1 /* $NetBSD: uvm_map.c,v 1.215 2006/03/01 12:38:44 yamt 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. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by Charles D. Cranor, 23 * Washington University, the University of California, Berkeley and 24 * its contributors. 25 * 4. Neither the name of the University nor the names of its contributors 26 * may be used to endorse or promote products derived from this software 27 * without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 39 * SUCH DAMAGE. 40 * 41 * @(#)vm_map.c 8.3 (Berkeley) 1/12/94 42 * from: Id: uvm_map.c,v 1.1.2.27 1998/02/07 01:16:54 chs Exp 43 * 44 * 45 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 46 * All rights reserved. 47 * 48 * Permission to use, copy, modify and distribute this software and 49 * its documentation is hereby granted, provided that both the copyright 50 * notice and this permission notice appear in all copies of the 51 * software, derivative works or modified versions, and any portions 52 * thereof, and that both notices appear in supporting documentation. 53 * 54 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 55 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 56 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 57 * 58 * Carnegie Mellon requests users of this software to return to 59 * 60 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 61 * School of Computer Science 62 * Carnegie Mellon University 63 * Pittsburgh PA 15213-3890 64 * 65 * any improvements or extensions that they make and grant Carnegie the 66 * rights to redistribute these changes. 67 */ 68 69 /* 70 * uvm_map.c: uvm map operations 71 */ 72 73 #include <sys/cdefs.h> 74 __KERNEL_RCSID(0, "$NetBSD: uvm_map.c,v 1.215 2006/03/01 12:38:44 yamt Exp $"); 75 76 #include "opt_ddb.h" 77 #include "opt_uvmhist.h" 78 #include "opt_uvm.h" 79 #include "opt_sysv.h" 80 81 #include <sys/param.h> 82 #include <sys/systm.h> 83 #include <sys/mman.h> 84 #include <sys/proc.h> 85 #include <sys/malloc.h> 86 #include <sys/pool.h> 87 #include <sys/kernel.h> 88 #include <sys/mount.h> 89 #include <sys/vnode.h> 90 91 #ifdef SYSVSHM 92 #include <sys/shm.h> 93 #endif 94 95 #include <uvm/uvm.h> 96 #undef RB_AUGMENT 97 #define RB_AUGMENT(x) uvm_rb_augment(x) 98 99 #ifdef DDB 100 #include <uvm/uvm_ddb.h> 101 #endif 102 103 #if defined(UVMMAP_NOCOUNTERS) 104 105 #define UVMMAP_EVCNT_DEFINE(name) /* nothing */ 106 #define UVMMAP_EVCNT_INCR(ev) /* nothing */ 107 #define UVMMAP_EVCNT_DECR(ev) /* nothing */ 108 109 #else /* defined(UVMMAP_NOCOUNTERS) */ 110 111 #include <sys/device.h> 112 #define UVMMAP_EVCNT_DEFINE(name) \ 113 struct evcnt uvmmap_evcnt_##name = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, \ 114 "uvmmap", #name); \ 115 EVCNT_ATTACH_STATIC(uvmmap_evcnt_##name); 116 #define UVMMAP_EVCNT_INCR(ev) uvmmap_evcnt_##ev.ev_count++ 117 #define UVMMAP_EVCNT_DECR(ev) uvmmap_evcnt_##ev.ev_count-- 118 119 #endif /* defined(UVMMAP_NOCOUNTERS) */ 120 121 UVMMAP_EVCNT_DEFINE(ubackmerge) 122 UVMMAP_EVCNT_DEFINE(uforwmerge) 123 UVMMAP_EVCNT_DEFINE(ubimerge) 124 UVMMAP_EVCNT_DEFINE(unomerge) 125 UVMMAP_EVCNT_DEFINE(kbackmerge) 126 UVMMAP_EVCNT_DEFINE(kforwmerge) 127 UVMMAP_EVCNT_DEFINE(kbimerge) 128 UVMMAP_EVCNT_DEFINE(knomerge) 129 UVMMAP_EVCNT_DEFINE(map_call) 130 UVMMAP_EVCNT_DEFINE(mlk_call) 131 UVMMAP_EVCNT_DEFINE(mlk_hint) 132 133 UVMMAP_EVCNT_DEFINE(uke_alloc) 134 UVMMAP_EVCNT_DEFINE(uke_free) 135 UVMMAP_EVCNT_DEFINE(ukh_alloc) 136 UVMMAP_EVCNT_DEFINE(ukh_free) 137 138 const char vmmapbsy[] = "vmmapbsy"; 139 140 /* 141 * pool for vmspace structures. 142 */ 143 144 POOL_INIT(uvm_vmspace_pool, sizeof(struct vmspace), 0, 0, 0, "vmsppl", 145 &pool_allocator_nointr); 146 147 /* 148 * pool for dynamically-allocated map entries. 149 */ 150 151 POOL_INIT(uvm_map_entry_pool, sizeof(struct vm_map_entry), 0, 0, 0, "vmmpepl", 152 &pool_allocator_nointr); 153 154 MALLOC_DEFINE(M_VMMAP, "VM map", "VM map structures"); 155 MALLOC_DEFINE(M_VMPMAP, "VM pmap", "VM pmap"); 156 157 #ifdef PMAP_GROWKERNEL 158 /* 159 * This global represents the end of the kernel virtual address 160 * space. If we want to exceed this, we must grow the kernel 161 * virtual address space dynamically. 162 * 163 * Note, this variable is locked by kernel_map's lock. 164 */ 165 vaddr_t uvm_maxkaddr; 166 #endif 167 168 /* 169 * macros 170 */ 171 172 /* 173 * VM_MAP_USE_KMAPENT: determine if uvm_kmapent_alloc/free is used 174 * for the vm_map. 175 */ 176 extern struct vm_map *pager_map; /* XXX */ 177 #define VM_MAP_USE_KMAPENT(map) \ 178 (((map)->flags & VM_MAP_INTRSAFE) || (map) == kernel_map) 179 180 /* 181 * UVM_ET_ISCOMPATIBLE: check some requirements for map entry merging 182 */ 183 184 #define UVM_ET_ISCOMPATIBLE(ent, type, uobj, meflags, \ 185 prot, maxprot, inh, adv, wire) \ 186 ((ent)->etype == (type) && \ 187 (((ent)->flags ^ (meflags)) & (UVM_MAP_NOMERGE | UVM_MAP_QUANTUM)) \ 188 == 0 && \ 189 (ent)->object.uvm_obj == (uobj) && \ 190 (ent)->protection == (prot) && \ 191 (ent)->max_protection == (maxprot) && \ 192 (ent)->inheritance == (inh) && \ 193 (ent)->advice == (adv) && \ 194 (ent)->wired_count == (wire)) 195 196 /* 197 * uvm_map_entry_link: insert entry into a map 198 * 199 * => map must be locked 200 */ 201 #define uvm_map_entry_link(map, after_where, entry) do { \ 202 KASSERT(entry->start < entry->end); \ 203 (map)->nentries++; \ 204 (entry)->prev = (after_where); \ 205 (entry)->next = (after_where)->next; \ 206 (entry)->prev->next = (entry); \ 207 (entry)->next->prev = (entry); \ 208 uvm_rb_insert((map), (entry)); \ 209 } while (/*CONSTCOND*/ 0) 210 211 /* 212 * uvm_map_entry_unlink: remove entry from a map 213 * 214 * => map must be locked 215 */ 216 #define uvm_map_entry_unlink(map, entry) do { \ 217 (map)->nentries--; \ 218 (entry)->next->prev = (entry)->prev; \ 219 (entry)->prev->next = (entry)->next; \ 220 uvm_rb_remove((map), (entry)); \ 221 } while (/*CONSTCOND*/ 0) 222 223 /* 224 * SAVE_HINT: saves the specified entry as the hint for future lookups. 225 * 226 * => map need not be locked (protected by hint_lock). 227 */ 228 #define SAVE_HINT(map,check,value) do { \ 229 simple_lock(&(map)->hint_lock); \ 230 if ((map)->hint == (check)) \ 231 (map)->hint = (value); \ 232 simple_unlock(&(map)->hint_lock); \ 233 } while (/*CONSTCOND*/ 0) 234 235 /* 236 * VM_MAP_RANGE_CHECK: check and correct range 237 * 238 * => map must at least be read locked 239 */ 240 241 #define VM_MAP_RANGE_CHECK(map, start, end) do { \ 242 if (start < vm_map_min(map)) \ 243 start = vm_map_min(map); \ 244 if (end > vm_map_max(map)) \ 245 end = vm_map_max(map); \ 246 if (start > end) \ 247 start = end; \ 248 } while (/*CONSTCOND*/ 0) 249 250 /* 251 * local prototypes 252 */ 253 254 static struct vm_map_entry * 255 uvm_mapent_alloc(struct vm_map *, int); 256 static struct vm_map_entry * 257 uvm_mapent_alloc_split(struct vm_map *, 258 const struct vm_map_entry *, int, 259 struct uvm_mapent_reservation *); 260 static void uvm_mapent_copy(struct vm_map_entry *, struct vm_map_entry *); 261 static void uvm_mapent_free(struct vm_map_entry *); 262 static struct vm_map_entry * 263 uvm_kmapent_alloc(struct vm_map *, int); 264 static void uvm_kmapent_free(struct vm_map_entry *); 265 static void uvm_map_entry_unwire(struct vm_map *, struct vm_map_entry *); 266 static void uvm_map_reference_amap(struct vm_map_entry *, int); 267 static int uvm_map_space_avail(vaddr_t *, vsize_t, voff_t, vsize_t, int, 268 struct vm_map_entry *); 269 static void uvm_map_unreference_amap(struct vm_map_entry *, int); 270 271 int _uvm_tree_sanity(struct vm_map *, const char *); 272 static vsize_t uvm_rb_subtree_space(const struct vm_map_entry *); 273 274 static inline int 275 uvm_compare(const struct vm_map_entry *a, const struct vm_map_entry *b) 276 { 277 278 if (a->start < b->start) 279 return (-1); 280 else if (a->start > b->start) 281 return (1); 282 283 return (0); 284 } 285 286 static inline void 287 uvm_rb_augment(struct vm_map_entry *entry) 288 { 289 290 entry->space = uvm_rb_subtree_space(entry); 291 } 292 293 RB_PROTOTYPE(uvm_tree, vm_map_entry, rb_entry, uvm_compare); 294 295 RB_GENERATE(uvm_tree, vm_map_entry, rb_entry, uvm_compare); 296 297 static inline vsize_t 298 uvm_rb_space(const struct vm_map *map, const struct vm_map_entry *entry) 299 { 300 /* XXX map is not used */ 301 302 KASSERT(entry->next != NULL); 303 return entry->next->start - entry->end; 304 } 305 306 static vsize_t 307 uvm_rb_subtree_space(const struct vm_map_entry *entry) 308 { 309 vaddr_t space, tmp; 310 311 space = entry->ownspace; 312 if (RB_LEFT(entry, rb_entry)) { 313 tmp = RB_LEFT(entry, rb_entry)->space; 314 if (tmp > space) 315 space = tmp; 316 } 317 318 if (RB_RIGHT(entry, rb_entry)) { 319 tmp = RB_RIGHT(entry, rb_entry)->space; 320 if (tmp > space) 321 space = tmp; 322 } 323 324 return (space); 325 } 326 327 static inline void 328 uvm_rb_fixup(struct vm_map *map, struct vm_map_entry *entry) 329 { 330 /* We need to traverse to the very top */ 331 do { 332 entry->ownspace = uvm_rb_space(map, entry); 333 entry->space = uvm_rb_subtree_space(entry); 334 } while ((entry = RB_PARENT(entry, rb_entry)) != NULL); 335 } 336 337 static void 338 uvm_rb_insert(struct vm_map *map, struct vm_map_entry *entry) 339 { 340 vaddr_t space = uvm_rb_space(map, entry); 341 struct vm_map_entry *tmp; 342 343 entry->ownspace = entry->space = space; 344 tmp = RB_INSERT(uvm_tree, &(map)->rbhead, entry); 345 #ifdef DIAGNOSTIC 346 if (tmp != NULL) 347 panic("uvm_rb_insert: duplicate entry?"); 348 #endif 349 uvm_rb_fixup(map, entry); 350 if (entry->prev != &map->header) 351 uvm_rb_fixup(map, entry->prev); 352 } 353 354 static void 355 uvm_rb_remove(struct vm_map *map, struct vm_map_entry *entry) 356 { 357 struct vm_map_entry *parent; 358 359 parent = RB_PARENT(entry, rb_entry); 360 RB_REMOVE(uvm_tree, &(map)->rbhead, entry); 361 if (entry->prev != &map->header) 362 uvm_rb_fixup(map, entry->prev); 363 if (parent) 364 uvm_rb_fixup(map, parent); 365 } 366 367 #ifdef DEBUG 368 int uvm_debug_check_rbtree = 0; 369 #define uvm_tree_sanity(x,y) \ 370 if (uvm_debug_check_rbtree) \ 371 _uvm_tree_sanity(x,y) 372 #else 373 #define uvm_tree_sanity(x,y) 374 #endif 375 376 int 377 _uvm_tree_sanity(struct vm_map *map, const char *name) 378 { 379 struct vm_map_entry *tmp, *trtmp; 380 int n = 0, i = 1; 381 382 RB_FOREACH(tmp, uvm_tree, &map->rbhead) { 383 if (tmp->ownspace != uvm_rb_space(map, tmp)) { 384 printf("%s: %d/%d ownspace %lx != %lx %s\n", 385 name, n + 1, map->nentries, 386 (ulong)tmp->ownspace, (ulong)uvm_rb_space(map, tmp), 387 tmp->next == &map->header ? "(last)" : ""); 388 goto error; 389 } 390 } 391 trtmp = NULL; 392 RB_FOREACH(tmp, uvm_tree, &map->rbhead) { 393 if (tmp->space != uvm_rb_subtree_space(tmp)) { 394 printf("%s: space %lx != %lx\n", 395 name, (ulong)tmp->space, 396 (ulong)uvm_rb_subtree_space(tmp)); 397 goto error; 398 } 399 if (trtmp != NULL && trtmp->start >= tmp->start) { 400 printf("%s: corrupt: 0x%lx >= 0x%lx\n", 401 name, trtmp->start, tmp->start); 402 goto error; 403 } 404 n++; 405 406 trtmp = tmp; 407 } 408 409 if (n != map->nentries) { 410 printf("%s: nentries: %d vs %d\n", 411 name, n, map->nentries); 412 goto error; 413 } 414 415 for (tmp = map->header.next; tmp && tmp != &map->header; 416 tmp = tmp->next, i++) { 417 trtmp = RB_FIND(uvm_tree, &map->rbhead, tmp); 418 if (trtmp != tmp) { 419 printf("%s: lookup: %d: %p - %p: %p\n", 420 name, i, tmp, trtmp, 421 RB_PARENT(tmp, rb_entry)); 422 goto error; 423 } 424 } 425 426 return (0); 427 error: 428 #if defined(DDB) && __GNUC__ < 4 429 /* handy breakpoint location for error case */ 430 __asm(".globl treesanity_label\ntreesanity_label:"); 431 #endif 432 return (-1); 433 } 434 435 #ifdef DIAGNOSTIC 436 static struct vm_map *uvm_kmapent_map(struct vm_map_entry *); 437 #endif 438 439 /* 440 * uvm_mapent_alloc: allocate a map entry 441 */ 442 443 static struct vm_map_entry * 444 uvm_mapent_alloc(struct vm_map *map, int flags) 445 { 446 struct vm_map_entry *me; 447 int pflags = (flags & UVM_FLAG_NOWAIT) ? PR_NOWAIT : PR_WAITOK; 448 UVMHIST_FUNC("uvm_mapent_alloc"); UVMHIST_CALLED(maphist); 449 450 if (VM_MAP_USE_KMAPENT(map)) { 451 me = uvm_kmapent_alloc(map, flags); 452 } else { 453 me = pool_get(&uvm_map_entry_pool, pflags); 454 if (__predict_false(me == NULL)) 455 return NULL; 456 me->flags = 0; 457 } 458 459 UVMHIST_LOG(maphist, "<- new entry=0x%x [kentry=%d]", me, 460 ((map->flags & VM_MAP_INTRSAFE) != 0 || map == kernel_map), 0, 0); 461 return (me); 462 } 463 464 /* 465 * uvm_mapent_alloc_split: allocate a map entry for clipping. 466 */ 467 468 static struct vm_map_entry * 469 uvm_mapent_alloc_split(struct vm_map *map, 470 const struct vm_map_entry *old_entry, int flags, 471 struct uvm_mapent_reservation *umr) 472 { 473 struct vm_map_entry *me; 474 475 KASSERT(!VM_MAP_USE_KMAPENT(map) || 476 (old_entry->flags & UVM_MAP_QUANTUM) || !UMR_EMPTY(umr)); 477 478 if (old_entry->flags & UVM_MAP_QUANTUM) { 479 int s; 480 struct vm_map_kernel *vmk = vm_map_to_kernel(map); 481 482 s = splvm(); 483 simple_lock(&uvm.kentry_lock); 484 me = vmk->vmk_merged_entries; 485 KASSERT(me); 486 vmk->vmk_merged_entries = me->next; 487 simple_unlock(&uvm.kentry_lock); 488 splx(s); 489 KASSERT(me->flags & UVM_MAP_QUANTUM); 490 } else { 491 me = uvm_mapent_alloc(map, flags); 492 } 493 494 return me; 495 } 496 497 /* 498 * uvm_mapent_free: free map entry 499 */ 500 501 static void 502 uvm_mapent_free(struct vm_map_entry *me) 503 { 504 UVMHIST_FUNC("uvm_mapent_free"); UVMHIST_CALLED(maphist); 505 506 UVMHIST_LOG(maphist,"<- freeing map entry=0x%x [flags=%d]", 507 me, me->flags, 0, 0); 508 if (me->flags & UVM_MAP_KERNEL) { 509 uvm_kmapent_free(me); 510 } else { 511 pool_put(&uvm_map_entry_pool, me); 512 } 513 } 514 515 /* 516 * uvm_mapent_free_merged: free merged map entry 517 * 518 * => keep the entry if needed. 519 * => caller shouldn't hold map locked if VM_MAP_USE_KMAPENT(map) is true. 520 */ 521 522 static void 523 uvm_mapent_free_merged(struct vm_map *map, struct vm_map_entry *me) 524 { 525 526 KASSERT(!(me->flags & UVM_MAP_KERNEL) || uvm_kmapent_map(me) == map); 527 528 if (me->flags & UVM_MAP_QUANTUM) { 529 /* 530 * keep this entry for later splitting. 531 */ 532 struct vm_map_kernel *vmk; 533 int s; 534 535 KASSERT(VM_MAP_IS_KERNEL(map)); 536 KASSERT(!VM_MAP_USE_KMAPENT(map) || 537 (me->flags & UVM_MAP_KERNEL)); 538 539 vmk = vm_map_to_kernel(map); 540 s = splvm(); 541 simple_lock(&uvm.kentry_lock); 542 me->next = vmk->vmk_merged_entries; 543 vmk->vmk_merged_entries = me; 544 simple_unlock(&uvm.kentry_lock); 545 splx(s); 546 } else { 547 uvm_mapent_free(me); 548 } 549 } 550 551 /* 552 * uvm_mapent_copy: copy a map entry, preserving flags 553 */ 554 555 static inline void 556 uvm_mapent_copy(struct vm_map_entry *src, struct vm_map_entry *dst) 557 { 558 559 memcpy(dst, src, ((char *)&src->uvm_map_entry_stop_copy) - 560 ((char *)src)); 561 } 562 563 /* 564 * uvm_map_entry_unwire: unwire a map entry 565 * 566 * => map should be locked by caller 567 */ 568 569 static inline void 570 uvm_map_entry_unwire(struct vm_map *map, struct vm_map_entry *entry) 571 { 572 573 entry->wired_count = 0; 574 uvm_fault_unwire_locked(map, entry->start, entry->end); 575 } 576 577 578 /* 579 * wrapper for calling amap_ref() 580 */ 581 static inline void 582 uvm_map_reference_amap(struct vm_map_entry *entry, int flags) 583 { 584 585 amap_ref(entry->aref.ar_amap, entry->aref.ar_pageoff, 586 (entry->end - entry->start) >> PAGE_SHIFT, flags); 587 } 588 589 590 /* 591 * wrapper for calling amap_unref() 592 */ 593 static inline void 594 uvm_map_unreference_amap(struct vm_map_entry *entry, int flags) 595 { 596 597 amap_unref(entry->aref.ar_amap, entry->aref.ar_pageoff, 598 (entry->end - entry->start) >> PAGE_SHIFT, flags); 599 } 600 601 602 /* 603 * uvm_map_init: init mapping system at boot time. note that we allocate 604 * and init the static pool of struct vm_map_entry *'s for the kernel here. 605 */ 606 607 void 608 uvm_map_init(void) 609 { 610 #if defined(UVMHIST) 611 static struct uvm_history_ent maphistbuf[100]; 612 static struct uvm_history_ent pdhistbuf[100]; 613 #endif 614 615 /* 616 * first, init logging system. 617 */ 618 619 UVMHIST_FUNC("uvm_map_init"); 620 UVMHIST_INIT_STATIC(maphist, maphistbuf); 621 UVMHIST_INIT_STATIC(pdhist, pdhistbuf); 622 UVMHIST_CALLED(maphist); 623 UVMHIST_LOG(maphist,"<starting uvm map system>", 0, 0, 0, 0); 624 625 /* 626 * initialize the global lock for kernel map entry. 627 * 628 * XXX is it worth to have per-map lock instead? 629 */ 630 631 simple_lock_init(&uvm.kentry_lock); 632 } 633 634 /* 635 * clippers 636 */ 637 638 /* 639 * uvm_map_clip_start: ensure that the entry begins at or after 640 * the starting address, if it doesn't we split the entry. 641 * 642 * => caller should use UVM_MAP_CLIP_START macro rather than calling 643 * this directly 644 * => map must be locked by caller 645 */ 646 647 void 648 uvm_map_clip_start(struct vm_map *map, struct vm_map_entry *entry, 649 vaddr_t start, struct uvm_mapent_reservation *umr) 650 { 651 struct vm_map_entry *new_entry; 652 vaddr_t new_adj; 653 654 /* uvm_map_simplify_entry(map, entry); */ /* XXX */ 655 656 uvm_tree_sanity(map, "clip_start entry"); 657 658 /* 659 * Split off the front portion. note that we must insert the new 660 * entry BEFORE this one, so that this entry has the specified 661 * starting address. 662 */ 663 new_entry = uvm_mapent_alloc_split(map, entry, 0, umr); 664 uvm_mapent_copy(entry, new_entry); /* entry -> new_entry */ 665 666 new_entry->end = start; 667 new_adj = start - new_entry->start; 668 if (entry->object.uvm_obj) 669 entry->offset += new_adj; /* shift start over */ 670 671 /* Does not change order for the RB tree */ 672 entry->start = start; 673 674 if (new_entry->aref.ar_amap) { 675 amap_splitref(&new_entry->aref, &entry->aref, new_adj); 676 } 677 678 uvm_map_entry_link(map, entry->prev, new_entry); 679 680 if (UVM_ET_ISSUBMAP(entry)) { 681 /* ... unlikely to happen, but play it safe */ 682 uvm_map_reference(new_entry->object.sub_map); 683 } else { 684 if (UVM_ET_ISOBJ(entry) && 685 entry->object.uvm_obj->pgops && 686 entry->object.uvm_obj->pgops->pgo_reference) 687 entry->object.uvm_obj->pgops->pgo_reference( 688 entry->object.uvm_obj); 689 } 690 691 uvm_tree_sanity(map, "clip_start leave"); 692 } 693 694 /* 695 * uvm_map_clip_end: ensure that the entry ends at or before 696 * the ending address, if it does't we split the reference 697 * 698 * => caller should use UVM_MAP_CLIP_END macro rather than calling 699 * this directly 700 * => map must be locked by caller 701 */ 702 703 void 704 uvm_map_clip_end(struct vm_map *map, struct vm_map_entry *entry, vaddr_t end, 705 struct uvm_mapent_reservation *umr) 706 { 707 struct vm_map_entry * new_entry; 708 vaddr_t new_adj; /* #bytes we move start forward */ 709 710 uvm_tree_sanity(map, "clip_end entry"); 711 712 /* 713 * Create a new entry and insert it 714 * AFTER the specified entry 715 */ 716 new_entry = uvm_mapent_alloc_split(map, entry, 0, umr); 717 uvm_mapent_copy(entry, new_entry); /* entry -> new_entry */ 718 719 new_entry->start = entry->end = end; 720 new_adj = end - entry->start; 721 if (new_entry->object.uvm_obj) 722 new_entry->offset += new_adj; 723 724 if (entry->aref.ar_amap) 725 amap_splitref(&entry->aref, &new_entry->aref, new_adj); 726 727 uvm_rb_fixup(map, entry); 728 729 uvm_map_entry_link(map, entry, new_entry); 730 731 if (UVM_ET_ISSUBMAP(entry)) { 732 /* ... unlikely to happen, but play it safe */ 733 uvm_map_reference(new_entry->object.sub_map); 734 } else { 735 if (UVM_ET_ISOBJ(entry) && 736 entry->object.uvm_obj->pgops && 737 entry->object.uvm_obj->pgops->pgo_reference) 738 entry->object.uvm_obj->pgops->pgo_reference( 739 entry->object.uvm_obj); 740 } 741 742 uvm_tree_sanity(map, "clip_end leave"); 743 } 744 745 746 /* 747 * M A P - m a i n e n t r y p o i n t 748 */ 749 /* 750 * uvm_map: establish a valid mapping in a map 751 * 752 * => assume startp is page aligned. 753 * => assume size is a multiple of PAGE_SIZE. 754 * => assume sys_mmap provides enough of a "hint" to have us skip 755 * over text/data/bss area. 756 * => map must be unlocked (we will lock it) 757 * => <uobj,uoffset> value meanings (4 cases): 758 * [1] <NULL,uoffset> == uoffset is a hint for PMAP_PREFER 759 * [2] <NULL,UVM_UNKNOWN_OFFSET> == don't PMAP_PREFER 760 * [3] <uobj,uoffset> == normal mapping 761 * [4] <uobj,UVM_UNKNOWN_OFFSET> == uvm_map finds offset based on VA 762 * 763 * case [4] is for kernel mappings where we don't know the offset until 764 * we've found a virtual address. note that kernel object offsets are 765 * always relative to vm_map_min(kernel_map). 766 * 767 * => if `align' is non-zero, we align the virtual address to the specified 768 * alignment. 769 * this is provided as a mechanism for large pages. 770 * 771 * => XXXCDC: need way to map in external amap? 772 */ 773 774 int 775 uvm_map(struct vm_map *map, vaddr_t *startp /* IN/OUT */, vsize_t size, 776 struct uvm_object *uobj, voff_t uoffset, vsize_t align, uvm_flag_t flags) 777 { 778 struct uvm_map_args args; 779 struct vm_map_entry *new_entry; 780 int error; 781 782 KASSERT((flags & UVM_FLAG_QUANTUM) == 0 || VM_MAP_IS_KERNEL(map)); 783 KASSERT((size & PAGE_MASK) == 0); 784 785 /* 786 * for pager_map, allocate the new entry first to avoid sleeping 787 * for memory while we have the map locked. 788 * 789 * besides, because we allocates entries for in-kernel maps 790 * a bit differently (cf. uvm_kmapent_alloc/free), we need to 791 * allocate them before locking the map. 792 */ 793 794 new_entry = NULL; 795 if (VM_MAP_USE_KMAPENT(map) || (flags & UVM_FLAG_QUANTUM) || 796 map == pager_map) { 797 new_entry = uvm_mapent_alloc(map, (flags & UVM_FLAG_NOWAIT)); 798 if (__predict_false(new_entry == NULL)) 799 return ENOMEM; 800 if (flags & UVM_FLAG_QUANTUM) 801 new_entry->flags |= UVM_MAP_QUANTUM; 802 } 803 if (map == pager_map) 804 flags |= UVM_FLAG_NOMERGE; 805 806 error = uvm_map_prepare(map, *startp, size, uobj, uoffset, align, 807 flags, &args); 808 if (!error) { 809 error = uvm_map_enter(map, &args, new_entry); 810 *startp = args.uma_start; 811 } else if (new_entry) { 812 uvm_mapent_free(new_entry); 813 } 814 815 #if defined(DEBUG) 816 if (!error && VM_MAP_IS_KERNEL(map)) { 817 uvm_km_check_empty(*startp, *startp + size, 818 (map->flags & VM_MAP_INTRSAFE) != 0); 819 } 820 #endif /* defined(DEBUG) */ 821 822 return error; 823 } 824 825 int 826 uvm_map_prepare(struct vm_map *map, vaddr_t start, vsize_t size, 827 struct uvm_object *uobj, voff_t uoffset, vsize_t align, uvm_flag_t flags, 828 struct uvm_map_args *args) 829 { 830 struct vm_map_entry *prev_entry; 831 vm_prot_t prot = UVM_PROTECTION(flags); 832 vm_prot_t maxprot = UVM_MAXPROTECTION(flags); 833 834 UVMHIST_FUNC("uvm_map_prepare"); 835 UVMHIST_CALLED(maphist); 836 837 UVMHIST_LOG(maphist, "(map=0x%x, start=0x%x, size=%d, flags=0x%x)", 838 map, start, size, flags); 839 UVMHIST_LOG(maphist, " uobj/offset 0x%x/%d", uobj, uoffset,0,0); 840 841 /* 842 * detect a popular device driver bug. 843 */ 844 845 KASSERT(doing_shutdown || curlwp != NULL || 846 (map->flags & VM_MAP_INTRSAFE)); 847 848 /* 849 * zero-sized mapping doesn't make any sense. 850 */ 851 KASSERT(size > 0); 852 853 KASSERT((~flags & (UVM_FLAG_NOWAIT | UVM_FLAG_WAITVA)) != 0); 854 855 uvm_tree_sanity(map, "map entry"); 856 857 /* 858 * check sanity of protection code 859 */ 860 861 if ((prot & maxprot) != prot) { 862 UVMHIST_LOG(maphist, "<- prot. failure: prot=0x%x, max=0x%x", 863 prot, maxprot,0,0); 864 return EACCES; 865 } 866 867 /* 868 * figure out where to put new VM range 869 */ 870 871 retry: 872 if (vm_map_lock_try(map) == FALSE) { 873 if (flags & UVM_FLAG_TRYLOCK) { 874 return EAGAIN; 875 } 876 vm_map_lock(map); /* could sleep here */ 877 } 878 if ((prev_entry = uvm_map_findspace(map, start, size, &start, 879 uobj, uoffset, align, flags)) == NULL) { 880 unsigned int timestamp; 881 882 if ((flags & UVM_FLAG_WAITVA) == 0) { 883 UVMHIST_LOG(maphist,"<- uvm_map_findspace failed!", 884 0,0,0,0); 885 vm_map_unlock(map); 886 return ENOMEM; 887 } 888 timestamp = map->timestamp; 889 UVMHIST_LOG(maphist,"waiting va timestamp=0x%x", 890 timestamp,0,0,0); 891 simple_lock(&map->flags_lock); 892 map->flags |= VM_MAP_WANTVA; 893 simple_unlock(&map->flags_lock); 894 vm_map_unlock(map); 895 896 /* 897 * wait until someone does unmap. 898 * XXX fragile locking 899 */ 900 901 simple_lock(&map->flags_lock); 902 while ((map->flags & VM_MAP_WANTVA) != 0 && 903 map->timestamp == timestamp) { 904 ltsleep(&map->header, PVM, "vmmapva", 0, 905 &map->flags_lock); 906 } 907 simple_unlock(&map->flags_lock); 908 goto retry; 909 } 910 911 #ifdef PMAP_GROWKERNEL 912 /* 913 * If the kernel pmap can't map the requested space, 914 * then allocate more resources for it. 915 */ 916 if (map == kernel_map && uvm_maxkaddr < (start + size)) 917 uvm_maxkaddr = pmap_growkernel(start + size); 918 #endif 919 920 UVMMAP_EVCNT_INCR(map_call); 921 922 /* 923 * if uobj is null, then uoffset is either a VAC hint for PMAP_PREFER 924 * [typically from uvm_map_reserve] or it is UVM_UNKNOWN_OFFSET. in 925 * either case we want to zero it before storing it in the map entry 926 * (because it looks strange and confusing when debugging...) 927 * 928 * if uobj is not null 929 * if uoffset is not UVM_UNKNOWN_OFFSET then we have a normal mapping 930 * and we do not need to change uoffset. 931 * if uoffset is UVM_UNKNOWN_OFFSET then we need to find the offset 932 * now (based on the starting address of the map). this case is 933 * for kernel object mappings where we don't know the offset until 934 * the virtual address is found (with uvm_map_findspace). the 935 * offset is the distance we are from the start of the map. 936 */ 937 938 if (uobj == NULL) { 939 uoffset = 0; 940 } else { 941 if (uoffset == UVM_UNKNOWN_OFFSET) { 942 KASSERT(UVM_OBJ_IS_KERN_OBJECT(uobj)); 943 uoffset = start - vm_map_min(kernel_map); 944 } 945 } 946 947 args->uma_flags = flags; 948 args->uma_prev = prev_entry; 949 args->uma_start = start; 950 args->uma_size = size; 951 args->uma_uobj = uobj; 952 args->uma_uoffset = uoffset; 953 954 return 0; 955 } 956 957 int 958 uvm_map_enter(struct vm_map *map, const struct uvm_map_args *args, 959 struct vm_map_entry *new_entry) 960 { 961 struct vm_map_entry *prev_entry = args->uma_prev; 962 struct vm_map_entry *dead = NULL; 963 964 const uvm_flag_t flags = args->uma_flags; 965 const vm_prot_t prot = UVM_PROTECTION(flags); 966 const vm_prot_t maxprot = UVM_MAXPROTECTION(flags); 967 const vm_inherit_t inherit = UVM_INHERIT(flags); 968 const int amapwaitflag = (flags & UVM_FLAG_NOWAIT) ? 969 AMAP_EXTEND_NOWAIT : 0; 970 const int advice = UVM_ADVICE(flags); 971 const int meflagval = (flags & UVM_FLAG_QUANTUM) ? 972 UVM_MAP_QUANTUM : 0; 973 974 vaddr_t start = args->uma_start; 975 vsize_t size = args->uma_size; 976 struct uvm_object *uobj = args->uma_uobj; 977 voff_t uoffset = args->uma_uoffset; 978 979 const int kmap = (vm_map_pmap(map) == pmap_kernel()); 980 int merged = 0; 981 int error; 982 int newetype; 983 984 UVMHIST_FUNC("uvm_map_enter"); 985 UVMHIST_CALLED(maphist); 986 987 UVMHIST_LOG(maphist, "(map=0x%x, start=0x%x, size=%d, flags=0x%x)", 988 map, start, size, flags); 989 UVMHIST_LOG(maphist, " uobj/offset 0x%x/%d", uobj, uoffset,0,0); 990 991 if (flags & UVM_FLAG_QUANTUM) { 992 KASSERT(new_entry); 993 KASSERT(new_entry->flags & UVM_MAP_QUANTUM); 994 } 995 996 if (uobj) 997 newetype = UVM_ET_OBJ; 998 else 999 newetype = 0; 1000 1001 if (flags & UVM_FLAG_COPYONW) { 1002 newetype |= UVM_ET_COPYONWRITE; 1003 if ((flags & UVM_FLAG_OVERLAY) == 0) 1004 newetype |= UVM_ET_NEEDSCOPY; 1005 } 1006 1007 /* 1008 * try and insert in map by extending previous entry, if possible. 1009 * XXX: we don't try and pull back the next entry. might be useful 1010 * for a stack, but we are currently allocating our stack in advance. 1011 */ 1012 1013 if (flags & UVM_FLAG_NOMERGE) 1014 goto nomerge; 1015 1016 if (prev_entry->end == start && 1017 prev_entry != &map->header && 1018 UVM_ET_ISCOMPATIBLE(prev_entry, newetype, uobj, meflagval, 1019 prot, maxprot, inherit, advice, 0)) { 1020 1021 if (uobj && prev_entry->offset + 1022 (prev_entry->end - prev_entry->start) != uoffset) 1023 goto forwardmerge; 1024 1025 /* 1026 * can't extend a shared amap. note: no need to lock amap to 1027 * look at refs since we don't care about its exact value. 1028 * if it is one (i.e. we have only reference) it will stay there 1029 */ 1030 1031 if (prev_entry->aref.ar_amap && 1032 amap_refs(prev_entry->aref.ar_amap) != 1) { 1033 goto forwardmerge; 1034 } 1035 1036 if (prev_entry->aref.ar_amap) { 1037 error = amap_extend(prev_entry, size, 1038 amapwaitflag | AMAP_EXTEND_FORWARDS); 1039 if (error) 1040 goto nomerge; 1041 } 1042 1043 if (kmap) 1044 UVMMAP_EVCNT_INCR(kbackmerge); 1045 else 1046 UVMMAP_EVCNT_INCR(ubackmerge); 1047 UVMHIST_LOG(maphist," starting back merge", 0, 0, 0, 0); 1048 1049 /* 1050 * drop our reference to uobj since we are extending a reference 1051 * that we already have (the ref count can not drop to zero). 1052 */ 1053 1054 if (uobj && uobj->pgops->pgo_detach) 1055 uobj->pgops->pgo_detach(uobj); 1056 1057 prev_entry->end += size; 1058 uvm_rb_fixup(map, prev_entry); 1059 1060 uvm_tree_sanity(map, "map backmerged"); 1061 1062 UVMHIST_LOG(maphist,"<- done (via backmerge)!", 0, 0, 0, 0); 1063 merged++; 1064 } 1065 1066 forwardmerge: 1067 if (prev_entry->next->start == (start + size) && 1068 prev_entry->next != &map->header && 1069 UVM_ET_ISCOMPATIBLE(prev_entry->next, newetype, uobj, meflagval, 1070 prot, maxprot, inherit, advice, 0)) { 1071 1072 if (uobj && prev_entry->next->offset != uoffset + size) 1073 goto nomerge; 1074 1075 /* 1076 * can't extend a shared amap. note: no need to lock amap to 1077 * look at refs since we don't care about its exact value. 1078 * if it is one (i.e. we have only reference) it will stay there. 1079 * 1080 * note that we also can't merge two amaps, so if we 1081 * merged with the previous entry which has an amap, 1082 * and the next entry also has an amap, we give up. 1083 * 1084 * Interesting cases: 1085 * amap, new, amap -> give up second merge (single fwd extend) 1086 * amap, new, none -> double forward extend (extend again here) 1087 * none, new, amap -> double backward extend (done here) 1088 * uobj, new, amap -> single backward extend (done here) 1089 * 1090 * XXX should we attempt to deal with someone refilling 1091 * the deallocated region between two entries that are 1092 * backed by the same amap (ie, arefs is 2, "prev" and 1093 * "next" refer to it, and adding this allocation will 1094 * close the hole, thus restoring arefs to 1 and 1095 * deallocating the "next" vm_map_entry)? -- @@@ 1096 */ 1097 1098 if (prev_entry->next->aref.ar_amap && 1099 (amap_refs(prev_entry->next->aref.ar_amap) != 1 || 1100 (merged && prev_entry->aref.ar_amap))) { 1101 goto nomerge; 1102 } 1103 1104 if (merged) { 1105 /* 1106 * Try to extend the amap of the previous entry to 1107 * cover the next entry as well. If it doesn't work 1108 * just skip on, don't actually give up, since we've 1109 * already completed the back merge. 1110 */ 1111 if (prev_entry->aref.ar_amap) { 1112 if (amap_extend(prev_entry, 1113 prev_entry->next->end - 1114 prev_entry->next->start, 1115 amapwaitflag | AMAP_EXTEND_FORWARDS)) 1116 goto nomerge; 1117 } 1118 1119 /* 1120 * Try to extend the amap of the *next* entry 1121 * back to cover the new allocation *and* the 1122 * previous entry as well (the previous merge 1123 * didn't have an amap already otherwise we 1124 * wouldn't be checking here for an amap). If 1125 * it doesn't work just skip on, again, don't 1126 * actually give up, since we've already 1127 * completed the back merge. 1128 */ 1129 else if (prev_entry->next->aref.ar_amap) { 1130 if (amap_extend(prev_entry->next, 1131 prev_entry->end - 1132 prev_entry->start, 1133 amapwaitflag | AMAP_EXTEND_BACKWARDS)) 1134 goto nomerge; 1135 } 1136 } else { 1137 /* 1138 * Pull the next entry's amap backwards to cover this 1139 * new allocation. 1140 */ 1141 if (prev_entry->next->aref.ar_amap) { 1142 error = amap_extend(prev_entry->next, size, 1143 amapwaitflag | AMAP_EXTEND_BACKWARDS); 1144 if (error) 1145 goto nomerge; 1146 } 1147 } 1148 1149 if (merged) { 1150 if (kmap) { 1151 UVMMAP_EVCNT_DECR(kbackmerge); 1152 UVMMAP_EVCNT_INCR(kbimerge); 1153 } else { 1154 UVMMAP_EVCNT_DECR(ubackmerge); 1155 UVMMAP_EVCNT_INCR(ubimerge); 1156 } 1157 } else { 1158 if (kmap) 1159 UVMMAP_EVCNT_INCR(kforwmerge); 1160 else 1161 UVMMAP_EVCNT_INCR(uforwmerge); 1162 } 1163 UVMHIST_LOG(maphist," starting forward merge", 0, 0, 0, 0); 1164 1165 /* 1166 * drop our reference to uobj since we are extending a reference 1167 * that we already have (the ref count can not drop to zero). 1168 * (if merged, we've already detached) 1169 */ 1170 if (uobj && uobj->pgops->pgo_detach && !merged) 1171 uobj->pgops->pgo_detach(uobj); 1172 1173 if (merged) { 1174 dead = prev_entry->next; 1175 prev_entry->end = dead->end; 1176 uvm_map_entry_unlink(map, dead); 1177 if (dead->aref.ar_amap != NULL) { 1178 prev_entry->aref = dead->aref; 1179 dead->aref.ar_amap = NULL; 1180 } 1181 } else { 1182 prev_entry->next->start -= size; 1183 if (prev_entry != &map->header) 1184 uvm_rb_fixup(map, prev_entry); 1185 if (uobj) 1186 prev_entry->next->offset = uoffset; 1187 } 1188 1189 uvm_tree_sanity(map, "map forwardmerged"); 1190 1191 UVMHIST_LOG(maphist,"<- done forwardmerge", 0, 0, 0, 0); 1192 merged++; 1193 } 1194 1195 nomerge: 1196 if (!merged) { 1197 UVMHIST_LOG(maphist," allocating new map entry", 0, 0, 0, 0); 1198 if (kmap) 1199 UVMMAP_EVCNT_INCR(knomerge); 1200 else 1201 UVMMAP_EVCNT_INCR(unomerge); 1202 1203 /* 1204 * allocate new entry and link it in. 1205 */ 1206 1207 if (new_entry == NULL) { 1208 new_entry = uvm_mapent_alloc(map, 1209 (flags & UVM_FLAG_NOWAIT)); 1210 if (__predict_false(new_entry == NULL)) { 1211 error = ENOMEM; 1212 goto done; 1213 } 1214 } 1215 new_entry->start = start; 1216 new_entry->end = new_entry->start + size; 1217 new_entry->object.uvm_obj = uobj; 1218 new_entry->offset = uoffset; 1219 1220 new_entry->etype = newetype; 1221 1222 if (flags & UVM_FLAG_NOMERGE) { 1223 new_entry->flags |= UVM_MAP_NOMERGE; 1224 } 1225 1226 new_entry->protection = prot; 1227 new_entry->max_protection = maxprot; 1228 new_entry->inheritance = inherit; 1229 new_entry->wired_count = 0; 1230 new_entry->advice = advice; 1231 if (flags & UVM_FLAG_OVERLAY) { 1232 1233 /* 1234 * to_add: for BSS we overallocate a little since we 1235 * are likely to extend 1236 */ 1237 1238 vaddr_t to_add = (flags & UVM_FLAG_AMAPPAD) ? 1239 UVM_AMAP_CHUNK << PAGE_SHIFT : 0; 1240 struct vm_amap *amap = amap_alloc(size, to_add, 1241 (flags & UVM_FLAG_NOWAIT) ? M_NOWAIT : M_WAITOK); 1242 if (__predict_false(amap == NULL)) { 1243 error = ENOMEM; 1244 goto done; 1245 } 1246 new_entry->aref.ar_pageoff = 0; 1247 new_entry->aref.ar_amap = amap; 1248 } else { 1249 new_entry->aref.ar_pageoff = 0; 1250 new_entry->aref.ar_amap = NULL; 1251 } 1252 uvm_map_entry_link(map, prev_entry, new_entry); 1253 1254 /* 1255 * Update the free space hint 1256 */ 1257 1258 if ((map->first_free == prev_entry) && 1259 (prev_entry->end >= new_entry->start)) 1260 map->first_free = new_entry; 1261 1262 new_entry = NULL; 1263 } 1264 1265 map->size += size; 1266 1267 UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0); 1268 1269 error = 0; 1270 done: 1271 vm_map_unlock(map); 1272 if (new_entry) { 1273 if (error == 0) { 1274 KDASSERT(merged); 1275 uvm_mapent_free_merged(map, new_entry); 1276 } else { 1277 uvm_mapent_free(new_entry); 1278 } 1279 } 1280 if (dead) { 1281 KDASSERT(merged); 1282 uvm_mapent_free_merged(map, dead); 1283 } 1284 return error; 1285 } 1286 1287 /* 1288 * uvm_map_lookup_entry: find map entry at or before an address 1289 * 1290 * => map must at least be read-locked by caller 1291 * => entry is returned in "entry" 1292 * => return value is true if address is in the returned entry 1293 */ 1294 1295 boolean_t 1296 uvm_map_lookup_entry(struct vm_map *map, vaddr_t address, 1297 struct vm_map_entry **entry /* OUT */) 1298 { 1299 struct vm_map_entry *cur; 1300 boolean_t use_tree = FALSE; 1301 UVMHIST_FUNC("uvm_map_lookup_entry"); 1302 UVMHIST_CALLED(maphist); 1303 1304 UVMHIST_LOG(maphist,"(map=0x%x,addr=0x%x,ent=0x%x)", 1305 map, address, entry, 0); 1306 1307 /* 1308 * start looking either from the head of the 1309 * list, or from the hint. 1310 */ 1311 1312 simple_lock(&map->hint_lock); 1313 cur = map->hint; 1314 simple_unlock(&map->hint_lock); 1315 1316 if (cur == &map->header) 1317 cur = cur->next; 1318 1319 UVMMAP_EVCNT_INCR(mlk_call); 1320 if (address >= cur->start) { 1321 1322 /* 1323 * go from hint to end of list. 1324 * 1325 * but first, make a quick check to see if 1326 * we are already looking at the entry we 1327 * want (which is usually the case). 1328 * note also that we don't need to save the hint 1329 * here... it is the same hint (unless we are 1330 * at the header, in which case the hint didn't 1331 * buy us anything anyway). 1332 */ 1333 1334 if (cur != &map->header && cur->end > address) { 1335 UVMMAP_EVCNT_INCR(mlk_hint); 1336 *entry = cur; 1337 UVMHIST_LOG(maphist,"<- got it via hint (0x%x)", 1338 cur, 0, 0, 0); 1339 return (TRUE); 1340 } 1341 1342 if (map->nentries > 30) 1343 use_tree = TRUE; 1344 } else { 1345 1346 /* 1347 * invalid hint. use tree. 1348 */ 1349 use_tree = TRUE; 1350 } 1351 1352 uvm_tree_sanity(map, __func__); 1353 1354 if (use_tree) { 1355 struct vm_map_entry *prev = &map->header; 1356 cur = RB_ROOT(&map->rbhead); 1357 1358 /* 1359 * Simple lookup in the tree. Happens when the hint is 1360 * invalid, or nentries reach a threshold. 1361 */ 1362 while (cur) { 1363 if (address >= cur->start) { 1364 if (address < cur->end) { 1365 *entry = cur; 1366 goto got; 1367 } 1368 prev = cur; 1369 cur = RB_RIGHT(cur, rb_entry); 1370 } else 1371 cur = RB_LEFT(cur, rb_entry); 1372 } 1373 *entry = prev; 1374 goto failed; 1375 } 1376 1377 /* 1378 * search linearly 1379 */ 1380 1381 while (cur != &map->header) { 1382 if (cur->end > address) { 1383 if (address >= cur->start) { 1384 /* 1385 * save this lookup for future 1386 * hints, and return 1387 */ 1388 1389 *entry = cur; 1390 got: 1391 SAVE_HINT(map, map->hint, *entry); 1392 UVMHIST_LOG(maphist,"<- search got it (0x%x)", 1393 cur, 0, 0, 0); 1394 KDASSERT((*entry)->start <= address); 1395 KDASSERT(address < (*entry)->end); 1396 return (TRUE); 1397 } 1398 break; 1399 } 1400 cur = cur->next; 1401 } 1402 *entry = cur->prev; 1403 failed: 1404 SAVE_HINT(map, map->hint, *entry); 1405 UVMHIST_LOG(maphist,"<- failed!",0,0,0,0); 1406 KDASSERT((*entry) == &map->header || (*entry)->end <= address); 1407 KDASSERT((*entry)->next == &map->header || 1408 address < (*entry)->next->start); 1409 return (FALSE); 1410 } 1411 1412 /* 1413 * See if the range between start and start + length fits in the gap 1414 * entry->next->start and entry->end. Returns 1 if fits, 0 if doesn't 1415 * fit, and -1 address wraps around. 1416 */ 1417 static int 1418 uvm_map_space_avail(vaddr_t *start, vsize_t length, voff_t uoffset, 1419 vsize_t align, int topdown, struct vm_map_entry *entry) 1420 { 1421 vaddr_t end; 1422 1423 #ifdef PMAP_PREFER 1424 /* 1425 * push start address forward as needed to avoid VAC alias problems. 1426 * we only do this if a valid offset is specified. 1427 */ 1428 1429 if (uoffset != UVM_UNKNOWN_OFFSET) 1430 PMAP_PREFER(uoffset, start, length, topdown); 1431 #endif 1432 if (align != 0) { 1433 if ((*start & (align - 1)) != 0) { 1434 if (topdown) 1435 *start &= ~(align - 1); 1436 else 1437 *start = roundup(*start, align); 1438 } 1439 /* 1440 * XXX Should we PMAP_PREFER() here again? 1441 * eh...i think we're okay 1442 */ 1443 } 1444 1445 /* 1446 * Find the end of the proposed new region. Be sure we didn't 1447 * wrap around the address; if so, we lose. Otherwise, if the 1448 * proposed new region fits before the next entry, we win. 1449 */ 1450 1451 end = *start + length; 1452 if (end < *start) 1453 return (-1); 1454 1455 if (entry->next->start >= end && *start >= entry->end) 1456 return (1); 1457 1458 return (0); 1459 } 1460 1461 /* 1462 * uvm_map_findspace: find "length" sized space in "map". 1463 * 1464 * => "hint" is a hint about where we want it, unless UVM_FLAG_FIXED is 1465 * set in "flags" (in which case we insist on using "hint"). 1466 * => "result" is VA returned 1467 * => uobj/uoffset are to be used to handle VAC alignment, if required 1468 * => if "align" is non-zero, we attempt to align to that value. 1469 * => caller must at least have read-locked map 1470 * => returns NULL on failure, or pointer to prev. map entry if success 1471 * => note this is a cross between the old vm_map_findspace and vm_map_find 1472 */ 1473 1474 struct vm_map_entry * 1475 uvm_map_findspace(struct vm_map *map, vaddr_t hint, vsize_t length, 1476 vaddr_t *result /* OUT */, struct uvm_object *uobj, voff_t uoffset, 1477 vsize_t align, int flags) 1478 { 1479 struct vm_map_entry *entry; 1480 struct vm_map_entry *child, *prev, *tmp; 1481 vaddr_t orig_hint; 1482 const int topdown = map->flags & VM_MAP_TOPDOWN; 1483 UVMHIST_FUNC("uvm_map_findspace"); 1484 UVMHIST_CALLED(maphist); 1485 1486 UVMHIST_LOG(maphist, "(map=0x%x, hint=0x%x, len=%d, flags=0x%x)", 1487 map, hint, length, flags); 1488 KASSERT((align & (align - 1)) == 0); 1489 KASSERT((flags & UVM_FLAG_FIXED) == 0 || align == 0); 1490 1491 uvm_tree_sanity(map, "map_findspace entry"); 1492 1493 /* 1494 * remember the original hint. if we are aligning, then we 1495 * may have to try again with no alignment constraint if 1496 * we fail the first time. 1497 */ 1498 1499 orig_hint = hint; 1500 if (hint < vm_map_min(map)) { /* check ranges ... */ 1501 if (flags & UVM_FLAG_FIXED) { 1502 UVMHIST_LOG(maphist,"<- VA below map range",0,0,0,0); 1503 return (NULL); 1504 } 1505 hint = vm_map_min(map); 1506 } 1507 if (hint > vm_map_max(map)) { 1508 UVMHIST_LOG(maphist,"<- VA 0x%x > range [0x%x->0x%x]", 1509 hint, vm_map_min(map), vm_map_max(map), 0); 1510 return (NULL); 1511 } 1512 1513 /* 1514 * Look for the first possible address; if there's already 1515 * something at this address, we have to start after it. 1516 */ 1517 1518 /* 1519 * @@@: there are four, no, eight cases to consider. 1520 * 1521 * 0: found, fixed, bottom up -> fail 1522 * 1: found, fixed, top down -> fail 1523 * 2: found, not fixed, bottom up -> start after entry->end, 1524 * loop up 1525 * 3: found, not fixed, top down -> start before entry->start, 1526 * loop down 1527 * 4: not found, fixed, bottom up -> check entry->next->start, fail 1528 * 5: not found, fixed, top down -> check entry->next->start, fail 1529 * 6: not found, not fixed, bottom up -> check entry->next->start, 1530 * loop up 1531 * 7: not found, not fixed, top down -> check entry->next->start, 1532 * loop down 1533 * 1534 * as you can see, it reduces to roughly five cases, and that 1535 * adding top down mapping only adds one unique case (without 1536 * it, there would be four cases). 1537 */ 1538 1539 if ((flags & UVM_FLAG_FIXED) == 0 && hint == vm_map_min(map)) { 1540 entry = map->first_free; 1541 } else { 1542 if (uvm_map_lookup_entry(map, hint, &entry)) { 1543 /* "hint" address already in use ... */ 1544 if (flags & UVM_FLAG_FIXED) { 1545 UVMHIST_LOG(maphist, "<- fixed & VA in use", 1546 0, 0, 0, 0); 1547 return (NULL); 1548 } 1549 if (topdown) 1550 /* Start from lower gap. */ 1551 entry = entry->prev; 1552 } else if (flags & UVM_FLAG_FIXED) { 1553 if (entry->next->start >= hint + length && 1554 hint + length > hint) 1555 goto found; 1556 1557 /* "hint" address is gap but too small */ 1558 UVMHIST_LOG(maphist, "<- fixed mapping failed", 1559 0, 0, 0, 0); 1560 return (NULL); /* only one shot at it ... */ 1561 } else { 1562 /* 1563 * See if given hint fits in this gap. 1564 */ 1565 switch (uvm_map_space_avail(&hint, length, 1566 uoffset, align, topdown, entry)) { 1567 case 1: 1568 goto found; 1569 case -1: 1570 goto wraparound; 1571 } 1572 1573 if (topdown) { 1574 /* 1575 * Still there is a chance to fit 1576 * if hint > entry->end. 1577 */ 1578 } else { 1579 /* Start from higher gap. */ 1580 entry = entry->next; 1581 if (entry == &map->header) 1582 goto notfound; 1583 goto nextgap; 1584 } 1585 } 1586 } 1587 1588 /* 1589 * Note that all UVM_FLAGS_FIXED case is already handled. 1590 */ 1591 KDASSERT((flags & UVM_FLAG_FIXED) == 0); 1592 1593 /* Try to find the space in the red-black tree */ 1594 1595 /* Check slot before any entry */ 1596 hint = topdown ? entry->next->start - length : entry->end; 1597 switch (uvm_map_space_avail(&hint, length, uoffset, align, 1598 topdown, entry)) { 1599 case 1: 1600 goto found; 1601 case -1: 1602 goto wraparound; 1603 } 1604 1605 nextgap: 1606 KDASSERT((flags & UVM_FLAG_FIXED) == 0); 1607 /* If there is not enough space in the whole tree, we fail */ 1608 tmp = RB_ROOT(&map->rbhead); 1609 if (tmp == NULL || tmp->space < length) 1610 goto notfound; 1611 1612 prev = NULL; /* previous candidate */ 1613 1614 /* Find an entry close to hint that has enough space */ 1615 for (; tmp;) { 1616 KASSERT(tmp->next->start == tmp->end + tmp->ownspace); 1617 if (topdown) { 1618 if (tmp->next->start < hint + length && 1619 (prev == NULL || tmp->end > prev->end)) { 1620 if (tmp->ownspace >= length) 1621 prev = tmp; 1622 else if ((child = RB_LEFT(tmp, rb_entry)) 1623 != NULL && child->space >= length) 1624 prev = tmp; 1625 } 1626 } else { 1627 if (tmp->end >= hint && 1628 (prev == NULL || tmp->end < prev->end)) { 1629 if (tmp->ownspace >= length) 1630 prev = tmp; 1631 else if ((child = RB_RIGHT(tmp, rb_entry)) 1632 != NULL && child->space >= length) 1633 prev = tmp; 1634 } 1635 } 1636 if (tmp->next->start < hint + length) 1637 child = RB_RIGHT(tmp, rb_entry); 1638 else if (tmp->end > hint) 1639 child = RB_LEFT(tmp, rb_entry); 1640 else { 1641 if (tmp->ownspace >= length) 1642 break; 1643 if (topdown) 1644 child = RB_LEFT(tmp, rb_entry); 1645 else 1646 child = RB_RIGHT(tmp, rb_entry); 1647 } 1648 if (child == NULL || child->space < length) 1649 break; 1650 tmp = child; 1651 } 1652 1653 if (tmp != NULL && tmp->start < hint && hint < tmp->next->start) { 1654 /* 1655 * Check if the entry that we found satifies the 1656 * space requirement 1657 */ 1658 if (topdown) { 1659 if (hint > tmp->next->start - length) 1660 hint = tmp->next->start - length; 1661 } else { 1662 if (hint < tmp->end) 1663 hint = tmp->end; 1664 } 1665 switch (uvm_map_space_avail(&hint, length, uoffset, align, 1666 topdown, tmp)) { 1667 case 1: 1668 entry = tmp; 1669 goto found; 1670 case -1: 1671 goto wraparound; 1672 } 1673 if (tmp->ownspace >= length) 1674 goto listsearch; 1675 } 1676 if (prev == NULL) 1677 goto notfound; 1678 1679 if (topdown) { 1680 KASSERT(orig_hint >= prev->next->start - length || 1681 prev->next->start - length > prev->next->start); 1682 hint = prev->next->start - length; 1683 } else { 1684 KASSERT(orig_hint <= prev->end); 1685 hint = prev->end; 1686 } 1687 switch (uvm_map_space_avail(&hint, length, uoffset, align, 1688 topdown, prev)) { 1689 case 1: 1690 entry = prev; 1691 goto found; 1692 case -1: 1693 goto wraparound; 1694 } 1695 if (prev->ownspace >= length) 1696 goto listsearch; 1697 1698 if (topdown) 1699 tmp = RB_LEFT(prev, rb_entry); 1700 else 1701 tmp = RB_RIGHT(prev, rb_entry); 1702 for (;;) { 1703 KASSERT(tmp && tmp->space >= length); 1704 if (topdown) 1705 child = RB_RIGHT(tmp, rb_entry); 1706 else 1707 child = RB_LEFT(tmp, rb_entry); 1708 if (child && child->space >= length) { 1709 tmp = child; 1710 continue; 1711 } 1712 if (tmp->ownspace >= length) 1713 break; 1714 if (topdown) 1715 tmp = RB_LEFT(tmp, rb_entry); 1716 else 1717 tmp = RB_RIGHT(tmp, rb_entry); 1718 } 1719 1720 if (topdown) { 1721 KASSERT(orig_hint >= tmp->next->start - length || 1722 tmp->next->start - length > tmp->next->start); 1723 hint = tmp->next->start - length; 1724 } else { 1725 KASSERT(orig_hint <= tmp->end); 1726 hint = tmp->end; 1727 } 1728 switch (uvm_map_space_avail(&hint, length, uoffset, align, 1729 topdown, tmp)) { 1730 case 1: 1731 entry = tmp; 1732 goto found; 1733 case -1: 1734 goto wraparound; 1735 } 1736 1737 /* 1738 * The tree fails to find an entry because of offset or alignment 1739 * restrictions. Search the list instead. 1740 */ 1741 listsearch: 1742 /* 1743 * Look through the rest of the map, trying to fit a new region in 1744 * the gap between existing regions, or after the very last region. 1745 * note: entry->end = base VA of current gap, 1746 * entry->next->start = VA of end of current gap 1747 */ 1748 1749 for (;;) { 1750 /* Update hint for current gap. */ 1751 hint = topdown ? entry->next->start - length : entry->end; 1752 1753 /* See if it fits. */ 1754 switch (uvm_map_space_avail(&hint, length, uoffset, align, 1755 topdown, entry)) { 1756 case 1: 1757 goto found; 1758 case -1: 1759 goto wraparound; 1760 } 1761 1762 /* Advance to next/previous gap */ 1763 if (topdown) { 1764 if (entry == &map->header) { 1765 UVMHIST_LOG(maphist, "<- failed (off start)", 1766 0,0,0,0); 1767 goto notfound; 1768 } 1769 entry = entry->prev; 1770 } else { 1771 entry = entry->next; 1772 if (entry == &map->header) { 1773 UVMHIST_LOG(maphist, "<- failed (off end)", 1774 0,0,0,0); 1775 goto notfound; 1776 } 1777 } 1778 } 1779 1780 found: 1781 SAVE_HINT(map, map->hint, entry); 1782 *result = hint; 1783 UVMHIST_LOG(maphist,"<- got it! (result=0x%x)", hint, 0,0,0); 1784 KASSERT( topdown || hint >= orig_hint); 1785 KASSERT(!topdown || hint <= orig_hint); 1786 KASSERT(entry->end <= hint); 1787 KASSERT(hint + length <= entry->next->start); 1788 return (entry); 1789 1790 wraparound: 1791 UVMHIST_LOG(maphist, "<- failed (wrap around)", 0,0,0,0); 1792 1793 return (NULL); 1794 1795 notfound: 1796 UVMHIST_LOG(maphist, "<- failed (notfound)", 0,0,0,0); 1797 1798 return (NULL); 1799 } 1800 1801 /* 1802 * U N M A P - m a i n h e l p e r f u n c t i o n s 1803 */ 1804 1805 /* 1806 * uvm_unmap_remove: remove mappings from a vm_map (from "start" up to "stop") 1807 * 1808 * => caller must check alignment and size 1809 * => map must be locked by caller 1810 * => we return a list of map entries that we've remove from the map 1811 * in "entry_list" 1812 */ 1813 1814 void 1815 uvm_unmap_remove(struct vm_map *map, vaddr_t start, vaddr_t end, 1816 struct vm_map_entry **entry_list /* OUT */, 1817 struct uvm_mapent_reservation *umr, int flags) 1818 { 1819 struct vm_map_entry *entry, *first_entry, *next; 1820 vaddr_t len; 1821 UVMHIST_FUNC("uvm_unmap_remove"); UVMHIST_CALLED(maphist); 1822 1823 UVMHIST_LOG(maphist,"(map=0x%x, start=0x%x, end=0x%x)", 1824 map, start, end, 0); 1825 VM_MAP_RANGE_CHECK(map, start, end); 1826 1827 uvm_tree_sanity(map, "unmap_remove entry"); 1828 1829 /* 1830 * find first entry 1831 */ 1832 1833 if (uvm_map_lookup_entry(map, start, &first_entry) == TRUE) { 1834 /* clip and go... */ 1835 entry = first_entry; 1836 UVM_MAP_CLIP_START(map, entry, start, umr); 1837 /* critical! prevents stale hint */ 1838 SAVE_HINT(map, entry, entry->prev); 1839 } else { 1840 entry = first_entry->next; 1841 } 1842 1843 /* 1844 * Save the free space hint 1845 */ 1846 1847 if (map->first_free->start >= start) 1848 map->first_free = entry->prev; 1849 1850 /* 1851 * note: we now re-use first_entry for a different task. we remove 1852 * a number of map entries from the map and save them in a linked 1853 * list headed by "first_entry". once we remove them from the map 1854 * the caller should unlock the map and drop the references to the 1855 * backing objects [c.f. uvm_unmap_detach]. the object is to 1856 * separate unmapping from reference dropping. why? 1857 * [1] the map has to be locked for unmapping 1858 * [2] the map need not be locked for reference dropping 1859 * [3] dropping references may trigger pager I/O, and if we hit 1860 * a pager that does synchronous I/O we may have to wait for it. 1861 * [4] we would like all waiting for I/O to occur with maps unlocked 1862 * so that we don't block other threads. 1863 */ 1864 1865 first_entry = NULL; 1866 *entry_list = NULL; 1867 1868 /* 1869 * break up the area into map entry sized regions and unmap. note 1870 * that all mappings have to be removed before we can even consider 1871 * dropping references to amaps or VM objects (otherwise we could end 1872 * up with a mapping to a page on the free list which would be very bad) 1873 */ 1874 1875 while ((entry != &map->header) && (entry->start < end)) { 1876 KASSERT((entry->flags & UVM_MAP_FIRST) == 0); 1877 1878 UVM_MAP_CLIP_END(map, entry, end, umr); 1879 next = entry->next; 1880 len = entry->end - entry->start; 1881 1882 /* 1883 * unwire before removing addresses from the pmap; otherwise 1884 * unwiring will put the entries back into the pmap (XXX). 1885 */ 1886 1887 if (VM_MAPENT_ISWIRED(entry)) { 1888 uvm_map_entry_unwire(map, entry); 1889 } 1890 if (flags & UVM_FLAG_VAONLY) { 1891 1892 /* nothing */ 1893 1894 } else if ((map->flags & VM_MAP_PAGEABLE) == 0) { 1895 1896 /* 1897 * if the map is non-pageable, any pages mapped there 1898 * must be wired and entered with pmap_kenter_pa(), 1899 * and we should free any such pages immediately. 1900 * this is mostly used for kmem_map and mb_map. 1901 */ 1902 1903 if ((entry->flags & UVM_MAP_KMAPENT) == 0) { 1904 uvm_km_pgremove_intrsafe(entry->start, 1905 entry->end); 1906 pmap_kremove(entry->start, len); 1907 } 1908 } else if (UVM_ET_ISOBJ(entry) && 1909 UVM_OBJ_IS_KERN_OBJECT(entry->object.uvm_obj)) { 1910 KASSERT(vm_map_pmap(map) == pmap_kernel()); 1911 1912 /* 1913 * note: kernel object mappings are currently used in 1914 * two ways: 1915 * [1] "normal" mappings of pages in the kernel object 1916 * [2] uvm_km_valloc'd allocations in which we 1917 * pmap_enter in some non-kernel-object page 1918 * (e.g. vmapbuf). 1919 * 1920 * for case [1], we need to remove the mapping from 1921 * the pmap and then remove the page from the kernel 1922 * object (because, once pages in a kernel object are 1923 * unmapped they are no longer needed, unlike, say, 1924 * a vnode where you might want the data to persist 1925 * until flushed out of a queue). 1926 * 1927 * for case [2], we need to remove the mapping from 1928 * the pmap. there shouldn't be any pages at the 1929 * specified offset in the kernel object [but it 1930 * doesn't hurt to call uvm_km_pgremove just to be 1931 * safe?] 1932 * 1933 * uvm_km_pgremove currently does the following: 1934 * for pages in the kernel object in range: 1935 * - drops the swap slot 1936 * - uvm_pagefree the page 1937 */ 1938 1939 /* 1940 * remove mappings from pmap and drop the pages 1941 * from the object. offsets are always relative 1942 * to vm_map_min(kernel_map). 1943 */ 1944 1945 pmap_remove(pmap_kernel(), entry->start, 1946 entry->start + len); 1947 uvm_km_pgremove(entry->start, entry->end); 1948 1949 /* 1950 * null out kernel_object reference, we've just 1951 * dropped it 1952 */ 1953 1954 entry->etype &= ~UVM_ET_OBJ; 1955 entry->object.uvm_obj = NULL; 1956 } else if (UVM_ET_ISOBJ(entry) || entry->aref.ar_amap) { 1957 1958 /* 1959 * remove mappings the standard way. 1960 */ 1961 1962 pmap_remove(map->pmap, entry->start, entry->end); 1963 } 1964 1965 #if defined(DEBUG) 1966 if ((entry->flags & UVM_MAP_KMAPENT) == 0) { 1967 1968 /* 1969 * check if there's remaining mapping, 1970 * which is a bug in caller. 1971 */ 1972 1973 vaddr_t va; 1974 for (va = entry->start; va < entry->end; 1975 va += PAGE_SIZE) { 1976 if (pmap_extract(vm_map_pmap(map), va, NULL)) { 1977 panic("uvm_unmap_remove: has mapping"); 1978 } 1979 } 1980 1981 if (VM_MAP_IS_KERNEL(map)) { 1982 uvm_km_check_empty(entry->start, entry->end, 1983 (map->flags & VM_MAP_INTRSAFE) != 0); 1984 } 1985 } 1986 #endif /* defined(DEBUG) */ 1987 1988 /* 1989 * remove entry from map and put it on our list of entries 1990 * that we've nuked. then go to next entry. 1991 */ 1992 1993 UVMHIST_LOG(maphist, " removed map entry 0x%x", entry, 0, 0,0); 1994 1995 /* critical! prevents stale hint */ 1996 SAVE_HINT(map, entry, entry->prev); 1997 1998 uvm_map_entry_unlink(map, entry); 1999 KASSERT(map->size >= len); 2000 map->size -= len; 2001 entry->prev = NULL; 2002 entry->next = first_entry; 2003 first_entry = entry; 2004 entry = next; 2005 } 2006 if ((map->flags & VM_MAP_DYING) == 0) { 2007 pmap_update(vm_map_pmap(map)); 2008 } 2009 2010 uvm_tree_sanity(map, "unmap_remove leave"); 2011 2012 /* 2013 * now we've cleaned up the map and are ready for the caller to drop 2014 * references to the mapped objects. 2015 */ 2016 2017 *entry_list = first_entry; 2018 UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0); 2019 2020 simple_lock(&map->flags_lock); 2021 if (map->flags & VM_MAP_WANTVA) { 2022 map->flags &= ~VM_MAP_WANTVA; 2023 wakeup(&map->header); 2024 } 2025 simple_unlock(&map->flags_lock); 2026 } 2027 2028 /* 2029 * uvm_unmap_detach: drop references in a chain of map entries 2030 * 2031 * => we will free the map entries as we traverse the list. 2032 */ 2033 2034 void 2035 uvm_unmap_detach(struct vm_map_entry *first_entry, int flags) 2036 { 2037 struct vm_map_entry *next_entry; 2038 UVMHIST_FUNC("uvm_unmap_detach"); UVMHIST_CALLED(maphist); 2039 2040 while (first_entry) { 2041 KASSERT(!VM_MAPENT_ISWIRED(first_entry)); 2042 UVMHIST_LOG(maphist, 2043 " detach 0x%x: amap=0x%x, obj=0x%x, submap?=%d", 2044 first_entry, first_entry->aref.ar_amap, 2045 first_entry->object.uvm_obj, 2046 UVM_ET_ISSUBMAP(first_entry)); 2047 2048 /* 2049 * drop reference to amap, if we've got one 2050 */ 2051 2052 if (first_entry->aref.ar_amap) 2053 uvm_map_unreference_amap(first_entry, flags); 2054 2055 /* 2056 * drop reference to our backing object, if we've got one 2057 */ 2058 2059 KASSERT(!UVM_ET_ISSUBMAP(first_entry)); 2060 if (UVM_ET_ISOBJ(first_entry) && 2061 first_entry->object.uvm_obj->pgops->pgo_detach) { 2062 (*first_entry->object.uvm_obj->pgops->pgo_detach) 2063 (first_entry->object.uvm_obj); 2064 } 2065 next_entry = first_entry->next; 2066 uvm_mapent_free(first_entry); 2067 first_entry = next_entry; 2068 } 2069 UVMHIST_LOG(maphist, "<- done", 0,0,0,0); 2070 } 2071 2072 /* 2073 * E X T R A C T I O N F U N C T I O N S 2074 */ 2075 2076 /* 2077 * uvm_map_reserve: reserve space in a vm_map for future use. 2078 * 2079 * => we reserve space in a map by putting a dummy map entry in the 2080 * map (dummy means obj=NULL, amap=NULL, prot=VM_PROT_NONE) 2081 * => map should be unlocked (we will write lock it) 2082 * => we return true if we were able to reserve space 2083 * => XXXCDC: should be inline? 2084 */ 2085 2086 int 2087 uvm_map_reserve(struct vm_map *map, vsize_t size, 2088 vaddr_t offset /* hint for pmap_prefer */, 2089 vsize_t align /* alignment hint */, 2090 vaddr_t *raddr /* IN:hint, OUT: reserved VA */, 2091 uvm_flag_t flags /* UVM_FLAG_FIXED or 0 */) 2092 { 2093 UVMHIST_FUNC("uvm_map_reserve"); UVMHIST_CALLED(maphist); 2094 2095 UVMHIST_LOG(maphist, "(map=0x%x, size=0x%x, offset=0x%x,addr=0x%x)", 2096 map,size,offset,raddr); 2097 2098 size = round_page(size); 2099 2100 /* 2101 * reserve some virtual space. 2102 */ 2103 2104 if (uvm_map(map, raddr, size, NULL, offset, 0, 2105 UVM_MAPFLAG(UVM_PROT_NONE, UVM_PROT_NONE, UVM_INH_NONE, 2106 UVM_ADV_RANDOM, UVM_FLAG_NOMERGE|flags)) != 0) { 2107 UVMHIST_LOG(maphist, "<- done (no VM)", 0,0,0,0); 2108 return (FALSE); 2109 } 2110 2111 UVMHIST_LOG(maphist, "<- done (*raddr=0x%x)", *raddr,0,0,0); 2112 return (TRUE); 2113 } 2114 2115 /* 2116 * uvm_map_replace: replace a reserved (blank) area of memory with 2117 * real mappings. 2118 * 2119 * => caller must WRITE-LOCK the map 2120 * => we return TRUE if replacement was a success 2121 * => we expect the newents chain to have nnewents entrys on it and 2122 * we expect newents->prev to point to the last entry on the list 2123 * => note newents is allowed to be NULL 2124 */ 2125 2126 int 2127 uvm_map_replace(struct vm_map *map, vaddr_t start, vaddr_t end, 2128 struct vm_map_entry *newents, int nnewents) 2129 { 2130 struct vm_map_entry *oldent, *last; 2131 2132 uvm_tree_sanity(map, "map_replace entry"); 2133 2134 /* 2135 * first find the blank map entry at the specified address 2136 */ 2137 2138 if (!uvm_map_lookup_entry(map, start, &oldent)) { 2139 return (FALSE); 2140 } 2141 2142 /* 2143 * check to make sure we have a proper blank entry 2144 */ 2145 2146 if (end < oldent->end && !VM_MAP_USE_KMAPENT(map)) { 2147 UVM_MAP_CLIP_END(map, oldent, end, NULL); 2148 } 2149 if (oldent->start != start || oldent->end != end || 2150 oldent->object.uvm_obj != NULL || oldent->aref.ar_amap != NULL) { 2151 return (FALSE); 2152 } 2153 2154 #ifdef DIAGNOSTIC 2155 2156 /* 2157 * sanity check the newents chain 2158 */ 2159 2160 { 2161 struct vm_map_entry *tmpent = newents; 2162 int nent = 0; 2163 vaddr_t cur = start; 2164 2165 while (tmpent) { 2166 nent++; 2167 if (tmpent->start < cur) 2168 panic("uvm_map_replace1"); 2169 if (tmpent->start > tmpent->end || tmpent->end > end) { 2170 printf("tmpent->start=0x%lx, tmpent->end=0x%lx, end=0x%lx\n", 2171 tmpent->start, tmpent->end, end); 2172 panic("uvm_map_replace2"); 2173 } 2174 cur = tmpent->end; 2175 if (tmpent->next) { 2176 if (tmpent->next->prev != tmpent) 2177 panic("uvm_map_replace3"); 2178 } else { 2179 if (newents->prev != tmpent) 2180 panic("uvm_map_replace4"); 2181 } 2182 tmpent = tmpent->next; 2183 } 2184 if (nent != nnewents) 2185 panic("uvm_map_replace5"); 2186 } 2187 #endif 2188 2189 /* 2190 * map entry is a valid blank! replace it. (this does all the 2191 * work of map entry link/unlink...). 2192 */ 2193 2194 if (newents) { 2195 last = newents->prev; 2196 2197 /* critical: flush stale hints out of map */ 2198 SAVE_HINT(map, map->hint, newents); 2199 if (map->first_free == oldent) 2200 map->first_free = last; 2201 2202 last->next = oldent->next; 2203 last->next->prev = last; 2204 2205 /* Fix RB tree */ 2206 uvm_rb_remove(map, oldent); 2207 2208 newents->prev = oldent->prev; 2209 newents->prev->next = newents; 2210 map->nentries = map->nentries + (nnewents - 1); 2211 2212 /* Fixup the RB tree */ 2213 { 2214 int i; 2215 struct vm_map_entry *tmp; 2216 2217 tmp = newents; 2218 for (i = 0; i < nnewents && tmp; i++) { 2219 uvm_rb_insert(map, tmp); 2220 tmp = tmp->next; 2221 } 2222 } 2223 } else { 2224 2225 /* critical: flush stale hints out of map */ 2226 SAVE_HINT(map, map->hint, oldent->prev); 2227 if (map->first_free == oldent) 2228 map->first_free = oldent->prev; 2229 2230 /* NULL list of new entries: just remove the old one */ 2231 uvm_map_entry_unlink(map, oldent); 2232 } 2233 2234 uvm_tree_sanity(map, "map_replace leave"); 2235 2236 /* 2237 * now we can free the old blank entry and return. 2238 */ 2239 2240 uvm_mapent_free(oldent); 2241 return (TRUE); 2242 } 2243 2244 /* 2245 * uvm_map_extract: extract a mapping from a map and put it somewhere 2246 * (maybe removing the old mapping) 2247 * 2248 * => maps should be unlocked (we will write lock them) 2249 * => returns 0 on success, error code otherwise 2250 * => start must be page aligned 2251 * => len must be page sized 2252 * => flags: 2253 * UVM_EXTRACT_REMOVE: remove mappings from srcmap 2254 * UVM_EXTRACT_CONTIG: abort if unmapped area (advisory only) 2255 * UVM_EXTRACT_QREF: for a temporary extraction do quick obj refs 2256 * UVM_EXTRACT_FIXPROT: set prot to maxprot as we go 2257 * >>>NOTE: if you set REMOVE, you are not allowed to use CONTIG or QREF!<<< 2258 * >>>NOTE: QREF's must be unmapped via the QREF path, thus should only 2259 * be used from within the kernel in a kernel level map <<< 2260 */ 2261 2262 int 2263 uvm_map_extract(struct vm_map *srcmap, vaddr_t start, vsize_t len, 2264 struct vm_map *dstmap, vaddr_t *dstaddrp, int flags) 2265 { 2266 vaddr_t dstaddr, end, newend, oldoffset, fudge, orig_fudge; 2267 struct vm_map_entry *chain, *endchain, *entry, *orig_entry, *newentry, 2268 *deadentry, *oldentry; 2269 vsize_t elen; 2270 int nchain, error, copy_ok; 2271 UVMHIST_FUNC("uvm_map_extract"); UVMHIST_CALLED(maphist); 2272 2273 UVMHIST_LOG(maphist,"(srcmap=0x%x,start=0x%x, len=0x%x", srcmap, start, 2274 len,0); 2275 UVMHIST_LOG(maphist," ...,dstmap=0x%x, flags=0x%x)", dstmap,flags,0,0); 2276 2277 uvm_tree_sanity(srcmap, "map_extract src enter"); 2278 uvm_tree_sanity(dstmap, "map_extract dst enter"); 2279 2280 /* 2281 * step 0: sanity check: start must be on a page boundary, length 2282 * must be page sized. can't ask for CONTIG/QREF if you asked for 2283 * REMOVE. 2284 */ 2285 2286 KASSERT((start & PAGE_MASK) == 0 && (len & PAGE_MASK) == 0); 2287 KASSERT((flags & UVM_EXTRACT_REMOVE) == 0 || 2288 (flags & (UVM_EXTRACT_CONTIG|UVM_EXTRACT_QREF)) == 0); 2289 2290 /* 2291 * step 1: reserve space in the target map for the extracted area 2292 */ 2293 2294 if ((flags & UVM_EXTRACT_RESERVED) == 0) { 2295 dstaddr = vm_map_min(dstmap); 2296 if (!uvm_map_reserve(dstmap, len, start, 0, &dstaddr, 0)) 2297 return (ENOMEM); 2298 *dstaddrp = dstaddr; /* pass address back to caller */ 2299 UVMHIST_LOG(maphist, " dstaddr=0x%x", dstaddr,0,0,0); 2300 } else { 2301 dstaddr = *dstaddrp; 2302 } 2303 2304 /* 2305 * step 2: setup for the extraction process loop by init'ing the 2306 * map entry chain, locking src map, and looking up the first useful 2307 * entry in the map. 2308 */ 2309 2310 end = start + len; 2311 newend = dstaddr + len; 2312 chain = endchain = NULL; 2313 nchain = 0; 2314 vm_map_lock(srcmap); 2315 2316 if (uvm_map_lookup_entry(srcmap, start, &entry)) { 2317 2318 /* "start" is within an entry */ 2319 if (flags & UVM_EXTRACT_QREF) { 2320 2321 /* 2322 * for quick references we don't clip the entry, so 2323 * the entry may map space "before" the starting 2324 * virtual address... this is the "fudge" factor 2325 * (which can be non-zero only the first time 2326 * through the "while" loop in step 3). 2327 */ 2328 2329 fudge = start - entry->start; 2330 } else { 2331 2332 /* 2333 * normal reference: we clip the map to fit (thus 2334 * fudge is zero) 2335 */ 2336 2337 UVM_MAP_CLIP_START(srcmap, entry, start, NULL); 2338 SAVE_HINT(srcmap, srcmap->hint, entry->prev); 2339 fudge = 0; 2340 } 2341 } else { 2342 2343 /* "start" is not within an entry ... skip to next entry */ 2344 if (flags & UVM_EXTRACT_CONTIG) { 2345 error = EINVAL; 2346 goto bad; /* definite hole here ... */ 2347 } 2348 2349 entry = entry->next; 2350 fudge = 0; 2351 } 2352 2353 /* save values from srcmap for step 6 */ 2354 orig_entry = entry; 2355 orig_fudge = fudge; 2356 2357 /* 2358 * step 3: now start looping through the map entries, extracting 2359 * as we go. 2360 */ 2361 2362 while (entry->start < end && entry != &srcmap->header) { 2363 2364 /* if we are not doing a quick reference, clip it */ 2365 if ((flags & UVM_EXTRACT_QREF) == 0) 2366 UVM_MAP_CLIP_END(srcmap, entry, end, NULL); 2367 2368 /* clear needs_copy (allow chunking) */ 2369 if (UVM_ET_ISNEEDSCOPY(entry)) { 2370 amap_copy(srcmap, entry, 2371 AMAP_COPY_NOWAIT|AMAP_COPY_NOMERGE, start, end); 2372 if (UVM_ET_ISNEEDSCOPY(entry)) { /* failed? */ 2373 error = ENOMEM; 2374 goto bad; 2375 } 2376 2377 /* amap_copy could clip (during chunk)! update fudge */ 2378 if (fudge) { 2379 fudge = start - entry->start; 2380 orig_fudge = fudge; 2381 } 2382 } 2383 2384 /* calculate the offset of this from "start" */ 2385 oldoffset = (entry->start + fudge) - start; 2386 2387 /* allocate a new map entry */ 2388 newentry = uvm_mapent_alloc(dstmap, 0); 2389 if (newentry == NULL) { 2390 error = ENOMEM; 2391 goto bad; 2392 } 2393 2394 /* set up new map entry */ 2395 newentry->next = NULL; 2396 newentry->prev = endchain; 2397 newentry->start = dstaddr + oldoffset; 2398 newentry->end = 2399 newentry->start + (entry->end - (entry->start + fudge)); 2400 if (newentry->end > newend || newentry->end < newentry->start) 2401 newentry->end = newend; 2402 newentry->object.uvm_obj = entry->object.uvm_obj; 2403 if (newentry->object.uvm_obj) { 2404 if (newentry->object.uvm_obj->pgops->pgo_reference) 2405 newentry->object.uvm_obj->pgops-> 2406 pgo_reference(newentry->object.uvm_obj); 2407 newentry->offset = entry->offset + fudge; 2408 } else { 2409 newentry->offset = 0; 2410 } 2411 newentry->etype = entry->etype; 2412 newentry->protection = (flags & UVM_EXTRACT_FIXPROT) ? 2413 entry->max_protection : entry->protection; 2414 newentry->max_protection = entry->max_protection; 2415 newentry->inheritance = entry->inheritance; 2416 newentry->wired_count = 0; 2417 newentry->aref.ar_amap = entry->aref.ar_amap; 2418 if (newentry->aref.ar_amap) { 2419 newentry->aref.ar_pageoff = 2420 entry->aref.ar_pageoff + (fudge >> PAGE_SHIFT); 2421 uvm_map_reference_amap(newentry, AMAP_SHARED | 2422 ((flags & UVM_EXTRACT_QREF) ? AMAP_REFALL : 0)); 2423 } else { 2424 newentry->aref.ar_pageoff = 0; 2425 } 2426 newentry->advice = entry->advice; 2427 2428 /* now link it on the chain */ 2429 nchain++; 2430 if (endchain == NULL) { 2431 chain = endchain = newentry; 2432 } else { 2433 endchain->next = newentry; 2434 endchain = newentry; 2435 } 2436 2437 /* end of 'while' loop! */ 2438 if ((flags & UVM_EXTRACT_CONTIG) && entry->end < end && 2439 (entry->next == &srcmap->header || 2440 entry->next->start != entry->end)) { 2441 error = EINVAL; 2442 goto bad; 2443 } 2444 entry = entry->next; 2445 fudge = 0; 2446 } 2447 2448 /* 2449 * step 4: close off chain (in format expected by uvm_map_replace) 2450 */ 2451 2452 if (chain) 2453 chain->prev = endchain; 2454 2455 /* 2456 * step 5: attempt to lock the dest map so we can pmap_copy. 2457 * note usage of copy_ok: 2458 * 1 => dstmap locked, pmap_copy ok, and we "replace" here (step 5) 2459 * 0 => dstmap unlocked, NO pmap_copy, and we will "replace" in step 7 2460 */ 2461 2462 if (srcmap == dstmap || vm_map_lock_try(dstmap) == TRUE) { 2463 copy_ok = 1; 2464 if (!uvm_map_replace(dstmap, dstaddr, dstaddr+len, chain, 2465 nchain)) { 2466 if (srcmap != dstmap) 2467 vm_map_unlock(dstmap); 2468 error = EIO; 2469 goto bad; 2470 } 2471 } else { 2472 copy_ok = 0; 2473 /* replace defered until step 7 */ 2474 } 2475 2476 /* 2477 * step 6: traverse the srcmap a second time to do the following: 2478 * - if we got a lock on the dstmap do pmap_copy 2479 * - if UVM_EXTRACT_REMOVE remove the entries 2480 * we make use of orig_entry and orig_fudge (saved in step 2) 2481 */ 2482 2483 if (copy_ok || (flags & UVM_EXTRACT_REMOVE)) { 2484 2485 /* purge possible stale hints from srcmap */ 2486 if (flags & UVM_EXTRACT_REMOVE) { 2487 SAVE_HINT(srcmap, srcmap->hint, orig_entry->prev); 2488 if (srcmap->first_free->start >= start) 2489 srcmap->first_free = orig_entry->prev; 2490 } 2491 2492 entry = orig_entry; 2493 fudge = orig_fudge; 2494 deadentry = NULL; /* for UVM_EXTRACT_REMOVE */ 2495 2496 while (entry->start < end && entry != &srcmap->header) { 2497 if (copy_ok) { 2498 oldoffset = (entry->start + fudge) - start; 2499 elen = MIN(end, entry->end) - 2500 (entry->start + fudge); 2501 pmap_copy(dstmap->pmap, srcmap->pmap, 2502 dstaddr + oldoffset, elen, 2503 entry->start + fudge); 2504 } 2505 2506 /* we advance "entry" in the following if statement */ 2507 if (flags & UVM_EXTRACT_REMOVE) { 2508 pmap_remove(srcmap->pmap, entry->start, 2509 entry->end); 2510 oldentry = entry; /* save entry */ 2511 entry = entry->next; /* advance */ 2512 uvm_map_entry_unlink(srcmap, oldentry); 2513 /* add to dead list */ 2514 oldentry->next = deadentry; 2515 deadentry = oldentry; 2516 } else { 2517 entry = entry->next; /* advance */ 2518 } 2519 2520 /* end of 'while' loop */ 2521 fudge = 0; 2522 } 2523 pmap_update(srcmap->pmap); 2524 2525 /* 2526 * unlock dstmap. we will dispose of deadentry in 2527 * step 7 if needed 2528 */ 2529 2530 if (copy_ok && srcmap != dstmap) 2531 vm_map_unlock(dstmap); 2532 2533 } else { 2534 deadentry = NULL; 2535 } 2536 2537 /* 2538 * step 7: we are done with the source map, unlock. if copy_ok 2539 * is 0 then we have not replaced the dummy mapping in dstmap yet 2540 * and we need to do so now. 2541 */ 2542 2543 vm_map_unlock(srcmap); 2544 if ((flags & UVM_EXTRACT_REMOVE) && deadentry) 2545 uvm_unmap_detach(deadentry, 0); /* dispose of old entries */ 2546 2547 /* now do the replacement if we didn't do it in step 5 */ 2548 if (copy_ok == 0) { 2549 vm_map_lock(dstmap); 2550 error = uvm_map_replace(dstmap, dstaddr, dstaddr+len, chain, 2551 nchain); 2552 vm_map_unlock(dstmap); 2553 2554 if (error == FALSE) { 2555 error = EIO; 2556 goto bad2; 2557 } 2558 } 2559 2560 uvm_tree_sanity(srcmap, "map_extract src leave"); 2561 uvm_tree_sanity(dstmap, "map_extract dst leave"); 2562 2563 return (0); 2564 2565 /* 2566 * bad: failure recovery 2567 */ 2568 bad: 2569 vm_map_unlock(srcmap); 2570 bad2: /* src already unlocked */ 2571 if (chain) 2572 uvm_unmap_detach(chain, 2573 (flags & UVM_EXTRACT_QREF) ? AMAP_REFALL : 0); 2574 2575 uvm_tree_sanity(srcmap, "map_extract src err leave"); 2576 uvm_tree_sanity(dstmap, "map_extract dst err leave"); 2577 2578 if ((flags & UVM_EXTRACT_RESERVED) == 0) { 2579 uvm_unmap(dstmap, dstaddr, dstaddr+len); /* ??? */ 2580 } 2581 return (error); 2582 } 2583 2584 /* end of extraction functions */ 2585 2586 /* 2587 * uvm_map_submap: punch down part of a map into a submap 2588 * 2589 * => only the kernel_map is allowed to be submapped 2590 * => the purpose of submapping is to break up the locking granularity 2591 * of a larger map 2592 * => the range specified must have been mapped previously with a uvm_map() 2593 * call [with uobj==NULL] to create a blank map entry in the main map. 2594 * [And it had better still be blank!] 2595 * => maps which contain submaps should never be copied or forked. 2596 * => to remove a submap, use uvm_unmap() on the main map 2597 * and then uvm_map_deallocate() the submap. 2598 * => main map must be unlocked. 2599 * => submap must have been init'd and have a zero reference count. 2600 * [need not be locked as we don't actually reference it] 2601 */ 2602 2603 int 2604 uvm_map_submap(struct vm_map *map, vaddr_t start, vaddr_t end, 2605 struct vm_map *submap) 2606 { 2607 struct vm_map_entry *entry; 2608 struct uvm_mapent_reservation umr; 2609 int error; 2610 2611 uvm_mapent_reserve(map, &umr, 2, 0); 2612 2613 vm_map_lock(map); 2614 VM_MAP_RANGE_CHECK(map, start, end); 2615 2616 if (uvm_map_lookup_entry(map, start, &entry)) { 2617 UVM_MAP_CLIP_START(map, entry, start, &umr); 2618 UVM_MAP_CLIP_END(map, entry, end, &umr); /* to be safe */ 2619 } else { 2620 entry = NULL; 2621 } 2622 2623 if (entry != NULL && 2624 entry->start == start && entry->end == end && 2625 entry->object.uvm_obj == NULL && entry->aref.ar_amap == NULL && 2626 !UVM_ET_ISCOPYONWRITE(entry) && !UVM_ET_ISNEEDSCOPY(entry)) { 2627 entry->etype |= UVM_ET_SUBMAP; 2628 entry->object.sub_map = submap; 2629 entry->offset = 0; 2630 uvm_map_reference(submap); 2631 error = 0; 2632 } else { 2633 error = EINVAL; 2634 } 2635 vm_map_unlock(map); 2636 2637 uvm_mapent_unreserve(map, &umr); 2638 2639 return error; 2640 } 2641 2642 /* 2643 * uvm_map_setup_kernel: init in-kernel map 2644 * 2645 * => map must not be in service yet. 2646 */ 2647 2648 void 2649 uvm_map_setup_kernel(struct vm_map_kernel *map, 2650 vaddr_t vmin, vaddr_t vmax, int flags) 2651 { 2652 2653 uvm_map_setup(&map->vmk_map, vmin, vmax, flags); 2654 2655 LIST_INIT(&map->vmk_kentry_free); 2656 map->vmk_merged_entries = NULL; 2657 } 2658 2659 2660 /* 2661 * uvm_map_protect: change map protection 2662 * 2663 * => set_max means set max_protection. 2664 * => map must be unlocked. 2665 */ 2666 2667 #define MASK(entry) (UVM_ET_ISCOPYONWRITE(entry) ? \ 2668 ~VM_PROT_WRITE : VM_PROT_ALL) 2669 2670 int 2671 uvm_map_protect(struct vm_map *map, vaddr_t start, vaddr_t end, 2672 vm_prot_t new_prot, boolean_t set_max) 2673 { 2674 struct vm_map_entry *current, *entry; 2675 int error = 0; 2676 UVMHIST_FUNC("uvm_map_protect"); UVMHIST_CALLED(maphist); 2677 UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,new_prot=0x%x)", 2678 map, start, end, new_prot); 2679 2680 vm_map_lock(map); 2681 VM_MAP_RANGE_CHECK(map, start, end); 2682 if (uvm_map_lookup_entry(map, start, &entry)) { 2683 UVM_MAP_CLIP_START(map, entry, start, NULL); 2684 } else { 2685 entry = entry->next; 2686 } 2687 2688 /* 2689 * make a first pass to check for protection violations. 2690 */ 2691 2692 current = entry; 2693 while ((current != &map->header) && (current->start < end)) { 2694 if (UVM_ET_ISSUBMAP(current)) { 2695 error = EINVAL; 2696 goto out; 2697 } 2698 if ((new_prot & current->max_protection) != new_prot) { 2699 error = EACCES; 2700 goto out; 2701 } 2702 /* 2703 * Don't allow VM_PROT_EXECUTE to be set on entries that 2704 * point to vnodes that are associated with a NOEXEC file 2705 * system. 2706 */ 2707 if (UVM_ET_ISOBJ(current) && 2708 UVM_OBJ_IS_VNODE(current->object.uvm_obj)) { 2709 struct vnode *vp = 2710 (struct vnode *) current->object.uvm_obj; 2711 2712 if ((new_prot & VM_PROT_EXECUTE) != 0 && 2713 (vp->v_mount->mnt_flag & MNT_NOEXEC) != 0) { 2714 error = EACCES; 2715 goto out; 2716 } 2717 } 2718 current = current->next; 2719 } 2720 2721 /* go back and fix up protections (no need to clip this time). */ 2722 2723 current = entry; 2724 while ((current != &map->header) && (current->start < end)) { 2725 vm_prot_t old_prot; 2726 2727 UVM_MAP_CLIP_END(map, current, end, NULL); 2728 old_prot = current->protection; 2729 if (set_max) 2730 current->protection = 2731 (current->max_protection = new_prot) & old_prot; 2732 else 2733 current->protection = new_prot; 2734 2735 /* 2736 * update physical map if necessary. worry about copy-on-write 2737 * here -- CHECK THIS XXX 2738 */ 2739 2740 if (current->protection != old_prot) { 2741 /* update pmap! */ 2742 pmap_protect(map->pmap, current->start, current->end, 2743 current->protection & MASK(entry)); 2744 2745 /* 2746 * If this entry points at a vnode, and the 2747 * protection includes VM_PROT_EXECUTE, mark 2748 * the vnode as VEXECMAP. 2749 */ 2750 if (UVM_ET_ISOBJ(current)) { 2751 struct uvm_object *uobj = 2752 current->object.uvm_obj; 2753 2754 if (UVM_OBJ_IS_VNODE(uobj) && 2755 (current->protection & VM_PROT_EXECUTE)) 2756 vn_markexec((struct vnode *) uobj); 2757 } 2758 } 2759 2760 /* 2761 * If the map is configured to lock any future mappings, 2762 * wire this entry now if the old protection was VM_PROT_NONE 2763 * and the new protection is not VM_PROT_NONE. 2764 */ 2765 2766 if ((map->flags & VM_MAP_WIREFUTURE) != 0 && 2767 VM_MAPENT_ISWIRED(entry) == 0 && 2768 old_prot == VM_PROT_NONE && 2769 new_prot != VM_PROT_NONE) { 2770 if (uvm_map_pageable(map, entry->start, 2771 entry->end, FALSE, 2772 UVM_LK_ENTER|UVM_LK_EXIT) != 0) { 2773 2774 /* 2775 * If locking the entry fails, remember the 2776 * error if it's the first one. Note we 2777 * still continue setting the protection in 2778 * the map, but will return the error 2779 * condition regardless. 2780 * 2781 * XXX Ignore what the actual error is, 2782 * XXX just call it a resource shortage 2783 * XXX so that it doesn't get confused 2784 * XXX what uvm_map_protect() itself would 2785 * XXX normally return. 2786 */ 2787 2788 error = ENOMEM; 2789 } 2790 } 2791 current = current->next; 2792 } 2793 pmap_update(map->pmap); 2794 2795 out: 2796 vm_map_unlock(map); 2797 2798 UVMHIST_LOG(maphist, "<- done, error=%d",error,0,0,0); 2799 return error; 2800 } 2801 2802 #undef MASK 2803 2804 /* 2805 * uvm_map_inherit: set inheritance code for range of addrs in map. 2806 * 2807 * => map must be unlocked 2808 * => note that the inherit code is used during a "fork". see fork 2809 * code for details. 2810 */ 2811 2812 int 2813 uvm_map_inherit(struct vm_map *map, vaddr_t start, vaddr_t end, 2814 vm_inherit_t new_inheritance) 2815 { 2816 struct vm_map_entry *entry, *temp_entry; 2817 UVMHIST_FUNC("uvm_map_inherit"); UVMHIST_CALLED(maphist); 2818 UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,new_inh=0x%x)", 2819 map, start, end, new_inheritance); 2820 2821 switch (new_inheritance) { 2822 case MAP_INHERIT_NONE: 2823 case MAP_INHERIT_COPY: 2824 case MAP_INHERIT_SHARE: 2825 break; 2826 default: 2827 UVMHIST_LOG(maphist,"<- done (INVALID ARG)",0,0,0,0); 2828 return EINVAL; 2829 } 2830 2831 vm_map_lock(map); 2832 VM_MAP_RANGE_CHECK(map, start, end); 2833 if (uvm_map_lookup_entry(map, start, &temp_entry)) { 2834 entry = temp_entry; 2835 UVM_MAP_CLIP_START(map, entry, start, NULL); 2836 } else { 2837 entry = temp_entry->next; 2838 } 2839 while ((entry != &map->header) && (entry->start < end)) { 2840 UVM_MAP_CLIP_END(map, entry, end, NULL); 2841 entry->inheritance = new_inheritance; 2842 entry = entry->next; 2843 } 2844 vm_map_unlock(map); 2845 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 2846 return 0; 2847 } 2848 2849 /* 2850 * uvm_map_advice: set advice code for range of addrs in map. 2851 * 2852 * => map must be unlocked 2853 */ 2854 2855 int 2856 uvm_map_advice(struct vm_map *map, vaddr_t start, vaddr_t end, int new_advice) 2857 { 2858 struct vm_map_entry *entry, *temp_entry; 2859 UVMHIST_FUNC("uvm_map_advice"); UVMHIST_CALLED(maphist); 2860 UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,new_adv=0x%x)", 2861 map, start, end, new_advice); 2862 2863 vm_map_lock(map); 2864 VM_MAP_RANGE_CHECK(map, start, end); 2865 if (uvm_map_lookup_entry(map, start, &temp_entry)) { 2866 entry = temp_entry; 2867 UVM_MAP_CLIP_START(map, entry, start, NULL); 2868 } else { 2869 entry = temp_entry->next; 2870 } 2871 2872 /* 2873 * XXXJRT: disallow holes? 2874 */ 2875 2876 while ((entry != &map->header) && (entry->start < end)) { 2877 UVM_MAP_CLIP_END(map, entry, end, NULL); 2878 2879 switch (new_advice) { 2880 case MADV_NORMAL: 2881 case MADV_RANDOM: 2882 case MADV_SEQUENTIAL: 2883 /* nothing special here */ 2884 break; 2885 2886 default: 2887 vm_map_unlock(map); 2888 UVMHIST_LOG(maphist,"<- done (INVALID ARG)",0,0,0,0); 2889 return EINVAL; 2890 } 2891 entry->advice = new_advice; 2892 entry = entry->next; 2893 } 2894 2895 vm_map_unlock(map); 2896 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 2897 return 0; 2898 } 2899 2900 /* 2901 * uvm_map_pageable: sets the pageability of a range in a map. 2902 * 2903 * => wires map entries. should not be used for transient page locking. 2904 * for that, use uvm_fault_wire()/uvm_fault_unwire() (see uvm_vslock()). 2905 * => regions sepcified as not pageable require lock-down (wired) memory 2906 * and page tables. 2907 * => map must never be read-locked 2908 * => if islocked is TRUE, map is already write-locked 2909 * => we always unlock the map, since we must downgrade to a read-lock 2910 * to call uvm_fault_wire() 2911 * => XXXCDC: check this and try and clean it up. 2912 */ 2913 2914 int 2915 uvm_map_pageable(struct vm_map *map, vaddr_t start, vaddr_t end, 2916 boolean_t new_pageable, int lockflags) 2917 { 2918 struct vm_map_entry *entry, *start_entry, *failed_entry; 2919 int rv; 2920 #ifdef DIAGNOSTIC 2921 u_int timestamp_save; 2922 #endif 2923 UVMHIST_FUNC("uvm_map_pageable"); UVMHIST_CALLED(maphist); 2924 UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,new_pageable=0x%x)", 2925 map, start, end, new_pageable); 2926 KASSERT(map->flags & VM_MAP_PAGEABLE); 2927 2928 if ((lockflags & UVM_LK_ENTER) == 0) 2929 vm_map_lock(map); 2930 VM_MAP_RANGE_CHECK(map, start, end); 2931 2932 /* 2933 * only one pageability change may take place at one time, since 2934 * uvm_fault_wire assumes it will be called only once for each 2935 * wiring/unwiring. therefore, we have to make sure we're actually 2936 * changing the pageability for the entire region. we do so before 2937 * making any changes. 2938 */ 2939 2940 if (uvm_map_lookup_entry(map, start, &start_entry) == FALSE) { 2941 if ((lockflags & UVM_LK_EXIT) == 0) 2942 vm_map_unlock(map); 2943 2944 UVMHIST_LOG(maphist,"<- done (fault)",0,0,0,0); 2945 return EFAULT; 2946 } 2947 entry = start_entry; 2948 2949 /* 2950 * handle wiring and unwiring separately. 2951 */ 2952 2953 if (new_pageable) { /* unwire */ 2954 UVM_MAP_CLIP_START(map, entry, start, NULL); 2955 2956 /* 2957 * unwiring. first ensure that the range to be unwired is 2958 * really wired down and that there are no holes. 2959 */ 2960 2961 while ((entry != &map->header) && (entry->start < end)) { 2962 if (entry->wired_count == 0 || 2963 (entry->end < end && 2964 (entry->next == &map->header || 2965 entry->next->start > entry->end))) { 2966 if ((lockflags & UVM_LK_EXIT) == 0) 2967 vm_map_unlock(map); 2968 UVMHIST_LOG(maphist, "<- done (INVAL)",0,0,0,0); 2969 return EINVAL; 2970 } 2971 entry = entry->next; 2972 } 2973 2974 /* 2975 * POSIX 1003.1b - a single munlock call unlocks a region, 2976 * regardless of the number of mlock calls made on that 2977 * region. 2978 */ 2979 2980 entry = start_entry; 2981 while ((entry != &map->header) && (entry->start < end)) { 2982 UVM_MAP_CLIP_END(map, entry, end, NULL); 2983 if (VM_MAPENT_ISWIRED(entry)) 2984 uvm_map_entry_unwire(map, entry); 2985 entry = entry->next; 2986 } 2987 if ((lockflags & UVM_LK_EXIT) == 0) 2988 vm_map_unlock(map); 2989 UVMHIST_LOG(maphist,"<- done (OK UNWIRE)",0,0,0,0); 2990 return 0; 2991 } 2992 2993 /* 2994 * wire case: in two passes [XXXCDC: ugly block of code here] 2995 * 2996 * 1: holding the write lock, we create any anonymous maps that need 2997 * to be created. then we clip each map entry to the region to 2998 * be wired and increment its wiring count. 2999 * 3000 * 2: we downgrade to a read lock, and call uvm_fault_wire to fault 3001 * in the pages for any newly wired area (wired_count == 1). 3002 * 3003 * downgrading to a read lock for uvm_fault_wire avoids a possible 3004 * deadlock with another thread that may have faulted on one of 3005 * the pages to be wired (it would mark the page busy, blocking 3006 * us, then in turn block on the map lock that we hold). because 3007 * of problems in the recursive lock package, we cannot upgrade 3008 * to a write lock in vm_map_lookup. thus, any actions that 3009 * require the write lock must be done beforehand. because we 3010 * keep the read lock on the map, the copy-on-write status of the 3011 * entries we modify here cannot change. 3012 */ 3013 3014 while ((entry != &map->header) && (entry->start < end)) { 3015 if (VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 3016 3017 /* 3018 * perform actions of vm_map_lookup that need the 3019 * write lock on the map: create an anonymous map 3020 * for a copy-on-write region, or an anonymous map 3021 * for a zero-fill region. (XXXCDC: submap case 3022 * ok?) 3023 */ 3024 3025 if (!UVM_ET_ISSUBMAP(entry)) { /* not submap */ 3026 if (UVM_ET_ISNEEDSCOPY(entry) && 3027 ((entry->max_protection & VM_PROT_WRITE) || 3028 (entry->object.uvm_obj == NULL))) { 3029 amap_copy(map, entry, 0, start, end); 3030 /* XXXCDC: wait OK? */ 3031 } 3032 } 3033 } 3034 UVM_MAP_CLIP_START(map, entry, start, NULL); 3035 UVM_MAP_CLIP_END(map, entry, end, NULL); 3036 entry->wired_count++; 3037 3038 /* 3039 * Check for holes 3040 */ 3041 3042 if (entry->protection == VM_PROT_NONE || 3043 (entry->end < end && 3044 (entry->next == &map->header || 3045 entry->next->start > entry->end))) { 3046 3047 /* 3048 * found one. amap creation actions do not need to 3049 * be undone, but the wired counts need to be restored. 3050 */ 3051 3052 while (entry != &map->header && entry->end > start) { 3053 entry->wired_count--; 3054 entry = entry->prev; 3055 } 3056 if ((lockflags & UVM_LK_EXIT) == 0) 3057 vm_map_unlock(map); 3058 UVMHIST_LOG(maphist,"<- done (INVALID WIRE)",0,0,0,0); 3059 return EINVAL; 3060 } 3061 entry = entry->next; 3062 } 3063 3064 /* 3065 * Pass 2. 3066 */ 3067 3068 #ifdef DIAGNOSTIC 3069 timestamp_save = map->timestamp; 3070 #endif 3071 vm_map_busy(map); 3072 vm_map_downgrade(map); 3073 3074 rv = 0; 3075 entry = start_entry; 3076 while (entry != &map->header && entry->start < end) { 3077 if (entry->wired_count == 1) { 3078 rv = uvm_fault_wire(map, entry->start, entry->end, 3079 VM_FAULT_WIREMAX, entry->max_protection); 3080 if (rv) { 3081 3082 /* 3083 * wiring failed. break out of the loop. 3084 * we'll clean up the map below, once we 3085 * have a write lock again. 3086 */ 3087 3088 break; 3089 } 3090 } 3091 entry = entry->next; 3092 } 3093 3094 if (rv) { /* failed? */ 3095 3096 /* 3097 * Get back to an exclusive (write) lock. 3098 */ 3099 3100 vm_map_upgrade(map); 3101 vm_map_unbusy(map); 3102 3103 #ifdef DIAGNOSTIC 3104 if (timestamp_save != map->timestamp) 3105 panic("uvm_map_pageable: stale map"); 3106 #endif 3107 3108 /* 3109 * first drop the wiring count on all the entries 3110 * which haven't actually been wired yet. 3111 */ 3112 3113 failed_entry = entry; 3114 while (entry != &map->header && entry->start < end) { 3115 entry->wired_count--; 3116 entry = entry->next; 3117 } 3118 3119 /* 3120 * now, unwire all the entries that were successfully 3121 * wired above. 3122 */ 3123 3124 entry = start_entry; 3125 while (entry != failed_entry) { 3126 entry->wired_count--; 3127 if (VM_MAPENT_ISWIRED(entry) == 0) 3128 uvm_map_entry_unwire(map, entry); 3129 entry = entry->next; 3130 } 3131 if ((lockflags & UVM_LK_EXIT) == 0) 3132 vm_map_unlock(map); 3133 UVMHIST_LOG(maphist, "<- done (RV=%d)", rv,0,0,0); 3134 return (rv); 3135 } 3136 3137 /* We are holding a read lock here. */ 3138 if ((lockflags & UVM_LK_EXIT) == 0) { 3139 vm_map_unbusy(map); 3140 vm_map_unlock_read(map); 3141 } else { 3142 3143 /* 3144 * Get back to an exclusive (write) lock. 3145 */ 3146 3147 vm_map_upgrade(map); 3148 vm_map_unbusy(map); 3149 } 3150 3151 UVMHIST_LOG(maphist,"<- done (OK WIRE)",0,0,0,0); 3152 return 0; 3153 } 3154 3155 /* 3156 * uvm_map_pageable_all: special case of uvm_map_pageable - affects 3157 * all mapped regions. 3158 * 3159 * => map must not be locked. 3160 * => if no flags are specified, all regions are unwired. 3161 * => XXXJRT: has some of the same problems as uvm_map_pageable() above. 3162 */ 3163 3164 int 3165 uvm_map_pageable_all(struct vm_map *map, int flags, vsize_t limit) 3166 { 3167 struct vm_map_entry *entry, *failed_entry; 3168 vsize_t size; 3169 int rv; 3170 #ifdef DIAGNOSTIC 3171 u_int timestamp_save; 3172 #endif 3173 UVMHIST_FUNC("uvm_map_pageable_all"); UVMHIST_CALLED(maphist); 3174 UVMHIST_LOG(maphist,"(map=0x%x,flags=0x%x)", map, flags, 0, 0); 3175 3176 KASSERT(map->flags & VM_MAP_PAGEABLE); 3177 3178 vm_map_lock(map); 3179 3180 /* 3181 * handle wiring and unwiring separately. 3182 */ 3183 3184 if (flags == 0) { /* unwire */ 3185 3186 /* 3187 * POSIX 1003.1b -- munlockall unlocks all regions, 3188 * regardless of how many times mlockall has been called. 3189 */ 3190 3191 for (entry = map->header.next; entry != &map->header; 3192 entry = entry->next) { 3193 if (VM_MAPENT_ISWIRED(entry)) 3194 uvm_map_entry_unwire(map, entry); 3195 } 3196 vm_map_modflags(map, 0, VM_MAP_WIREFUTURE); 3197 vm_map_unlock(map); 3198 UVMHIST_LOG(maphist,"<- done (OK UNWIRE)",0,0,0,0); 3199 return 0; 3200 } 3201 3202 if (flags & MCL_FUTURE) { 3203 3204 /* 3205 * must wire all future mappings; remember this. 3206 */ 3207 3208 vm_map_modflags(map, VM_MAP_WIREFUTURE, 0); 3209 } 3210 3211 if ((flags & MCL_CURRENT) == 0) { 3212 3213 /* 3214 * no more work to do! 3215 */ 3216 3217 UVMHIST_LOG(maphist,"<- done (OK no wire)",0,0,0,0); 3218 vm_map_unlock(map); 3219 return 0; 3220 } 3221 3222 /* 3223 * wire case: in three passes [XXXCDC: ugly block of code here] 3224 * 3225 * 1: holding the write lock, count all pages mapped by non-wired 3226 * entries. if this would cause us to go over our limit, we fail. 3227 * 3228 * 2: still holding the write lock, we create any anonymous maps that 3229 * need to be created. then we increment its wiring count. 3230 * 3231 * 3: we downgrade to a read lock, and call uvm_fault_wire to fault 3232 * in the pages for any newly wired area (wired_count == 1). 3233 * 3234 * downgrading to a read lock for uvm_fault_wire avoids a possible 3235 * deadlock with another thread that may have faulted on one of 3236 * the pages to be wired (it would mark the page busy, blocking 3237 * us, then in turn block on the map lock that we hold). because 3238 * of problems in the recursive lock package, we cannot upgrade 3239 * to a write lock in vm_map_lookup. thus, any actions that 3240 * require the write lock must be done beforehand. because we 3241 * keep the read lock on the map, the copy-on-write status of the 3242 * entries we modify here cannot change. 3243 */ 3244 3245 for (size = 0, entry = map->header.next; entry != &map->header; 3246 entry = entry->next) { 3247 if (entry->protection != VM_PROT_NONE && 3248 VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 3249 size += entry->end - entry->start; 3250 } 3251 } 3252 3253 if (atop(size) + uvmexp.wired > uvmexp.wiredmax) { 3254 vm_map_unlock(map); 3255 return ENOMEM; 3256 } 3257 3258 if (limit != 0 && 3259 (size + ptoa(pmap_wired_count(vm_map_pmap(map))) > limit)) { 3260 vm_map_unlock(map); 3261 return ENOMEM; 3262 } 3263 3264 /* 3265 * Pass 2. 3266 */ 3267 3268 for (entry = map->header.next; entry != &map->header; 3269 entry = entry->next) { 3270 if (entry->protection == VM_PROT_NONE) 3271 continue; 3272 if (VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 3273 3274 /* 3275 * perform actions of vm_map_lookup that need the 3276 * write lock on the map: create an anonymous map 3277 * for a copy-on-write region, or an anonymous map 3278 * for a zero-fill region. (XXXCDC: submap case 3279 * ok?) 3280 */ 3281 3282 if (!UVM_ET_ISSUBMAP(entry)) { /* not submap */ 3283 if (UVM_ET_ISNEEDSCOPY(entry) && 3284 ((entry->max_protection & VM_PROT_WRITE) || 3285 (entry->object.uvm_obj == NULL))) { 3286 amap_copy(map, entry, 0, entry->start, 3287 entry->end); 3288 /* XXXCDC: wait OK? */ 3289 } 3290 } 3291 } 3292 entry->wired_count++; 3293 } 3294 3295 /* 3296 * Pass 3. 3297 */ 3298 3299 #ifdef DIAGNOSTIC 3300 timestamp_save = map->timestamp; 3301 #endif 3302 vm_map_busy(map); 3303 vm_map_downgrade(map); 3304 3305 rv = 0; 3306 for (entry = map->header.next; entry != &map->header; 3307 entry = entry->next) { 3308 if (entry->wired_count == 1) { 3309 rv = uvm_fault_wire(map, entry->start, entry->end, 3310 VM_FAULT_WIREMAX, entry->max_protection); 3311 if (rv) { 3312 3313 /* 3314 * wiring failed. break out of the loop. 3315 * we'll clean up the map below, once we 3316 * have a write lock again. 3317 */ 3318 3319 break; 3320 } 3321 } 3322 } 3323 3324 if (rv) { 3325 3326 /* 3327 * Get back an exclusive (write) lock. 3328 */ 3329 3330 vm_map_upgrade(map); 3331 vm_map_unbusy(map); 3332 3333 #ifdef DIAGNOSTIC 3334 if (timestamp_save != map->timestamp) 3335 panic("uvm_map_pageable_all: stale map"); 3336 #endif 3337 3338 /* 3339 * first drop the wiring count on all the entries 3340 * which haven't actually been wired yet. 3341 * 3342 * Skip VM_PROT_NONE entries like we did above. 3343 */ 3344 3345 failed_entry = entry; 3346 for (/* nothing */; entry != &map->header; 3347 entry = entry->next) { 3348 if (entry->protection == VM_PROT_NONE) 3349 continue; 3350 entry->wired_count--; 3351 } 3352 3353 /* 3354 * now, unwire all the entries that were successfully 3355 * wired above. 3356 * 3357 * Skip VM_PROT_NONE entries like we did above. 3358 */ 3359 3360 for (entry = map->header.next; entry != failed_entry; 3361 entry = entry->next) { 3362 if (entry->protection == VM_PROT_NONE) 3363 continue; 3364 entry->wired_count--; 3365 if (VM_MAPENT_ISWIRED(entry)) 3366 uvm_map_entry_unwire(map, entry); 3367 } 3368 vm_map_unlock(map); 3369 UVMHIST_LOG(maphist,"<- done (RV=%d)", rv,0,0,0); 3370 return (rv); 3371 } 3372 3373 /* We are holding a read lock here. */ 3374 vm_map_unbusy(map); 3375 vm_map_unlock_read(map); 3376 3377 UVMHIST_LOG(maphist,"<- done (OK WIRE)",0,0,0,0); 3378 return 0; 3379 } 3380 3381 /* 3382 * uvm_map_clean: clean out a map range 3383 * 3384 * => valid flags: 3385 * if (flags & PGO_CLEANIT): dirty pages are cleaned first 3386 * if (flags & PGO_SYNCIO): dirty pages are written synchronously 3387 * if (flags & PGO_DEACTIVATE): any cached pages are deactivated after clean 3388 * if (flags & PGO_FREE): any cached pages are freed after clean 3389 * => returns an error if any part of the specified range isn't mapped 3390 * => never a need to flush amap layer since the anonymous memory has 3391 * no permanent home, but may deactivate pages there 3392 * => called from sys_msync() and sys_madvise() 3393 * => caller must not write-lock map (read OK). 3394 * => we may sleep while cleaning if SYNCIO [with map read-locked] 3395 */ 3396 3397 int 3398 uvm_map_clean(struct vm_map *map, vaddr_t start, vaddr_t end, int flags) 3399 { 3400 struct vm_map_entry *current, *entry; 3401 struct uvm_object *uobj; 3402 struct vm_amap *amap; 3403 struct vm_anon *anon; 3404 struct vm_page *pg; 3405 vaddr_t offset; 3406 vsize_t size; 3407 voff_t uoff; 3408 int error, refs; 3409 UVMHIST_FUNC("uvm_map_clean"); UVMHIST_CALLED(maphist); 3410 3411 UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,flags=0x%x)", 3412 map, start, end, flags); 3413 KASSERT((flags & (PGO_FREE|PGO_DEACTIVATE)) != 3414 (PGO_FREE|PGO_DEACTIVATE)); 3415 3416 vm_map_lock_read(map); 3417 VM_MAP_RANGE_CHECK(map, start, end); 3418 if (uvm_map_lookup_entry(map, start, &entry) == FALSE) { 3419 vm_map_unlock_read(map); 3420 return EFAULT; 3421 } 3422 3423 /* 3424 * Make a first pass to check for holes and wiring problems. 3425 */ 3426 3427 for (current = entry; current->start < end; current = current->next) { 3428 if (UVM_ET_ISSUBMAP(current)) { 3429 vm_map_unlock_read(map); 3430 return EINVAL; 3431 } 3432 if ((flags & PGO_FREE) != 0 && VM_MAPENT_ISWIRED(entry)) { 3433 vm_map_unlock_read(map); 3434 return EBUSY; 3435 } 3436 if (end <= current->end) { 3437 break; 3438 } 3439 if (current->end != current->next->start) { 3440 vm_map_unlock_read(map); 3441 return EFAULT; 3442 } 3443 } 3444 3445 error = 0; 3446 for (current = entry; start < end; current = current->next) { 3447 amap = current->aref.ar_amap; /* top layer */ 3448 uobj = current->object.uvm_obj; /* bottom layer */ 3449 KASSERT(start >= current->start); 3450 3451 /* 3452 * No amap cleaning necessary if: 3453 * 3454 * (1) There's no amap. 3455 * 3456 * (2) We're not deactivating or freeing pages. 3457 */ 3458 3459 if (amap == NULL || (flags & (PGO_DEACTIVATE|PGO_FREE)) == 0) 3460 goto flush_object; 3461 3462 amap_lock(amap); 3463 offset = start - current->start; 3464 size = MIN(end, current->end) - start; 3465 for ( ; size != 0; size -= PAGE_SIZE, offset += PAGE_SIZE) { 3466 anon = amap_lookup(¤t->aref, offset); 3467 if (anon == NULL) 3468 continue; 3469 3470 simple_lock(&anon->an_lock); 3471 pg = anon->an_page; 3472 if (pg == NULL) { 3473 simple_unlock(&anon->an_lock); 3474 continue; 3475 } 3476 3477 switch (flags & (PGO_CLEANIT|PGO_FREE|PGO_DEACTIVATE)) { 3478 3479 /* 3480 * In these first 3 cases, we just deactivate the page. 3481 */ 3482 3483 case PGO_CLEANIT|PGO_FREE: 3484 case PGO_CLEANIT|PGO_DEACTIVATE: 3485 case PGO_DEACTIVATE: 3486 deactivate_it: 3487 /* 3488 * skip the page if it's loaned or wired, 3489 * since it shouldn't be on a paging queue 3490 * at all in these cases. 3491 */ 3492 3493 uvm_lock_pageq(); 3494 if (pg->loan_count != 0 || 3495 pg->wire_count != 0) { 3496 uvm_unlock_pageq(); 3497 simple_unlock(&anon->an_lock); 3498 continue; 3499 } 3500 KASSERT(pg->uanon == anon); 3501 pmap_clear_reference(pg); 3502 uvm_pagedeactivate(pg); 3503 uvm_unlock_pageq(); 3504 simple_unlock(&anon->an_lock); 3505 continue; 3506 3507 case PGO_FREE: 3508 3509 /* 3510 * If there are multiple references to 3511 * the amap, just deactivate the page. 3512 */ 3513 3514 if (amap_refs(amap) > 1) 3515 goto deactivate_it; 3516 3517 /* skip the page if it's wired */ 3518 if (pg->wire_count != 0) { 3519 simple_unlock(&anon->an_lock); 3520 continue; 3521 } 3522 amap_unadd(¤t->aref, offset); 3523 refs = --anon->an_ref; 3524 simple_unlock(&anon->an_lock); 3525 if (refs == 0) 3526 uvm_anfree(anon); 3527 continue; 3528 } 3529 } 3530 amap_unlock(amap); 3531 3532 flush_object: 3533 /* 3534 * flush pages if we've got a valid backing object. 3535 * note that we must always clean object pages before 3536 * freeing them since otherwise we could reveal stale 3537 * data from files. 3538 */ 3539 3540 uoff = current->offset + (start - current->start); 3541 size = MIN(end, current->end) - start; 3542 if (uobj != NULL) { 3543 simple_lock(&uobj->vmobjlock); 3544 if (uobj->pgops->pgo_put != NULL) 3545 error = (uobj->pgops->pgo_put)(uobj, uoff, 3546 uoff + size, flags | PGO_CLEANIT); 3547 else 3548 error = 0; 3549 } 3550 start += size; 3551 } 3552 vm_map_unlock_read(map); 3553 return (error); 3554 } 3555 3556 3557 /* 3558 * uvm_map_checkprot: check protection in map 3559 * 3560 * => must allow specified protection in a fully allocated region. 3561 * => map must be read or write locked by caller. 3562 */ 3563 3564 boolean_t 3565 uvm_map_checkprot(struct vm_map *map, vaddr_t start, vaddr_t end, 3566 vm_prot_t protection) 3567 { 3568 struct vm_map_entry *entry; 3569 struct vm_map_entry *tmp_entry; 3570 3571 if (!uvm_map_lookup_entry(map, start, &tmp_entry)) { 3572 return (FALSE); 3573 } 3574 entry = tmp_entry; 3575 while (start < end) { 3576 if (entry == &map->header) { 3577 return (FALSE); 3578 } 3579 3580 /* 3581 * no holes allowed 3582 */ 3583 3584 if (start < entry->start) { 3585 return (FALSE); 3586 } 3587 3588 /* 3589 * check protection associated with entry 3590 */ 3591 3592 if ((entry->protection & protection) != protection) { 3593 return (FALSE); 3594 } 3595 start = entry->end; 3596 entry = entry->next; 3597 } 3598 return (TRUE); 3599 } 3600 3601 /* 3602 * uvmspace_alloc: allocate a vmspace structure. 3603 * 3604 * - structure includes vm_map and pmap 3605 * - XXX: no locking on this structure 3606 * - refcnt set to 1, rest must be init'd by caller 3607 */ 3608 struct vmspace * 3609 uvmspace_alloc(vaddr_t vmin, vaddr_t vmax) 3610 { 3611 struct vmspace *vm; 3612 UVMHIST_FUNC("uvmspace_alloc"); UVMHIST_CALLED(maphist); 3613 3614 vm = pool_get(&uvm_vmspace_pool, PR_WAITOK); 3615 uvmspace_init(vm, NULL, vmin, vmax); 3616 UVMHIST_LOG(maphist,"<- done (vm=0x%x)", vm,0,0,0); 3617 return (vm); 3618 } 3619 3620 /* 3621 * uvmspace_init: initialize a vmspace structure. 3622 * 3623 * - XXX: no locking on this structure 3624 * - refcnt set to 1, rest must be init'd by caller 3625 */ 3626 void 3627 uvmspace_init(struct vmspace *vm, struct pmap *pmap, vaddr_t vmin, vaddr_t vmax) 3628 { 3629 UVMHIST_FUNC("uvmspace_init"); UVMHIST_CALLED(maphist); 3630 3631 memset(vm, 0, sizeof(*vm)); 3632 uvm_map_setup(&vm->vm_map, vmin, vmax, VM_MAP_PAGEABLE 3633 #ifdef __USING_TOPDOWN_VM 3634 | VM_MAP_TOPDOWN 3635 #endif 3636 ); 3637 if (pmap) 3638 pmap_reference(pmap); 3639 else 3640 pmap = pmap_create(); 3641 vm->vm_map.pmap = pmap; 3642 vm->vm_refcnt = 1; 3643 UVMHIST_LOG(maphist,"<- done",0,0,0,0); 3644 } 3645 3646 /* 3647 * uvmspace_share: share a vmspace between two processes 3648 * 3649 * - used for vfork, threads(?) 3650 */ 3651 3652 void 3653 uvmspace_share(struct proc *p1, struct proc *p2) 3654 { 3655 3656 uvmspace_addref(p1->p_vmspace); 3657 p2->p_vmspace = p1->p_vmspace; 3658 } 3659 3660 /* 3661 * uvmspace_unshare: ensure that process "p" has its own, unshared, vmspace 3662 * 3663 * - XXX: no locking on vmspace 3664 */ 3665 3666 void 3667 uvmspace_unshare(struct lwp *l) 3668 { 3669 struct proc *p = l->l_proc; 3670 struct vmspace *nvm, *ovm = p->p_vmspace; 3671 3672 if (ovm->vm_refcnt == 1) 3673 /* nothing to do: vmspace isn't shared in the first place */ 3674 return; 3675 3676 /* make a new vmspace, still holding old one */ 3677 nvm = uvmspace_fork(ovm); 3678 3679 pmap_deactivate(l); /* unbind old vmspace */ 3680 p->p_vmspace = nvm; 3681 pmap_activate(l); /* switch to new vmspace */ 3682 3683 uvmspace_free(ovm); /* drop reference to old vmspace */ 3684 } 3685 3686 /* 3687 * uvmspace_exec: the process wants to exec a new program 3688 */ 3689 3690 void 3691 uvmspace_exec(struct lwp *l, vaddr_t start, vaddr_t end) 3692 { 3693 struct proc *p = l->l_proc; 3694 struct vmspace *nvm, *ovm = p->p_vmspace; 3695 struct vm_map *map = &ovm->vm_map; 3696 3697 #ifdef __sparc__ 3698 /* XXX cgd 960926: the sparc #ifdef should be a MD hook */ 3699 kill_user_windows(l); /* before stack addresses go away */ 3700 #endif 3701 3702 /* 3703 * see if more than one process is using this vmspace... 3704 */ 3705 3706 if (ovm->vm_refcnt == 1) { 3707 3708 /* 3709 * if p is the only process using its vmspace then we can safely 3710 * recycle that vmspace for the program that is being exec'd. 3711 */ 3712 3713 #ifdef SYSVSHM 3714 /* 3715 * SYSV SHM semantics require us to kill all segments on an exec 3716 */ 3717 3718 if (ovm->vm_shm) 3719 shmexit(ovm); 3720 #endif 3721 3722 /* 3723 * POSIX 1003.1b -- "lock future mappings" is revoked 3724 * when a process execs another program image. 3725 */ 3726 3727 vm_map_modflags(map, 0, VM_MAP_WIREFUTURE); 3728 3729 /* 3730 * now unmap the old program 3731 */ 3732 3733 pmap_remove_all(map->pmap); 3734 uvm_unmap(map, vm_map_min(map), vm_map_max(map)); 3735 KASSERT(map->header.prev == &map->header); 3736 KASSERT(map->nentries == 0); 3737 3738 /* 3739 * resize the map 3740 */ 3741 3742 vm_map_setmin(map, start); 3743 vm_map_setmax(map, end); 3744 } else { 3745 3746 /* 3747 * p's vmspace is being shared, so we can't reuse it for p since 3748 * it is still being used for others. allocate a new vmspace 3749 * for p 3750 */ 3751 3752 nvm = uvmspace_alloc(start, end); 3753 3754 /* 3755 * install new vmspace and drop our ref to the old one. 3756 */ 3757 3758 pmap_deactivate(l); 3759 p->p_vmspace = nvm; 3760 pmap_activate(l); 3761 3762 uvmspace_free(ovm); 3763 } 3764 } 3765 3766 /* 3767 * uvmspace_addref: add a referece to a vmspace. 3768 */ 3769 3770 void 3771 uvmspace_addref(struct vmspace *vm) 3772 { 3773 struct vm_map *map = &vm->vm_map; 3774 3775 KASSERT((map->flags & VM_MAP_DYING) == 0); 3776 3777 simple_lock(&map->ref_lock); 3778 KASSERT(vm->vm_refcnt > 0); 3779 vm->vm_refcnt++; 3780 simple_unlock(&map->ref_lock); 3781 } 3782 3783 /* 3784 * uvmspace_free: free a vmspace data structure 3785 */ 3786 3787 void 3788 uvmspace_free(struct vmspace *vm) 3789 { 3790 struct vm_map_entry *dead_entries; 3791 struct vm_map *map = &vm->vm_map; 3792 int n; 3793 3794 UVMHIST_FUNC("uvmspace_free"); UVMHIST_CALLED(maphist); 3795 3796 UVMHIST_LOG(maphist,"(vm=0x%x) ref=%d", vm, vm->vm_refcnt,0,0); 3797 simple_lock(&map->ref_lock); 3798 n = --vm->vm_refcnt; 3799 simple_unlock(&map->ref_lock); 3800 if (n > 0) 3801 return; 3802 3803 /* 3804 * at this point, there should be no other references to the map. 3805 * delete all of the mappings, then destroy the pmap. 3806 */ 3807 3808 map->flags |= VM_MAP_DYING; 3809 pmap_remove_all(map->pmap); 3810 #ifdef SYSVSHM 3811 /* Get rid of any SYSV shared memory segments. */ 3812 if (vm->vm_shm != NULL) 3813 shmexit(vm); 3814 #endif 3815 if (map->nentries) { 3816 uvm_unmap_remove(map, vm_map_min(map), vm_map_max(map), 3817 &dead_entries, NULL, 0); 3818 if (dead_entries != NULL) 3819 uvm_unmap_detach(dead_entries, 0); 3820 } 3821 KASSERT(map->nentries == 0); 3822 KASSERT(map->size == 0); 3823 pmap_destroy(map->pmap); 3824 pool_put(&uvm_vmspace_pool, vm); 3825 } 3826 3827 /* 3828 * F O R K - m a i n e n t r y p o i n t 3829 */ 3830 /* 3831 * uvmspace_fork: fork a process' main map 3832 * 3833 * => create a new vmspace for child process from parent. 3834 * => parent's map must not be locked. 3835 */ 3836 3837 struct vmspace * 3838 uvmspace_fork(struct vmspace *vm1) 3839 { 3840 struct vmspace *vm2; 3841 struct vm_map *old_map = &vm1->vm_map; 3842 struct vm_map *new_map; 3843 struct vm_map_entry *old_entry; 3844 struct vm_map_entry *new_entry; 3845 UVMHIST_FUNC("uvmspace_fork"); UVMHIST_CALLED(maphist); 3846 3847 vm_map_lock(old_map); 3848 3849 vm2 = uvmspace_alloc(vm_map_min(old_map), vm_map_max(old_map)); 3850 memcpy(&vm2->vm_startcopy, &vm1->vm_startcopy, 3851 (caddr_t) (vm1 + 1) - (caddr_t) &vm1->vm_startcopy); 3852 new_map = &vm2->vm_map; /* XXX */ 3853 3854 old_entry = old_map->header.next; 3855 new_map->size = old_map->size; 3856 3857 /* 3858 * go entry-by-entry 3859 */ 3860 3861 while (old_entry != &old_map->header) { 3862 3863 /* 3864 * first, some sanity checks on the old entry 3865 */ 3866 3867 KASSERT(!UVM_ET_ISSUBMAP(old_entry)); 3868 KASSERT(UVM_ET_ISCOPYONWRITE(old_entry) || 3869 !UVM_ET_ISNEEDSCOPY(old_entry)); 3870 3871 switch (old_entry->inheritance) { 3872 case MAP_INHERIT_NONE: 3873 3874 /* 3875 * drop the mapping, modify size 3876 */ 3877 new_map->size -= old_entry->end - old_entry->start; 3878 break; 3879 3880 case MAP_INHERIT_SHARE: 3881 3882 /* 3883 * share the mapping: this means we want the old and 3884 * new entries to share amaps and backing objects. 3885 */ 3886 /* 3887 * if the old_entry needs a new amap (due to prev fork) 3888 * then we need to allocate it now so that we have 3889 * something we own to share with the new_entry. [in 3890 * other words, we need to clear needs_copy] 3891 */ 3892 3893 if (UVM_ET_ISNEEDSCOPY(old_entry)) { 3894 /* get our own amap, clears needs_copy */ 3895 amap_copy(old_map, old_entry, AMAP_COPY_NOCHUNK, 3896 0, 0); 3897 /* XXXCDC: WAITOK??? */ 3898 } 3899 3900 new_entry = uvm_mapent_alloc(new_map, 0); 3901 /* old_entry -> new_entry */ 3902 uvm_mapent_copy(old_entry, new_entry); 3903 3904 /* new pmap has nothing wired in it */ 3905 new_entry->wired_count = 0; 3906 3907 /* 3908 * gain reference to object backing the map (can't 3909 * be a submap, already checked this case). 3910 */ 3911 3912 if (new_entry->aref.ar_amap) 3913 uvm_map_reference_amap(new_entry, AMAP_SHARED); 3914 3915 if (new_entry->object.uvm_obj && 3916 new_entry->object.uvm_obj->pgops->pgo_reference) 3917 new_entry->object.uvm_obj-> 3918 pgops->pgo_reference( 3919 new_entry->object.uvm_obj); 3920 3921 /* insert entry at end of new_map's entry list */ 3922 uvm_map_entry_link(new_map, new_map->header.prev, 3923 new_entry); 3924 3925 break; 3926 3927 case MAP_INHERIT_COPY: 3928 3929 /* 3930 * copy-on-write the mapping (using mmap's 3931 * MAP_PRIVATE semantics) 3932 * 3933 * allocate new_entry, adjust reference counts. 3934 * (note that new references are read-only). 3935 */ 3936 3937 new_entry = uvm_mapent_alloc(new_map, 0); 3938 /* old_entry -> new_entry */ 3939 uvm_mapent_copy(old_entry, new_entry); 3940 3941 if (new_entry->aref.ar_amap) 3942 uvm_map_reference_amap(new_entry, 0); 3943 3944 if (new_entry->object.uvm_obj && 3945 new_entry->object.uvm_obj->pgops->pgo_reference) 3946 new_entry->object.uvm_obj->pgops->pgo_reference 3947 (new_entry->object.uvm_obj); 3948 3949 /* new pmap has nothing wired in it */ 3950 new_entry->wired_count = 0; 3951 3952 new_entry->etype |= 3953 (UVM_ET_COPYONWRITE|UVM_ET_NEEDSCOPY); 3954 uvm_map_entry_link(new_map, new_map->header.prev, 3955 new_entry); 3956 3957 /* 3958 * the new entry will need an amap. it will either 3959 * need to be copied from the old entry or created 3960 * from scratch (if the old entry does not have an 3961 * amap). can we defer this process until later 3962 * (by setting "needs_copy") or do we need to copy 3963 * the amap now? 3964 * 3965 * we must copy the amap now if any of the following 3966 * conditions hold: 3967 * 1. the old entry has an amap and that amap is 3968 * being shared. this means that the old (parent) 3969 * process is sharing the amap with another 3970 * process. if we do not clear needs_copy here 3971 * we will end up in a situation where both the 3972 * parent and child process are refering to the 3973 * same amap with "needs_copy" set. if the 3974 * parent write-faults, the fault routine will 3975 * clear "needs_copy" in the parent by allocating 3976 * a new amap. this is wrong because the 3977 * parent is supposed to be sharing the old amap 3978 * and the new amap will break that. 3979 * 3980 * 2. if the old entry has an amap and a non-zero 3981 * wire count then we are going to have to call 3982 * amap_cow_now to avoid page faults in the 3983 * parent process. since amap_cow_now requires 3984 * "needs_copy" to be clear we might as well 3985 * clear it here as well. 3986 * 3987 */ 3988 3989 if (old_entry->aref.ar_amap != NULL) { 3990 if ((amap_flags(old_entry->aref.ar_amap) & 3991 AMAP_SHARED) != 0 || 3992 VM_MAPENT_ISWIRED(old_entry)) { 3993 3994 amap_copy(new_map, new_entry, 3995 AMAP_COPY_NOCHUNK, 0, 0); 3996 /* XXXCDC: M_WAITOK ... ok? */ 3997 } 3998 } 3999 4000 /* 4001 * if the parent's entry is wired down, then the 4002 * parent process does not want page faults on 4003 * access to that memory. this means that we 4004 * cannot do copy-on-write because we can't write 4005 * protect the old entry. in this case we 4006 * resolve all copy-on-write faults now, using 4007 * amap_cow_now. note that we have already 4008 * allocated any needed amap (above). 4009 */ 4010 4011 if (VM_MAPENT_ISWIRED(old_entry)) { 4012 4013 /* 4014 * resolve all copy-on-write faults now 4015 * (note that there is nothing to do if 4016 * the old mapping does not have an amap). 4017 */ 4018 if (old_entry->aref.ar_amap) 4019 amap_cow_now(new_map, new_entry); 4020 4021 } else { 4022 4023 /* 4024 * setup mappings to trigger copy-on-write faults 4025 * we must write-protect the parent if it has 4026 * an amap and it is not already "needs_copy"... 4027 * if it is already "needs_copy" then the parent 4028 * has already been write-protected by a previous 4029 * fork operation. 4030 */ 4031 4032 if (old_entry->aref.ar_amap && 4033 !UVM_ET_ISNEEDSCOPY(old_entry)) { 4034 if (old_entry->max_protection & VM_PROT_WRITE) { 4035 pmap_protect(old_map->pmap, 4036 old_entry->start, 4037 old_entry->end, 4038 old_entry->protection & 4039 ~VM_PROT_WRITE); 4040 pmap_update(old_map->pmap); 4041 } 4042 old_entry->etype |= UVM_ET_NEEDSCOPY; 4043 } 4044 } 4045 break; 4046 } /* end of switch statement */ 4047 old_entry = old_entry->next; 4048 } 4049 4050 vm_map_unlock(old_map); 4051 4052 #ifdef SYSVSHM 4053 if (vm1->vm_shm) 4054 shmfork(vm1, vm2); 4055 #endif 4056 4057 #ifdef PMAP_FORK 4058 pmap_fork(vm1->vm_map.pmap, vm2->vm_map.pmap); 4059 #endif 4060 4061 UVMHIST_LOG(maphist,"<- done",0,0,0,0); 4062 return (vm2); 4063 } 4064 4065 4066 /* 4067 * in-kernel map entry allocation. 4068 */ 4069 4070 struct uvm_kmapent_hdr { 4071 LIST_ENTRY(uvm_kmapent_hdr) ukh_listq; 4072 int ukh_nused; 4073 struct vm_map_entry *ukh_freelist; 4074 struct vm_map *ukh_map; 4075 struct vm_map_entry ukh_entries[0]; 4076 }; 4077 4078 #define UVM_KMAPENT_CHUNK \ 4079 ((PAGE_SIZE - sizeof(struct uvm_kmapent_hdr)) \ 4080 / sizeof(struct vm_map_entry)) 4081 4082 #define UVM_KHDR_FIND(entry) \ 4083 ((struct uvm_kmapent_hdr *)(((vaddr_t)entry) & ~PAGE_MASK)) 4084 4085 4086 #ifdef DIAGNOSTIC 4087 static struct vm_map * 4088 uvm_kmapent_map(struct vm_map_entry *entry) 4089 { 4090 const struct uvm_kmapent_hdr *ukh; 4091 4092 ukh = UVM_KHDR_FIND(entry); 4093 return ukh->ukh_map; 4094 } 4095 #endif 4096 4097 static inline struct vm_map_entry * 4098 uvm_kmapent_get(struct uvm_kmapent_hdr *ukh) 4099 { 4100 struct vm_map_entry *entry; 4101 4102 KASSERT(ukh->ukh_nused <= UVM_KMAPENT_CHUNK); 4103 KASSERT(ukh->ukh_nused >= 0); 4104 4105 entry = ukh->ukh_freelist; 4106 if (entry) { 4107 KASSERT((entry->flags & (UVM_MAP_KERNEL | UVM_MAP_KMAPENT)) 4108 == UVM_MAP_KERNEL); 4109 ukh->ukh_freelist = entry->next; 4110 ukh->ukh_nused++; 4111 KASSERT(ukh->ukh_nused <= UVM_KMAPENT_CHUNK); 4112 } else { 4113 KASSERT(ukh->ukh_nused == UVM_KMAPENT_CHUNK); 4114 } 4115 4116 return entry; 4117 } 4118 4119 static inline void 4120 uvm_kmapent_put(struct uvm_kmapent_hdr *ukh, struct vm_map_entry *entry) 4121 { 4122 4123 KASSERT((entry->flags & (UVM_MAP_KERNEL | UVM_MAP_KMAPENT)) 4124 == UVM_MAP_KERNEL); 4125 KASSERT(ukh->ukh_nused <= UVM_KMAPENT_CHUNK); 4126 KASSERT(ukh->ukh_nused > 0); 4127 KASSERT(ukh->ukh_freelist != NULL || 4128 ukh->ukh_nused == UVM_KMAPENT_CHUNK); 4129 KASSERT(ukh->ukh_freelist == NULL || 4130 ukh->ukh_nused < UVM_KMAPENT_CHUNK); 4131 4132 ukh->ukh_nused--; 4133 entry->next = ukh->ukh_freelist; 4134 ukh->ukh_freelist = entry; 4135 } 4136 4137 /* 4138 * uvm_kmapent_alloc: allocate a map entry for in-kernel map 4139 */ 4140 4141 static struct vm_map_entry * 4142 uvm_kmapent_alloc(struct vm_map *map, int flags) 4143 { 4144 struct vm_page *pg; 4145 struct uvm_map_args args; 4146 struct uvm_kmapent_hdr *ukh; 4147 struct vm_map_entry *entry; 4148 uvm_flag_t mapflags = UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, 4149 UVM_INH_NONE, UVM_ADV_RANDOM, flags | UVM_FLAG_NOMERGE); 4150 vaddr_t va; 4151 int error; 4152 int i; 4153 int s; 4154 4155 KDASSERT(UVM_KMAPENT_CHUNK > 2); 4156 KDASSERT(kernel_map != NULL); 4157 KASSERT(vm_map_pmap(map) == pmap_kernel()); 4158 4159 UVMMAP_EVCNT_INCR(uke_alloc); 4160 entry = NULL; 4161 again: 4162 /* 4163 * try to grab an entry from freelist. 4164 */ 4165 s = splvm(); 4166 simple_lock(&uvm.kentry_lock); 4167 ukh = LIST_FIRST(&vm_map_to_kernel(map)->vmk_kentry_free); 4168 if (ukh) { 4169 entry = uvm_kmapent_get(ukh); 4170 if (ukh->ukh_nused == UVM_KMAPENT_CHUNK) 4171 LIST_REMOVE(ukh, ukh_listq); 4172 } 4173 simple_unlock(&uvm.kentry_lock); 4174 splx(s); 4175 4176 if (entry) 4177 return entry; 4178 4179 /* 4180 * there's no free entry for this vm_map. 4181 * now we need to allocate some vm_map_entry. 4182 * for simplicity, always allocate one page chunk of them at once. 4183 */ 4184 4185 pg = uvm_pagealloc(NULL, 0, NULL, 0); 4186 if (__predict_false(pg == NULL)) { 4187 if (flags & UVM_FLAG_NOWAIT) 4188 return NULL; 4189 uvm_wait("kme_alloc"); 4190 goto again; 4191 } 4192 4193 error = uvm_map_prepare(map, 0, PAGE_SIZE, NULL, 0, 0, mapflags, &args); 4194 if (error) { 4195 uvm_pagefree(pg); 4196 return NULL; 4197 } 4198 4199 va = args.uma_start; 4200 4201 pmap_kenter_pa(va, VM_PAGE_TO_PHYS(pg), VM_PROT_READ|VM_PROT_WRITE); 4202 pmap_update(vm_map_pmap(map)); 4203 4204 ukh = (void *)va; 4205 4206 /* 4207 * use the first entry for ukh itsself. 4208 */ 4209 4210 entry = &ukh->ukh_entries[0]; 4211 entry->flags = UVM_MAP_KERNEL | UVM_MAP_KMAPENT; 4212 error = uvm_map_enter(map, &args, entry); 4213 KASSERT(error == 0); 4214 4215 ukh->ukh_nused = UVM_KMAPENT_CHUNK; 4216 ukh->ukh_map = map; 4217 ukh->ukh_freelist = NULL; 4218 for (i = UVM_KMAPENT_CHUNK - 1; i >= 2; i--) { 4219 struct vm_map_entry *xentry = &ukh->ukh_entries[i]; 4220 4221 xentry->flags = UVM_MAP_KERNEL; 4222 uvm_kmapent_put(ukh, xentry); 4223 } 4224 KASSERT(ukh->ukh_nused == 2); 4225 4226 s = splvm(); 4227 simple_lock(&uvm.kentry_lock); 4228 LIST_INSERT_HEAD(&vm_map_to_kernel(map)->vmk_kentry_free, 4229 ukh, ukh_listq); 4230 simple_unlock(&uvm.kentry_lock); 4231 splx(s); 4232 4233 /* 4234 * return second entry. 4235 */ 4236 4237 entry = &ukh->ukh_entries[1]; 4238 entry->flags = UVM_MAP_KERNEL; 4239 UVMMAP_EVCNT_INCR(ukh_alloc); 4240 return entry; 4241 } 4242 4243 /* 4244 * uvm_mapent_free: free map entry for in-kernel map 4245 */ 4246 4247 static void 4248 uvm_kmapent_free(struct vm_map_entry *entry) 4249 { 4250 struct uvm_kmapent_hdr *ukh; 4251 struct vm_page *pg; 4252 struct vm_map *map; 4253 struct pmap *pmap; 4254 vaddr_t va; 4255 paddr_t pa; 4256 struct vm_map_entry *deadentry; 4257 int s; 4258 4259 UVMMAP_EVCNT_INCR(uke_free); 4260 ukh = UVM_KHDR_FIND(entry); 4261 map = ukh->ukh_map; 4262 4263 s = splvm(); 4264 simple_lock(&uvm.kentry_lock); 4265 uvm_kmapent_put(ukh, entry); 4266 if (ukh->ukh_nused > 1) { 4267 if (ukh->ukh_nused == UVM_KMAPENT_CHUNK - 1) 4268 LIST_INSERT_HEAD( 4269 &vm_map_to_kernel(map)->vmk_kentry_free, 4270 ukh, ukh_listq); 4271 simple_unlock(&uvm.kentry_lock); 4272 splx(s); 4273 return; 4274 } 4275 4276 /* 4277 * now we can free this ukh. 4278 * 4279 * however, keep an empty ukh to avoid ping-pong. 4280 */ 4281 4282 if (LIST_FIRST(&vm_map_to_kernel(map)->vmk_kentry_free) == ukh && 4283 LIST_NEXT(ukh, ukh_listq) == NULL) { 4284 simple_unlock(&uvm.kentry_lock); 4285 splx(s); 4286 return; 4287 } 4288 LIST_REMOVE(ukh, ukh_listq); 4289 simple_unlock(&uvm.kentry_lock); 4290 splx(s); 4291 4292 KASSERT(ukh->ukh_nused == 1); 4293 4294 /* 4295 * remove map entry for ukh itsself. 4296 */ 4297 4298 va = (vaddr_t)ukh; 4299 KASSERT((va & PAGE_MASK) == 0); 4300 vm_map_lock(map); 4301 uvm_unmap_remove(map, va, va + PAGE_SIZE, &deadentry, NULL, 0); 4302 KASSERT(deadentry->flags & UVM_MAP_KERNEL); 4303 KASSERT(deadentry->flags & UVM_MAP_KMAPENT); 4304 KASSERT(deadentry->next == NULL); 4305 KASSERT(deadentry == &ukh->ukh_entries[0]); 4306 4307 /* 4308 * unmap the page from pmap and free it. 4309 */ 4310 4311 pmap = vm_map_pmap(map); 4312 KASSERT(pmap == pmap_kernel()); 4313 if (!pmap_extract(pmap, va, &pa)) 4314 panic("%s: no mapping", __func__); 4315 pmap_kremove(va, PAGE_SIZE); 4316 vm_map_unlock(map); 4317 pg = PHYS_TO_VM_PAGE(pa); 4318 uvm_pagefree(pg); 4319 UVMMAP_EVCNT_INCR(ukh_free); 4320 } 4321 4322 /* 4323 * map entry reservation 4324 */ 4325 4326 /* 4327 * uvm_mapent_reserve: reserve map entries for clipping before locking map. 4328 * 4329 * => needed when unmapping entries allocated without UVM_FLAG_QUANTUM. 4330 * => caller shouldn't hold map locked. 4331 */ 4332 int 4333 uvm_mapent_reserve(struct vm_map *map, struct uvm_mapent_reservation *umr, 4334 int nentries, int flags) 4335 { 4336 4337 umr->umr_nentries = 0; 4338 4339 if ((flags & UVM_FLAG_QUANTUM) != 0) 4340 return 0; 4341 4342 if (!VM_MAP_USE_KMAPENT(map)) 4343 return 0; 4344 4345 while (nentries--) { 4346 struct vm_map_entry *ent; 4347 ent = uvm_kmapent_alloc(map, flags); 4348 if (!ent) { 4349 uvm_mapent_unreserve(map, umr); 4350 return ENOMEM; 4351 } 4352 UMR_PUTENTRY(umr, ent); 4353 } 4354 4355 return 0; 4356 } 4357 4358 /* 4359 * uvm_mapent_unreserve: 4360 * 4361 * => caller shouldn't hold map locked. 4362 * => never fail or sleep. 4363 */ 4364 void 4365 uvm_mapent_unreserve(struct vm_map *map, struct uvm_mapent_reservation *umr) 4366 { 4367 4368 while (!UMR_EMPTY(umr)) 4369 uvm_kmapent_free(UMR_GETENTRY(umr)); 4370 } 4371 4372 /* 4373 * uvm_mapent_trymerge: try to merge an entry with its neighbors. 4374 * 4375 * => called with map locked. 4376 * => return non zero if successfully merged. 4377 */ 4378 4379 int 4380 uvm_mapent_trymerge(struct vm_map *map, struct vm_map_entry *entry, int flags) 4381 { 4382 struct uvm_object *uobj; 4383 struct vm_map_entry *next; 4384 struct vm_map_entry *prev; 4385 vsize_t size; 4386 int merged = 0; 4387 boolean_t copying; 4388 int newetype; 4389 4390 if (VM_MAP_USE_KMAPENT(map)) { 4391 return 0; 4392 } 4393 if (entry->aref.ar_amap != NULL) { 4394 return 0; 4395 } 4396 if ((entry->flags & UVM_MAP_NOMERGE) != 0) { 4397 return 0; 4398 } 4399 4400 uobj = entry->object.uvm_obj; 4401 size = entry->end - entry->start; 4402 copying = (flags & UVM_MERGE_COPYING) != 0; 4403 newetype = copying ? (entry->etype & ~UVM_ET_NEEDSCOPY) : entry->etype; 4404 4405 next = entry->next; 4406 if (next != &map->header && 4407 next->start == entry->end && 4408 ((copying && next->aref.ar_amap != NULL && 4409 amap_refs(next->aref.ar_amap) == 1) || 4410 (!copying && next->aref.ar_amap == NULL)) && 4411 UVM_ET_ISCOMPATIBLE(next, newetype, 4412 uobj, entry->flags, entry->protection, 4413 entry->max_protection, entry->inheritance, entry->advice, 4414 entry->wired_count) && 4415 (uobj == NULL || entry->offset + size == next->offset)) { 4416 int error; 4417 4418 if (copying) { 4419 error = amap_extend(next, size, 4420 AMAP_EXTEND_NOWAIT|AMAP_EXTEND_BACKWARDS); 4421 } else { 4422 error = 0; 4423 } 4424 if (error == 0) { 4425 if (uobj) { 4426 if (uobj->pgops->pgo_detach) { 4427 uobj->pgops->pgo_detach(uobj); 4428 } 4429 } 4430 4431 entry->end = next->end; 4432 uvm_map_entry_unlink(map, next); 4433 if (copying) { 4434 entry->aref = next->aref; 4435 entry->etype &= ~UVM_ET_NEEDSCOPY; 4436 } 4437 uvm_tree_sanity(map, "trymerge forwardmerge"); 4438 uvm_mapent_free_merged(map, next); 4439 merged++; 4440 } 4441 } 4442 4443 prev = entry->prev; 4444 if (prev != &map->header && 4445 prev->end == entry->start && 4446 ((copying && !merged && prev->aref.ar_amap != NULL && 4447 amap_refs(prev->aref.ar_amap) == 1) || 4448 (!copying && prev->aref.ar_amap == NULL)) && 4449 UVM_ET_ISCOMPATIBLE(prev, newetype, 4450 uobj, entry->flags, entry->protection, 4451 entry->max_protection, entry->inheritance, entry->advice, 4452 entry->wired_count) && 4453 (uobj == NULL || 4454 prev->offset + prev->end - prev->start == entry->offset)) { 4455 int error; 4456 4457 if (copying) { 4458 error = amap_extend(prev, size, 4459 AMAP_EXTEND_NOWAIT|AMAP_EXTEND_FORWARDS); 4460 } else { 4461 error = 0; 4462 } 4463 if (error == 0) { 4464 if (uobj) { 4465 if (uobj->pgops->pgo_detach) { 4466 uobj->pgops->pgo_detach(uobj); 4467 } 4468 entry->offset = prev->offset; 4469 } 4470 4471 entry->start = prev->start; 4472 uvm_map_entry_unlink(map, prev); 4473 if (copying) { 4474 entry->aref = prev->aref; 4475 entry->etype &= ~UVM_ET_NEEDSCOPY; 4476 } 4477 uvm_tree_sanity(map, "trymerge backmerge"); 4478 uvm_mapent_free_merged(map, prev); 4479 merged++; 4480 } 4481 } 4482 4483 return merged; 4484 } 4485 4486 #if defined(DDB) 4487 4488 /* 4489 * DDB hooks 4490 */ 4491 4492 /* 4493 * uvm_map_printit: actually prints the map 4494 */ 4495 4496 void 4497 uvm_map_printit(struct vm_map *map, boolean_t full, 4498 void (*pr)(const char *, ...)) 4499 { 4500 struct vm_map_entry *entry; 4501 4502 (*pr)("MAP %p: [0x%lx->0x%lx]\n", map, vm_map_min(map), 4503 vm_map_max(map)); 4504 (*pr)("\t#ent=%d, sz=%d, ref=%d, version=%d, flags=0x%x\n", 4505 map->nentries, map->size, map->ref_count, map->timestamp, 4506 map->flags); 4507 (*pr)("\tpmap=%p(resident=%ld, wired=%ld)\n", map->pmap, 4508 pmap_resident_count(map->pmap), pmap_wired_count(map->pmap)); 4509 if (!full) 4510 return; 4511 for (entry = map->header.next; entry != &map->header; 4512 entry = entry->next) { 4513 (*pr)(" - %p: 0x%lx->0x%lx: obj=%p/0x%llx, amap=%p/%d\n", 4514 entry, entry->start, entry->end, entry->object.uvm_obj, 4515 (long long)entry->offset, entry->aref.ar_amap, 4516 entry->aref.ar_pageoff); 4517 (*pr)( 4518 "\tsubmap=%c, cow=%c, nc=%c, prot(max)=%d/%d, inh=%d, " 4519 "wc=%d, adv=%d\n", 4520 (entry->etype & UVM_ET_SUBMAP) ? 'T' : 'F', 4521 (entry->etype & UVM_ET_COPYONWRITE) ? 'T' : 'F', 4522 (entry->etype & UVM_ET_NEEDSCOPY) ? 'T' : 'F', 4523 entry->protection, entry->max_protection, 4524 entry->inheritance, entry->wired_count, entry->advice); 4525 } 4526 } 4527 4528 /* 4529 * uvm_object_printit: actually prints the object 4530 */ 4531 4532 void 4533 uvm_object_printit(struct uvm_object *uobj, boolean_t full, 4534 void (*pr)(const char *, ...)) 4535 { 4536 struct vm_page *pg; 4537 int cnt = 0; 4538 4539 (*pr)("OBJECT %p: locked=%d, pgops=%p, npages=%d, ", 4540 uobj, uobj->vmobjlock.lock_data, uobj->pgops, uobj->uo_npages); 4541 if (UVM_OBJ_IS_KERN_OBJECT(uobj)) 4542 (*pr)("refs=<SYSTEM>\n"); 4543 else 4544 (*pr)("refs=%d\n", uobj->uo_refs); 4545 4546 if (!full) { 4547 return; 4548 } 4549 (*pr)(" PAGES <pg,offset>:\n "); 4550 TAILQ_FOREACH(pg, &uobj->memq, listq) { 4551 cnt++; 4552 (*pr)("<%p,0x%llx> ", pg, (long long)pg->offset); 4553 if ((cnt % 3) == 0) { 4554 (*pr)("\n "); 4555 } 4556 } 4557 if ((cnt % 3) != 0) { 4558 (*pr)("\n"); 4559 } 4560 } 4561 4562 /* 4563 * uvm_page_printit: actually print the page 4564 */ 4565 4566 static const char page_flagbits[] = 4567 "\20\1BUSY\2WANTED\3TABLED\4CLEAN\5PAGEOUT\6RELEASED\7FAKE\10RDONLY" 4568 "\11ZERO\15PAGER1"; 4569 static const char page_pqflagbits[] = 4570 "\20\1FREE\2INACTIVE\3ACTIVE\5ANON\6AOBJ"; 4571 4572 void 4573 uvm_page_printit(struct vm_page *pg, boolean_t full, 4574 void (*pr)(const char *, ...)) 4575 { 4576 struct vm_page *tpg; 4577 struct uvm_object *uobj; 4578 struct pglist *pgl; 4579 char pgbuf[128]; 4580 char pqbuf[128]; 4581 4582 (*pr)("PAGE %p:\n", pg); 4583 bitmask_snprintf(pg->flags, page_flagbits, pgbuf, sizeof(pgbuf)); 4584 bitmask_snprintf(pg->pqflags, page_pqflagbits, pqbuf, sizeof(pqbuf)); 4585 (*pr)(" flags=%s, pqflags=%s, wire_count=%d, pa=0x%lx\n", 4586 pgbuf, pqbuf, pg->wire_count, (long)VM_PAGE_TO_PHYS(pg)); 4587 (*pr)(" uobject=%p, uanon=%p, offset=0x%llx loan_count=%d\n", 4588 pg->uobject, pg->uanon, (long long)pg->offset, pg->loan_count); 4589 #if defined(UVM_PAGE_TRKOWN) 4590 if (pg->flags & PG_BUSY) 4591 (*pr)(" owning process = %d, tag=%s\n", 4592 pg->owner, pg->owner_tag); 4593 else 4594 (*pr)(" page not busy, no owner\n"); 4595 #else 4596 (*pr)(" [page ownership tracking disabled]\n"); 4597 #endif 4598 4599 if (!full) 4600 return; 4601 4602 /* cross-verify object/anon */ 4603 if ((pg->pqflags & PQ_FREE) == 0) { 4604 if (pg->pqflags & PQ_ANON) { 4605 if (pg->uanon == NULL || pg->uanon->an_page != pg) 4606 (*pr)(" >>> ANON DOES NOT POINT HERE <<< (%p)\n", 4607 (pg->uanon) ? pg->uanon->an_page : NULL); 4608 else 4609 (*pr)(" anon backpointer is OK\n"); 4610 } else { 4611 uobj = pg->uobject; 4612 if (uobj) { 4613 (*pr)(" checking object list\n"); 4614 TAILQ_FOREACH(tpg, &uobj->memq, listq) { 4615 if (tpg == pg) { 4616 break; 4617 } 4618 } 4619 if (tpg) 4620 (*pr)(" page found on object list\n"); 4621 else 4622 (*pr)(" >>> PAGE NOT FOUND ON OBJECT LIST! <<<\n"); 4623 } 4624 } 4625 } 4626 4627 /* cross-verify page queue */ 4628 if (pg->pqflags & PQ_FREE) { 4629 int fl = uvm_page_lookup_freelist(pg); 4630 int color = VM_PGCOLOR_BUCKET(pg); 4631 pgl = &uvm.page_free[fl].pgfl_buckets[color].pgfl_queues[ 4632 ((pg)->flags & PG_ZERO) ? PGFL_ZEROS : PGFL_UNKNOWN]; 4633 } else if (pg->pqflags & PQ_INACTIVE) { 4634 pgl = &uvm.page_inactive; 4635 } else if (pg->pqflags & PQ_ACTIVE) { 4636 pgl = &uvm.page_active; 4637 } else { 4638 pgl = NULL; 4639 } 4640 4641 if (pgl) { 4642 (*pr)(" checking pageq list\n"); 4643 TAILQ_FOREACH(tpg, pgl, pageq) { 4644 if (tpg == pg) { 4645 break; 4646 } 4647 } 4648 if (tpg) 4649 (*pr)(" page found on pageq list\n"); 4650 else 4651 (*pr)(" >>> PAGE NOT FOUND ON PAGEQ LIST! <<<\n"); 4652 } 4653 } 4654 4655 /* 4656 * uvm_pages_printthem - print a summary of all managed pages 4657 */ 4658 4659 void 4660 uvm_page_printall(void (*pr)(const char *, ...)) 4661 { 4662 unsigned i; 4663 struct vm_page *pg; 4664 4665 (*pr)("%18s %4s %2s %18s %18s" 4666 #ifdef UVM_PAGE_TRKOWN 4667 " OWNER" 4668 #endif 4669 "\n", "PAGE", "FLAG", "PQ", "UOBJECT", "UANON"); 4670 for (i = 0; i < vm_nphysseg; i++) { 4671 for (pg = vm_physmem[i].pgs; pg <= vm_physmem[i].lastpg; pg++) { 4672 (*pr)("%18p %04x %02x %18p %18p", 4673 pg, pg->flags, pg->pqflags, pg->uobject, 4674 pg->uanon); 4675 #ifdef UVM_PAGE_TRKOWN 4676 if (pg->flags & PG_BUSY) 4677 (*pr)(" %d [%s]", pg->owner, pg->owner_tag); 4678 #endif 4679 (*pr)("\n"); 4680 } 4681 } 4682 } 4683 4684 #endif 4685 4686 /* 4687 * uvm_map_create: create map 4688 */ 4689 4690 struct vm_map * 4691 uvm_map_create(pmap_t pmap, vaddr_t vmin, vaddr_t vmax, int flags) 4692 { 4693 struct vm_map *result; 4694 4695 MALLOC(result, struct vm_map *, sizeof(struct vm_map), 4696 M_VMMAP, M_WAITOK); 4697 uvm_map_setup(result, vmin, vmax, flags); 4698 result->pmap = pmap; 4699 return(result); 4700 } 4701 4702 /* 4703 * uvm_map_setup: init map 4704 * 4705 * => map must not be in service yet. 4706 */ 4707 4708 void 4709 uvm_map_setup(struct vm_map *map, vaddr_t vmin, vaddr_t vmax, int flags) 4710 { 4711 4712 RB_INIT(&map->rbhead); 4713 map->header.next = map->header.prev = &map->header; 4714 map->nentries = 0; 4715 map->size = 0; 4716 map->ref_count = 1; 4717 vm_map_setmin(map, vmin); 4718 vm_map_setmax(map, vmax); 4719 map->flags = flags; 4720 map->first_free = &map->header; 4721 map->hint = &map->header; 4722 map->timestamp = 0; 4723 lockinit(&map->lock, PVM, "vmmaplk", 0, 0); 4724 simple_lock_init(&map->ref_lock); 4725 simple_lock_init(&map->hint_lock); 4726 simple_lock_init(&map->flags_lock); 4727 } 4728 4729 4730 /* 4731 * U N M A P - m a i n e n t r y p o i n t 4732 */ 4733 4734 /* 4735 * uvm_unmap1: remove mappings from a vm_map (from "start" up to "stop") 4736 * 4737 * => caller must check alignment and size 4738 * => map must be unlocked (we will lock it) 4739 * => flags is UVM_FLAG_QUANTUM or 0. 4740 */ 4741 4742 void 4743 uvm_unmap1(struct vm_map *map, vaddr_t start, vaddr_t end, int flags) 4744 { 4745 struct vm_map_entry *dead_entries; 4746 struct uvm_mapent_reservation umr; 4747 UVMHIST_FUNC("uvm_unmap"); UVMHIST_CALLED(maphist); 4748 4749 UVMHIST_LOG(maphist, " (map=0x%x, start=0x%x, end=0x%x)", 4750 map, start, end, 0); 4751 /* 4752 * work now done by helper functions. wipe the pmap's and then 4753 * detach from the dead entries... 4754 */ 4755 uvm_mapent_reserve(map, &umr, 2, flags); 4756 vm_map_lock(map); 4757 uvm_unmap_remove(map, start, end, &dead_entries, &umr, flags); 4758 vm_map_unlock(map); 4759 uvm_mapent_unreserve(map, &umr); 4760 4761 if (dead_entries != NULL) 4762 uvm_unmap_detach(dead_entries, 0); 4763 4764 UVMHIST_LOG(maphist, "<- done", 0,0,0,0); 4765 } 4766 4767 4768 /* 4769 * uvm_map_reference: add reference to a map 4770 * 4771 * => map need not be locked (we use ref_lock). 4772 */ 4773 4774 void 4775 uvm_map_reference(struct vm_map *map) 4776 { 4777 simple_lock(&map->ref_lock); 4778 map->ref_count++; 4779 simple_unlock(&map->ref_lock); 4780 } 4781 4782 struct vm_map_kernel * 4783 vm_map_to_kernel(struct vm_map *map) 4784 { 4785 4786 KASSERT(VM_MAP_IS_KERNEL(map)); 4787 4788 return (struct vm_map_kernel *)map; 4789 } 4790