock_read: release a shared lock on a map. 737 */ 738 739 void 740 vm_map_unlock_read(struct vm_map *map) 741 { 742 743 rw_exit(&map->lock); 744 } 745 746 /* 747 * vm_map_busy: mark a map as busy. 748 * 749 * => the caller must hold the map write locked 750 */ 751 752 void 753 vm_map_busy(struct vm_map *map) 754 { 755 756 KASSERT(rw_write_held(&map->lock)); 757 KASSERT(map->busy == NULL); 758 759 map->busy = curlwp; 760 } 761 762 /* 763 * vm_map_locked_p: return true if the map is write locked. 764 * 765 * => only for debug purposes like KASSERTs. 766 * => should not be used to verify that a map is not locked. 767 */ 768 769 bool 770 vm_map_locked_p(struct vm_map *map) 771 { 772 773 return rw_write_held(&map->lock); 774 } 775 776 /* 777 * uvm_mapent_alloc: allocate a map entry 778 */ 779 780 static struct vm_map_entry * 781 uvm_mapent_alloc(struct vm_map *map, int flags) 782 { 783 struct vm_map_entry *me; 784 int pflags = (flags & UVM_FLAG_NOWAIT) ? PR_NOWAIT : PR_WAITOK; 785 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 786 787 me = pool_cache_get(&uvm_map_entry_cache, pflags); 788 if (__predict_false(me == NULL)) { 789 return NULL; 790 } 791 me->flags = 0; 792 793 UVMHIST_LOG(maphist, "<- new entry=%#jx [kentry=%jd]", (uintptr_t)me, 794 (map == kernel_map), 0, 0); 795 return me; 796 } 797 798 /* 799 * uvm_mapent_free: free map entry 800 */ 801 802 static void 803 uvm_mapent_free(struct vm_map_entry *me) 804 { 805 UVMHIST_FUNC(__func__); 806 UVMHIST_CALLARGS(maphist,"<- freeing map entry=%#jx [flags=%#jx]", 807 (uintptr_t)me, me->flags, 0, 0); 808 pool_cache_put(&uvm_map_entry_cache, me); 809 } 810 811 /* 812 * uvm_mapent_copy: copy a map entry, preserving flags 813 */ 814 815 static inline void 816 uvm_mapent_copy(struct vm_map_entry *src, struct vm_map_entry *dst) 817 { 818 819 memcpy(dst, src, sizeof(*dst)); 820 dst->flags = 0; 821 } 822 823 #if defined(DEBUG) 824 static void 825 _uvm_mapent_check(const struct vm_map_entry *entry, int line) 826 { 827 828 if (entry->start >= entry->end) { 829 goto bad; 830 } 831 if (UVM_ET_ISOBJ(entry)) { 832 if (entry->object.uvm_obj == NULL) { 833 goto bad; 834 } 835 } else if (UVM_ET_ISSUBMAP(entry)) { 836 if (entry->object.sub_map == NULL) { 837 goto bad; 838 } 839 } else { 840 if (entry->object.uvm_obj != NULL || 841 entry->object.sub_map != NULL) { 842 goto bad; 843 } 844 } 845 if (!UVM_ET_ISOBJ(entry)) { 846 if (entry->offset != 0) { 847 goto bad; 848 } 849 } 850 851 return; 852 853 bad: 854 panic("%s: bad entry %p, line %d", __func__, entry, line); 855 } 856 #endif /* defined(DEBUG) */ 857 858 /* 859 * uvm_map_entry_unwire: unwire a map entry 860 * 861 * => map should be locked by caller 862 */ 863 864 static inline void 865 uvm_map_entry_unwire(struct vm_map *map, struct vm_map_entry *entry) 866 { 867 868 entry->wired_count = 0; 869 uvm_fault_unwire_locked(map, entry->start, entry->end); 870 } 871 872 873 /* 874 * wrapper for calling amap_ref() 875 */ 876 static inline void 877 uvm_map_reference_amap(struct vm_map_entry *entry, int flags) 878 { 879 880 amap_ref(entry->aref.ar_amap, entry->aref.ar_pageoff, 881 (entry->end - entry->start) >> PAGE_SHIFT, flags); 882 } 883 884 885 /* 886 * wrapper for calling amap_unref() 887 */ 888 static inline void 889 uvm_map_unreference_amap(struct vm_map_entry *entry, int flags) 890 { 891 892 amap_unref(entry->aref.ar_amap, entry->aref.ar_pageoff, 893 (entry->end - entry->start) >> PAGE_SHIFT, flags); 894 } 895 896 897 /* 898 * uvm_map_init: init mapping system at boot time. 899 */ 900 901 void 902 uvm_map_init(void) 903 { 904 /* 905 * first, init logging system. 906 */ 907 908 UVMHIST_FUNC(__func__); 909 UVMHIST_LINK_STATIC(maphist); 910 UVMHIST_LINK_STATIC(pdhist); 911 UVMHIST_CALLED(maphist); 912 UVMHIST_LOG(maphist,"<starting uvm map system>", 0, 0, 0, 0); 913 914 /* 915 * initialize the global lock for kernel map entry. 916 */ 917 918 mutex_init(&uvm_kentry_lock, MUTEX_DRIVER, IPL_VM); 919 } 920 921 /* 922 * uvm_map_init_caches: init mapping system caches. 923 */ 924 void 925 uvm_map_init_caches(void) 926 { 927 /* 928 * initialize caches. 929 */ 930 931 pool_cache_bootstrap(&uvm_map_entry_cache, sizeof(struct vm_map_entry), 932 coherency_unit, 0, PR_LARGECACHE, "vmmpepl", NULL, IPL_NONE, NULL, 933 NULL, NULL); 934 pool_cache_bootstrap(&uvm_vmspace_cache, sizeof(struct vmspace), 935 0, 0, 0, "vmsppl", NULL, IPL_NONE, NULL, NULL, NULL); 936 } 937 938 /* 939 * clippers 940 */ 941 942 /* 943 * uvm_mapent_splitadj: adjust map entries for splitting, after uvm_mapent_copy. 944 */ 945 946 static void 947 uvm_mapent_splitadj(struct vm_map_entry *entry1, struct vm_map_entry *entry2, 948 vaddr_t splitat) 949 { 950 vaddr_t adj; 951 952 KASSERT(entry1->start < splitat); 953 KASSERT(splitat < entry1->end); 954 955 adj = splitat - entry1->start; 956 entry1->end = entry2->start = splitat; 957 958 if (entry1->aref.ar_amap) { 959 amap_splitref(&entry1->aref, &entry2->aref, adj); 960 } 961 if (UVM_ET_ISSUBMAP(entry1)) { 962 /* ... unlikely to happen, but play it safe */ 963 uvm_map_reference(entry1->object.sub_map); 964 } else if (UVM_ET_ISOBJ(entry1)) { 965 KASSERT(entry1->object.uvm_obj != NULL); /* suppress coverity */ 966 entry2->offset += adj; 967 if (entry1->object.uvm_obj->pgops && 968 entry1->object.uvm_obj->pgops->pgo_reference) 969 entry1->object.uvm_obj->pgops->pgo_reference( 970 entry1->object.uvm_obj); 971 } 972 } 973 974 /* 975 * uvm_map_clip_start: ensure that the entry begins at or after 976 * the starting address, if it doesn't we split the entry. 977 * 978 * => caller should use UVM_MAP_CLIP_START macro rather than calling 979 * this directly 980 * => map must be locked by caller 981 */ 982 983 void 984 uvm_map_clip_start(struct vm_map *map, struct vm_map_entry *entry, 985 vaddr_t start) 986 { 987 struct vm_map_entry *new_entry; 988 989 /* uvm_map_simplify_entry(map, entry); */ /* XXX */ 990 991 uvm_map_check(map, "clip_start entry"); 992 uvm_mapent_check(entry); 993 994 /* 995 * Split off the front portion. note that we must insert the new 996 * entry BEFORE this one, so that this entry has the specified 997 * starting address. 998 */ 999 new_entry = uvm_mapent_alloc(map, 0); 1000 uvm_mapent_copy(entry, new_entry); /* entry -> new_entry */ 1001 uvm_mapent_splitadj(new_entry, entry, start); 1002 uvm_map_entry_link(map, entry->prev, new_entry); 1003 1004 uvm_map_check(map, "clip_start leave"); 1005 } 1006 1007 /* 1008 * uvm_map_clip_end: ensure that the entry ends at or before 1009 * the ending address, if it does't we split the reference 1010 * 1011 * => caller should use UVM_MAP_CLIP_END macro rather than calling 1012 * this directly 1013 * => map must be locked by caller 1014 */ 1015 1016 void 1017 uvm_map_clip_end(struct vm_map *map, struct vm_map_entry *entry, vaddr_t end) 1018 { 1019 struct vm_map_entry *new_entry; 1020 1021 uvm_map_check(map, "clip_end entry"); 1022 uvm_mapent_check(entry); 1023 1024 /* 1025 * Create a new entry and insert it 1026 * AFTER the specified entry 1027 */ 1028 new_entry = uvm_mapent_alloc(map, 0); 1029 uvm_mapent_copy(entry, new_entry); /* entry -> new_entry */ 1030 uvm_mapent_splitadj(entry, new_entry, end); 1031 uvm_map_entry_link(map, entry, new_entry); 1032 1033 uvm_map_check(map, "clip_end leave"); 1034 } 1035 1036 /* 1037 * M A P - m a i n e n t r y p o i n t 1038 */ 1039 /* 1040 * uvm_map: establish a valid mapping in a map 1041 * 1042 * => assume startp is page aligned. 1043 * => assume size is a multiple of PAGE_SIZE. 1044 * => assume sys_mmap provides enough of a "hint" to have us skip 1045 * over text/data/bss area. 1046 * => map must be unlocked (we will lock it) 1047 * => <uobj,uoffset> value meanings (4 cases): 1048 * [1] <NULL,uoffset> == uoffset is a hint for PMAP_PREFER 1049 * [2] <NULL,UVM_UNKNOWN_OFFSET> == don't PMAP_PREFER 1050 * [3] <uobj,uoffset> == normal mapping 1051 * [4] <uobj,UVM_UNKNOWN_OFFSET> == uvm_map finds offset based on VA 1052 * 1053 * case [4] is for kernel mappings where we don't know the offset until 1054 * we've found a virtual address. note that kernel object offsets are 1055 * always relative to vm_map_min(kernel_map). 1056 * 1057 * => if `align' is non-zero, we align the virtual address to the specified 1058 * alignment. 1059 * this is provided as a mechanism for large pages. 1060 * 1061 * => XXXCDC: need way to map in external amap? 1062 */ 1063 1064 int 1065 uvm_map(struct vm_map *map, vaddr_t *startp /* IN/OUT */, vsize_t size, 1066 struct uvm_object *uobj, voff_t uoffset, vsize_t align, uvm_flag_t flags) 1067 { 1068 struct uvm_map_args args; 1069 struct vm_map_entry *new_entry; 1070 int error; 1071 1072 KASSERT((size & PAGE_MASK) == 0); 1073 KASSERT((flags & UVM_FLAG_FIXED) == 0 || align == 0); 1074 1075 /* 1076 * for pager_map, allocate the new entry first to avoid sleeping 1077 * for memory while we have the map locked. 1078 */ 1079 1080 new_entry = NULL; 1081 if (map == pager_map) { 1082 new_entry = uvm_mapent_alloc(map, (flags & UVM_FLAG_NOWAIT)); 1083 if (__predict_false(new_entry == NULL)) 1084 return ENOMEM; 1085 } 1086 if (map == pager_map) 1087 flags |= UVM_FLAG_NOMERGE; 1088 1089 error = uvm_map_prepare(map, *startp, size, uobj, uoffset, align, 1090 flags, &args); 1091 if (!error) { 1092 error = uvm_map_enter(map, &args, new_entry); 1093 *startp = args.uma_start; 1094 } else if (new_entry) { 1095 uvm_mapent_free(new_entry); 1096 } 1097 1098 #if defined(DEBUG) 1099 if (!error && VM_MAP_IS_KERNEL(map) && (flags & UVM_FLAG_NOWAIT) == 0) { 1100 uvm_km_check_empty(map, *startp, *startp + size); 1101 } 1102 #endif /* defined(DEBUG) */ 1103 1104 return error; 1105 } 1106 1107 /* 1108 * uvm_map_prepare: 1109 * 1110 * called with map unlocked. 1111 * on success, returns the map locked. 1112 */ 1113 1114 int 1115 uvm_map_prepare(struct vm_map *map, vaddr_t start, vsize_t size, 1116 struct uvm_object *uobj, voff_t uoffset, vsize_t align, uvm_flag_t flags, 1117 struct uvm_map_args *args) 1118 { 1119 struct vm_map_entry *prev_entry; 1120 vm_prot_t prot = UVM_PROTECTION(flags); 1121 vm_prot_t maxprot = UVM_MAXPROTECTION(flags); 1122 1123 UVMHIST_FUNC(__func__); 1124 UVMHIST_CALLARGS(maphist, "(map=%#jx, start=%#jx, size=%jx, flags=%#jx)", 1125 (uintptr_t)map, start, size, flags); 1126 UVMHIST_LOG(maphist, " uobj/offset %#jx/%jd", (uintptr_t)uobj, 1127 uoffset,0,0); 1128 1129 /* 1130 * detect a popular device driver bug. 1131 */ 1132 1133 KASSERT(doing_shutdown || curlwp != NULL); 1134 1135 /* 1136 * zero-sized mapping doesn't make any sense. 1137 */ 1138 KASSERT(size > 0); 1139 1140 KASSERT((~flags & (UVM_FLAG_NOWAIT | UVM_FLAG_WAITVA)) != 0); 1141 1142 uvm_map_check(map, "map entry"); 1143 1144 /* 1145 * check sanity of protection code 1146 */ 1147 1148 if ((prot & maxprot) != prot) { 1149 UVMHIST_LOG(maphist, "<- prot. failure: prot=%#jx, max=%#jx", 1150 prot, maxprot,0,0); 1151 return EACCES; 1152 } 1153 1154 /* 1155 * figure out where to put new VM range 1156 */ 1157 retry: 1158 if (vm_map_lock_try(map) == false) { 1159 if ((flags & UVM_FLAG_TRYLOCK) != 0) { 1160 return EAGAIN; 1161 } 1162 vm_map_lock(map); /* could sleep here */ 1163 } 1164 if (flags & UVM_FLAG_UNMAP) { 1165 KASSERT(flags & UVM_FLAG_FIXED); 1166 KASSERT((flags & UVM_FLAG_NOWAIT) == 0); 1167 1168 /* 1169 * Set prev_entry to what it will need to be after any existing 1170 * entries are removed later in uvm_map_enter(). 1171 */ 1172 1173 if (uvm_map_lookup_entry(map, start, &prev_entry)) { 1174 if (start == prev_entry->start) 1175 prev_entry = prev_entry->prev; 1176 else 1177 UVM_MAP_CLIP_END(map, prev_entry, start); 1178 SAVE_HINT(map, map->hint, prev_entry); 1179 } 1180 } else { 1181 prev_entry = uvm_map_findspace(map, start, size, &start, 1182 uobj, uoffset, align, flags); 1183 } 1184 if (prev_entry == NULL) { 1185 unsigned int timestamp; 1186 1187 timestamp = map->timestamp; 1188 UVMHIST_LOG(maphist,"waiting va timestamp=%#jx", 1189 timestamp,0,0,0); 1190 map->flags |= VM_MAP_WANTVA; 1191 vm_map_unlock(map); 1192 1193 /* 1194 * try to reclaim kva and wait until someone does unmap. 1195 * fragile locking here, so we awaken every second to 1196 * recheck the condition. 1197 */ 1198 1199 mutex_enter(&map->misc_lock); 1200 while ((map->flags & VM_MAP_WANTVA) != 0 && 1201 map->timestamp == timestamp) { 1202 if ((flags & UVM_FLAG_WAITVA) == 0) { 1203 mutex_exit(&map->misc_lock); 1204 UVMHIST_LOG(maphist, 1205 "<- uvm_map_findspace failed!", 0,0,0,0); 1206 return ENOMEM; 1207 } else { 1208 cv_timedwait(&map->cv, &map->misc_lock, hz); 1209 } 1210 } 1211 mutex_exit(&map->misc_lock); 1212 goto retry; 1213 } 1214 1215 #ifdef PMAP_GROWKERNEL 1216 /* 1217 * If the kernel pmap can't map the requested space, 1218 * then allocate more resources for it. 1219 */ 1220 if (map == kernel_map && uvm_maxkaddr < (start + size)) 1221 uvm_maxkaddr = pmap_growkernel(start + size); 1222 #endif 1223 1224 UVMMAP_EVCNT_INCR(map_call); 1225 1226 /* 1227 * if uobj is null, then uoffset is either a VAC hint for PMAP_PREFER 1228 * [typically from uvm_map_reserve] or it is UVM_UNKNOWN_OFFSET. in 1229 * either case we want to zero it before storing it in the map entry 1230 * (because it looks strange and confusing when debugging...) 1231 * 1232 * if uobj is not null 1233 * if uoffset is not UVM_UNKNOWN_OFFSET then we have a normal mapping 1234 * and we do not need to change uoffset. 1235 * if uoffset is UVM_UNKNOWN_OFFSET then we need to find the offset 1236 * now (based on the starting address of the map). this case is 1237 * for kernel object mappings where we don't know the offset until 1238 * the virtual address is found (with uvm_map_findspace). the 1239 * offset is the distance we are from the start of the map. 1240 */ 1241 1242 if (uobj == NULL) { 1243 uoffset = 0; 1244 } else { 1245 if (uoffset == UVM_UNKNOWN_OFFSET) { 1246 KASSERT(UVM_OBJ_IS_KERN_OBJECT(uobj)); 1247 uoffset = start - vm_map_min(kernel_map); 1248 } 1249 } 1250 1251 args->uma_flags = flags; 1252 args->uma_prev = prev_entry; 1253 args->uma_start = start; 1254 args->uma_size = size; 1255 args->uma_uobj = uobj; 1256 args->uma_uoffset = uoffset; 1257 1258 UVMHIST_LOG(maphist, "<- done!", 0,0,0,0); 1259 return 0; 1260 } 1261 1262 /* 1263 * uvm_map_enter: 1264 * 1265 * called with map locked. 1266 * unlock the map before returning. 1267 */ 1268 1269 int 1270 uvm_map_enter(struct vm_map *map, const struct uvm_map_args *args, 1271 struct vm_map_entry *new_entry) 1272 { 1273 struct vm_map_entry *prev_entry = args->uma_prev; 1274 struct vm_map_entry *dead = NULL, *dead_entries = NULL; 1275 1276 const uvm_flag_t flags = args->uma_flags; 1277 const vm_prot_t prot = UVM_PROTECTION(flags); 1278 const vm_prot_t maxprot = UVM_MAXPROTECTION(flags); 1279 const vm_inherit_t inherit = UVM_INHERIT(flags); 1280 const int amapwaitflag = (flags & UVM_FLAG_NOWAIT) ? 1281 AMAP_EXTEND_NOWAIT : 0; 1282 const int advice = UVM_ADVICE(flags); 1283 1284 vaddr_t start = args->uma_start; 1285 vsize_t size = args->uma_size; 1286 struct uvm_object *uobj = args->uma_uobj; 1287 voff_t uoffset = args->uma_uoffset; 1288 1289 const int kmap = (vm_map_pmap(map) == pmap_kernel()); 1290 int merged = 0; 1291 int error; 1292 int newetype; 1293 1294 UVMHIST_FUNC(__func__); 1295 UVMHIST_CALLARGS(maphist, "(map=%#jx, start=%#jx, size=%ju, flags=%#jx)", 1296 (uintptr_t)map, start, size, flags); 1297 UVMHIST_LOG(maphist, " uobj/offset %#jx/%jd", (uintptr_t)uobj, 1298 uoffset,0,0); 1299 1300 KASSERT(map->hint == prev_entry); /* bimerge case assumes this */ 1301 KASSERT(vm_map_locked_p(map)); 1302 KASSERT((flags & (UVM_FLAG_NOWAIT | UVM_FLAG_UNMAP)) != 1303 (UVM_FLAG_NOWAIT | UVM_FLAG_UNMAP)); 1304 1305 if (uobj) 1306 newetype = UVM_ET_OBJ; 1307 else 1308 newetype = 0; 1309 1310 if (flags & UVM_FLAG_COPYONW) { 1311 newetype |= UVM_ET_COPYONWRITE; 1312 if ((flags & UVM_FLAG_OVERLAY) == 0) 1313 newetype |= UVM_ET_NEEDSCOPY; 1314 } 1315 1316 /* 1317 * For mappings with unmap, remove any old entries now. Adding the new 1318 * entry cannot fail because that can only happen if UVM_FLAG_NOWAIT 1319 * is set, and we do not support nowait and unmap together. 1320 */ 1321 1322 if (flags & UVM_FLAG_UNMAP) { 1323 KASSERT(flags & UVM_FLAG_FIXED); 1324 uvm_unmap_remove(map, start, start + size, &dead_entries, 0); 1325 #ifdef DEBUG 1326 struct vm_map_entry *tmp_entry __diagused; 1327 bool rv __diagused; 1328 1329 rv = uvm_map_lookup_entry(map, start, &tmp_entry); 1330 KASSERT(!rv); 1331 KASSERTMSG(prev_entry == tmp_entry, 1332 "args %p prev_entry %p tmp_entry %p", 1333 args, prev_entry, tmp_entry); 1334 #endif 1335 SAVE_HINT(map, map->hint, prev_entry); 1336 } 1337 1338 /* 1339 * try and insert in map by extending previous entry, if possible. 1340 * XXX: we don't try and pull back the next entry. might be useful 1341 * for a stack, but we are currently allocating our stack in advance. 1342 */ 1343 1344 if (flags & UVM_FLAG_NOMERGE) 1345 goto nomerge; 1346 1347 if (prev_entry->end == start && 1348 prev_entry != &map->header && 1349 UVM_ET_ISCOMPATIBLE(prev_entry, newetype, uobj, 0, 1350 prot, maxprot, inherit, advice, 0)) { 1351 1352 if (uobj && prev_entry->offset + 1353 (prev_entry->end - prev_entry->start) != uoffset) 1354 goto forwardmerge; 1355 1356 /* 1357 * can't extend a shared amap. note: no need to lock amap to 1358 * look at refs since we don't care about its exact value. 1359 * if it is one (i.e. we have only reference) it will stay there 1360 */ 1361 1362 if (prev_entry->aref.ar_amap && 1363 amap_refs(prev_entry->aref.ar_amap) != 1) { 1364 goto forwardmerge; 1365 } 1366 1367 if (prev_entry->aref.ar_amap) { 1368 error = amap_extend(prev_entry, size, 1369 amapwaitflag | AMAP_EXTEND_FORWARDS); 1370 if (error) 1371 goto nomerge; 1372 } 1373 1374 if (kmap) { 1375 UVMMAP_EVCNT_INCR(kbackmerge); 1376 } else { 1377 UVMMAP_EVCNT_INCR(ubackmerge); 1378 } 1379 UVMHIST_LOG(maphist," starting back merge", 0, 0, 0, 0); 1380 1381 /* 1382 * drop our reference to uobj since we are extending a reference 1383 * that we already have (the ref count can not drop to zero). 1384 */ 1385 1386 if (uobj && uobj->pgops->pgo_detach) 1387 uobj->pgops->pgo_detach(uobj); 1388 1389 /* 1390 * Now that we've merged the entries, note that we've grown 1391 * and our gap has shrunk. Then fix the tree. 1392 */ 1393 prev_entry->end += size; 1394 prev_entry->gap -= size; 1395 uvm_rb_fixup(map, prev_entry); 1396 1397 uvm_map_check(map, "map backmerged"); 1398 1399 UVMHIST_LOG(maphist,"<- done (via backmerge)!", 0, 0, 0, 0); 1400 merged++; 1401 } 1402 1403 forwardmerge: 1404 if (prev_entry->next->start == (start + size) && 1405 prev_entry->next != &map->header && 1406 UVM_ET_ISCOMPATIBLE(prev_entry->next, newetype, uobj, 0, 1407 prot, maxprot, inherit, advice, 0)) { 1408 1409 if (uobj && prev_entry->next->offset != uoffset + size) 1410 goto nomerge; 1411 1412 /* 1413 * can't extend a shared amap. note: no need to lock amap to 1414 * look at refs since we don't care about its exact value. 1415 * if it is one (i.e. we have only reference) it will stay there. 1416 * 1417 * note that we also can't merge two amaps, so if we 1418 * merged with the previous entry which has an amap, 1419 * and the next entry also has an amap, we give up. 1420 * 1421 * Interesting cases: 1422 * amap, new, amap -> give up second merge (single fwd extend) 1423 * amap, new, none -> double forward extend (extend again here) 1424 * none, new, amap -> double backward extend (done here) 1425 * uobj, new, amap -> single backward extend (done here) 1426 * 1427 * XXX should we attempt to deal with someone refilling 1428 * the deallocated region between two entries that are 1429 * backed by the same amap (ie, arefs is 2, "prev" and 1430 * "next" refer to it, and adding this allocation will 1431 * close the hole, thus restoring arefs to 1 and 1432 * deallocating the "next" vm_map_entry)? -- @@@ 1433 */ 1434 1435 if (prev_entry->next->aref.ar_amap && 1436 (amap_refs(prev_entry->next->aref.ar_amap) != 1 || 1437 (merged && prev_entry->aref.ar_amap))) { 1438 goto nomerge; 1439 } 1440 1441 if (merged) { 1442 /* 1443 * Try to extend the amap of the previous entry to 1444 * cover the next entry as well. If it doesn't work 1445 * just skip on, don't actually give up, since we've 1446 * already completed the back merge. 1447 */ 1448 if (prev_entry->aref.ar_amap) { 1449 if (amap_extend(prev_entry, 1450 prev_entry->next->end - 1451 prev_entry->next->start, 1452 amapwaitflag | AMAP_EXTEND_FORWARDS)) 1453 goto nomerge; 1454 } 1455 1456 /* 1457 * Try to extend the amap of the *next* entry 1458 * back to cover the new allocation *and* the 1459 * previous entry as well (the previous merge 1460 * didn't have an amap already otherwise we 1461 * wouldn't be checking here for an amap). If 1462 * it doesn't work just skip on, again, don't 1463 * actually give up, since we've already 1464 * completed the back merge. 1465 */ 1466 else if (prev_entry->next->aref.ar_amap) { 1467 if (amap_extend(prev_entry->next, 1468 prev_entry->end - 1469 prev_entry->start, 1470 amapwaitflag | AMAP_EXTEND_BACKWARDS)) 1471 goto nomerge; 1472 } 1473 } else { 1474 /* 1475 * Pull the next entry's amap backwards to cover this 1476 * new allocation. 1477 */ 1478 if (prev_entry->next->aref.ar_amap) { 1479 error = amap_extend(prev_entry->next, size, 1480 amapwaitflag | AMAP_EXTEND_BACKWARDS); 1481 if (error) 1482 goto nomerge; 1483 } 1484 } 1485 1486 if (merged) { 1487 if (kmap) { 1488 UVMMAP_EVCNT_DECR(kbackmerge); 1489 UVMMAP_EVCNT_INCR(kbimerge); 1490 } else { 1491 UVMMAP_EVCNT_DECR(ubackmerge); 1492 UVMMAP_EVCNT_INCR(ubimerge); 1493 } 1494 } else { 1495 if (kmap) { 1496 UVMMAP_EVCNT_INCR(kforwmerge); 1497 } else { 1498 UVMMAP_EVCNT_INCR(uforwmerge); 1499 } 1500 } 1501 UVMHIST_LOG(maphist," starting forward merge", 0, 0, 0, 0); 1502 1503 /* 1504 * drop our reference to uobj since we are extending a reference 1505 * that we already have (the ref count can not drop to zero). 1506 */ 1507 if (uobj && uobj->pgops->pgo_detach) 1508 uobj->pgops->pgo_detach(uobj); 1509 1510 if (merged) { 1511 dead = prev_entry->next; 1512 prev_entry->end = dead->end; 1513 uvm_map_entry_unlink(map, dead); 1514 if (dead->aref.ar_amap != NULL) { 1515 prev_entry->aref = dead->aref; 1516 dead->aref.ar_amap = NULL; 1517 } 1518 } else { 1519 prev_entry->next->start -= size; 1520 if (prev_entry != &map->header) { 1521 prev_entry->gap -= size; 1522 KASSERT(prev_entry->gap == uvm_rb_gap(prev_entry)); 1523 uvm_rb_fixup(map, prev_entry); 1524 } 1525 if (uobj) 1526 prev_entry->next->offset = uoffset; 1527 } 1528 1529 uvm_map_check(map, "map forwardmerged"); 1530 1531 UVMHIST_LOG(maphist,"<- done forwardmerge", 0, 0, 0, 0); 1532 merged++; 1533 } 1534 1535 nomerge: 1536 if (!merged) { 1537 UVMHIST_LOG(maphist," allocating new map entry", 0, 0, 0, 0); 1538 if (kmap) { 1539 UVMMAP_EVCNT_INCR(knomerge); 1540 } else { 1541 UVMMAP_EVCNT_INCR(unomerge); 1542 } 1543 1544 /* 1545 * allocate new entry and link it in. 1546 */ 1547 1548 if (new_entry == NULL) { 1549 new_entry = uvm_mapent_alloc(map, 1550 (flags & UVM_FLAG_NOWAIT)); 1551 if (__predict_false(new_entry == NULL)) { 1552 error = ENOMEM; 1553 goto done; 1554 } 1555 } 1556 new_entry->start = start; 1557 new_entry->end = new_entry->start + size; 1558 new_entry->object.uvm_obj = uobj; 1559 new_entry->offset = uoffset; 1560 1561 new_entry->etype = newetype; 1562 1563 if (flags & UVM_FLAG_NOMERGE) { 1564 new_entry->flags |= UVM_MAP_NOMERGE; 1565 } 1566 1567 new_entry->protection = prot; 1568 new_entry->max_protection = maxprot; 1569 new_entry->inheritance = inherit; 1570 new_entry->wired_count = 0; 1571 new_entry->advice = advice; 1572 if (flags & UVM_FLAG_OVERLAY) { 1573 1574 /* 1575 * to_add: for BSS we overallocate a little since we 1576 * are likely to extend 1577 */ 1578 1579 vaddr_t to_add = (flags & UVM_FLAG_AMAPPAD) ? 1580 UVM_AMAP_CHUNK << PAGE_SHIFT : 0; 1581 struct vm_amap *amap = amap_alloc(size, to_add, 1582 (flags & UVM_FLAG_NOWAIT)); 1583 if (__predict_false(amap == NULL)) { 1584 error = ENOMEM; 1585 goto done; 1586 } 1587 new_entry->aref.ar_pageoff = 0; 1588 new_entry->aref.ar_amap = amap; 1589 } else { 1590 new_entry->aref.ar_pageoff = 0; 1591 new_entry->aref.ar_amap = NULL; 1592 } 1593 uvm_map_entry_link(map, prev_entry, new_entry); 1594 1595 /* 1596 * Update the free space hint 1597 */ 1598 1599 if ((map->first_free == prev_entry) && 1600 (prev_entry->end >= new_entry->start)) 1601 map->first_free = new_entry; 1602 1603 new_entry = NULL; 1604 } 1605 1606 map->size += size; 1607 1608 UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0); 1609 1610 error = 0; 1611 1612 done: 1613 vm_map_unlock(map); 1614 1615 if (new_entry) { 1616 uvm_mapent_free(new_entry); 1617 } 1618 if (dead) { 1619 KDASSERT(merged); 1620 uvm_mapent_free(dead); 1621 } 1622 if (dead_entries) 1623 uvm_unmap_detach(dead_entries, 0); 1624 1625 return error; 1626 } 1627 1628 /* 1629 * uvm_map_lookup_entry_bytree: lookup an entry in tree 1630 */ 1631 1632 static inline bool 1633 uvm_map_lookup_entry_bytree(struct vm_map *map, vaddr_t address, 1634 struct vm_map_entry **entry /* OUT */) 1635 { 1636 struct vm_map_entry *prev = &map->header; 1637 struct vm_map_entry *cur = ROOT_ENTRY(map); 1638 1639 while (cur) { 1640 UVMMAP_EVCNT_INCR(mlk_treeloop); 1641 if (address >= cur->start) { 1642 if (address < cur->end) { 1643 *entry = cur; 1644 return true; 1645 } 1646 prev = cur; 1647 cur = RIGHT_ENTRY(cur); 1648 } else 1649 cur = LEFT_ENTRY(cur); 1650 } 1651 *entry = prev; 1652 return false; 1653 } 1654 1655 /* 1656 * uvm_map_lookup_entry: find map entry at or before an address 1657 * 1658 * => map must at least be read-locked by caller 1659 * => entry is returned in "entry" 1660 * => return value is true if address is in the returned entry 1661 */ 1662 1663 bool 1664 uvm_map_lookup_entry(struct vm_map *map, vaddr_t address, 1665 struct vm_map_entry **entry /* OUT */) 1666 { 1667 struct vm_map_entry *cur; 1668 UVMHIST_FUNC(__func__); 1669 UVMHIST_CALLARGS(maphist,"(map=%#jx,addr=%#jx,ent=%#jx)", 1670 (uintptr_t)map, address, (uintptr_t)entry, 0); 1671 1672 /* 1673 * make a quick check to see if we are already looking at 1674 * the entry we want (which is usually the case). note also 1675 * that we don't need to save the hint here... it is the 1676 * same hint (unless we are at the header, in which case the 1677 * hint didn't buy us anything anyway). 1678 */ 1679 1680 cur = map->hint; 1681 UVMMAP_EVCNT_INCR(mlk_call); 1682 if (cur != &map->header && 1683 address >= cur->start && cur->end > address) { 1684 UVMMAP_EVCNT_INCR(mlk_hint); 1685 *entry = cur; 1686 UVMHIST_LOG(maphist,"<- got it via hint (%#jx)", 1687 (uintptr_t)cur, 0, 0, 0); 1688 uvm_mapent_check(*entry); 1689 return (true); 1690 } 1691 uvm_map_check(map, __func__); 1692 1693 /* 1694 * lookup in the tree. 1695 */ 1696 1697 UVMMAP_EVCNT_INCR(mlk_tree); 1698 if (__predict_true(uvm_map_lookup_entry_bytree(map, address, entry))) { 1699 SAVE_HINT(map, map->hint, *entry); 1700 UVMHIST_LOG(maphist,"<- search got it (%#jx)", 1701 (uintptr_t)cur, 0, 0, 0); 1702 KDASSERT((*entry)->start <= address); 1703 KDASSERT(address < (*entry)->end); 1704 uvm_mapent_check(*entry); 1705 return (true); 1706 } 1707 1708 SAVE_HINT(map, map->hint, *entry); 1709 UVMHIST_LOG(maphist,"<- failed!",0,0,0,0); 1710 KDASSERT((*entry) == &map->header || (*entry)->end <= address); 1711 KDASSERT((*entry)->next == &map->header || 1712 address < (*entry)->next->start); 1713 return (false); 1714 } 1715 1716 /* 1717 * See if the range between start and start + length fits in the gap 1718 * entry->next->start and entry->end. Returns 1 if fits, 0 if doesn't 1719 * fit, and -1 address wraps around. 1720 */ 1721 static int 1722 uvm_map_space_avail(vaddr_t *start, vsize_t length, voff_t uoffset, 1723 vsize_t align, int flags, int topdown, struct vm_map_entry *entry) 1724 { 1725 vaddr_t end; 1726 1727 #ifdef PMAP_PREFER 1728 /* 1729 * push start address forward as needed to avoid VAC alias problems. 1730 * we only do this if a valid offset is specified. 1731 */ 1732 1733 if (uoffset != UVM_UNKNOWN_OFFSET) 1734 PMAP_PREFER(uoffset, start, length, topdown); 1735 #endif 1736 if ((flags & UVM_FLAG_COLORMATCH) != 0) { 1737 KASSERT(align < uvmexp.ncolors); 1738 if (uvmexp.ncolors > 1) { 1739 const u_int colormask = uvmexp.colormask; 1740 const u_int colorsize = colormask + 1; 1741 vaddr_t hint = atop(*start); 1742 const u_int color = hint & colormask; 1743 if (color != align) { 1744 hint -= color; /* adjust to color boundary */ 1745 KASSERT((hint & colormask) == 0); 1746 if (topdown) { 1747 if (align > color) 1748 hint -= colorsize; 1749 } else { 1750 if (align < color) 1751 hint += colorsize; 1752 } 1753 *start = ptoa(hint + align); /* adjust to color */ 1754 } 1755 } 1756 } else { 1757 KASSERT(powerof2(align)); 1758 uvm_map_align_va(start, align, topdown); 1759 /* 1760 * XXX Should we PMAP_PREFER() here again? 1761 * eh...i think we're okay 1762 */ 1763 } 1764 1765 /* 1766 * Find the end of the proposed new region. Be sure we didn't 1767 * wrap around the address; if so, we lose. Otherwise, if the 1768 * proposed new region fits before the next entry, we win. 1769 */ 1770 1771 end = *start + length; 1772 if (end < *start) 1773 return (-1); 1774 1775 if (entry->next->start >= end && *start >= entry->end) 1776 return (1); 1777 1778 return (0); 1779 } 1780 1781 static void 1782 uvm_findspace_invariants(struct vm_map *map, vaddr_t orig_hint, vaddr_t length, 1783 struct uvm_object *uobj, voff_t uoffset, vsize_t align, int flags, 1784 vaddr_t hint, struct vm_map_entry *entry, int line) 1785 { 1786 const int topdown = map->flags & VM_MAP_TOPDOWN; 1787 1788 KASSERTMSG( topdown || hint >= orig_hint, 1789 "map=%p hint=%#"PRIxVADDR" orig_hint=%#"PRIxVADDR 1790 " length=%#"PRIxVSIZE" uobj=%p uoffset=%#llx align=%"PRIxVSIZE 1791 " flags=%#x entry=%p (uvm_map_findspace line %d)", 1792 map, hint, orig_hint, 1793 length, uobj, (unsigned long long)uoffset, align, 1794 flags, entry, line); 1795 #ifndef __sh3__ /* XXXRO: kern/51254 */ 1796 KASSERTMSG(!topdown || hint <= orig_hint, 1797 #else 1798 if (__predict_false(!(!topdown || hint <= orig_hint))) 1799 printf( 1800 #endif 1801 "map=%p hint=%#"PRIxVADDR" orig_hint=%#"PRIxVADDR 1802 " length=%#"PRIxVSIZE" uobj=%p uoffset=%#llx align=%"PRIxVSIZE 1803 " flags=%#x entry=%p (uvm_map_findspace line %d)", 1804 map, hint, orig_hint, 1805 length, uobj, (unsigned long long)uoffset, align, 1806 flags, entry, line); 1807 } 1808 1809 /* 1810 * uvm_map_findspace: find "length" sized space in "map". 1811 * 1812 * => "hint" is a hint about where we want it, unless UVM_FLAG_FIXED is 1813 * set in "flags" (in which case we insist on using "hint"). 1814 * => "result" is VA returned 1815 * => uobj/uoffset are to be used to handle VAC alignment, if required 1816 * => if "align" is non-zero, we attempt to align to that value. 1817 * => caller must at least have read-locked map 1818 * => returns NULL on failure, or pointer to prev. map entry if success 1819 * => note this is a cross between the old vm_map_findspace and vm_map_find 1820 */ 1821 1822 struct vm_map_entry * 1823 uvm_map_findspace(struct vm_map *map, vaddr_t hint, vsize_t length, 1824 vaddr_t *result /* OUT */, struct uvm_object *uobj, voff_t uoffset, 1825 vsize_t align, int flags) 1826 { 1827 #define INVARIANTS() \ 1828 uvm_findspace_invariants(map, orig_hint, length, uobj, uoffset, align,\ 1829 flags, hint, entry, __LINE__) 1830 struct vm_map_entry *entry = NULL; 1831 struct vm_map_entry *child, *prev, *tmp; 1832 vaddr_t orig_hint __diagused; 1833 const int topdown = map->flags & VM_MAP_TOPDOWN; 1834 int avail; 1835 UVMHIST_FUNC(__func__); 1836 UVMHIST_CALLARGS(maphist, "(map=%#jx, hint=%#jx, len=%ju, flags=%#jx...", 1837 (uintptr_t)map, hint, length, flags); 1838 UVMHIST_LOG(maphist, " uobj=%#jx, uoffset=%#jx, align=%#jx)", 1839 (uintptr_t)uobj, uoffset, align, 0); 1840 1841 KASSERT((flags & UVM_FLAG_COLORMATCH) != 0 || powerof2(align)); 1842 KASSERT((flags & UVM_FLAG_COLORMATCH) == 0 || align < uvmexp.ncolors); 1843 KASSERT((flags & UVM_FLAG_FIXED) == 0 || align == 0); 1844 1845 uvm_map_check(map, "map_findspace entry"); 1846 1847 /* 1848 * Clamp the hint to the VM map's min/max address, and remmeber 1849 * the clamped original hint. Remember the original hint, 1850 * clamped to the min/max address. If we are aligning, then we 1851 * may have to try again with no alignment constraint if we 1852 * fail the first time. 1853 * 1854 * We use the original hint to verify later that the search has 1855 * been monotonic -- that is, nonincreasing or nondecreasing, 1856 * according to topdown or !topdown respectively. But the 1857 * clamping is not monotonic. 1858 */ 1859 if (hint < vm_map_min(map)) { /* check ranges ... */ 1860 if (flags & UVM_FLAG_FIXED) { 1861 UVMHIST_LOG(maphist,"<- VA below map range",0,0,0,0); 1862 return (NULL); 1863 } 1864 hint = vm_map_min(map); 1865 } 1866 if (hint > vm_map_max(map)) { 1867 UVMHIST_LOG(maphist,"<- VA %#jx > range [%#jx->%#jx]", 1868 hint, vm_map_min(map), vm_map_max(map), 0); 1869 return (NULL); 1870 } 1871 orig_hint = hint; 1872 INVARIANTS(); 1873 1874 UVMHIST_LOG(maphist,"<- VA %#jx vs range [%#jx->%#jx]", 1875 hint, vm_map_min(map), vm_map_max(map), 0); 1876 1877 /* 1878 * hint may not be aligned properly; we need round up or down it 1879 * before proceeding further. 1880 */ 1881 if ((flags & UVM_FLAG_COLORMATCH) == 0) { 1882 uvm_map_align_va(&hint, align, topdown); 1883 INVARIANTS(); 1884 } 1885 1886 UVMHIST_LOG(maphist,"<- VA %#jx vs range [%#jx->%#jx]", 1887 hint, vm_map_min(map), vm_map_max(map), 0); 1888 /* 1889 * Look for the first possible address; if there's already 1890 * something at this address, we have to start after it. 1891 */ 1892 1893 /* 1894 * @@@: there are four, no, eight cases to consider. 1895 * 1896 * 0: found, fixed, bottom up -> fail 1897 * 1: found, fixed, top down -> fail 1898 * 2: found, not fixed, bottom up -> start after entry->end, 1899 * loop up 1900 * 3: found, not fixed, top down -> start before entry->start, 1901 * loop down 1902 * 4: not found, fixed, bottom up -> check entry->next->start, fail 1903 * 5: not found, fixed, top down -> check entry->next->start, fail 1904 * 6: not found, not fixed, bottom up -> check entry->next->start, 1905 * loop up 1906 * 7: not found, not fixed, top down -> check entry->next->start, 1907 * loop down 1908 * 1909 * as you can see, it reduces to roughly five cases, and that 1910 * adding top down mapping only adds one unique case (without 1911 * it, there would be four cases). 1912 */ 1913 1914 if ((flags & UVM_FLAG_FIXED) == 0 && 1915 hint == (topdown ? vm_map_max(map) : vm_map_min(map))) { 1916 /* 1917 * The uvm_map_findspace algorithm is monotonic -- for 1918 * topdown VM it starts with a high hint and returns a 1919 * lower free address; for !topdown VM it starts with a 1920 * low hint and returns a higher free address. As an 1921 * optimization, start with the first (highest for 1922 * topdown, lowest for !topdown) free address. 1923 * 1924 * XXX This `optimization' probably doesn't actually do 1925 * much in practice unless userland explicitly passes 1926 * the VM map's minimum or maximum address, which 1927 * varies from machine to machine (VM_MAX/MIN_ADDRESS, 1928 * e.g. 0x7fbfdfeff000 on amd64 but 0xfffffffff000 on 1929 * aarch64) and may vary according to other factors 1930 * like sysctl vm.user_va0_disable. In particular, if 1931 * the user specifies 0 as a hint to mmap, then mmap 1932 * will choose a default address which is usually _not_ 1933 * VM_MAX/MIN_ADDRESS but something else instead like 1934 * VM_MAX_ADDRESS - stack size - guard page overhead, 1935 * in which case this branch is never hit. 1936 * 1937 * In fact, this branch appears to have been broken for 1938 * two decades between when topdown was introduced in 1939 * ~2003 and when it was adapted to handle the topdown 1940 * case without violating the monotonicity assertion in 1941 * 2022. Maybe Someone^TM should either ditch the 1942 * optimization or find a better way to do it. 1943 */ 1944 entry = map->first_free; 1945 } else { 1946 if (uvm_map_lookup_entry(map, hint, &entry)) { 1947 /* "hint" address already in use ... */ 1948 if (flags & UVM_FLAG_FIXED) { 1949 UVMHIST_LOG(maphist, "<- fixed & VA in use", 1950 0, 0, 0, 0); 1951 return (NULL); 1952 } 1953 if (topdown) 1954 /* Start from lower gap. */ 1955 entry = entry->prev; 1956 } else if (flags & UVM_FLAG_FIXED) { 1957 if (entry->next->start >= hint + length && 1958 hint + length > hint) 1959 goto found; 1960 1961 /* "hint" address is gap but too small */ 1962 UVMHIST_LOG(maphist, "<- fixed mapping failed", 1963 0, 0, 0, 0); 1964 return (NULL); /* only one shot at it ... */ 1965 } else { 1966 /* 1967 * See if given hint fits in this gap. 1968 */ 1969 avail = uvm_map_space_avail(&hint, length, 1970 uoffset, align, flags, topdown, entry); 1971 INVARIANTS(); 1972 switch (avail) { 1973 case 1: 1974 goto found; 1975 case -1: 1976 goto wraparound; 1977 } 1978 1979 if (topdown) { 1980 /* 1981 * Still there is a chance to fit 1982 * if hint > entry->end. 1983 */ 1984 } else { 1985 /* Start from higher gap. */ 1986 entry = entry->next; 1987 if (entry == &map->header) 1988 goto notfound; 1989 goto nextgap; 1990 } 1991 } 1992 } 1993 1994 /* 1995 * Note that all UVM_FLAGS_FIXED case is already handled. 1996 */ 1997 KDASSERT((flags & UVM_FLAG_FIXED) == 0); 1998 1999 /* Try to find the space in the red-black tree */ 2000 2001 /* Check slot before any entry */ 2002 if (topdown) { 2003 KASSERTMSG(entry->next->start >= vm_map_min(map), 2004 "map=%p entry=%p entry->next=%p" 2005 " entry->next->start=0x%"PRIxVADDR" min=0x%"PRIxVADDR, 2006 map, entry, entry->next, 2007 entry->next->start, vm_map_min(map)); 2008 if (length > entry->next->start - vm_map_min(map)) 2009 hint = vm_map_min(map); /* XXX goto wraparound? */ 2010 else 2011 hint = entry->next->start - length; 2012 KASSERT(hint >= vm_map_min(map)); 2013 } else { 2014 hint = entry->end; 2015 } 2016 INVARIANTS(); 2017 avail = uvm_map_space_avail(&hint, length, uoffset, align, flags, 2018 topdown, entry); 2019 INVARIANTS(); 2020 switch (avail) { 2021 case 1: 2022 goto found; 2023 case -1: 2024 goto wraparound; 2025 } 2026 2027 nextgap: 2028 KDASSERT((flags & UVM_FLAG_FIXED) == 0); 2029 /* If there is not enough space in the whole tree, we fail */ 2030 tmp = ROOT_ENTRY(map); 2031 if (tmp == NULL || tmp->maxgap < length) 2032 goto notfound; 2033 2034 prev = NULL; /* previous candidate */ 2035 2036 /* Find an entry close to hint that has enough space */ 2037 for (; tmp;) { 2038 KASSERT(tmp->next->start == tmp->end + tmp->gap); 2039 if (topdown) { 2040 if (tmp->next->start < hint + length && 2041 (prev == NULL || tmp->end > prev->end)) { 2042 if (tmp->gap >= length) 2043 prev = tmp; 2044 else if ((child = LEFT_ENTRY(tmp)) != NULL 2045 && child->maxgap >= length) 2046 prev = tmp; 2047 } 2048 } else { 2049 if (tmp->end >= hint && 2050 (prev == NULL || tmp->end < prev->end)) { 2051 if (tmp->gap >= length) 2052 prev = tmp; 2053 else if ((child = RIGHT_ENTRY(tmp)) != NULL 2054 && child->maxgap >= length) 2055 prev = tmp; 2056 } 2057 } 2058 if (tmp->next->start < hint + length) 2059 child = RIGHT_ENTRY(tmp); 2060 else if (tmp->end > hint) 2061 child = LEFT_ENTRY(tmp); 2062 else { 2063 if (tmp->gap >= length) 2064 break; 2065 if (topdown) 2066 child = LEFT_ENTRY(tmp); 2067 else 2068 child = RIGHT_ENTRY(tmp); 2069 } 2070 if (child == NULL || child->maxgap < length) 2071 break; 2072 tmp = child; 2073 } 2074 2075 if (tmp != NULL && tmp->start < hint && hint < tmp->next->start) { 2076 /* 2077 * Check if the entry that we found satifies the 2078 * space requirement 2079 */ 2080 if (topdown) { 2081 if (hint > tmp->next->start - length) 2082 hint = tmp->next->start - length; 2083 } else { 2084 if (hint < tmp->end) 2085 hint = tmp->end; 2086 } 2087 INVARIANTS(); 2088 avail = uvm_map_space_avail(&hint, length, uoffset, align, 2089 flags, topdown, tmp); 2090 INVARIANTS(); 2091 switch (avail) { 2092 case 1: 2093 entry = tmp; 2094 goto found; 2095 case -1: 2096 goto wraparound; 2097 } 2098 if (tmp->gap >= length) 2099 goto listsearch; 2100 } 2101 if (prev == NULL) 2102 goto notfound; 2103 2104 if (topdown) { 2105 KASSERT(orig_hint >= prev->next->start - length || 2106 prev->next->start - length > prev->next->start); 2107 hint = prev->next->start - length; 2108 } else { 2109 KASSERT(orig_hint <= prev->end); 2110 hint = prev->end; 2111 } 2112 INVARIANTS(); 2113 avail = uvm_map_space_avail(&hint, length, uoffset, align, 2114 flags, topdown, prev); 2115 INVARIANTS(); 2116 switch (avail) { 2117 case 1: 2118 entry = prev; 2119 goto found; 2120 case -1: 2121 goto wraparound; 2122 } 2123 if (prev->gap >= length) 2124 goto listsearch; 2125 2126 if (topdown) 2127 tmp = LEFT_ENTRY(prev); 2128 else 2129 tmp = RIGHT_ENTRY(prev); 2130 for (;;) { 2131 KASSERT(tmp); 2132 KASSERTMSG(tmp->maxgap >= length, 2133 "tmp->maxgap=0x%"PRIxVSIZE" length=0x%"PRIxVSIZE, 2134 tmp->maxgap, length); 2135 if (topdown) 2136 child = RIGHT_ENTRY(tmp); 2137 else 2138 child = LEFT_ENTRY(tmp); 2139 if (child && child->maxgap >= length) { 2140 tmp = child; 2141 continue; 2142 } 2143 if (tmp->gap >= length) 2144 break; 2145 if (topdown) 2146 tmp = LEFT_ENTRY(tmp); 2147 else 2148 tmp = RIGHT_ENTRY(tmp); 2149 } 2150 2151 if (topdown) { 2152 KASSERT(orig_hint >= tmp->next->start - length || 2153 tmp->next->start - length > tmp->next->start); 2154 hint = tmp->next->start - length; 2155 } else { 2156 KASSERT(orig_hint <= tmp->end); 2157 hint = tmp->end; 2158 } 2159 INVARIANTS(); 2160 avail = uvm_map_space_avail(&hint, length, uoffset, align, 2161 flags, topdown, tmp); 2162 INVARIANTS(); 2163 switch (avail) { 2164 case 1: 2165 entry = tmp; 2166 goto found; 2167 case -1: 2168 goto wraparound; 2169 } 2170 2171 /* 2172 * The tree fails to find an entry because of offset or alignment 2173 * restrictions. Search the list instead. 2174 */ 2175 listsearch: 2176 /* 2177 * Look through the rest of the map, trying to fit a new region in 2178 * the gap between existing regions, or after the very last region. 2179 * note: entry->end = base VA of current gap, 2180 * entry->next->start = VA of end of current gap 2181 */ 2182 2183 INVARIANTS(); 2184 for (;;) { 2185 /* Update hint for current gap. */ 2186 hint = topdown ? entry->next->start - length : entry->end; 2187 INVARIANTS(); 2188 2189 /* See if it fits. */ 2190 avail = uvm_map_space_avail(&hint, length, uoffset, align, 2191 flags, topdown, entry); 2192 INVARIANTS(); 2193 switch (avail) { 2194 case 1: 2195 goto found; 2196 case -1: 2197 goto wraparound; 2198 } 2199 2200 /* Advance to next/previous gap */ 2201 if (topdown) { 2202 if (entry == &map->header) { 2203 UVMHIST_LOG(maphist, "<- failed (off start)", 2204 0,0,0,0); 2205 goto notfound; 2206 } 2207 entry = entry->prev; 2208 } else { 2209 entry = entry->next; 2210 if (entry == &map->header) { 2211 UVMHIST_LOG(maphist, "<- failed (off end)", 2212 0,0,0,0); 2213 goto notfound; 2214 } 2215 } 2216 } 2217 2218 found: 2219 SAVE_HINT(map, map->hint, entry); 2220 *result = hint; 2221 UVMHIST_LOG(maphist,"<- got it! (result=%#jx)", hint, 0,0,0); 2222 INVARIANTS(); 2223 KASSERT(entry->end <= hint); 2224 KASSERT(hint + length <= entry->next->start); 2225 return (entry); 2226 2227 wraparound: 2228 UVMHIST_LOG(maphist, "<- failed (wrap around)", 0,0,0,0); 2229 2230 return (NULL); 2231 2232 notfound: 2233 UVMHIST_LOG(maphist, "<- failed (notfound)", 0,0,0,0); 2234 2235 return (NULL); 2236 #undef INVARIANTS 2237 } 2238 2239 /* 2240 * U N M A P - m a i n h e l p e r f u n c t i o n s 2241 */ 2242 2243 /* 2244 * uvm_unmap_remove: remove mappings from a vm_map (from "start" up to "stop") 2245 * 2246 * => caller must check alignment and size 2247 * => map must be locked by caller 2248 * => we return a list of map entries that we've remove from the map 2249 * in "entry_list" 2250 */ 2251 2252 void 2253 uvm_unmap_remove(struct vm_map *map, vaddr_t start, vaddr_t end, 2254 struct vm_map_entry **entry_list /* OUT */, int flags) 2255 { 2256 struct vm_map_entry *entry, *first_entry, *next; 2257 vaddr_t len; 2258 UVMHIST_FUNC(__func__); 2259 UVMHIST_CALLARGS(maphist,"(map=%#jx, start=%#jx, end=%#jx)", 2260 (uintptr_t)map, start, end, 0); 2261 VM_MAP_RANGE_CHECK(map, start, end); 2262 2263 uvm_map_check(map, "unmap_remove entry"); 2264 2265 /* 2266 * find first entry 2267 */ 2268 2269 if (uvm_map_lookup_entry(map, start, &first_entry) == true) { 2270 /* clip and go... */ 2271 entry = first_entry; 2272 UVM_MAP_CLIP_START(map, entry, start); 2273 /* critical! prevents stale hint */ 2274 SAVE_HINT(map, entry, entry->prev); 2275 } else { 2276 entry = first_entry->next; 2277 } 2278 2279 /* 2280 * save the free space hint 2281 */ 2282 2283 if (map->first_free != &map->header && map->first_free->start >= start) 2284 map->first_free = entry->prev; 2285 2286 /* 2287 * note: we now re-use first_entry for a different task. we remove 2288 * a number of map entries from the map and save them in a linked 2289 * list headed by "first_entry". once we remove them from the map 2290 * the caller should unlock the map and drop the references to the 2291 * backing objects [c.f. uvm_unmap_detach]. the object is to 2292 * separate unmapping from reference dropping. why? 2293 * [1] the map has to be locked for unmapping 2294 * [2] the map need not be locked for reference dropping 2295 * [3] dropping references may trigger pager I/O, and if we hit 2296 * a pager that does synchronous I/O we may have to wait for it. 2297 * [4] we would like all waiting for I/O to occur with maps unlocked 2298 * so that we don't block other threads. 2299 */ 2300 2301 first_entry = NULL; 2302 *entry_list = NULL; 2303 2304 /* 2305 * break up the area into map entry sized regions and unmap. note 2306 * that all mappings have to be removed before we can even consider 2307 * dropping references to amaps or VM objects (otherwise we could end 2308 * up with a mapping to a page on the free list which would be very bad) 2309 */ 2310 2311 while ((entry != &map->header) && (entry->start < end)) { 2312 KASSERT((entry->flags & UVM_MAP_STATIC) == 0); 2313 2314 UVM_MAP_CLIP_END(map, entry, end); 2315 next = entry->next; 2316 len = entry->end - entry->start; 2317 2318 /* 2319 * unwire before removing addresses from the pmap; otherwise 2320 * unwiring will put the entries back into the pmap (XXX). 2321 */ 2322 2323 if (VM_MAPENT_ISWIRED(entry)) { 2324 uvm_map_entry_unwire(map, entry); 2325 } 2326 if (flags & UVM_FLAG_VAONLY) { 2327 2328 /* nothing */ 2329 2330 } else if ((map->flags & VM_MAP_PAGEABLE) == 0) { 2331 2332 /* 2333 * if the map is non-pageable, any pages mapped there 2334 * must be wired and entered with pmap_kenter_pa(), 2335 * and we should free any such pages immediately. 2336 * this is mostly used for kmem_map. 2337 */ 2338 KASSERT(vm_map_pmap(map) == pmap_kernel()); 2339 2340 uvm_km_pgremove_intrsafe(map, entry->start, entry->end); 2341 } else if (UVM_ET_ISOBJ(entry) && 2342 UVM_OBJ_IS_KERN_OBJECT(entry->object.uvm_obj)) { 2343 panic("%s: kernel object %p %p\n", 2344 __func__, map, entry); 2345 } else if (UVM_ET_ISOBJ(entry) || entry->aref.ar_amap) { 2346 /* 2347 * remove mappings the standard way. lock object 2348 * and/or amap to ensure vm_page state does not 2349 * change while in pmap_remove(). 2350 */ 2351 2352 #ifdef __HAVE_UNLOCKED_PMAP /* XXX temporary */ 2353 uvm_map_lock_entry(entry, RW_WRITER); 2354 #else 2355 uvm_map_lock_entry(entry, RW_READER); 2356 #endif 2357 pmap_remove(map->pmap, entry->start, entry->end); 2358 2359 /* 2360 * note: if map is dying, leave pmap_update() for 2361 * later. if the map is to be reused (exec) then 2362 * pmap_update() will be called. if the map is 2363 * being disposed of (exit) then pmap_destroy() 2364 * will be called. 2365 */ 2366 2367 if ((map->flags & VM_MAP_DYING) == 0) { 2368 pmap_update(vm_map_pmap(map)); 2369 } else { 2370 KASSERT(vm_map_pmap(map) != pmap_kernel()); 2371 } 2372 2373 uvm_map_unlock_entry(entry); 2374 } 2375 2376 #if defined(UVMDEBUG) 2377 /* 2378 * check if there's remaining mapping, 2379 * which is a bug in caller. 2380 */ 2381 2382 vaddr_t va; 2383 for (va = entry->start; va < entry->end; 2384 va += PAGE_SIZE) { 2385 if (pmap_extract(vm_map_pmap(map), va, NULL)) { 2386 panic("%s: %#"PRIxVADDR" has mapping", 2387 __func__, va); 2388 } 2389 } 2390 2391 if (VM_MAP_IS_KERNEL(map) && (flags & UVM_FLAG_NOWAIT) == 0) { 2392 uvm_km_check_empty(map, entry->start, entry->end); 2393 } 2394 #endif /* defined(UVMDEBUG) */ 2395 2396 /* 2397 * remove entry from map and put it on our list of entries 2398 * that we've nuked. then go to next entry. 2399 */ 2400 2401 UVMHIST_LOG(maphist, " removed map entry %#jx", 2402 (uintptr_t)entry, 0, 0, 0); 2403 2404 /* critical! prevents stale hint */ 2405 SAVE_HINT(map, entry, entry->prev); 2406 2407 uvm_map_entry_unlink(map, entry); 2408 KASSERT(map->size >= len); 2409 map->size -= len; 2410 entry->prev = NULL; 2411 entry->next = first_entry; 2412 first_entry = entry; 2413 entry = next; 2414 } 2415 2416 uvm_map_check(map, "unmap_remove leave"); 2417 2418 /* 2419 * now we've cleaned up the map and are ready for the caller to drop 2420 * references to the mapped objects. 2421 */ 2422 2423 *entry_list = first_entry; 2424 UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0); 2425 2426 if (map->flags & VM_MAP_WANTVA) { 2427 mutex_enter(&map->misc_lock); 2428 map->flags &= ~VM_MAP_WANTVA; 2429 cv_broadcast(&map->cv); 2430 mutex_exit(&map->misc_lock); 2431 } 2432 } 2433 2434 /* 2435 * uvm_unmap_detach: drop references in a chain of map entries 2436 * 2437 * => we will free the map entries as we traverse the list. 2438 */ 2439 2440 void 2441 uvm_unmap_detach(struct vm_map_entry *first_entry, int flags) 2442 { 2443 struct vm_map_entry *next_entry; 2444 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 2445 2446 while (first_entry) { 2447 KASSERT(!VM_MAPENT_ISWIRED(first_entry)); 2448 UVMHIST_LOG(maphist, 2449 " detach %#jx: amap=%#jx, obj=%#jx, submap?=%jd", 2450 (uintptr_t)first_entry, 2451 (uintptr_t)first_entry->aref.ar_amap, 2452 (uintptr_t)first_entry->object.uvm_obj, 2453 UVM_ET_ISSUBMAP(first_entry)); 2454 2455 /* 2456 * drop reference to amap, if we've got one 2457 */ 2458 2459 if (first_entry->aref.ar_amap) 2460 uvm_map_unreference_amap(first_entry, flags); 2461 2462 /* 2463 * drop reference to our backing object, if we've got one 2464 */ 2465 2466 KASSERT(!UVM_ET_ISSUBMAP(first_entry)); 2467 if (UVM_ET_ISOBJ(first_entry) && 2468 first_entry->object.uvm_obj->pgops->pgo_detach) { 2469 (*first_entry->object.uvm_obj->pgops->pgo_detach) 2470 (first_entry->object.uvm_obj); 2471 } 2472 next_entry = first_entry->next; 2473 uvm_mapent_free(first_entry); 2474 first_entry = next_entry; 2475 } 2476 UVMHIST_LOG(maphist, "<- done", 0,0,0,0); 2477 } 2478 2479 /* 2480 * E X T R A C T I O N F U N C T I O N S 2481 */ 2482 2483 /* 2484 * uvm_map_reserve: reserve space in a vm_map for future use. 2485 * 2486 * => we reserve space in a map by putting a dummy map entry in the 2487 * map (dummy means obj=NULL, amap=NULL, prot=VM_PROT_NONE) 2488 * => map should be unlocked (we will write lock it) 2489 * => we return true if we were able to reserve space 2490 * => XXXCDC: should be inline? 2491 */ 2492 2493 int 2494 uvm_map_reserve(struct vm_map *map, vsize_t size, 2495 vaddr_t offset /* hint for pmap_prefer */, 2496 vsize_t align /* alignment */, 2497 vaddr_t *raddr /* IN:hint, OUT: reserved VA */, 2498 uvm_flag_t flags /* UVM_FLAG_FIXED or UVM_FLAG_COLORMATCH or 0 */) 2499 { 2500 UVMHIST_FUNC(__func__); 2501 UVMHIST_CALLARGS(maphist, "(map=%#jx, size=%#jx, offset=%#jx, addr=%#jx)", 2502 (uintptr_t)map, size, offset, (uintptr_t)raddr); 2503 2504 size = round_page(size); 2505 2506 /* 2507 * reserve some virtual space. 2508 */ 2509 2510 if (uvm_map(map, raddr, size, NULL, offset, align, 2511 UVM_MAPFLAG(UVM_PROT_NONE, UVM_PROT_NONE, UVM_INH_NONE, 2512 UVM_ADV_RANDOM, UVM_FLAG_NOMERGE|flags)) != 0) { 2513 UVMHIST_LOG(maphist, "<- done (no VM)", 0,0,0,0); 2514 return (false); 2515 } 2516 2517 UVMHIST_LOG(maphist, "<- done (*raddr=%#jx)", *raddr,0,0,0); 2518 return (true); 2519 } 2520 2521 /* 2522 * uvm_map_replace: replace a reserved (blank) area of memory with 2523 * real mappings. 2524 * 2525 * => caller must WRITE-LOCK the map 2526 * => we return true if replacement was a success 2527 * => we expect the newents chain to have nnewents entrys on it and 2528 * we expect newents->prev to point to the last entry on the list 2529 * => note newents is allowed to be NULL 2530 */ 2531 2532 static int 2533 uvm_map_replace(struct vm_map *map, vaddr_t start, vaddr_t end, 2534 struct vm_map_entry *newents, int nnewents, vsize_t nsize, 2535 struct vm_map_entry **oldentryp) 2536 { 2537 struct vm_map_entry *oldent, *last; 2538 2539 uvm_map_check(map, "map_replace entry"); 2540 2541 /* 2542 * first find the blank map entry at the specified address 2543 */ 2544 2545 if (!uvm_map_lookup_entry(map, start, &oldent)) { 2546 return (false); 2547 } 2548 2549 /* 2550 * check to make sure we have a proper blank entry 2551 */ 2552 2553 if (end < oldent->end) { 2554 UVM_MAP_CLIP_END(map, oldent, end); 2555 } 2556 if (oldent->start != start || oldent->end != end || 2557 oldent->object.uvm_obj != NULL || oldent->aref.ar_amap != NULL) { 2558 return (false); 2559 } 2560 2561 #ifdef DIAGNOSTIC 2562 2563 /* 2564 * sanity check the newents chain 2565 */ 2566 2567 { 2568 struct vm_map_entry *tmpent = newents; 2569 int nent = 0; 2570 vsize_t sz = 0; 2571 vaddr_t cur = start; 2572 2573 while (tmpent) { 2574 nent++; 2575 sz += tmpent->end - tmpent->start; 2576 if (tmpent->start < cur) 2577 panic("uvm_map_replace1"); 2578 if (tmpent->start >= tmpent->end || tmpent->end > end) { 2579 panic("uvm_map_replace2: " 2580 "tmpent->start=%#"PRIxVADDR 2581 ", tmpent->end=%#"PRIxVADDR 2582 ", end=%#"PRIxVADDR, 2583 tmpent->start, tmpent->end, end); 2584 } 2585 cur = tmpent->end; 2586 if (tmpent->next) { 2587 if (tmpent->next->prev != tmpent) 2588 panic("uvm_map_replace3"); 2589 } else { 2590 if (newents->prev != tmpent) 2591 panic("uvm_map_replace4"); 2592 } 2593 tmpent = tmpent->next; 2594 } 2595 if (nent != nnewents) 2596 panic("uvm_map_replace5"); 2597 if (sz != nsize) 2598 panic("uvm_map_replace6"); 2599 } 2600 #endif 2601 2602 /* 2603 * map entry is a valid blank! replace it. (this does all the 2604 * work of map entry link/unlink...). 2605 */ 2606 2607 if (newents) { 2608 last = newents->prev; 2609 2610 /* critical: flush stale hints out of map */ 2611 SAVE_HINT(map, map->hint, newents); 2612 if (map->first_free == oldent) 2613 map->first_free = last; 2614 2615 last->next = oldent->next; 2616 last->next->prev = last; 2617 2618 /* Fix RB tree */ 2619 uvm_rb_remove(map, oldent); 2620 2621 newents->prev = oldent->prev; 2622 newents->prev->next = newents; 2623 map->nentries = map->nentries + (nnewents - 1); 2624 2625 /* Fixup the RB tree */ 2626 { 2627 int i; 2628 struct vm_map_entry *tmp; 2629 2630 tmp = newents; 2631 for (i = 0; i < nnewents && tmp; i++) { 2632 uvm_rb_insert(map, tmp); 2633 tmp = tmp->next; 2634 } 2635 } 2636 } else { 2637 /* NULL list of new entries: just remove the old one */ 2638 clear_hints(map, oldent); 2639 uvm_map_entry_unlink(map, oldent); 2640 } 2641 map->size -= end - start - nsize; 2642 2643 uvm_map_check(map, "map_replace leave"); 2644 2645 /* 2646 * now we can free the old blank entry and return. 2647 */ 2648 2649 *oldentryp = oldent; 2650 return (true); 2651 } 2652 2653 /* 2654 * uvm_map_extract: extract a mapping from a map and put it somewhere 2655 * (maybe removing the old mapping) 2656 * 2657 * => maps should be unlocked (we will write lock them) 2658 * => returns 0 on success, error code otherwise 2659 * => start must be page aligned 2660 * => len must be page sized 2661 * => flags: 2662 * UVM_EXTRACT_REMOVE: remove mappings from srcmap 2663 * UVM_EXTRACT_CONTIG: abort if unmapped area (advisory only) 2664 * UVM_EXTRACT_QREF: for a temporary extraction do quick obj refs 2665 * UVM_EXTRACT_FIXPROT: set prot to maxprot as we go 2666 * UVM_EXTRACT_PROT_ALL: set prot to UVM_PROT_ALL as we go 2667 * >>>NOTE: if you set REMOVE, you are not allowed to use CONTIG or QREF!<<< 2668 * >>>NOTE: QREF's must be unmapped via the QREF path, thus should only 2669 * be used from within the kernel in a kernel level map <<< 2670 */ 2671 2672 int 2673 uvm_map_extract(struct vm_map *srcmap, vaddr_t start, vsize_t len, 2674 struct vm_map *dstmap, vaddr_t *dstaddrp, int flags) 2675 { 2676 vaddr_t dstaddr, end, newend, oldoffset, fudge, orig_fudge; 2677 struct vm_map_entry *chain, *endchain, *entry, *orig_entry, *newentry, 2678 *deadentry, *oldentry; 2679 struct vm_map_entry *resentry = NULL; /* a dummy reservation entry */ 2680 vsize_t elen __unused; 2681 int nchain, error, copy_ok; 2682 vsize_t nsize; 2683 UVMHIST_FUNC(__func__); 2684 UVMHIST_CALLARGS(maphist,"(srcmap=%#jx,start=%#jx, len=%#jx", 2685 (uintptr_t)srcmap, start, len, 0); 2686 UVMHIST_LOG(maphist," ...,dstmap=%#jx, flags=%#jx)", 2687 (uintptr_t)dstmap, flags, 0, 0); 2688 2689 /* 2690 * step 0: sanity check: start must be on a page boundary, length 2691 * must be page sized. can't ask for CONTIG/QREF if you asked for 2692 * REMOVE. 2693 */ 2694 2695 KASSERTMSG((start & PAGE_MASK) == 0, "start=0x%"PRIxVADDR, start); 2696 KASSERTMSG((len & PAGE_MASK) == 0, "len=0x%"PRIxVADDR, len); 2697 KASSERT((flags & UVM_EXTRACT_REMOVE) == 0 || 2698 (flags & (UVM_EXTRACT_CONTIG|UVM_EXTRACT_QREF)) == 0); 2699 2700 /* 2701 * step 1: reserve space in the target map for the extracted area 2702 */ 2703 2704 if ((flags & UVM_EXTRACT_RESERVED) == 0) { 2705 dstaddr = vm_map_min(dstmap); 2706 if (!uvm_map_reserve(dstmap, len, start, 2707 atop(start) & uvmexp.colormask, &dstaddr, 2708 UVM_FLAG_COLORMATCH)) 2709 return (ENOMEM); 2710 KASSERT((atop(start ^ dstaddr) & uvmexp.colormask) == 0); 2711 *dstaddrp = dstaddr; /* pass address back to caller */ 2712 UVMHIST_LOG(maphist, " dstaddr=%#jx", dstaddr,0,0,0); 2713 } else { 2714 dstaddr = *dstaddrp; 2715 } 2716 2717 /* 2718 * step 2: setup for the extraction process loop by init'ing the 2719 * map entry chain, locking src map, and looking up the first useful 2720 * entry in the map. 2721 */ 2722 2723 end = start + len; 2724 newend = dstaddr + len; 2725 chain = endchain = NULL; 2726 nchain = 0; 2727 nsize = 0; 2728 vm_map_lock(srcmap); 2729 2730 if (uvm_map_lookup_entry(srcmap, start, &entry)) { 2731 2732 /* "start" is within an entry */ 2733 if (flags & UVM_EXTRACT_QREF) { 2734 2735 /* 2736 * for quick references we don't clip the entry, so 2737 * the entry may map space "before" the starting 2738 * virtual address... this is the "fudge" factor 2739 * (which can be non-zero only the first time 2740 * through the "while" loop in step 3). 2741 */ 2742 2743 fudge = start - entry->start; 2744 } else { 2745 2746 /* 2747 * normal reference: we clip the map to fit (thus 2748 * fudge is zero) 2749 */ 2750 2751 UVM_MAP_CLIP_START(srcmap, entry, start); 2752 SAVE_HINT(srcmap, srcmap->hint, entry->prev); 2753 fudge = 0; 2754 } 2755 } else { 2756 2757 /* "start" is not within an entry ... skip to next entry */ 2758 if (flags & UVM_EXTRACT_CONTIG) { 2759 error = EINVAL; 2760 goto bad; /* definite hole here ... */ 2761 } 2762 2763 entry = entry->next; 2764 fudge = 0; 2765 } 2766 2767 /* save values from srcmap for step 6 */ 2768 orig_entry = entry; 2769 orig_fudge = fudge; 2770 2771 /* 2772 * step 3: now start looping through the map entries, extracting 2773 * as we go. 2774 */ 2775 2776 while (entry->start < end && entry != &srcmap->header) { 2777 2778 /* if we are not doing a quick reference, clip it */ 2779 if ((flags & UVM_EXTRACT_QREF) == 0) 2780 UVM_MAP_CLIP_END(srcmap, entry, end); 2781 2782 /* clear needs_copy (allow chunking) */ 2783 if (UVM_ET_ISNEEDSCOPY(entry)) { 2784 amap_copy(srcmap, entry, 2785 AMAP_COPY_NOWAIT|AMAP_COPY_NOMERGE, start, end); 2786 if (UVM_ET_ISNEEDSCOPY(entry)) { /* failed? */ 2787 error = ENOMEM; 2788 goto bad; 2789 } 2790 2791 /* amap_copy could clip (during chunk)! update fudge */ 2792 if (fudge) { 2793 fudge = start - entry->start; 2794 orig_fudge = fudge; 2795 } 2796 } 2797 2798 /* calculate the offset of this from "start" */ 2799 oldoffset = (entry->start + fudge) - start; 2800 2801 /* allocate a new map entry */ 2802 newentry = uvm_mapent_alloc(dstmap, 0); 2803 if (newentry == NULL) { 2804 error = ENOMEM; 2805 goto bad; 2806 } 2807 2808 /* set up new map entry */ 2809 newentry->next = NULL; 2810 newentry->prev = endchain; 2811 newentry->start = dstaddr + oldoffset; 2812 newentry->end = 2813 newentry->start + (entry->end - (entry->start + fudge)); 2814 if (newentry->end > newend || newentry->end < newentry->start) 2815 newentry->end = newend; 2816 newentry->object.uvm_obj = entry->object.uvm_obj; 2817 if (newentry->object.uvm_obj) { 2818 if (newentry->object.uvm_obj->pgops->pgo_reference) 2819 newentry->object.uvm_obj->pgops-> 2820 pgo_reference(newentry->object.uvm_obj); 2821 newentry->offset = entry->offset + fudge; 2822 } else { 2823 newentry->offset = 0; 2824 } 2825 newentry->etype = entry->etype; 2826 if (flags & UVM_EXTRACT_PROT_ALL) { 2827 newentry->protection = newentry->max_protection = 2828 UVM_PROT_ALL; 2829 } else { 2830 newentry->protection = (flags & UVM_EXTRACT_FIXPROT) ? 2831 entry->max_protection : entry->protection; 2832 newentry->max_protection = entry->max_protection; 2833 } 2834 newentry->inheritance = entry->inheritance; 2835 newentry->wired_count = 0; 2836 newentry->aref.ar_amap = entry->aref.ar_amap; 2837 if (newentry->aref.ar_amap) { 2838 newentry->aref.ar_pageoff = 2839 entry->aref.ar_pageoff + (fudge >> PAGE_SHIFT); 2840 uvm_map_reference_amap(newentry, AMAP_SHARED | 2841 ((flags & UVM_EXTRACT_QREF) ? AMAP_REFALL : 0)); 2842 } else { 2843 newentry->aref.ar_pageoff = 0; 2844 } 2845 newentry->advice = entry->advice; 2846 if ((flags & UVM_EXTRACT_QREF) != 0) { 2847 newentry->flags |= UVM_MAP_NOMERGE; 2848 } 2849 2850 /* now link it on the chain */ 2851 nchain++; 2852 nsize += newentry->end - newentry->start; 2853 if (endchain == NULL) { 2854 chain = endchain = newentry; 2855 } else { 2856 endchain->next = newentry; 2857 endchain = newentry; 2858 } 2859 2860 /* end of 'while' loop! */ 2861 if ((flags & UVM_EXTRACT_CONTIG) && entry->end < end && 2862 (entry->next == &srcmap->header || 2863 entry->next->start != entry->end)) { 2864 error = EINVAL; 2865 goto bad; 2866 } 2867 entry = entry->next; 2868 fudge = 0; 2869 } 2870 2871 /* 2872 * step 4: close off chain (in format expected by uvm_map_replace) 2873 */ 2874 2875 if (chain) 2876 chain->prev = endchain; 2877 2878 /* 2879 * step 5: attempt to lock the dest map so we can pmap_copy. 2880 * note usage of copy_ok: 2881 * 1 => dstmap locked, pmap_copy ok, and we "replace" here (step 5) 2882 * 0 => dstmap unlocked, NO pmap_copy, and we will "replace" in step 7 2883 */ 2884 2885 if (srcmap == dstmap || vm_map_lock_try(dstmap) == true) { 2886 copy_ok = 1; 2887 if (!uvm_map_replace(dstmap, dstaddr, dstaddr+len, chain, 2888 nchain, nsize, &resentry)) { 2889 if (srcmap != dstmap) 2890 vm_map_unlock(dstmap); 2891 error = EIO; 2892 goto bad; 2893 } 2894 } else { 2895 copy_ok = 0; 2896 /* replace defered until step 7 */ 2897 } 2898 2899 /* 2900 * step 6: traverse the srcmap a second time to do the following: 2901 * - if we got a lock on the dstmap do pmap_copy 2902 * - if UVM_EXTRACT_REMOVE remove the entries 2903 * we make use of orig_entry and orig_fudge (saved in step 2) 2904 */ 2905 2906 if (copy_ok || (flags & UVM_EXTRACT_REMOVE)) { 2907 2908 /* purge possible stale hints from srcmap */ 2909 if (flags & UVM_EXTRACT_REMOVE) { 2910 SAVE_HINT(srcmap, srcmap->hint, orig_entry->prev); 2911 if (srcmap->first_free != &srcmap->header && 2912 srcmap->first_free->start >= start) 2913 srcmap->first_free = orig_entry->prev; 2914 } 2915 2916 entry = orig_entry; 2917 fudge = orig_fudge; 2918 deadentry = NULL; /* for UVM_EXTRACT_REMOVE */ 2919 2920 while (entry->start < end && entry != &srcmap->header) { 2921 if (copy_ok) { 2922 oldoffset = (entry->start + fudge) - start; 2923 elen = MIN(end, entry->end) - 2924 (entry->start + fudge); 2925 pmap_copy(dstmap->pmap, srcmap->pmap, 2926 dstaddr + oldoffset, elen, 2927 entry->start + fudge); 2928 } 2929 2930 /* we advance "entry" in the following if statement */ 2931 if (flags & UVM_EXTRACT_REMOVE) { 2932 #ifdef __HAVE_UNLOCKED_PMAP /* XXX temporary */ 2933 uvm_map_lock_entry(entry, RW_WRITER); 2934 #else 2935 uvm_map_lock_entry(entry, RW_READER); 2936 #endif 2937 pmap_remove(srcmap->pmap, entry->start, 2938 entry->end); 2939 uvm_map_unlock_entry(entry); 2940 oldentry = entry; /* save entry */ 2941 entry = entry->next; /* advance */ 2942 uvm_map_entry_unlink(srcmap, oldentry); 2943 /* add to dead list */ 2944 oldentry->next = deadentry; 2945 deadentry = oldentry; 2946 } else { 2947 entry = entry->next; /* advance */ 2948 } 2949 2950 /* end of 'while' loop */ 2951 fudge = 0; 2952 } 2953 pmap_update(srcmap->pmap); 2954 2955 /* 2956 * unlock dstmap. we will dispose of deadentry in 2957 * step 7 if needed 2958 */ 2959 2960 if (copy_ok && srcmap != dstmap) 2961 vm_map_unlock(dstmap); 2962 2963 } else { 2964 deadentry = NULL; 2965 } 2966 2967 /* 2968 * step 7: we are done with the source map, unlock. if copy_ok 2969 * is 0 then we have not replaced the dummy mapping in dstmap yet 2970 * and we need to do so now. 2971 */ 2972 2973 vm_map_unlock(srcmap); 2974 if ((flags & UVM_EXTRACT_REMOVE) && deadentry) 2975 uvm_unmap_detach(deadentry, 0); /* dispose of old entries */ 2976 2977 /* now do the replacement if we didn't do it in step 5 */ 2978 if (copy_ok == 0) { 2979 vm_map_lock(dstmap); 2980 error = uvm_map_replace(dstmap, dstaddr, dstaddr+len, chain, 2981 nchain, nsize, &resentry); 2982 vm_map_unlock(dstmap); 2983 2984 if (error == false) { 2985 error = EIO; 2986 goto bad2; 2987 } 2988 } 2989 2990 if (resentry != NULL) 2991 uvm_mapent_free(resentry); 2992 2993 return (0); 2994 2995 /* 2996 * bad: failure recovery 2997 */ 2998 bad: 2999 vm_map_unlock(srcmap); 3000 bad2: /* src already unlocked */ 3001 if (chain) 3002 uvm_unmap_detach(chain, 3003 (flags & UVM_EXTRACT_QREF) ? AMAP_REFALL : 0); 3004 3005 if (resentry != NULL) 3006 uvm_mapent_free(resentry); 3007 3008 if ((flags & UVM_EXTRACT_RESERVED) == 0) { 3009 uvm_unmap(dstmap, dstaddr, dstaddr+len); /* ??? */ 3010 } 3011 return (error); 3012 } 3013 3014 /* end of extraction functions */ 3015 3016 /* 3017 * uvm_map_submap: punch down part of a map into a submap 3018 * 3019 * => only the kernel_map is allowed to be submapped 3020 * => the purpose of submapping is to break up the locking granularity 3021 * of a larger map 3022 * => the range specified must have been mapped previously with a uvm_map() 3023 * call [with uobj==NULL] to create a blank map entry in the main map. 3024 * [And it had better still be blank!] 3025 * => maps which contain submaps should never be copied or forked. 3026 * => to remove a submap, use uvm_unmap() on the main map 3027 * and then uvm_map_deallocate() the submap. 3028 * => main map must be unlocked. 3029 * => submap must have been init'd and have a zero reference count. 3030 * [need not be locked as we don't actually reference it] 3031 */ 3032 3033 int 3034 uvm_map_submap(struct vm_map *map, vaddr_t start, vaddr_t end, 3035 struct vm_map *submap) 3036 { 3037 struct vm_map_entry *entry; 3038 int error; 3039 3040 vm_map_lock(map); 3041 VM_MAP_RANGE_CHECK(map, start, end); 3042 3043 if (uvm_map_lookup_entry(map, start, &entry)) { 3044 UVM_MAP_CLIP_START(map, entry, start); 3045 UVM_MAP_CLIP_END(map, entry, end); /* to be safe */ 3046 } else { 3047 entry = NULL; 3048 } 3049 3050 if (entry != NULL && 3051 entry->start == start && entry->end == end && 3052 entry->object.uvm_obj == NULL && entry->aref.ar_amap == NULL && 3053 !UVM_ET_ISCOPYONWRITE(entry) && !UVM_ET_ISNEEDSCOPY(entry)) { 3054 entry->etype |= UVM_ET_SUBMAP; 3055 entry->object.sub_map = submap; 3056 entry->offset = 0; 3057 uvm_map_reference(submap); 3058 error = 0; 3059 } else { 3060 error = EINVAL; 3061 } 3062 vm_map_unlock(map); 3063 3064 return error; 3065 } 3066 3067 /* 3068 * uvm_map_protect_user: change map protection on behalf of the user. 3069 * Enforces PAX settings as necessary. 3070 */ 3071 int 3072 uvm_map_protect_user(struct lwp *l, vaddr_t start, vaddr_t end, 3073 vm_prot_t new_prot) 3074 { 3075 int error; 3076 3077 if ((error = PAX_MPROTECT_VALIDATE(l, new_prot))) 3078 return error; 3079 3080 return uvm_map_protect(&l->l_proc->p_vmspace->vm_map, start, end, 3081 new_prot, false); 3082 } 3083 3084 3085 /* 3086 * uvm_map_protect: change map protection 3087 * 3088 * => set_max means set max_protection. 3089 * => map must be unlocked. 3090 */ 3091 3092 #define MASK(entry) (UVM_ET_ISCOPYONWRITE(entry) ? \ 3093 ~VM_PROT_WRITE : VM_PROT_ALL) 3094 3095 int 3096 uvm_map_protect(struct vm_map *map, vaddr_t start, vaddr_t end, 3097 vm_prot_t new_prot, bool set_max) 3098 { 3099 struct vm_map_entry *current, *entry; 3100 int error = 0; 3101 UVMHIST_FUNC(__func__); 3102 UVMHIST_CALLARGS(maphist,"(map=%#jx,start=%#jx,end=%#jx,new_prot=%#jx)", 3103 (uintptr_t)map, start, end, new_prot); 3104 3105 vm_map_lock(map); 3106 VM_MAP_RANGE_CHECK(map, start, end); 3107 if (uvm_map_lookup_entry(map, start, &entry)) { 3108 UVM_MAP_CLIP_START(map, entry, start); 3109 } else { 3110 entry = entry->next; 3111 } 3112 3113 /* 3114 * make a first pass to check for protection violations. 3115 */ 3116 3117 current = entry; 3118 while ((current != &map->header) && (current->start < end)) { 3119 if (UVM_ET_ISSUBMAP(current)) { 3120 error = EINVAL; 3121 goto out; 3122 } 3123 if ((new_prot & current->max_protection) != new_prot) { 3124 error = EACCES; 3125 goto out; 3126 } 3127 /* 3128 * Don't allow VM_PROT_EXECUTE to be set on entries that 3129 * point to vnodes that are associated with a NOEXEC file 3130 * system. 3131 */ 3132 if (UVM_ET_ISOBJ(current) && 3133 UVM_OBJ_IS_VNODE(current->object.uvm_obj)) { 3134 struct vnode *vp = 3135 (struct vnode *) current->object.uvm_obj; 3136 3137 if ((new_prot & VM_PROT_EXECUTE) != 0 && 3138 (vp->v_mount->mnt_flag & MNT_NOEXEC) != 0) { 3139 error = EACCES; 3140 goto out; 3141 } 3142 } 3143 3144 current = current->next; 3145 } 3146 3147 /* go back and fix up protections (no need to clip this time). */ 3148 3149 current = entry; 3150 while ((current != &map->header) && (current->start < end)) { 3151 vm_prot_t old_prot; 3152 3153 UVM_MAP_CLIP_END(map, current, end); 3154 old_prot = current->protection; 3155 if (set_max) 3156 current->protection = 3157 (current->max_protection = new_prot) & old_prot; 3158 else 3159 current->protection = new_prot; 3160 3161 /* 3162 * update physical map if necessary. worry about copy-on-write 3163 * here -- CHECK THIS XXX 3164 */ 3165 3166 if (current->protection != old_prot) { 3167 /* update pmap! */ 3168 #ifdef __HAVE_UNLOCKED_PMAP /* XXX temporary */ 3169 uvm_map_lock_entry(current, RW_WRITER); 3170 #else 3171 uvm_map_lock_entry(current, RW_READER); 3172 #endif 3173 pmap_protect(map->pmap, current->start, current->end, 3174 current->protection & MASK(current)); 3175 uvm_map_unlock_entry(current); 3176 3177 /* 3178 * If this entry points at a vnode, and the 3179 * protection includes VM_PROT_EXECUTE, mark 3180 * the vnode as VEXECMAP. 3181 */ 3182 if (UVM_ET_ISOBJ(current)) { 3183 struct uvm_object *uobj = 3184 current->object.uvm_obj; 3185 3186 if (UVM_OBJ_IS_VNODE(uobj) && 3187 (current->protection & VM_PROT_EXECUTE)) { 3188 vn_markexec((struct vnode *) uobj); 3189 } 3190 } 3191 } 3192 3193 /* 3194 * If the map is configured to lock any future mappings, 3195 * wire this entry now if the old protection was VM_PROT_NONE 3196 * and the new protection is not VM_PROT_NONE. 3197 */ 3198 3199 if ((map->flags & VM_MAP_WIREFUTURE) != 0 && 3200 VM_MAPENT_ISWIRED(current) == 0 && 3201 old_prot == VM_PROT_NONE && 3202 new_prot != VM_PROT_NONE) { 3203 3204 /* 3205 * We must call pmap_update() here because the 3206 * pmap_protect() call above might have removed some 3207 * pmap entries and uvm_map_pageable() might create 3208 * some new pmap entries that rely on the prior 3209 * removals being completely finished. 3210 */ 3211 3212 pmap_update(map->pmap); 3213 3214 if (uvm_map_pageable(map, current->start, 3215 current->end, false, 3216 UVM_LK_ENTER|UVM_LK_EXIT) != 0) { 3217 3218 /* 3219 * If locking the entry fails, remember the 3220 * error if it's the first one. Note we 3221 * still continue setting the protection in 3222 * the map, but will return the error 3223 * condition regardless. 3224 * 3225 * XXX Ignore what the actual error is, 3226 * XXX just call it a resource shortage 3227 * XXX so that it doesn't get confused 3228 * XXX what uvm_map_protect() itself would 3229 * XXX normally return. 3230 */ 3231 3232 error = ENOMEM; 3233 } 3234 } 3235 current = current->next; 3236 } 3237 pmap_update(map->pmap); 3238 3239 out: 3240 vm_map_unlock(map); 3241 3242 UVMHIST_LOG(maphist, "<- done, error=%jd",error,0,0,0); 3243 return error; 3244 } 3245 3246 #undef MASK 3247 3248 /* 3249 * uvm_map_inherit: set inheritance code for range of addrs in map. 3250 * 3251 * => map must be unlocked 3252 * => note that the inherit code is used during a "fork". see fork 3253 * code for details. 3254 */ 3255 3256 int 3257 uvm_map_inherit(struct vm_map *map, vaddr_t start, vaddr_t end, 3258 vm_inherit_t new_inheritance) 3259 { 3260 struct vm_map_entry *entry, *temp_entry; 3261 UVMHIST_FUNC(__func__); 3262 UVMHIST_CALLARGS(maphist,"(map=%#jx,start=%#jx,end=%#jx,new_inh=%#jx)", 3263 (uintptr_t)map, start, end, new_inheritance); 3264 3265 switch (new_inheritance) { 3266 case MAP_INHERIT_NONE: 3267 case MAP_INHERIT_COPY: 3268 case MAP_INHERIT_SHARE: 3269 case MAP_INHERIT_ZERO: 3270 break; 3271 default: 3272 UVMHIST_LOG(maphist,"<- done (INVALID ARG)",0,0,0,0); 3273 return EINVAL; 3274 } 3275 3276 vm_map_lock(map); 3277 VM_MAP_RANGE_CHECK(map, start, end); 3278 if (uvm_map_lookup_entry(map, start, &temp_entry)) { 3279 entry = temp_entry; 3280 UVM_MAP_CLIP_START(map, entry, start); 3281 } else { 3282 entry = temp_entry->next; 3283 } 3284 while ((entry != &map->header) && (entry->start < end)) { 3285 UVM_MAP_CLIP_END(map, entry, end); 3286 entry->inheritance = new_inheritance; 3287 entry = entry->next; 3288 } 3289 vm_map_unlock(map); 3290 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 3291 return 0; 3292 } 3293 3294 /* 3295 * uvm_map_advice: set advice code for range of addrs in map. 3296 * 3297 * => map must be unlocked 3298 */ 3299 3300 int 3301 uvm_map_advice(struct vm_map *map, vaddr_t start, vaddr_t end, int new_advice) 3302 { 3303 struct vm_map_entry *entry, *temp_entry; 3304 UVMHIST_FUNC(__func__); 3305 UVMHIST_CALLARGS(maphist,"(map=%#jx,start=%#jx,end=%#jx,new_adv=%#jx)", 3306 (uintptr_t)map, start, end, new_advice); 3307 3308 vm_map_lock(map); 3309 VM_MAP_RANGE_CHECK(map, start, end); 3310 if (uvm_map_lookup_entry(map, start, &temp_entry)) { 3311 entry = temp_entry; 3312 UVM_MAP_CLIP_START(map, entry, start); 3313 } else { 3314 entry = temp_entry->next; 3315 } 3316 3317 /* 3318 * XXXJRT: disallow holes? 3319 */ 3320 3321 while ((entry != &map->header) && (entry->start < end)) { 3322 UVM_MAP_CLIP_END(map, entry, end); 3323 3324 switch (new_advice) { 3325 case MADV_NORMAL: 3326 case MADV_RANDOM: 3327 case MADV_SEQUENTIAL: 3328 /* nothing special here */ 3329 break; 3330 3331 default: 3332 vm_map_unlock(map); 3333 UVMHIST_LOG(maphist,"<- done (INVALID ARG)",0,0,0,0); 3334 return EINVAL; 3335 } 3336 entry->advice = new_advice; 3337 entry = entry->next; 3338 } 3339 3340 vm_map_unlock(map); 3341 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 3342 return 0; 3343 } 3344 3345 /* 3346 * uvm_map_willneed: apply MADV_WILLNEED 3347 */ 3348 3349 int 3350 uvm_map_willneed(struct vm_map *map, vaddr_t start, vaddr_t end) 3351 { 3352 struct vm_map_entry *entry; 3353 UVMHIST_FUNC(__func__); 3354 UVMHIST_CALLARGS(maphist,"(map=%#jx,start=%#jx,end=%#jx)", 3355 (uintptr_t)map, start, end, 0); 3356 3357 vm_map_lock_read(map); 3358 VM_MAP_RANGE_CHECK(map, start, end); 3359 if (!uvm_map_lookup_entry(map, start, &entry)) { 3360 entry = entry->next; 3361 } 3362 while (entry->start < end) { 3363 struct vm_amap * const amap = entry->aref.ar_amap; 3364 struct uvm_object * const uobj = entry->object.uvm_obj; 3365 3366 KASSERT(entry != &map->header); 3367 KASSERT(start < entry->end); 3368 /* 3369 * For now, we handle only the easy but commonly-requested case. 3370 * ie. start prefetching of backing uobj pages. 3371 * 3372 * XXX It might be useful to pmap_enter() the already-in-core 3373 * pages by inventing a "weak" mode for uvm_fault() which would 3374 * only do the PGO_LOCKED pgo_get(). 3375 */ 3376 if (UVM_ET_ISOBJ(entry) && amap == NULL && uobj != NULL) { 3377 off_t offset; 3378 off_t size; 3379 3380 offset = entry->offset; 3381 if (start < entry->start) { 3382 offset += entry->start - start; 3383 } 3384 size = entry->offset + (entry->end - entry->start); 3385 if (entry->end < end) { 3386 size -= end - entry->end; 3387 } 3388 uvm_readahead(uobj, offset, size); 3389 } 3390 entry = entry->next; 3391 } 3392 vm_map_unlock_read(map); 3393 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 3394 return 0; 3395 } 3396 3397 /* 3398 * uvm_map_pageable: sets the pageability of a range in a map. 3399 * 3400 * => wires map entries. should not be used for transient page locking. 3401 * for that, use uvm_fault_wire()/uvm_fault_unwire() (see uvm_vslock()). 3402 * => regions specified as not pageable require lock-down (wired) memory 3403 * and page tables. 3404 * => map must never be read-locked 3405 * => if islocked is true, map is already write-locked 3406 * => we always unlock the map, since we must downgrade to a read-lock 3407 * to call uvm_fault_wire() 3408 * => XXXCDC: check this and try and clean it up. 3409 */ 3410 3411 int 3412 uvm_map_pageable(struct vm_map *map, vaddr_t start, vaddr_t end, 3413 bool new_pageable, int lockflags) 3414 { 3415 struct vm_map_entry *entry, *start_entry, *failed_entry; 3416 int rv; 3417 #ifdef DIAGNOSTIC 3418 u_int timestamp_save; 3419 #endif 3420 UVMHIST_FUNC(__func__); 3421 UVMHIST_CALLARGS(maphist,"(map=%#jx,start=%#jx,end=%#jx,new_pageable=%ju)", 3422 (uintptr_t)map, start, end, new_pageable); 3423 KASSERT(map->flags & VM_MAP_PAGEABLE); 3424 3425 if ((lockflags & UVM_LK_ENTER) == 0) 3426 vm_map_lock(map); 3427 VM_MAP_RANGE_CHECK(map, start, end); 3428 3429 /* 3430 * only one pageability change may take place at one time, since 3431 * uvm_fault_wire assumes it will be called only once for each 3432 * wiring/unwiring. therefore, we have to make sure we're actually 3433 * changing the pageability for the entire region. we do so before 3434 * making any changes. 3435 */ 3436 3437 if (uvm_map_lookup_entry(map, start, &start_entry) == false) { 3438 if ((lockflags & UVM_LK_EXIT) == 0) 3439 vm_map_unlock(map); 3440 3441 UVMHIST_LOG(maphist,"<- done (fault)",0,0,0,0); 3442 return EFAULT; 3443 } 3444 entry = start_entry; 3445 3446 if (start == end) { /* nothing required */ 3447 if ((lockflags & UVM_LK_EXIT) == 0) 3448 vm_map_unlock(map); 3449 3450 UVMHIST_LOG(maphist,"<- done (nothing)",0,0,0,0); 3451 return 0; 3452 } 3453 3454 /* 3455 * handle wiring and unwiring separately. 3456 */ 3457 3458 if (new_pageable) { /* unwire */ 3459 UVM_MAP_CLIP_START(map, entry, start); 3460 3461 /* 3462 * unwiring. first ensure that the range to be unwired is 3463 * really wired down and that there are no holes. 3464 */ 3465 3466 while ((entry != &map->header) && (entry->start < end)) { 3467 if (entry->wired_count == 0 || 3468 (entry->end < end && 3469 (entry->next == &map->header || 3470 entry->next->start > entry->end))) { 3471 if ((lockflags & UVM_LK_EXIT) == 0) 3472 vm_map_unlock(map); 3473 UVMHIST_LOG(maphist, "<- done (INVAL)",0,0,0,0); 3474 return EINVAL; 3475 } 3476 entry = entry->next; 3477 } 3478 3479 /* 3480 * POSIX 1003.1b - a single munlock call unlocks a region, 3481 * regardless of the number of mlock calls made on that 3482 * region. 3483 */ 3484 3485 entry = start_entry; 3486 while ((entry != &map->header) && (entry->start < end)) { 3487 UVM_MAP_CLIP_END(map, entry, end); 3488 if (VM_MAPENT_ISWIRED(entry)) 3489 uvm_map_entry_unwire(map, entry); 3490 entry = entry->next; 3491 } 3492 if ((lockflags & UVM_LK_EXIT) == 0) 3493 vm_map_unlock(map); 3494 UVMHIST_LOG(maphist,"<- done (OK UNWIRE)",0,0,0,0); 3495 return 0; 3496 } 3497 3498 /* 3499 * wire case: in two passes [XXXCDC: ugly block of code here] 3500 * 3501 * 1: holding the write lock, we create any anonymous maps that need 3502 * to be created. then we clip each map entry to the region to 3503 * be wired and increment its wiring count. 3504 * 3505 * 2: we downgrade to a read lock, and call uvm_fault_wire to fault 3506 * in the pages for any newly wired area (wired_count == 1). 3507 * 3508 * downgrading to a read lock for uvm_fault_wire avoids a possible 3509 * deadlock with another thread that may have faulted on one of 3510 * the pages to be wired (it would mark the page busy, blocking 3511 * us, then in turn block on the map lock that we hold). because 3512 * of problems in the recursive lock package, we cannot upgrade 3513 * to a write lock in vm_map_lookup. thus, any actions that 3514 * require the write lock must be done beforehand. because we 3515 * keep the read lock on the map, the copy-on-write status of the 3516 * entries we modify here cannot change. 3517 */ 3518 3519 while ((entry != &map->header) && (entry->start < end)) { 3520 if (VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 3521 3522 /* 3523 * perform actions of vm_map_lookup that need the 3524 * write lock on the map: create an anonymous map 3525 * for a copy-on-write region, or an anonymous map 3526 * for a zero-fill region. (XXXCDC: submap case 3527 * ok?) 3528 */ 3529 3530 if (!UVM_ET_ISSUBMAP(entry)) { /* not submap */ 3531 if (UVM_ET_ISNEEDSCOPY(entry) && 3532 ((entry->max_protection & VM_PROT_WRITE) || 3533 (entry->object.uvm_obj == NULL))) { 3534 amap_copy(map, entry, 0, start, end); 3535 /* XXXCDC: wait OK? */ 3536 } 3537 } 3538 } 3539 UVM_MAP_CLIP_START(map, entry, start); 3540 UVM_MAP_CLIP_END(map, entry, end); 3541 entry->wired_count++; 3542 3543 /* 3544 * Check for holes 3545 */ 3546 3547 if (entry->protection == VM_PROT_NONE || 3548 (entry->end < end && 3549 (entry->next == &map->header || 3550 entry->next->start > entry->end))) { 3551 3552 /* 3553 * found one. amap creation actions do not need to 3554 * be undone, but the wired counts need to be restored. 3555 */ 3556 3557 while (entry != &map->header && entry->end > start) { 3558 entry->wired_count--; 3559 entry = entry->prev; 3560 } 3561 if ((lockflags & UVM_LK_EXIT) == 0) 3562 vm_map_unlock(map); 3563 UVMHIST_LOG(maphist,"<- done (INVALID WIRE)",0,0,0,0); 3564 return EINVAL; 3565 } 3566 entry = entry->next; 3567 } 3568 3569 /* 3570 * Pass 2. 3571 */ 3572 3573 #ifdef DIAGNOSTIC 3574 timestamp_save = map->timestamp; 3575 #endif 3576 vm_map_busy(map); 3577 vm_map_unlock(map); 3578 3579 rv = 0; 3580 entry = start_entry; 3581 while (entry != &map->header && entry->start < end) { 3582 if (entry->wired_count == 1) { 3583 rv = uvm_fault_wire(map, entry->start, entry->end, 3584 entry->max_protection, 1); 3585 if (rv) { 3586 3587 /* 3588 * wiring failed. break out of the loop. 3589 * we'll clean up the map below, once we 3590 * have a write lock again. 3591 */ 3592 3593 break; 3594 } 3595 } 3596 entry = entry->next; 3597 } 3598 3599 if (rv) { /* failed? */ 3600 3601 /* 3602 * Get back to an exclusive (write) lock. 3603 */ 3604 3605 vm_map_lock(map); 3606 vm_map_unbusy(map); 3607 3608 #ifdef DIAGNOSTIC 3609 if (timestamp_save + 1 != map->timestamp) 3610 panic("uvm_map_pageable: stale map"); 3611 #endif 3612 3613 /* 3614 * first drop the wiring count on all the entries 3615 * which haven't actually been wired yet. 3616 */ 3617 3618 failed_entry = entry; 3619 while (entry != &map->header && entry->start < end) { 3620 entry->wired_count--; 3621 entry = entry->next; 3622 } 3623 3624 /* 3625 * now, unwire all the entries that were successfully 3626 * wired above. 3627 */ 3628 3629 entry = start_entry; 3630 while (entry != failed_entry) { 3631 entry->wired_count--; 3632 if (VM_MAPENT_ISWIRED(entry) == 0) 3633 uvm_map_entry_unwire(map, entry); 3634 entry = entry->next; 3635 } 3636 if ((lockflags & UVM_LK_EXIT) == 0) 3637 vm_map_unlock(map); 3638 UVMHIST_LOG(maphist, "<- done (RV=%jd)", rv,0,0,0); 3639 return (rv); 3640 } 3641 3642 if ((lockflags & UVM_LK_EXIT) == 0) { 3643 vm_map_unbusy(map); 3644 } else { 3645 3646 /* 3647 * Get back to an exclusive (write) lock. 3648 */ 3649 3650 vm_map_lock(map); 3651 vm_map_unbusy(map); 3652 } 3653 3654 UVMHIST_LOG(maphist,"<- done (OK WIRE)",0,0,0,0); 3655 return 0; 3656 } 3657 3658 /* 3659 * uvm_map_pageable_all: special case of uvm_map_pageable - affects 3660 * all mapped regions. 3661 * 3662 * => map must not be locked. 3663 * => if no flags are specified, all regions are unwired. 3664 * => XXXJRT: has some of the same problems as uvm_map_pageable() above. 3665 */ 3666 3667 int 3668 uvm_map_pageable_all(struct vm_map *map, int flags, vsize_t limit) 3669 { 3670 struct vm_map_entry *entry, *failed_entry; 3671 vsize_t size; 3672 int rv; 3673 #ifdef DIAGNOSTIC 3674 u_int timestamp_save; 3675 #endif 3676 UVMHIST_FUNC(__func__); 3677 UVMHIST_CALLARGS(maphist,"(map=%#jx,flags=%#jx)", (uintptr_t)map, flags, 3678 0, 0); 3679 3680 KASSERT(map->flags & VM_MAP_PAGEABLE); 3681 3682 vm_map_lock(map); 3683 3684 /* 3685 * handle wiring and unwiring separately. 3686 */ 3687 3688 if (flags == 0) { /* unwire */ 3689 3690 /* 3691 * POSIX 1003.1b -- munlockall unlocks all regions, 3692 * regardless of how many times mlockall has been called. 3693 */ 3694 3695 for (entry = map->header.next; entry != &map->header; 3696 entry = entry->next) { 3697 if (VM_MAPENT_ISWIRED(entry)) 3698 uvm_map_entry_unwire(map, entry); 3699 } 3700 map->flags &= ~VM_MAP_WIREFUTURE; 3701 vm_map_unlock(map); 3702 UVMHIST_LOG(maphist,"<- done (OK UNWIRE)",0,0,0,0); 3703 return 0; 3704 } 3705 3706 if (flags & MCL_FUTURE) { 3707 3708 /* 3709 * must wire all future mappings; remember this. 3710 */ 3711 3712 map->flags |= VM_MAP_WIREFUTURE; 3713 } 3714 3715 if ((flags & MCL_CURRENT) == 0) { 3716 3717 /* 3718 * no more work to do! 3719 */ 3720 3721 UVMHIST_LOG(maphist,"<- done (OK no wire)",0,0,0,0); 3722 vm_map_unlock(map); 3723 return 0; 3724 } 3725 3726 /* 3727 * wire case: in three passes [XXXCDC: ugly block of code here] 3728 * 3729 * 1: holding the write lock, count all pages mapped by non-wired 3730 * entries. if this would cause us to go over our limit, we fail. 3731 * 3732 * 2: still holding the write lock, we create any anonymous maps that 3733 * need to be created. then we increment its wiring count. 3734 * 3735 * 3: we downgrade to a read lock, and call uvm_fault_wire to fault 3736 * in the pages for any newly wired area (wired_count == 1). 3737 * 3738 * downgrading to a read lock for uvm_fault_wire avoids a possible 3739 * deadlock with another thread that may have faulted on one of 3740 * the pages to be wired (it would mark the page busy, blocking 3741 * us, then in turn block on the map lock that we hold). because 3742 * of problems in the recursive lock package, we cannot upgrade 3743 * to a write lock in vm_map_lookup. thus, any actions that 3744 * require the write lock must be done beforehand. because we 3745 * keep the read lock on the map, the copy-on-write status of the 3746 * entries we modify here cannot change. 3747 */ 3748 3749 for (size = 0, entry = map->header.next; entry != &map->header; 3750 entry = entry->next) { 3751 if (entry->protection != VM_PROT_NONE && 3752 VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 3753 size += entry->end - entry->start; 3754 } 3755 } 3756 3757 if (atop(size) + uvmexp.wired > uvmexp.wiredmax) { 3758 vm_map_unlock(map); 3759 return ENOMEM; 3760 } 3761 3762 if (limit != 0 && 3763 (size + ptoa(pmap_wired_count(vm_map_pmap(map))) > limit)) { 3764 vm_map_unlock(map); 3765 return ENOMEM; 3766 } 3767 3768 /* 3769 * Pass 2. 3770 */ 3771 3772 for (entry = map->header.next; entry != &map->header; 3773 entry = entry->next) { 3774 if (entry->protection == VM_PROT_NONE) 3775 continue; 3776 if (VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 3777 3778 /* 3779 * perform actions of vm_map_lookup that need the 3780 * write lock on the map: create an anonymous map 3781 * for a copy-on-write region, or an anonymous map 3782 * for a zero-fill region. (XXXCDC: submap case 3783 * ok?) 3784 */ 3785 3786 if (!UVM_ET_ISSUBMAP(entry)) { /* not submap */ 3787 if (UVM_ET_ISNEEDSCOPY(entry) && 3788 ((entry->max_protection & VM_PROT_WRITE) || 3789 (entry->object.uvm_obj == NULL))) { 3790 amap_copy(map, entry, 0, entry->start, 3791 entry->end); 3792 /* XXXCDC: wait OK? */ 3793 } 3794 } 3795 } 3796 entry->wired_count++; 3797 } 3798 3799 /* 3800 * Pass 3. 3801 */ 3802 3803 #ifdef DIAGNOSTIC 3804 timestamp_save = map->timestamp; 3805 #endif 3806 vm_map_busy(map); 3807 vm_map_unlock(map); 3808 3809 rv = 0; 3810 for (entry = map->header.next; entry != &map->header; 3811 entry = entry->next) { 3812 if (entry->wired_count == 1) { 3813 rv = uvm_fault_wire(map, entry->start, entry->end, 3814 entry->max_protection, 1); 3815 if (rv) { 3816 3817 /* 3818 * wiring failed. break out of the loop. 3819 * we'll clean up the map below, once we 3820 * have a write lock again. 3821 */ 3822 3823 break; 3824 } 3825 } 3826 } 3827 3828 if (rv) { 3829 3830 /* 3831 * Get back an exclusive (write) lock. 3832 */ 3833 3834 vm_map_lock(map); 3835 vm_map_unbusy(map); 3836 3837 #ifdef DIAGNOSTIC 3838 if (timestamp_save + 1 != map->timestamp) 3839 panic("uvm_map_pageable_all: stale map"); 3840 #endif 3841 3842 /* 3843 * first drop the wiring count on all the entries 3844 * which haven't actually been wired yet. 3845 * 3846 * Skip VM_PROT_NONE entries like we did above. 3847 */ 3848 3849 failed_entry = entry; 3850 for (/* nothing */; entry != &map->header; 3851 entry = entry->next) { 3852 if (entry->protection == VM_PROT_NONE) 3853 continue; 3854 entry->wired_count--; 3855 } 3856 3857 /* 3858 * now, unwire all the entries that were successfully 3859 * wired above. 3860 * 3861 * Skip VM_PROT_NONE entries like we did above. 3862 */ 3863 3864 for (entry = map->header.next; entry != failed_entry; 3865 entry = entry->next) { 3866 if (entry->protection == VM_PROT_NONE) 3867 continue; 3868 entry->wired_count--; 3869 if (VM_MAPENT_ISWIRED(entry)) 3870 uvm_map_entry_unwire(map, entry); 3871 } 3872 vm_map_unlock(map); 3873 UVMHIST_LOG(maphist,"<- done (RV=%jd)", rv,0,0,0); 3874 return (rv); 3875 } 3876 3877 vm_map_unbusy(map); 3878 3879 UVMHIST_LOG(maphist,"<- done (OK WIRE)",0,0,0,0); 3880 return 0; 3881 } 3882 3883 /* 3884 * uvm_map_clean: clean out a map range 3885 * 3886 * => valid flags: 3887 * if (flags & PGO_CLEANIT): dirty pages are cleaned first 3888 * if (flags & PGO_SYNCIO): dirty pages are written synchronously 3889 * if (flags & PGO_DEACTIVATE): any cached pages are deactivated after clean 3890 * if (flags & PGO_FREE): any cached pages are freed after clean 3891 * => returns an error if any part of the specified range isn't mapped 3892 * => never a need to flush amap layer since the anonymous memory has 3893 * no permanent home, but may deactivate pages there 3894 * => called from sys_msync() and sys_madvise() 3895 * => caller must not have map locked 3896 */ 3897 3898 int 3899 uvm_map_clean(struct vm_map *map, vaddr_t start, vaddr_t end, int flags) 3900 { 3901 struct vm_map_entry *current, *entry; 3902 struct uvm_object *uobj; 3903 struct vm_amap *amap; 3904 struct vm_anon *anon; 3905 struct vm_page *pg; 3906 vaddr_t offset; 3907 vsize_t size; 3908 voff_t uoff; 3909 int error, refs; 3910 UVMHIST_FUNC(__func__); 3911 UVMHIST_CALLARGS(maphist,"(map=%#jx,start=%#jx,end=%#jx,flags=%#jx)", 3912 (uintptr_t)map, start, end, flags); 3913 3914 KASSERT((flags & (PGO_FREE|PGO_DEACTIVATE)) != 3915 (PGO_FREE|PGO_DEACTIVATE)); 3916 3917 vm_map_lock(map); 3918 VM_MAP_RANGE_CHECK(map, start, end); 3919 if (!uvm_map_lookup_entry(map, start, &entry)) { 3920 vm_map_unlock(map); 3921 return EFAULT; 3922 } 3923 3924 /* 3925 * Make a first pass to check for holes and wiring problems. 3926 */ 3927 3928 for (current = entry; current->start < end; current = current->next) { 3929 if (UVM_ET_ISSUBMAP(current)) { 3930 vm_map_unlock(map); 3931 return EINVAL; 3932 } 3933 if ((flags & PGO_FREE) != 0 && VM_MAPENT_ISWIRED(entry)) { 3934 vm_map_unlock(map); 3935 return EBUSY; 3936 } 3937 if (end <= current->end) { 3938 break; 3939 } 3940 if (current->end != current->next->start) { 3941 vm_map_unlock(map); 3942 return EFAULT; 3943 } 3944 } 3945 3946 vm_map_busy(map); 3947 vm_map_unlock(map); 3948 error = 0; 3949 for (current = entry; start < end; current = current->next) { 3950 amap = current->aref.ar_amap; /* upper layer */ 3951 uobj = current->object.uvm_obj; /* lower layer */ 3952 KASSERT(start >= current->start); 3953 3954 /* 3955 * No amap cleaning necessary if: 3956 * 3957 * (1) There's no amap. 3958 * 3959 * (2) We're not deactivating or freeing pages. 3960 */ 3961 3962 if (amap == NULL || (flags & (PGO_DEACTIVATE|PGO_FREE)) == 0) 3963 goto flush_object; 3964 3965 offset = start - current->start; 3966 size = MIN(end, current->end) - start; 3967 3968 amap_lock(amap, RW_WRITER); 3969 for ( ; size != 0; size -= PAGE_SIZE, offset += PAGE_SIZE) { 3970 anon = amap_lookup(¤t->aref, offset); 3971 if (anon == NULL) 3972 continue; 3973 3974 KASSERT(anon->an_lock == amap->am_lock); 3975 pg = anon->an_page; 3976 if (pg == NULL) { 3977 continue; 3978 } 3979 if (pg->flags & PG_BUSY) { 3980 continue; 3981 } 3982 3983 switch (flags & (PGO_CLEANIT|PGO_FREE|PGO_DEACTIVATE)) { 3984 3985 /* 3986 * In these first 3 cases, we just deactivate the page. 3987 */ 3988 3989 case PGO_CLEANIT|PGO_FREE: 3990 case PGO_CLEANIT|PGO_DEACTIVATE: 3991 case PGO_DEACTIVATE: 3992 deactivate_it: 3993 /* 3994 * skip the page if it's loaned or wired, 3995 * since it shouldn't be on a paging queue 3996 * at all in these cases. 3997 */ 3998 3999 if (pg->loan_count != 0 || 4000 pg->wire_count != 0) { 4001 continue; 4002 } 4003 KASSERT(pg->uanon == anon); 4004 uvm_pagelock(pg); 4005 uvm_pagedeactivate(pg); 4006 uvm_pageunlock(pg); 4007 continue; 4008 4009 case PGO_FREE: 4010 4011 /* 4012 * If there are multiple references to 4013 * the amap, just deactivate the page. 4014 */ 4015 4016 if (amap_refs(amap) > 1) 4017 goto deactivate_it; 4018 4019 /* skip the page if it's wired */ 4020 if (pg->wire_count != 0) { 4021 continue; 4022 } 4023 amap_unadd(¤t->aref, offset); 4024 refs = --anon->an_ref; 4025 if (refs == 0) { 4026 uvm_anfree(anon); 4027 } 4028 continue; 4029 } 4030 } 4031 amap_unlock(amap); 4032 4033 flush_object: 4034 /* 4035 * flush pages if we've got a valid backing object. 4036 * note that we must always clean object pages before 4037 * freeing them since otherwise we could reveal stale 4038 * data from files. 4039 */ 4040 4041 uoff = current->offset + (start - current->start); 4042 size = MIN(end, current->end) - start; 4043 if (uobj != NULL) { 4044 rw_enter(uobj->vmobjlock, RW_WRITER); 4045 if (uobj->pgops->pgo_put != NULL) 4046 error = (uobj->pgops->pgo_put)(uobj, uoff, 4047 uoff + size, flags | PGO_CLEANIT); 4048 else 4049 error = 0; 4050 } 4051 start += size; 4052 } 4053 vm_map_unbusy(map); 4054 return error; 4055 } 4056 4057 4058 /* 4059 * uvm_map_checkprot: check protection in map 4060 * 4061 * => must allow specified protection in a fully allocated region. 4062 * => map must be read or write locked by caller. 4063 */ 4064 4065 bool 4066 uvm_map_checkprot(struct vm_map *map, vaddr_t start, vaddr_t end, 4067 vm_prot_t protection) 4068 { 4069 struct vm_map_entry *entry; 4070 struct vm_map_entry *tmp_entry; 4071 4072 if (!uvm_map_lookup_entry(map, start, &tmp_entry)) { 4073 return (false); 4074 } 4075 entry = tmp_entry; 4076 while (start < end) { 4077 if (entry == &map->header) { 4078 return (false); 4079 } 4080 4081 /* 4082 * no holes allowed 4083 */ 4084 4085 if (start < entry->start) { 4086 return (false); 4087 } 4088 4089 /* 4090 * check protection associated with entry 4091 */ 4092 4093 if ((entry->protection & protection) != protection) { 4094 return (false); 4095 } 4096 start = entry->end; 4097 entry = entry->next; 4098 } 4099 return (true); 4100 } 4101 4102 /* 4103 * uvmspace_alloc: allocate a vmspace structure. 4104 * 4105 * - structure includes vm_map and pmap 4106 * - XXX: no locking on this structure 4107 * - refcnt set to 1, rest must be init'd by caller 4108 */ 4109 struct vmspace * 4110 uvmspace_alloc(vaddr_t vmin, vaddr_t vmax, bool topdown) 4111 { 4112 struct vmspace *vm; 4113 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 4114 4115 vm = pool_cache_get(&uvm_vmspace_cache, PR_WAITOK); 4116 uvmspace_init(vm, NULL, vmin, vmax, topdown); 4117 UVMHIST_LOG(maphist,"<- done (vm=%#jx)", (uintptr_t)vm, 0, 0, 0); 4118 return (vm); 4119 } 4120 4121 /* 4122 * uvmspace_init: initialize a vmspace structure. 4123 * 4124 * - XXX: no locking on this structure 4125 * - refcnt set to 1, rest must be init'd by caller 4126 */ 4127 void 4128 uvmspace_init(struct vmspace *vm, struct pmap *pmap, vaddr_t vmin, 4129 vaddr_t vmax, bool topdown) 4130 { 4131 UVMHIST_FUNC(__func__); 4132 UVMHIST_CALLARGS(maphist, "(vm=%#jx, pmap=%#jx, vmin=%#jx, vmax=%#jx", 4133 (uintptr_t)vm, (uintptr_t)pmap, vmin, vmax); 4134 UVMHIST_LOG(maphist, " topdown=%ju)", topdown, 0, 0, 0); 4135 4136 memset(vm, 0, sizeof(*vm)); 4137 uvm_map_setup(&vm->vm_map, vmin, vmax, VM_MAP_PAGEABLE 4138 | (topdown ? VM_MAP_TOPDOWN : 0) 4139 ); 4140 if (pmap) 4141 pmap_reference(pmap); 4142 else 4143 pmap = pmap_create(); 4144 vm->vm_map.pmap = pmap; 4145 vm->vm_refcnt = 1; 4146 UVMHIST_LOG(maphist,"<- done",0,0,0,0); 4147 } 4148 4149 /* 4150 * uvmspace_share: share a vmspace between two processes 4151 * 4152 * - used for vfork, threads(?) 4153 */ 4154 4155 void 4156 uvmspace_share(struct proc *p1, struct proc *p2) 4157 { 4158 4159 uvmspace_addref(p1->p_vmspace); 4160 p2->p_vmspace = p1->p_vmspace; 4161 } 4162 4163 #if 0 4164 4165 /* 4166 * uvmspace_unshare: ensure that process "p" has its own, unshared, vmspace 4167 * 4168 * - XXX: no locking on vmspace 4169 */ 4170 4171 void 4172 uvmspace_unshare(struct lwp *l) 4173 { 4174 struct proc *p = l->l_proc; 4175 struct vmspace *nvm, *ovm = p->p_vmspace; 4176 4177 if (ovm->vm_refcnt == 1) 4178 /* nothing to do: vmspace isn't shared in the first place */ 4179 return; 4180 4181 /* make a new vmspace, still holding old one */ 4182 nvm = uvmspace_fork(ovm); 4183 4184 kpreempt_disable(); 4185 pmap_deactivate(l); /* unbind old vmspace */ 4186 p->p_vmspace = nvm; 4187 pmap_activate(l); /* switch to new vmspace */ 4188 kpreempt_enable(); 4189 4190 uvmspace_free(ovm); /* drop reference to old vmspace */ 4191 } 4192 4193 #endif 4194 4195 4196 /* 4197 * uvmspace_spawn: a new process has been spawned and needs a vmspace 4198 */ 4199 4200 void 4201 uvmspace_spawn(struct lwp *l, vaddr_t start, vaddr_t end, bool topdown) 4202 { 4203 struct proc *p = l->l_proc; 4204 struct vmspace *nvm; 4205 4206 #ifdef __HAVE_CPU_VMSPACE_EXEC 4207 cpu_vmspace_exec(l, start, end); 4208 #endif 4209 4210 nvm = uvmspace_alloc(start, end, topdown); 4211 kpreempt_disable(); 4212 p->p_vmspace = nvm; 4213 pmap_activate(l); 4214 kpreempt_enable(); 4215 } 4216 4217 /* 4218 * uvmspace_exec: the process wants to exec a new program 4219 */ 4220 4221 void 4222 uvmspace_exec(struct lwp *l, vaddr_t start, vaddr_t end, bool topdown) 4223 { 4224 struct proc *p = l->l_proc; 4225 struct vmspace *nvm, *ovm = p->p_vmspace; 4226 struct vm_map *map; 4227 int flags; 4228 4229 KASSERT(ovm != NULL); 4230 #ifdef __HAVE_CPU_VMSPACE_EXEC 4231 cpu_vmspace_exec(l, start, end); 4232 #endif 4233 4234 map = &ovm->vm_map; 4235 /* 4236 * see if more than one process is using this vmspace... 4237 */ 4238 4239 if (ovm->vm_refcnt == 1 4240 && topdown == ((ovm->vm_map.flags & VM_MAP_TOPDOWN) != 0)) { 4241 4242 /* 4243 * if p is the only process using its vmspace then we can safely 4244 * recycle that vmspace for the program that is being exec'd. 4245 * But only if TOPDOWN matches the requested value for the new 4246 * vm space! 4247 */ 4248 4249 /* 4250 * SYSV SHM semantics require us to kill all segments on an exec 4251 */ 4252 if (uvm_shmexit && ovm->vm_shm) 4253 (*uvm_shmexit)(ovm); 4254 4255 /* 4256 * POSIX 1003.1b -- "lock future mappings" is revoked 4257 * when a process execs another program image. 4258 */ 4259 4260 map->flags &= ~VM_MAP_WIREFUTURE; 4261 4262 /* 4263 * now unmap the old program. 4264 * 4265 * XXX set VM_MAP_DYING for the duration, so pmap_update() 4266 * is not called until the pmap has been totally cleared out 4267 * after pmap_remove_all(), or it can confuse some pmap 4268 * implementations. it would be nice to handle this by 4269 * deferring the pmap_update() while it is known the address 4270 * space is not visible to any user LWP other than curlwp, 4271 * but there isn't an elegant way of inferring that right 4272 * now. 4273 */ 4274 4275 flags = pmap_remove_all(map->pmap) ? UVM_FLAG_VAONLY : 0; 4276 map->flags |= VM_MAP_DYING; 4277 uvm_unmap1(map, vm_map_min(map), vm_map_max(map), flags); 4278 map->flags &= ~VM_MAP_DYING; 4279 pmap_update(map->pmap); 4280 KASSERT(map->header.prev == &map->header); 4281 KASSERT(map->nentries == 0); 4282 4283 /* 4284 * resize the map 4285 */ 4286 4287 vm_map_setmin(map, start); 4288 vm_map_setmax(map, end); 4289 } else { 4290 4291 /* 4292 * p's vmspace is being shared, so we can't reuse it for p since 4293 * it is still being used for others. allocate a new vmspace 4294 * for p 4295 */ 4296 4297 nvm = uvmspace_alloc(start, end, topdown); 4298 4299 /* 4300 * install new vmspace and drop our ref to the old one. 4301 */ 4302 4303 kpreempt_disable(); 4304 pmap_deactivate(l); 4305 p->p_vmspace = nvm; 4306 pmap_activate(l); 4307 kpreempt_enable(); 4308 4309 uvmspace_free(ovm); 4310 } 4311 } 4312 4313 /* 4314 * uvmspace_addref: add a reference to a vmspace. 4315 */ 4316 4317 void 4318 uvmspace_addref(struct vmspace *vm) 4319 { 4320 4321 KASSERT((vm->vm_map.flags & VM_MAP_DYING) == 0); 4322 KASSERT(vm->vm_refcnt > 0); 4323 atomic_inc_uint(&vm->vm_refcnt); 4324 } 4325 4326 /* 4327 * uvmspace_free: free a vmspace data structure 4328 */ 4329 4330 void 4331 uvmspace_free(struct vmspace *vm) 4332 { 4333 struct vm_map_entry *dead_entries; 4334 struct vm_map *map = &vm->vm_map; 4335 int flags; 4336 4337 UVMHIST_FUNC(__func__); 4338 UVMHIST_CALLARGS(maphist,"(vm=%#jx) ref=%jd", (uintptr_t)vm, 4339 vm->vm_refcnt, 0, 0); 4340 4341 membar_release(); 4342 if (atomic_dec_uint_nv(&vm->vm_refcnt) > 0) 4343 return; 4344 membar_acquire(); 4345 4346 /* 4347 * at this point, there should be no other references to the map. 4348 * delete all of the mappings, then destroy the pmap. 4349 */ 4350 4351 map->flags |= VM_MAP_DYING; 4352 flags = pmap_remove_all(map->pmap) ? UVM_FLAG_VAONLY : 0; 4353 4354 /* Get rid of any SYSV shared memory segments. */ 4355 if (uvm_shmexit && vm->vm_shm != NULL) 4356 (*uvm_shmexit)(vm); 4357 4358 if (map->nentries) { 4359 uvm_unmap_remove(map, vm_map_min(map), vm_map_max(map), 4360 &dead_entries, flags); 4361 if (dead_entries != NULL) 4362 uvm_unmap_detach(dead_entries, 0); 4363 } 4364 KASSERT(map->nentries == 0); 4365 KASSERT(map->size == 0); 4366 4367 mutex_destroy(&map->misc_lock); 4368 rw_destroy(&map->lock); 4369 cv_destroy(&map->cv); 4370 pmap_destroy(map->pmap); 4371 pool_cache_put(&uvm_vmspace_cache, vm); 4372 } 4373 4374 static struct vm_map_entry * 4375 uvm_mapent_clone(struct vm_map *new_map, struct vm_map_entry *old_entry, 4376 int flags) 4377 { 4378 struct vm_map_entry *new_entry; 4379 4380 new_entry = uvm_mapent_alloc(new_map, 0); 4381 /* old_entry -> new_entry */ 4382 uvm_mapent_copy(old_entry, new_entry); 4383 4384 /* new pmap has nothing wired in it */ 4385 new_entry->wired_count = 0; 4386 4387 /* 4388 * gain reference to object backing the map (can't 4389 * be a submap, already checked this case). 4390 */ 4391 4392 if (new_entry->aref.ar_amap) 4393 uvm_map_reference_amap(new_entry, flags); 4394 4395 if (new_entry->object.uvm_obj && 4396 new_entry->object.uvm_obj->pgops->pgo_reference) 4397 new_entry->object.uvm_obj->pgops->pgo_reference( 4398 new_entry->object.uvm_obj); 4399 4400 /* insert entry at end of new_map's entry list */ 4401 uvm_map_entry_link(new_map, new_map->header.prev, 4402 new_entry); 4403 4404 return new_entry; 4405 } 4406 4407 /* 4408 * share the mapping: this means we want the old and 4409 * new entries to share amaps and backing objects. 4410 */ 4411 static void 4412 uvm_mapent_forkshared(struct vm_map *new_map, struct vm_map *old_map, 4413 struct vm_map_entry *old_entry) 4414 { 4415 /* 4416 * if the old_entry needs a new amap (due to prev fork) 4417 * then we need to allocate it now so that we have 4418 * something we own to share with the new_entry. [in 4419 * other words, we need to clear needs_copy] 4420 */ 4421 4422 if (UVM_ET_ISNEEDSCOPY(old_entry)) { 4423 /* get our own amap, clears needs_copy */ 4424 amap_copy(old_map, old_entry, AMAP_COPY_NOCHUNK, 4425 0, 0); 4426 /* XXXCDC: WAITOK??? */ 4427 } 4428 4429 uvm_mapent_clone(new_map, old_entry, AMAP_SHARED); 4430 } 4431 4432 4433 static void 4434 uvm_mapent_forkcopy(struct vm_map *new_map, struct vm_map *old_map, 4435 struct vm_map_entry *old_entry) 4436 { 4437 struct vm_map_entry *new_entry; 4438 4439 /* 4440 * copy-on-write the mapping (using mmap's 4441 * MAP_PRIVATE semantics) 4442 * 4443 * allocate new_entry, adjust reference counts. 4444 * (note that new references are read-only). 4445 */ 4446 4447 new_entry = uvm_mapent_clone(new_map, old_entry, 0); 4448 4449 new_entry->etype |= 4450 (UVM_ET_COPYONWRITE|UVM_ET_NEEDSCOPY); 4451 4452 /* 4453 * the new entry will need an amap. it will either 4454 * need to be copied from the old entry or created 4455 * from scratch (if the old entry does not have an 4456 * amap). can we defer this process until later 4457 * (by setting "needs_copy") or do we need to copy 4458 * the amap now? 4459 * 4460 * we must copy the amap now if any of the following 4461 * conditions hold: 4462 * 1. the old entry has an amap and that amap is 4463 * being shared. this means that the old (parent) 4464 * process is sharing the amap with another 4465 * process. if we do not clear needs_copy here 4466 * we will end up in a situation where both the 4467 * parent and child process are referring to the 4468 * same amap with "needs_copy" set. if the 4469 * parent write-faults, the fault routine will 4470 * clear "needs_copy" in the parent by allocating 4471 * a new amap. this is wrong because the 4472 * parent is supposed to be sharing the old amap 4473 * and the new amap will break that. 4474 * 4475 * 2. if the old entry has an amap and a non-zero 4476 * wire count then we are going to have to call 4477 * amap_cow_now to avoid page faults in the 4478 * parent process. since amap_cow_now requires 4479 * "needs_copy" to be clear we might as well 4480 * clear it here as well. 4481 * 4482 */ 4483 4484 if (old_entry->aref.ar_amap != NULL) { 4485 if ((amap_flags(old_entry->aref.ar_amap) & AMAP_SHARED) != 0 || 4486 VM_MAPENT_ISWIRED(old_entry)) { 4487 4488 amap_copy(new_map, new_entry, 4489 AMAP_COPY_NOCHUNK, 0, 0); 4490 /* XXXCDC: M_WAITOK ... ok? */ 4491 } 4492 } 4493 4494 /* 4495 * if the parent's entry is wired down, then the 4496 * parent process does not want page faults on 4497 * access to that memory. this means that we 4498 * cannot do copy-on-write because we can't write 4499 * protect the old entry. in this case we 4500 * resolve all copy-on-write faults now, using 4501 * amap_cow_now. note that we have already 4502 * allocated any needed amap (above). 4503 */ 4504 4505 if (VM_MAPENT_ISWIRED(old_entry)) { 4506 4507 /* 4508 * resolve all copy-on-write faults now 4509 * (note that there is nothing to do if 4510 * the old mapping does not have an amap). 4511 */ 4512 if (old_entry->aref.ar_amap) 4513 amap_cow_now(new_map, new_entry); 4514 4515 } else { 4516 /* 4517 * setup mappings to trigger copy-on-write faults 4518 * we must write-protect the parent if it has 4519 * an amap and it is not already "needs_copy"... 4520 * if it is already "needs_copy" then the parent 4521 * has already been write-protected by a previous 4522 * fork operation. 4523 */ 4524 if (old_entry->aref.ar_amap && 4525 !UVM_ET_ISNEEDSCOPY(old_entry)) { 4526 if (old_entry->max_protection & VM_PROT_WRITE) { 4527 #ifdef __HAVE_UNLOCKED_PMAP /* XXX temporary */ 4528 uvm_map_lock_entry(old_entry, RW_WRITER); 4529 #else 4530 uvm_map_lock_entry(old_entry, RW_READER); 4531 #endif 4532 pmap_protect(old_map->pmap, 4533 old_entry->start, old_entry->end, 4534 old_entry->protection & ~VM_PROT_WRITE); 4535 uvm_map_unlock_entry(old_entry); 4536 } 4537 old_entry->etype |= UVM_ET_NEEDSCOPY; 4538 } 4539 } 4540 } 4541 4542 /* 4543 * zero the mapping: the new entry will be zero initialized 4544 */ 4545 static void 4546 uvm_mapent_forkzero(struct vm_map *new_map, struct vm_map *old_map, 4547 struct vm_map_entry *old_entry) 4548 { 4549 struct vm_map_entry *new_entry; 4550 4551 new_entry = uvm_mapent_clone(new_map, old_entry, 0); 4552 4553 new_entry->etype |= 4554 (UVM_ET_COPYONWRITE|UVM_ET_NEEDSCOPY); 4555 4556 if (new_entry->aref.ar_amap) { 4557 uvm_map_unreference_amap(new_entry, 0); 4558 new_entry->aref.ar_pageoff = 0; 4559 new_entry->aref.ar_amap = NULL; 4560 } 4561 4562 if (UVM_ET_ISOBJ(new_entry)) { 4563 if (new_entry->object.uvm_obj->pgops->pgo_detach) 4564 new_entry->object.uvm_obj->pgops->pgo_detach( 4565 new_entry->object.uvm_obj); 4566 new_entry->object.uvm_obj = NULL; 4567 new_entry->offset = 0; 4568 new_entry->etype &= ~UVM_ET_OBJ; 4569 } 4570 } 4571 4572 /* 4573 * F O R K - m a i n e n t r y p o i n t 4574 */ 4575 /* 4576 * uvmspace_fork: fork a process' main map 4577 * 4578 * => create a new vmspace for child process from parent. 4579 * => parent's map must not be locked. 4580 */ 4581 4582 struct vmspace * 4583 uvmspace_fork(struct vmspace *vm1) 4584 { 4585 struct vmspace *vm2; 4586 struct vm_map *old_map = &vm1->vm_map; 4587 struct vm_map *new_map; 4588 struct vm_map_entry *old_entry; 4589 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 4590 4591 vm_map_lock(old_map); 4592 4593 vm2 = uvmspace_alloc(vm_map_min(old_map), vm_map_max(old_map), 4594 vm1->vm_map.flags & VM_MAP_TOPDOWN); 4595 memcpy(&vm2->vm_startcopy, &vm1->vm_startcopy, 4596 (char *) (vm1 + 1) - (char *) &vm1->vm_startcopy); 4597 new_map = &vm2->vm_map; /* XXX */ 4598 4599 old_entry = old_map->header.next; 4600 new_map->size = old_map->size; 4601 4602 /* 4603 * go entry-by-entry 4604 */ 4605 4606 while (old_entry != &old_map->header) { 4607 4608 /* 4609 * first, some sanity checks on the old entry 4610 */ 4611 4612 KASSERT(!UVM_ET_ISSUBMAP(old_entry)); 4613 KASSERT(UVM_ET_ISCOPYONWRITE(old_entry) || 4614 !UVM_ET_ISNEEDSCOPY(old_entry)); 4615 4616 switch (old_entry->inheritance) { 4617 case MAP_INHERIT_NONE: 4618 /* 4619 * drop the mapping, modify size 4620 */ 4621 new_map->size -= old_entry->end - old_entry->start; 4622 break; 4623 4624 case MAP_INHERIT_SHARE: 4625 uvm_mapent_forkshared(new_map, old_map, old_entry); 4626 break; 4627 4628 case MAP_INHERIT_COPY: 4629 uvm_mapent_forkcopy(new_map, old_map, old_entry); 4630 break; 4631 4632 case MAP_INHERIT_ZERO: 4633 uvm_mapent_forkzero(new_map, old_map, old_entry); 4634 break; 4635 default: 4636 KASSERT(0); 4637 break; 4638 } 4639 old_entry = old_entry->next; 4640 } 4641 4642 pmap_update(old_map->pmap); 4643 vm_map_unlock(old_map); 4644 4645 if (uvm_shmfork && vm1->vm_shm) 4646 (*uvm_shmfork)(vm1, vm2); 4647 4648 #ifdef PMAP_FORK 4649 pmap_fork(vm1->vm_map.pmap, vm2->vm_map.pmap); 4650 #endif 4651 4652 UVMHIST_LOG(maphist,"<- done",0,0,0,0); 4653 return (vm2); 4654 } 4655 4656 4657 /* 4658 * uvm_mapent_trymerge: try to merge an entry with its neighbors. 4659 * 4660 * => called with map locked. 4661 * => return non zero if successfully merged. 4662 */ 4663 4664 int 4665 uvm_mapent_trymerge(struct vm_map *map, struct vm_map_entry *entry, int flags) 4666 { 4667 struct uvm_object *uobj; 4668 struct vm_map_entry *next; 4669 struct vm_map_entry *prev; 4670 vsize_t size; 4671 int merged = 0; 4672 bool copying; 4673 int newetype; 4674 4675 if (entry->aref.ar_amap != NULL) { 4676 return 0; 4677 } 4678 if ((entry->flags & UVM_MAP_NOMERGE) != 0) { 4679 return 0; 4680 } 4681 4682 uobj = entry->object.uvm_obj; 4683 size = entry->end - entry->start; 4684 copying = (flags & UVM_MERGE_COPYING) != 0; 4685 newetype = copying ? (entry->etype & ~UVM_ET_NEEDSCOPY) : entry->etype; 4686 4687 next = entry->next; 4688 if (next != &map->header && 4689 next->start == entry->end && 4690 ((copying && next->aref.ar_amap != NULL && 4691 amap_refs(next->aref.ar_amap) == 1) || 4692 (!copying && next->aref.ar_amap == NULL)) && 4693 UVM_ET_ISCOMPATIBLE(next, newetype, 4694 uobj, entry->flags, entry->protection, 4695 entry->max_protection, entry->inheritance, entry->advice, 4696 entry->wired_count) && 4697 (uobj == NULL || entry->offset + size == next->offset)) { 4698 int error; 4699 4700 if (copying) { 4701 error = amap_extend(next, size, 4702 AMAP_EXTEND_NOWAIT|AMAP_EXTEND_BACKWARDS); 4703 } else { 4704 error = 0; 4705 } 4706 if (error == 0) { 4707 if (uobj) { 4708 if (uobj->pgops->pgo_detach) { 4709 uobj->pgops->pgo_detach(uobj); 4710 } 4711 } 4712 4713 entry->end = next->end; 4714 clear_hints(map, next); 4715 uvm_map_entry_unlink(map, next); 4716 if (copying) { 4717 entry->aref = next->aref; 4718 entry->etype &= ~UVM_ET_NEEDSCOPY; 4719 } 4720 uvm_map_check(map, "trymerge forwardmerge"); 4721 uvm_mapent_free(next); 4722 merged++; 4723 } 4724 } 4725 4726 prev = entry->prev; 4727 if (prev != &map->header && 4728 prev->end == entry->start && 4729 ((copying && !merged && prev->aref.ar_amap != NULL && 4730 amap_refs(prev->aref.ar_amap) == 1) || 4731 (!copying && prev->aref.ar_amap == NULL)) && 4732 UVM_ET_ISCOMPATIBLE(prev, newetype, 4733 uobj, entry->flags, entry->protection, 4734 entry->max_protection, entry->inheritance, entry->advice, 4735 entry->wired_count) && 4736 (uobj == NULL || 4737 prev->offset + prev->end - prev->start == entry->offset)) { 4738 int error; 4739 4740 if (copying) { 4741 error = amap_extend(prev, size, 4742 AMAP_EXTEND_NOWAIT|AMAP_EXTEND_FORWARDS); 4743 } else { 4744 error = 0; 4745 } 4746 if (error == 0) { 4747 if (uobj) { 4748 if (uobj->pgops->pgo_detach) { 4749 uobj->pgops->pgo_detach(uobj); 4750 } 4751 entry->offset = prev->offset; 4752 } 4753 4754 entry->start = prev->start; 4755 clear_hints(map, prev); 4756 uvm_map_entry_unlink(map, prev); 4757 if (copying) { 4758 entry->aref = prev->aref; 4759 entry->etype &= ~UVM_ET_NEEDSCOPY; 4760 } 4761 uvm_map_check(map, "trymerge backmerge"); 4762 uvm_mapent_free(prev); 4763 merged++; 4764 } 4765 } 4766 4767 return merged; 4768 } 4769 4770 /* 4771 * uvm_map_setup: init map 4772 * 4773 * => map must not be in service yet. 4774 */ 4775 4776 void 4777 uvm_map_setup(struct vm_map *map, vaddr_t vmin, vaddr_t vmax, int flags) 4778 { 4779 4780 rb_tree_init(&map->rb_tree, &uvm_map_tree_ops); 4781 map->header.next = map->header.prev = &map->header; 4782 map->nentries = 0; 4783 map->size = 0; 4784 map->ref_count = 1; 4785 vm_map_setmin(map, vmin); 4786 vm_map_setmax(map, vmax); 4787 map->flags = flags; 4788 map->first_free = &map->header; 4789 map->hint = &map->header; 4790 map->timestamp = 0; 4791 map->busy = NULL; 4792 4793 rw_init(&map->lock); 4794 cv_init(&map->cv, "vm_map"); 4795 mutex_init(&map->misc_lock, MUTEX_DRIVER, IPL_NONE); 4796 } 4797 4798 /* 4799 * U N M A P - m a i n e n t r y p o i n t 4800 */ 4801 4802 /* 4803 * uvm_unmap1: remove mappings from a vm_map (from "start" up to "stop") 4804 * 4805 * => caller must check alignment and size 4806 * => map must be unlocked (we will lock it) 4807 * => flags is UVM_FLAG_QUANTUM or 0. 4808 */ 4809 4810 void 4811 uvm_unmap1(struct vm_map *map, vaddr_t start, vaddr_t end, int flags) 4812 { 4813 struct vm_map_entry *dead_entries; 4814 UVMHIST_FUNC(__func__); 4815 UVMHIST_CALLARGS(maphist, " (map=%#jx, start=%#jx, end=%#jx)", 4816 (uintptr_t)map, start, end, 0); 4817 4818 KASSERTMSG(start < end, 4819 "%s: map %p: start %#jx < end %#jx", __func__, map, 4820 (uintmax_t)start, (uintmax_t)end); 4821 if (map == kernel_map) { 4822 LOCKDEBUG_MEM_CHECK((void *)start, end - start); 4823 } 4824 4825 /* 4826 * work now done by helper functions. wipe the pmap's and then 4827 * detach from the dead entries... 4828 */ 4829 vm_map_lock(map); 4830 uvm_unmap_remove(map, start, end, &dead_entries, flags); 4831 vm_map_unlock(map); 4832 4833 if (dead_entries != NULL) 4834 uvm_unmap_detach(dead_entries, 0); 4835 4836 UVMHIST_LOG(maphist, "<- done", 0,0,0,0); 4837 } 4838 4839 4840 /* 4841 * uvm_map_reference: add reference to a map 4842 * 4843 * => map need not be locked 4844 */ 4845 4846 void 4847 uvm_map_reference(struct vm_map *map) 4848 { 4849 4850 atomic_inc_uint(&map->ref_count); 4851 } 4852 4853 void 4854 uvm_map_lock_entry(struct vm_map_entry *entry, krw_t op) 4855 { 4856 4857 if (entry->aref.ar_amap != NULL) { 4858 amap_lock(entry->aref.ar_amap, op); 4859 } 4860 if (UVM_ET_ISOBJ(entry)) { 4861 rw_enter(entry->object.uvm_obj->vmobjlock, op); 4862 } 4863 } 4864 4865 void 4866 uvm_map_unlock_entry(struct vm_map_entry *entry) 4867 { 4868 4869 if (UVM_ET_ISOBJ(entry)) { 4870 rw_exit(entry->object.uvm_obj->vmobjlock); 4871 } 4872 if (entry->aref.ar_amap != NULL) { 4873 amap_unlock(entry->aref.ar_amap); 4874 } 4875 } 4876 4877 #define UVM_VOADDR_TYPE_MASK 0x3UL 4878 #define UVM_VOADDR_TYPE_UOBJ 0x1UL 4879 #define UVM_VOADDR_TYPE_ANON 0x2UL 4880 #define UVM_VOADDR_OBJECT_MASK ~UVM_VOADDR_TYPE_MASK 4881 4882 #define UVM_VOADDR_GET_TYPE(voa) \ 4883 ((voa)->object & UVM_VOADDR_TYPE_MASK) 4884 #define UVM_VOADDR_GET_OBJECT(voa) \ 4885 ((voa)->object & UVM_VOADDR_OBJECT_MASK) 4886 #define UVM_VOADDR_SET_OBJECT(voa, obj, type) \ 4887 do { \ 4888 KASSERT(((uintptr_t)(obj) & UVM_VOADDR_TYPE_MASK) == 0); \ 4889 (voa)->object = ((uintptr_t)(obj)) | (type); \ 4890 } while (/*CONSTCOND*/0) 4891 4892 #define UVM_VOADDR_GET_UOBJ(voa) \ 4893 ((struct uvm_object *)UVM_VOADDR_GET_OBJECT(voa)) 4894 #define UVM_VOADDR_SET_UOBJ(voa, uobj) \ 4895 UVM_VOADDR_SET_OBJECT(voa, uobj, UVM_VOADDR_TYPE_UOBJ) 4896 4897 #define UVM_VOADDR_GET_ANON(voa) \ 4898 ((struct vm_anon *)UVM_VOADDR_GET_OBJECT(voa)) 4899 #define UVM_VOADDR_SET_ANON(voa, anon) \ 4900 UVM_VOADDR_SET_OBJECT(voa, anon, UVM_VOADDR_TYPE_ANON) 4901 4902 /* 4903 * uvm_voaddr_acquire: returns the virtual object address corresponding 4904 * to the specified virtual address. 4905 * 4906 * => resolves COW so the true page identity is tracked. 4907 * 4908 * => acquires a reference on the page's owner (uvm_object or vm_anon) 4909 */ 4910 bool 4911 uvm_voaddr_acquire(struct vm_map * const map, vaddr_t const va, 4912 struct uvm_voaddr * const voaddr) 4913 { 4914 struct vm_map_entry *entry; 4915 struct vm_anon *anon = NULL; 4916 bool result = false; 4917 bool exclusive = false; 4918 void (*unlock_fn)(struct vm_map *); 4919 4920 UVMHIST_FUNC(__func__); UVMHIST_CALLED(maphist); 4921 UVMHIST_LOG(maphist,"(map=%#jx,va=%#jx)", (uintptr_t)map, va, 0, 0); 4922 4923 const vaddr_t start = trunc_page(va); 4924 const vaddr_t end = round_page(va+1); 4925 4926 lookup_again: 4927 if (__predict_false(exclusive)) { 4928 vm_map_lock(map); 4929 unlock_fn = vm_map_unlock; 4930 } else { 4931 vm_map_lock_read(map); 4932 unlock_fn = vm_map_unlock_read; 4933 } 4934 4935 if (__predict_false(!uvm_map_lookup_entry(map, start, &entry))) { 4936 unlock_fn(map); 4937 UVMHIST_LOG(maphist,"<- done (no entry)",0,0,0,0); 4938 return false; 4939 } 4940 4941 if (__predict_false(entry->protection == VM_PROT_NONE)) { 4942 unlock_fn(map); 4943 UVMHIST_LOG(maphist,"<- done (PROT_NONE)",0,0,0,0); 4944 return false; 4945 } 4946 4947 /* 4948 * We have a fast path for the common case of "no COW resolution 4949 * needed" whereby we have taken a read lock on the map and if 4950 * we don't encounter any need to create a vm_anon then great! 4951 * But if we do, we loop around again, instead taking an exclusive 4952 * lock so that we can perform the fault. 4953 * 4954 * In the event that we have to resolve the fault, we do nearly the 4955 * same work as uvm_map_pageable() does: 4956 * 4957 * 1: holding the write lock, we create any anonymous maps that need 4958 * to be created. however, we do NOT need to clip the map entries 4959 * in this case. 4960 * 4961 * 2: we downgrade to a read lock, and call uvm_fault_wire to fault 4962 * in the page (assuming the entry is not already wired). this 4963 * is done because we need the vm_anon to be present. 4964 */ 4965 if (__predict_true(!VM_MAPENT_ISWIRED(entry))) { 4966 4967 bool need_fault = false; 4968 4969 /* 4970 * perform the action of vm_map_lookup that need the 4971 * write lock on the map: create an anonymous map for 4972 * a copy-on-write region, or an anonymous map for 4973 * a zero-fill region. 4974 */ 4975 if (__predict_false(UVM_ET_ISSUBMAP(entry))) { 4976 unlock_fn(map); 4977 UVMHIST_LOG(maphist,"<- done (submap)",0,0,0,0); 4978 return false; 4979 } 4980 if (__predict_false(UVM_ET_ISNEEDSCOPY(entry) && 4981 ((entry->max_protection & VM_PROT_WRITE) || 4982 (entry->object.uvm_obj == NULL)))) { 4983 if (!exclusive) { 4984 /* need to take the slow path */ 4985 KASSERT(unlock_fn == vm_map_unlock_read); 4986 vm_map_unlock_read(map); 4987 exclusive = true; 4988 goto lookup_again; 4989 } 4990 need_fault = true; 4991 amap_copy(map, entry, 0, start, end); 4992 /* XXXCDC: wait OK? */ 4993 } 4994 4995 /* 4996 * do a quick check to see if the fault has already 4997 * been resolved to the upper layer. 4998 */ 4999 if (__predict_true(entry->aref.ar_amap != NULL && 5000 need_fault == false)) { 5001 amap_lock(entry->aref.ar_amap, RW_WRITER); 5002 anon = amap_lookup(&entry->aref, start - entry->start); 5003 if (__predict_true(anon != NULL)) { 5004 /* amap unlocked below */ 5005 goto found_anon; 5006 } 5007 amap_unlock(entry->aref.ar_amap); 5008 need_fault = true; 5009 } 5010 5011 /* 5012 * we predict this test as false because if we reach 5013 * this point, then we are likely dealing with a 5014 * shared memory region backed by a uvm_object, in 5015 * which case a fault to create the vm_anon is not 5016 * necessary. 5017 */ 5018 if (__predict_false(need_fault)) { 5019 if (exclusive) { 5020 vm_map_busy(map); 5021 vm_map_unlock(map); 5022 unlock_fn = vm_map_unbusy; 5023 } 5024 5025 if (uvm_fault_wire(map, start, end, 5026 entry->max_protection, 1)) { 5027 /* wiring failed */ 5028 unlock_fn(map); 5029 UVMHIST_LOG(maphist,"<- done (wire failed)", 5030 0,0,0,0); 5031 return false; 5032 } 5033 5034 /* 5035 * now that we have resolved the fault, we can unwire 5036 * the page. 5037 */ 5038 if (exclusive) { 5039 vm_map_lock(map); 5040 vm_map_unbusy(map); 5041 unlock_fn = vm_map_unlock; 5042 } 5043 5044 uvm_fault_unwire_locked(map, start, end); 5045 } 5046 } 5047 5048 /* check the upper layer */ 5049 if (entry->aref.ar_amap) { 5050 amap_lock(entry->aref.ar_amap, RW_WRITER); 5051 anon = amap_lookup(&entry->aref, start - entry->start); 5052 if (anon) { 5053 found_anon: KASSERT(anon->an_lock == entry->aref.ar_amap->am_lock); 5054 anon->an_ref++; 5055 rw_obj_hold(anon->an_lock); 5056 KASSERT(anon->an_ref != 0); 5057 UVM_VOADDR_SET_ANON(voaddr, anon); 5058 voaddr->offset = va & PAGE_MASK; 5059 result = true; 5060 } 5061 amap_unlock(entry->aref.ar_amap); 5062 } 5063 5064 /* check the lower layer */ 5065 if (!result && UVM_ET_ISOBJ(entry)) { 5066 struct uvm_object *uobj = entry->object.uvm_obj; 5067 5068 KASSERT(uobj != NULL); 5069 (*uobj->pgops->pgo_reference)(uobj); 5070 UVM_VOADDR_SET_UOBJ(voaddr, uobj); 5071 voaddr->offset = entry->offset + (va - entry->start); 5072 result = true; 5073 } 5074 5075 unlock_fn(map); 5076 5077 if (result) { 5078 UVMHIST_LOG(maphist, 5079 "<- done OK (type=%jd,owner=%#jx,offset=%#jx)", 5080 UVM_VOADDR_GET_TYPE(voaddr), 5081 UVM_VOADDR_GET_OBJECT(voaddr), 5082 voaddr->offset, 0); 5083 } else { 5084 UVMHIST_LOG(maphist,"<- done (failed)",0,0,0,0); 5085 } 5086 5087 return result; 5088 } 5089 5090 /* 5091 * uvm_voaddr_release: release the references held by the 5092 * vitual object address. 5093 */ 5094 void 5095 uvm_voaddr_release(struct uvm_voaddr * const voaddr) 5096 { 5097 5098 switch (UVM_VOADDR_GET_TYPE(voaddr)) { 5099 case UVM_VOADDR_TYPE_UOBJ: { 5100 struct uvm_object * const uobj = UVM_VOADDR_GET_UOBJ(voaddr); 5101 5102 KASSERT(uobj != NULL); 5103 KASSERT(uobj->pgops->pgo_detach != NULL); 5104 (*uobj->pgops->pgo_detach)(uobj); 5105 break; 5106 } 5107 case UVM_VOADDR_TYPE_ANON: { 5108 struct vm_anon * const anon = UVM_VOADDR_GET_ANON(voaddr); 5109 krwlock_t *lock; 5110 5111 KASSERT(anon != NULL); 5112 rw_enter((lock = anon->an_lock), RW_WRITER); 5113 KASSERT(anon->an_ref > 0); 5114 if (--anon->an_ref == 0) { 5115 uvm_anfree(anon); 5116 } 5117 rw_exit(lock); 5118 rw_obj_free(lock); 5119 break; 5120 } 5121 default: 5122 panic("uvm_voaddr_release: bad type"); 5123 } 5124 memset(voaddr, 0, sizeof(*voaddr)); 5125 } 5126 5127 /* 5128 * uvm_voaddr_compare: compare two uvm_voaddr objects. 5129 * 5130 * => memcmp() semantics 5131 */ 5132 int 5133 uvm_voaddr_compare(const struct uvm_voaddr * const voaddr1, 5134 const struct uvm_voaddr * const voaddr2) 5135 { 5136 const uintptr_t type1 = UVM_VOADDR_GET_TYPE(voaddr1); 5137 const uintptr_t type2 = UVM_VOADDR_GET_TYPE(voaddr2); 5138 5139 KASSERT(type1 == UVM_VOADDR_TYPE_UOBJ || 5140 type1 == UVM_VOADDR_TYPE_ANON); 5141 5142 KASSERT(type2 == UVM_VOADDR_TYPE_UOBJ || 5143 type2 == UVM_VOADDR_TYPE_ANON); 5144 5145 if (type1 < type2) 5146 return -1; 5147 if (type1 > type2) 5148 return 1; 5149 5150 const uintptr_t addr1 = UVM_VOADDR_GET_OBJECT(voaddr1); 5151 const uintptr_t addr2 = UVM_VOADDR_GET_OBJECT(voaddr2); 5152 5153 if (addr1 < addr2) 5154 return -1; 5155 if (addr1 > addr2) 5156 return 1; 5157 5158 if (voaddr1->offset < voaddr2->offset) 5159 return -1; 5160 if (voaddr1->offset > voaddr2->offset) 5161 return 1; 5162 5163 return 0; 5164 } 5165 5166 #if defined(DDB) || defined(DEBUGPRINT) 5167 5168 /* 5169 * uvm_map_printit: actually prints the map 5170 */ 5171 5172 void 5173 uvm_map_printit(struct vm_map *map, bool full, 5174 void (*pr)(const char *, ...)) 5175 { 5176 struct vm_map_entry *entry; 5177 5178 (*pr)("MAP %p: [%#lx->%#lx]\n", map, vm_map_min(map), 5179 vm_map_max(map)); 5180 (*pr)("\t#ent=%d, sz=%d, ref=%d, version=%d, flags=%#x\n", 5181 map->nentries, map->size, map->ref_count, map->timestamp, 5182 map->flags); 5183 (*pr)("\tpmap=%p(resident=%ld, wired=%ld)\n", map->pmap, 5184 pmap_resident_count(map->pmap), pmap_wired_count(map->pmap)); 5185 if (!full) 5186 return; 5187 for (entry = map->header.next; entry != &map->header; 5188 entry = entry->next) { 5189 (*pr)(" - %p: %#lx->%#lx: obj=%p/%#llx, amap=%p/%d\n", 5190 entry, entry->start, entry->end, entry->object.uvm_obj, 5191 (long long)entry->offset, entry->aref.ar_amap, 5192 entry->aref.ar_pageoff); 5193 (*pr)( 5194 "\tsubmap=%c, cow=%c, nc=%c, prot(max)=%d/%d, inh=%d, " 5195 "wc=%d, adv=%d%s\n", 5196 (entry->etype & UVM_ET_SUBMAP) ? 'T' : 'F', 5197 (entry->etype & UVM_ET_COPYONWRITE) ? 'T' : 'F', 5198 (entry->etype & UVM_ET_NEEDSCOPY) ? 'T' : 'F', 5199 entry->protection, entry->max_protection, 5200 entry->inheritance, entry->wired_count, entry->advice, 5201 entry == map->first_free ? " (first_free)" : ""); 5202 } 5203 } 5204 5205 void 5206 uvm_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 5207 { 5208 struct vm_map *map; 5209 5210 for (map = kernel_map;;) { 5211 struct vm_map_entry *entry; 5212 5213 if (!uvm_map_lookup_entry_bytree(map, (vaddr_t)addr, &entry)) { 5214 break; 5215 } 5216 (*pr)("%p is %p+%zu from VMMAP %p\n", 5217 (void *)addr, (void *)entry->start, 5218 (size_t)(addr - (uintptr_t)entry->start), map); 5219 if (!UVM_ET_ISSUBMAP(entry)) { 5220 break; 5221 } 5222 map = entry->object.sub_map; 5223 } 5224 } 5225 5226 #endif /* DDB || DEBUGPRINT */ 5227 5228 #ifndef __USER_VA0_IS_SAFE 5229 static int 5230 sysctl_user_va0_disable(SYSCTLFN_ARGS) 5231 { 5232 struct sysctlnode node; 5233 int t, error; 5234 5235 node = *rnode; 5236 node.sysctl_data = &t; 5237 t = user_va0_disable; 5238 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 5239 if (error || newp == NULL) 5240 return (error); 5241 5242 if (!t && user_va0_disable && 5243 kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_MAP_VA_ZERO, 0, 5244 NULL, NULL, NULL)) 5245 return EPERM; 5246 5247 user_va0_disable = !!t; 5248 return 0; 5249 } 5250 #endif 5251 5252 static int 5253 fill_vmentry(struct lwp *l, struct proc *p, struct kinfo_vmentry *kve, 5254 struct vm_map *m, struct vm_map_entry *e) 5255 { 5256 #ifndef _RUMPKERNEL 5257 int error; 5258 5259 memset(kve, 0, sizeof(*kve)); 5260 KASSERT(e != NULL); 5261 if (UVM_ET_ISOBJ(e)) { 5262 struct uvm_object *uobj = e->object.uvm_obj; 5263 KASSERT(uobj != NULL); 5264 kve->kve_ref_count = uobj->uo_refs; 5265 kve->kve_count = uobj->uo_npages; 5266 if (UVM_OBJ_IS_VNODE(uobj)) { 5267 struct vattr va; 5268 struct vnode *vp = (struct vnode *)uobj; 5269 vn_lock(vp, LK_SHARED | LK_RETRY); 5270 error = VOP_GETATTR(vp, &va, l->l_cred); 5271 VOP_UNLOCK(vp); 5272 kve->kve_type = KVME_TYPE_VNODE; 5273 if (error == 0) { 5274 kve->kve_vn_size = vp->v_size; 5275 kve->kve_vn_type = (int)vp->v_type; 5276 kve->kve_vn_mode = va.va_mode; 5277 kve->kve_vn_rdev = va.va_rdev; 5278 kve->kve_vn_fileid = va.va_fileid; 5279 kve->kve_vn_fsid = va.va_fsid; 5280 error = vnode_to_path(kve->kve_path, 5281 sizeof(kve->kve_path) / 2, vp, l, p); 5282 } 5283 } else if (UVM_OBJ_IS_KERN_OBJECT(uobj)) { 5284 kve->kve_type = KVME_TYPE_KERN; 5285 } else if (UVM_OBJ_IS_DEVICE(uobj)) { 5286 kve->kve_type = KVME_TYPE_DEVICE; 5287 } else if (UVM_OBJ_IS_AOBJ(uobj)) { 5288 kve->kve_type = KVME_TYPE_ANON; 5289 } else { 5290 kve->kve_type = KVME_TYPE_OBJECT; 5291 } 5292 } else if (UVM_ET_ISSUBMAP(e)) { 5293 struct vm_map *map = e->object.sub_map; 5294 KASSERT(map != NULL); 5295 kve->kve_ref_count = map->ref_count; 5296 kve->kve_count = map->nentries; 5297 kve->kve_type = KVME_TYPE_SUBMAP; 5298 } else 5299 kve->kve_type = KVME_TYPE_UNKNOWN; 5300 5301 kve->kve_start = e->start; 5302 kve->kve_end = e->end; 5303 kve->kve_offset = e->offset; 5304 kve->kve_wired_count = e->wired_count; 5305 kve->kve_inheritance = e->inheritance; 5306 kve->kve_attributes = 0; /* unused */ 5307 kve->kve_advice = e->advice; 5308 #define PROT(p) (((p) & VM_PROT_READ) ? KVME_PROT_READ : 0) | \ 5309 (((p) & VM_PROT_WRITE) ? KVME_PROT_WRITE : 0) | \ 5310 (((p) & VM_PROT_EXECUTE) ? KVME_PROT_EXEC : 0) 5311 kve->kve_protection = PROT(e->protection); 5312 kve->kve_max_protection = PROT(e->max_protection); 5313 kve->kve_flags |= (e->etype & UVM_ET_COPYONWRITE) 5314 ? KVME_FLAG_COW : 0; 5315 kve->kve_flags |= (e->etype & UVM_ET_NEEDSCOPY) 5316 ? KVME_FLAG_NEEDS_COPY : 0; 5317 kve->kve_flags |= (m->flags & VM_MAP_TOPDOWN) 5318 ? KVME_FLAG_GROWS_DOWN : KVME_FLAG_GROWS_UP; 5319 kve->kve_flags |= (m->flags & VM_MAP_PAGEABLE) 5320 ? KVME_FLAG_PAGEABLE : 0; 5321 #endif 5322 return 0; 5323 } 5324 5325 static int 5326 fill_vmentries(struct lwp *l, pid_t pid, u_int elem_size, void *oldp, 5327 size_t *oldlenp) 5328 { 5329 int error; 5330 struct proc *p; 5331 struct kinfo_vmentry *vme; 5332 struct vmspace *vm; 5333 struct vm_map *map; 5334 struct vm_map_entry *entry; 5335 char *dp; 5336 size_t count, vmesize; 5337 5338 if (elem_size == 0 || elem_size > 2 * sizeof(*vme)) 5339 return EINVAL; 5340 5341 if (oldp) { 5342 if (*oldlenp > 10UL * 1024UL * 1024UL) 5343 return E2BIG; 5344 count = *oldlenp / elem_size; 5345 if (count == 0) 5346 return ENOMEM; 5347 vmesize = count * sizeof(*vme); 5348 } else 5349 vmesize = 0; 5350 5351 if ((error = proc_find_locked(l, &p, pid)) != 0) 5352 return error; 5353 5354 vme = NULL; 5355 count = 0; 5356 5357 if ((error = proc_vmspace_getref(p, &vm)) != 0) 5358 goto out; 5359 5360 map = &vm->vm_map; 5361 vm_map_lock_read(map); 5362 5363 dp = oldp; 5364 if (oldp) 5365 vme = kmem_alloc(vmesize, KM_SLEEP); 5366 for (entry = map->header.next; entry != &map->header; 5367 entry = entry->next) { 5368 if (oldp && (dp - (char *)oldp) < vmesize) { 5369 error = fill_vmentry(l, p, &vme[count], map, entry); 5370 if (error) 5371 goto out; 5372 dp += elem_size; 5373 } 5374 count++; 5375 } 5376 vm_map_unlock_read(map); 5377 uvmspace_free(vm); 5378 5379 out: 5380 if (pid != -1) 5381 mutex_exit(p->p_lock); 5382 if (error == 0) { 5383 const u_int esize = uimin(sizeof(*vme), elem_size); 5384 dp = oldp; 5385 for (size_t i = 0; i < count; i++) { 5386 if (oldp && (dp - (char *)oldp) < vmesize) { 5387 error = sysctl_copyout(l, &vme[i], dp, esize); 5388 if (error) 5389 break; 5390 dp += elem_size; 5391 } else 5392 break; 5393 } 5394 count *= elem_size; 5395 if (oldp != NULL && *oldlenp < count) 5396 error = ENOSPC; 5397 *oldlenp = count; 5398 } 5399 if (vme) 5400 kmem_free(vme, vmesize); 5401 return error; 5402 } 5403 5404 static int 5405 sysctl_vmproc(SYSCTLFN_ARGS) 5406 { 5407 int error; 5408 5409 if (namelen == 1 && name[0] == CTL_QUERY) 5410 return (sysctl_query(SYSCTLFN_CALL(rnode))); 5411 5412 if (namelen == 0) 5413 return EINVAL; 5414 5415 switch (name[0]) { 5416 case VM_PROC_MAP: 5417 if (namelen != 3) 5418 return EINVAL; 5419 sysctl_unlock(); 5420 error = fill_vmentries(l, name[1], name[2], oldp, oldlenp); 5421 sysctl_relock(); 5422 return error; 5423 default: 5424 return EINVAL; 5425 } 5426 } 5427 5428 SYSCTL_SETUP(sysctl_uvmmap_setup, "sysctl uvmmap setup") 5429 { 5430 5431 sysctl_createv(clog, 0, NULL, NULL, 5432 CTLFLAG_PERMANENT, 5433 CTLTYPE_STRUCT, "proc", 5434 SYSCTL_DESCR("Process vm information"), 5435 sysctl_vmproc, 0, NULL, 0, 5436 CTL_VM, VM_PROC, CTL_EOL); 5437 #ifndef __USER_VA0_IS_SAFE 5438 sysctl_createv(clog, 0, NULL, NULL, 5439 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 5440 CTLTYPE_INT, "user_va0_disable", 5441 SYSCTL_DESCR("Disable VA 0"), 5442 sysctl_user_va0_disable, 0, &user_va0_disable, 0, 5443 CTL_VM, CTL_CREATE, CTL_EOL); 5444 #endif 5445 } 5446