1 /* $NetBSD: uvm_map.c,v 1.342 2016/12/01 02:09:03 mrg 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 1.342 2016/12/01 02:09:03 mrg Exp $"); 70 71 #include "opt_ddb.h" 72 #include "opt_uvmhist.h" 73 #include "opt_uvm.h" 74 #include "opt_sysv.h" 75 76 #include <sys/param.h> 77 #include <sys/systm.h> 78 #include <sys/mman.h> 79 #include <sys/proc.h> 80 #include <sys/pool.h> 81 #include <sys/kernel.h> 82 #include <sys/mount.h> 83 #include <sys/vnode.h> 84 #include <sys/filedesc.h> 85 #include <sys/lockdebug.h> 86 #include <sys/atomic.h> 87 #include <sys/sysctl.h> 88 #ifndef __USER_VA0_IS_SAFE 89 #include <sys/kauth.h> 90 #include "opt_user_va0_disable_default.h" 91 #endif 92 93 #include <sys/shm.h> 94 95 #include <uvm/uvm.h> 96 #include <uvm/uvm_readahead.h> 97 98 #if defined(DDB) || defined(DEBUGPRINT) 99 #include <uvm/uvm_ddb.h> 100 #endif 101 102 #ifdef UVMHIST 103 #ifndef UVMHIST_MAPHIST_SIZE 104 #define UVMHIST_MAPHIST_SIZE 100 105 #endif 106 #ifndef UVMHIST_PDHIST_SIZE 107 #define UVMHIST_PDHIST_SIZE 100 108 #endif 109 static struct kern_history_ent maphistbuf[UVMHIST_MAPHIST_SIZE]; 110 UVMHIST_DEFINE(maphist) = UVMHIST_INITIALIZER(maphist, maphistbuf); 111 #endif 112 113 #if !defined(UVMMAP_COUNTERS) 114 115 #define UVMMAP_EVCNT_DEFINE(name) /* nothing */ 116 #define UVMMAP_EVCNT_INCR(ev) /* nothing */ 117 #define UVMMAP_EVCNT_DECR(ev) /* nothing */ 118 119 #else /* defined(UVMMAP_NOCOUNTERS) */ 120 121 #include <sys/evcnt.h> 122 #define UVMMAP_EVCNT_DEFINE(name) \ 123 struct evcnt uvmmap_evcnt_##name = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, \ 124 "uvmmap", #name); \ 125 EVCNT_ATTACH_STATIC(uvmmap_evcnt_##name); 126 #define UVMMAP_EVCNT_INCR(ev) uvmmap_evcnt_##ev.ev_count++ 127 #define UVMMAP_EVCNT_DECR(ev) uvmmap_evcnt_##ev.ev_count-- 128 129 #endif /* defined(UVMMAP_NOCOUNTERS) */ 130 131 UVMMAP_EVCNT_DEFINE(ubackmerge) 132 UVMMAP_EVCNT_DEFINE(uforwmerge) 133 UVMMAP_EVCNT_DEFINE(ubimerge) 134 UVMMAP_EVCNT_DEFINE(unomerge) 135 UVMMAP_EVCNT_DEFINE(kbackmerge) 136 UVMMAP_EVCNT_DEFINE(kforwmerge) 137 UVMMAP_EVCNT_DEFINE(kbimerge) 138 UVMMAP_EVCNT_DEFINE(knomerge) 139 UVMMAP_EVCNT_DEFINE(map_call) 140 UVMMAP_EVCNT_DEFINE(mlk_call) 141 UVMMAP_EVCNT_DEFINE(mlk_hint) 142 UVMMAP_EVCNT_DEFINE(mlk_list) 143 UVMMAP_EVCNT_DEFINE(mlk_tree) 144 UVMMAP_EVCNT_DEFINE(mlk_treeloop) 145 UVMMAP_EVCNT_DEFINE(mlk_listloop) 146 147 const char vmmapbsy[] = "vmmapbsy"; 148 149 /* 150 * cache for vmspace structures. 151 */ 152 153 static struct pool_cache uvm_vmspace_cache; 154 155 /* 156 * cache for dynamically-allocated map entries. 157 */ 158 159 static struct pool_cache uvm_map_entry_cache; 160 161 #ifdef PMAP_GROWKERNEL 162 /* 163 * This global represents the end of the kernel virtual address 164 * space. If we want to exceed this, we must grow the kernel 165 * virtual address space dynamically. 166 * 167 * Note, this variable is locked by kernel_map's lock. 168 */ 169 vaddr_t uvm_maxkaddr; 170 #endif 171 172 #ifndef __USER_VA0_IS_SAFE 173 #ifndef __USER_VA0_DISABLE_DEFAULT 174 #define __USER_VA0_DISABLE_DEFAULT 1 175 #endif 176 #ifdef USER_VA0_DISABLE_DEFAULT /* kernel config option overrides */ 177 #undef __USER_VA0_DISABLE_DEFAULT 178 #define __USER_VA0_DISABLE_DEFAULT USER_VA0_DISABLE_DEFAULT 179 #endif 180 int user_va0_disable = __USER_VA0_DISABLE_DEFAULT; 181 #endif 182 183 /* 184 * macros 185 */ 186 187 /* 188 * UVM_ET_ISCOMPATIBLE: check some requirements for map entry merging 189 */ 190 extern struct vm_map *pager_map; 191 192 #define UVM_ET_ISCOMPATIBLE(ent, type, uobj, meflags, \ 193 prot, maxprot, inh, adv, wire) \ 194 ((ent)->etype == (type) && \ 195 (((ent)->flags ^ (meflags)) & (UVM_MAP_NOMERGE)) == 0 && \ 196 (ent)->object.uvm_obj == (uobj) && \ 197 (ent)->protection == (prot) && \ 198 (ent)->max_protection == (maxprot) && \ 199 (ent)->inheritance == (inh) && \ 200 (ent)->advice == (adv) && \ 201 (ent)->wired_count == (wire)) 202 203 /* 204 * uvm_map_entry_link: insert entry into a map 205 * 206 * => map must be locked 207 */ 208 #define uvm_map_entry_link(map, after_where, entry) do { \ 209 uvm_mapent_check(entry); \ 210 (map)->nentries++; \ 211 (entry)->prev = (after_where); \ 212 (entry)->next = (after_where)->next; \ 213 (entry)->prev->next = (entry); \ 214 (entry)->next->prev = (entry); \ 215 uvm_rb_insert((map), (entry)); \ 216 } while (/*CONSTCOND*/ 0) 217 218 /* 219 * uvm_map_entry_unlink: remove entry from a map 220 * 221 * => map must be locked 222 */ 223 #define uvm_map_entry_unlink(map, entry) do { \ 224 KASSERT((entry) != (map)->first_free); \ 225 KASSERT((entry) != (map)->hint); \ 226 uvm_mapent_check(entry); \ 227 (map)->nentries--; \ 228 (entry)->next->prev = (entry)->prev; \ 229 (entry)->prev->next = (entry)->next; \ 230 uvm_rb_remove((map), (entry)); \ 231 } while (/*CONSTCOND*/ 0) 232 233 /* 234 * SAVE_HINT: saves the specified entry as the hint for future lookups. 235 * 236 * => map need not be locked. 237 */ 238 #define SAVE_HINT(map, check, value) do { \ 239 if ((map)->hint == (check)) \ 240 (map)->hint = (value); \ 241 } while (/*CONSTCOND*/ 0) 242 243 /* 244 * clear_hints: ensure that hints don't point to the entry. 245 * 246 * => map must be write-locked. 247 */ 248 static void 249 clear_hints(struct vm_map *map, struct vm_map_entry *ent) 250 { 251 252 SAVE_HINT(map, ent, ent->prev); 253 if (map->first_free == ent) { 254 map->first_free = ent->prev; 255 } 256 } 257 258 /* 259 * VM_MAP_RANGE_CHECK: check and correct range 260 * 261 * => map must at least be read locked 262 */ 263 264 #define VM_MAP_RANGE_CHECK(map, start, end) do { \ 265 if (start < vm_map_min(map)) \ 266 start = vm_map_min(map); \ 267 if (end > vm_map_max(map)) \ 268 end = vm_map_max(map); \ 269 if (start > end) \ 270 start = end; \ 271 } while (/*CONSTCOND*/ 0) 272 273 /* 274 * local prototypes 275 */ 276 277 static struct vm_map_entry * 278 uvm_mapent_alloc(struct vm_map *, int); 279 static void uvm_mapent_copy(struct vm_map_entry *, struct vm_map_entry *); 280 static void uvm_mapent_free(struct vm_map_entry *); 281 #if defined(DEBUG) 282 static void _uvm_mapent_check(const struct vm_map_entry *, const char *, 283 int); 284 #define uvm_mapent_check(map) _uvm_mapent_check(map, __FILE__, __LINE__) 285 #else /* defined(DEBUG) */ 286 #define uvm_mapent_check(e) /* nothing */ 287 #endif /* defined(DEBUG) */ 288 289 static void uvm_map_entry_unwire(struct vm_map *, struct vm_map_entry *); 290 static void uvm_map_reference_amap(struct vm_map_entry *, int); 291 static int uvm_map_space_avail(vaddr_t *, vsize_t, voff_t, vsize_t, int, 292 int, struct vm_map_entry *); 293 static void uvm_map_unreference_amap(struct vm_map_entry *, int); 294 295 int _uvm_map_sanity(struct vm_map *); 296 int _uvm_tree_sanity(struct vm_map *); 297 static vsize_t uvm_rb_maxgap(const struct vm_map_entry *); 298 299 #define ROOT_ENTRY(map) ((struct vm_map_entry *)(map)->rb_tree.rbt_root) 300 #define LEFT_ENTRY(entry) ((struct vm_map_entry *)(entry)->rb_node.rb_left) 301 #define RIGHT_ENTRY(entry) ((struct vm_map_entry *)(entry)->rb_node.rb_right) 302 #define PARENT_ENTRY(map, entry) \ 303 (ROOT_ENTRY(map) == (entry) \ 304 ? NULL : (struct vm_map_entry *)RB_FATHER(&(entry)->rb_node)) 305 306 /* 307 * These get filled in if/when SYSVSHM shared memory code is loaded 308 * 309 * We do this with function pointers rather the #ifdef SYSVSHM so the 310 * SYSVSHM code can be loaded and unloaded 311 */ 312 void (*uvm_shmexit)(struct vmspace *) = NULL; 313 void (*uvm_shmfork)(struct vmspace *, struct vmspace *) = NULL; 314 315 static int 316 uvm_map_compare_nodes(void *ctx, const void *nparent, const void *nkey) 317 { 318 const struct vm_map_entry *eparent = nparent; 319 const struct vm_map_entry *ekey = nkey; 320 321 KASSERT(eparent->start < ekey->start || eparent->start >= ekey->end); 322 KASSERT(ekey->start < eparent->start || ekey->start >= eparent->end); 323 324 if (eparent->start < ekey->start) 325 return -1; 326 if (eparent->end >= ekey->start) 327 return 1; 328 return 0; 329 } 330 331 static int 332 uvm_map_compare_key(void *ctx, const void *nparent, const void *vkey) 333 { 334 const struct vm_map_entry *eparent = nparent; 335 const vaddr_t va = *(const vaddr_t *) vkey; 336 337 if (eparent->start < va) 338 return -1; 339 if (eparent->end >= va) 340 return 1; 341 return 0; 342 } 343 344 static const rb_tree_ops_t uvm_map_tree_ops = { 345 .rbto_compare_nodes = uvm_map_compare_nodes, 346 .rbto_compare_key = uvm_map_compare_key, 347 .rbto_node_offset = offsetof(struct vm_map_entry, rb_node), 348 .rbto_context = NULL 349 }; 350 351 /* 352 * uvm_rb_gap: return the gap size between our entry and next entry. 353 */ 354 static inline vsize_t 355 uvm_rb_gap(const struct vm_map_entry *entry) 356 { 357 358 KASSERT(entry->next != NULL); 359 return entry->next->start - entry->end; 360 } 361 362 static vsize_t 363 uvm_rb_maxgap(const struct vm_map_entry *entry) 364 { 365 struct vm_map_entry *child; 366 vsize_t maxgap = entry->gap; 367 368 /* 369 * We need maxgap to be the largest gap of us or any of our 370 * descendents. Since each of our children's maxgap is the 371 * cached value of their largest gap of themselves or their 372 * descendents, we can just use that value and avoid recursing 373 * down the tree to calculate it. 374 */ 375 if ((child = LEFT_ENTRY(entry)) != NULL && maxgap < child->maxgap) 376 maxgap = child->maxgap; 377 378 if ((child = RIGHT_ENTRY(entry)) != NULL && maxgap < child->maxgap) 379 maxgap = child->maxgap; 380 381 return maxgap; 382 } 383 384 static void 385 uvm_rb_fixup(struct vm_map *map, struct vm_map_entry *entry) 386 { 387 struct vm_map_entry *parent; 388 389 KASSERT(entry->gap == uvm_rb_gap(entry)); 390 entry->maxgap = uvm_rb_maxgap(entry); 391 392 while ((parent = PARENT_ENTRY(map, entry)) != NULL) { 393 struct vm_map_entry *brother; 394 vsize_t maxgap = parent->gap; 395 unsigned int which; 396 397 KDASSERT(parent->gap == uvm_rb_gap(parent)); 398 if (maxgap < entry->maxgap) 399 maxgap = entry->maxgap; 400 /* 401 * Since we work towards the root, we know entry's maxgap 402 * value is OK, but its brothers may now be out-of-date due 403 * to rebalancing. So refresh it. 404 */ 405 which = RB_POSITION(&entry->rb_node) ^ RB_DIR_OTHER; 406 brother = (struct vm_map_entry *)parent->rb_node.rb_nodes[which]; 407 if (brother != NULL) { 408 KDASSERT(brother->gap == uvm_rb_gap(brother)); 409 brother->maxgap = uvm_rb_maxgap(brother); 410 if (maxgap < brother->maxgap) 411 maxgap = brother->maxgap; 412 } 413 414 parent->maxgap = maxgap; 415 entry = parent; 416 } 417 } 418 419 static void 420 uvm_rb_insert(struct vm_map *map, struct vm_map_entry *entry) 421 { 422 struct vm_map_entry *ret __diagused; 423 424 entry->gap = entry->maxgap = uvm_rb_gap(entry); 425 if (entry->prev != &map->header) 426 entry->prev->gap = uvm_rb_gap(entry->prev); 427 428 ret = rb_tree_insert_node(&map->rb_tree, entry); 429 KASSERTMSG(ret == entry, 430 "uvm_rb_insert: map %p: duplicate entry %p", map, ret); 431 432 /* 433 * If the previous entry is not our immediate left child, then it's an 434 * ancestor and will be fixed up on the way to the root. We don't 435 * have to check entry->prev against &map->header since &map->header 436 * will never be in the tree. 437 */ 438 uvm_rb_fixup(map, 439 LEFT_ENTRY(entry) == entry->prev ? entry->prev : entry); 440 } 441 442 static void 443 uvm_rb_remove(struct vm_map *map, struct vm_map_entry *entry) 444 { 445 struct vm_map_entry *prev_parent = NULL, *next_parent = NULL; 446 447 /* 448 * If we are removing an interior node, then an adjacent node will 449 * be used to replace its position in the tree. Therefore we will 450 * need to fixup the tree starting at the parent of the replacement 451 * node. So record their parents for later use. 452 */ 453 if (entry->prev != &map->header) 454 prev_parent = PARENT_ENTRY(map, entry->prev); 455 if (entry->next != &map->header) 456 next_parent = PARENT_ENTRY(map, entry->next); 457 458 rb_tree_remove_node(&map->rb_tree, entry); 459 460 /* 461 * If the previous node has a new parent, fixup the tree starting 462 * at the previous node's old parent. 463 */ 464 if (entry->prev != &map->header) { 465 /* 466 * Update the previous entry's gap due to our absence. 467 */ 468 entry->prev->gap = uvm_rb_gap(entry->prev); 469 uvm_rb_fixup(map, entry->prev); 470 if (prev_parent != NULL 471 && prev_parent != entry 472 && prev_parent != PARENT_ENTRY(map, entry->prev)) 473 uvm_rb_fixup(map, prev_parent); 474 } 475 476 /* 477 * If the next node has a new parent, fixup the tree starting 478 * at the next node's old parent. 479 */ 480 if (entry->next != &map->header) { 481 uvm_rb_fixup(map, entry->next); 482 if (next_parent != NULL 483 && next_parent != entry 484 && next_parent != PARENT_ENTRY(map, entry->next)) 485 uvm_rb_fixup(map, next_parent); 486 } 487 } 488 489 #if defined(DEBUG) 490 int uvm_debug_check_map = 0; 491 int uvm_debug_check_rbtree = 0; 492 #define uvm_map_check(map, name) \ 493 _uvm_map_check((map), (name), __FILE__, __LINE__) 494 static void 495 _uvm_map_check(struct vm_map *map, const char *name, 496 const char *file, int line) 497 { 498 499 if ((uvm_debug_check_map && _uvm_map_sanity(map)) || 500 (uvm_debug_check_rbtree && _uvm_tree_sanity(map))) { 501 panic("uvm_map_check failed: \"%s\" map=%p (%s:%d)", 502 name, map, file, line); 503 } 504 } 505 #else /* defined(DEBUG) */ 506 #define uvm_map_check(map, name) /* nothing */ 507 #endif /* defined(DEBUG) */ 508 509 #if defined(DEBUG) || defined(DDB) 510 int 511 _uvm_map_sanity(struct vm_map *map) 512 { 513 bool first_free_found = false; 514 bool hint_found = false; 515 const struct vm_map_entry *e; 516 struct vm_map_entry *hint = map->hint; 517 518 e = &map->header; 519 for (;;) { 520 if (map->first_free == e) { 521 first_free_found = true; 522 } else if (!first_free_found && e->next->start > e->end) { 523 printf("first_free %p should be %p\n", 524 map->first_free, e); 525 return -1; 526 } 527 if (hint == e) { 528 hint_found = true; 529 } 530 531 e = e->next; 532 if (e == &map->header) { 533 break; 534 } 535 } 536 if (!first_free_found) { 537 printf("stale first_free\n"); 538 return -1; 539 } 540 if (!hint_found) { 541 printf("stale hint\n"); 542 return -1; 543 } 544 return 0; 545 } 546 547 int 548 _uvm_tree_sanity(struct vm_map *map) 549 { 550 struct vm_map_entry *tmp, *trtmp; 551 int n = 0, i = 1; 552 553 for (tmp = map->header.next; tmp != &map->header; tmp = tmp->next) { 554 if (tmp->gap != uvm_rb_gap(tmp)) { 555 printf("%d/%d gap %#lx != %#lx %s\n", 556 n + 1, map->nentries, 557 (ulong)tmp->gap, (ulong)uvm_rb_gap(tmp), 558 tmp->next == &map->header ? "(last)" : ""); 559 goto error; 560 } 561 /* 562 * If any entries are out of order, tmp->gap will be unsigned 563 * and will likely exceed the size of the map. 564 */ 565 if (tmp->gap >= vm_map_max(map) - vm_map_min(map)) { 566 printf("too large gap %zu\n", (size_t)tmp->gap); 567 goto error; 568 } 569 n++; 570 } 571 572 if (n != map->nentries) { 573 printf("nentries: %d vs %d\n", n, map->nentries); 574 goto error; 575 } 576 577 trtmp = NULL; 578 for (tmp = map->header.next; tmp != &map->header; tmp = tmp->next) { 579 if (tmp->maxgap != uvm_rb_maxgap(tmp)) { 580 printf("maxgap %#lx != %#lx\n", 581 (ulong)tmp->maxgap, 582 (ulong)uvm_rb_maxgap(tmp)); 583 goto error; 584 } 585 if (trtmp != NULL && trtmp->start >= tmp->start) { 586 printf("corrupt: 0x%"PRIxVADDR"x >= 0x%"PRIxVADDR"x\n", 587 trtmp->start, tmp->start); 588 goto error; 589 } 590 591 trtmp = tmp; 592 } 593 594 for (tmp = map->header.next; tmp != &map->header; 595 tmp = tmp->next, i++) { 596 trtmp = rb_tree_iterate(&map->rb_tree, tmp, RB_DIR_LEFT); 597 if (trtmp == NULL) 598 trtmp = &map->header; 599 if (tmp->prev != trtmp) { 600 printf("lookup: %d: %p->prev=%p: %p\n", 601 i, tmp, tmp->prev, trtmp); 602 goto error; 603 } 604 trtmp = rb_tree_iterate(&map->rb_tree, tmp, RB_DIR_RIGHT); 605 if (trtmp == NULL) 606 trtmp = &map->header; 607 if (tmp->next != trtmp) { 608 printf("lookup: %d: %p->next=%p: %p\n", 609 i, tmp, tmp->next, trtmp); 610 goto error; 611 } 612 trtmp = rb_tree_find_node(&map->rb_tree, &tmp->start); 613 if (trtmp != tmp) { 614 printf("lookup: %d: %p - %p: %p\n", i, tmp, trtmp, 615 PARENT_ENTRY(map, tmp)); 616 goto error; 617 } 618 } 619 620 return (0); 621 error: 622 return (-1); 623 } 624 #endif /* defined(DEBUG) || defined(DDB) */ 625 626 /* 627 * vm_map_lock: acquire an exclusive (write) lock on a map. 628 * 629 * => The locking protocol provides for guaranteed upgrade from shared -> 630 * exclusive by whichever thread currently has the map marked busy. 631 * See "LOCKING PROTOCOL NOTES" in uvm_map.h. This is horrible; among 632 * other problems, it defeats any fairness guarantees provided by RW 633 * locks. 634 */ 635 636 void 637 vm_map_lock(struct vm_map *map) 638 { 639 640 for (;;) { 641 rw_enter(&map->lock, RW_WRITER); 642 if (map->busy == NULL || map->busy == curlwp) { 643 break; 644 } 645 mutex_enter(&map->misc_lock); 646 rw_exit(&map->lock); 647 if (map->busy != NULL) { 648 cv_wait(&map->cv, &map->misc_lock); 649 } 650 mutex_exit(&map->misc_lock); 651 } 652 map->timestamp++; 653 } 654 655 /* 656 * vm_map_lock_try: try to lock a map, failing if it is already locked. 657 */ 658 659 bool 660 vm_map_lock_try(struct vm_map *map) 661 { 662 663 if (!rw_tryenter(&map->lock, RW_WRITER)) { 664 return false; 665 } 666 if (map->busy != NULL) { 667 rw_exit(&map->lock); 668 return false; 669 } 670 map->timestamp++; 671 return true; 672 } 673 674 /* 675 * vm_map_unlock: release an exclusive lock on a map. 676 */ 677 678 void 679 vm_map_unlock(struct vm_map *map) 680 { 681 682 KASSERT(rw_write_held(&map->lock)); 683 KASSERT(map->busy == NULL || map->busy == curlwp); 684 rw_exit(&map->lock); 685 } 686 687 /* 688 * vm_map_unbusy: mark the map as unbusy, and wake any waiters that 689 * want an exclusive lock. 690 */ 691 692 void 693 vm_map_unbusy(struct vm_map *map) 694 { 695 696 KASSERT(map->busy == curlwp); 697 698 /* 699 * Safe to clear 'busy' and 'waiters' with only a read lock held: 700 * 701 * o they can only be set with a write lock held 702 * o writers are blocked out with a read or write hold 703 * o at any time, only one thread owns the set of values 704 */ 705 mutex_enter(&map->misc_lock); 706 map->busy = NULL; 707 cv_broadcast(&map->cv); 708 mutex_exit(&map->misc_lock); 709 } 710 711 /* 712 * vm_map_lock_read: acquire a shared (read) lock on a map. 713 */ 714 715 void 716 vm_map_lock_read(struct vm_map *map) 717 { 718 719 rw_enter(&map->lock, RW_READER); 720 } 721 722 /* 723 * vm_map_unlock_read: release a shared lock on a map. 724 */ 725 726 void 727 vm_map_unlock_read(struct vm_map *map) 728 { 729 730 rw_exit(&map->lock); 731 } 732 733 /* 734 * vm_map_busy: mark a map as busy. 735 * 736 * => the caller must hold the map write locked 737 */ 738 739 void 740 vm_map_busy(struct vm_map *map) 741 { 742 743 KASSERT(rw_write_held(&map->lock)); 744 KASSERT(map->busy == NULL); 745 746 map->busy = curlwp; 747 } 748 749 /* 750 * vm_map_locked_p: return true if the map is write locked. 751 * 752 * => only for debug purposes like KASSERTs. 753 * => should not be used to verify that a map is not locked. 754 */ 755 756 bool 757 vm_map_locked_p(struct vm_map *map) 758 { 759 760 return rw_write_held(&map->lock); 761 } 762 763 /* 764 * uvm_mapent_alloc: allocate a map entry 765 */ 766 767 static struct vm_map_entry * 768 uvm_mapent_alloc(struct vm_map *map, int flags) 769 { 770 struct vm_map_entry *me; 771 int pflags = (flags & UVM_FLAG_NOWAIT) ? PR_NOWAIT : PR_WAITOK; 772 UVMHIST_FUNC("uvm_mapent_alloc"); UVMHIST_CALLED(maphist); 773 774 me = pool_cache_get(&uvm_map_entry_cache, pflags); 775 if (__predict_false(me == NULL)) { 776 return NULL; 777 } 778 me->flags = 0; 779 780 UVMHIST_LOG(maphist, "<- new entry=%p [kentry=%d]", me, 781 (map == kernel_map), 0, 0); 782 return me; 783 } 784 785 /* 786 * uvm_mapent_free: free map entry 787 */ 788 789 static void 790 uvm_mapent_free(struct vm_map_entry *me) 791 { 792 UVMHIST_FUNC("uvm_mapent_free"); UVMHIST_CALLED(maphist); 793 794 UVMHIST_LOG(maphist,"<- freeing map entry=%p [flags=%d]", 795 me, me->flags, 0, 0); 796 pool_cache_put(&uvm_map_entry_cache, me); 797 } 798 799 /* 800 * uvm_mapent_copy: copy a map entry, preserving flags 801 */ 802 803 static inline void 804 uvm_mapent_copy(struct vm_map_entry *src, struct vm_map_entry *dst) 805 { 806 807 memcpy(dst, src, ((char *)&src->uvm_map_entry_stop_copy) - 808 ((char *)src)); 809 } 810 811 #if defined(DEBUG) 812 static void 813 _uvm_mapent_check(const struct vm_map_entry *entry, const char *file, int line) 814 { 815 816 if (entry->start >= entry->end) { 817 goto bad; 818 } 819 if (UVM_ET_ISOBJ(entry)) { 820 if (entry->object.uvm_obj == NULL) { 821 goto bad; 822 } 823 } else if (UVM_ET_ISSUBMAP(entry)) { 824 if (entry->object.sub_map == NULL) { 825 goto bad; 826 } 827 } else { 828 if (entry->object.uvm_obj != NULL || 829 entry->object.sub_map != NULL) { 830 goto bad; 831 } 832 } 833 if (!UVM_ET_ISOBJ(entry)) { 834 if (entry->offset != 0) { 835 goto bad; 836 } 837 } 838 839 return; 840 841 bad: 842 panic("%s: bad entry %p (%s:%d)", __func__, entry, file, line); 843 } 844 #endif /* defined(DEBUG) */ 845 846 /* 847 * uvm_map_entry_unwire: unwire a map entry 848 * 849 * => map should be locked by caller 850 */ 851 852 static inline void 853 uvm_map_entry_unwire(struct vm_map *map, struct vm_map_entry *entry) 854 { 855 856 entry->wired_count = 0; 857 uvm_fault_unwire_locked(map, entry->start, entry->end); 858 } 859 860 861 /* 862 * wrapper for calling amap_ref() 863 */ 864 static inline void 865 uvm_map_reference_amap(struct vm_map_entry *entry, int flags) 866 { 867 868 amap_ref(entry->aref.ar_amap, entry->aref.ar_pageoff, 869 (entry->end - entry->start) >> PAGE_SHIFT, flags); 870 } 871 872 873 /* 874 * wrapper for calling amap_unref() 875 */ 876 static inline void 877 uvm_map_unreference_amap(struct vm_map_entry *entry, int flags) 878 { 879 880 amap_unref(entry->aref.ar_amap, entry->aref.ar_pageoff, 881 (entry->end - entry->start) >> PAGE_SHIFT, flags); 882 } 883 884 885 /* 886 * uvm_map_init: init mapping system at boot time. 887 */ 888 889 void 890 uvm_map_init(void) 891 { 892 #if defined(UVMHIST) 893 static struct kern_history_ent pdhistbuf[UVMHIST_PDHIST_SIZE]; 894 #endif 895 896 /* 897 * first, init logging system. 898 */ 899 900 UVMHIST_FUNC("uvm_map_init"); 901 UVMHIST_LINK_STATIC(maphist); 902 UVMHIST_INIT_STATIC(pdhist, pdhistbuf); 903 UVMHIST_CALLED(maphist); 904 UVMHIST_LOG(maphist,"<starting uvm map system>", 0, 0, 0, 0); 905 906 /* 907 * initialize the global lock for kernel map entry. 908 */ 909 910 mutex_init(&uvm_kentry_lock, MUTEX_DRIVER, IPL_VM); 911 } 912 913 /* 914 * uvm_map_init_caches: init mapping system caches. 915 */ 916 void 917 uvm_map_init_caches(void) 918 { 919 /* 920 * initialize caches. 921 */ 922 923 pool_cache_bootstrap(&uvm_map_entry_cache, sizeof(struct vm_map_entry), 924 0, 0, 0, "vmmpepl", NULL, IPL_NONE, NULL, NULL, NULL); 925 pool_cache_bootstrap(&uvm_vmspace_cache, sizeof(struct vmspace), 926 0, 0, 0, "vmsppl", NULL, IPL_NONE, NULL, NULL, NULL); 927 } 928 929 /* 930 * clippers 931 */ 932 933 /* 934 * uvm_mapent_splitadj: adjust map entries for splitting, after uvm_mapent_copy. 935 */ 936 937 static void 938 uvm_mapent_splitadj(struct vm_map_entry *entry1, struct vm_map_entry *entry2, 939 vaddr_t splitat) 940 { 941 vaddr_t adj; 942 943 KASSERT(entry1->start < splitat); 944 KASSERT(splitat < entry1->end); 945 946 adj = splitat - entry1->start; 947 entry1->end = entry2->start = splitat; 948 949 if (entry1->aref.ar_amap) { 950 amap_splitref(&entry1->aref, &entry2->aref, adj); 951 } 952 if (UVM_ET_ISSUBMAP(entry1)) { 953 /* ... unlikely to happen, but play it safe */ 954 uvm_map_reference(entry1->object.sub_map); 955 } else if (UVM_ET_ISOBJ(entry1)) { 956 KASSERT(entry1->object.uvm_obj != NULL); /* suppress coverity */ 957 entry2->offset += adj; 958 if (entry1->object.uvm_obj->pgops && 959 entry1->object.uvm_obj->pgops->pgo_reference) 960 entry1->object.uvm_obj->pgops->pgo_reference( 961 entry1->object.uvm_obj); 962 } 963 } 964 965 /* 966 * uvm_map_clip_start: ensure that the entry begins at or after 967 * the starting address, if it doesn't we split the entry. 968 * 969 * => caller should use UVM_MAP_CLIP_START macro rather than calling 970 * this directly 971 * => map must be locked by caller 972 */ 973 974 void 975 uvm_map_clip_start(struct vm_map *map, struct vm_map_entry *entry, 976 vaddr_t start) 977 { 978 struct vm_map_entry *new_entry; 979 980 /* uvm_map_simplify_entry(map, entry); */ /* XXX */ 981 982 uvm_map_check(map, "clip_start entry"); 983 uvm_mapent_check(entry); 984 985 /* 986 * Split off the front portion. note that we must insert the new 987 * entry BEFORE this one, so that this entry has the specified 988 * starting address. 989 */ 990 new_entry = uvm_mapent_alloc(map, 0); 991 uvm_mapent_copy(entry, new_entry); /* entry -> new_entry */ 992 uvm_mapent_splitadj(new_entry, entry, start); 993 uvm_map_entry_link(map, entry->prev, new_entry); 994 995 uvm_map_check(map, "clip_start leave"); 996 } 997 998 /* 999 * uvm_map_clip_end: ensure that the entry ends at or before 1000 * the ending address, if it does't we split the reference 1001 * 1002 * => caller should use UVM_MAP_CLIP_END macro rather than calling 1003 * this directly 1004 * => map must be locked by caller 1005 */ 1006 1007 void 1008 uvm_map_clip_end(struct vm_map *map, struct vm_map_entry *entry, vaddr_t end) 1009 { 1010 struct vm_map_entry *new_entry; 1011 1012 uvm_map_check(map, "clip_end entry"); 1013 uvm_mapent_check(entry); 1014 1015 /* 1016 * Create a new entry and insert it 1017 * AFTER the specified entry 1018 */ 1019 new_entry = uvm_mapent_alloc(map, 0); 1020 uvm_mapent_copy(entry, new_entry); /* entry -> new_entry */ 1021 uvm_mapent_splitadj(entry, new_entry, end); 1022 uvm_map_entry_link(map, entry, new_entry); 1023 1024 uvm_map_check(map, "clip_end leave"); 1025 } 1026 1027 /* 1028 * M A P - m a i n e n t r y p o i n t 1029 */ 1030 /* 1031 * uvm_map: establish a valid mapping in a map 1032 * 1033 * => assume startp is page aligned. 1034 * => assume size is a multiple of PAGE_SIZE. 1035 * => assume sys_mmap provides enough of a "hint" to have us skip 1036 * over text/data/bss area. 1037 * => map must be unlocked (we will lock it) 1038 * => <uobj,uoffset> value meanings (4 cases): 1039 * [1] <NULL,uoffset> == uoffset is a hint for PMAP_PREFER 1040 * [2] <NULL,UVM_UNKNOWN_OFFSET> == don't PMAP_PREFER 1041 * [3] <uobj,uoffset> == normal mapping 1042 * [4] <uobj,UVM_UNKNOWN_OFFSET> == uvm_map finds offset based on VA 1043 * 1044 * case [4] is for kernel mappings where we don't know the offset until 1045 * we've found a virtual address. note that kernel object offsets are 1046 * always relative to vm_map_min(kernel_map). 1047 * 1048 * => if `align' is non-zero, we align the virtual address to the specified 1049 * alignment. 1050 * this is provided as a mechanism for large pages. 1051 * 1052 * => XXXCDC: need way to map in external amap? 1053 */ 1054 1055 int 1056 uvm_map(struct vm_map *map, vaddr_t *startp /* IN/OUT */, vsize_t size, 1057 struct uvm_object *uobj, voff_t uoffset, vsize_t align, uvm_flag_t flags) 1058 { 1059 struct uvm_map_args args; 1060 struct vm_map_entry *new_entry; 1061 int error; 1062 1063 KASSERT((size & PAGE_MASK) == 0); 1064 1065 #ifndef __USER_VA0_IS_SAFE 1066 if ((flags & UVM_FLAG_FIXED) && *startp == 0 && 1067 !VM_MAP_IS_KERNEL(map) && user_va0_disable) 1068 return EACCES; 1069 #endif 1070 1071 /* 1072 * for pager_map, allocate the new entry first to avoid sleeping 1073 * for memory while we have the map locked. 1074 */ 1075 1076 new_entry = NULL; 1077 if (map == pager_map) { 1078 new_entry = uvm_mapent_alloc(map, (flags & UVM_FLAG_NOWAIT)); 1079 if (__predict_false(new_entry == NULL)) 1080 return ENOMEM; 1081 } 1082 if (map == pager_map) 1083 flags |= UVM_FLAG_NOMERGE; 1084 1085 error = uvm_map_prepare(map, *startp, size, uobj, uoffset, align, 1086 flags, &args); 1087 if (!error) { 1088 error = uvm_map_enter(map, &args, new_entry); 1089 *startp = args.uma_start; 1090 } else if (new_entry) { 1091 uvm_mapent_free(new_entry); 1092 } 1093 1094 #if defined(DEBUG) 1095 if (!error && VM_MAP_IS_KERNEL(map) && (flags & UVM_FLAG_NOWAIT) == 0) { 1096 uvm_km_check_empty(map, *startp, *startp + size); 1097 } 1098 #endif /* defined(DEBUG) */ 1099 1100 return error; 1101 } 1102 1103 /* 1104 * uvm_map_prepare: 1105 * 1106 * called with map unlocked. 1107 * on success, returns the map locked. 1108 */ 1109 1110 int 1111 uvm_map_prepare(struct vm_map *map, vaddr_t start, vsize_t size, 1112 struct uvm_object *uobj, voff_t uoffset, vsize_t align, uvm_flag_t flags, 1113 struct uvm_map_args *args) 1114 { 1115 struct vm_map_entry *prev_entry; 1116 vm_prot_t prot = UVM_PROTECTION(flags); 1117 vm_prot_t maxprot = UVM_MAXPROTECTION(flags); 1118 1119 UVMHIST_FUNC("uvm_map_prepare"); 1120 UVMHIST_CALLED(maphist); 1121 1122 UVMHIST_LOG(maphist, "(map=%p, start=%#lx, size=%lu, flags=%#x)", 1123 map, start, size, flags); 1124 UVMHIST_LOG(maphist, " uobj/offset %p/%ld", uobj, uoffset,0,0); 1125 1126 /* 1127 * detect a popular device driver bug. 1128 */ 1129 1130 KASSERT(doing_shutdown || curlwp != NULL); 1131 1132 /* 1133 * zero-sized mapping doesn't make any sense. 1134 */ 1135 KASSERT(size > 0); 1136 1137 KASSERT((~flags & (UVM_FLAG_NOWAIT | UVM_FLAG_WAITVA)) != 0); 1138 1139 uvm_map_check(map, "map entry"); 1140 1141 /* 1142 * check sanity of protection code 1143 */ 1144 1145 if ((prot & maxprot) != prot) { 1146 UVMHIST_LOG(maphist, "<- prot. failure: prot=%#x, max=%#x", 1147 prot, maxprot,0,0); 1148 return EACCES; 1149 } 1150 1151 /* 1152 * figure out where to put new VM range 1153 */ 1154 retry: 1155 if (vm_map_lock_try(map) == false) { 1156 if ((flags & UVM_FLAG_TRYLOCK) != 0) { 1157 return EAGAIN; 1158 } 1159 vm_map_lock(map); /* could sleep here */ 1160 } 1161 prev_entry = uvm_map_findspace(map, start, size, &start, 1162 uobj, uoffset, align, flags); 1163 if (prev_entry == NULL) { 1164 unsigned int timestamp; 1165 1166 timestamp = map->timestamp; 1167 UVMHIST_LOG(maphist,"waiting va timestamp=%#x", 1168 timestamp,0,0,0); 1169 map->flags |= VM_MAP_WANTVA; 1170 vm_map_unlock(map); 1171 1172 /* 1173 * try to reclaim kva and wait until someone does unmap. 1174 * fragile locking here, so we awaken every second to 1175 * recheck the condition. 1176 */ 1177 1178 mutex_enter(&map->misc_lock); 1179 while ((map->flags & VM_MAP_WANTVA) != 0 && 1180 map->timestamp == timestamp) { 1181 if ((flags & UVM_FLAG_WAITVA) == 0) { 1182 mutex_exit(&map->misc_lock); 1183 UVMHIST_LOG(maphist, 1184 "<- uvm_map_findspace failed!", 0,0,0,0); 1185 return ENOMEM; 1186 } else { 1187 cv_timedwait(&map->cv, &map->misc_lock, hz); 1188 } 1189 } 1190 mutex_exit(&map->misc_lock); 1191 goto retry; 1192 } 1193 1194 #ifdef PMAP_GROWKERNEL 1195 /* 1196 * If the kernel pmap can't map the requested space, 1197 * then allocate more resources for it. 1198 */ 1199 if (map == kernel_map && uvm_maxkaddr < (start + size)) 1200 uvm_maxkaddr = pmap_growkernel(start + size); 1201 #endif 1202 1203 UVMMAP_EVCNT_INCR(map_call); 1204 1205 /* 1206 * if uobj is null, then uoffset is either a VAC hint for PMAP_PREFER 1207 * [typically from uvm_map_reserve] or it is UVM_UNKNOWN_OFFSET. in 1208 * either case we want to zero it before storing it in the map entry 1209 * (because it looks strange and confusing when debugging...) 1210 * 1211 * if uobj is not null 1212 * if uoffset is not UVM_UNKNOWN_OFFSET then we have a normal mapping 1213 * and we do not need to change uoffset. 1214 * if uoffset is UVM_UNKNOWN_OFFSET then we need to find the offset 1215 * now (based on the starting address of the map). this case is 1216 * for kernel object mappings where we don't know the offset until 1217 * the virtual address is found (with uvm_map_findspace). the 1218 * offset is the distance we are from the start of the map. 1219 */ 1220 1221 if (uobj == NULL) { 1222 uoffset = 0; 1223 } else { 1224 if (uoffset == UVM_UNKNOWN_OFFSET) { 1225 KASSERT(UVM_OBJ_IS_KERN_OBJECT(uobj)); 1226 uoffset = start - vm_map_min(kernel_map); 1227 } 1228 } 1229 1230 args->uma_flags = flags; 1231 args->uma_prev = prev_entry; 1232 args->uma_start = start; 1233 args->uma_size = size; 1234 args->uma_uobj = uobj; 1235 args->uma_uoffset = uoffset; 1236 1237 UVMHIST_LOG(maphist, "<- done!", 0,0,0,0); 1238 return 0; 1239 } 1240 1241 /* 1242 * uvm_map_enter: 1243 * 1244 * called with map locked. 1245 * unlock the map before returning. 1246 */ 1247 1248 int 1249 uvm_map_enter(struct vm_map *map, const struct uvm_map_args *args, 1250 struct vm_map_entry *new_entry) 1251 { 1252 struct vm_map_entry *prev_entry = args->uma_prev; 1253 struct vm_map_entry *dead = NULL; 1254 1255 const uvm_flag_t flags = args->uma_flags; 1256 const vm_prot_t prot = UVM_PROTECTION(flags); 1257 const vm_prot_t maxprot = UVM_MAXPROTECTION(flags); 1258 const vm_inherit_t inherit = UVM_INHERIT(flags); 1259 const int amapwaitflag = (flags & UVM_FLAG_NOWAIT) ? 1260 AMAP_EXTEND_NOWAIT : 0; 1261 const int advice = UVM_ADVICE(flags); 1262 1263 vaddr_t start = args->uma_start; 1264 vsize_t size = args->uma_size; 1265 struct uvm_object *uobj = args->uma_uobj; 1266 voff_t uoffset = args->uma_uoffset; 1267 1268 const int kmap = (vm_map_pmap(map) == pmap_kernel()); 1269 int merged = 0; 1270 int error; 1271 int newetype; 1272 1273 UVMHIST_FUNC("uvm_map_enter"); 1274 UVMHIST_CALLED(maphist); 1275 1276 UVMHIST_LOG(maphist, "(map=%p, start=%#lx, size=%lu, flags=%#x)", 1277 map, start, size, flags); 1278 UVMHIST_LOG(maphist, " uobj/offset %p/%ld", uobj, uoffset,0,0); 1279 1280 KASSERT(map->hint == prev_entry); /* bimerge case assumes this */ 1281 KASSERT(vm_map_locked_p(map)); 1282 1283 if (uobj) 1284 newetype = UVM_ET_OBJ; 1285 else 1286 newetype = 0; 1287 1288 if (flags & UVM_FLAG_COPYONW) { 1289 newetype |= UVM_ET_COPYONWRITE; 1290 if ((flags & UVM_FLAG_OVERLAY) == 0) 1291 newetype |= UVM_ET_NEEDSCOPY; 1292 } 1293 1294 /* 1295 * try and insert in map by extending previous entry, if possible. 1296 * XXX: we don't try and pull back the next entry. might be useful 1297 * for a stack, but we are currently allocating our stack in advance. 1298 */ 1299 1300 if (flags & UVM_FLAG_NOMERGE) 1301 goto nomerge; 1302 1303 if (prev_entry->end == start && 1304 prev_entry != &map->header && 1305 UVM_ET_ISCOMPATIBLE(prev_entry, newetype, uobj, 0, 1306 prot, maxprot, inherit, advice, 0)) { 1307 1308 if (uobj && prev_entry->offset + 1309 (prev_entry->end - prev_entry->start) != uoffset) 1310 goto forwardmerge; 1311 1312 /* 1313 * can't extend a shared amap. note: no need to lock amap to 1314 * look at refs since we don't care about its exact value. 1315 * if it is one (i.e. we have only reference) it will stay there 1316 */ 1317 1318 if (prev_entry->aref.ar_amap && 1319 amap_refs(prev_entry->aref.ar_amap) != 1) { 1320 goto forwardmerge; 1321 } 1322 1323 if (prev_entry->aref.ar_amap) { 1324 error = amap_extend(prev_entry, size, 1325 amapwaitflag | AMAP_EXTEND_FORWARDS); 1326 if (error) 1327 goto nomerge; 1328 } 1329 1330 if (kmap) { 1331 UVMMAP_EVCNT_INCR(kbackmerge); 1332 } else { 1333 UVMMAP_EVCNT_INCR(ubackmerge); 1334 } 1335 UVMHIST_LOG(maphist," starting back merge", 0, 0, 0, 0); 1336 1337 /* 1338 * drop our reference to uobj since we are extending a reference 1339 * that we already have (the ref count can not drop to zero). 1340 */ 1341 1342 if (uobj && uobj->pgops->pgo_detach) 1343 uobj->pgops->pgo_detach(uobj); 1344 1345 /* 1346 * Now that we've merged the entries, note that we've grown 1347 * and our gap has shrunk. Then fix the tree. 1348 */ 1349 prev_entry->end += size; 1350 prev_entry->gap -= size; 1351 uvm_rb_fixup(map, prev_entry); 1352 1353 uvm_map_check(map, "map backmerged"); 1354 1355 UVMHIST_LOG(maphist,"<- done (via backmerge)!", 0, 0, 0, 0); 1356 merged++; 1357 } 1358 1359 forwardmerge: 1360 if (prev_entry->next->start == (start + size) && 1361 prev_entry->next != &map->header && 1362 UVM_ET_ISCOMPATIBLE(prev_entry->next, newetype, uobj, 0, 1363 prot, maxprot, inherit, advice, 0)) { 1364 1365 if (uobj && prev_entry->next->offset != uoffset + size) 1366 goto nomerge; 1367 1368 /* 1369 * can't extend a shared amap. note: no need to lock amap to 1370 * look at refs since we don't care about its exact value. 1371 * if it is one (i.e. we have only reference) it will stay there. 1372 * 1373 * note that we also can't merge two amaps, so if we 1374 * merged with the previous entry which has an amap, 1375 * and the next entry also has an amap, we give up. 1376 * 1377 * Interesting cases: 1378 * amap, new, amap -> give up second merge (single fwd extend) 1379 * amap, new, none -> double forward extend (extend again here) 1380 * none, new, amap -> double backward extend (done here) 1381 * uobj, new, amap -> single backward extend (done here) 1382 * 1383 * XXX should we attempt to deal with someone refilling 1384 * the deallocated region between two entries that are 1385 * backed by the same amap (ie, arefs is 2, "prev" and 1386 * "next" refer to it, and adding this allocation will 1387 * close the hole, thus restoring arefs to 1 and 1388 * deallocating the "next" vm_map_entry)? -- @@@ 1389 */ 1390 1391 if (prev_entry->next->aref.ar_amap && 1392 (amap_refs(prev_entry->next->aref.ar_amap) != 1 || 1393 (merged && prev_entry->aref.ar_amap))) { 1394 goto nomerge; 1395 } 1396 1397 if (merged) { 1398 /* 1399 * Try to extend the amap of the previous entry to 1400 * cover the next entry as well. If it doesn't work 1401 * just skip on, don't actually give up, since we've 1402 * already completed the back merge. 1403 */ 1404 if (prev_entry->aref.ar_amap) { 1405 if (amap_extend(prev_entry, 1406 prev_entry->next->end - 1407 prev_entry->next->start, 1408 amapwaitflag | AMAP_EXTEND_FORWARDS)) 1409 goto nomerge; 1410 } 1411 1412 /* 1413 * Try to extend the amap of the *next* entry 1414 * back to cover the new allocation *and* the 1415 * previous entry as well (the previous merge 1416 * didn't have an amap already otherwise we 1417 * wouldn't be checking here for an amap). If 1418 * it doesn't work just skip on, again, don't 1419 * actually give up, since we've already 1420 * completed the back merge. 1421 */ 1422 else if (prev_entry->next->aref.ar_amap) { 1423 if (amap_extend(prev_entry->next, 1424 prev_entry->end - 1425 prev_entry->start, 1426 amapwaitflag | AMAP_EXTEND_BACKWARDS)) 1427 goto nomerge; 1428 } 1429 } else { 1430 /* 1431 * Pull the next entry's amap backwards to cover this 1432 * new allocation. 1433 */ 1434 if (prev_entry->next->aref.ar_amap) { 1435 error = amap_extend(prev_entry->next, size, 1436 amapwaitflag | AMAP_EXTEND_BACKWARDS); 1437 if (error) 1438 goto nomerge; 1439 } 1440 } 1441 1442 if (merged) { 1443 if (kmap) { 1444 UVMMAP_EVCNT_DECR(kbackmerge); 1445 UVMMAP_EVCNT_INCR(kbimerge); 1446 } else { 1447 UVMMAP_EVCNT_DECR(ubackmerge); 1448 UVMMAP_EVCNT_INCR(ubimerge); 1449 } 1450 } else { 1451 if (kmap) { 1452 UVMMAP_EVCNT_INCR(kforwmerge); 1453 } else { 1454 UVMMAP_EVCNT_INCR(uforwmerge); 1455 } 1456 } 1457 UVMHIST_LOG(maphist," starting forward merge", 0, 0, 0, 0); 1458 1459 /* 1460 * drop our reference to uobj since we are extending a reference 1461 * that we already have (the ref count can not drop to zero). 1462 */ 1463 if (uobj && uobj->pgops->pgo_detach) 1464 uobj->pgops->pgo_detach(uobj); 1465 1466 if (merged) { 1467 dead = prev_entry->next; 1468 prev_entry->end = dead->end; 1469 uvm_map_entry_unlink(map, dead); 1470 if (dead->aref.ar_amap != NULL) { 1471 prev_entry->aref = dead->aref; 1472 dead->aref.ar_amap = NULL; 1473 } 1474 } else { 1475 prev_entry->next->start -= size; 1476 if (prev_entry != &map->header) { 1477 prev_entry->gap -= size; 1478 KASSERT(prev_entry->gap == uvm_rb_gap(prev_entry)); 1479 uvm_rb_fixup(map, prev_entry); 1480 } 1481 if (uobj) 1482 prev_entry->next->offset = uoffset; 1483 } 1484 1485 uvm_map_check(map, "map forwardmerged"); 1486 1487 UVMHIST_LOG(maphist,"<- done forwardmerge", 0, 0, 0, 0); 1488 merged++; 1489 } 1490 1491 nomerge: 1492 if (!merged) { 1493 UVMHIST_LOG(maphist," allocating new map entry", 0, 0, 0, 0); 1494 if (kmap) { 1495 UVMMAP_EVCNT_INCR(knomerge); 1496 } else { 1497 UVMMAP_EVCNT_INCR(unomerge); 1498 } 1499 1500 /* 1501 * allocate new entry and link it in. 1502 */ 1503 1504 if (new_entry == NULL) { 1505 new_entry = uvm_mapent_alloc(map, 1506 (flags & UVM_FLAG_NOWAIT)); 1507 if (__predict_false(new_entry == NULL)) { 1508 error = ENOMEM; 1509 goto done; 1510 } 1511 } 1512 new_entry->start = start; 1513 new_entry->end = new_entry->start + size; 1514 new_entry->object.uvm_obj = uobj; 1515 new_entry->offset = uoffset; 1516 1517 new_entry->etype = newetype; 1518 1519 if (flags & UVM_FLAG_NOMERGE) { 1520 new_entry->flags |= UVM_MAP_NOMERGE; 1521 } 1522 1523 new_entry->protection = prot; 1524 new_entry->max_protection = maxprot; 1525 new_entry->inheritance = inherit; 1526 new_entry->wired_count = 0; 1527 new_entry->advice = advice; 1528 if (flags & UVM_FLAG_OVERLAY) { 1529 1530 /* 1531 * to_add: for BSS we overallocate a little since we 1532 * are likely to extend 1533 */ 1534 1535 vaddr_t to_add = (flags & UVM_FLAG_AMAPPAD) ? 1536 UVM_AMAP_CHUNK << PAGE_SHIFT : 0; 1537 struct vm_amap *amap = amap_alloc(size, to_add, 1538 (flags & UVM_FLAG_NOWAIT)); 1539 if (__predict_false(amap == NULL)) { 1540 error = ENOMEM; 1541 goto done; 1542 } 1543 new_entry->aref.ar_pageoff = 0; 1544 new_entry->aref.ar_amap = amap; 1545 } else { 1546 new_entry->aref.ar_pageoff = 0; 1547 new_entry->aref.ar_amap = NULL; 1548 } 1549 uvm_map_entry_link(map, prev_entry, new_entry); 1550 1551 /* 1552 * Update the free space hint 1553 */ 1554 1555 if ((map->first_free == prev_entry) && 1556 (prev_entry->end >= new_entry->start)) 1557 map->first_free = new_entry; 1558 1559 new_entry = NULL; 1560 } 1561 1562 map->size += size; 1563 1564 UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0); 1565 1566 error = 0; 1567 done: 1568 vm_map_unlock(map); 1569 1570 if (new_entry) { 1571 uvm_mapent_free(new_entry); 1572 } 1573 1574 if (dead) { 1575 KDASSERT(merged); 1576 uvm_mapent_free(dead); 1577 } 1578 1579 return error; 1580 } 1581 1582 /* 1583 * uvm_map_lookup_entry_bytree: lookup an entry in tree 1584 */ 1585 1586 static inline bool 1587 uvm_map_lookup_entry_bytree(struct vm_map *map, vaddr_t address, 1588 struct vm_map_entry **entry /* OUT */) 1589 { 1590 struct vm_map_entry *prev = &map->header; 1591 struct vm_map_entry *cur = ROOT_ENTRY(map); 1592 1593 while (cur) { 1594 UVMMAP_EVCNT_INCR(mlk_treeloop); 1595 if (address >= cur->start) { 1596 if (address < cur->end) { 1597 *entry = cur; 1598 return true; 1599 } 1600 prev = cur; 1601 cur = RIGHT_ENTRY(cur); 1602 } else 1603 cur = LEFT_ENTRY(cur); 1604 } 1605 *entry = prev; 1606 return false; 1607 } 1608 1609 /* 1610 * uvm_map_lookup_entry: find map entry at or before an address 1611 * 1612 * => map must at least be read-locked by caller 1613 * => entry is returned in "entry" 1614 * => return value is true if address is in the returned entry 1615 */ 1616 1617 bool 1618 uvm_map_lookup_entry(struct vm_map *map, vaddr_t address, 1619 struct vm_map_entry **entry /* OUT */) 1620 { 1621 struct vm_map_entry *cur; 1622 bool use_tree = false; 1623 UVMHIST_FUNC("uvm_map_lookup_entry"); 1624 UVMHIST_CALLED(maphist); 1625 1626 UVMHIST_LOG(maphist,"(map=%p,addr=%#lx,ent=%p)", 1627 map, address, entry, 0); 1628 1629 /* 1630 * start looking either from the head of the 1631 * list, or from the hint. 1632 */ 1633 1634 cur = map->hint; 1635 1636 if (cur == &map->header) 1637 cur = cur->next; 1638 1639 UVMMAP_EVCNT_INCR(mlk_call); 1640 if (address >= cur->start) { 1641 1642 /* 1643 * go from hint to end of list. 1644 * 1645 * but first, make a quick check to see if 1646 * we are already looking at the entry we 1647 * want (which is usually the case). 1648 * note also that we don't need to save the hint 1649 * here... it is the same hint (unless we are 1650 * at the header, in which case the hint didn't 1651 * buy us anything anyway). 1652 */ 1653 1654 if (cur != &map->header && cur->end > address) { 1655 UVMMAP_EVCNT_INCR(mlk_hint); 1656 *entry = cur; 1657 UVMHIST_LOG(maphist,"<- got it via hint (%p)", 1658 cur, 0, 0, 0); 1659 uvm_mapent_check(*entry); 1660 return (true); 1661 } 1662 1663 if (map->nentries > 15) 1664 use_tree = true; 1665 } else { 1666 1667 /* 1668 * invalid hint. use tree. 1669 */ 1670 use_tree = true; 1671 } 1672 1673 uvm_map_check(map, __func__); 1674 1675 if (use_tree) { 1676 /* 1677 * Simple lookup in the tree. Happens when the hint is 1678 * invalid, or nentries reach a threshold. 1679 */ 1680 UVMMAP_EVCNT_INCR(mlk_tree); 1681 if (uvm_map_lookup_entry_bytree(map, address, entry)) { 1682 goto got; 1683 } else { 1684 goto failed; 1685 } 1686 } 1687 1688 /* 1689 * search linearly 1690 */ 1691 1692 UVMMAP_EVCNT_INCR(mlk_list); 1693 while (cur != &map->header) { 1694 UVMMAP_EVCNT_INCR(mlk_listloop); 1695 if (cur->end > address) { 1696 if (address >= cur->start) { 1697 /* 1698 * save this lookup for future 1699 * hints, and return 1700 */ 1701 1702 *entry = cur; 1703 got: 1704 SAVE_HINT(map, map->hint, *entry); 1705 UVMHIST_LOG(maphist,"<- search got it (%p)", 1706 cur, 0, 0, 0); 1707 KDASSERT((*entry)->start <= address); 1708 KDASSERT(address < (*entry)->end); 1709 uvm_mapent_check(*entry); 1710 return (true); 1711 } 1712 break; 1713 } 1714 cur = cur->next; 1715 } 1716 *entry = cur->prev; 1717 failed: 1718 SAVE_HINT(map, map->hint, *entry); 1719 UVMHIST_LOG(maphist,"<- failed!",0,0,0,0); 1720 KDASSERT((*entry) == &map->header || (*entry)->end <= address); 1721 KDASSERT((*entry)->next == &map->header || 1722 address < (*entry)->next->start); 1723 return (false); 1724 } 1725 1726 /* 1727 * See if the range between start and start + length fits in the gap 1728 * entry->next->start and entry->end. Returns 1 if fits, 0 if doesn't 1729 * fit, and -1 address wraps around. 1730 */ 1731 static int 1732 uvm_map_space_avail(vaddr_t *start, vsize_t length, voff_t uoffset, 1733 vsize_t align, int flags, int topdown, struct vm_map_entry *entry) 1734 { 1735 vaddr_t end; 1736 1737 #ifdef PMAP_PREFER 1738 /* 1739 * push start address forward as needed to avoid VAC alias problems. 1740 * we only do this if a valid offset is specified. 1741 */ 1742 1743 if (uoffset != UVM_UNKNOWN_OFFSET) 1744 PMAP_PREFER(uoffset, start, length, topdown); 1745 #endif 1746 if ((flags & UVM_FLAG_COLORMATCH) != 0) { 1747 KASSERT(align < uvmexp.ncolors); 1748 if (uvmexp.ncolors > 1) { 1749 const u_int colormask = uvmexp.colormask; 1750 const u_int colorsize = colormask + 1; 1751 vaddr_t hint = atop(*start); 1752 const u_int color = hint & colormask; 1753 if (color != align) { 1754 hint -= color; /* adjust to color boundary */ 1755 KASSERT((hint & colormask) == 0); 1756 if (topdown) { 1757 if (align > color) 1758 hint -= colorsize; 1759 } else { 1760 if (align < color) 1761 hint += colorsize; 1762 } 1763 *start = ptoa(hint + align); /* adjust to color */ 1764 } 1765 } 1766 } else if (align != 0) { 1767 if ((*start & (align - 1)) != 0) { 1768 if (topdown) 1769 *start &= ~(align - 1); 1770 else 1771 *start = roundup(*start, align); 1772 } 1773 /* 1774 * XXX Should we PMAP_PREFER() here again? 1775 * eh...i think we're okay 1776 */ 1777 } 1778 1779 /* 1780 * Find the end of the proposed new region. Be sure we didn't 1781 * wrap around the address; if so, we lose. Otherwise, if the 1782 * proposed new region fits before the next entry, we win. 1783 */ 1784 1785 end = *start + length; 1786 if (end < *start) 1787 return (-1); 1788 1789 if (entry->next->start >= end && *start >= entry->end) 1790 return (1); 1791 1792 return (0); 1793 } 1794 1795 /* 1796 * uvm_map_findspace: find "length" sized space in "map". 1797 * 1798 * => "hint" is a hint about where we want it, unless UVM_FLAG_FIXED is 1799 * set in "flags" (in which case we insist on using "hint"). 1800 * => "result" is VA returned 1801 * => uobj/uoffset are to be used to handle VAC alignment, if required 1802 * => if "align" is non-zero, we attempt to align to that value. 1803 * => caller must at least have read-locked map 1804 * => returns NULL on failure, or pointer to prev. map entry if success 1805 * => note this is a cross between the old vm_map_findspace and vm_map_find 1806 */ 1807 1808 struct vm_map_entry * 1809 uvm_map_findspace(struct vm_map *map, vaddr_t hint, vsize_t length, 1810 vaddr_t *result /* OUT */, struct uvm_object *uobj, voff_t uoffset, 1811 vsize_t align, int flags) 1812 { 1813 struct vm_map_entry *entry; 1814 struct vm_map_entry *child, *prev, *tmp; 1815 vaddr_t orig_hint __diagused; 1816 const int topdown = map->flags & VM_MAP_TOPDOWN; 1817 UVMHIST_FUNC("uvm_map_findspace"); 1818 UVMHIST_CALLED(maphist); 1819 1820 UVMHIST_LOG(maphist, "(map=%p, hint=%l#x, len=%lu, flags=%#x)", 1821 map, hint, length, flags); 1822 KASSERT((flags & UVM_FLAG_COLORMATCH) != 0 || (align & (align - 1)) == 0); 1823 KASSERT((flags & UVM_FLAG_COLORMATCH) == 0 || align < uvmexp.ncolors); 1824 KASSERT((flags & UVM_FLAG_FIXED) == 0 || align == 0); 1825 1826 uvm_map_check(map, "map_findspace entry"); 1827 1828 /* 1829 * remember the original hint. if we are aligning, then we 1830 * may have to try again with no alignment constraint if 1831 * we fail the first time. 1832 */ 1833 1834 orig_hint = hint; 1835 if (hint < vm_map_min(map)) { /* check ranges ... */ 1836 if (flags & UVM_FLAG_FIXED) { 1837 UVMHIST_LOG(maphist,"<- VA below map range",0,0,0,0); 1838 return (NULL); 1839 } 1840 hint = vm_map_min(map); 1841 } 1842 if (hint > vm_map_max(map)) { 1843 UVMHIST_LOG(maphist,"<- VA %#lx > range [%#lx->%#lx]", 1844 hint, vm_map_min(map), vm_map_max(map), 0); 1845 return (NULL); 1846 } 1847 1848 /* 1849 * Look for the first possible address; if there's already 1850 * something at this address, we have to start after it. 1851 */ 1852 1853 /* 1854 * @@@: there are four, no, eight cases to consider. 1855 * 1856 * 0: found, fixed, bottom up -> fail 1857 * 1: found, fixed, top down -> fail 1858 * 2: found, not fixed, bottom up -> start after entry->end, 1859 * loop up 1860 * 3: found, not fixed, top down -> start before entry->start, 1861 * loop down 1862 * 4: not found, fixed, bottom up -> check entry->next->start, fail 1863 * 5: not found, fixed, top down -> check entry->next->start, fail 1864 * 6: not found, not fixed, bottom up -> check entry->next->start, 1865 * loop up 1866 * 7: not found, not fixed, top down -> check entry->next->start, 1867 * loop down 1868 * 1869 * as you can see, it reduces to roughly five cases, and that 1870 * adding top down mapping only adds one unique case (without 1871 * it, there would be four cases). 1872 */ 1873 1874 if ((flags & UVM_FLAG_FIXED) == 0 && hint == vm_map_min(map)) { 1875 entry = map->first_free; 1876 } else { 1877 if (uvm_map_lookup_entry(map, hint, &entry)) { 1878 /* "hint" address already in use ... */ 1879 if (flags & UVM_FLAG_FIXED) { 1880 UVMHIST_LOG(maphist, "<- fixed & VA in use", 1881 0, 0, 0, 0); 1882 return (NULL); 1883 } 1884 if (topdown) 1885 /* Start from lower gap. */ 1886 entry = entry->prev; 1887 } else if (flags & UVM_FLAG_FIXED) { 1888 if (entry->next->start >= hint + length && 1889 hint + length > hint) 1890 goto found; 1891 1892 /* "hint" address is gap but too small */ 1893 UVMHIST_LOG(maphist, "<- fixed mapping failed", 1894 0, 0, 0, 0); 1895 return (NULL); /* only one shot at it ... */ 1896 } else { 1897 /* 1898 * See if given hint fits in this gap. 1899 */ 1900 switch (uvm_map_space_avail(&hint, length, 1901 uoffset, align, flags, topdown, entry)) { 1902 case 1: 1903 goto found; 1904 case -1: 1905 goto wraparound; 1906 } 1907 1908 if (topdown) { 1909 /* 1910 * Still there is a chance to fit 1911 * if hint > entry->end. 1912 */ 1913 } else { 1914 /* Start from higher gap. */ 1915 entry = entry->next; 1916 if (entry == &map->header) 1917 goto notfound; 1918 goto nextgap; 1919 } 1920 } 1921 } 1922 1923 /* 1924 * Note that all UVM_FLAGS_FIXED case is already handled. 1925 */ 1926 KDASSERT((flags & UVM_FLAG_FIXED) == 0); 1927 1928 /* Try to find the space in the red-black tree */ 1929 1930 /* Check slot before any entry */ 1931 hint = topdown ? entry->next->start - length : entry->end; 1932 switch (uvm_map_space_avail(&hint, length, uoffset, align, flags, 1933 topdown, entry)) { 1934 case 1: 1935 goto found; 1936 case -1: 1937 goto wraparound; 1938 } 1939 1940 nextgap: 1941 KDASSERT((flags & UVM_FLAG_FIXED) == 0); 1942 /* If there is not enough space in the whole tree, we fail */ 1943 tmp = ROOT_ENTRY(map); 1944 if (tmp == NULL || tmp->maxgap < length) 1945 goto notfound; 1946 1947 prev = NULL; /* previous candidate */ 1948 1949 /* Find an entry close to hint that has enough space */ 1950 for (; tmp;) { 1951 KASSERT(tmp->next->start == tmp->end + tmp->gap); 1952 if (topdown) { 1953 if (tmp->next->start < hint + length && 1954 (prev == NULL || tmp->end > prev->end)) { 1955 if (tmp->gap >= length) 1956 prev = tmp; 1957 else if ((child = LEFT_ENTRY(tmp)) != NULL 1958 && child->maxgap >= length) 1959 prev = tmp; 1960 } 1961 } else { 1962 if (tmp->end >= hint && 1963 (prev == NULL || tmp->end < prev->end)) { 1964 if (tmp->gap >= length) 1965 prev = tmp; 1966 else if ((child = RIGHT_ENTRY(tmp)) != NULL 1967 && child->maxgap >= length) 1968 prev = tmp; 1969 } 1970 } 1971 if (tmp->next->start < hint + length) 1972 child = RIGHT_ENTRY(tmp); 1973 else if (tmp->end > hint) 1974 child = LEFT_ENTRY(tmp); 1975 else { 1976 if (tmp->gap >= length) 1977 break; 1978 if (topdown) 1979 child = LEFT_ENTRY(tmp); 1980 else 1981 child = RIGHT_ENTRY(tmp); 1982 } 1983 if (child == NULL || child->maxgap < length) 1984 break; 1985 tmp = child; 1986 } 1987 1988 if (tmp != NULL && tmp->start < hint && hint < tmp->next->start) { 1989 /* 1990 * Check if the entry that we found satifies the 1991 * space requirement 1992 */ 1993 if (topdown) { 1994 if (hint > tmp->next->start - length) 1995 hint = tmp->next->start - length; 1996 } else { 1997 if (hint < tmp->end) 1998 hint = tmp->end; 1999 } 2000 switch (uvm_map_space_avail(&hint, length, uoffset, align, 2001 flags, topdown, tmp)) { 2002 case 1: 2003 entry = tmp; 2004 goto found; 2005 case -1: 2006 goto wraparound; 2007 } 2008 if (tmp->gap >= length) 2009 goto listsearch; 2010 } 2011 if (prev == NULL) 2012 goto notfound; 2013 2014 if (topdown) { 2015 KASSERT(orig_hint >= prev->next->start - length || 2016 prev->next->start - length > prev->next->start); 2017 hint = prev->next->start - length; 2018 } else { 2019 KASSERT(orig_hint <= prev->end); 2020 hint = prev->end; 2021 } 2022 switch (uvm_map_space_avail(&hint, length, uoffset, align, 2023 flags, topdown, prev)) { 2024 case 1: 2025 entry = prev; 2026 goto found; 2027 case -1: 2028 goto wraparound; 2029 } 2030 if (prev->gap >= length) 2031 goto listsearch; 2032 2033 if (topdown) 2034 tmp = LEFT_ENTRY(prev); 2035 else 2036 tmp = RIGHT_ENTRY(prev); 2037 for (;;) { 2038 KASSERT(tmp && tmp->maxgap >= length); 2039 if (topdown) 2040 child = RIGHT_ENTRY(tmp); 2041 else 2042 child = LEFT_ENTRY(tmp); 2043 if (child && child->maxgap >= length) { 2044 tmp = child; 2045 continue; 2046 } 2047 if (tmp->gap >= length) 2048 break; 2049 if (topdown) 2050 tmp = LEFT_ENTRY(tmp); 2051 else 2052 tmp = RIGHT_ENTRY(tmp); 2053 } 2054 2055 if (topdown) { 2056 KASSERT(orig_hint >= tmp->next->start - length || 2057 tmp->next->start - length > tmp->next->start); 2058 hint = tmp->next->start - length; 2059 } else { 2060 KASSERT(orig_hint <= tmp->end); 2061 hint = tmp->end; 2062 } 2063 switch (uvm_map_space_avail(&hint, length, uoffset, align, 2064 flags, topdown, tmp)) { 2065 case 1: 2066 entry = tmp; 2067 goto found; 2068 case -1: 2069 goto wraparound; 2070 } 2071 2072 /* 2073 * The tree fails to find an entry because of offset or alignment 2074 * restrictions. Search the list instead. 2075 */ 2076 listsearch: 2077 /* 2078 * Look through the rest of the map, trying to fit a new region in 2079 * the gap between existing regions, or after the very last region. 2080 * note: entry->end = base VA of current gap, 2081 * entry->next->start = VA of end of current gap 2082 */ 2083 2084 for (;;) { 2085 /* Update hint for current gap. */ 2086 hint = topdown ? entry->next->start - length : entry->end; 2087 2088 /* See if it fits. */ 2089 switch (uvm_map_space_avail(&hint, length, uoffset, align, 2090 flags, topdown, entry)) { 2091 case 1: 2092 goto found; 2093 case -1: 2094 goto wraparound; 2095 } 2096 2097 /* Advance to next/previous gap */ 2098 if (topdown) { 2099 if (entry == &map->header) { 2100 UVMHIST_LOG(maphist, "<- failed (off start)", 2101 0,0,0,0); 2102 goto notfound; 2103 } 2104 entry = entry->prev; 2105 } else { 2106 entry = entry->next; 2107 if (entry == &map->header) { 2108 UVMHIST_LOG(maphist, "<- failed (off end)", 2109 0,0,0,0); 2110 goto notfound; 2111 } 2112 } 2113 } 2114 2115 found: 2116 SAVE_HINT(map, map->hint, entry); 2117 *result = hint; 2118 UVMHIST_LOG(maphist,"<- got it! (result=%#lx)", hint, 0,0,0); 2119 KASSERTMSG( topdown || hint >= orig_hint, "hint: %jx, orig_hint: %jx", 2120 (uintmax_t)hint, (uintmax_t)orig_hint); 2121 KASSERTMSG(!topdown || hint <= orig_hint, "hint: %jx, orig_hint: %jx", 2122 (uintmax_t)hint, (uintmax_t)orig_hint); 2123 KASSERT(entry->end <= hint); 2124 KASSERT(hint + length <= entry->next->start); 2125 return (entry); 2126 2127 wraparound: 2128 UVMHIST_LOG(maphist, "<- failed (wrap around)", 0,0,0,0); 2129 2130 return (NULL); 2131 2132 notfound: 2133 UVMHIST_LOG(maphist, "<- failed (notfound)", 0,0,0,0); 2134 2135 return (NULL); 2136 } 2137 2138 /* 2139 * U N M A P - m a i n h e l p e r f u n c t i o n s 2140 */ 2141 2142 /* 2143 * uvm_unmap_remove: remove mappings from a vm_map (from "start" up to "stop") 2144 * 2145 * => caller must check alignment and size 2146 * => map must be locked by caller 2147 * => we return a list of map entries that we've remove from the map 2148 * in "entry_list" 2149 */ 2150 2151 void 2152 uvm_unmap_remove(struct vm_map *map, vaddr_t start, vaddr_t end, 2153 struct vm_map_entry **entry_list /* OUT */, int flags) 2154 { 2155 struct vm_map_entry *entry, *first_entry, *next; 2156 vaddr_t len; 2157 UVMHIST_FUNC("uvm_unmap_remove"); UVMHIST_CALLED(maphist); 2158 2159 UVMHIST_LOG(maphist,"(map=%p, start=%#lx, end=%#lx)", 2160 map, start, end, 0); 2161 VM_MAP_RANGE_CHECK(map, start, end); 2162 2163 uvm_map_check(map, "unmap_remove entry"); 2164 2165 /* 2166 * find first entry 2167 */ 2168 2169 if (uvm_map_lookup_entry(map, start, &first_entry) == true) { 2170 /* clip and go... */ 2171 entry = first_entry; 2172 UVM_MAP_CLIP_START(map, entry, start); 2173 /* critical! prevents stale hint */ 2174 SAVE_HINT(map, entry, entry->prev); 2175 } else { 2176 entry = first_entry->next; 2177 } 2178 2179 /* 2180 * Save the free space hint 2181 */ 2182 2183 if (map->first_free != &map->header && map->first_free->start >= start) 2184 map->first_free = entry->prev; 2185 2186 /* 2187 * note: we now re-use first_entry for a different task. we remove 2188 * a number of map entries from the map and save them in a linked 2189 * list headed by "first_entry". once we remove them from the map 2190 * the caller should unlock the map and drop the references to the 2191 * backing objects [c.f. uvm_unmap_detach]. the object is to 2192 * separate unmapping from reference dropping. why? 2193 * [1] the map has to be locked for unmapping 2194 * [2] the map need not be locked for reference dropping 2195 * [3] dropping references may trigger pager I/O, and if we hit 2196 * a pager that does synchronous I/O we may have to wait for it. 2197 * [4] we would like all waiting for I/O to occur with maps unlocked 2198 * so that we don't block other threads. 2199 */ 2200 2201 first_entry = NULL; 2202 *entry_list = NULL; 2203 2204 /* 2205 * break up the area into map entry sized regions and unmap. note 2206 * that all mappings have to be removed before we can even consider 2207 * dropping references to amaps or VM objects (otherwise we could end 2208 * up with a mapping to a page on the free list which would be very bad) 2209 */ 2210 2211 while ((entry != &map->header) && (entry->start < end)) { 2212 KASSERT((entry->flags & UVM_MAP_STATIC) == 0); 2213 2214 UVM_MAP_CLIP_END(map, entry, end); 2215 next = entry->next; 2216 len = entry->end - entry->start; 2217 2218 /* 2219 * unwire before removing addresses from the pmap; otherwise 2220 * unwiring will put the entries back into the pmap (XXX). 2221 */ 2222 2223 if (VM_MAPENT_ISWIRED(entry)) { 2224 uvm_map_entry_unwire(map, entry); 2225 } 2226 if (flags & UVM_FLAG_VAONLY) { 2227 2228 /* nothing */ 2229 2230 } else if ((map->flags & VM_MAP_PAGEABLE) == 0) { 2231 2232 /* 2233 * if the map is non-pageable, any pages mapped there 2234 * must be wired and entered with pmap_kenter_pa(), 2235 * and we should free any such pages immediately. 2236 * this is mostly used for kmem_map. 2237 */ 2238 KASSERT(vm_map_pmap(map) == pmap_kernel()); 2239 2240 uvm_km_pgremove_intrsafe(map, entry->start, entry->end); 2241 } else if (UVM_ET_ISOBJ(entry) && 2242 UVM_OBJ_IS_KERN_OBJECT(entry->object.uvm_obj)) { 2243 panic("%s: kernel object %p %p\n", 2244 __func__, map, entry); 2245 } else if (UVM_ET_ISOBJ(entry) || entry->aref.ar_amap) { 2246 /* 2247 * remove mappings the standard way. lock object 2248 * and/or amap to ensure vm_page state does not 2249 * change while in pmap_remove(). 2250 */ 2251 2252 uvm_map_lock_entry(entry); 2253 pmap_remove(map->pmap, entry->start, entry->end); 2254 uvm_map_unlock_entry(entry); 2255 } 2256 2257 #if defined(UVMDEBUG) 2258 /* 2259 * check if there's remaining mapping, 2260 * which is a bug in caller. 2261 */ 2262 2263 vaddr_t va; 2264 for (va = entry->start; va < entry->end; 2265 va += PAGE_SIZE) { 2266 if (pmap_extract(vm_map_pmap(map), va, NULL)) { 2267 panic("%s: %#"PRIxVADDR" has mapping", 2268 __func__, va); 2269 } 2270 } 2271 2272 if (VM_MAP_IS_KERNEL(map) && (flags & UVM_FLAG_NOWAIT) == 0) { 2273 uvm_km_check_empty(map, entry->start, 2274 entry->end); 2275 } 2276 #endif /* defined(UVMDEBUG) */ 2277 2278 /* 2279 * remove entry from map and put it on our list of entries 2280 * that we've nuked. then go to next entry. 2281 */ 2282 2283 UVMHIST_LOG(maphist, " removed map entry %p", entry, 0, 0,0); 2284 2285 /* critical! prevents stale hint */ 2286 SAVE_HINT(map, entry, entry->prev); 2287 2288 uvm_map_entry_unlink(map, entry); 2289 KASSERT(map->size >= len); 2290 map->size -= len; 2291 entry->prev = NULL; 2292 entry->next = first_entry; 2293 first_entry = entry; 2294 entry = next; 2295 } 2296 2297 /* 2298 * Note: if map is dying, leave pmap_update() for pmap_destroy(), 2299 * which will be called later. 2300 */ 2301 if ((map->flags & VM_MAP_DYING) == 0) { 2302 pmap_update(vm_map_pmap(map)); 2303 } else { 2304 KASSERT(vm_map_pmap(map) != pmap_kernel()); 2305 } 2306 2307 uvm_map_check(map, "unmap_remove leave"); 2308 2309 /* 2310 * now we've cleaned up the map and are ready for the caller to drop 2311 * references to the mapped objects. 2312 */ 2313 2314 *entry_list = first_entry; 2315 UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0); 2316 2317 if (map->flags & VM_MAP_WANTVA) { 2318 mutex_enter(&map->misc_lock); 2319 map->flags &= ~VM_MAP_WANTVA; 2320 cv_broadcast(&map->cv); 2321 mutex_exit(&map->misc_lock); 2322 } 2323 } 2324 2325 /* 2326 * uvm_unmap_detach: drop references in a chain of map entries 2327 * 2328 * => we will free the map entries as we traverse the list. 2329 */ 2330 2331 void 2332 uvm_unmap_detach(struct vm_map_entry *first_entry, int flags) 2333 { 2334 struct vm_map_entry *next_entry; 2335 UVMHIST_FUNC("uvm_unmap_detach"); UVMHIST_CALLED(maphist); 2336 2337 while (first_entry) { 2338 KASSERT(!VM_MAPENT_ISWIRED(first_entry)); 2339 UVMHIST_LOG(maphist, 2340 " detach %p: amap=%p, obj=%p, submap?=%d", 2341 first_entry, first_entry->aref.ar_amap, 2342 first_entry->object.uvm_obj, 2343 UVM_ET_ISSUBMAP(first_entry)); 2344 2345 /* 2346 * drop reference to amap, if we've got one 2347 */ 2348 2349 if (first_entry->aref.ar_amap) 2350 uvm_map_unreference_amap(first_entry, flags); 2351 2352 /* 2353 * drop reference to our backing object, if we've got one 2354 */ 2355 2356 KASSERT(!UVM_ET_ISSUBMAP(first_entry)); 2357 if (UVM_ET_ISOBJ(first_entry) && 2358 first_entry->object.uvm_obj->pgops->pgo_detach) { 2359 (*first_entry->object.uvm_obj->pgops->pgo_detach) 2360 (first_entry->object.uvm_obj); 2361 } 2362 next_entry = first_entry->next; 2363 uvm_mapent_free(first_entry); 2364 first_entry = next_entry; 2365 } 2366 UVMHIST_LOG(maphist, "<- done", 0,0,0,0); 2367 } 2368 2369 /* 2370 * E X T R A C T I O N F U N C T I O N S 2371 */ 2372 2373 /* 2374 * uvm_map_reserve: reserve space in a vm_map for future use. 2375 * 2376 * => we reserve space in a map by putting a dummy map entry in the 2377 * map (dummy means obj=NULL, amap=NULL, prot=VM_PROT_NONE) 2378 * => map should be unlocked (we will write lock it) 2379 * => we return true if we were able to reserve space 2380 * => XXXCDC: should be inline? 2381 */ 2382 2383 int 2384 uvm_map_reserve(struct vm_map *map, vsize_t size, 2385 vaddr_t offset /* hint for pmap_prefer */, 2386 vsize_t align /* alignment */, 2387 vaddr_t *raddr /* IN:hint, OUT: reserved VA */, 2388 uvm_flag_t flags /* UVM_FLAG_FIXED or UVM_FLAG_COLORMATCH or 0 */) 2389 { 2390 UVMHIST_FUNC("uvm_map_reserve"); UVMHIST_CALLED(maphist); 2391 2392 UVMHIST_LOG(maphist, "(map=%p, size=%#lx, offset=%#lx, addr=%p)", 2393 map,size,offset,raddr); 2394 2395 size = round_page(size); 2396 2397 /* 2398 * reserve some virtual space. 2399 */ 2400 2401 if (uvm_map(map, raddr, size, NULL, offset, align, 2402 UVM_MAPFLAG(UVM_PROT_NONE, UVM_PROT_NONE, UVM_INH_NONE, 2403 UVM_ADV_RANDOM, UVM_FLAG_NOMERGE|flags)) != 0) { 2404 UVMHIST_LOG(maphist, "<- done (no VM)", 0,0,0,0); 2405 return (false); 2406 } 2407 2408 UVMHIST_LOG(maphist, "<- done (*raddr=%#lx)", *raddr,0,0,0); 2409 return (true); 2410 } 2411 2412 /* 2413 * uvm_map_replace: replace a reserved (blank) area of memory with 2414 * real mappings. 2415 * 2416 * => caller must WRITE-LOCK the map 2417 * => we return true if replacement was a success 2418 * => we expect the newents chain to have nnewents entrys on it and 2419 * we expect newents->prev to point to the last entry on the list 2420 * => note newents is allowed to be NULL 2421 */ 2422 2423 static int 2424 uvm_map_replace(struct vm_map *map, vaddr_t start, vaddr_t end, 2425 struct vm_map_entry *newents, int nnewents, vsize_t nsize, 2426 struct vm_map_entry **oldentryp) 2427 { 2428 struct vm_map_entry *oldent, *last; 2429 2430 uvm_map_check(map, "map_replace entry"); 2431 2432 /* 2433 * first find the blank map entry at the specified address 2434 */ 2435 2436 if (!uvm_map_lookup_entry(map, start, &oldent)) { 2437 return (false); 2438 } 2439 2440 /* 2441 * check to make sure we have a proper blank entry 2442 */ 2443 2444 if (end < oldent->end) { 2445 UVM_MAP_CLIP_END(map, oldent, end); 2446 } 2447 if (oldent->start != start || oldent->end != end || 2448 oldent->object.uvm_obj != NULL || oldent->aref.ar_amap != NULL) { 2449 return (false); 2450 } 2451 2452 #ifdef DIAGNOSTIC 2453 2454 /* 2455 * sanity check the newents chain 2456 */ 2457 2458 { 2459 struct vm_map_entry *tmpent = newents; 2460 int nent = 0; 2461 vsize_t sz = 0; 2462 vaddr_t cur = start; 2463 2464 while (tmpent) { 2465 nent++; 2466 sz += tmpent->end - tmpent->start; 2467 if (tmpent->start < cur) 2468 panic("uvm_map_replace1"); 2469 if (tmpent->start >= tmpent->end || tmpent->end > end) { 2470 panic("uvm_map_replace2: " 2471 "tmpent->start=%#"PRIxVADDR 2472 ", tmpent->end=%#"PRIxVADDR 2473 ", end=%#"PRIxVADDR, 2474 tmpent->start, tmpent->end, end); 2475 } 2476 cur = tmpent->end; 2477 if (tmpent->next) { 2478 if (tmpent->next->prev != tmpent) 2479 panic("uvm_map_replace3"); 2480 } else { 2481 if (newents->prev != tmpent) 2482 panic("uvm_map_replace4"); 2483 } 2484 tmpent = tmpent->next; 2485 } 2486 if (nent != nnewents) 2487 panic("uvm_map_replace5"); 2488 if (sz != nsize) 2489 panic("uvm_map_replace6"); 2490 } 2491 #endif 2492 2493 /* 2494 * map entry is a valid blank! replace it. (this does all the 2495 * work of map entry link/unlink...). 2496 */ 2497 2498 if (newents) { 2499 last = newents->prev; 2500 2501 /* critical: flush stale hints out of map */ 2502 SAVE_HINT(map, map->hint, newents); 2503 if (map->first_free == oldent) 2504 map->first_free = last; 2505 2506 last->next = oldent->next; 2507 last->next->prev = last; 2508 2509 /* Fix RB tree */ 2510 uvm_rb_remove(map, oldent); 2511 2512 newents->prev = oldent->prev; 2513 newents->prev->next = newents; 2514 map->nentries = map->nentries + (nnewents - 1); 2515 2516 /* Fixup the RB tree */ 2517 { 2518 int i; 2519 struct vm_map_entry *tmp; 2520 2521 tmp = newents; 2522 for (i = 0; i < nnewents && tmp; i++) { 2523 uvm_rb_insert(map, tmp); 2524 tmp = tmp->next; 2525 } 2526 } 2527 } else { 2528 /* NULL list of new entries: just remove the old one */ 2529 clear_hints(map, oldent); 2530 uvm_map_entry_unlink(map, oldent); 2531 } 2532 map->size -= end - start - nsize; 2533 2534 uvm_map_check(map, "map_replace leave"); 2535 2536 /* 2537 * now we can free the old blank entry and return. 2538 */ 2539 2540 *oldentryp = oldent; 2541 return (true); 2542 } 2543 2544 /* 2545 * uvm_map_extract: extract a mapping from a map and put it somewhere 2546 * (maybe removing the old mapping) 2547 * 2548 * => maps should be unlocked (we will write lock them) 2549 * => returns 0 on success, error code otherwise 2550 * => start must be page aligned 2551 * => len must be page sized 2552 * => flags: 2553 * UVM_EXTRACT_REMOVE: remove mappings from srcmap 2554 * UVM_EXTRACT_CONTIG: abort if unmapped area (advisory only) 2555 * UVM_EXTRACT_QREF: for a temporary extraction do quick obj refs 2556 * UVM_EXTRACT_FIXPROT: set prot to maxprot as we go 2557 * UVM_EXTRACT_PROT_ALL: set prot to UVM_PROT_ALL as we go 2558 * >>>NOTE: if you set REMOVE, you are not allowed to use CONTIG or QREF!<<< 2559 * >>>NOTE: QREF's must be unmapped via the QREF path, thus should only 2560 * be used from within the kernel in a kernel level map <<< 2561 */ 2562 2563 int 2564 uvm_map_extract(struct vm_map *srcmap, vaddr_t start, vsize_t len, 2565 struct vm_map *dstmap, vaddr_t *dstaddrp, int flags) 2566 { 2567 vaddr_t dstaddr, end, newend, oldoffset, fudge, orig_fudge; 2568 struct vm_map_entry *chain, *endchain, *entry, *orig_entry, *newentry, 2569 *deadentry, *oldentry; 2570 struct vm_map_entry *resentry = NULL; /* a dummy reservation entry */ 2571 vsize_t elen __unused; 2572 int nchain, error, copy_ok; 2573 vsize_t nsize; 2574 UVMHIST_FUNC("uvm_map_extract"); UVMHIST_CALLED(maphist); 2575 2576 UVMHIST_LOG(maphist,"(srcmap=%p,start=%#lx, len=%#lx", srcmap, start, 2577 len,0); 2578 UVMHIST_LOG(maphist," ...,dstmap=%p, flags=%#x)", dstmap,flags,0,0); 2579 2580 /* 2581 * step 0: sanity check: start must be on a page boundary, length 2582 * must be page sized. can't ask for CONTIG/QREF if you asked for 2583 * REMOVE. 2584 */ 2585 2586 KASSERT((start & PAGE_MASK) == 0 && (len & PAGE_MASK) == 0); 2587 KASSERT((flags & UVM_EXTRACT_REMOVE) == 0 || 2588 (flags & (UVM_EXTRACT_CONTIG|UVM_EXTRACT_QREF)) == 0); 2589 2590 /* 2591 * step 1: reserve space in the target map for the extracted area 2592 */ 2593 2594 if ((flags & UVM_EXTRACT_RESERVED) == 0) { 2595 dstaddr = vm_map_min(dstmap); 2596 if (!uvm_map_reserve(dstmap, len, start, 2597 atop(start) & uvmexp.colormask, &dstaddr, 2598 UVM_FLAG_COLORMATCH)) 2599 return (ENOMEM); 2600 KASSERT((atop(start ^ dstaddr) & uvmexp.colormask) == 0); 2601 *dstaddrp = dstaddr; /* pass address back to caller */ 2602 UVMHIST_LOG(maphist, " dstaddr=%#lx", dstaddr,0,0,0); 2603 } else { 2604 dstaddr = *dstaddrp; 2605 } 2606 2607 /* 2608 * step 2: setup for the extraction process loop by init'ing the 2609 * map entry chain, locking src map, and looking up the first useful 2610 * entry in the map. 2611 */ 2612 2613 end = start + len; 2614 newend = dstaddr + len; 2615 chain = endchain = NULL; 2616 nchain = 0; 2617 nsize = 0; 2618 vm_map_lock(srcmap); 2619 2620 if (uvm_map_lookup_entry(srcmap, start, &entry)) { 2621 2622 /* "start" is within an entry */ 2623 if (flags & UVM_EXTRACT_QREF) { 2624 2625 /* 2626 * for quick references we don't clip the entry, so 2627 * the entry may map space "before" the starting 2628 * virtual address... this is the "fudge" factor 2629 * (which can be non-zero only the first time 2630 * through the "while" loop in step 3). 2631 */ 2632 2633 fudge = start - entry->start; 2634 } else { 2635 2636 /* 2637 * normal reference: we clip the map to fit (thus 2638 * fudge is zero) 2639 */ 2640 2641 UVM_MAP_CLIP_START(srcmap, entry, start); 2642 SAVE_HINT(srcmap, srcmap->hint, entry->prev); 2643 fudge = 0; 2644 } 2645 } else { 2646 2647 /* "start" is not within an entry ... skip to next entry */ 2648 if (flags & UVM_EXTRACT_CONTIG) { 2649 error = EINVAL; 2650 goto bad; /* definite hole here ... */ 2651 } 2652 2653 entry = entry->next; 2654 fudge = 0; 2655 } 2656 2657 /* save values from srcmap for step 6 */ 2658 orig_entry = entry; 2659 orig_fudge = fudge; 2660 2661 /* 2662 * step 3: now start looping through the map entries, extracting 2663 * as we go. 2664 */ 2665 2666 while (entry->start < end && entry != &srcmap->header) { 2667 2668 /* if we are not doing a quick reference, clip it */ 2669 if ((flags & UVM_EXTRACT_QREF) == 0) 2670 UVM_MAP_CLIP_END(srcmap, entry, end); 2671 2672 /* clear needs_copy (allow chunking) */ 2673 if (UVM_ET_ISNEEDSCOPY(entry)) { 2674 amap_copy(srcmap, entry, 2675 AMAP_COPY_NOWAIT|AMAP_COPY_NOMERGE, start, end); 2676 if (UVM_ET_ISNEEDSCOPY(entry)) { /* failed? */ 2677 error = ENOMEM; 2678 goto bad; 2679 } 2680 2681 /* amap_copy could clip (during chunk)! update fudge */ 2682 if (fudge) { 2683 fudge = start - entry->start; 2684 orig_fudge = fudge; 2685 } 2686 } 2687 2688 /* calculate the offset of this from "start" */ 2689 oldoffset = (entry->start + fudge) - start; 2690 2691 /* allocate a new map entry */ 2692 newentry = uvm_mapent_alloc(dstmap, 0); 2693 if (newentry == NULL) { 2694 error = ENOMEM; 2695 goto bad; 2696 } 2697 2698 /* set up new map entry */ 2699 newentry->next = NULL; 2700 newentry->prev = endchain; 2701 newentry->start = dstaddr + oldoffset; 2702 newentry->end = 2703 newentry->start + (entry->end - (entry->start + fudge)); 2704 if (newentry->end > newend || newentry->end < newentry->start) 2705 newentry->end = newend; 2706 newentry->object.uvm_obj = entry->object.uvm_obj; 2707 if (newentry->object.uvm_obj) { 2708 if (newentry->object.uvm_obj->pgops->pgo_reference) 2709 newentry->object.uvm_obj->pgops-> 2710 pgo_reference(newentry->object.uvm_obj); 2711 newentry->offset = entry->offset + fudge; 2712 } else { 2713 newentry->offset = 0; 2714 } 2715 newentry->etype = entry->etype; 2716 if (flags & UVM_EXTRACT_PROT_ALL) { 2717 newentry->protection = newentry->max_protection = 2718 UVM_PROT_ALL; 2719 } else { 2720 newentry->protection = (flags & UVM_EXTRACT_FIXPROT) ? 2721 entry->max_protection : entry->protection; 2722 newentry->max_protection = entry->max_protection; 2723 } 2724 newentry->inheritance = entry->inheritance; 2725 newentry->wired_count = 0; 2726 newentry->aref.ar_amap = entry->aref.ar_amap; 2727 if (newentry->aref.ar_amap) { 2728 newentry->aref.ar_pageoff = 2729 entry->aref.ar_pageoff + (fudge >> PAGE_SHIFT); 2730 uvm_map_reference_amap(newentry, AMAP_SHARED | 2731 ((flags & UVM_EXTRACT_QREF) ? AMAP_REFALL : 0)); 2732 } else { 2733 newentry->aref.ar_pageoff = 0; 2734 } 2735 newentry->advice = entry->advice; 2736 if ((flags & UVM_EXTRACT_QREF) != 0) { 2737 newentry->flags |= UVM_MAP_NOMERGE; 2738 } 2739 2740 /* now link it on the chain */ 2741 nchain++; 2742 nsize += newentry->end - newentry->start; 2743 if (endchain == NULL) { 2744 chain = endchain = newentry; 2745 } else { 2746 endchain->next = newentry; 2747 endchain = newentry; 2748 } 2749 2750 /* end of 'while' loop! */ 2751 if ((flags & UVM_EXTRACT_CONTIG) && entry->end < end && 2752 (entry->next == &srcmap->header || 2753 entry->next->start != entry->end)) { 2754 error = EINVAL; 2755 goto bad; 2756 } 2757 entry = entry->next; 2758 fudge = 0; 2759 } 2760 2761 /* 2762 * step 4: close off chain (in format expected by uvm_map_replace) 2763 */ 2764 2765 if (chain) 2766 chain->prev = endchain; 2767 2768 /* 2769 * step 5: attempt to lock the dest map so we can pmap_copy. 2770 * note usage of copy_ok: 2771 * 1 => dstmap locked, pmap_copy ok, and we "replace" here (step 5) 2772 * 0 => dstmap unlocked, NO pmap_copy, and we will "replace" in step 7 2773 */ 2774 2775 if (srcmap == dstmap || vm_map_lock_try(dstmap) == true) { 2776 copy_ok = 1; 2777 if (!uvm_map_replace(dstmap, dstaddr, dstaddr+len, chain, 2778 nchain, nsize, &resentry)) { 2779 if (srcmap != dstmap) 2780 vm_map_unlock(dstmap); 2781 error = EIO; 2782 goto bad; 2783 } 2784 } else { 2785 copy_ok = 0; 2786 /* replace defered until step 7 */ 2787 } 2788 2789 /* 2790 * step 6: traverse the srcmap a second time to do the following: 2791 * - if we got a lock on the dstmap do pmap_copy 2792 * - if UVM_EXTRACT_REMOVE remove the entries 2793 * we make use of orig_entry and orig_fudge (saved in step 2) 2794 */ 2795 2796 if (copy_ok || (flags & UVM_EXTRACT_REMOVE)) { 2797 2798 /* purge possible stale hints from srcmap */ 2799 if (flags & UVM_EXTRACT_REMOVE) { 2800 SAVE_HINT(srcmap, srcmap->hint, orig_entry->prev); 2801 if (srcmap->first_free != &srcmap->header && 2802 srcmap->first_free->start >= start) 2803 srcmap->first_free = orig_entry->prev; 2804 } 2805 2806 entry = orig_entry; 2807 fudge = orig_fudge; 2808 deadentry = NULL; /* for UVM_EXTRACT_REMOVE */ 2809 2810 while (entry->start < end && entry != &srcmap->header) { 2811 if (copy_ok) { 2812 oldoffset = (entry->start + fudge) - start; 2813 elen = MIN(end, entry->end) - 2814 (entry->start + fudge); 2815 pmap_copy(dstmap->pmap, srcmap->pmap, 2816 dstaddr + oldoffset, elen, 2817 entry->start + fudge); 2818 } 2819 2820 /* we advance "entry" in the following if statement */ 2821 if (flags & UVM_EXTRACT_REMOVE) { 2822 uvm_map_lock_entry(entry); 2823 pmap_remove(srcmap->pmap, entry->start, 2824 entry->end); 2825 uvm_map_unlock_entry(entry); 2826 oldentry = entry; /* save entry */ 2827 entry = entry->next; /* advance */ 2828 uvm_map_entry_unlink(srcmap, oldentry); 2829 /* add to dead list */ 2830 oldentry->next = deadentry; 2831 deadentry = oldentry; 2832 } else { 2833 entry = entry->next; /* advance */ 2834 } 2835 2836 /* end of 'while' loop */ 2837 fudge = 0; 2838 } 2839 pmap_update(srcmap->pmap); 2840 2841 /* 2842 * unlock dstmap. we will dispose of deadentry in 2843 * step 7 if needed 2844 */ 2845 2846 if (copy_ok && srcmap != dstmap) 2847 vm_map_unlock(dstmap); 2848 2849 } else { 2850 deadentry = NULL; 2851 } 2852 2853 /* 2854 * step 7: we are done with the source map, unlock. if copy_ok 2855 * is 0 then we have not replaced the dummy mapping in dstmap yet 2856 * and we need to do so now. 2857 */ 2858 2859 vm_map_unlock(srcmap); 2860 if ((flags & UVM_EXTRACT_REMOVE) && deadentry) 2861 uvm_unmap_detach(deadentry, 0); /* dispose of old entries */ 2862 2863 /* now do the replacement if we didn't do it in step 5 */ 2864 if (copy_ok == 0) { 2865 vm_map_lock(dstmap); 2866 error = uvm_map_replace(dstmap, dstaddr, dstaddr+len, chain, 2867 nchain, nsize, &resentry); 2868 vm_map_unlock(dstmap); 2869 2870 if (error == false) { 2871 error = EIO; 2872 goto bad2; 2873 } 2874 } 2875 2876 if (resentry != NULL) 2877 uvm_mapent_free(resentry); 2878 2879 return (0); 2880 2881 /* 2882 * bad: failure recovery 2883 */ 2884 bad: 2885 vm_map_unlock(srcmap); 2886 bad2: /* src already unlocked */ 2887 if (chain) 2888 uvm_unmap_detach(chain, 2889 (flags & UVM_EXTRACT_QREF) ? AMAP_REFALL : 0); 2890 2891 if (resentry != NULL) 2892 uvm_mapent_free(resentry); 2893 2894 if ((flags & UVM_EXTRACT_RESERVED) == 0) { 2895 uvm_unmap(dstmap, dstaddr, dstaddr+len); /* ??? */ 2896 } 2897 return (error); 2898 } 2899 2900 /* end of extraction functions */ 2901 2902 /* 2903 * uvm_map_submap: punch down part of a map into a submap 2904 * 2905 * => only the kernel_map is allowed to be submapped 2906 * => the purpose of submapping is to break up the locking granularity 2907 * of a larger map 2908 * => the range specified must have been mapped previously with a uvm_map() 2909 * call [with uobj==NULL] to create a blank map entry in the main map. 2910 * [And it had better still be blank!] 2911 * => maps which contain submaps should never be copied or forked. 2912 * => to remove a submap, use uvm_unmap() on the main map 2913 * and then uvm_map_deallocate() the submap. 2914 * => main map must be unlocked. 2915 * => submap must have been init'd and have a zero reference count. 2916 * [need not be locked as we don't actually reference it] 2917 */ 2918 2919 int 2920 uvm_map_submap(struct vm_map *map, vaddr_t start, vaddr_t end, 2921 struct vm_map *submap) 2922 { 2923 struct vm_map_entry *entry; 2924 int error; 2925 2926 vm_map_lock(map); 2927 VM_MAP_RANGE_CHECK(map, start, end); 2928 2929 if (uvm_map_lookup_entry(map, start, &entry)) { 2930 UVM_MAP_CLIP_START(map, entry, start); 2931 UVM_MAP_CLIP_END(map, entry, end); /* to be safe */ 2932 } else { 2933 entry = NULL; 2934 } 2935 2936 if (entry != NULL && 2937 entry->start == start && entry->end == end && 2938 entry->object.uvm_obj == NULL && entry->aref.ar_amap == NULL && 2939 !UVM_ET_ISCOPYONWRITE(entry) && !UVM_ET_ISNEEDSCOPY(entry)) { 2940 entry->etype |= UVM_ET_SUBMAP; 2941 entry->object.sub_map = submap; 2942 entry->offset = 0; 2943 uvm_map_reference(submap); 2944 error = 0; 2945 } else { 2946 error = EINVAL; 2947 } 2948 vm_map_unlock(map); 2949 2950 return error; 2951 } 2952 2953 /* 2954 * uvm_map_protect: change map protection 2955 * 2956 * => set_max means set max_protection. 2957 * => map must be unlocked. 2958 */ 2959 2960 #define MASK(entry) (UVM_ET_ISCOPYONWRITE(entry) ? \ 2961 ~VM_PROT_WRITE : VM_PROT_ALL) 2962 2963 int 2964 uvm_map_protect(struct vm_map *map, vaddr_t start, vaddr_t end, 2965 vm_prot_t new_prot, bool set_max) 2966 { 2967 struct vm_map_entry *current, *entry; 2968 int error = 0; 2969 UVMHIST_FUNC("uvm_map_protect"); UVMHIST_CALLED(maphist); 2970 UVMHIST_LOG(maphist,"(map=%p,start=%#lx,end=%#lx,new_prot=%#x)", 2971 map, start, end, new_prot); 2972 2973 vm_map_lock(map); 2974 VM_MAP_RANGE_CHECK(map, start, end); 2975 if (uvm_map_lookup_entry(map, start, &entry)) { 2976 UVM_MAP_CLIP_START(map, entry, start); 2977 } else { 2978 entry = entry->next; 2979 } 2980 2981 /* 2982 * make a first pass to check for protection violations. 2983 */ 2984 2985 current = entry; 2986 while ((current != &map->header) && (current->start < end)) { 2987 if (UVM_ET_ISSUBMAP(current)) { 2988 error = EINVAL; 2989 goto out; 2990 } 2991 if ((new_prot & current->max_protection) != new_prot) { 2992 error = EACCES; 2993 goto out; 2994 } 2995 /* 2996 * Don't allow VM_PROT_EXECUTE to be set on entries that 2997 * point to vnodes that are associated with a NOEXEC file 2998 * system. 2999 */ 3000 if (UVM_ET_ISOBJ(current) && 3001 UVM_OBJ_IS_VNODE(current->object.uvm_obj)) { 3002 struct vnode *vp = 3003 (struct vnode *) current->object.uvm_obj; 3004 3005 if ((new_prot & VM_PROT_EXECUTE) != 0 && 3006 (vp->v_mount->mnt_flag & MNT_NOEXEC) != 0) { 3007 error = EACCES; 3008 goto out; 3009 } 3010 } 3011 3012 current = current->next; 3013 } 3014 3015 /* go back and fix up protections (no need to clip this time). */ 3016 3017 current = entry; 3018 while ((current != &map->header) && (current->start < end)) { 3019 vm_prot_t old_prot; 3020 3021 UVM_MAP_CLIP_END(map, current, end); 3022 old_prot = current->protection; 3023 if (set_max) 3024 current->protection = 3025 (current->max_protection = new_prot) & old_prot; 3026 else 3027 current->protection = new_prot; 3028 3029 /* 3030 * update physical map if necessary. worry about copy-on-write 3031 * here -- CHECK THIS XXX 3032 */ 3033 3034 if (current->protection != old_prot) { 3035 /* update pmap! */ 3036 uvm_map_lock_entry(current); 3037 pmap_protect(map->pmap, current->start, current->end, 3038 current->protection & MASK(entry)); 3039 uvm_map_unlock_entry(current); 3040 3041 /* 3042 * If this entry points at a vnode, and the 3043 * protection includes VM_PROT_EXECUTE, mark 3044 * the vnode as VEXECMAP. 3045 */ 3046 if (UVM_ET_ISOBJ(current)) { 3047 struct uvm_object *uobj = 3048 current->object.uvm_obj; 3049 3050 if (UVM_OBJ_IS_VNODE(uobj) && 3051 (current->protection & VM_PROT_EXECUTE)) { 3052 vn_markexec((struct vnode *) uobj); 3053 } 3054 } 3055 } 3056 3057 /* 3058 * If the map is configured to lock any future mappings, 3059 * wire this entry now if the old protection was VM_PROT_NONE 3060 * and the new protection is not VM_PROT_NONE. 3061 */ 3062 3063 if ((map->flags & VM_MAP_WIREFUTURE) != 0 && 3064 VM_MAPENT_ISWIRED(entry) == 0 && 3065 old_prot == VM_PROT_NONE && 3066 new_prot != VM_PROT_NONE) { 3067 if (uvm_map_pageable(map, entry->start, 3068 entry->end, false, 3069 UVM_LK_ENTER|UVM_LK_EXIT) != 0) { 3070 3071 /* 3072 * If locking the entry fails, remember the 3073 * error if it's the first one. Note we 3074 * still continue setting the protection in 3075 * the map, but will return the error 3076 * condition regardless. 3077 * 3078 * XXX Ignore what the actual error is, 3079 * XXX just call it a resource shortage 3080 * XXX so that it doesn't get confused 3081 * XXX what uvm_map_protect() itself would 3082 * XXX normally return. 3083 */ 3084 3085 error = ENOMEM; 3086 } 3087 } 3088 current = current->next; 3089 } 3090 pmap_update(map->pmap); 3091 3092 out: 3093 vm_map_unlock(map); 3094 3095 UVMHIST_LOG(maphist, "<- done, error=%d",error,0,0,0); 3096 return error; 3097 } 3098 3099 #undef MASK 3100 3101 /* 3102 * uvm_map_inherit: set inheritance code for range of addrs in map. 3103 * 3104 * => map must be unlocked 3105 * => note that the inherit code is used during a "fork". see fork 3106 * code for details. 3107 */ 3108 3109 int 3110 uvm_map_inherit(struct vm_map *map, vaddr_t start, vaddr_t end, 3111 vm_inherit_t new_inheritance) 3112 { 3113 struct vm_map_entry *entry, *temp_entry; 3114 UVMHIST_FUNC("uvm_map_inherit"); UVMHIST_CALLED(maphist); 3115 UVMHIST_LOG(maphist,"(map=%p,start=%#lx,end=%#lx,new_inh=%#x)", 3116 map, start, end, new_inheritance); 3117 3118 switch (new_inheritance) { 3119 case MAP_INHERIT_NONE: 3120 case MAP_INHERIT_COPY: 3121 case MAP_INHERIT_SHARE: 3122 case MAP_INHERIT_ZERO: 3123 break; 3124 default: 3125 UVMHIST_LOG(maphist,"<- done (INVALID ARG)",0,0,0,0); 3126 return EINVAL; 3127 } 3128 3129 vm_map_lock(map); 3130 VM_MAP_RANGE_CHECK(map, start, end); 3131 if (uvm_map_lookup_entry(map, start, &temp_entry)) { 3132 entry = temp_entry; 3133 UVM_MAP_CLIP_START(map, entry, start); 3134 } else { 3135 entry = temp_entry->next; 3136 } 3137 while ((entry != &map->header) && (entry->start < end)) { 3138 UVM_MAP_CLIP_END(map, entry, end); 3139 entry->inheritance = new_inheritance; 3140 entry = entry->next; 3141 } 3142 vm_map_unlock(map); 3143 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 3144 return 0; 3145 } 3146 3147 /* 3148 * uvm_map_advice: set advice code for range of addrs in map. 3149 * 3150 * => map must be unlocked 3151 */ 3152 3153 int 3154 uvm_map_advice(struct vm_map *map, vaddr_t start, vaddr_t end, int new_advice) 3155 { 3156 struct vm_map_entry *entry, *temp_entry; 3157 UVMHIST_FUNC("uvm_map_advice"); UVMHIST_CALLED(maphist); 3158 UVMHIST_LOG(maphist,"(map=%p,start=%#lx,end=%#lx,new_adv=%#x)", 3159 map, start, end, new_advice); 3160 3161 vm_map_lock(map); 3162 VM_MAP_RANGE_CHECK(map, start, end); 3163 if (uvm_map_lookup_entry(map, start, &temp_entry)) { 3164 entry = temp_entry; 3165 UVM_MAP_CLIP_START(map, entry, start); 3166 } else { 3167 entry = temp_entry->next; 3168 } 3169 3170 /* 3171 * XXXJRT: disallow holes? 3172 */ 3173 3174 while ((entry != &map->header) && (entry->start < end)) { 3175 UVM_MAP_CLIP_END(map, entry, end); 3176 3177 switch (new_advice) { 3178 case MADV_NORMAL: 3179 case MADV_RANDOM: 3180 case MADV_SEQUENTIAL: 3181 /* nothing special here */ 3182 break; 3183 3184 default: 3185 vm_map_unlock(map); 3186 UVMHIST_LOG(maphist,"<- done (INVALID ARG)",0,0,0,0); 3187 return EINVAL; 3188 } 3189 entry->advice = new_advice; 3190 entry = entry->next; 3191 } 3192 3193 vm_map_unlock(map); 3194 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 3195 return 0; 3196 } 3197 3198 /* 3199 * uvm_map_willneed: apply MADV_WILLNEED 3200 */ 3201 3202 int 3203 uvm_map_willneed(struct vm_map *map, vaddr_t start, vaddr_t end) 3204 { 3205 struct vm_map_entry *entry; 3206 UVMHIST_FUNC("uvm_map_willneed"); UVMHIST_CALLED(maphist); 3207 UVMHIST_LOG(maphist,"(map=%p,start=%#lx,end=%#lx)", 3208 map, start, end, 0); 3209 3210 vm_map_lock_read(map); 3211 VM_MAP_RANGE_CHECK(map, start, end); 3212 if (!uvm_map_lookup_entry(map, start, &entry)) { 3213 entry = entry->next; 3214 } 3215 while (entry->start < end) { 3216 struct vm_amap * const amap = entry->aref.ar_amap; 3217 struct uvm_object * const uobj = entry->object.uvm_obj; 3218 3219 KASSERT(entry != &map->header); 3220 KASSERT(start < entry->end); 3221 /* 3222 * For now, we handle only the easy but commonly-requested case. 3223 * ie. start prefetching of backing uobj pages. 3224 * 3225 * XXX It might be useful to pmap_enter() the already-in-core 3226 * pages by inventing a "weak" mode for uvm_fault() which would 3227 * only do the PGO_LOCKED pgo_get(). 3228 */ 3229 if (UVM_ET_ISOBJ(entry) && amap == NULL && uobj != NULL) { 3230 off_t offset; 3231 off_t size; 3232 3233 offset = entry->offset; 3234 if (start < entry->start) { 3235 offset += entry->start - start; 3236 } 3237 size = entry->offset + (entry->end - entry->start); 3238 if (entry->end < end) { 3239 size -= end - entry->end; 3240 } 3241 uvm_readahead(uobj, offset, size); 3242 } 3243 entry = entry->next; 3244 } 3245 vm_map_unlock_read(map); 3246 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 3247 return 0; 3248 } 3249 3250 /* 3251 * uvm_map_pageable: sets the pageability of a range in a map. 3252 * 3253 * => wires map entries. should not be used for transient page locking. 3254 * for that, use uvm_fault_wire()/uvm_fault_unwire() (see uvm_vslock()). 3255 * => regions specified as not pageable require lock-down (wired) memory 3256 * and page tables. 3257 * => map must never be read-locked 3258 * => if islocked is true, map is already write-locked 3259 * => we always unlock the map, since we must downgrade to a read-lock 3260 * to call uvm_fault_wire() 3261 * => XXXCDC: check this and try and clean it up. 3262 */ 3263 3264 int 3265 uvm_map_pageable(struct vm_map *map, vaddr_t start, vaddr_t end, 3266 bool new_pageable, int lockflags) 3267 { 3268 struct vm_map_entry *entry, *start_entry, *failed_entry; 3269 int rv; 3270 #ifdef DIAGNOSTIC 3271 u_int timestamp_save; 3272 #endif 3273 UVMHIST_FUNC("uvm_map_pageable"); UVMHIST_CALLED(maphist); 3274 UVMHIST_LOG(maphist,"(map=%p,start=%#lx,end=%#lx,new_pageable=%u)", 3275 map, start, end, new_pageable); 3276 KASSERT(map->flags & VM_MAP_PAGEABLE); 3277 3278 if ((lockflags & UVM_LK_ENTER) == 0) 3279 vm_map_lock(map); 3280 VM_MAP_RANGE_CHECK(map, start, end); 3281 3282 /* 3283 * only one pageability change may take place at one time, since 3284 * uvm_fault_wire assumes it will be called only once for each 3285 * wiring/unwiring. therefore, we have to make sure we're actually 3286 * changing the pageability for the entire region. we do so before 3287 * making any changes. 3288 */ 3289 3290 if (uvm_map_lookup_entry(map, start, &start_entry) == false) { 3291 if ((lockflags & UVM_LK_EXIT) == 0) 3292 vm_map_unlock(map); 3293 3294 UVMHIST_LOG(maphist,"<- done (fault)",0,0,0,0); 3295 return EFAULT; 3296 } 3297 entry = start_entry; 3298 3299 /* 3300 * handle wiring and unwiring separately. 3301 */ 3302 3303 if (new_pageable) { /* unwire */ 3304 UVM_MAP_CLIP_START(map, entry, start); 3305 3306 /* 3307 * unwiring. first ensure that the range to be unwired is 3308 * really wired down and that there are no holes. 3309 */ 3310 3311 while ((entry != &map->header) && (entry->start < end)) { 3312 if (entry->wired_count == 0 || 3313 (entry->end < end && 3314 (entry->next == &map->header || 3315 entry->next->start > entry->end))) { 3316 if ((lockflags & UVM_LK_EXIT) == 0) 3317 vm_map_unlock(map); 3318 UVMHIST_LOG(maphist, "<- done (INVAL)",0,0,0,0); 3319 return EINVAL; 3320 } 3321 entry = entry->next; 3322 } 3323 3324 /* 3325 * POSIX 1003.1b - a single munlock call unlocks a region, 3326 * regardless of the number of mlock calls made on that 3327 * region. 3328 */ 3329 3330 entry = start_entry; 3331 while ((entry != &map->header) && (entry->start < end)) { 3332 UVM_MAP_CLIP_END(map, entry, end); 3333 if (VM_MAPENT_ISWIRED(entry)) 3334 uvm_map_entry_unwire(map, entry); 3335 entry = entry->next; 3336 } 3337 if ((lockflags & UVM_LK_EXIT) == 0) 3338 vm_map_unlock(map); 3339 UVMHIST_LOG(maphist,"<- done (OK UNWIRE)",0,0,0,0); 3340 return 0; 3341 } 3342 3343 /* 3344 * wire case: in two passes [XXXCDC: ugly block of code here] 3345 * 3346 * 1: holding the write lock, we create any anonymous maps that need 3347 * to be created. then we clip each map entry to the region to 3348 * be wired and increment its wiring count. 3349 * 3350 * 2: we downgrade to a read lock, and call uvm_fault_wire to fault 3351 * in the pages for any newly wired area (wired_count == 1). 3352 * 3353 * downgrading to a read lock for uvm_fault_wire avoids a possible 3354 * deadlock with another thread that may have faulted on one of 3355 * the pages to be wired (it would mark the page busy, blocking 3356 * us, then in turn block on the map lock that we hold). because 3357 * of problems in the recursive lock package, we cannot upgrade 3358 * to a write lock in vm_map_lookup. thus, any actions that 3359 * require the write lock must be done beforehand. because we 3360 * keep the read lock on the map, the copy-on-write status of the 3361 * entries we modify here cannot change. 3362 */ 3363 3364 while ((entry != &map->header) && (entry->start < end)) { 3365 if (VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 3366 3367 /* 3368 * perform actions of vm_map_lookup that need the 3369 * write lock on the map: create an anonymous map 3370 * for a copy-on-write region, or an anonymous map 3371 * for a zero-fill region. (XXXCDC: submap case 3372 * ok?) 3373 */ 3374 3375 if (!UVM_ET_ISSUBMAP(entry)) { /* not submap */ 3376 if (UVM_ET_ISNEEDSCOPY(entry) && 3377 ((entry->max_protection & VM_PROT_WRITE) || 3378 (entry->object.uvm_obj == NULL))) { 3379 amap_copy(map, entry, 0, start, end); 3380 /* XXXCDC: wait OK? */ 3381 } 3382 } 3383 } 3384 UVM_MAP_CLIP_START(map, entry, start); 3385 UVM_MAP_CLIP_END(map, entry, end); 3386 entry->wired_count++; 3387 3388 /* 3389 * Check for holes 3390 */ 3391 3392 if (entry->protection == VM_PROT_NONE || 3393 (entry->end < end && 3394 (entry->next == &map->header || 3395 entry->next->start > entry->end))) { 3396 3397 /* 3398 * found one. amap creation actions do not need to 3399 * be undone, but the wired counts need to be restored. 3400 */ 3401 3402 while (entry != &map->header && entry->end > start) { 3403 entry->wired_count--; 3404 entry = entry->prev; 3405 } 3406 if ((lockflags & UVM_LK_EXIT) == 0) 3407 vm_map_unlock(map); 3408 UVMHIST_LOG(maphist,"<- done (INVALID WIRE)",0,0,0,0); 3409 return EINVAL; 3410 } 3411 entry = entry->next; 3412 } 3413 3414 /* 3415 * Pass 2. 3416 */ 3417 3418 #ifdef DIAGNOSTIC 3419 timestamp_save = map->timestamp; 3420 #endif 3421 vm_map_busy(map); 3422 vm_map_unlock(map); 3423 3424 rv = 0; 3425 entry = start_entry; 3426 while (entry != &map->header && entry->start < end) { 3427 if (entry->wired_count == 1) { 3428 rv = uvm_fault_wire(map, entry->start, entry->end, 3429 entry->max_protection, 1); 3430 if (rv) { 3431 3432 /* 3433 * wiring failed. break out of the loop. 3434 * we'll clean up the map below, once we 3435 * have a write lock again. 3436 */ 3437 3438 break; 3439 } 3440 } 3441 entry = entry->next; 3442 } 3443 3444 if (rv) { /* failed? */ 3445 3446 /* 3447 * Get back to an exclusive (write) lock. 3448 */ 3449 3450 vm_map_lock(map); 3451 vm_map_unbusy(map); 3452 3453 #ifdef DIAGNOSTIC 3454 if (timestamp_save + 1 != map->timestamp) 3455 panic("uvm_map_pageable: stale map"); 3456 #endif 3457 3458 /* 3459 * first drop the wiring count on all the entries 3460 * which haven't actually been wired yet. 3461 */ 3462 3463 failed_entry = entry; 3464 while (entry != &map->header && entry->start < end) { 3465 entry->wired_count--; 3466 entry = entry->next; 3467 } 3468 3469 /* 3470 * now, unwire all the entries that were successfully 3471 * wired above. 3472 */ 3473 3474 entry = start_entry; 3475 while (entry != failed_entry) { 3476 entry->wired_count--; 3477 if (VM_MAPENT_ISWIRED(entry) == 0) 3478 uvm_map_entry_unwire(map, entry); 3479 entry = entry->next; 3480 } 3481 if ((lockflags & UVM_LK_EXIT) == 0) 3482 vm_map_unlock(map); 3483 UVMHIST_LOG(maphist, "<- done (RV=%d)", rv,0,0,0); 3484 return (rv); 3485 } 3486 3487 if ((lockflags & UVM_LK_EXIT) == 0) { 3488 vm_map_unbusy(map); 3489 } else { 3490 3491 /* 3492 * Get back to an exclusive (write) lock. 3493 */ 3494 3495 vm_map_lock(map); 3496 vm_map_unbusy(map); 3497 } 3498 3499 UVMHIST_LOG(maphist,"<- done (OK WIRE)",0,0,0,0); 3500 return 0; 3501 } 3502 3503 /* 3504 * uvm_map_pageable_all: special case of uvm_map_pageable - affects 3505 * all mapped regions. 3506 * 3507 * => map must not be locked. 3508 * => if no flags are specified, all regions are unwired. 3509 * => XXXJRT: has some of the same problems as uvm_map_pageable() above. 3510 */ 3511 3512 int 3513 uvm_map_pageable_all(struct vm_map *map, int flags, vsize_t limit) 3514 { 3515 struct vm_map_entry *entry, *failed_entry; 3516 vsize_t size; 3517 int rv; 3518 #ifdef DIAGNOSTIC 3519 u_int timestamp_save; 3520 #endif 3521 UVMHIST_FUNC("uvm_map_pageable_all"); UVMHIST_CALLED(maphist); 3522 UVMHIST_LOG(maphist,"(map=%p,flags=%#x)", map, flags, 0, 0); 3523 3524 KASSERT(map->flags & VM_MAP_PAGEABLE); 3525 3526 vm_map_lock(map); 3527 3528 /* 3529 * handle wiring and unwiring separately. 3530 */ 3531 3532 if (flags == 0) { /* unwire */ 3533 3534 /* 3535 * POSIX 1003.1b -- munlockall unlocks all regions, 3536 * regardless of how many times mlockall has been called. 3537 */ 3538 3539 for (entry = map->header.next; entry != &map->header; 3540 entry = entry->next) { 3541 if (VM_MAPENT_ISWIRED(entry)) 3542 uvm_map_entry_unwire(map, entry); 3543 } 3544 map->flags &= ~VM_MAP_WIREFUTURE; 3545 vm_map_unlock(map); 3546 UVMHIST_LOG(maphist,"<- done (OK UNWIRE)",0,0,0,0); 3547 return 0; 3548 } 3549 3550 if (flags & MCL_FUTURE) { 3551 3552 /* 3553 * must wire all future mappings; remember this. 3554 */ 3555 3556 map->flags |= VM_MAP_WIREFUTURE; 3557 } 3558 3559 if ((flags & MCL_CURRENT) == 0) { 3560 3561 /* 3562 * no more work to do! 3563 */ 3564 3565 UVMHIST_LOG(maphist,"<- done (OK no wire)",0,0,0,0); 3566 vm_map_unlock(map); 3567 return 0; 3568 } 3569 3570 /* 3571 * wire case: in three passes [XXXCDC: ugly block of code here] 3572 * 3573 * 1: holding the write lock, count all pages mapped by non-wired 3574 * entries. if this would cause us to go over our limit, we fail. 3575 * 3576 * 2: still holding the write lock, we create any anonymous maps that 3577 * need to be created. then we increment its wiring count. 3578 * 3579 * 3: we downgrade to a read lock, and call uvm_fault_wire to fault 3580 * in the pages for any newly wired area (wired_count == 1). 3581 * 3582 * downgrading to a read lock for uvm_fault_wire avoids a possible 3583 * deadlock with another thread that may have faulted on one of 3584 * the pages to be wired (it would mark the page busy, blocking 3585 * us, then in turn block on the map lock that we hold). because 3586 * of problems in the recursive lock package, we cannot upgrade 3587 * to a write lock in vm_map_lookup. thus, any actions that 3588 * require the write lock must be done beforehand. because we 3589 * keep the read lock on the map, the copy-on-write status of the 3590 * entries we modify here cannot change. 3591 */ 3592 3593 for (size = 0, entry = map->header.next; entry != &map->header; 3594 entry = entry->next) { 3595 if (entry->protection != VM_PROT_NONE && 3596 VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 3597 size += entry->end - entry->start; 3598 } 3599 } 3600 3601 if (atop(size) + uvmexp.wired > uvmexp.wiredmax) { 3602 vm_map_unlock(map); 3603 return ENOMEM; 3604 } 3605 3606 if (limit != 0 && 3607 (size + ptoa(pmap_wired_count(vm_map_pmap(map))) > limit)) { 3608 vm_map_unlock(map); 3609 return ENOMEM; 3610 } 3611 3612 /* 3613 * Pass 2. 3614 */ 3615 3616 for (entry = map->header.next; entry != &map->header; 3617 entry = entry->next) { 3618 if (entry->protection == VM_PROT_NONE) 3619 continue; 3620 if (VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 3621 3622 /* 3623 * perform actions of vm_map_lookup that need the 3624 * write lock on the map: create an anonymous map 3625 * for a copy-on-write region, or an anonymous map 3626 * for a zero-fill region. (XXXCDC: submap case 3627 * ok?) 3628 */ 3629 3630 if (!UVM_ET_ISSUBMAP(entry)) { /* not submap */ 3631 if (UVM_ET_ISNEEDSCOPY(entry) && 3632 ((entry->max_protection & VM_PROT_WRITE) || 3633 (entry->object.uvm_obj == NULL))) { 3634 amap_copy(map, entry, 0, entry->start, 3635 entry->end); 3636 /* XXXCDC: wait OK? */ 3637 } 3638 } 3639 } 3640 entry->wired_count++; 3641 } 3642 3643 /* 3644 * Pass 3. 3645 */ 3646 3647 #ifdef DIAGNOSTIC 3648 timestamp_save = map->timestamp; 3649 #endif 3650 vm_map_busy(map); 3651 vm_map_unlock(map); 3652 3653 rv = 0; 3654 for (entry = map->header.next; entry != &map->header; 3655 entry = entry->next) { 3656 if (entry->wired_count == 1) { 3657 rv = uvm_fault_wire(map, entry->start, entry->end, 3658 entry->max_protection, 1); 3659 if (rv) { 3660 3661 /* 3662 * wiring failed. break out of the loop. 3663 * we'll clean up the map below, once we 3664 * have a write lock again. 3665 */ 3666 3667 break; 3668 } 3669 } 3670 } 3671 3672 if (rv) { 3673 3674 /* 3675 * Get back an exclusive (write) lock. 3676 */ 3677 3678 vm_map_lock(map); 3679 vm_map_unbusy(map); 3680 3681 #ifdef DIAGNOSTIC 3682 if (timestamp_save + 1 != map->timestamp) 3683 panic("uvm_map_pageable_all: stale map"); 3684 #endif 3685 3686 /* 3687 * first drop the wiring count on all the entries 3688 * which haven't actually been wired yet. 3689 * 3690 * Skip VM_PROT_NONE entries like we did above. 3691 */ 3692 3693 failed_entry = entry; 3694 for (/* nothing */; entry != &map->header; 3695 entry = entry->next) { 3696 if (entry->protection == VM_PROT_NONE) 3697 continue; 3698 entry->wired_count--; 3699 } 3700 3701 /* 3702 * now, unwire all the entries that were successfully 3703 * wired above. 3704 * 3705 * Skip VM_PROT_NONE entries like we did above. 3706 */ 3707 3708 for (entry = map->header.next; entry != failed_entry; 3709 entry = entry->next) { 3710 if (entry->protection == VM_PROT_NONE) 3711 continue; 3712 entry->wired_count--; 3713 if (VM_MAPENT_ISWIRED(entry)) 3714 uvm_map_entry_unwire(map, entry); 3715 } 3716 vm_map_unlock(map); 3717 UVMHIST_LOG(maphist,"<- done (RV=%d)", rv,0,0,0); 3718 return (rv); 3719 } 3720 3721 vm_map_unbusy(map); 3722 3723 UVMHIST_LOG(maphist,"<- done (OK WIRE)",0,0,0,0); 3724 return 0; 3725 } 3726 3727 /* 3728 * uvm_map_clean: clean out a map range 3729 * 3730 * => valid flags: 3731 * if (flags & PGO_CLEANIT): dirty pages are cleaned first 3732 * if (flags & PGO_SYNCIO): dirty pages are written synchronously 3733 * if (flags & PGO_DEACTIVATE): any cached pages are deactivated after clean 3734 * if (flags & PGO_FREE): any cached pages are freed after clean 3735 * => returns an error if any part of the specified range isn't mapped 3736 * => never a need to flush amap layer since the anonymous memory has 3737 * no permanent home, but may deactivate pages there 3738 * => called from sys_msync() and sys_madvise() 3739 * => caller must not write-lock map (read OK). 3740 * => we may sleep while cleaning if SYNCIO [with map read-locked] 3741 */ 3742 3743 int 3744 uvm_map_clean(struct vm_map *map, vaddr_t start, vaddr_t end, int flags) 3745 { 3746 struct vm_map_entry *current, *entry; 3747 struct uvm_object *uobj; 3748 struct vm_amap *amap; 3749 struct vm_anon *anon, *anon_tofree; 3750 struct vm_page *pg; 3751 vaddr_t offset; 3752 vsize_t size; 3753 voff_t uoff; 3754 int error, refs; 3755 UVMHIST_FUNC("uvm_map_clean"); UVMHIST_CALLED(maphist); 3756 3757 UVMHIST_LOG(maphist,"(map=%p,start=%#lx,end=%#lx,flags=%#x)", 3758 map, start, end, flags); 3759 KASSERT((flags & (PGO_FREE|PGO_DEACTIVATE)) != 3760 (PGO_FREE|PGO_DEACTIVATE)); 3761 3762 vm_map_lock_read(map); 3763 VM_MAP_RANGE_CHECK(map, start, end); 3764 if (uvm_map_lookup_entry(map, start, &entry) == false) { 3765 vm_map_unlock_read(map); 3766 return EFAULT; 3767 } 3768 3769 /* 3770 * Make a first pass to check for holes and wiring problems. 3771 */ 3772 3773 for (current = entry; current->start < end; current = current->next) { 3774 if (UVM_ET_ISSUBMAP(current)) { 3775 vm_map_unlock_read(map); 3776 return EINVAL; 3777 } 3778 if ((flags & PGO_FREE) != 0 && VM_MAPENT_ISWIRED(entry)) { 3779 vm_map_unlock_read(map); 3780 return EBUSY; 3781 } 3782 if (end <= current->end) { 3783 break; 3784 } 3785 if (current->end != current->next->start) { 3786 vm_map_unlock_read(map); 3787 return EFAULT; 3788 } 3789 } 3790 3791 error = 0; 3792 for (current = entry; start < end; current = current->next) { 3793 amap = current->aref.ar_amap; /* upper layer */ 3794 uobj = current->object.uvm_obj; /* lower layer */ 3795 KASSERT(start >= current->start); 3796 3797 /* 3798 * No amap cleaning necessary if: 3799 * 3800 * (1) There's no amap. 3801 * 3802 * (2) We're not deactivating or freeing pages. 3803 */ 3804 3805 if (amap == NULL || (flags & (PGO_DEACTIVATE|PGO_FREE)) == 0) 3806 goto flush_object; 3807 3808 offset = start - current->start; 3809 size = MIN(end, current->end) - start; 3810 anon_tofree = NULL; 3811 3812 amap_lock(amap); 3813 for ( ; size != 0; size -= PAGE_SIZE, offset += PAGE_SIZE) { 3814 anon = amap_lookup(¤t->aref, offset); 3815 if (anon == NULL) 3816 continue; 3817 3818 KASSERT(anon->an_lock == amap->am_lock); 3819 pg = anon->an_page; 3820 if (pg == NULL) { 3821 continue; 3822 } 3823 if (pg->flags & PG_BUSY) { 3824 continue; 3825 } 3826 3827 switch (flags & (PGO_CLEANIT|PGO_FREE|PGO_DEACTIVATE)) { 3828 3829 /* 3830 * In these first 3 cases, we just deactivate the page. 3831 */ 3832 3833 case PGO_CLEANIT|PGO_FREE: 3834 case PGO_CLEANIT|PGO_DEACTIVATE: 3835 case PGO_DEACTIVATE: 3836 deactivate_it: 3837 /* 3838 * skip the page if it's loaned or wired, 3839 * since it shouldn't be on a paging queue 3840 * at all in these cases. 3841 */ 3842 3843 mutex_enter(&uvm_pageqlock); 3844 if (pg->loan_count != 0 || 3845 pg->wire_count != 0) { 3846 mutex_exit(&uvm_pageqlock); 3847 continue; 3848 } 3849 KASSERT(pg->uanon == anon); 3850 uvm_pagedeactivate(pg); 3851 mutex_exit(&uvm_pageqlock); 3852 continue; 3853 3854 case PGO_FREE: 3855 3856 /* 3857 * If there are multiple references to 3858 * the amap, just deactivate the page. 3859 */ 3860 3861 if (amap_refs(amap) > 1) 3862 goto deactivate_it; 3863 3864 /* skip the page if it's wired */ 3865 if (pg->wire_count != 0) { 3866 continue; 3867 } 3868 amap_unadd(¤t->aref, offset); 3869 refs = --anon->an_ref; 3870 if (refs == 0) { 3871 anon->an_link = anon_tofree; 3872 anon_tofree = anon; 3873 } 3874 continue; 3875 } 3876 } 3877 uvm_anon_freelst(amap, anon_tofree); 3878 3879 flush_object: 3880 /* 3881 * flush pages if we've got a valid backing object. 3882 * note that we must always clean object pages before 3883 * freeing them since otherwise we could reveal stale 3884 * data from files. 3885 */ 3886 3887 uoff = current->offset + (start - current->start); 3888 size = MIN(end, current->end) - start; 3889 if (uobj != NULL) { 3890 mutex_enter(uobj->vmobjlock); 3891 if (uobj->pgops->pgo_put != NULL) 3892 error = (uobj->pgops->pgo_put)(uobj, uoff, 3893 uoff + size, flags | PGO_CLEANIT); 3894 else 3895 error = 0; 3896 } 3897 start += size; 3898 } 3899 vm_map_unlock_read(map); 3900 return (error); 3901 } 3902 3903 3904 /* 3905 * uvm_map_checkprot: check protection in map 3906 * 3907 * => must allow specified protection in a fully allocated region. 3908 * => map must be read or write locked by caller. 3909 */ 3910 3911 bool 3912 uvm_map_checkprot(struct vm_map *map, vaddr_t start, vaddr_t end, 3913 vm_prot_t protection) 3914 { 3915 struct vm_map_entry *entry; 3916 struct vm_map_entry *tmp_entry; 3917 3918 if (!uvm_map_lookup_entry(map, start, &tmp_entry)) { 3919 return (false); 3920 } 3921 entry = tmp_entry; 3922 while (start < end) { 3923 if (entry == &map->header) { 3924 return (false); 3925 } 3926 3927 /* 3928 * no holes allowed 3929 */ 3930 3931 if (start < entry->start) { 3932 return (false); 3933 } 3934 3935 /* 3936 * check protection associated with entry 3937 */ 3938 3939 if ((entry->protection & protection) != protection) { 3940 return (false); 3941 } 3942 start = entry->end; 3943 entry = entry->next; 3944 } 3945 return (true); 3946 } 3947 3948 /* 3949 * uvmspace_alloc: allocate a vmspace structure. 3950 * 3951 * - structure includes vm_map and pmap 3952 * - XXX: no locking on this structure 3953 * - refcnt set to 1, rest must be init'd by caller 3954 */ 3955 struct vmspace * 3956 uvmspace_alloc(vaddr_t vmin, vaddr_t vmax, bool topdown) 3957 { 3958 struct vmspace *vm; 3959 UVMHIST_FUNC("uvmspace_alloc"); UVMHIST_CALLED(maphist); 3960 3961 vm = pool_cache_get(&uvm_vmspace_cache, PR_WAITOK); 3962 uvmspace_init(vm, NULL, vmin, vmax, topdown); 3963 UVMHIST_LOG(maphist,"<- done (vm=%p)", vm,0,0,0); 3964 return (vm); 3965 } 3966 3967 /* 3968 * uvmspace_init: initialize a vmspace structure. 3969 * 3970 * - XXX: no locking on this structure 3971 * - refcnt set to 1, rest must be init'd by caller 3972 */ 3973 void 3974 uvmspace_init(struct vmspace *vm, struct pmap *pmap, vaddr_t vmin, 3975 vaddr_t vmax, bool topdown) 3976 { 3977 UVMHIST_FUNC("uvmspace_init"); UVMHIST_CALLED(maphist); 3978 3979 UVMHIST_LOG(maphist, "(vm=%p, pmap=%p, vmin=%#lx, vmax=%#lx", 3980 vm, pmap, vmin, vmax); 3981 UVMHIST_LOG(maphist, " topdown=%u)", topdown, 0, 0, 0); 3982 3983 memset(vm, 0, sizeof(*vm)); 3984 uvm_map_setup(&vm->vm_map, vmin, vmax, VM_MAP_PAGEABLE 3985 | (topdown ? VM_MAP_TOPDOWN : 0) 3986 ); 3987 if (pmap) 3988 pmap_reference(pmap); 3989 else 3990 pmap = pmap_create(); 3991 vm->vm_map.pmap = pmap; 3992 vm->vm_refcnt = 1; 3993 UVMHIST_LOG(maphist,"<- done",0,0,0,0); 3994 } 3995 3996 /* 3997 * uvmspace_share: share a vmspace between two processes 3998 * 3999 * - used for vfork, threads(?) 4000 */ 4001 4002 void 4003 uvmspace_share(struct proc *p1, struct proc *p2) 4004 { 4005 4006 uvmspace_addref(p1->p_vmspace); 4007 p2->p_vmspace = p1->p_vmspace; 4008 } 4009 4010 #if 0 4011 4012 /* 4013 * uvmspace_unshare: ensure that process "p" has its own, unshared, vmspace 4014 * 4015 * - XXX: no locking on vmspace 4016 */ 4017 4018 void 4019 uvmspace_unshare(struct lwp *l) 4020 { 4021 struct proc *p = l->l_proc; 4022 struct vmspace *nvm, *ovm = p->p_vmspace; 4023 4024 if (ovm->vm_refcnt == 1) 4025 /* nothing to do: vmspace isn't shared in the first place */ 4026 return; 4027 4028 /* make a new vmspace, still holding old one */ 4029 nvm = uvmspace_fork(ovm); 4030 4031 kpreempt_disable(); 4032 pmap_deactivate(l); /* unbind old vmspace */ 4033 p->p_vmspace = nvm; 4034 pmap_activate(l); /* switch to new vmspace */ 4035 kpreempt_enable(); 4036 4037 uvmspace_free(ovm); /* drop reference to old vmspace */ 4038 } 4039 4040 #endif 4041 4042 4043 /* 4044 * uvmspace_spawn: a new process has been spawned and needs a vmspace 4045 */ 4046 4047 void 4048 uvmspace_spawn(struct lwp *l, vaddr_t start, vaddr_t end, bool topdown) 4049 { 4050 struct proc *p = l->l_proc; 4051 struct vmspace *nvm; 4052 4053 #ifdef __HAVE_CPU_VMSPACE_EXEC 4054 cpu_vmspace_exec(l, start, end); 4055 #endif 4056 4057 nvm = uvmspace_alloc(start, end, topdown); 4058 kpreempt_disable(); 4059 p->p_vmspace = nvm; 4060 pmap_activate(l); 4061 kpreempt_enable(); 4062 } 4063 4064 /* 4065 * uvmspace_exec: the process wants to exec a new program 4066 */ 4067 4068 void 4069 uvmspace_exec(struct lwp *l, vaddr_t start, vaddr_t end, bool topdown) 4070 { 4071 struct proc *p = l->l_proc; 4072 struct vmspace *nvm, *ovm = p->p_vmspace; 4073 struct vm_map *map; 4074 4075 KASSERT(ovm != NULL); 4076 #ifdef __HAVE_CPU_VMSPACE_EXEC 4077 cpu_vmspace_exec(l, start, end); 4078 #endif 4079 4080 map = &ovm->vm_map; 4081 /* 4082 * see if more than one process is using this vmspace... 4083 */ 4084 4085 if (ovm->vm_refcnt == 1 4086 && topdown == ((ovm->vm_map.flags & VM_MAP_TOPDOWN) != 0)) { 4087 4088 /* 4089 * if p is the only process using its vmspace then we can safely 4090 * recycle that vmspace for the program that is being exec'd. 4091 * But only if TOPDOWN matches the requested value for the new 4092 * vm space! 4093 */ 4094 4095 /* 4096 * SYSV SHM semantics require us to kill all segments on an exec 4097 */ 4098 if (uvm_shmexit && ovm->vm_shm) 4099 (*uvm_shmexit)(ovm); 4100 4101 /* 4102 * POSIX 1003.1b -- "lock future mappings" is revoked 4103 * when a process execs another program image. 4104 */ 4105 4106 map->flags &= ~VM_MAP_WIREFUTURE; 4107 4108 /* 4109 * now unmap the old program 4110 */ 4111 4112 pmap_remove_all(map->pmap); 4113 uvm_unmap(map, vm_map_min(map), vm_map_max(map)); 4114 KASSERT(map->header.prev == &map->header); 4115 KASSERT(map->nentries == 0); 4116 4117 /* 4118 * resize the map 4119 */ 4120 4121 vm_map_setmin(map, start); 4122 vm_map_setmax(map, end); 4123 } else { 4124 4125 /* 4126 * p's vmspace is being shared, so we can't reuse it for p since 4127 * it is still being used for others. allocate a new vmspace 4128 * for p 4129 */ 4130 4131 nvm = uvmspace_alloc(start, end, topdown); 4132 4133 /* 4134 * install new vmspace and drop our ref to the old one. 4135 */ 4136 4137 kpreempt_disable(); 4138 pmap_deactivate(l); 4139 p->p_vmspace = nvm; 4140 pmap_activate(l); 4141 kpreempt_enable(); 4142 4143 uvmspace_free(ovm); 4144 } 4145 } 4146 4147 /* 4148 * uvmspace_addref: add a referece to a vmspace. 4149 */ 4150 4151 void 4152 uvmspace_addref(struct vmspace *vm) 4153 { 4154 struct vm_map *map = &vm->vm_map; 4155 4156 KASSERT((map->flags & VM_MAP_DYING) == 0); 4157 4158 mutex_enter(&map->misc_lock); 4159 KASSERT(vm->vm_refcnt > 0); 4160 vm->vm_refcnt++; 4161 mutex_exit(&map->misc_lock); 4162 } 4163 4164 /* 4165 * uvmspace_free: free a vmspace data structure 4166 */ 4167 4168 void 4169 uvmspace_free(struct vmspace *vm) 4170 { 4171 struct vm_map_entry *dead_entries; 4172 struct vm_map *map = &vm->vm_map; 4173 int n; 4174 4175 UVMHIST_FUNC("uvmspace_free"); UVMHIST_CALLED(maphist); 4176 4177 UVMHIST_LOG(maphist,"(vm=%p) ref=%d", vm, vm->vm_refcnt,0,0); 4178 mutex_enter(&map->misc_lock); 4179 n = --vm->vm_refcnt; 4180 mutex_exit(&map->misc_lock); 4181 if (n > 0) 4182 return; 4183 4184 /* 4185 * at this point, there should be no other references to the map. 4186 * delete all of the mappings, then destroy the pmap. 4187 */ 4188 4189 map->flags |= VM_MAP_DYING; 4190 pmap_remove_all(map->pmap); 4191 4192 /* Get rid of any SYSV shared memory segments. */ 4193 if (uvm_shmexit && vm->vm_shm != NULL) 4194 (*uvm_shmexit)(vm); 4195 4196 if (map->nentries) { 4197 uvm_unmap_remove(map, vm_map_min(map), vm_map_max(map), 4198 &dead_entries, 0); 4199 if (dead_entries != NULL) 4200 uvm_unmap_detach(dead_entries, 0); 4201 } 4202 KASSERT(map->nentries == 0); 4203 KASSERT(map->size == 0); 4204 4205 mutex_destroy(&map->misc_lock); 4206 rw_destroy(&map->lock); 4207 cv_destroy(&map->cv); 4208 pmap_destroy(map->pmap); 4209 pool_cache_put(&uvm_vmspace_cache, vm); 4210 } 4211 4212 static struct vm_map_entry * 4213 uvm_mapent_clone(struct vm_map *new_map, struct vm_map_entry *old_entry, 4214 int flags) 4215 { 4216 struct vm_map_entry *new_entry; 4217 4218 new_entry = uvm_mapent_alloc(new_map, 0); 4219 /* old_entry -> new_entry */ 4220 uvm_mapent_copy(old_entry, new_entry); 4221 4222 /* new pmap has nothing wired in it */ 4223 new_entry->wired_count = 0; 4224 4225 /* 4226 * gain reference to object backing the map (can't 4227 * be a submap, already checked this case). 4228 */ 4229 4230 if (new_entry->aref.ar_amap) 4231 uvm_map_reference_amap(new_entry, flags); 4232 4233 if (new_entry->object.uvm_obj && 4234 new_entry->object.uvm_obj->pgops->pgo_reference) 4235 new_entry->object.uvm_obj->pgops->pgo_reference( 4236 new_entry->object.uvm_obj); 4237 4238 /* insert entry at end of new_map's entry list */ 4239 uvm_map_entry_link(new_map, new_map->header.prev, 4240 new_entry); 4241 4242 return new_entry; 4243 } 4244 4245 /* 4246 * share the mapping: this means we want the old and 4247 * new entries to share amaps and backing objects. 4248 */ 4249 static void 4250 uvm_mapent_forkshared(struct vm_map *new_map, struct vm_map *old_map, 4251 struct vm_map_entry *old_entry) 4252 { 4253 /* 4254 * if the old_entry needs a new amap (due to prev fork) 4255 * then we need to allocate it now so that we have 4256 * something we own to share with the new_entry. [in 4257 * other words, we need to clear needs_copy] 4258 */ 4259 4260 if (UVM_ET_ISNEEDSCOPY(old_entry)) { 4261 /* get our own amap, clears needs_copy */ 4262 amap_copy(old_map, old_entry, AMAP_COPY_NOCHUNK, 4263 0, 0); 4264 /* XXXCDC: WAITOK??? */ 4265 } 4266 4267 uvm_mapent_clone(new_map, old_entry, AMAP_SHARED); 4268 } 4269 4270 4271 static void 4272 uvm_mapent_forkcopy(struct vm_map *new_map, struct vm_map *old_map, 4273 struct vm_map_entry *old_entry) 4274 { 4275 struct vm_map_entry *new_entry; 4276 4277 /* 4278 * copy-on-write the mapping (using mmap's 4279 * MAP_PRIVATE semantics) 4280 * 4281 * allocate new_entry, adjust reference counts. 4282 * (note that new references are read-only). 4283 */ 4284 4285 new_entry = uvm_mapent_clone(new_map, old_entry, 0); 4286 4287 new_entry->etype |= 4288 (UVM_ET_COPYONWRITE|UVM_ET_NEEDSCOPY); 4289 4290 /* 4291 * the new entry will need an amap. it will either 4292 * need to be copied from the old entry or created 4293 * from scratch (if the old entry does not have an 4294 * amap). can we defer this process until later 4295 * (by setting "needs_copy") or do we need to copy 4296 * the amap now? 4297 * 4298 * we must copy the amap now if any of the following 4299 * conditions hold: 4300 * 1. the old entry has an amap and that amap is 4301 * being shared. this means that the old (parent) 4302 * process is sharing the amap with another 4303 * process. if we do not clear needs_copy here 4304 * we will end up in a situation where both the 4305 * parent and child process are refering to the 4306 * same amap with "needs_copy" set. if the 4307 * parent write-faults, the fault routine will 4308 * clear "needs_copy" in the parent by allocating 4309 * a new amap. this is wrong because the 4310 * parent is supposed to be sharing the old amap 4311 * and the new amap will break that. 4312 * 4313 * 2. if the old entry has an amap and a non-zero 4314 * wire count then we are going to have to call 4315 * amap_cow_now to avoid page faults in the 4316 * parent process. since amap_cow_now requires 4317 * "needs_copy" to be clear we might as well 4318 * clear it here as well. 4319 * 4320 */ 4321 4322 if (old_entry->aref.ar_amap != NULL) { 4323 if ((amap_flags(old_entry->aref.ar_amap) & AMAP_SHARED) != 0 || 4324 VM_MAPENT_ISWIRED(old_entry)) { 4325 4326 amap_copy(new_map, new_entry, 4327 AMAP_COPY_NOCHUNK, 0, 0); 4328 /* XXXCDC: M_WAITOK ... ok? */ 4329 } 4330 } 4331 4332 /* 4333 * if the parent's entry is wired down, then the 4334 * parent process does not want page faults on 4335 * access to that memory. this means that we 4336 * cannot do copy-on-write because we can't write 4337 * protect the old entry. in this case we 4338 * resolve all copy-on-write faults now, using 4339 * amap_cow_now. note that we have already 4340 * allocated any needed amap (above). 4341 */ 4342 4343 if (VM_MAPENT_ISWIRED(old_entry)) { 4344 4345 /* 4346 * resolve all copy-on-write faults now 4347 * (note that there is nothing to do if 4348 * the old mapping does not have an amap). 4349 */ 4350 if (old_entry->aref.ar_amap) 4351 amap_cow_now(new_map, new_entry); 4352 4353 } else { 4354 /* 4355 * setup mappings to trigger copy-on-write faults 4356 * we must write-protect the parent if it has 4357 * an amap and it is not already "needs_copy"... 4358 * if it is already "needs_copy" then the parent 4359 * has already been write-protected by a previous 4360 * fork operation. 4361 */ 4362 if (old_entry->aref.ar_amap && 4363 !UVM_ET_ISNEEDSCOPY(old_entry)) { 4364 if (old_entry->max_protection & VM_PROT_WRITE) { 4365 pmap_protect(old_map->pmap, 4366 old_entry->start, old_entry->end, 4367 old_entry->protection & ~VM_PROT_WRITE); 4368 } 4369 old_entry->etype |= UVM_ET_NEEDSCOPY; 4370 } 4371 } 4372 } 4373 4374 /* 4375 * zero the mapping: the new entry will be zero initialized 4376 */ 4377 static void 4378 uvm_mapent_forkzero(struct vm_map *new_map, struct vm_map *old_map, 4379 struct vm_map_entry *old_entry) 4380 { 4381 struct vm_map_entry *new_entry; 4382 4383 new_entry = uvm_mapent_clone(new_map, old_entry, 0); 4384 4385 new_entry->etype |= 4386 (UVM_ET_COPYONWRITE|UVM_ET_NEEDSCOPY); 4387 4388 if (new_entry->aref.ar_amap) { 4389 uvm_map_unreference_amap(new_entry, 0); 4390 new_entry->aref.ar_pageoff = 0; 4391 new_entry->aref.ar_amap = NULL; 4392 } 4393 4394 if (UVM_ET_ISOBJ(new_entry)) { 4395 if (new_entry->object.uvm_obj->pgops->pgo_detach) 4396 new_entry->object.uvm_obj->pgops->pgo_detach( 4397 new_entry->object.uvm_obj); 4398 new_entry->object.uvm_obj = NULL; 4399 new_entry->etype &= ~UVM_ET_OBJ; 4400 } 4401 } 4402 4403 /* 4404 * F O R K - m a i n e n t r y p o i n t 4405 */ 4406 /* 4407 * uvmspace_fork: fork a process' main map 4408 * 4409 * => create a new vmspace for child process from parent. 4410 * => parent's map must not be locked. 4411 */ 4412 4413 struct vmspace * 4414 uvmspace_fork(struct vmspace *vm1) 4415 { 4416 struct vmspace *vm2; 4417 struct vm_map *old_map = &vm1->vm_map; 4418 struct vm_map *new_map; 4419 struct vm_map_entry *old_entry; 4420 UVMHIST_FUNC("uvmspace_fork"); UVMHIST_CALLED(maphist); 4421 4422 vm_map_lock(old_map); 4423 4424 vm2 = uvmspace_alloc(vm_map_min(old_map), vm_map_max(old_map), 4425 vm1->vm_map.flags & VM_MAP_TOPDOWN); 4426 memcpy(&vm2->vm_startcopy, &vm1->vm_startcopy, 4427 (char *) (vm1 + 1) - (char *) &vm1->vm_startcopy); 4428 new_map = &vm2->vm_map; /* XXX */ 4429 4430 old_entry = old_map->header.next; 4431 new_map->size = old_map->size; 4432 4433 /* 4434 * go entry-by-entry 4435 */ 4436 4437 while (old_entry != &old_map->header) { 4438 4439 /* 4440 * first, some sanity checks on the old entry 4441 */ 4442 4443 KASSERT(!UVM_ET_ISSUBMAP(old_entry)); 4444 KASSERT(UVM_ET_ISCOPYONWRITE(old_entry) || 4445 !UVM_ET_ISNEEDSCOPY(old_entry)); 4446 4447 switch (old_entry->inheritance) { 4448 case MAP_INHERIT_NONE: 4449 /* 4450 * drop the mapping, modify size 4451 */ 4452 new_map->size -= old_entry->end - old_entry->start; 4453 break; 4454 4455 case MAP_INHERIT_SHARE: 4456 uvm_mapent_forkshared(new_map, old_map, old_entry); 4457 break; 4458 4459 case MAP_INHERIT_COPY: 4460 uvm_mapent_forkcopy(new_map, old_map, old_entry); 4461 break; 4462 4463 case MAP_INHERIT_ZERO: 4464 uvm_mapent_forkzero(new_map, old_map, old_entry); 4465 break; 4466 default: 4467 KASSERT(0); 4468 break; 4469 } 4470 old_entry = old_entry->next; 4471 } 4472 4473 pmap_update(old_map->pmap); 4474 vm_map_unlock(old_map); 4475 4476 if (uvm_shmfork && vm1->vm_shm) 4477 (*uvm_shmfork)(vm1, vm2); 4478 4479 #ifdef PMAP_FORK 4480 pmap_fork(vm1->vm_map.pmap, vm2->vm_map.pmap); 4481 #endif 4482 4483 UVMHIST_LOG(maphist,"<- done",0,0,0,0); 4484 return (vm2); 4485 } 4486 4487 4488 /* 4489 * uvm_mapent_trymerge: try to merge an entry with its neighbors. 4490 * 4491 * => called with map locked. 4492 * => return non zero if successfully merged. 4493 */ 4494 4495 int 4496 uvm_mapent_trymerge(struct vm_map *map, struct vm_map_entry *entry, int flags) 4497 { 4498 struct uvm_object *uobj; 4499 struct vm_map_entry *next; 4500 struct vm_map_entry *prev; 4501 vsize_t size; 4502 int merged = 0; 4503 bool copying; 4504 int newetype; 4505 4506 if (entry->aref.ar_amap != NULL) { 4507 return 0; 4508 } 4509 if ((entry->flags & UVM_MAP_NOMERGE) != 0) { 4510 return 0; 4511 } 4512 4513 uobj = entry->object.uvm_obj; 4514 size = entry->end - entry->start; 4515 copying = (flags & UVM_MERGE_COPYING) != 0; 4516 newetype = copying ? (entry->etype & ~UVM_ET_NEEDSCOPY) : entry->etype; 4517 4518 next = entry->next; 4519 if (next != &map->header && 4520 next->start == entry->end && 4521 ((copying && next->aref.ar_amap != NULL && 4522 amap_refs(next->aref.ar_amap) == 1) || 4523 (!copying && next->aref.ar_amap == NULL)) && 4524 UVM_ET_ISCOMPATIBLE(next, newetype, 4525 uobj, entry->flags, entry->protection, 4526 entry->max_protection, entry->inheritance, entry->advice, 4527 entry->wired_count) && 4528 (uobj == NULL || entry->offset + size == next->offset)) { 4529 int error; 4530 4531 if (copying) { 4532 error = amap_extend(next, size, 4533 AMAP_EXTEND_NOWAIT|AMAP_EXTEND_BACKWARDS); 4534 } else { 4535 error = 0; 4536 } 4537 if (error == 0) { 4538 if (uobj) { 4539 if (uobj->pgops->pgo_detach) { 4540 uobj->pgops->pgo_detach(uobj); 4541 } 4542 } 4543 4544 entry->end = next->end; 4545 clear_hints(map, next); 4546 uvm_map_entry_unlink(map, next); 4547 if (copying) { 4548 entry->aref = next->aref; 4549 entry->etype &= ~UVM_ET_NEEDSCOPY; 4550 } 4551 uvm_map_check(map, "trymerge forwardmerge"); 4552 uvm_mapent_free(next); 4553 merged++; 4554 } 4555 } 4556 4557 prev = entry->prev; 4558 if (prev != &map->header && 4559 prev->end == entry->start && 4560 ((copying && !merged && prev->aref.ar_amap != NULL && 4561 amap_refs(prev->aref.ar_amap) == 1) || 4562 (!copying && prev->aref.ar_amap == NULL)) && 4563 UVM_ET_ISCOMPATIBLE(prev, newetype, 4564 uobj, entry->flags, entry->protection, 4565 entry->max_protection, entry->inheritance, entry->advice, 4566 entry->wired_count) && 4567 (uobj == NULL || 4568 prev->offset + prev->end - prev->start == entry->offset)) { 4569 int error; 4570 4571 if (copying) { 4572 error = amap_extend(prev, size, 4573 AMAP_EXTEND_NOWAIT|AMAP_EXTEND_FORWARDS); 4574 } else { 4575 error = 0; 4576 } 4577 if (error == 0) { 4578 if (uobj) { 4579 if (uobj->pgops->pgo_detach) { 4580 uobj->pgops->pgo_detach(uobj); 4581 } 4582 entry->offset = prev->offset; 4583 } 4584 4585 entry->start = prev->start; 4586 clear_hints(map, prev); 4587 uvm_map_entry_unlink(map, prev); 4588 if (copying) { 4589 entry->aref = prev->aref; 4590 entry->etype &= ~UVM_ET_NEEDSCOPY; 4591 } 4592 uvm_map_check(map, "trymerge backmerge"); 4593 uvm_mapent_free(prev); 4594 merged++; 4595 } 4596 } 4597 4598 return merged; 4599 } 4600 4601 /* 4602 * uvm_map_setup: init map 4603 * 4604 * => map must not be in service yet. 4605 */ 4606 4607 void 4608 uvm_map_setup(struct vm_map *map, vaddr_t vmin, vaddr_t vmax, int flags) 4609 { 4610 4611 rb_tree_init(&map->rb_tree, &uvm_map_tree_ops); 4612 map->header.next = map->header.prev = &map->header; 4613 map->nentries = 0; 4614 map->size = 0; 4615 map->ref_count = 1; 4616 vm_map_setmin(map, vmin); 4617 vm_map_setmax(map, vmax); 4618 map->flags = flags; 4619 map->first_free = &map->header; 4620 map->hint = &map->header; 4621 map->timestamp = 0; 4622 map->busy = NULL; 4623 4624 rw_init(&map->lock); 4625 cv_init(&map->cv, "vm_map"); 4626 mutex_init(&map->misc_lock, MUTEX_DRIVER, IPL_NONE); 4627 } 4628 4629 /* 4630 * U N M A P - m a i n e n t r y p o i n t 4631 */ 4632 4633 /* 4634 * uvm_unmap1: remove mappings from a vm_map (from "start" up to "stop") 4635 * 4636 * => caller must check alignment and size 4637 * => map must be unlocked (we will lock it) 4638 * => flags is UVM_FLAG_QUANTUM or 0. 4639 */ 4640 4641 void 4642 uvm_unmap1(struct vm_map *map, vaddr_t start, vaddr_t end, int flags) 4643 { 4644 struct vm_map_entry *dead_entries; 4645 UVMHIST_FUNC("uvm_unmap"); UVMHIST_CALLED(maphist); 4646 4647 UVMHIST_LOG(maphist, " (map=%p, start=%#lx, end=%#lx)", 4648 map, start, end, 0); 4649 if (map == kernel_map) { 4650 LOCKDEBUG_MEM_CHECK((void *)start, end - start); 4651 } 4652 /* 4653 * work now done by helper functions. wipe the pmap's and then 4654 * detach from the dead entries... 4655 */ 4656 vm_map_lock(map); 4657 uvm_unmap_remove(map, start, end, &dead_entries, flags); 4658 vm_map_unlock(map); 4659 4660 if (dead_entries != NULL) 4661 uvm_unmap_detach(dead_entries, 0); 4662 4663 UVMHIST_LOG(maphist, "<- done", 0,0,0,0); 4664 } 4665 4666 4667 /* 4668 * uvm_map_reference: add reference to a map 4669 * 4670 * => map need not be locked (we use misc_lock). 4671 */ 4672 4673 void 4674 uvm_map_reference(struct vm_map *map) 4675 { 4676 mutex_enter(&map->misc_lock); 4677 map->ref_count++; 4678 mutex_exit(&map->misc_lock); 4679 } 4680 4681 bool 4682 vm_map_starved_p(struct vm_map *map) 4683 { 4684 4685 if ((map->flags & VM_MAP_WANTVA) != 0) { 4686 return true; 4687 } 4688 /* XXX */ 4689 if ((vm_map_max(map) - vm_map_min(map)) / 16 * 15 < map->size) { 4690 return true; 4691 } 4692 return false; 4693 } 4694 4695 void 4696 uvm_map_lock_entry(struct vm_map_entry *entry) 4697 { 4698 4699 if (entry->aref.ar_amap != NULL) { 4700 amap_lock(entry->aref.ar_amap); 4701 } 4702 if (UVM_ET_ISOBJ(entry)) { 4703 mutex_enter(entry->object.uvm_obj->vmobjlock); 4704 } 4705 } 4706 4707 void 4708 uvm_map_unlock_entry(struct vm_map_entry *entry) 4709 { 4710 4711 if (UVM_ET_ISOBJ(entry)) { 4712 mutex_exit(entry->object.uvm_obj->vmobjlock); 4713 } 4714 if (entry->aref.ar_amap != NULL) { 4715 amap_unlock(entry->aref.ar_amap); 4716 } 4717 } 4718 4719 #if defined(DDB) || defined(DEBUGPRINT) 4720 4721 /* 4722 * uvm_map_printit: actually prints the map 4723 */ 4724 4725 void 4726 uvm_map_printit(struct vm_map *map, bool full, 4727 void (*pr)(const char *, ...)) 4728 { 4729 struct vm_map_entry *entry; 4730 4731 (*pr)("MAP %p: [%#lx->%#lx]\n", map, vm_map_min(map), 4732 vm_map_max(map)); 4733 (*pr)("\t#ent=%d, sz=%d, ref=%d, version=%d, flags=%#x\n", 4734 map->nentries, map->size, map->ref_count, map->timestamp, 4735 map->flags); 4736 (*pr)("\tpmap=%p(resident=%ld, wired=%ld)\n", map->pmap, 4737 pmap_resident_count(map->pmap), pmap_wired_count(map->pmap)); 4738 if (!full) 4739 return; 4740 for (entry = map->header.next; entry != &map->header; 4741 entry = entry->next) { 4742 (*pr)(" - %p: %#lx->%#lx: obj=%p/%#llx, amap=%p/%d\n", 4743 entry, entry->start, entry->end, entry->object.uvm_obj, 4744 (long long)entry->offset, entry->aref.ar_amap, 4745 entry->aref.ar_pageoff); 4746 (*pr)( 4747 "\tsubmap=%c, cow=%c, nc=%c, prot(max)=%d/%d, inh=%d, " 4748 "wc=%d, adv=%d\n", 4749 (entry->etype & UVM_ET_SUBMAP) ? 'T' : 'F', 4750 (entry->etype & UVM_ET_COPYONWRITE) ? 'T' : 'F', 4751 (entry->etype & UVM_ET_NEEDSCOPY) ? 'T' : 'F', 4752 entry->protection, entry->max_protection, 4753 entry->inheritance, entry->wired_count, entry->advice); 4754 } 4755 } 4756 4757 void 4758 uvm_whatis(uintptr_t addr, void (*pr)(const char *, ...)) 4759 { 4760 struct vm_map *map; 4761 4762 for (map = kernel_map;;) { 4763 struct vm_map_entry *entry; 4764 4765 if (!uvm_map_lookup_entry_bytree(map, (vaddr_t)addr, &entry)) { 4766 break; 4767 } 4768 (*pr)("%p is %p+%zu from VMMAP %p\n", 4769 (void *)addr, (void *)entry->start, 4770 (size_t)(addr - (uintptr_t)entry->start), map); 4771 if (!UVM_ET_ISSUBMAP(entry)) { 4772 break; 4773 } 4774 map = entry->object.sub_map; 4775 } 4776 } 4777 4778 #endif /* DDB || DEBUGPRINT */ 4779 4780 #ifndef __USER_VA0_IS_SAFE 4781 static int 4782 sysctl_user_va0_disable(SYSCTLFN_ARGS) 4783 { 4784 struct sysctlnode node; 4785 int t, error; 4786 4787 node = *rnode; 4788 node.sysctl_data = &t; 4789 t = user_va0_disable; 4790 error = sysctl_lookup(SYSCTLFN_CALL(&node)); 4791 if (error || newp == NULL) 4792 return (error); 4793 4794 if (!t && user_va0_disable && 4795 kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_MAP_VA_ZERO, 0, 4796 NULL, NULL, NULL)) 4797 return EPERM; 4798 4799 user_va0_disable = !!t; 4800 return 0; 4801 } 4802 #endif 4803 4804 static int 4805 fill_vmentry(struct lwp *l, struct proc *p, struct kinfo_vmentry *kve, 4806 struct vm_map *m, struct vm_map_entry *e) 4807 { 4808 #ifndef _RUMPKERNEL 4809 int error; 4810 4811 memset(kve, 0, sizeof(*kve)); 4812 KASSERT(e != NULL); 4813 if (UVM_ET_ISOBJ(e)) { 4814 struct uvm_object *uobj = e->object.uvm_obj; 4815 KASSERT(uobj != NULL); 4816 kve->kve_ref_count = uobj->uo_refs; 4817 kve->kve_count = uobj->uo_npages; 4818 if (UVM_OBJ_IS_VNODE(uobj)) { 4819 struct vattr va; 4820 struct vnode *vp = (struct vnode *)uobj; 4821 vn_lock(vp, LK_SHARED | LK_RETRY); 4822 error = VOP_GETATTR(vp, &va, l->l_cred); 4823 VOP_UNLOCK(vp); 4824 kve->kve_type = KVME_TYPE_VNODE; 4825 if (error == 0) { 4826 kve->kve_vn_size = vp->v_size; 4827 kve->kve_vn_type = (int)vp->v_type; 4828 kve->kve_vn_mode = va.va_mode; 4829 kve->kve_vn_rdev = va.va_rdev; 4830 kve->kve_vn_fileid = va.va_fileid; 4831 kve->kve_vn_fsid = va.va_fsid; 4832 error = vnode_to_path(kve->kve_path, 4833 sizeof(kve->kve_path) / 2, vp, l, p); 4834 #ifdef DIAGNOSTIC 4835 if (error) 4836 printf("%s: vp %p error %d\n", __func__, 4837 vp, error); 4838 #endif 4839 } 4840 } else if (UVM_OBJ_IS_KERN_OBJECT(uobj)) { 4841 kve->kve_type = KVME_TYPE_KERN; 4842 } else if (UVM_OBJ_IS_DEVICE(uobj)) { 4843 kve->kve_type = KVME_TYPE_DEVICE; 4844 } else if (UVM_OBJ_IS_AOBJ(uobj)) { 4845 kve->kve_type = KVME_TYPE_ANON; 4846 } else { 4847 kve->kve_type = KVME_TYPE_OBJECT; 4848 } 4849 } else if (UVM_ET_ISSUBMAP(e)) { 4850 struct vm_map *map = e->object.sub_map; 4851 KASSERT(map != NULL); 4852 kve->kve_ref_count = map->ref_count; 4853 kve->kve_count = map->nentries; 4854 kve->kve_type = KVME_TYPE_SUBMAP; 4855 } else 4856 kve->kve_type = KVME_TYPE_UNKNOWN; 4857 4858 kve->kve_start = e->start; 4859 kve->kve_end = e->end; 4860 kve->kve_offset = e->offset; 4861 kve->kve_wired_count = e->wired_count; 4862 kve->kve_inheritance = e->inheritance; 4863 kve->kve_attributes = e->map_attrib; 4864 kve->kve_advice = e->advice; 4865 #define PROT(p) (((p) & VM_PROT_READ) ? KVME_PROT_READ : 0) | \ 4866 (((p) & VM_PROT_WRITE) ? KVME_PROT_WRITE : 0) | \ 4867 (((p) & VM_PROT_EXECUTE) ? KVME_PROT_EXEC : 0) 4868 kve->kve_protection = PROT(e->protection); 4869 kve->kve_max_protection = PROT(e->max_protection); 4870 kve->kve_flags |= (e->etype & UVM_ET_COPYONWRITE) 4871 ? KVME_FLAG_COW : 0; 4872 kve->kve_flags |= (e->etype & UVM_ET_NEEDSCOPY) 4873 ? KVME_FLAG_NEEDS_COPY : 0; 4874 kve->kve_flags |= (m->flags & VM_MAP_TOPDOWN) 4875 ? KVME_FLAG_GROWS_DOWN : KVME_FLAG_GROWS_UP; 4876 kve->kve_flags |= (m->flags & VM_MAP_PAGEABLE) 4877 ? KVME_FLAG_PAGEABLE : 0; 4878 #endif 4879 return 0; 4880 } 4881 4882 static int 4883 fill_vmentries(struct lwp *l, pid_t pid, u_int elem_size, void *oldp, 4884 size_t *oldlenp) 4885 { 4886 int error; 4887 struct proc *p; 4888 struct kinfo_vmentry *vme; 4889 struct vmspace *vm; 4890 struct vm_map *map; 4891 struct vm_map_entry *entry; 4892 char *dp; 4893 size_t count, vmesize; 4894 4895 vme = NULL; 4896 vmesize = *oldlenp; 4897 count = 0; 4898 if (oldp && *oldlenp > 1024 * 1024) 4899 return E2BIG; 4900 4901 if ((error = proc_find_locked(l, &p, pid)) != 0) 4902 return error; 4903 4904 if ((error = proc_vmspace_getref(p, &vm)) != 0) 4905 goto out; 4906 4907 map = &vm->vm_map; 4908 vm_map_lock_read(map); 4909 4910 dp = oldp; 4911 if (oldp) 4912 vme = kmem_alloc(vmesize, KM_SLEEP); 4913 for (entry = map->header.next; entry != &map->header; 4914 entry = entry->next) { 4915 if (oldp && (dp - (char *)oldp) < *oldlenp + elem_size) { 4916 error = fill_vmentry(l, p, &vme[count], map, entry); 4917 if (error) 4918 goto out; 4919 dp += elem_size; 4920 } 4921 count++; 4922 } 4923 vm_map_unlock_read(map); 4924 uvmspace_free(vm); 4925 4926 out: 4927 if (pid != -1) 4928 mutex_exit(p->p_lock); 4929 if (error == 0) { 4930 const u_int esize = min(sizeof(*vme), elem_size); 4931 dp = oldp; 4932 for (size_t i = 0; i < count; i++) { 4933 if (oldp && (dp - (char *)oldp) < *oldlenp + elem_size) 4934 { 4935 error = sysctl_copyout(l, &vme[i], dp, esize); 4936 if (error) 4937 break; 4938 dp += elem_size; 4939 } else 4940 break; 4941 } 4942 count *= elem_size; 4943 if (oldp != NULL && *oldlenp < count) 4944 error = ENOSPC; 4945 *oldlenp = count; 4946 } 4947 if (vme) 4948 kmem_free(vme, vmesize); 4949 return error; 4950 } 4951 4952 static int 4953 sysctl_vmproc(SYSCTLFN_ARGS) 4954 { 4955 int error; 4956 4957 if (namelen == 1 && name[0] == CTL_QUERY) 4958 return (sysctl_query(SYSCTLFN_CALL(rnode))); 4959 4960 if (namelen == 0) 4961 return EINVAL; 4962 4963 switch (name[0]) { 4964 case VM_PROC_MAP: 4965 if (namelen != 3) 4966 return EINVAL; 4967 sysctl_unlock(); 4968 error = fill_vmentries(l, name[1], name[2], 4969 oldp, oldlenp); 4970 sysctl_relock(); 4971 return error; 4972 default: 4973 return EINVAL; 4974 } 4975 } 4976 4977 SYSCTL_SETUP(sysctl_uvmmap_setup, "sysctl uvmmap setup") 4978 { 4979 4980 sysctl_createv(clog, 0, NULL, NULL, 4981 CTLFLAG_PERMANENT, 4982 CTLTYPE_STRUCT, "proc", 4983 SYSCTL_DESCR("Process vm information"), 4984 sysctl_vmproc, 0, NULL, 0, 4985 CTL_VM, VM_PROC, CTL_EOL); 4986 #ifndef __USER_VA0_IS_SAFE 4987 sysctl_createv(clog, 0, NULL, NULL, 4988 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 4989 CTLTYPE_INT, "user_va0_disable", 4990 SYSCTL_DESCR("Disable VA 0"), 4991 sysctl_user_va0_disable, 0, &user_va0_disable, 0, 4992 CTL_VM, CTL_CREATE, CTL_EOL); 4993 #endif 4994 } 4995