1 /* $OpenBSD: uvm_map.c,v 1.246 2019/06/14 05:52:43 deraadt Exp $ */ 2 /* $NetBSD: uvm_map.c,v 1.86 2000/11/27 08:40:03 chs Exp $ */ 3 4 /* 5 * Copyright (c) 2011 Ariane van der Steldt <ariane@openbsd.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 * 19 * 20 * Copyright (c) 1997 Charles D. Cranor and Washington University. 21 * Copyright (c) 1991, 1993, The Regents of the University of California. 22 * 23 * All rights reserved. 24 * 25 * This code is derived from software contributed to Berkeley by 26 * The Mach Operating System project at Carnegie-Mellon University. 27 * 28 * Redistribution and use in source and binary forms, with or without 29 * modification, are permitted provided that the following conditions 30 * are met: 31 * 1. Redistributions of source code must retain the above copyright 32 * notice, this list of conditions and the following disclaimer. 33 * 2. Redistributions in binary form must reproduce the above copyright 34 * notice, this list of conditions and the following disclaimer in the 35 * documentation and/or other materials provided with the distribution. 36 * 3. Neither the name of the University nor the names of its contributors 37 * may be used to endorse or promote products derived from this software 38 * without specific prior written permission. 39 * 40 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 43 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 50 * SUCH DAMAGE. 51 * 52 * @(#)vm_map.c 8.3 (Berkeley) 1/12/94 53 * from: Id: uvm_map.c,v 1.1.2.27 1998/02/07 01:16:54 chs Exp 54 * 55 * 56 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 57 * All rights reserved. 58 * 59 * Permission to use, copy, modify and distribute this software and 60 * its documentation is hereby granted, provided that both the copyright 61 * notice and this permission notice appear in all copies of the 62 * software, derivative works or modified versions, and any portions 63 * thereof, and that both notices appear in supporting documentation. 64 * 65 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 66 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 67 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 68 * 69 * Carnegie Mellon requests users of this software to return to 70 * 71 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 72 * School of Computer Science 73 * Carnegie Mellon University 74 * Pittsburgh PA 15213-3890 75 * 76 * any improvements or extensions that they make and grant Carnegie the 77 * rights to redistribute these changes. 78 */ 79 80 /* 81 * uvm_map.c: uvm map operations 82 */ 83 84 /* #define DEBUG */ 85 /* #define VMMAP_DEBUG */ 86 87 #include <sys/param.h> 88 #include <sys/systm.h> 89 #include <sys/mman.h> 90 #include <sys/proc.h> 91 #include <sys/malloc.h> 92 #include <sys/pool.h> 93 #include <sys/sysctl.h> 94 #include <sys/signalvar.h> 95 #include <sys/syslog.h> 96 #include <sys/user.h> 97 98 #ifdef SYSVSHM 99 #include <sys/shm.h> 100 #endif 101 102 #include <uvm/uvm.h> 103 104 #ifdef DDB 105 #include <uvm/uvm_ddb.h> 106 #endif 107 108 #include <uvm/uvm_addr.h> 109 110 111 vsize_t uvmspace_dused(struct vm_map*, vaddr_t, vaddr_t); 112 int uvm_mapent_isjoinable(struct vm_map*, 113 struct vm_map_entry*, struct vm_map_entry*); 114 struct vm_map_entry *uvm_mapent_merge(struct vm_map*, struct vm_map_entry*, 115 struct vm_map_entry*, struct uvm_map_deadq*); 116 struct vm_map_entry *uvm_mapent_tryjoin(struct vm_map*, 117 struct vm_map_entry*, struct uvm_map_deadq*); 118 struct vm_map_entry *uvm_map_mkentry(struct vm_map*, struct vm_map_entry*, 119 struct vm_map_entry*, vaddr_t, vsize_t, int, 120 struct uvm_map_deadq*, struct vm_map_entry*); 121 struct vm_map_entry *uvm_mapent_alloc(struct vm_map*, int); 122 void uvm_mapent_free(struct vm_map_entry*); 123 void uvm_unmap_kill_entry(struct vm_map*, 124 struct vm_map_entry*); 125 void uvm_unmap_detach_intrsafe(struct uvm_map_deadq *); 126 void uvm_mapent_mkfree(struct vm_map*, 127 struct vm_map_entry*, struct vm_map_entry**, 128 struct uvm_map_deadq*, boolean_t); 129 void uvm_map_pageable_pgon(struct vm_map*, 130 struct vm_map_entry*, struct vm_map_entry*, 131 vaddr_t, vaddr_t); 132 int uvm_map_pageable_wire(struct vm_map*, 133 struct vm_map_entry*, struct vm_map_entry*, 134 vaddr_t, vaddr_t, int); 135 void uvm_map_setup_entries(struct vm_map*); 136 void uvm_map_setup_md(struct vm_map*); 137 void uvm_map_teardown(struct vm_map*); 138 void uvm_map_vmspace_update(struct vm_map*, 139 struct uvm_map_deadq*, int); 140 void uvm_map_kmem_grow(struct vm_map*, 141 struct uvm_map_deadq*, vsize_t, int); 142 void uvm_map_freelist_update_clear(struct vm_map*, 143 struct uvm_map_deadq*); 144 void uvm_map_freelist_update_refill(struct vm_map *, int); 145 void uvm_map_freelist_update(struct vm_map*, 146 struct uvm_map_deadq*, vaddr_t, vaddr_t, 147 vaddr_t, vaddr_t, int); 148 struct vm_map_entry *uvm_map_fix_space(struct vm_map*, struct vm_map_entry*, 149 vaddr_t, vaddr_t, int); 150 int uvm_map_sel_limits(vaddr_t*, vaddr_t*, vsize_t, int, 151 struct vm_map_entry*, vaddr_t, vaddr_t, vaddr_t, 152 int); 153 int uvm_map_findspace(struct vm_map*, 154 struct vm_map_entry**, struct vm_map_entry**, 155 vaddr_t*, vsize_t, vaddr_t, vaddr_t, vm_prot_t, 156 vaddr_t); 157 vsize_t uvm_map_addr_augment_get(struct vm_map_entry*); 158 void uvm_map_addr_augment(struct vm_map_entry*); 159 160 /* 161 * Tree management functions. 162 */ 163 164 static __inline void uvm_mapent_copy(struct vm_map_entry*, 165 struct vm_map_entry*); 166 static inline int uvm_mapentry_addrcmp(const struct vm_map_entry*, 167 const struct vm_map_entry*); 168 void uvm_mapent_free_insert(struct vm_map*, 169 struct uvm_addr_state*, struct vm_map_entry*); 170 void uvm_mapent_free_remove(struct vm_map*, 171 struct uvm_addr_state*, struct vm_map_entry*); 172 void uvm_mapent_addr_insert(struct vm_map*, 173 struct vm_map_entry*); 174 void uvm_mapent_addr_remove(struct vm_map*, 175 struct vm_map_entry*); 176 void uvm_map_splitentry(struct vm_map*, 177 struct vm_map_entry*, struct vm_map_entry*, 178 vaddr_t); 179 vsize_t uvm_map_boundary(struct vm_map*, vaddr_t, vaddr_t); 180 int uvm_mapent_bias(struct vm_map*, struct vm_map_entry*); 181 182 /* 183 * uvm_vmspace_fork helper functions. 184 */ 185 struct vm_map_entry *uvm_mapent_clone(struct vm_map*, vaddr_t, vsize_t, 186 vsize_t, vm_prot_t, vm_prot_t, 187 struct vm_map_entry*, struct uvm_map_deadq*, int, 188 int); 189 struct vm_map_entry *uvm_mapent_share(struct vm_map*, vaddr_t, vsize_t, 190 vsize_t, vm_prot_t, vm_prot_t, struct vm_map*, 191 struct vm_map_entry*, struct uvm_map_deadq*); 192 struct vm_map_entry *uvm_mapent_forkshared(struct vmspace*, struct vm_map*, 193 struct vm_map*, struct vm_map_entry*, 194 struct uvm_map_deadq*); 195 struct vm_map_entry *uvm_mapent_forkcopy(struct vmspace*, struct vm_map*, 196 struct vm_map*, struct vm_map_entry*, 197 struct uvm_map_deadq*); 198 struct vm_map_entry *uvm_mapent_forkzero(struct vmspace*, struct vm_map*, 199 struct vm_map*, struct vm_map_entry*, 200 struct uvm_map_deadq*); 201 202 /* 203 * Tree validation. 204 */ 205 #ifdef VMMAP_DEBUG 206 void uvm_tree_assert(struct vm_map*, int, char*, 207 char*, int); 208 #define UVM_ASSERT(map, cond, file, line) \ 209 uvm_tree_assert((map), (cond), #cond, (file), (line)) 210 void uvm_tree_sanity(struct vm_map*, char*, int); 211 void uvm_tree_size_chk(struct vm_map*, char*, int); 212 void vmspace_validate(struct vm_map*); 213 #else 214 #define uvm_tree_sanity(_map, _file, _line) do {} while (0) 215 #define uvm_tree_size_chk(_map, _file, _line) do {} while (0) 216 #define vmspace_validate(_map) do {} while (0) 217 #endif 218 219 /* 220 * All architectures will have pmap_prefer. 221 */ 222 #ifndef PMAP_PREFER 223 #define PMAP_PREFER_ALIGN() (vaddr_t)PAGE_SIZE 224 #define PMAP_PREFER_OFFSET(off) 0 225 #define PMAP_PREFER(addr, off) (addr) 226 #endif 227 228 229 /* 230 * The kernel map will initially be VM_MAP_KSIZE_INIT bytes. 231 * Every time that gets cramped, we grow by at least VM_MAP_KSIZE_DELTA bytes. 232 * 233 * We attempt to grow by UVM_MAP_KSIZE_ALLOCMUL times the allocation size 234 * each time. 235 */ 236 #define VM_MAP_KSIZE_INIT (512 * (vaddr_t)PAGE_SIZE) 237 #define VM_MAP_KSIZE_DELTA (256 * (vaddr_t)PAGE_SIZE) 238 #define VM_MAP_KSIZE_ALLOCMUL 4 239 /* 240 * When selecting a random free-space block, look at most FSPACE_DELTA blocks 241 * ahead. 242 */ 243 #define FSPACE_DELTA 8 244 /* 245 * Put allocations adjecent to previous allocations when the free-space tree 246 * is larger than FSPACE_COMPACT entries. 247 * 248 * Alignment and PMAP_PREFER may still cause the entry to not be fully 249 * adjecent. Note that this strategy reduces memory fragmentation (by leaving 250 * a large space before or after the allocation). 251 */ 252 #define FSPACE_COMPACT 128 253 /* 254 * Make the address selection skip at most this many bytes from the start of 255 * the free space in which the allocation takes place. 256 * 257 * The main idea behind a randomized address space is that an attacker cannot 258 * know where to target his attack. Therefore, the location of objects must be 259 * as random as possible. However, the goal is not to create the most sparse 260 * map that is possible. 261 * FSPACE_MAXOFF pushes the considered range in bytes down to less insane 262 * sizes, thereby reducing the sparseness. The biggest randomization comes 263 * from fragmentation, i.e. FSPACE_COMPACT. 264 */ 265 #define FSPACE_MAXOFF ((vaddr_t)32 * 1024 * 1024) 266 /* 267 * Allow for small gaps in the overflow areas. 268 * Gap size is in bytes and does not have to be a multiple of page-size. 269 */ 270 #define FSPACE_BIASGAP ((vaddr_t)32 * 1024) 271 272 /* auto-allocate address lower bound */ 273 #define VMMAP_MIN_ADDR PAGE_SIZE 274 275 276 #ifdef DEADBEEF0 277 #define UVMMAP_DEADBEEF ((unsigned long)DEADBEEF0) 278 #else 279 #define UVMMAP_DEADBEEF ((unsigned long)0xdeadd0d0) 280 #endif 281 282 #ifdef DEBUG 283 int uvm_map_printlocks = 0; 284 285 #define LPRINTF(_args) \ 286 do { \ 287 if (uvm_map_printlocks) \ 288 printf _args; \ 289 } while (0) 290 #else 291 #define LPRINTF(_args) do {} while (0) 292 #endif 293 294 static struct mutex uvm_kmapent_mtx; 295 static struct timeval uvm_kmapent_last_warn_time; 296 static struct timeval uvm_kmapent_warn_rate = { 10, 0 }; 297 298 const char vmmapbsy[] = "vmmapbsy"; 299 300 /* 301 * pool for vmspace structures. 302 */ 303 struct pool uvm_vmspace_pool; 304 305 /* 306 * pool for dynamically-allocated map entries. 307 */ 308 struct pool uvm_map_entry_pool; 309 struct pool uvm_map_entry_kmem_pool; 310 311 /* 312 * This global represents the end of the kernel virtual address 313 * space. If we want to exceed this, we must grow the kernel 314 * virtual address space dynamically. 315 * 316 * Note, this variable is locked by kernel_map's lock. 317 */ 318 vaddr_t uvm_maxkaddr; 319 320 /* 321 * Locking predicate. 322 */ 323 #define UVM_MAP_REQ_WRITE(_map) \ 324 do { \ 325 if ((_map)->ref_count > 0) { \ 326 if (((_map)->flags & VM_MAP_INTRSAFE) == 0) \ 327 rw_assert_wrlock(&(_map)->lock); \ 328 else \ 329 MUTEX_ASSERT_LOCKED(&(_map)->mtx); \ 330 } \ 331 } while (0) 332 333 /* 334 * Tree describing entries by address. 335 * 336 * Addresses are unique. 337 * Entries with start == end may only exist if they are the first entry 338 * (sorted by address) within a free-memory tree. 339 */ 340 341 static inline int 342 uvm_mapentry_addrcmp(const struct vm_map_entry *e1, 343 const struct vm_map_entry *e2) 344 { 345 return e1->start < e2->start ? -1 : e1->start > e2->start; 346 } 347 348 /* 349 * Copy mapentry. 350 */ 351 static __inline void 352 uvm_mapent_copy(struct vm_map_entry *src, struct vm_map_entry *dst) 353 { 354 caddr_t csrc, cdst; 355 size_t sz; 356 357 csrc = (caddr_t)src; 358 cdst = (caddr_t)dst; 359 csrc += offsetof(struct vm_map_entry, uvm_map_entry_start_copy); 360 cdst += offsetof(struct vm_map_entry, uvm_map_entry_start_copy); 361 362 sz = offsetof(struct vm_map_entry, uvm_map_entry_stop_copy) - 363 offsetof(struct vm_map_entry, uvm_map_entry_start_copy); 364 memcpy(cdst, csrc, sz); 365 } 366 367 /* 368 * Handle free-list insertion. 369 */ 370 void 371 uvm_mapent_free_insert(struct vm_map *map, struct uvm_addr_state *uaddr, 372 struct vm_map_entry *entry) 373 { 374 const struct uvm_addr_functions *fun; 375 #ifdef VMMAP_DEBUG 376 vaddr_t min, max, bound; 377 #endif 378 379 #ifdef VMMAP_DEBUG 380 /* 381 * Boundary check. 382 * Boundaries are folded if they go on the same free list. 383 */ 384 min = VMMAP_FREE_START(entry); 385 max = VMMAP_FREE_END(entry); 386 387 while (min < max) { 388 bound = uvm_map_boundary(map, min, max); 389 KASSERT(uvm_map_uaddr(map, min) == uaddr); 390 min = bound; 391 } 392 #endif 393 KDASSERT((entry->fspace & (vaddr_t)PAGE_MASK) == 0); 394 KASSERT((entry->etype & UVM_ET_FREEMAPPED) == 0); 395 396 UVM_MAP_REQ_WRITE(map); 397 398 /* Actual insert: forward to uaddr pointer. */ 399 if (uaddr != NULL) { 400 fun = uaddr->uaddr_functions; 401 KDASSERT(fun != NULL); 402 if (fun->uaddr_free_insert != NULL) 403 (*fun->uaddr_free_insert)(map, uaddr, entry); 404 entry->etype |= UVM_ET_FREEMAPPED; 405 } 406 407 /* Update fspace augmentation. */ 408 uvm_map_addr_augment(entry); 409 } 410 411 /* 412 * Handle free-list removal. 413 */ 414 void 415 uvm_mapent_free_remove(struct vm_map *map, struct uvm_addr_state *uaddr, 416 struct vm_map_entry *entry) 417 { 418 const struct uvm_addr_functions *fun; 419 420 KASSERT((entry->etype & UVM_ET_FREEMAPPED) != 0 || uaddr == NULL); 421 KASSERT(uvm_map_uaddr_e(map, entry) == uaddr); 422 UVM_MAP_REQ_WRITE(map); 423 424 if (uaddr != NULL) { 425 fun = uaddr->uaddr_functions; 426 if (fun->uaddr_free_remove != NULL) 427 (*fun->uaddr_free_remove)(map, uaddr, entry); 428 entry->etype &= ~UVM_ET_FREEMAPPED; 429 } 430 } 431 432 /* 433 * Handle address tree insertion. 434 */ 435 void 436 uvm_mapent_addr_insert(struct vm_map *map, struct vm_map_entry *entry) 437 { 438 struct vm_map_entry *res; 439 440 if (!RBT_CHECK(uvm_map_addr, entry, UVMMAP_DEADBEEF)) 441 panic("uvm_mapent_addr_insert: entry still in addr list"); 442 KDASSERT(entry->start <= entry->end); 443 KDASSERT((entry->start & (vaddr_t)PAGE_MASK) == 0 && 444 (entry->end & (vaddr_t)PAGE_MASK) == 0); 445 446 UVM_MAP_REQ_WRITE(map); 447 res = RBT_INSERT(uvm_map_addr, &map->addr, entry); 448 if (res != NULL) { 449 panic("uvm_mapent_addr_insert: map %p entry %p " 450 "(0x%lx-0x%lx G=0x%lx F=0x%lx) insert collision " 451 "with entry %p (0x%lx-0x%lx G=0x%lx F=0x%lx)", 452 map, entry, 453 entry->start, entry->end, entry->guard, entry->fspace, 454 res, res->start, res->end, res->guard, res->fspace); 455 } 456 } 457 458 /* 459 * Handle address tree removal. 460 */ 461 void 462 uvm_mapent_addr_remove(struct vm_map *map, struct vm_map_entry *entry) 463 { 464 struct vm_map_entry *res; 465 466 UVM_MAP_REQ_WRITE(map); 467 res = RBT_REMOVE(uvm_map_addr, &map->addr, entry); 468 if (res != entry) 469 panic("uvm_mapent_addr_remove"); 470 RBT_POISON(uvm_map_addr, entry, UVMMAP_DEADBEEF); 471 } 472 473 /* 474 * uvm_map_reference: add reference to a map 475 * 476 * XXX check map reference counter lock 477 */ 478 #define uvm_map_reference(_map) \ 479 do { \ 480 map->ref_count++; \ 481 } while (0) 482 483 /* 484 * Calculate the dused delta. 485 */ 486 vsize_t 487 uvmspace_dused(struct vm_map *map, vaddr_t min, vaddr_t max) 488 { 489 struct vmspace *vm; 490 vsize_t sz; 491 vaddr_t lmax; 492 vaddr_t stack_begin, stack_end; /* Position of stack. */ 493 494 KASSERT(map->flags & VM_MAP_ISVMSPACE); 495 vm = (struct vmspace *)map; 496 stack_begin = MIN((vaddr_t)vm->vm_maxsaddr, (vaddr_t)vm->vm_minsaddr); 497 stack_end = MAX((vaddr_t)vm->vm_maxsaddr, (vaddr_t)vm->vm_minsaddr); 498 499 sz = 0; 500 while (min != max) { 501 lmax = max; 502 if (min < stack_begin && lmax > stack_begin) 503 lmax = stack_begin; 504 else if (min < stack_end && lmax > stack_end) 505 lmax = stack_end; 506 507 if (min >= stack_begin && min < stack_end) { 508 /* nothing */ 509 } else 510 sz += lmax - min; 511 min = lmax; 512 } 513 514 return sz >> PAGE_SHIFT; 515 } 516 517 /* 518 * Find the entry describing the given address. 519 */ 520 struct vm_map_entry* 521 uvm_map_entrybyaddr(struct uvm_map_addr *atree, vaddr_t addr) 522 { 523 struct vm_map_entry *iter; 524 525 iter = RBT_ROOT(uvm_map_addr, atree); 526 while (iter != NULL) { 527 if (iter->start > addr) 528 iter = RBT_LEFT(uvm_map_addr, iter); 529 else if (VMMAP_FREE_END(iter) <= addr) 530 iter = RBT_RIGHT(uvm_map_addr, iter); 531 else 532 return iter; 533 } 534 return NULL; 535 } 536 537 /* 538 * DEAD_ENTRY_PUSH(struct vm_map_deadq *deadq, struct vm_map_entry *entry) 539 * 540 * Push dead entries into a linked list. 541 * Since the linked list abuses the address tree for storage, the entry 542 * may not be linked in a map. 543 * 544 * *head must be initialized to NULL before the first call to this macro. 545 * uvm_unmap_detach(*head, 0) will remove dead entries. 546 */ 547 static __inline void 548 dead_entry_push(struct uvm_map_deadq *deadq, struct vm_map_entry *entry) 549 { 550 TAILQ_INSERT_TAIL(deadq, entry, dfree.deadq); 551 } 552 #define DEAD_ENTRY_PUSH(_headptr, _entry) \ 553 dead_entry_push((_headptr), (_entry)) 554 555 /* 556 * Helper function for uvm_map_findspace_tree. 557 * 558 * Given allocation constraints and pmap constraints, finds the 559 * lowest and highest address in a range that can be used for the 560 * allocation. 561 * 562 * pmap_align and pmap_off are ignored on non-PMAP_PREFER archs. 563 * 564 * 565 * Big chunk of math with a seasoning of dragons. 566 */ 567 int 568 uvm_map_sel_limits(vaddr_t *min, vaddr_t *max, vsize_t sz, int guardpg, 569 struct vm_map_entry *sel, vaddr_t align, 570 vaddr_t pmap_align, vaddr_t pmap_off, int bias) 571 { 572 vaddr_t sel_min, sel_max; 573 #ifdef PMAP_PREFER 574 vaddr_t pmap_min, pmap_max; 575 #endif /* PMAP_PREFER */ 576 #ifdef DIAGNOSTIC 577 int bad; 578 #endif /* DIAGNOSTIC */ 579 580 sel_min = VMMAP_FREE_START(sel); 581 sel_max = VMMAP_FREE_END(sel) - sz - (guardpg ? PAGE_SIZE : 0); 582 583 #ifdef PMAP_PREFER 584 585 /* 586 * There are two special cases, in which we can satisfy the align 587 * requirement and the pmap_prefer requirement. 588 * - when pmap_off == 0, we always select the largest of the two 589 * - when pmap_off % align == 0 and pmap_align > align, we simply 590 * satisfy the pmap_align requirement and automatically 591 * satisfy the align requirement. 592 */ 593 if (align > PAGE_SIZE && 594 !(pmap_align > align && (pmap_off & (align - 1)) == 0)) { 595 /* 596 * Simple case: only use align. 597 */ 598 sel_min = roundup(sel_min, align); 599 sel_max &= ~(align - 1); 600 601 if (sel_min > sel_max) 602 return ENOMEM; 603 604 /* Correct for bias. */ 605 if (sel_max - sel_min > FSPACE_BIASGAP) { 606 if (bias > 0) { 607 sel_min = sel_max - FSPACE_BIASGAP; 608 sel_min = roundup(sel_min, align); 609 } else if (bias < 0) { 610 sel_max = sel_min + FSPACE_BIASGAP; 611 sel_max &= ~(align - 1); 612 } 613 } 614 } else if (pmap_align != 0) { 615 /* 616 * Special case: satisfy both pmap_prefer and 617 * align argument. 618 */ 619 pmap_max = sel_max & ~(pmap_align - 1); 620 pmap_min = sel_min; 621 if (pmap_max < sel_min) 622 return ENOMEM; 623 624 /* Adjust pmap_min for BIASGAP for top-addr bias. */ 625 if (bias > 0 && pmap_max - pmap_min > FSPACE_BIASGAP) 626 pmap_min = pmap_max - FSPACE_BIASGAP; 627 /* Align pmap_min. */ 628 pmap_min &= ~(pmap_align - 1); 629 if (pmap_min < sel_min) 630 pmap_min += pmap_align; 631 if (pmap_min > pmap_max) 632 return ENOMEM; 633 634 /* Adjust pmap_max for BIASGAP for bottom-addr bias. */ 635 if (bias < 0 && pmap_max - pmap_min > FSPACE_BIASGAP) { 636 pmap_max = (pmap_min + FSPACE_BIASGAP) & 637 ~(pmap_align - 1); 638 } 639 if (pmap_min > pmap_max) 640 return ENOMEM; 641 642 /* Apply pmap prefer offset. */ 643 pmap_max |= pmap_off; 644 if (pmap_max > sel_max) 645 pmap_max -= pmap_align; 646 pmap_min |= pmap_off; 647 if (pmap_min < sel_min) 648 pmap_min += pmap_align; 649 650 /* 651 * Fixup: it's possible that pmap_min and pmap_max 652 * cross eachother. In this case, try to find one 653 * address that is allowed. 654 * (This usually happens in biased case.) 655 */ 656 if (pmap_min > pmap_max) { 657 if (pmap_min < sel_max) 658 pmap_max = pmap_min; 659 else if (pmap_max > sel_min) 660 pmap_min = pmap_max; 661 else 662 return ENOMEM; 663 } 664 665 /* Internal validation. */ 666 KDASSERT(pmap_min <= pmap_max); 667 668 sel_min = pmap_min; 669 sel_max = pmap_max; 670 } else if (bias > 0 && sel_max - sel_min > FSPACE_BIASGAP) 671 sel_min = sel_max - FSPACE_BIASGAP; 672 else if (bias < 0 && sel_max - sel_min > FSPACE_BIASGAP) 673 sel_max = sel_min + FSPACE_BIASGAP; 674 675 #else 676 677 if (align > PAGE_SIZE) { 678 sel_min = roundup(sel_min, align); 679 sel_max &= ~(align - 1); 680 if (sel_min > sel_max) 681 return ENOMEM; 682 683 if (bias != 0 && sel_max - sel_min > FSPACE_BIASGAP) { 684 if (bias > 0) { 685 sel_min = roundup(sel_max - FSPACE_BIASGAP, 686 align); 687 } else { 688 sel_max = (sel_min + FSPACE_BIASGAP) & 689 ~(align - 1); 690 } 691 } 692 } else if (bias > 0 && sel_max - sel_min > FSPACE_BIASGAP) 693 sel_min = sel_max - FSPACE_BIASGAP; 694 else if (bias < 0 && sel_max - sel_min > FSPACE_BIASGAP) 695 sel_max = sel_min + FSPACE_BIASGAP; 696 697 #endif 698 699 if (sel_min > sel_max) 700 return ENOMEM; 701 702 #ifdef DIAGNOSTIC 703 bad = 0; 704 /* Lower boundary check. */ 705 if (sel_min < VMMAP_FREE_START(sel)) { 706 printf("sel_min: 0x%lx, but should be at least 0x%lx\n", 707 sel_min, VMMAP_FREE_START(sel)); 708 bad++; 709 } 710 /* Upper boundary check. */ 711 if (sel_max > VMMAP_FREE_END(sel) - sz - (guardpg ? PAGE_SIZE : 0)) { 712 printf("sel_max: 0x%lx, but should be at most 0x%lx\n", 713 sel_max, 714 VMMAP_FREE_END(sel) - sz - (guardpg ? PAGE_SIZE : 0)); 715 bad++; 716 } 717 /* Lower boundary alignment. */ 718 if (align != 0 && (sel_min & (align - 1)) != 0) { 719 printf("sel_min: 0x%lx, not aligned to 0x%lx\n", 720 sel_min, align); 721 bad++; 722 } 723 /* Upper boundary alignment. */ 724 if (align != 0 && (sel_max & (align - 1)) != 0) { 725 printf("sel_max: 0x%lx, not aligned to 0x%lx\n", 726 sel_max, align); 727 bad++; 728 } 729 /* Lower boundary PMAP_PREFER check. */ 730 if (pmap_align != 0 && align == 0 && 731 (sel_min & (pmap_align - 1)) != pmap_off) { 732 printf("sel_min: 0x%lx, aligned to 0x%lx, expected 0x%lx\n", 733 sel_min, sel_min & (pmap_align - 1), pmap_off); 734 bad++; 735 } 736 /* Upper boundary PMAP_PREFER check. */ 737 if (pmap_align != 0 && align == 0 && 738 (sel_max & (pmap_align - 1)) != pmap_off) { 739 printf("sel_max: 0x%lx, aligned to 0x%lx, expected 0x%lx\n", 740 sel_max, sel_max & (pmap_align - 1), pmap_off); 741 bad++; 742 } 743 744 if (bad) { 745 panic("uvm_map_sel_limits(sz = %lu, guardpg = %c, " 746 "align = 0x%lx, pmap_align = 0x%lx, pmap_off = 0x%lx, " 747 "bias = %d, " 748 "FREE_START(sel) = 0x%lx, FREE_END(sel) = 0x%lx)", 749 sz, (guardpg ? 'T' : 'F'), align, pmap_align, pmap_off, 750 bias, VMMAP_FREE_START(sel), VMMAP_FREE_END(sel)); 751 } 752 #endif /* DIAGNOSTIC */ 753 754 *min = sel_min; 755 *max = sel_max; 756 return 0; 757 } 758 759 /* 760 * Test if memory starting at addr with sz bytes is free. 761 * 762 * Fills in *start_ptr and *end_ptr to be the first and last entry describing 763 * the space. 764 * If called with prefilled *start_ptr and *end_ptr, they are to be correct. 765 */ 766 int 767 uvm_map_isavail(struct vm_map *map, struct uvm_addr_state *uaddr, 768 struct vm_map_entry **start_ptr, struct vm_map_entry **end_ptr, 769 vaddr_t addr, vsize_t sz) 770 { 771 struct uvm_addr_state *free; 772 struct uvm_map_addr *atree; 773 struct vm_map_entry *i, *i_end; 774 775 if (addr + sz < addr) 776 return 0; 777 778 /* 779 * Kernel memory above uvm_maxkaddr is considered unavailable. 780 */ 781 if ((map->flags & VM_MAP_ISVMSPACE) == 0) { 782 if (addr + sz > uvm_maxkaddr) 783 return 0; 784 } 785 786 atree = &map->addr; 787 788 /* 789 * Fill in first, last, so they point at the entries containing the 790 * first and last address of the range. 791 * Note that if they are not NULL, we don't perform the lookup. 792 */ 793 KDASSERT(atree != NULL && start_ptr != NULL && end_ptr != NULL); 794 if (*start_ptr == NULL) { 795 *start_ptr = uvm_map_entrybyaddr(atree, addr); 796 if (*start_ptr == NULL) 797 return 0; 798 } else 799 KASSERT(*start_ptr == uvm_map_entrybyaddr(atree, addr)); 800 if (*end_ptr == NULL) { 801 if (VMMAP_FREE_END(*start_ptr) >= addr + sz) 802 *end_ptr = *start_ptr; 803 else { 804 *end_ptr = uvm_map_entrybyaddr(atree, addr + sz - 1); 805 if (*end_ptr == NULL) 806 return 0; 807 } 808 } else 809 KASSERT(*end_ptr == uvm_map_entrybyaddr(atree, addr + sz - 1)); 810 811 /* Validation. */ 812 KDASSERT(*start_ptr != NULL && *end_ptr != NULL); 813 KDASSERT((*start_ptr)->start <= addr && 814 VMMAP_FREE_END(*start_ptr) > addr && 815 (*end_ptr)->start < addr + sz && 816 VMMAP_FREE_END(*end_ptr) >= addr + sz); 817 818 /* 819 * Check the none of the entries intersects with <addr, addr+sz>. 820 * Also, if the entry belong to uaddr_exe or uaddr_brk_stack, it is 821 * considered unavailable unless called by those allocators. 822 */ 823 i = *start_ptr; 824 i_end = RBT_NEXT(uvm_map_addr, *end_ptr); 825 for (; i != i_end; 826 i = RBT_NEXT(uvm_map_addr, i)) { 827 if (i->start != i->end && i->end > addr) 828 return 0; 829 830 /* 831 * uaddr_exe and uaddr_brk_stack may only be used 832 * by these allocators and the NULL uaddr (i.e. no 833 * uaddr). 834 * Reject if this requirement is not met. 835 */ 836 if (uaddr != NULL) { 837 free = uvm_map_uaddr_e(map, i); 838 839 if (uaddr != free && free != NULL && 840 (free == map->uaddr_exe || 841 free == map->uaddr_brk_stack)) 842 return 0; 843 } 844 } 845 846 return -1; 847 } 848 849 /* 850 * Invoke each address selector until an address is found. 851 * Will not invoke uaddr_exe. 852 */ 853 int 854 uvm_map_findspace(struct vm_map *map, struct vm_map_entry**first, 855 struct vm_map_entry**last, vaddr_t *addr, vsize_t sz, 856 vaddr_t pmap_align, vaddr_t pmap_offset, vm_prot_t prot, vaddr_t hint) 857 { 858 struct uvm_addr_state *uaddr; 859 int i; 860 861 /* 862 * Allocation for sz bytes at any address, 863 * using the addr selectors in order. 864 */ 865 for (i = 0; i < nitems(map->uaddr_any); i++) { 866 uaddr = map->uaddr_any[i]; 867 868 if (uvm_addr_invoke(map, uaddr, first, last, 869 addr, sz, pmap_align, pmap_offset, prot, hint) == 0) 870 return 0; 871 } 872 873 /* Fall back to brk() and stack() address selectors. */ 874 uaddr = map->uaddr_brk_stack; 875 if (uvm_addr_invoke(map, uaddr, first, last, 876 addr, sz, pmap_align, pmap_offset, prot, hint) == 0) 877 return 0; 878 879 return ENOMEM; 880 } 881 882 /* Calculate entry augmentation value. */ 883 vsize_t 884 uvm_map_addr_augment_get(struct vm_map_entry *entry) 885 { 886 vsize_t augment; 887 struct vm_map_entry *left, *right; 888 889 augment = entry->fspace; 890 if ((left = RBT_LEFT(uvm_map_addr, entry)) != NULL) 891 augment = MAX(augment, left->fspace_augment); 892 if ((right = RBT_RIGHT(uvm_map_addr, entry)) != NULL) 893 augment = MAX(augment, right->fspace_augment); 894 return augment; 895 } 896 897 /* 898 * Update augmentation data in entry. 899 */ 900 void 901 uvm_map_addr_augment(struct vm_map_entry *entry) 902 { 903 vsize_t augment; 904 905 while (entry != NULL) { 906 /* Calculate value for augmentation. */ 907 augment = uvm_map_addr_augment_get(entry); 908 909 /* 910 * Descend update. 911 * Once we find an entry that already has the correct value, 912 * stop, since it means all its parents will use the correct 913 * value too. 914 */ 915 if (entry->fspace_augment == augment) 916 return; 917 entry->fspace_augment = augment; 918 entry = RBT_PARENT(uvm_map_addr, entry); 919 } 920 } 921 922 /* 923 * uvm_mapanon: establish a valid mapping in map for an anon 924 * 925 * => *addr and sz must be a multiple of PAGE_SIZE. 926 * => *addr is ignored, except if flags contains UVM_FLAG_FIXED. 927 * => map must be unlocked. 928 * 929 * => align: align vaddr, must be a power-of-2. 930 * Align is only a hint and will be ignored if the alignment fails. 931 */ 932 int 933 uvm_mapanon(struct vm_map *map, vaddr_t *addr, vsize_t sz, 934 vsize_t align, unsigned int flags) 935 { 936 struct vm_map_entry *first, *last, *entry, *new; 937 struct uvm_map_deadq dead; 938 vm_prot_t prot; 939 vm_prot_t maxprot; 940 vm_inherit_t inherit; 941 int advice; 942 int error; 943 vaddr_t pmap_align, pmap_offset; 944 vaddr_t hint; 945 946 KASSERT((map->flags & VM_MAP_ISVMSPACE) == VM_MAP_ISVMSPACE); 947 KASSERT(map != kernel_map); 948 KASSERT((map->flags & UVM_FLAG_HOLE) == 0); 949 950 KASSERT((map->flags & VM_MAP_INTRSAFE) == 0); 951 splassert(IPL_NONE); 952 953 /* 954 * We use pmap_align and pmap_offset as alignment and offset variables. 955 * 956 * Because the align parameter takes precedence over pmap prefer, 957 * the pmap_align will need to be set to align, with pmap_offset = 0, 958 * if pmap_prefer will not align. 959 */ 960 pmap_align = MAX(align, PAGE_SIZE); 961 pmap_offset = 0; 962 963 /* Decode parameters. */ 964 prot = UVM_PROTECTION(flags); 965 maxprot = UVM_MAXPROTECTION(flags); 966 advice = UVM_ADVICE(flags); 967 inherit = UVM_INHERIT(flags); 968 error = 0; 969 hint = trunc_page(*addr); 970 TAILQ_INIT(&dead); 971 KASSERT((sz & (vaddr_t)PAGE_MASK) == 0); 972 KASSERT((align & (align - 1)) == 0); 973 974 /* Check protection. */ 975 if ((prot & maxprot) != prot) 976 return EACCES; 977 978 /* 979 * Before grabbing the lock, allocate a map entry for later 980 * use to ensure we don't wait for memory while holding the 981 * vm_map_lock. 982 */ 983 new = uvm_mapent_alloc(map, flags); 984 if (new == NULL) 985 return(ENOMEM); 986 987 if (flags & UVM_FLAG_TRYLOCK) { 988 if (vm_map_lock_try(map) == FALSE) { 989 error = EFAULT; 990 goto out; 991 } 992 } else 993 vm_map_lock(map); 994 995 first = last = NULL; 996 if (flags & UVM_FLAG_FIXED) { 997 /* 998 * Fixed location. 999 * 1000 * Note: we ignore align, pmap_prefer. 1001 * Fill in first, last and *addr. 1002 */ 1003 KASSERT((*addr & PAGE_MASK) == 0); 1004 1005 /* Check that the space is available. */ 1006 if (flags & UVM_FLAG_UNMAP) { 1007 if ((flags & UVM_FLAG_STACK) && 1008 !uvm_map_is_stack_remappable(map, *addr, sz)) { 1009 error = EINVAL; 1010 goto unlock; 1011 } 1012 uvm_unmap_remove(map, *addr, *addr + sz, &dead, FALSE, TRUE); 1013 } 1014 if (!uvm_map_isavail(map, NULL, &first, &last, *addr, sz)) { 1015 error = ENOMEM; 1016 goto unlock; 1017 } 1018 } else if (*addr != 0 && (*addr & PAGE_MASK) == 0 && 1019 (align == 0 || (*addr & (align - 1)) == 0) && 1020 uvm_map_isavail(map, NULL, &first, &last, *addr, sz)) { 1021 /* 1022 * Address used as hint. 1023 * 1024 * Note: we enforce the alignment restriction, 1025 * but ignore pmap_prefer. 1026 */ 1027 } else if ((prot & PROT_EXEC) != 0 && map->uaddr_exe != NULL) { 1028 /* Run selection algorithm for executables. */ 1029 error = uvm_addr_invoke(map, map->uaddr_exe, &first, &last, 1030 addr, sz, pmap_align, pmap_offset, prot, hint); 1031 1032 if (error != 0) 1033 goto unlock; 1034 } else { 1035 /* Update freelists from vmspace. */ 1036 uvm_map_vmspace_update(map, &dead, flags); 1037 1038 error = uvm_map_findspace(map, &first, &last, addr, sz, 1039 pmap_align, pmap_offset, prot, hint); 1040 1041 if (error != 0) 1042 goto unlock; 1043 } 1044 1045 /* Double-check if selected address doesn't cause overflow. */ 1046 if (*addr + sz < *addr) { 1047 error = ENOMEM; 1048 goto unlock; 1049 } 1050 1051 /* If we only want a query, return now. */ 1052 if (flags & UVM_FLAG_QUERY) { 1053 error = 0; 1054 goto unlock; 1055 } 1056 1057 /* 1058 * Create new entry. 1059 * first and last may be invalidated after this call. 1060 */ 1061 entry = uvm_map_mkentry(map, first, last, *addr, sz, flags, &dead, 1062 new); 1063 if (entry == NULL) { 1064 error = ENOMEM; 1065 goto unlock; 1066 } 1067 new = NULL; 1068 KDASSERT(entry->start == *addr && entry->end == *addr + sz); 1069 entry->object.uvm_obj = NULL; 1070 entry->offset = 0; 1071 entry->protection = prot; 1072 entry->max_protection = maxprot; 1073 entry->inheritance = inherit; 1074 entry->wired_count = 0; 1075 entry->advice = advice; 1076 if (prot & PROT_WRITE) 1077 map->wserial++; 1078 if (flags & UVM_FLAG_STACK) { 1079 entry->etype |= UVM_ET_STACK; 1080 if (flags & (UVM_FLAG_FIXED | UVM_FLAG_UNMAP)) 1081 map->sserial++; 1082 } 1083 if (flags & UVM_FLAG_COPYONW) { 1084 entry->etype |= UVM_ET_COPYONWRITE; 1085 if ((flags & UVM_FLAG_OVERLAY) == 0) 1086 entry->etype |= UVM_ET_NEEDSCOPY; 1087 } 1088 if (flags & UVM_FLAG_CONCEAL) 1089 entry->etype |= UVM_ET_CONCEAL; 1090 if (flags & UVM_FLAG_OVERLAY) { 1091 KERNEL_LOCK(); 1092 entry->aref.ar_pageoff = 0; 1093 entry->aref.ar_amap = amap_alloc(sz, M_WAITOK, 0); 1094 KERNEL_UNLOCK(); 1095 } 1096 1097 /* Update map and process statistics. */ 1098 map->size += sz; 1099 ((struct vmspace *)map)->vm_dused += uvmspace_dused(map, *addr, *addr + sz); 1100 1101 unlock: 1102 vm_map_unlock(map); 1103 1104 /* 1105 * Remove dead entries. 1106 * 1107 * Dead entries may be the result of merging. 1108 * uvm_map_mkentry may also create dead entries, when it attempts to 1109 * destroy free-space entries. 1110 */ 1111 uvm_unmap_detach(&dead, 0); 1112 out: 1113 if (new) 1114 uvm_mapent_free(new); 1115 return error; 1116 } 1117 1118 /* 1119 * uvm_map: establish a valid mapping in map 1120 * 1121 * => *addr and sz must be a multiple of PAGE_SIZE. 1122 * => map must be unlocked. 1123 * => <uobj,uoffset> value meanings (4 cases): 1124 * [1] <NULL,uoffset> == uoffset is a hint for PMAP_PREFER 1125 * [2] <NULL,UVM_UNKNOWN_OFFSET> == don't PMAP_PREFER 1126 * [3] <uobj,uoffset> == normal mapping 1127 * [4] <uobj,UVM_UNKNOWN_OFFSET> == uvm_map finds offset based on VA 1128 * 1129 * case [4] is for kernel mappings where we don't know the offset until 1130 * we've found a virtual address. note that kernel object offsets are 1131 * always relative to vm_map_min(kernel_map). 1132 * 1133 * => align: align vaddr, must be a power-of-2. 1134 * Align is only a hint and will be ignored if the alignment fails. 1135 */ 1136 int 1137 uvm_map(struct vm_map *map, vaddr_t *addr, vsize_t sz, 1138 struct uvm_object *uobj, voff_t uoffset, 1139 vsize_t align, unsigned int flags) 1140 { 1141 struct vm_map_entry *first, *last, *entry, *new; 1142 struct uvm_map_deadq dead; 1143 vm_prot_t prot; 1144 vm_prot_t maxprot; 1145 vm_inherit_t inherit; 1146 int advice; 1147 int error; 1148 vaddr_t pmap_align, pmap_offset; 1149 vaddr_t hint; 1150 1151 if ((map->flags & VM_MAP_INTRSAFE) == 0) 1152 splassert(IPL_NONE); 1153 else 1154 splassert(IPL_VM); 1155 1156 /* 1157 * We use pmap_align and pmap_offset as alignment and offset variables. 1158 * 1159 * Because the align parameter takes precedence over pmap prefer, 1160 * the pmap_align will need to be set to align, with pmap_offset = 0, 1161 * if pmap_prefer will not align. 1162 */ 1163 if (uoffset == UVM_UNKNOWN_OFFSET) { 1164 pmap_align = MAX(align, PAGE_SIZE); 1165 pmap_offset = 0; 1166 } else { 1167 pmap_align = MAX(PMAP_PREFER_ALIGN(), PAGE_SIZE); 1168 pmap_offset = PMAP_PREFER_OFFSET(uoffset); 1169 1170 if (align == 0 || 1171 (align <= pmap_align && (pmap_offset & (align - 1)) == 0)) { 1172 /* pmap_offset satisfies align, no change. */ 1173 } else { 1174 /* Align takes precedence over pmap prefer. */ 1175 pmap_align = align; 1176 pmap_offset = 0; 1177 } 1178 } 1179 1180 /* Decode parameters. */ 1181 prot = UVM_PROTECTION(flags); 1182 maxprot = UVM_MAXPROTECTION(flags); 1183 advice = UVM_ADVICE(flags); 1184 inherit = UVM_INHERIT(flags); 1185 error = 0; 1186 hint = trunc_page(*addr); 1187 TAILQ_INIT(&dead); 1188 KASSERT((sz & (vaddr_t)PAGE_MASK) == 0); 1189 KASSERT((align & (align - 1)) == 0); 1190 1191 /* Holes are incompatible with other types of mappings. */ 1192 if (flags & UVM_FLAG_HOLE) { 1193 KASSERT(uobj == NULL && (flags & UVM_FLAG_FIXED) && 1194 (flags & (UVM_FLAG_OVERLAY | UVM_FLAG_COPYONW)) == 0); 1195 } 1196 1197 /* Unset hint for kernel_map non-fixed allocations. */ 1198 if (!(map->flags & VM_MAP_ISVMSPACE) && !(flags & UVM_FLAG_FIXED)) 1199 hint = 0; 1200 1201 /* Check protection. */ 1202 if ((prot & maxprot) != prot) 1203 return EACCES; 1204 1205 if (map == kernel_map && 1206 (prot & (PROT_WRITE | PROT_EXEC)) == (PROT_WRITE | PROT_EXEC)) 1207 panic("uvm_map: kernel map W^X violation requested"); 1208 1209 /* 1210 * Before grabbing the lock, allocate a map entry for later 1211 * use to ensure we don't wait for memory while holding the 1212 * vm_map_lock. 1213 */ 1214 new = uvm_mapent_alloc(map, flags); 1215 if (new == NULL) 1216 return(ENOMEM); 1217 1218 if (flags & UVM_FLAG_TRYLOCK) { 1219 if (vm_map_lock_try(map) == FALSE) { 1220 error = EFAULT; 1221 goto out; 1222 } 1223 } else { 1224 vm_map_lock(map); 1225 } 1226 1227 first = last = NULL; 1228 if (flags & UVM_FLAG_FIXED) { 1229 /* 1230 * Fixed location. 1231 * 1232 * Note: we ignore align, pmap_prefer. 1233 * Fill in first, last and *addr. 1234 */ 1235 KASSERT((*addr & PAGE_MASK) == 0); 1236 1237 /* 1238 * Grow pmap to include allocated address. 1239 * If the growth fails, the allocation will fail too. 1240 */ 1241 if ((map->flags & VM_MAP_ISVMSPACE) == 0 && 1242 uvm_maxkaddr < (*addr + sz)) { 1243 uvm_map_kmem_grow(map, &dead, 1244 *addr + sz - uvm_maxkaddr, flags); 1245 } 1246 1247 /* Check that the space is available. */ 1248 if (flags & UVM_FLAG_UNMAP) 1249 uvm_unmap_remove(map, *addr, *addr + sz, &dead, FALSE, TRUE); 1250 if (!uvm_map_isavail(map, NULL, &first, &last, *addr, sz)) { 1251 error = ENOMEM; 1252 goto unlock; 1253 } 1254 } else if (*addr != 0 && (*addr & PAGE_MASK) == 0 && 1255 (map->flags & VM_MAP_ISVMSPACE) == VM_MAP_ISVMSPACE && 1256 (align == 0 || (*addr & (align - 1)) == 0) && 1257 uvm_map_isavail(map, NULL, &first, &last, *addr, sz)) { 1258 /* 1259 * Address used as hint. 1260 * 1261 * Note: we enforce the alignment restriction, 1262 * but ignore pmap_prefer. 1263 */ 1264 } else if ((prot & PROT_EXEC) != 0 && map->uaddr_exe != NULL) { 1265 /* Run selection algorithm for executables. */ 1266 error = uvm_addr_invoke(map, map->uaddr_exe, &first, &last, 1267 addr, sz, pmap_align, pmap_offset, prot, hint); 1268 1269 /* Grow kernel memory and try again. */ 1270 if (error != 0 && (map->flags & VM_MAP_ISVMSPACE) == 0) { 1271 uvm_map_kmem_grow(map, &dead, sz, flags); 1272 1273 error = uvm_addr_invoke(map, map->uaddr_exe, 1274 &first, &last, addr, sz, 1275 pmap_align, pmap_offset, prot, hint); 1276 } 1277 1278 if (error != 0) 1279 goto unlock; 1280 } else { 1281 /* Update freelists from vmspace. */ 1282 if (map->flags & VM_MAP_ISVMSPACE) 1283 uvm_map_vmspace_update(map, &dead, flags); 1284 1285 error = uvm_map_findspace(map, &first, &last, addr, sz, 1286 pmap_align, pmap_offset, prot, hint); 1287 1288 /* Grow kernel memory and try again. */ 1289 if (error != 0 && (map->flags & VM_MAP_ISVMSPACE) == 0) { 1290 uvm_map_kmem_grow(map, &dead, sz, flags); 1291 1292 error = uvm_map_findspace(map, &first, &last, addr, sz, 1293 pmap_align, pmap_offset, prot, hint); 1294 } 1295 1296 if (error != 0) 1297 goto unlock; 1298 } 1299 1300 /* Double-check if selected address doesn't cause overflow. */ 1301 if (*addr + sz < *addr) { 1302 error = ENOMEM; 1303 goto unlock; 1304 } 1305 1306 KASSERT((map->flags & VM_MAP_ISVMSPACE) == VM_MAP_ISVMSPACE || 1307 uvm_maxkaddr >= *addr + sz); 1308 1309 /* If we only want a query, return now. */ 1310 if (flags & UVM_FLAG_QUERY) { 1311 error = 0; 1312 goto unlock; 1313 } 1314 1315 if (uobj == NULL) 1316 uoffset = 0; 1317 else if (uoffset == UVM_UNKNOWN_OFFSET) { 1318 KASSERT(UVM_OBJ_IS_KERN_OBJECT(uobj)); 1319 uoffset = *addr - vm_map_min(kernel_map); 1320 } 1321 1322 /* 1323 * Create new entry. 1324 * first and last may be invalidated after this call. 1325 */ 1326 entry = uvm_map_mkentry(map, first, last, *addr, sz, flags, &dead, 1327 new); 1328 if (entry == NULL) { 1329 error = ENOMEM; 1330 goto unlock; 1331 } 1332 new = NULL; 1333 KDASSERT(entry->start == *addr && entry->end == *addr + sz); 1334 entry->object.uvm_obj = uobj; 1335 entry->offset = uoffset; 1336 entry->protection = prot; 1337 entry->max_protection = maxprot; 1338 entry->inheritance = inherit; 1339 entry->wired_count = 0; 1340 entry->advice = advice; 1341 if (prot & PROT_WRITE) 1342 map->wserial++; 1343 if (flags & UVM_FLAG_STACK) { 1344 entry->etype |= UVM_ET_STACK; 1345 if (flags & UVM_FLAG_UNMAP) 1346 map->sserial++; 1347 } 1348 if (uobj) 1349 entry->etype |= UVM_ET_OBJ; 1350 else if (flags & UVM_FLAG_HOLE) 1351 entry->etype |= UVM_ET_HOLE; 1352 if (flags & UVM_FLAG_NOFAULT) 1353 entry->etype |= UVM_ET_NOFAULT; 1354 if (flags & UVM_FLAG_WC) 1355 entry->etype |= UVM_ET_WC; 1356 if (flags & UVM_FLAG_COPYONW) { 1357 entry->etype |= UVM_ET_COPYONWRITE; 1358 if ((flags & UVM_FLAG_OVERLAY) == 0) 1359 entry->etype |= UVM_ET_NEEDSCOPY; 1360 } 1361 if (flags & UVM_FLAG_CONCEAL) 1362 entry->etype |= UVM_ET_CONCEAL; 1363 if (flags & UVM_FLAG_OVERLAY) { 1364 entry->aref.ar_pageoff = 0; 1365 entry->aref.ar_amap = amap_alloc(sz, M_WAITOK, 0); 1366 } 1367 1368 /* Update map and process statistics. */ 1369 if (!(flags & UVM_FLAG_HOLE)) { 1370 map->size += sz; 1371 if ((map->flags & VM_MAP_ISVMSPACE) && uobj == NULL) { 1372 ((struct vmspace *)map)->vm_dused += 1373 uvmspace_dused(map, *addr, *addr + sz); 1374 } 1375 } 1376 1377 /* 1378 * Try to merge entry. 1379 * 1380 * Userland allocations are kept separated most of the time. 1381 * Forego the effort of merging what most of the time can't be merged 1382 * and only try the merge if it concerns a kernel entry. 1383 */ 1384 if ((flags & UVM_FLAG_NOMERGE) == 0 && 1385 (map->flags & VM_MAP_ISVMSPACE) == 0) 1386 uvm_mapent_tryjoin(map, entry, &dead); 1387 1388 unlock: 1389 vm_map_unlock(map); 1390 1391 /* 1392 * Remove dead entries. 1393 * 1394 * Dead entries may be the result of merging. 1395 * uvm_map_mkentry may also create dead entries, when it attempts to 1396 * destroy free-space entries. 1397 */ 1398 if (map->flags & VM_MAP_INTRSAFE) 1399 uvm_unmap_detach_intrsafe(&dead); 1400 else 1401 uvm_unmap_detach(&dead, 0); 1402 out: 1403 if (new) 1404 uvm_mapent_free(new); 1405 return error; 1406 } 1407 1408 /* 1409 * True iff e1 and e2 can be joined together. 1410 */ 1411 int 1412 uvm_mapent_isjoinable(struct vm_map *map, struct vm_map_entry *e1, 1413 struct vm_map_entry *e2) 1414 { 1415 KDASSERT(e1 != NULL && e2 != NULL); 1416 1417 /* Must be the same entry type and not have free memory between. */ 1418 if (e1->etype != e2->etype || e1->end != e2->start) 1419 return 0; 1420 1421 /* Submaps are never joined. */ 1422 if (UVM_ET_ISSUBMAP(e1)) 1423 return 0; 1424 1425 /* Never merge wired memory. */ 1426 if (VM_MAPENT_ISWIRED(e1) || VM_MAPENT_ISWIRED(e2)) 1427 return 0; 1428 1429 /* Protection, inheritance and advice must be equal. */ 1430 if (e1->protection != e2->protection || 1431 e1->max_protection != e2->max_protection || 1432 e1->inheritance != e2->inheritance || 1433 e1->advice != e2->advice) 1434 return 0; 1435 1436 /* If uvm_object: object itself and offsets within object must match. */ 1437 if (UVM_ET_ISOBJ(e1)) { 1438 if (e1->object.uvm_obj != e2->object.uvm_obj) 1439 return 0; 1440 if (e1->offset + (e1->end - e1->start) != e2->offset) 1441 return 0; 1442 } 1443 1444 /* 1445 * Cannot join shared amaps. 1446 * Note: no need to lock amap to look at refs, since we don't care 1447 * about its exact value. 1448 * If it is 1 (i.e. we have the only reference) it will stay there. 1449 */ 1450 if (e1->aref.ar_amap && amap_refs(e1->aref.ar_amap) != 1) 1451 return 0; 1452 if (e2->aref.ar_amap && amap_refs(e2->aref.ar_amap) != 1) 1453 return 0; 1454 1455 /* Apprently, e1 and e2 match. */ 1456 return 1; 1457 } 1458 1459 /* 1460 * Join support function. 1461 * 1462 * Returns the merged entry on succes. 1463 * Returns NULL if the merge failed. 1464 */ 1465 struct vm_map_entry* 1466 uvm_mapent_merge(struct vm_map *map, struct vm_map_entry *e1, 1467 struct vm_map_entry *e2, struct uvm_map_deadq *dead) 1468 { 1469 struct uvm_addr_state *free; 1470 1471 /* 1472 * Merging is not supported for map entries that 1473 * contain an amap in e1. This should never happen 1474 * anyway, because only kernel entries are merged. 1475 * These do not contain amaps. 1476 * e2 contains no real information in its amap, 1477 * so it can be erased immediately. 1478 */ 1479 KASSERT(e1->aref.ar_amap == NULL); 1480 1481 /* 1482 * Don't drop obj reference: 1483 * uvm_unmap_detach will do this for us. 1484 */ 1485 free = uvm_map_uaddr_e(map, e1); 1486 uvm_mapent_free_remove(map, free, e1); 1487 1488 free = uvm_map_uaddr_e(map, e2); 1489 uvm_mapent_free_remove(map, free, e2); 1490 uvm_mapent_addr_remove(map, e2); 1491 e1->end = e2->end; 1492 e1->guard = e2->guard; 1493 e1->fspace = e2->fspace; 1494 uvm_mapent_free_insert(map, free, e1); 1495 1496 DEAD_ENTRY_PUSH(dead, e2); 1497 return e1; 1498 } 1499 1500 /* 1501 * Attempt forward and backward joining of entry. 1502 * 1503 * Returns entry after joins. 1504 * We are guaranteed that the amap of entry is either non-existent or 1505 * has never been used. 1506 */ 1507 struct vm_map_entry* 1508 uvm_mapent_tryjoin(struct vm_map *map, struct vm_map_entry *entry, 1509 struct uvm_map_deadq *dead) 1510 { 1511 struct vm_map_entry *other; 1512 struct vm_map_entry *merged; 1513 1514 /* Merge with previous entry. */ 1515 other = RBT_PREV(uvm_map_addr, entry); 1516 if (other && uvm_mapent_isjoinable(map, other, entry)) { 1517 merged = uvm_mapent_merge(map, other, entry, dead); 1518 if (merged) 1519 entry = merged; 1520 } 1521 1522 /* 1523 * Merge with next entry. 1524 * 1525 * Because amap can only extend forward and the next entry 1526 * probably contains sensible info, only perform forward merging 1527 * in the absence of an amap. 1528 */ 1529 other = RBT_NEXT(uvm_map_addr, entry); 1530 if (other && entry->aref.ar_amap == NULL && 1531 other->aref.ar_amap == NULL && 1532 uvm_mapent_isjoinable(map, entry, other)) { 1533 merged = uvm_mapent_merge(map, entry, other, dead); 1534 if (merged) 1535 entry = merged; 1536 } 1537 1538 return entry; 1539 } 1540 1541 /* 1542 * Kill entries that are no longer in a map. 1543 */ 1544 void 1545 uvm_unmap_detach(struct uvm_map_deadq *deadq, int flags) 1546 { 1547 struct vm_map_entry *entry, *tmp; 1548 int waitok = flags & UVM_PLA_WAITOK; 1549 1550 TAILQ_FOREACH_SAFE(entry, deadq, dfree.deadq, tmp) { 1551 /* Skip entries for which we have to grab the kernel lock. */ 1552 if (entry->aref.ar_amap || UVM_ET_ISSUBMAP(entry) || 1553 UVM_ET_ISOBJ(entry)) 1554 continue; 1555 1556 TAILQ_REMOVE(deadq, entry, dfree.deadq); 1557 uvm_mapent_free(entry); 1558 } 1559 1560 if (TAILQ_EMPTY(deadq)) 1561 return; 1562 1563 KERNEL_LOCK(); 1564 while ((entry = TAILQ_FIRST(deadq)) != NULL) { 1565 if (waitok) 1566 uvm_pause(); 1567 /* Drop reference to amap, if we've got one. */ 1568 if (entry->aref.ar_amap) 1569 amap_unref(entry->aref.ar_amap, 1570 entry->aref.ar_pageoff, 1571 atop(entry->end - entry->start), 1572 flags & AMAP_REFALL); 1573 1574 /* Drop reference to our backing object, if we've got one. */ 1575 if (UVM_ET_ISSUBMAP(entry)) { 1576 /* ... unlikely to happen, but play it safe */ 1577 uvm_map_deallocate(entry->object.sub_map); 1578 } else if (UVM_ET_ISOBJ(entry) && 1579 entry->object.uvm_obj->pgops->pgo_detach) { 1580 entry->object.uvm_obj->pgops->pgo_detach( 1581 entry->object.uvm_obj); 1582 } 1583 1584 /* Step to next. */ 1585 TAILQ_REMOVE(deadq, entry, dfree.deadq); 1586 uvm_mapent_free(entry); 1587 } 1588 KERNEL_UNLOCK(); 1589 } 1590 1591 void 1592 uvm_unmap_detach_intrsafe(struct uvm_map_deadq *deadq) 1593 { 1594 struct vm_map_entry *entry; 1595 1596 while ((entry = TAILQ_FIRST(deadq)) != NULL) { 1597 KASSERT(entry->aref.ar_amap == NULL); 1598 KASSERT(!UVM_ET_ISSUBMAP(entry)); 1599 KASSERT(!UVM_ET_ISOBJ(entry)); 1600 TAILQ_REMOVE(deadq, entry, dfree.deadq); 1601 uvm_mapent_free(entry); 1602 } 1603 } 1604 1605 /* 1606 * Create and insert new entry. 1607 * 1608 * Returned entry contains new addresses and is inserted properly in the tree. 1609 * first and last are (probably) no longer valid. 1610 */ 1611 struct vm_map_entry* 1612 uvm_map_mkentry(struct vm_map *map, struct vm_map_entry *first, 1613 struct vm_map_entry *last, vaddr_t addr, vsize_t sz, int flags, 1614 struct uvm_map_deadq *dead, struct vm_map_entry *new) 1615 { 1616 struct vm_map_entry *entry, *prev; 1617 struct uvm_addr_state *free; 1618 vaddr_t min, max; /* free space boundaries for new entry */ 1619 1620 KDASSERT(map != NULL); 1621 KDASSERT(first != NULL); 1622 KDASSERT(last != NULL); 1623 KDASSERT(dead != NULL); 1624 KDASSERT(sz > 0); 1625 KDASSERT(addr + sz > addr); 1626 KDASSERT(first->end <= addr && VMMAP_FREE_END(first) > addr); 1627 KDASSERT(last->start < addr + sz && VMMAP_FREE_END(last) >= addr + sz); 1628 KDASSERT(uvm_map_isavail(map, NULL, &first, &last, addr, sz)); 1629 uvm_tree_sanity(map, __FILE__, __LINE__); 1630 1631 min = addr + sz; 1632 max = VMMAP_FREE_END(last); 1633 1634 /* Initialize new entry. */ 1635 if (new == NULL) 1636 entry = uvm_mapent_alloc(map, flags); 1637 else 1638 entry = new; 1639 if (entry == NULL) 1640 return NULL; 1641 entry->offset = 0; 1642 entry->etype = 0; 1643 entry->wired_count = 0; 1644 entry->aref.ar_pageoff = 0; 1645 entry->aref.ar_amap = NULL; 1646 1647 entry->start = addr; 1648 entry->end = min; 1649 entry->guard = 0; 1650 entry->fspace = 0; 1651 1652 /* Reset free space in first. */ 1653 free = uvm_map_uaddr_e(map, first); 1654 uvm_mapent_free_remove(map, free, first); 1655 first->guard = 0; 1656 first->fspace = 0; 1657 1658 /* 1659 * Remove all entries that are fully replaced. 1660 * We are iterating using last in reverse order. 1661 */ 1662 for (; first != last; last = prev) { 1663 prev = RBT_PREV(uvm_map_addr, last); 1664 1665 KDASSERT(last->start == last->end); 1666 free = uvm_map_uaddr_e(map, last); 1667 uvm_mapent_free_remove(map, free, last); 1668 uvm_mapent_addr_remove(map, last); 1669 DEAD_ENTRY_PUSH(dead, last); 1670 } 1671 /* Remove first if it is entirely inside <addr, addr+sz>. */ 1672 if (first->start == addr) { 1673 uvm_mapent_addr_remove(map, first); 1674 DEAD_ENTRY_PUSH(dead, first); 1675 } else { 1676 uvm_map_fix_space(map, first, VMMAP_FREE_START(first), 1677 addr, flags); 1678 } 1679 1680 /* Finally, link in entry. */ 1681 uvm_mapent_addr_insert(map, entry); 1682 uvm_map_fix_space(map, entry, min, max, flags); 1683 1684 uvm_tree_sanity(map, __FILE__, __LINE__); 1685 return entry; 1686 } 1687 1688 1689 /* 1690 * uvm_mapent_alloc: allocate a map entry 1691 */ 1692 struct vm_map_entry * 1693 uvm_mapent_alloc(struct vm_map *map, int flags) 1694 { 1695 struct vm_map_entry *me, *ne; 1696 int pool_flags; 1697 int i; 1698 1699 pool_flags = PR_WAITOK; 1700 if (flags & UVM_FLAG_TRYLOCK) 1701 pool_flags = PR_NOWAIT; 1702 1703 if (map->flags & VM_MAP_INTRSAFE || cold) { 1704 mtx_enter(&uvm_kmapent_mtx); 1705 if (SLIST_EMPTY(&uvm.kentry_free)) { 1706 ne = km_alloc(PAGE_SIZE, &kv_page, &kp_dirty, 1707 &kd_nowait); 1708 if (ne == NULL) 1709 panic("uvm_mapent_alloc: cannot allocate map " 1710 "entry"); 1711 for (i = 0; i < PAGE_SIZE / sizeof(*ne); i++) { 1712 SLIST_INSERT_HEAD(&uvm.kentry_free, 1713 &ne[i], daddrs.addr_kentry); 1714 } 1715 if (ratecheck(&uvm_kmapent_last_warn_time, 1716 &uvm_kmapent_warn_rate)) 1717 printf("uvm_mapent_alloc: out of static " 1718 "map entries\n"); 1719 } 1720 me = SLIST_FIRST(&uvm.kentry_free); 1721 SLIST_REMOVE_HEAD(&uvm.kentry_free, daddrs.addr_kentry); 1722 uvmexp.kmapent++; 1723 mtx_leave(&uvm_kmapent_mtx); 1724 me->flags = UVM_MAP_STATIC; 1725 } else if (map == kernel_map) { 1726 splassert(IPL_NONE); 1727 me = pool_get(&uvm_map_entry_kmem_pool, pool_flags); 1728 if (me == NULL) 1729 goto out; 1730 me->flags = UVM_MAP_KMEM; 1731 } else { 1732 splassert(IPL_NONE); 1733 me = pool_get(&uvm_map_entry_pool, pool_flags); 1734 if (me == NULL) 1735 goto out; 1736 me->flags = 0; 1737 } 1738 1739 if (me != NULL) { 1740 RBT_POISON(uvm_map_addr, me, UVMMAP_DEADBEEF); 1741 } 1742 1743 out: 1744 return(me); 1745 } 1746 1747 /* 1748 * uvm_mapent_free: free map entry 1749 * 1750 * => XXX: static pool for kernel map? 1751 */ 1752 void 1753 uvm_mapent_free(struct vm_map_entry *me) 1754 { 1755 if (me->flags & UVM_MAP_STATIC) { 1756 mtx_enter(&uvm_kmapent_mtx); 1757 SLIST_INSERT_HEAD(&uvm.kentry_free, me, daddrs.addr_kentry); 1758 uvmexp.kmapent--; 1759 mtx_leave(&uvm_kmapent_mtx); 1760 } else if (me->flags & UVM_MAP_KMEM) { 1761 splassert(IPL_NONE); 1762 pool_put(&uvm_map_entry_kmem_pool, me); 1763 } else { 1764 splassert(IPL_NONE); 1765 pool_put(&uvm_map_entry_pool, me); 1766 } 1767 } 1768 1769 /* 1770 * uvm_map_lookup_entry: find map entry at or before an address. 1771 * 1772 * => map must at least be read-locked by caller 1773 * => entry is returned in "entry" 1774 * => return value is true if address is in the returned entry 1775 * ET_HOLE entries are considered to not contain a mapping, ergo FALSE is 1776 * returned for those mappings. 1777 */ 1778 boolean_t 1779 uvm_map_lookup_entry(struct vm_map *map, vaddr_t address, 1780 struct vm_map_entry **entry) 1781 { 1782 *entry = uvm_map_entrybyaddr(&map->addr, address); 1783 return *entry != NULL && !UVM_ET_ISHOLE(*entry) && 1784 (*entry)->start <= address && (*entry)->end > address; 1785 } 1786 1787 /* 1788 * Stack must be in a MAP_STACK entry. PROT_NONE indicates stack not yet 1789 * grown -- then uvm_map_check_region_range() should not cache the entry 1790 * because growth won't be seen. 1791 */ 1792 int 1793 uvm_map_inentry_sp(vm_map_entry_t entry) 1794 { 1795 if ((entry->etype & UVM_ET_STACK) == 0) { 1796 if (entry->protection == PROT_NONE) 1797 return (-1); /* don't update range */ 1798 return (0); 1799 } 1800 return (1); 1801 } 1802 1803 /* 1804 * If a syscall comes from a writeable entry, W^X is violated. 1805 * (Would be nice if we can spot aliasing, which is also kind of bad) 1806 */ 1807 int 1808 uvm_map_inentry_pc(vm_map_entry_t entry) 1809 { 1810 if (entry->protection & PROT_WRITE) 1811 return (0); /* not permitted */ 1812 return (1); 1813 } 1814 1815 int 1816 uvm_map_inentry_recheck(u_long serial, vaddr_t addr, struct p_inentry *ie) 1817 { 1818 return (serial != ie->ie_serial || ie->ie_start == 0 || 1819 addr < ie->ie_start || addr >= ie->ie_end); 1820 } 1821 1822 /* 1823 * Inside a vm_map find the reg address and verify it via function. 1824 * Remember low and high addresses of region if valid and return TRUE, 1825 * else return FALSE. 1826 */ 1827 boolean_t 1828 uvm_map_inentry_fix(struct proc *p, struct p_inentry *ie, vaddr_t addr, 1829 int (*fn)(vm_map_entry_t), u_long serial) 1830 { 1831 vm_map_t map = &p->p_vmspace->vm_map; 1832 vm_map_entry_t entry; 1833 int ret; 1834 1835 if (addr < map->min_offset || addr >= map->max_offset) 1836 return (FALSE); 1837 1838 /* lock map */ 1839 vm_map_lock_read(map); 1840 1841 /* lookup */ 1842 if (!uvm_map_lookup_entry(map, trunc_page(addr), &entry)) { 1843 vm_map_unlock_read(map); 1844 return (FALSE); 1845 } 1846 1847 ret = (*fn)(entry); 1848 if (ret == 0) { 1849 vm_map_unlock_read(map); 1850 return (FALSE); 1851 } else if (ret == 1) { 1852 ie->ie_start = entry->start; 1853 ie->ie_end = entry->end; 1854 ie->ie_serial = serial; 1855 } else { 1856 /* do not update, re-check later */ 1857 } 1858 vm_map_unlock_read(map); 1859 return (TRUE); 1860 } 1861 1862 boolean_t 1863 uvm_map_inentry(struct proc *p, struct p_inentry *ie, vaddr_t addr, 1864 const char *fmt, int (*fn)(vm_map_entry_t), u_long serial) 1865 { 1866 union sigval sv; 1867 boolean_t ok = TRUE; 1868 1869 if (uvm_map_inentry_recheck(serial, addr, ie)) { 1870 KERNEL_LOCK(); 1871 ok = uvm_map_inentry_fix(p, ie, addr, fn, serial); 1872 if (!ok) { 1873 printf(fmt, p->p_p->ps_comm, p->p_p->ps_pid, p->p_tid, 1874 addr, ie->ie_start, ie->ie_end); 1875 sv.sival_ptr = (void *)PROC_PC(p); 1876 trapsignal(p, SIGSEGV, 0, SEGV_ACCERR, sv); 1877 } 1878 KERNEL_UNLOCK(); 1879 } 1880 return (ok); 1881 } 1882 1883 /* 1884 * Check whether the given address range can be converted to a MAP_STACK 1885 * mapping. 1886 * 1887 * Must be called with map locked. 1888 */ 1889 boolean_t 1890 uvm_map_is_stack_remappable(struct vm_map *map, vaddr_t addr, vaddr_t sz) 1891 { 1892 vaddr_t end = addr + sz; 1893 struct vm_map_entry *first, *iter, *prev = NULL; 1894 1895 if (!uvm_map_lookup_entry(map, addr, &first)) { 1896 printf("map stack 0x%lx-0x%lx of map %p failed: no mapping\n", 1897 addr, end, map); 1898 return FALSE; 1899 } 1900 1901 /* 1902 * Check that the address range exists and is contiguous. 1903 */ 1904 for (iter = first; iter != NULL && iter->start < end; 1905 prev = iter, iter = RBT_NEXT(uvm_map_addr, iter)) { 1906 /* 1907 * Make sure that we do not have holes in the range. 1908 */ 1909 #if 0 1910 if (prev != NULL) { 1911 printf("prev->start 0x%lx, prev->end 0x%lx, " 1912 "iter->start 0x%lx, iter->end 0x%lx\n", 1913 prev->start, prev->end, iter->start, iter->end); 1914 } 1915 #endif 1916 1917 if (prev != NULL && prev->end != iter->start) { 1918 printf("map stack 0x%lx-0x%lx of map %p failed: " 1919 "hole in range\n", addr, end, map); 1920 return FALSE; 1921 } 1922 if (iter->start == iter->end || UVM_ET_ISHOLE(iter)) { 1923 printf("map stack 0x%lx-0x%lx of map %p failed: " 1924 "hole in range\n", addr, end, map); 1925 return FALSE; 1926 } 1927 } 1928 1929 return TRUE; 1930 } 1931 1932 /* 1933 * Remap the middle-pages of an existing mapping as a stack range. 1934 * If there exists a previous contiguous mapping with the given range 1935 * [addr, addr + sz), with protection PROT_READ|PROT_WRITE, then the 1936 * mapping is dropped, and a new anon mapping is created and marked as 1937 * a stack. 1938 * 1939 * Must be called with map unlocked. 1940 */ 1941 int 1942 uvm_map_remap_as_stack(struct proc *p, vaddr_t addr, vaddr_t sz) 1943 { 1944 vm_map_t map = &p->p_vmspace->vm_map; 1945 vaddr_t start, end; 1946 int error; 1947 int flags = UVM_MAPFLAG(PROT_READ | PROT_WRITE, 1948 PROT_READ | PROT_WRITE | PROT_EXEC, 1949 MAP_INHERIT_COPY, MADV_NORMAL, 1950 UVM_FLAG_STACK | UVM_FLAG_FIXED | UVM_FLAG_UNMAP | 1951 UVM_FLAG_COPYONW); 1952 1953 start = round_page(addr); 1954 end = trunc_page(addr + sz); 1955 #ifdef MACHINE_STACK_GROWS_UP 1956 if (end == addr + sz) 1957 end -= PAGE_SIZE; 1958 #else 1959 if (start == addr) 1960 start += PAGE_SIZE; 1961 #endif 1962 1963 if (start < map->min_offset || end >= map->max_offset || end < start) 1964 return EINVAL; 1965 1966 error = uvm_mapanon(map, &start, end - start, 0, flags); 1967 if (error != 0) 1968 printf("map stack for pid %d failed\n", p->p_p->ps_pid); 1969 1970 return error; 1971 } 1972 1973 /* 1974 * uvm_map_pie: return a random load address for a PIE executable 1975 * properly aligned. 1976 */ 1977 #ifndef VM_PIE_MAX_ADDR 1978 #define VM_PIE_MAX_ADDR (VM_MAXUSER_ADDRESS / 4) 1979 #endif 1980 1981 #ifndef VM_PIE_MIN_ADDR 1982 #define VM_PIE_MIN_ADDR VM_MIN_ADDRESS 1983 #endif 1984 1985 #ifndef VM_PIE_MIN_ALIGN 1986 #define VM_PIE_MIN_ALIGN PAGE_SIZE 1987 #endif 1988 1989 vaddr_t 1990 uvm_map_pie(vaddr_t align) 1991 { 1992 vaddr_t addr, space, min; 1993 1994 align = MAX(align, VM_PIE_MIN_ALIGN); 1995 1996 /* round up to next alignment */ 1997 min = (VM_PIE_MIN_ADDR + align - 1) & ~(align - 1); 1998 1999 if (align >= VM_PIE_MAX_ADDR || min >= VM_PIE_MAX_ADDR) 2000 return (align); 2001 2002 space = (VM_PIE_MAX_ADDR - min) / align; 2003 space = MIN(space, (u_int32_t)-1); 2004 2005 addr = (vaddr_t)arc4random_uniform((u_int32_t)space) * align; 2006 addr += min; 2007 2008 return (addr); 2009 } 2010 2011 void 2012 uvm_unmap(struct vm_map *map, vaddr_t start, vaddr_t end) 2013 { 2014 struct uvm_map_deadq dead; 2015 2016 KASSERT((start & (vaddr_t)PAGE_MASK) == 0 && 2017 (end & (vaddr_t)PAGE_MASK) == 0); 2018 TAILQ_INIT(&dead); 2019 vm_map_lock(map); 2020 uvm_unmap_remove(map, start, end, &dead, FALSE, TRUE); 2021 vm_map_unlock(map); 2022 2023 if (map->flags & VM_MAP_INTRSAFE) 2024 uvm_unmap_detach_intrsafe(&dead); 2025 else 2026 uvm_unmap_detach(&dead, 0); 2027 } 2028 2029 /* 2030 * Mark entry as free. 2031 * 2032 * entry will be put on the dead list. 2033 * The free space will be merged into the previous or a new entry, 2034 * unless markfree is false. 2035 */ 2036 void 2037 uvm_mapent_mkfree(struct vm_map *map, struct vm_map_entry *entry, 2038 struct vm_map_entry **prev_ptr, struct uvm_map_deadq *dead, 2039 boolean_t markfree) 2040 { 2041 struct uvm_addr_state *free; 2042 struct vm_map_entry *prev; 2043 vaddr_t addr; /* Start of freed range. */ 2044 vaddr_t end; /* End of freed range. */ 2045 2046 prev = *prev_ptr; 2047 if (prev == entry) 2048 *prev_ptr = prev = NULL; 2049 2050 if (prev == NULL || 2051 VMMAP_FREE_END(prev) != entry->start) 2052 prev = RBT_PREV(uvm_map_addr, entry); 2053 2054 /* Entry is describing only free memory and has nothing to drain into. */ 2055 if (prev == NULL && entry->start == entry->end && markfree) { 2056 *prev_ptr = entry; 2057 return; 2058 } 2059 2060 addr = entry->start; 2061 end = VMMAP_FREE_END(entry); 2062 free = uvm_map_uaddr_e(map, entry); 2063 uvm_mapent_free_remove(map, free, entry); 2064 uvm_mapent_addr_remove(map, entry); 2065 DEAD_ENTRY_PUSH(dead, entry); 2066 2067 if (markfree) { 2068 if (prev) { 2069 free = uvm_map_uaddr_e(map, prev); 2070 uvm_mapent_free_remove(map, free, prev); 2071 } 2072 *prev_ptr = uvm_map_fix_space(map, prev, addr, end, 0); 2073 } 2074 } 2075 2076 /* 2077 * Unwire and release referenced amap and object from map entry. 2078 */ 2079 void 2080 uvm_unmap_kill_entry(struct vm_map *map, struct vm_map_entry *entry) 2081 { 2082 /* Unwire removed map entry. */ 2083 if (VM_MAPENT_ISWIRED(entry)) { 2084 KERNEL_LOCK(); 2085 entry->wired_count = 0; 2086 uvm_fault_unwire_locked(map, entry->start, entry->end); 2087 KERNEL_UNLOCK(); 2088 } 2089 2090 /* Entry-type specific code. */ 2091 if (UVM_ET_ISHOLE(entry)) { 2092 /* Nothing to be done for holes. */ 2093 } else if (map->flags & VM_MAP_INTRSAFE) { 2094 KASSERT(vm_map_pmap(map) == pmap_kernel()); 2095 uvm_km_pgremove_intrsafe(entry->start, entry->end); 2096 pmap_kremove(entry->start, entry->end - entry->start); 2097 } else if (UVM_ET_ISOBJ(entry) && 2098 UVM_OBJ_IS_KERN_OBJECT(entry->object.uvm_obj)) { 2099 KASSERT(vm_map_pmap(map) == pmap_kernel()); 2100 /* 2101 * Note: kernel object mappings are currently used in 2102 * two ways: 2103 * [1] "normal" mappings of pages in the kernel object 2104 * [2] uvm_km_valloc'd allocations in which we 2105 * pmap_enter in some non-kernel-object page 2106 * (e.g. vmapbuf). 2107 * 2108 * for case [1], we need to remove the mapping from 2109 * the pmap and then remove the page from the kernel 2110 * object (because, once pages in a kernel object are 2111 * unmapped they are no longer needed, unlike, say, 2112 * a vnode where you might want the data to persist 2113 * until flushed out of a queue). 2114 * 2115 * for case [2], we need to remove the mapping from 2116 * the pmap. there shouldn't be any pages at the 2117 * specified offset in the kernel object [but it 2118 * doesn't hurt to call uvm_km_pgremove just to be 2119 * safe?] 2120 * 2121 * uvm_km_pgremove currently does the following: 2122 * for pages in the kernel object range: 2123 * - drops the swap slot 2124 * - uvm_pagefree the page 2125 * 2126 * note there is version of uvm_km_pgremove() that 2127 * is used for "intrsafe" objects. 2128 */ 2129 /* 2130 * remove mappings from pmap and drop the pages 2131 * from the object. offsets are always relative 2132 * to vm_map_min(kernel_map). 2133 */ 2134 pmap_remove(pmap_kernel(), entry->start, entry->end); 2135 uvm_km_pgremove(entry->object.uvm_obj, 2136 entry->start - vm_map_min(kernel_map), 2137 entry->end - vm_map_min(kernel_map)); 2138 2139 /* 2140 * null out kernel_object reference, we've just 2141 * dropped it 2142 */ 2143 entry->etype &= ~UVM_ET_OBJ; 2144 entry->object.uvm_obj = NULL; /* to be safe */ 2145 } else { 2146 /* remove mappings the standard way. */ 2147 pmap_remove(map->pmap, entry->start, entry->end); 2148 } 2149 } 2150 2151 /* 2152 * Remove all entries from start to end. 2153 * 2154 * If remove_holes, then remove ET_HOLE entries as well. 2155 * If markfree, entry will be properly marked free, otherwise, no replacement 2156 * entry will be put in the tree (corrupting the tree). 2157 */ 2158 void 2159 uvm_unmap_remove(struct vm_map *map, vaddr_t start, vaddr_t end, 2160 struct uvm_map_deadq *dead, boolean_t remove_holes, 2161 boolean_t markfree) 2162 { 2163 struct vm_map_entry *prev_hint, *next, *entry; 2164 2165 start = MAX(start, map->min_offset); 2166 end = MIN(end, map->max_offset); 2167 if (start >= end) 2168 return; 2169 2170 if ((map->flags & VM_MAP_INTRSAFE) == 0) 2171 splassert(IPL_NONE); 2172 else 2173 splassert(IPL_VM); 2174 2175 /* Find first affected entry. */ 2176 entry = uvm_map_entrybyaddr(&map->addr, start); 2177 KDASSERT(entry != NULL && entry->start <= start); 2178 if (entry->end <= start && markfree) 2179 entry = RBT_NEXT(uvm_map_addr, entry); 2180 else 2181 UVM_MAP_CLIP_START(map, entry, start); 2182 2183 /* 2184 * Iterate entries until we reach end address. 2185 * prev_hint hints where the freed space can be appended to. 2186 */ 2187 prev_hint = NULL; 2188 for (; entry != NULL && entry->start < end; entry = next) { 2189 KDASSERT(entry->start >= start); 2190 if (entry->end > end || !markfree) 2191 UVM_MAP_CLIP_END(map, entry, end); 2192 KDASSERT(entry->start >= start && entry->end <= end); 2193 next = RBT_NEXT(uvm_map_addr, entry); 2194 2195 /* Don't remove holes unless asked to do so. */ 2196 if (UVM_ET_ISHOLE(entry)) { 2197 if (!remove_holes) { 2198 prev_hint = entry; 2199 continue; 2200 } 2201 } 2202 2203 /* A stack has been removed.. */ 2204 if (UVM_ET_ISSTACK(entry) && (map->flags & VM_MAP_ISVMSPACE)) 2205 map->sserial++; 2206 2207 /* Kill entry. */ 2208 uvm_unmap_kill_entry(map, entry); 2209 2210 /* Update space usage. */ 2211 if ((map->flags & VM_MAP_ISVMSPACE) && 2212 entry->object.uvm_obj == NULL && 2213 !UVM_ET_ISHOLE(entry)) { 2214 ((struct vmspace *)map)->vm_dused -= 2215 uvmspace_dused(map, entry->start, entry->end); 2216 } 2217 if (!UVM_ET_ISHOLE(entry)) 2218 map->size -= entry->end - entry->start; 2219 2220 /* Actual removal of entry. */ 2221 uvm_mapent_mkfree(map, entry, &prev_hint, dead, markfree); 2222 } 2223 2224 pmap_update(vm_map_pmap(map)); 2225 2226 #ifdef VMMAP_DEBUG 2227 if (markfree) { 2228 for (entry = uvm_map_entrybyaddr(&map->addr, start); 2229 entry != NULL && entry->start < end; 2230 entry = RBT_NEXT(uvm_map_addr, entry)) { 2231 KDASSERT(entry->end <= start || 2232 entry->start == entry->end || 2233 UVM_ET_ISHOLE(entry)); 2234 } 2235 } else { 2236 vaddr_t a; 2237 for (a = start; a < end; a += PAGE_SIZE) 2238 KDASSERT(uvm_map_entrybyaddr(&map->addr, a) == NULL); 2239 } 2240 #endif 2241 } 2242 2243 /* 2244 * Mark all entries from first until end (exclusive) as pageable. 2245 * 2246 * Lock must be exclusive on entry and will not be touched. 2247 */ 2248 void 2249 uvm_map_pageable_pgon(struct vm_map *map, struct vm_map_entry *first, 2250 struct vm_map_entry *end, vaddr_t start_addr, vaddr_t end_addr) 2251 { 2252 struct vm_map_entry *iter; 2253 2254 for (iter = first; iter != end; 2255 iter = RBT_NEXT(uvm_map_addr, iter)) { 2256 KDASSERT(iter->start >= start_addr && iter->end <= end_addr); 2257 if (!VM_MAPENT_ISWIRED(iter) || UVM_ET_ISHOLE(iter)) 2258 continue; 2259 2260 iter->wired_count = 0; 2261 uvm_fault_unwire_locked(map, iter->start, iter->end); 2262 } 2263 } 2264 2265 /* 2266 * Mark all entries from first until end (exclusive) as wired. 2267 * 2268 * Lockflags determines the lock state on return from this function. 2269 * Lock must be exclusive on entry. 2270 */ 2271 int 2272 uvm_map_pageable_wire(struct vm_map *map, struct vm_map_entry *first, 2273 struct vm_map_entry *end, vaddr_t start_addr, vaddr_t end_addr, 2274 int lockflags) 2275 { 2276 struct vm_map_entry *iter; 2277 #ifdef DIAGNOSTIC 2278 unsigned int timestamp_save; 2279 #endif 2280 int error; 2281 2282 /* 2283 * Wire pages in two passes: 2284 * 2285 * 1: holding the write lock, we create any anonymous maps that need 2286 * to be created. then we clip each map entry to the region to 2287 * be wired and increment its wiring count. 2288 * 2289 * 2: we downgrade to a read lock, and call uvm_fault_wire to fault 2290 * in the pages for any newly wired area (wired_count == 1). 2291 * 2292 * downgrading to a read lock for uvm_fault_wire avoids a possible 2293 * deadlock with another thread that may have faulted on one of 2294 * the pages to be wired (it would mark the page busy, blocking 2295 * us, then in turn block on the map lock that we hold). 2296 * because we keep the read lock on the map, the copy-on-write 2297 * status of the entries we modify here cannot change. 2298 */ 2299 for (iter = first; iter != end; 2300 iter = RBT_NEXT(uvm_map_addr, iter)) { 2301 KDASSERT(iter->start >= start_addr && iter->end <= end_addr); 2302 if (UVM_ET_ISHOLE(iter) || iter->start == iter->end || 2303 iter->protection == PROT_NONE) 2304 continue; 2305 2306 /* 2307 * Perform actions of vm_map_lookup that need the write lock. 2308 * - create an anonymous map for copy-on-write 2309 * - anonymous map for zero-fill 2310 * Skip submaps. 2311 */ 2312 if (!VM_MAPENT_ISWIRED(iter) && !UVM_ET_ISSUBMAP(iter) && 2313 UVM_ET_ISNEEDSCOPY(iter) && 2314 ((iter->protection & PROT_WRITE) || 2315 iter->object.uvm_obj == NULL)) { 2316 amap_copy(map, iter, M_WAITOK, 2317 UVM_ET_ISSTACK(iter) ? FALSE : TRUE, 2318 iter->start, iter->end); 2319 } 2320 iter->wired_count++; 2321 } 2322 2323 /* 2324 * Pass 2. 2325 */ 2326 #ifdef DIAGNOSTIC 2327 timestamp_save = map->timestamp; 2328 #endif 2329 vm_map_busy(map); 2330 vm_map_downgrade(map); 2331 2332 error = 0; 2333 for (iter = first; error == 0 && iter != end; 2334 iter = RBT_NEXT(uvm_map_addr, iter)) { 2335 if (UVM_ET_ISHOLE(iter) || iter->start == iter->end || 2336 iter->protection == PROT_NONE) 2337 continue; 2338 2339 error = uvm_fault_wire(map, iter->start, iter->end, 2340 iter->protection); 2341 } 2342 2343 if (error) { 2344 /* 2345 * uvm_fault_wire failure 2346 * 2347 * Reacquire lock and undo our work. 2348 */ 2349 vm_map_upgrade(map); 2350 vm_map_unbusy(map); 2351 #ifdef DIAGNOSTIC 2352 if (timestamp_save != map->timestamp) 2353 panic("uvm_map_pageable_wire: stale map"); 2354 #endif 2355 2356 /* 2357 * first is no longer needed to restart loops. 2358 * Use it as iterator to unmap successful mappings. 2359 */ 2360 for (; first != iter; 2361 first = RBT_NEXT(uvm_map_addr, first)) { 2362 if (UVM_ET_ISHOLE(first) || 2363 first->start == first->end || 2364 first->protection == PROT_NONE) 2365 continue; 2366 2367 first->wired_count--; 2368 if (!VM_MAPENT_ISWIRED(first)) { 2369 uvm_fault_unwire_locked(map, 2370 iter->start, iter->end); 2371 } 2372 } 2373 2374 /* decrease counter in the rest of the entries */ 2375 for (; iter != end; 2376 iter = RBT_NEXT(uvm_map_addr, iter)) { 2377 if (UVM_ET_ISHOLE(iter) || iter->start == iter->end || 2378 iter->protection == PROT_NONE) 2379 continue; 2380 2381 iter->wired_count--; 2382 } 2383 2384 if ((lockflags & UVM_LK_EXIT) == 0) 2385 vm_map_unlock(map); 2386 return error; 2387 } 2388 2389 /* We are currently holding a read lock. */ 2390 if ((lockflags & UVM_LK_EXIT) == 0) { 2391 vm_map_unbusy(map); 2392 vm_map_unlock_read(map); 2393 } else { 2394 vm_map_upgrade(map); 2395 vm_map_unbusy(map); 2396 #ifdef DIAGNOSTIC 2397 if (timestamp_save != map->timestamp) 2398 panic("uvm_map_pageable_wire: stale map"); 2399 #endif 2400 } 2401 return 0; 2402 } 2403 2404 /* 2405 * uvm_map_pageable: set pageability of a range in a map. 2406 * 2407 * Flags: 2408 * UVM_LK_ENTER: map is already locked by caller 2409 * UVM_LK_EXIT: don't unlock map on exit 2410 * 2411 * The full range must be in use (entries may not have fspace != 0). 2412 * UVM_ET_HOLE counts as unmapped. 2413 */ 2414 int 2415 uvm_map_pageable(struct vm_map *map, vaddr_t start, vaddr_t end, 2416 boolean_t new_pageable, int lockflags) 2417 { 2418 struct vm_map_entry *first, *last, *tmp; 2419 int error; 2420 2421 start = trunc_page(start); 2422 end = round_page(end); 2423 2424 if (start > end) 2425 return EINVAL; 2426 if (start == end) 2427 return 0; /* nothing to do */ 2428 if (start < map->min_offset) 2429 return EFAULT; /* why? see first XXX below */ 2430 if (end > map->max_offset) 2431 return EINVAL; /* why? see second XXX below */ 2432 2433 KASSERT(map->flags & VM_MAP_PAGEABLE); 2434 if ((lockflags & UVM_LK_ENTER) == 0) 2435 vm_map_lock(map); 2436 2437 /* 2438 * Find first entry. 2439 * 2440 * Initial test on start is different, because of the different 2441 * error returned. Rest is tested further down. 2442 */ 2443 first = uvm_map_entrybyaddr(&map->addr, start); 2444 if (first->end <= start || UVM_ET_ISHOLE(first)) { 2445 /* 2446 * XXX if the first address is not mapped, it is EFAULT? 2447 */ 2448 error = EFAULT; 2449 goto out; 2450 } 2451 2452 /* Check that the range has no holes. */ 2453 for (last = first; last != NULL && last->start < end; 2454 last = RBT_NEXT(uvm_map_addr, last)) { 2455 if (UVM_ET_ISHOLE(last) || 2456 (last->end < end && VMMAP_FREE_END(last) != last->end)) { 2457 /* 2458 * XXX unmapped memory in range, why is it EINVAL 2459 * instead of EFAULT? 2460 */ 2461 error = EINVAL; 2462 goto out; 2463 } 2464 } 2465 2466 /* 2467 * Last ended at the first entry after the range. 2468 * Move back one step. 2469 * 2470 * Note that last may be NULL. 2471 */ 2472 if (last == NULL) { 2473 last = RBT_MAX(uvm_map_addr, &map->addr); 2474 if (last->end < end) { 2475 error = EINVAL; 2476 goto out; 2477 } 2478 } else { 2479 KASSERT(last != first); 2480 last = RBT_PREV(uvm_map_addr, last); 2481 } 2482 2483 /* Wire/unwire pages here. */ 2484 if (new_pageable) { 2485 /* 2486 * Mark pageable. 2487 * entries that are not wired are untouched. 2488 */ 2489 if (VM_MAPENT_ISWIRED(first)) 2490 UVM_MAP_CLIP_START(map, first, start); 2491 /* 2492 * Split last at end. 2493 * Make tmp be the first entry after what is to be touched. 2494 * If last is not wired, don't touch it. 2495 */ 2496 if (VM_MAPENT_ISWIRED(last)) { 2497 UVM_MAP_CLIP_END(map, last, end); 2498 tmp = RBT_NEXT(uvm_map_addr, last); 2499 } else 2500 tmp = last; 2501 2502 uvm_map_pageable_pgon(map, first, tmp, start, end); 2503 error = 0; 2504 2505 out: 2506 if ((lockflags & UVM_LK_EXIT) == 0) 2507 vm_map_unlock(map); 2508 return error; 2509 } else { 2510 /* 2511 * Mark entries wired. 2512 * entries are always touched (because recovery needs this). 2513 */ 2514 if (!VM_MAPENT_ISWIRED(first)) 2515 UVM_MAP_CLIP_START(map, first, start); 2516 /* 2517 * Split last at end. 2518 * Make tmp be the first entry after what is to be touched. 2519 * If last is not wired, don't touch it. 2520 */ 2521 if (!VM_MAPENT_ISWIRED(last)) { 2522 UVM_MAP_CLIP_END(map, last, end); 2523 tmp = RBT_NEXT(uvm_map_addr, last); 2524 } else 2525 tmp = last; 2526 2527 return uvm_map_pageable_wire(map, first, tmp, start, end, 2528 lockflags); 2529 } 2530 } 2531 2532 /* 2533 * uvm_map_pageable_all: special case of uvm_map_pageable - affects 2534 * all mapped regions. 2535 * 2536 * Map must not be locked. 2537 * If no flags are specified, all ragions are unwired. 2538 */ 2539 int 2540 uvm_map_pageable_all(struct vm_map *map, int flags, vsize_t limit) 2541 { 2542 vsize_t size; 2543 struct vm_map_entry *iter; 2544 2545 KASSERT(map->flags & VM_MAP_PAGEABLE); 2546 vm_map_lock(map); 2547 2548 if (flags == 0) { 2549 uvm_map_pageable_pgon(map, RBT_MIN(uvm_map_addr, &map->addr), 2550 NULL, map->min_offset, map->max_offset); 2551 2552 vm_map_modflags(map, 0, VM_MAP_WIREFUTURE); 2553 vm_map_unlock(map); 2554 return 0; 2555 } 2556 2557 if (flags & MCL_FUTURE) 2558 vm_map_modflags(map, VM_MAP_WIREFUTURE, 0); 2559 if (!(flags & MCL_CURRENT)) { 2560 vm_map_unlock(map); 2561 return 0; 2562 } 2563 2564 /* 2565 * Count number of pages in all non-wired entries. 2566 * If the number exceeds the limit, abort. 2567 */ 2568 size = 0; 2569 RBT_FOREACH(iter, uvm_map_addr, &map->addr) { 2570 if (VM_MAPENT_ISWIRED(iter) || UVM_ET_ISHOLE(iter)) 2571 continue; 2572 2573 size += iter->end - iter->start; 2574 } 2575 2576 if (atop(size) + uvmexp.wired > uvmexp.wiredmax) { 2577 vm_map_unlock(map); 2578 return ENOMEM; 2579 } 2580 2581 /* XXX non-pmap_wired_count case must be handled by caller */ 2582 #ifdef pmap_wired_count 2583 if (limit != 0 && 2584 size + ptoa(pmap_wired_count(vm_map_pmap(map))) > limit) { 2585 vm_map_unlock(map); 2586 return ENOMEM; 2587 } 2588 #endif 2589 2590 /* 2591 * uvm_map_pageable_wire will release lcok 2592 */ 2593 return uvm_map_pageable_wire(map, RBT_MIN(uvm_map_addr, &map->addr), 2594 NULL, map->min_offset, map->max_offset, 0); 2595 } 2596 2597 /* 2598 * Initialize map. 2599 * 2600 * Allocates sufficient entries to describe the free memory in the map. 2601 */ 2602 void 2603 uvm_map_setup(struct vm_map *map, vaddr_t min, vaddr_t max, int flags) 2604 { 2605 int i; 2606 2607 KASSERT((min & (vaddr_t)PAGE_MASK) == 0); 2608 KASSERT((max & (vaddr_t)PAGE_MASK) == 0 || 2609 (max & (vaddr_t)PAGE_MASK) == (vaddr_t)PAGE_MASK); 2610 2611 /* 2612 * Update parameters. 2613 * 2614 * This code handles (vaddr_t)-1 and other page mask ending addresses 2615 * properly. 2616 * We lose the top page if the full virtual address space is used. 2617 */ 2618 if (max & (vaddr_t)PAGE_MASK) { 2619 max += 1; 2620 if (max == 0) /* overflow */ 2621 max -= PAGE_SIZE; 2622 } 2623 2624 RBT_INIT(uvm_map_addr, &map->addr); 2625 map->uaddr_exe = NULL; 2626 for (i = 0; i < nitems(map->uaddr_any); ++i) 2627 map->uaddr_any[i] = NULL; 2628 map->uaddr_brk_stack = NULL; 2629 2630 map->size = 0; 2631 map->ref_count = 0; 2632 map->min_offset = min; 2633 map->max_offset = max; 2634 map->b_start = map->b_end = 0; /* Empty brk() area by default. */ 2635 map->s_start = map->s_end = 0; /* Empty stack area by default. */ 2636 map->flags = flags; 2637 map->timestamp = 0; 2638 rw_init_flags(&map->lock, "vmmaplk", RWL_DUPOK); 2639 mtx_init(&map->mtx, IPL_VM); 2640 mtx_init(&map->flags_lock, IPL_VM); 2641 2642 /* Configure the allocators. */ 2643 if (flags & VM_MAP_ISVMSPACE) 2644 uvm_map_setup_md(map); 2645 else 2646 map->uaddr_any[3] = &uaddr_kbootstrap; 2647 2648 /* 2649 * Fill map entries. 2650 * We do not need to write-lock the map here because only the current 2651 * thread sees it right now. Initialize ref_count to 0 above to avoid 2652 * bogus triggering of lock-not-held assertions. 2653 */ 2654 uvm_map_setup_entries(map); 2655 uvm_tree_sanity(map, __FILE__, __LINE__); 2656 map->ref_count = 1; 2657 } 2658 2659 /* 2660 * Destroy the map. 2661 * 2662 * This is the inverse operation to uvm_map_setup. 2663 */ 2664 void 2665 uvm_map_teardown(struct vm_map *map) 2666 { 2667 struct uvm_map_deadq dead_entries; 2668 struct vm_map_entry *entry, *tmp; 2669 #ifdef VMMAP_DEBUG 2670 size_t numq, numt; 2671 #endif 2672 int i; 2673 2674 KERNEL_ASSERT_LOCKED(); 2675 KERNEL_UNLOCK(); 2676 KERNEL_ASSERT_UNLOCKED(); 2677 2678 KASSERT((map->flags & VM_MAP_INTRSAFE) == 0); 2679 2680 /* Remove address selectors. */ 2681 uvm_addr_destroy(map->uaddr_exe); 2682 map->uaddr_exe = NULL; 2683 for (i = 0; i < nitems(map->uaddr_any); i++) { 2684 uvm_addr_destroy(map->uaddr_any[i]); 2685 map->uaddr_any[i] = NULL; 2686 } 2687 uvm_addr_destroy(map->uaddr_brk_stack); 2688 map->uaddr_brk_stack = NULL; 2689 2690 /* 2691 * Remove entries. 2692 * 2693 * The following is based on graph breadth-first search. 2694 * 2695 * In color terms: 2696 * - the dead_entries set contains all nodes that are reachable 2697 * (i.e. both the black and the grey nodes) 2698 * - any entry not in dead_entries is white 2699 * - any entry that appears in dead_entries before entry, 2700 * is black, the rest is grey. 2701 * The set [entry, end] is also referred to as the wavefront. 2702 * 2703 * Since the tree is always a fully connected graph, the breadth-first 2704 * search guarantees that each vmmap_entry is visited exactly once. 2705 * The vm_map is broken down in linear time. 2706 */ 2707 TAILQ_INIT(&dead_entries); 2708 if ((entry = RBT_ROOT(uvm_map_addr, &map->addr)) != NULL) 2709 DEAD_ENTRY_PUSH(&dead_entries, entry); 2710 while (entry != NULL) { 2711 sched_pause(yield); 2712 uvm_unmap_kill_entry(map, entry); 2713 if ((tmp = RBT_LEFT(uvm_map_addr, entry)) != NULL) 2714 DEAD_ENTRY_PUSH(&dead_entries, tmp); 2715 if ((tmp = RBT_RIGHT(uvm_map_addr, entry)) != NULL) 2716 DEAD_ENTRY_PUSH(&dead_entries, tmp); 2717 /* Update wave-front. */ 2718 entry = TAILQ_NEXT(entry, dfree.deadq); 2719 } 2720 2721 #ifdef VMMAP_DEBUG 2722 numt = numq = 0; 2723 RBT_FOREACH(entry, uvm_map_addr, &map->addr) 2724 numt++; 2725 TAILQ_FOREACH(entry, &dead_entries, dfree.deadq) 2726 numq++; 2727 KASSERT(numt == numq); 2728 #endif 2729 uvm_unmap_detach(&dead_entries, UVM_PLA_WAITOK); 2730 2731 KERNEL_LOCK(); 2732 2733 pmap_destroy(map->pmap); 2734 map->pmap = NULL; 2735 } 2736 2737 /* 2738 * Populate map with free-memory entries. 2739 * 2740 * Map must be initialized and empty. 2741 */ 2742 void 2743 uvm_map_setup_entries(struct vm_map *map) 2744 { 2745 KDASSERT(RBT_EMPTY(uvm_map_addr, &map->addr)); 2746 2747 uvm_map_fix_space(map, NULL, map->min_offset, map->max_offset, 0); 2748 } 2749 2750 /* 2751 * Split entry at given address. 2752 * 2753 * orig: entry that is to be split. 2754 * next: a newly allocated map entry that is not linked. 2755 * split: address at which the split is done. 2756 */ 2757 void 2758 uvm_map_splitentry(struct vm_map *map, struct vm_map_entry *orig, 2759 struct vm_map_entry *next, vaddr_t split) 2760 { 2761 struct uvm_addr_state *free, *free_before; 2762 vsize_t adj; 2763 2764 if ((split & PAGE_MASK) != 0) { 2765 panic("uvm_map_splitentry: split address 0x%lx " 2766 "not on page boundary!", split); 2767 } 2768 KDASSERT(map != NULL && orig != NULL && next != NULL); 2769 uvm_tree_sanity(map, __FILE__, __LINE__); 2770 KASSERT(orig->start < split && VMMAP_FREE_END(orig) > split); 2771 2772 #ifdef VMMAP_DEBUG 2773 KDASSERT(RBT_FIND(uvm_map_addr, &map->addr, orig) == orig); 2774 KDASSERT(RBT_FIND(uvm_map_addr, &map->addr, next) != next); 2775 #endif /* VMMAP_DEBUG */ 2776 2777 /* 2778 * Free space will change, unlink from free space tree. 2779 */ 2780 free = uvm_map_uaddr_e(map, orig); 2781 uvm_mapent_free_remove(map, free, orig); 2782 2783 adj = split - orig->start; 2784 2785 uvm_mapent_copy(orig, next); 2786 if (split >= orig->end) { 2787 next->etype = 0; 2788 next->offset = 0; 2789 next->wired_count = 0; 2790 next->start = next->end = split; 2791 next->guard = 0; 2792 next->fspace = VMMAP_FREE_END(orig) - split; 2793 next->aref.ar_amap = NULL; 2794 next->aref.ar_pageoff = 0; 2795 orig->guard = MIN(orig->guard, split - orig->end); 2796 orig->fspace = split - VMMAP_FREE_START(orig); 2797 } else { 2798 orig->fspace = 0; 2799 orig->guard = 0; 2800 orig->end = next->start = split; 2801 2802 if (next->aref.ar_amap) { 2803 KERNEL_LOCK(); 2804 amap_splitref(&orig->aref, &next->aref, adj); 2805 KERNEL_UNLOCK(); 2806 } 2807 if (UVM_ET_ISSUBMAP(orig)) { 2808 uvm_map_reference(next->object.sub_map); 2809 next->offset += adj; 2810 } else if (UVM_ET_ISOBJ(orig)) { 2811 if (next->object.uvm_obj->pgops && 2812 next->object.uvm_obj->pgops->pgo_reference) { 2813 KERNEL_LOCK(); 2814 next->object.uvm_obj->pgops->pgo_reference( 2815 next->object.uvm_obj); 2816 KERNEL_UNLOCK(); 2817 } 2818 next->offset += adj; 2819 } 2820 } 2821 2822 /* 2823 * Link next into address tree. 2824 * Link orig and next into free-space tree. 2825 * 2826 * Don't insert 'next' into the addr tree until orig has been linked, 2827 * in case the free-list looks at adjecent entries in the addr tree 2828 * for its decisions. 2829 */ 2830 if (orig->fspace > 0) 2831 free_before = free; 2832 else 2833 free_before = uvm_map_uaddr_e(map, orig); 2834 uvm_mapent_free_insert(map, free_before, orig); 2835 uvm_mapent_addr_insert(map, next); 2836 uvm_mapent_free_insert(map, free, next); 2837 2838 uvm_tree_sanity(map, __FILE__, __LINE__); 2839 } 2840 2841 2842 #ifdef VMMAP_DEBUG 2843 2844 void 2845 uvm_tree_assert(struct vm_map *map, int test, char *test_str, 2846 char *file, int line) 2847 { 2848 char* map_special; 2849 2850 if (test) 2851 return; 2852 2853 if (map == kernel_map) 2854 map_special = " (kernel_map)"; 2855 else if (map == kmem_map) 2856 map_special = " (kmem_map)"; 2857 else 2858 map_special = ""; 2859 panic("uvm_tree_sanity %p%s (%s %d): %s", map, map_special, file, 2860 line, test_str); 2861 } 2862 2863 /* 2864 * Check that map is sane. 2865 */ 2866 void 2867 uvm_tree_sanity(struct vm_map *map, char *file, int line) 2868 { 2869 struct vm_map_entry *iter; 2870 vaddr_t addr; 2871 vaddr_t min, max, bound; /* Bounds checker. */ 2872 struct uvm_addr_state *free; 2873 2874 addr = vm_map_min(map); 2875 RBT_FOREACH(iter, uvm_map_addr, &map->addr) { 2876 /* 2877 * Valid start, end. 2878 * Catch overflow for end+fspace. 2879 */ 2880 UVM_ASSERT(map, iter->end >= iter->start, file, line); 2881 UVM_ASSERT(map, VMMAP_FREE_END(iter) >= iter->end, file, line); 2882 2883 /* May not be empty. */ 2884 UVM_ASSERT(map, iter->start < VMMAP_FREE_END(iter), 2885 file, line); 2886 2887 /* Addresses for entry must lie within map boundaries. */ 2888 UVM_ASSERT(map, iter->start >= vm_map_min(map) && 2889 VMMAP_FREE_END(iter) <= vm_map_max(map), file, line); 2890 2891 /* Tree may not have gaps. */ 2892 UVM_ASSERT(map, iter->start == addr, file, line); 2893 addr = VMMAP_FREE_END(iter); 2894 2895 /* 2896 * Free space may not cross boundaries, unless the same 2897 * free list is used on both sides of the border. 2898 */ 2899 min = VMMAP_FREE_START(iter); 2900 max = VMMAP_FREE_END(iter); 2901 2902 while (min < max && 2903 (bound = uvm_map_boundary(map, min, max)) != max) { 2904 UVM_ASSERT(map, 2905 uvm_map_uaddr(map, bound - 1) == 2906 uvm_map_uaddr(map, bound), 2907 file, line); 2908 min = bound; 2909 } 2910 2911 free = uvm_map_uaddr_e(map, iter); 2912 if (free) { 2913 UVM_ASSERT(map, (iter->etype & UVM_ET_FREEMAPPED) != 0, 2914 file, line); 2915 } else { 2916 UVM_ASSERT(map, (iter->etype & UVM_ET_FREEMAPPED) == 0, 2917 file, line); 2918 } 2919 } 2920 UVM_ASSERT(map, addr == vm_map_max(map), file, line); 2921 } 2922 2923 void 2924 uvm_tree_size_chk(struct vm_map *map, char *file, int line) 2925 { 2926 struct vm_map_entry *iter; 2927 vsize_t size; 2928 2929 size = 0; 2930 RBT_FOREACH(iter, uvm_map_addr, &map->addr) { 2931 if (!UVM_ET_ISHOLE(iter)) 2932 size += iter->end - iter->start; 2933 } 2934 2935 if (map->size != size) 2936 printf("map size = 0x%lx, should be 0x%lx\n", map->size, size); 2937 UVM_ASSERT(map, map->size == size, file, line); 2938 2939 vmspace_validate(map); 2940 } 2941 2942 /* 2943 * This function validates the statistics on vmspace. 2944 */ 2945 void 2946 vmspace_validate(struct vm_map *map) 2947 { 2948 struct vmspace *vm; 2949 struct vm_map_entry *iter; 2950 vaddr_t imin, imax; 2951 vaddr_t stack_begin, stack_end; /* Position of stack. */ 2952 vsize_t stack, heap; /* Measured sizes. */ 2953 2954 if (!(map->flags & VM_MAP_ISVMSPACE)) 2955 return; 2956 2957 vm = (struct vmspace *)map; 2958 stack_begin = MIN((vaddr_t)vm->vm_maxsaddr, (vaddr_t)vm->vm_minsaddr); 2959 stack_end = MAX((vaddr_t)vm->vm_maxsaddr, (vaddr_t)vm->vm_minsaddr); 2960 2961 stack = heap = 0; 2962 RBT_FOREACH(iter, uvm_map_addr, &map->addr) { 2963 imin = imax = iter->start; 2964 2965 if (UVM_ET_ISHOLE(iter) || iter->object.uvm_obj != NULL) 2966 continue; 2967 2968 /* 2969 * Update stack, heap. 2970 * Keep in mind that (theoretically) the entries of 2971 * userspace and stack may be joined. 2972 */ 2973 while (imin != iter->end) { 2974 /* 2975 * Set imax to the first boundary crossed between 2976 * imin and stack addresses. 2977 */ 2978 imax = iter->end; 2979 if (imin < stack_begin && imax > stack_begin) 2980 imax = stack_begin; 2981 else if (imin < stack_end && imax > stack_end) 2982 imax = stack_end; 2983 2984 if (imin >= stack_begin && imin < stack_end) 2985 stack += imax - imin; 2986 else 2987 heap += imax - imin; 2988 imin = imax; 2989 } 2990 } 2991 2992 heap >>= PAGE_SHIFT; 2993 if (heap != vm->vm_dused) { 2994 printf("vmspace stack range: 0x%lx-0x%lx\n", 2995 stack_begin, stack_end); 2996 panic("vmspace_validate: vmspace.vm_dused invalid, " 2997 "expected %ld pgs, got %ld pgs in map %p", 2998 heap, vm->vm_dused, 2999 map); 3000 } 3001 } 3002 3003 #endif /* VMMAP_DEBUG */ 3004 3005 /* 3006 * uvm_map_init: init mapping system at boot time. note that we allocate 3007 * and init the static pool of structs vm_map_entry for the kernel here. 3008 */ 3009 void 3010 uvm_map_init(void) 3011 { 3012 static struct vm_map_entry kernel_map_entry[MAX_KMAPENT]; 3013 int lcv; 3014 3015 /* now set up static pool of kernel map entries ... */ 3016 mtx_init(&uvm_kmapent_mtx, IPL_VM); 3017 SLIST_INIT(&uvm.kentry_free); 3018 for (lcv = 0 ; lcv < MAX_KMAPENT ; lcv++) { 3019 SLIST_INSERT_HEAD(&uvm.kentry_free, 3020 &kernel_map_entry[lcv], daddrs.addr_kentry); 3021 } 3022 3023 /* initialize the map-related pools. */ 3024 pool_init(&uvm_vmspace_pool, sizeof(struct vmspace), 0, 3025 IPL_NONE, PR_WAITOK, "vmsppl", NULL); 3026 pool_init(&uvm_map_entry_pool, sizeof(struct vm_map_entry), 0, 3027 IPL_VM, PR_WAITOK, "vmmpepl", NULL); 3028 pool_init(&uvm_map_entry_kmem_pool, sizeof(struct vm_map_entry), 0, 3029 IPL_VM, 0, "vmmpekpl", NULL); 3030 pool_sethiwat(&uvm_map_entry_pool, 8192); 3031 3032 uvm_addr_init(); 3033 } 3034 3035 #if defined(DDB) 3036 3037 /* 3038 * DDB hooks 3039 */ 3040 3041 /* 3042 * uvm_map_printit: actually prints the map 3043 */ 3044 void 3045 uvm_map_printit(struct vm_map *map, boolean_t full, 3046 int (*pr)(const char *, ...)) 3047 { 3048 struct vmspace *vm; 3049 struct vm_map_entry *entry; 3050 struct uvm_addr_state *free; 3051 int in_free, i; 3052 char buf[8]; 3053 3054 (*pr)("MAP %p: [0x%lx->0x%lx]\n", map, map->min_offset,map->max_offset); 3055 (*pr)("\tbrk() allocate range: 0x%lx-0x%lx\n", 3056 map->b_start, map->b_end); 3057 (*pr)("\tstack allocate range: 0x%lx-0x%lx\n", 3058 map->s_start, map->s_end); 3059 (*pr)("\tsz=%u, ref=%d, version=%u, flags=0x%x\n", 3060 map->size, map->ref_count, map->timestamp, 3061 map->flags); 3062 (*pr)("\tpmap=%p(resident=%d)\n", map->pmap, 3063 pmap_resident_count(map->pmap)); 3064 3065 /* struct vmspace handling. */ 3066 if (map->flags & VM_MAP_ISVMSPACE) { 3067 vm = (struct vmspace *)map; 3068 3069 (*pr)("\tvm_refcnt=%d vm_shm=%p vm_rssize=%u vm_swrss=%u\n", 3070 vm->vm_refcnt, vm->vm_shm, vm->vm_rssize, vm->vm_swrss); 3071 (*pr)("\tvm_tsize=%u vm_dsize=%u\n", 3072 vm->vm_tsize, vm->vm_dsize); 3073 (*pr)("\tvm_taddr=%p vm_daddr=%p\n", 3074 vm->vm_taddr, vm->vm_daddr); 3075 (*pr)("\tvm_maxsaddr=%p vm_minsaddr=%p\n", 3076 vm->vm_maxsaddr, vm->vm_minsaddr); 3077 } 3078 3079 if (!full) 3080 goto print_uaddr; 3081 RBT_FOREACH(entry, uvm_map_addr, &map->addr) { 3082 (*pr)(" - %p: 0x%lx->0x%lx: obj=%p/0x%llx, amap=%p/%d\n", 3083 entry, entry->start, entry->end, entry->object.uvm_obj, 3084 (long long)entry->offset, entry->aref.ar_amap, 3085 entry->aref.ar_pageoff); 3086 (*pr)("\tsubmap=%c, cow=%c, nc=%c, stack=%c, prot(max)=%d/%d, inh=%d, " 3087 "wc=%d, adv=%d\n", 3088 (entry->etype & UVM_ET_SUBMAP) ? 'T' : 'F', 3089 (entry->etype & UVM_ET_COPYONWRITE) ? 'T' : 'F', 3090 (entry->etype & UVM_ET_NEEDSCOPY) ? 'T' : 'F', 3091 (entry->etype & UVM_ET_STACK) ? 'T' : 'F', 3092 entry->protection, entry->max_protection, 3093 entry->inheritance, entry->wired_count, entry->advice); 3094 3095 free = uvm_map_uaddr_e(map, entry); 3096 in_free = (free != NULL); 3097 (*pr)("\thole=%c, free=%c, guard=0x%lx, " 3098 "free=0x%lx-0x%lx\n", 3099 (entry->etype & UVM_ET_HOLE) ? 'T' : 'F', 3100 in_free ? 'T' : 'F', 3101 entry->guard, 3102 VMMAP_FREE_START(entry), VMMAP_FREE_END(entry)); 3103 (*pr)("\tfspace_augment=%lu\n", entry->fspace_augment); 3104 (*pr)("\tfreemapped=%c, uaddr=%p\n", 3105 (entry->etype & UVM_ET_FREEMAPPED) ? 'T' : 'F', free); 3106 if (free) { 3107 (*pr)("\t\t(0x%lx-0x%lx %s)\n", 3108 free->uaddr_minaddr, free->uaddr_maxaddr, 3109 free->uaddr_functions->uaddr_name); 3110 } 3111 } 3112 3113 print_uaddr: 3114 uvm_addr_print(map->uaddr_exe, "exe", full, pr); 3115 for (i = 0; i < nitems(map->uaddr_any); i++) { 3116 snprintf(&buf[0], sizeof(buf), "any[%d]", i); 3117 uvm_addr_print(map->uaddr_any[i], &buf[0], full, pr); 3118 } 3119 uvm_addr_print(map->uaddr_brk_stack, "brk/stack", full, pr); 3120 } 3121 3122 /* 3123 * uvm_object_printit: actually prints the object 3124 */ 3125 void 3126 uvm_object_printit(uobj, full, pr) 3127 struct uvm_object *uobj; 3128 boolean_t full; 3129 int (*pr)(const char *, ...); 3130 { 3131 struct vm_page *pg; 3132 int cnt = 0; 3133 3134 (*pr)("OBJECT %p: pgops=%p, npages=%d, ", 3135 uobj, uobj->pgops, uobj->uo_npages); 3136 if (UVM_OBJ_IS_KERN_OBJECT(uobj)) 3137 (*pr)("refs=<SYSTEM>\n"); 3138 else 3139 (*pr)("refs=%d\n", uobj->uo_refs); 3140 3141 if (!full) { 3142 return; 3143 } 3144 (*pr)(" PAGES <pg,offset>:\n "); 3145 RBT_FOREACH(pg, uvm_objtree, &uobj->memt) { 3146 (*pr)("<%p,0x%llx> ", pg, (long long)pg->offset); 3147 if ((cnt % 3) == 2) { 3148 (*pr)("\n "); 3149 } 3150 cnt++; 3151 } 3152 if ((cnt % 3) != 2) { 3153 (*pr)("\n"); 3154 } 3155 } 3156 3157 /* 3158 * uvm_page_printit: actually print the page 3159 */ 3160 static const char page_flagbits[] = 3161 "\20\1BUSY\2WANTED\3TABLED\4CLEAN\5CLEANCHK\6RELEASED\7FAKE\10RDONLY" 3162 "\11ZERO\12DEV\15PAGER1\21FREE\22INACTIVE\23ACTIVE\25ANON\26AOBJ" 3163 "\27ENCRYPT\31PMAP0\32PMAP1\33PMAP2\34PMAP3\35PMAP4\36PMAP5"; 3164 3165 void 3166 uvm_page_printit(pg, full, pr) 3167 struct vm_page *pg; 3168 boolean_t full; 3169 int (*pr)(const char *, ...); 3170 { 3171 struct vm_page *tpg; 3172 struct uvm_object *uobj; 3173 struct pglist *pgl; 3174 3175 (*pr)("PAGE %p:\n", pg); 3176 (*pr)(" flags=%b, vers=%d, wire_count=%d, pa=0x%llx\n", 3177 pg->pg_flags, page_flagbits, pg->pg_version, pg->wire_count, 3178 (long long)pg->phys_addr); 3179 (*pr)(" uobject=%p, uanon=%p, offset=0x%llx\n", 3180 pg->uobject, pg->uanon, (long long)pg->offset); 3181 #if defined(UVM_PAGE_TRKOWN) 3182 if (pg->pg_flags & PG_BUSY) 3183 (*pr)(" owning thread = %d, tag=%s", 3184 pg->owner, pg->owner_tag); 3185 else 3186 (*pr)(" page not busy, no owner"); 3187 #else 3188 (*pr)(" [page ownership tracking disabled]"); 3189 #endif 3190 (*pr)("\tvm_page_md %p\n", &pg->mdpage); 3191 3192 if (!full) 3193 return; 3194 3195 /* cross-verify object/anon */ 3196 if ((pg->pg_flags & PQ_FREE) == 0) { 3197 if (pg->pg_flags & PQ_ANON) { 3198 if (pg->uanon == NULL || pg->uanon->an_page != pg) 3199 (*pr)(" >>> ANON DOES NOT POINT HERE <<< (%p)\n", 3200 (pg->uanon) ? pg->uanon->an_page : NULL); 3201 else 3202 (*pr)(" anon backpointer is OK\n"); 3203 } else { 3204 uobj = pg->uobject; 3205 if (uobj) { 3206 (*pr)(" checking object list\n"); 3207 RBT_FOREACH(tpg, uvm_objtree, &uobj->memt) { 3208 if (tpg == pg) { 3209 break; 3210 } 3211 } 3212 if (tpg) 3213 (*pr)(" page found on object list\n"); 3214 else 3215 (*pr)(" >>> PAGE NOT FOUND " 3216 "ON OBJECT LIST! <<<\n"); 3217 } 3218 } 3219 } 3220 3221 /* cross-verify page queue */ 3222 if (pg->pg_flags & PQ_FREE) { 3223 if (uvm_pmr_isfree(pg)) 3224 (*pr)(" page found in uvm_pmemrange\n"); 3225 else 3226 (*pr)(" >>> page not found in uvm_pmemrange <<<\n"); 3227 pgl = NULL; 3228 } else if (pg->pg_flags & PQ_INACTIVE) { 3229 pgl = (pg->pg_flags & PQ_SWAPBACKED) ? 3230 &uvm.page_inactive_swp : &uvm.page_inactive_obj; 3231 } else if (pg->pg_flags & PQ_ACTIVE) { 3232 pgl = &uvm.page_active; 3233 } else { 3234 pgl = NULL; 3235 } 3236 3237 if (pgl) { 3238 (*pr)(" checking pageq list\n"); 3239 TAILQ_FOREACH(tpg, pgl, pageq) { 3240 if (tpg == pg) { 3241 break; 3242 } 3243 } 3244 if (tpg) 3245 (*pr)(" page found on pageq list\n"); 3246 else 3247 (*pr)(" >>> PAGE NOT FOUND ON PAGEQ LIST! <<<\n"); 3248 } 3249 } 3250 #endif 3251 3252 /* 3253 * uvm_map_protect: change map protection 3254 * 3255 * => set_max means set max_protection. 3256 * => map must be unlocked. 3257 */ 3258 int 3259 uvm_map_protect(struct vm_map *map, vaddr_t start, vaddr_t end, 3260 vm_prot_t new_prot, boolean_t set_max) 3261 { 3262 struct vm_map_entry *first, *iter; 3263 vm_prot_t old_prot; 3264 vm_prot_t mask; 3265 int error; 3266 3267 if (start > end) 3268 return EINVAL; 3269 start = MAX(start, map->min_offset); 3270 end = MIN(end, map->max_offset); 3271 if (start >= end) 3272 return 0; 3273 3274 error = 0; 3275 vm_map_lock(map); 3276 3277 /* 3278 * Set up first and last. 3279 * - first will contain first entry at or after start. 3280 */ 3281 first = uvm_map_entrybyaddr(&map->addr, start); 3282 KDASSERT(first != NULL); 3283 if (first->end <= start) 3284 first = RBT_NEXT(uvm_map_addr, first); 3285 3286 /* First, check for protection violations. */ 3287 for (iter = first; iter != NULL && iter->start < end; 3288 iter = RBT_NEXT(uvm_map_addr, iter)) { 3289 /* Treat memory holes as free space. */ 3290 if (iter->start == iter->end || UVM_ET_ISHOLE(iter)) 3291 continue; 3292 3293 if (UVM_ET_ISSUBMAP(iter)) { 3294 error = EINVAL; 3295 goto out; 3296 } 3297 if ((new_prot & iter->max_protection) != new_prot) { 3298 error = EACCES; 3299 goto out; 3300 } 3301 if (map == kernel_map && 3302 (new_prot & (PROT_WRITE | PROT_EXEC)) == (PROT_WRITE | PROT_EXEC)) 3303 panic("uvm_map_protect: kernel map W^X violation requested"); 3304 } 3305 3306 /* Fix protections. */ 3307 for (iter = first; iter != NULL && iter->start < end; 3308 iter = RBT_NEXT(uvm_map_addr, iter)) { 3309 /* Treat memory holes as free space. */ 3310 if (iter->start == iter->end || UVM_ET_ISHOLE(iter)) 3311 continue; 3312 3313 old_prot = iter->protection; 3314 3315 /* 3316 * Skip adapting protection iff old and new protection 3317 * are equal. 3318 */ 3319 if (set_max) { 3320 if (old_prot == (new_prot & old_prot) && 3321 iter->max_protection == new_prot) 3322 continue; 3323 } else { 3324 if (old_prot == new_prot) 3325 continue; 3326 } 3327 3328 UVM_MAP_CLIP_START(map, iter, start); 3329 UVM_MAP_CLIP_END(map, iter, end); 3330 3331 if (set_max) { 3332 iter->max_protection = new_prot; 3333 iter->protection &= new_prot; 3334 } else 3335 iter->protection = new_prot; 3336 3337 /* 3338 * update physical map if necessary. worry about copy-on-write 3339 * here -- CHECK THIS XXX 3340 */ 3341 if (iter->protection != old_prot) { 3342 mask = UVM_ET_ISCOPYONWRITE(iter) ? 3343 ~PROT_WRITE : PROT_MASK; 3344 3345 /* XXX should only wserial++ if no split occurs */ 3346 if (iter->protection & PROT_WRITE) 3347 map->wserial++; 3348 3349 /* update pmap */ 3350 if ((iter->protection & mask) == PROT_NONE && 3351 VM_MAPENT_ISWIRED(iter)) { 3352 /* 3353 * TODO(ariane) this is stupid. wired_count 3354 * is 0 if not wired, otherwise anything 3355 * larger than 0 (incremented once each time 3356 * wire is called). 3357 * Mostly to be able to undo the damage on 3358 * failure. Not the actually be a wired 3359 * refcounter... 3360 * Originally: iter->wired_count--; 3361 * (don't we have to unwire this in the pmap 3362 * as well?) 3363 */ 3364 iter->wired_count = 0; 3365 } 3366 pmap_protect(map->pmap, iter->start, iter->end, 3367 iter->protection & mask); 3368 } 3369 3370 /* 3371 * If the map is configured to lock any future mappings, 3372 * wire this entry now if the old protection was PROT_NONE 3373 * and the new protection is not PROT_NONE. 3374 */ 3375 if ((map->flags & VM_MAP_WIREFUTURE) != 0 && 3376 VM_MAPENT_ISWIRED(iter) == 0 && 3377 old_prot == PROT_NONE && 3378 new_prot != PROT_NONE) { 3379 if (uvm_map_pageable(map, iter->start, iter->end, 3380 FALSE, UVM_LK_ENTER | UVM_LK_EXIT) != 0) { 3381 /* 3382 * If locking the entry fails, remember the 3383 * error if it's the first one. Note we 3384 * still continue setting the protection in 3385 * the map, but it will return the resource 3386 * storage condition regardless. 3387 * 3388 * XXX Ignore what the actual error is, 3389 * XXX just call it a resource shortage 3390 * XXX so that it doesn't get confused 3391 * XXX what uvm_map_protect() itself would 3392 * XXX normally return. 3393 */ 3394 error = ENOMEM; 3395 } 3396 } 3397 } 3398 pmap_update(map->pmap); 3399 3400 out: 3401 vm_map_unlock(map); 3402 return error; 3403 } 3404 3405 /* 3406 * uvmspace_alloc: allocate a vmspace structure. 3407 * 3408 * - structure includes vm_map and pmap 3409 * - XXX: no locking on this structure 3410 * - refcnt set to 1, rest must be init'd by caller 3411 */ 3412 struct vmspace * 3413 uvmspace_alloc(vaddr_t min, vaddr_t max, boolean_t pageable, 3414 boolean_t remove_holes) 3415 { 3416 struct vmspace *vm; 3417 3418 vm = pool_get(&uvm_vmspace_pool, PR_WAITOK | PR_ZERO); 3419 uvmspace_init(vm, NULL, min, max, pageable, remove_holes); 3420 return (vm); 3421 } 3422 3423 /* 3424 * uvmspace_init: initialize a vmspace structure. 3425 * 3426 * - XXX: no locking on this structure 3427 * - refcnt set to 1, rest must be init'd by caller 3428 */ 3429 void 3430 uvmspace_init(struct vmspace *vm, struct pmap *pmap, vaddr_t min, vaddr_t max, 3431 boolean_t pageable, boolean_t remove_holes) 3432 { 3433 KASSERT(pmap == NULL || pmap == pmap_kernel()); 3434 3435 if (pmap) 3436 pmap_reference(pmap); 3437 else 3438 pmap = pmap_create(); 3439 vm->vm_map.pmap = pmap; 3440 3441 uvm_map_setup(&vm->vm_map, min, max, 3442 (pageable ? VM_MAP_PAGEABLE : 0) | VM_MAP_ISVMSPACE); 3443 3444 vm->vm_refcnt = 1; 3445 3446 if (remove_holes) 3447 pmap_remove_holes(vm); 3448 } 3449 3450 /* 3451 * uvmspace_share: share a vmspace between two processes 3452 * 3453 * - XXX: no locking on vmspace 3454 * - used for vfork 3455 */ 3456 3457 struct vmspace * 3458 uvmspace_share(struct process *pr) 3459 { 3460 struct vmspace *vm = pr->ps_vmspace; 3461 3462 vm->vm_refcnt++; 3463 return vm; 3464 } 3465 3466 /* 3467 * uvmspace_exec: the process wants to exec a new program 3468 * 3469 * - XXX: no locking on vmspace 3470 */ 3471 3472 void 3473 uvmspace_exec(struct proc *p, vaddr_t start, vaddr_t end) 3474 { 3475 struct process *pr = p->p_p; 3476 struct vmspace *nvm, *ovm = pr->ps_vmspace; 3477 struct vm_map *map = &ovm->vm_map; 3478 struct uvm_map_deadq dead_entries; 3479 3480 KASSERT((start & (vaddr_t)PAGE_MASK) == 0); 3481 KASSERT((end & (vaddr_t)PAGE_MASK) == 0 || 3482 (end & (vaddr_t)PAGE_MASK) == (vaddr_t)PAGE_MASK); 3483 3484 pmap_unuse_final(p); /* before stack addresses go away */ 3485 TAILQ_INIT(&dead_entries); 3486 3487 /* see if more than one process is using this vmspace... */ 3488 if (ovm->vm_refcnt == 1) { 3489 /* 3490 * If pr is the only process using its vmspace then 3491 * we can safely recycle that vmspace for the program 3492 * that is being exec'd. 3493 */ 3494 3495 #ifdef SYSVSHM 3496 /* 3497 * SYSV SHM semantics require us to kill all segments on an exec 3498 */ 3499 if (ovm->vm_shm) 3500 shmexit(ovm); 3501 #endif 3502 3503 /* 3504 * POSIX 1003.1b -- "lock future mappings" is revoked 3505 * when a process execs another program image. 3506 */ 3507 vm_map_lock(map); 3508 vm_map_modflags(map, 0, VM_MAP_WIREFUTURE); 3509 3510 /* 3511 * now unmap the old program 3512 * 3513 * Instead of attempting to keep the map valid, we simply 3514 * nuke all entries and ask uvm_map_setup to reinitialize 3515 * the map to the new boundaries. 3516 * 3517 * uvm_unmap_remove will actually nuke all entries for us 3518 * (as in, not replace them with free-memory entries). 3519 */ 3520 uvm_unmap_remove(map, map->min_offset, map->max_offset, 3521 &dead_entries, TRUE, FALSE); 3522 3523 KDASSERT(RBT_EMPTY(uvm_map_addr, &map->addr)); 3524 3525 /* Nuke statistics and boundaries. */ 3526 memset(&ovm->vm_startcopy, 0, 3527 (caddr_t) (ovm + 1) - (caddr_t) &ovm->vm_startcopy); 3528 3529 3530 if (end & (vaddr_t)PAGE_MASK) { 3531 end += 1; 3532 if (end == 0) /* overflow */ 3533 end -= PAGE_SIZE; 3534 } 3535 3536 /* Setup new boundaries and populate map with entries. */ 3537 map->min_offset = start; 3538 map->max_offset = end; 3539 uvm_map_setup_entries(map); 3540 vm_map_unlock(map); 3541 3542 /* but keep MMU holes unavailable */ 3543 pmap_remove_holes(ovm); 3544 } else { 3545 /* 3546 * pr's vmspace is being shared, so we can't reuse 3547 * it for pr since it is still being used for others. 3548 * allocate a new vmspace for pr 3549 */ 3550 nvm = uvmspace_alloc(start, end, 3551 (map->flags & VM_MAP_PAGEABLE) ? TRUE : FALSE, TRUE); 3552 3553 /* install new vmspace and drop our ref to the old one. */ 3554 pmap_deactivate(p); 3555 p->p_vmspace = pr->ps_vmspace = nvm; 3556 pmap_activate(p); 3557 3558 uvmspace_free(ovm); 3559 } 3560 3561 /* Release dead entries */ 3562 uvm_unmap_detach(&dead_entries, 0); 3563 } 3564 3565 /* 3566 * uvmspace_free: free a vmspace data structure 3567 * 3568 * - XXX: no locking on vmspace 3569 */ 3570 void 3571 uvmspace_free(struct vmspace *vm) 3572 { 3573 if (--vm->vm_refcnt == 0) { 3574 /* 3575 * lock the map, to wait out all other references to it. delete 3576 * all of the mappings and pages they hold, then call the pmap 3577 * module to reclaim anything left. 3578 */ 3579 #ifdef SYSVSHM 3580 /* Get rid of any SYSV shared memory segments. */ 3581 if (vm->vm_shm != NULL) 3582 shmexit(vm); 3583 #endif 3584 3585 uvm_map_teardown(&vm->vm_map); 3586 pool_put(&uvm_vmspace_pool, vm); 3587 } 3588 } 3589 3590 /* 3591 * uvm_share: Map the address range [srcaddr, srcaddr + sz) in 3592 * srcmap to the address range [dstaddr, dstaddr + sz) in 3593 * dstmap. 3594 * 3595 * The whole address range in srcmap must be backed by an object 3596 * (no holes). 3597 * 3598 * If successful, the address ranges share memory and the destination 3599 * address range uses the protection flags in prot. 3600 * 3601 * This routine assumes that sz is a multiple of PAGE_SIZE and 3602 * that dstaddr and srcaddr are page-aligned. 3603 */ 3604 int 3605 uvm_share(struct vm_map *dstmap, vaddr_t dstaddr, vm_prot_t prot, 3606 struct vm_map *srcmap, vaddr_t srcaddr, vsize_t sz) 3607 { 3608 int ret = 0; 3609 vaddr_t unmap_end; 3610 vaddr_t dstva; 3611 vsize_t off, len, n = sz; 3612 struct vm_map_entry *first = NULL, *last = NULL; 3613 struct vm_map_entry *src_entry, *psrc_entry = NULL; 3614 struct uvm_map_deadq dead; 3615 3616 if (srcaddr >= srcmap->max_offset || sz > srcmap->max_offset - srcaddr) 3617 return EINVAL; 3618 3619 TAILQ_INIT(&dead); 3620 vm_map_lock(dstmap); 3621 vm_map_lock_read(srcmap); 3622 3623 if (!uvm_map_isavail(dstmap, NULL, &first, &last, dstaddr, sz)) { 3624 ret = ENOMEM; 3625 goto exit_unlock; 3626 } 3627 if (!uvm_map_lookup_entry(srcmap, srcaddr, &src_entry)) { 3628 ret = EINVAL; 3629 goto exit_unlock; 3630 } 3631 3632 unmap_end = dstaddr; 3633 for (; src_entry != NULL; 3634 psrc_entry = src_entry, 3635 src_entry = RBT_NEXT(uvm_map_addr, src_entry)) { 3636 /* hole in address space, bail out */ 3637 if (psrc_entry != NULL && psrc_entry->end != src_entry->start) 3638 break; 3639 if (src_entry->start >= srcaddr + sz) 3640 break; 3641 3642 if (UVM_ET_ISSUBMAP(src_entry)) 3643 panic("uvm_share: encountered a submap (illegal)"); 3644 if (!UVM_ET_ISCOPYONWRITE(src_entry) && 3645 UVM_ET_ISNEEDSCOPY(src_entry)) 3646 panic("uvm_share: non-copy_on_write map entries " 3647 "marked needs_copy (illegal)"); 3648 3649 dstva = dstaddr; 3650 if (src_entry->start > srcaddr) { 3651 dstva += src_entry->start - srcaddr; 3652 off = 0; 3653 } else 3654 off = srcaddr - src_entry->start; 3655 3656 if (n < src_entry->end - src_entry->start) 3657 len = n; 3658 else 3659 len = src_entry->end - src_entry->start; 3660 n -= len; 3661 3662 if (uvm_mapent_share(dstmap, dstva, len, off, prot, prot, 3663 srcmap, src_entry, &dead) == NULL) 3664 break; 3665 3666 unmap_end = dstva + len; 3667 if (n == 0) 3668 goto exit_unlock; 3669 } 3670 3671 ret = EINVAL; 3672 uvm_unmap_remove(dstmap, dstaddr, unmap_end, &dead, FALSE, TRUE); 3673 3674 exit_unlock: 3675 vm_map_unlock_read(srcmap); 3676 vm_map_unlock(dstmap); 3677 uvm_unmap_detach(&dead, 0); 3678 3679 return ret; 3680 } 3681 3682 /* 3683 * Clone map entry into other map. 3684 * 3685 * Mapping will be placed at dstaddr, for the same length. 3686 * Space must be available. 3687 * Reference counters are incremented. 3688 */ 3689 struct vm_map_entry * 3690 uvm_mapent_clone(struct vm_map *dstmap, vaddr_t dstaddr, vsize_t dstlen, 3691 vsize_t off, vm_prot_t prot, vm_prot_t maxprot, 3692 struct vm_map_entry *old_entry, struct uvm_map_deadq *dead, 3693 int mapent_flags, int amap_share_flags) 3694 { 3695 struct vm_map_entry *new_entry, *first, *last; 3696 3697 KDASSERT(!UVM_ET_ISSUBMAP(old_entry)); 3698 3699 /* Create new entry (linked in on creation). Fill in first, last. */ 3700 first = last = NULL; 3701 if (!uvm_map_isavail(dstmap, NULL, &first, &last, dstaddr, dstlen)) { 3702 panic("uvmspace_fork: no space in map for " 3703 "entry in empty map"); 3704 } 3705 new_entry = uvm_map_mkentry(dstmap, first, last, 3706 dstaddr, dstlen, mapent_flags, dead, NULL); 3707 if (new_entry == NULL) 3708 return NULL; 3709 /* old_entry -> new_entry */ 3710 new_entry->object = old_entry->object; 3711 new_entry->offset = old_entry->offset; 3712 new_entry->aref = old_entry->aref; 3713 new_entry->etype |= old_entry->etype & ~UVM_ET_FREEMAPPED; 3714 new_entry->protection = prot; 3715 new_entry->max_protection = maxprot; 3716 new_entry->inheritance = old_entry->inheritance; 3717 new_entry->advice = old_entry->advice; 3718 3719 /* gain reference to object backing the map (can't be a submap). */ 3720 if (new_entry->aref.ar_amap) { 3721 new_entry->aref.ar_pageoff += off >> PAGE_SHIFT; 3722 amap_ref(new_entry->aref.ar_amap, new_entry->aref.ar_pageoff, 3723 (new_entry->end - new_entry->start) >> PAGE_SHIFT, 3724 amap_share_flags); 3725 } 3726 3727 if (UVM_ET_ISOBJ(new_entry) && 3728 new_entry->object.uvm_obj->pgops->pgo_reference) { 3729 new_entry->offset += off; 3730 new_entry->object.uvm_obj->pgops->pgo_reference 3731 (new_entry->object.uvm_obj); 3732 } 3733 3734 return new_entry; 3735 } 3736 3737 struct vm_map_entry * 3738 uvm_mapent_share(struct vm_map *dstmap, vaddr_t dstaddr, vsize_t dstlen, 3739 vsize_t off, vm_prot_t prot, vm_prot_t maxprot, struct vm_map *old_map, 3740 struct vm_map_entry *old_entry, struct uvm_map_deadq *dead) 3741 { 3742 /* 3743 * If old_entry refers to a copy-on-write region that has not yet been 3744 * written to (needs_copy flag is set), then we need to allocate a new 3745 * amap for old_entry. 3746 * 3747 * If we do not do this, and the process owning old_entry does a copy-on 3748 * write later, old_entry and new_entry will refer to different memory 3749 * regions, and the memory between the processes is no longer shared. 3750 * 3751 * [in other words, we need to clear needs_copy] 3752 */ 3753 3754 if (UVM_ET_ISNEEDSCOPY(old_entry)) { 3755 /* get our own amap, clears needs_copy */ 3756 amap_copy(old_map, old_entry, M_WAITOK, FALSE, 3757 0, 0); 3758 /* XXXCDC: WAITOK??? */ 3759 } 3760 3761 return uvm_mapent_clone(dstmap, dstaddr, dstlen, off, 3762 prot, maxprot, old_entry, dead, 0, AMAP_SHARED); 3763 } 3764 3765 /* 3766 * share the mapping: this means we want the old and 3767 * new entries to share amaps and backing objects. 3768 */ 3769 struct vm_map_entry * 3770 uvm_mapent_forkshared(struct vmspace *new_vm, struct vm_map *new_map, 3771 struct vm_map *old_map, 3772 struct vm_map_entry *old_entry, struct uvm_map_deadq *dead) 3773 { 3774 struct vm_map_entry *new_entry; 3775 3776 new_entry = uvm_mapent_share(new_map, old_entry->start, 3777 old_entry->end - old_entry->start, 0, old_entry->protection, 3778 old_entry->max_protection, old_map, old_entry, dead); 3779 3780 /* 3781 * pmap_copy the mappings: this routine is optional 3782 * but if it is there it will reduce the number of 3783 * page faults in the new proc. 3784 */ 3785 if (!UVM_ET_ISHOLE(new_entry)) 3786 pmap_copy(new_map->pmap, old_map->pmap, new_entry->start, 3787 (new_entry->end - new_entry->start), new_entry->start); 3788 3789 return (new_entry); 3790 } 3791 3792 /* 3793 * copy-on-write the mapping (using mmap's 3794 * MAP_PRIVATE semantics) 3795 * 3796 * allocate new_entry, adjust reference counts. 3797 * (note that new references are read-only). 3798 */ 3799 struct vm_map_entry * 3800 uvm_mapent_forkcopy(struct vmspace *new_vm, struct vm_map *new_map, 3801 struct vm_map *old_map, 3802 struct vm_map_entry *old_entry, struct uvm_map_deadq *dead) 3803 { 3804 struct vm_map_entry *new_entry; 3805 boolean_t protect_child; 3806 3807 new_entry = uvm_mapent_clone(new_map, old_entry->start, 3808 old_entry->end - old_entry->start, 0, old_entry->protection, 3809 old_entry->max_protection, old_entry, dead, 0, 0); 3810 3811 new_entry->etype |= 3812 (UVM_ET_COPYONWRITE|UVM_ET_NEEDSCOPY); 3813 3814 /* 3815 * the new entry will need an amap. it will either 3816 * need to be copied from the old entry or created 3817 * from scratch (if the old entry does not have an 3818 * amap). can we defer this process until later 3819 * (by setting "needs_copy") or do we need to copy 3820 * the amap now? 3821 * 3822 * we must copy the amap now if any of the following 3823 * conditions hold: 3824 * 1. the old entry has an amap and that amap is 3825 * being shared. this means that the old (parent) 3826 * process is sharing the amap with another 3827 * process. if we do not clear needs_copy here 3828 * we will end up in a situation where both the 3829 * parent and child process are referring to the 3830 * same amap with "needs_copy" set. if the 3831 * parent write-faults, the fault routine will 3832 * clear "needs_copy" in the parent by allocating 3833 * a new amap. this is wrong because the 3834 * parent is supposed to be sharing the old amap 3835 * and the new amap will break that. 3836 * 3837 * 2. if the old entry has an amap and a non-zero 3838 * wire count then we are going to have to call 3839 * amap_cow_now to avoid page faults in the 3840 * parent process. since amap_cow_now requires 3841 * "needs_copy" to be clear we might as well 3842 * clear it here as well. 3843 * 3844 */ 3845 if (old_entry->aref.ar_amap != NULL && 3846 ((amap_flags(old_entry->aref.ar_amap) & 3847 AMAP_SHARED) != 0 || 3848 VM_MAPENT_ISWIRED(old_entry))) { 3849 amap_copy(new_map, new_entry, M_WAITOK, FALSE, 3850 0, 0); 3851 /* XXXCDC: M_WAITOK ... ok? */ 3852 } 3853 3854 /* 3855 * if the parent's entry is wired down, then the 3856 * parent process does not want page faults on 3857 * access to that memory. this means that we 3858 * cannot do copy-on-write because we can't write 3859 * protect the old entry. in this case we 3860 * resolve all copy-on-write faults now, using 3861 * amap_cow_now. note that we have already 3862 * allocated any needed amap (above). 3863 */ 3864 if (VM_MAPENT_ISWIRED(old_entry)) { 3865 /* 3866 * resolve all copy-on-write faults now 3867 * (note that there is nothing to do if 3868 * the old mapping does not have an amap). 3869 * XXX: is it worthwhile to bother with 3870 * pmap_copy in this case? 3871 */ 3872 if (old_entry->aref.ar_amap) 3873 amap_cow_now(new_map, new_entry); 3874 } else { 3875 if (old_entry->aref.ar_amap) { 3876 /* 3877 * setup mappings to trigger copy-on-write faults 3878 * we must write-protect the parent if it has 3879 * an amap and it is not already "needs_copy"... 3880 * if it is already "needs_copy" then the parent 3881 * has already been write-protected by a previous 3882 * fork operation. 3883 * 3884 * if we do not write-protect the parent, then 3885 * we must be sure to write-protect the child 3886 * after the pmap_copy() operation. 3887 * 3888 * XXX: pmap_copy should have some way of telling 3889 * us that it didn't do anything so we can avoid 3890 * calling pmap_protect needlessly. 3891 */ 3892 if (!UVM_ET_ISNEEDSCOPY(old_entry)) { 3893 if (old_entry->max_protection & PROT_WRITE) { 3894 pmap_protect(old_map->pmap, 3895 old_entry->start, 3896 old_entry->end, 3897 old_entry->protection & 3898 ~PROT_WRITE); 3899 pmap_update(old_map->pmap); 3900 } 3901 old_entry->etype |= UVM_ET_NEEDSCOPY; 3902 } 3903 3904 /* parent must now be write-protected */ 3905 protect_child = FALSE; 3906 } else { 3907 /* 3908 * we only need to protect the child if the 3909 * parent has write access. 3910 */ 3911 if (old_entry->max_protection & PROT_WRITE) 3912 protect_child = TRUE; 3913 else 3914 protect_child = FALSE; 3915 } 3916 /* 3917 * copy the mappings 3918 * XXX: need a way to tell if this does anything 3919 */ 3920 if (!UVM_ET_ISHOLE(new_entry)) 3921 pmap_copy(new_map->pmap, old_map->pmap, 3922 new_entry->start, 3923 (old_entry->end - old_entry->start), 3924 old_entry->start); 3925 3926 /* protect the child's mappings if necessary */ 3927 if (protect_child) { 3928 pmap_protect(new_map->pmap, new_entry->start, 3929 new_entry->end, 3930 new_entry->protection & 3931 ~PROT_WRITE); 3932 } 3933 } 3934 3935 return (new_entry); 3936 } 3937 3938 /* 3939 * zero the mapping: the new entry will be zero initialized 3940 */ 3941 struct vm_map_entry * 3942 uvm_mapent_forkzero(struct vmspace *new_vm, struct vm_map *new_map, 3943 struct vm_map *old_map, 3944 struct vm_map_entry *old_entry, struct uvm_map_deadq *dead) 3945 { 3946 struct vm_map_entry *new_entry; 3947 3948 new_entry = uvm_mapent_clone(new_map, old_entry->start, 3949 old_entry->end - old_entry->start, 0, old_entry->protection, 3950 old_entry->max_protection, old_entry, dead, 0, 0); 3951 3952 new_entry->etype |= 3953 (UVM_ET_COPYONWRITE|UVM_ET_NEEDSCOPY); 3954 3955 if (new_entry->aref.ar_amap) { 3956 amap_unref(new_entry->aref.ar_amap, new_entry->aref.ar_pageoff, 3957 atop(new_entry->end - new_entry->start), 0); 3958 new_entry->aref.ar_amap = NULL; 3959 new_entry->aref.ar_pageoff = 0; 3960 } 3961 3962 if (UVM_ET_ISOBJ(new_entry)) { 3963 if (new_entry->object.uvm_obj->pgops->pgo_detach) 3964 new_entry->object.uvm_obj->pgops->pgo_detach( 3965 new_entry->object.uvm_obj); 3966 new_entry->object.uvm_obj = NULL; 3967 new_entry->etype &= ~UVM_ET_OBJ; 3968 } 3969 3970 return (new_entry); 3971 } 3972 3973 /* 3974 * uvmspace_fork: fork a process' main map 3975 * 3976 * => create a new vmspace for child process from parent. 3977 * => parent's map must not be locked. 3978 */ 3979 struct vmspace * 3980 uvmspace_fork(struct process *pr) 3981 { 3982 struct vmspace *vm1 = pr->ps_vmspace; 3983 struct vmspace *vm2; 3984 struct vm_map *old_map = &vm1->vm_map; 3985 struct vm_map *new_map; 3986 struct vm_map_entry *old_entry, *new_entry; 3987 struct uvm_map_deadq dead; 3988 3989 vm_map_lock(old_map); 3990 3991 vm2 = uvmspace_alloc(old_map->min_offset, old_map->max_offset, 3992 (old_map->flags & VM_MAP_PAGEABLE) ? TRUE : FALSE, FALSE); 3993 memcpy(&vm2->vm_startcopy, &vm1->vm_startcopy, 3994 (caddr_t) (vm1 + 1) - (caddr_t) &vm1->vm_startcopy); 3995 vm2->vm_dused = 0; /* Statistic managed by us. */ 3996 new_map = &vm2->vm_map; 3997 vm_map_lock(new_map); 3998 3999 /* go entry-by-entry */ 4000 TAILQ_INIT(&dead); 4001 RBT_FOREACH(old_entry, uvm_map_addr, &old_map->addr) { 4002 if (old_entry->start == old_entry->end) 4003 continue; 4004 4005 /* first, some sanity checks on the old entry */ 4006 if (UVM_ET_ISSUBMAP(old_entry)) { 4007 panic("fork: encountered a submap during fork " 4008 "(illegal)"); 4009 } 4010 4011 if (!UVM_ET_ISCOPYONWRITE(old_entry) && 4012 UVM_ET_ISNEEDSCOPY(old_entry)) { 4013 panic("fork: non-copy_on_write map entry marked " 4014 "needs_copy (illegal)"); 4015 } 4016 4017 /* Apply inheritance. */ 4018 switch (old_entry->inheritance) { 4019 case MAP_INHERIT_SHARE: 4020 new_entry = uvm_mapent_forkshared(vm2, new_map, 4021 old_map, old_entry, &dead); 4022 break; 4023 case MAP_INHERIT_COPY: 4024 new_entry = uvm_mapent_forkcopy(vm2, new_map, 4025 old_map, old_entry, &dead); 4026 break; 4027 case MAP_INHERIT_ZERO: 4028 new_entry = uvm_mapent_forkzero(vm2, new_map, 4029 old_map, old_entry, &dead); 4030 break; 4031 default: 4032 continue; 4033 } 4034 4035 /* Update process statistics. */ 4036 if (!UVM_ET_ISHOLE(new_entry)) 4037 new_map->size += new_entry->end - new_entry->start; 4038 if (!UVM_ET_ISOBJ(new_entry) && !UVM_ET_ISHOLE(new_entry)) { 4039 vm2->vm_dused += uvmspace_dused( 4040 new_map, new_entry->start, new_entry->end); 4041 } 4042 } 4043 4044 vm_map_unlock(old_map); 4045 vm_map_unlock(new_map); 4046 4047 /* 4048 * This can actually happen, if multiple entries described a 4049 * space in which an entry was inherited. 4050 */ 4051 uvm_unmap_detach(&dead, 0); 4052 4053 #ifdef SYSVSHM 4054 if (vm1->vm_shm) 4055 shmfork(vm1, vm2); 4056 #endif 4057 4058 return vm2; 4059 } 4060 4061 /* 4062 * uvm_map_hint: return the beginning of the best area suitable for 4063 * creating a new mapping with "prot" protection. 4064 */ 4065 vaddr_t 4066 uvm_map_hint(struct vmspace *vm, vm_prot_t prot, vaddr_t minaddr, 4067 vaddr_t maxaddr) 4068 { 4069 vaddr_t addr; 4070 vaddr_t spacing; 4071 4072 #ifdef __i386__ 4073 /* 4074 * If executable skip first two pages, otherwise start 4075 * after data + heap region. 4076 */ 4077 if ((prot & PROT_EXEC) != 0 && 4078 (vaddr_t)vm->vm_daddr >= I386_MAX_EXE_ADDR) { 4079 addr = (PAGE_SIZE*2) + 4080 (arc4random() & (I386_MAX_EXE_ADDR / 2 - 1)); 4081 return (round_page(addr)); 4082 } 4083 #endif 4084 4085 #if defined (__LP64__) 4086 spacing = MIN(4UL * 1024 * 1024 * 1024, MAXDSIZ) - 1; 4087 #else 4088 spacing = MIN(1 * 1024 * 1024 * 1024, MAXDSIZ) - 1; 4089 #endif 4090 4091 /* 4092 * Start malloc/mmap after the brk. 4093 */ 4094 addr = (vaddr_t)vm->vm_daddr + BRKSIZ; 4095 addr = MAX(addr, minaddr); 4096 4097 if (addr < maxaddr) { 4098 while (spacing > maxaddr - addr) 4099 spacing >>= 1; 4100 } 4101 addr += arc4random() & spacing; 4102 return (round_page(addr)); 4103 } 4104 4105 /* 4106 * uvm_map_submap: punch down part of a map into a submap 4107 * 4108 * => only the kernel_map is allowed to be submapped 4109 * => the purpose of submapping is to break up the locking granularity 4110 * of a larger map 4111 * => the range specified must have been mapped previously with a uvm_map() 4112 * call [with uobj==NULL] to create a blank map entry in the main map. 4113 * [And it had better still be blank!] 4114 * => maps which contain submaps should never be copied or forked. 4115 * => to remove a submap, use uvm_unmap() on the main map 4116 * and then uvm_map_deallocate() the submap. 4117 * => main map must be unlocked. 4118 * => submap must have been init'd and have a zero reference count. 4119 * [need not be locked as we don't actually reference it] 4120 */ 4121 int 4122 uvm_map_submap(struct vm_map *map, vaddr_t start, vaddr_t end, 4123 struct vm_map *submap) 4124 { 4125 struct vm_map_entry *entry; 4126 int result; 4127 4128 if (start > map->max_offset || end > map->max_offset || 4129 start < map->min_offset || end < map->min_offset) 4130 return EINVAL; 4131 4132 vm_map_lock(map); 4133 4134 if (uvm_map_lookup_entry(map, start, &entry)) { 4135 UVM_MAP_CLIP_START(map, entry, start); 4136 UVM_MAP_CLIP_END(map, entry, end); 4137 } else 4138 entry = NULL; 4139 4140 if (entry != NULL && 4141 entry->start == start && entry->end == end && 4142 entry->object.uvm_obj == NULL && entry->aref.ar_amap == NULL && 4143 !UVM_ET_ISCOPYONWRITE(entry) && !UVM_ET_ISNEEDSCOPY(entry)) { 4144 entry->etype |= UVM_ET_SUBMAP; 4145 entry->object.sub_map = submap; 4146 entry->offset = 0; 4147 uvm_map_reference(submap); 4148 result = 0; 4149 } else 4150 result = EINVAL; 4151 4152 vm_map_unlock(map); 4153 return(result); 4154 } 4155 4156 /* 4157 * uvm_map_checkprot: check protection in map 4158 * 4159 * => must allow specific protection in a fully allocated region. 4160 * => map mut be read or write locked by caller. 4161 */ 4162 boolean_t 4163 uvm_map_checkprot(struct vm_map *map, vaddr_t start, vaddr_t end, 4164 vm_prot_t protection) 4165 { 4166 struct vm_map_entry *entry; 4167 4168 if (start < map->min_offset || end > map->max_offset || start > end) 4169 return FALSE; 4170 if (start == end) 4171 return TRUE; 4172 4173 /* 4174 * Iterate entries. 4175 */ 4176 for (entry = uvm_map_entrybyaddr(&map->addr, start); 4177 entry != NULL && entry->start < end; 4178 entry = RBT_NEXT(uvm_map_addr, entry)) { 4179 /* Fail if a hole is found. */ 4180 if (UVM_ET_ISHOLE(entry) || 4181 (entry->end < end && entry->end != VMMAP_FREE_END(entry))) 4182 return FALSE; 4183 4184 /* Check protection. */ 4185 if ((entry->protection & protection) != protection) 4186 return FALSE; 4187 } 4188 return TRUE; 4189 } 4190 4191 /* 4192 * uvm_map_create: create map 4193 */ 4194 vm_map_t 4195 uvm_map_create(pmap_t pmap, vaddr_t min, vaddr_t max, int flags) 4196 { 4197 vm_map_t map; 4198 4199 map = malloc(sizeof *map, M_VMMAP, M_WAITOK); 4200 map->pmap = pmap; 4201 uvm_map_setup(map, min, max, flags); 4202 return (map); 4203 } 4204 4205 /* 4206 * uvm_map_deallocate: drop reference to a map 4207 * 4208 * => caller must not lock map 4209 * => we will zap map if ref count goes to zero 4210 */ 4211 void 4212 uvm_map_deallocate(vm_map_t map) 4213 { 4214 int c; 4215 struct uvm_map_deadq dead; 4216 4217 c = --map->ref_count; 4218 if (c > 0) { 4219 return; 4220 } 4221 4222 /* 4223 * all references gone. unmap and free. 4224 * 4225 * No lock required: we are only one to access this map. 4226 */ 4227 TAILQ_INIT(&dead); 4228 uvm_tree_sanity(map, __FILE__, __LINE__); 4229 uvm_unmap_remove(map, map->min_offset, map->max_offset, &dead, 4230 TRUE, FALSE); 4231 pmap_destroy(map->pmap); 4232 KASSERT(RBT_EMPTY(uvm_map_addr, &map->addr)); 4233 free(map, M_VMMAP, sizeof *map); 4234 4235 uvm_unmap_detach(&dead, 0); 4236 } 4237 4238 /* 4239 * uvm_map_inherit: set inheritance code for range of addrs in map. 4240 * 4241 * => map must be unlocked 4242 * => note that the inherit code is used during a "fork". see fork 4243 * code for details. 4244 */ 4245 int 4246 uvm_map_inherit(struct vm_map *map, vaddr_t start, vaddr_t end, 4247 vm_inherit_t new_inheritance) 4248 { 4249 struct vm_map_entry *entry; 4250 4251 switch (new_inheritance) { 4252 case MAP_INHERIT_NONE: 4253 case MAP_INHERIT_COPY: 4254 case MAP_INHERIT_SHARE: 4255 case MAP_INHERIT_ZERO: 4256 break; 4257 default: 4258 return (EINVAL); 4259 } 4260 4261 if (start > end) 4262 return EINVAL; 4263 start = MAX(start, map->min_offset); 4264 end = MIN(end, map->max_offset); 4265 if (start >= end) 4266 return 0; 4267 4268 vm_map_lock(map); 4269 4270 entry = uvm_map_entrybyaddr(&map->addr, start); 4271 if (entry->end > start) 4272 UVM_MAP_CLIP_START(map, entry, start); 4273 else 4274 entry = RBT_NEXT(uvm_map_addr, entry); 4275 4276 while (entry != NULL && entry->start < end) { 4277 UVM_MAP_CLIP_END(map, entry, end); 4278 entry->inheritance = new_inheritance; 4279 entry = RBT_NEXT(uvm_map_addr, entry); 4280 } 4281 4282 vm_map_unlock(map); 4283 return (0); 4284 } 4285 4286 /* 4287 * uvm_map_advice: set advice code for range of addrs in map. 4288 * 4289 * => map must be unlocked 4290 */ 4291 int 4292 uvm_map_advice(struct vm_map *map, vaddr_t start, vaddr_t end, int new_advice) 4293 { 4294 struct vm_map_entry *entry; 4295 4296 switch (new_advice) { 4297 case MADV_NORMAL: 4298 case MADV_RANDOM: 4299 case MADV_SEQUENTIAL: 4300 break; 4301 default: 4302 return (EINVAL); 4303 } 4304 4305 if (start > end) 4306 return EINVAL; 4307 start = MAX(start, map->min_offset); 4308 end = MIN(end, map->max_offset); 4309 if (start >= end) 4310 return 0; 4311 4312 vm_map_lock(map); 4313 4314 entry = uvm_map_entrybyaddr(&map->addr, start); 4315 if (entry != NULL && entry->end > start) 4316 UVM_MAP_CLIP_START(map, entry, start); 4317 else if (entry!= NULL) 4318 entry = RBT_NEXT(uvm_map_addr, entry); 4319 4320 /* 4321 * XXXJRT: disallow holes? 4322 */ 4323 while (entry != NULL && entry->start < end) { 4324 UVM_MAP_CLIP_END(map, entry, end); 4325 entry->advice = new_advice; 4326 entry = RBT_NEXT(uvm_map_addr, entry); 4327 } 4328 4329 vm_map_unlock(map); 4330 return (0); 4331 } 4332 4333 /* 4334 * uvm_map_extract: extract a mapping from a map and put it somewhere 4335 * in the kernel_map, setting protection to max_prot. 4336 * 4337 * => map should be unlocked (we will write lock it and kernel_map) 4338 * => returns 0 on success, error code otherwise 4339 * => start must be page aligned 4340 * => len must be page sized 4341 * => flags: 4342 * UVM_EXTRACT_FIXPROT: set prot to maxprot as we go 4343 * Mappings are QREF's. 4344 */ 4345 int 4346 uvm_map_extract(struct vm_map *srcmap, vaddr_t start, vsize_t len, 4347 vaddr_t *dstaddrp, int flags) 4348 { 4349 struct uvm_map_deadq dead; 4350 struct vm_map_entry *first, *entry, *newentry, *tmp1, *tmp2; 4351 vaddr_t dstaddr; 4352 vaddr_t end; 4353 vaddr_t cp_start; 4354 vsize_t cp_len, cp_off; 4355 int error; 4356 4357 TAILQ_INIT(&dead); 4358 end = start + len; 4359 4360 /* 4361 * Sanity check on the parameters. 4362 * Also, since the mapping may not contain gaps, error out if the 4363 * mapped area is not in source map. 4364 */ 4365 if ((start & (vaddr_t)PAGE_MASK) != 0 || 4366 (end & (vaddr_t)PAGE_MASK) != 0 || end < start) 4367 return EINVAL; 4368 if (start < srcmap->min_offset || end > srcmap->max_offset) 4369 return EINVAL; 4370 4371 /* Initialize dead entries. Handle len == 0 case. */ 4372 if (len == 0) 4373 return 0; 4374 4375 /* Acquire lock on srcmap. */ 4376 vm_map_lock(srcmap); 4377 4378 /* Lock srcmap, lookup first and last entry in <start,len>. */ 4379 first = uvm_map_entrybyaddr(&srcmap->addr, start); 4380 4381 /* Check that the range is contiguous. */ 4382 for (entry = first; entry != NULL && entry->end < end; 4383 entry = RBT_NEXT(uvm_map_addr, entry)) { 4384 if (VMMAP_FREE_END(entry) != entry->end || 4385 UVM_ET_ISHOLE(entry)) { 4386 error = EINVAL; 4387 goto fail; 4388 } 4389 } 4390 if (entry == NULL || UVM_ET_ISHOLE(entry)) { 4391 error = EINVAL; 4392 goto fail; 4393 } 4394 4395 /* 4396 * Handle need-copy flag. 4397 */ 4398 for (entry = first; entry != NULL && entry->start < end; 4399 entry = RBT_NEXT(uvm_map_addr, entry)) { 4400 if (UVM_ET_ISNEEDSCOPY(entry)) 4401 amap_copy(srcmap, entry, M_NOWAIT, 4402 UVM_ET_ISSTACK(entry) ? FALSE : TRUE, start, end); 4403 if (UVM_ET_ISNEEDSCOPY(entry)) { 4404 /* 4405 * amap_copy failure 4406 */ 4407 error = ENOMEM; 4408 goto fail; 4409 } 4410 } 4411 4412 /* Lock destination map (kernel_map). */ 4413 vm_map_lock(kernel_map); 4414 4415 if (uvm_map_findspace(kernel_map, &tmp1, &tmp2, &dstaddr, len, 4416 MAX(PAGE_SIZE, PMAP_PREFER_ALIGN()), PMAP_PREFER_OFFSET(start), 4417 PROT_NONE, 0) != 0) { 4418 error = ENOMEM; 4419 goto fail2; 4420 } 4421 *dstaddrp = dstaddr; 4422 4423 /* 4424 * We now have srcmap and kernel_map locked. 4425 * dstaddr contains the destination offset in dstmap. 4426 */ 4427 /* step 1: start looping through map entries, performing extraction. */ 4428 for (entry = first; entry != NULL && entry->start < end; 4429 entry = RBT_NEXT(uvm_map_addr, entry)) { 4430 KDASSERT(!UVM_ET_ISNEEDSCOPY(entry)); 4431 if (UVM_ET_ISHOLE(entry)) 4432 continue; 4433 4434 /* Calculate uvm_mapent_clone parameters. */ 4435 cp_start = entry->start; 4436 if (cp_start < start) { 4437 cp_off = start - cp_start; 4438 cp_start = start; 4439 } else 4440 cp_off = 0; 4441 cp_len = MIN(entry->end, end) - cp_start; 4442 4443 newentry = uvm_mapent_clone(kernel_map, 4444 cp_start - start + dstaddr, cp_len, cp_off, 4445 entry->protection, entry->max_protection, 4446 entry, &dead, flags, AMAP_SHARED | AMAP_REFALL); 4447 if (newentry == NULL) { 4448 error = ENOMEM; 4449 goto fail2_unmap; 4450 } 4451 kernel_map->size += cp_len; 4452 if (flags & UVM_EXTRACT_FIXPROT) 4453 newentry->protection = newentry->max_protection; 4454 4455 /* 4456 * Step 2: perform pmap copy. 4457 * (Doing this in the loop saves one RB traversal.) 4458 */ 4459 pmap_copy(kernel_map->pmap, srcmap->pmap, 4460 cp_start - start + dstaddr, cp_len, cp_start); 4461 } 4462 pmap_update(kernel_map->pmap); 4463 4464 error = 0; 4465 4466 /* Unmap copied entries on failure. */ 4467 fail2_unmap: 4468 if (error) { 4469 uvm_unmap_remove(kernel_map, dstaddr, dstaddr + len, &dead, 4470 FALSE, TRUE); 4471 } 4472 4473 /* Release maps, release dead entries. */ 4474 fail2: 4475 vm_map_unlock(kernel_map); 4476 4477 fail: 4478 vm_map_unlock(srcmap); 4479 4480 uvm_unmap_detach(&dead, 0); 4481 4482 return error; 4483 } 4484 4485 /* 4486 * uvm_map_clean: clean out a map range 4487 * 4488 * => valid flags: 4489 * if (flags & PGO_CLEANIT): dirty pages are cleaned first 4490 * if (flags & PGO_SYNCIO): dirty pages are written synchronously 4491 * if (flags & PGO_DEACTIVATE): any cached pages are deactivated after clean 4492 * if (flags & PGO_FREE): any cached pages are freed after clean 4493 * => returns an error if any part of the specified range isn't mapped 4494 * => never a need to flush amap layer since the anonymous memory has 4495 * no permanent home, but may deactivate pages there 4496 * => called from sys_msync() and sys_madvise() 4497 * => caller must not write-lock map (read OK). 4498 * => we may sleep while cleaning if SYNCIO [with map read-locked] 4499 */ 4500 4501 int 4502 uvm_map_clean(struct vm_map *map, vaddr_t start, vaddr_t end, int flags) 4503 { 4504 struct vm_map_entry *first, *entry; 4505 struct vm_amap *amap; 4506 struct vm_anon *anon; 4507 struct vm_page *pg; 4508 struct uvm_object *uobj; 4509 vaddr_t cp_start, cp_end; 4510 int refs; 4511 int error; 4512 boolean_t rv; 4513 4514 KASSERT((flags & (PGO_FREE|PGO_DEACTIVATE)) != 4515 (PGO_FREE|PGO_DEACTIVATE)); 4516 4517 if (start > end || start < map->min_offset || end > map->max_offset) 4518 return EINVAL; 4519 4520 vm_map_lock_read(map); 4521 first = uvm_map_entrybyaddr(&map->addr, start); 4522 4523 /* Make a first pass to check for holes. */ 4524 for (entry = first; entry != NULL && entry->start < end; 4525 entry = RBT_NEXT(uvm_map_addr, entry)) { 4526 if (UVM_ET_ISSUBMAP(entry)) { 4527 vm_map_unlock_read(map); 4528 return EINVAL; 4529 } 4530 if (UVM_ET_ISSUBMAP(entry) || 4531 UVM_ET_ISHOLE(entry) || 4532 (entry->end < end && 4533 VMMAP_FREE_END(entry) != entry->end)) { 4534 vm_map_unlock_read(map); 4535 return EFAULT; 4536 } 4537 } 4538 4539 error = 0; 4540 for (entry = first; entry != NULL && entry->start < end; 4541 entry = RBT_NEXT(uvm_map_addr, entry)) { 4542 amap = entry->aref.ar_amap; /* top layer */ 4543 if (UVM_ET_ISOBJ(entry)) 4544 uobj = entry->object.uvm_obj; 4545 else 4546 uobj = NULL; 4547 4548 /* 4549 * No amap cleaning necessary if: 4550 * - there's no amap 4551 * - we're not deactivating or freeing pages. 4552 */ 4553 if (amap == NULL || (flags & (PGO_DEACTIVATE|PGO_FREE)) == 0) 4554 goto flush_object; 4555 4556 cp_start = MAX(entry->start, start); 4557 cp_end = MIN(entry->end, end); 4558 4559 for (; cp_start != cp_end; cp_start += PAGE_SIZE) { 4560 anon = amap_lookup(&entry->aref, 4561 cp_start - entry->start); 4562 if (anon == NULL) 4563 continue; 4564 4565 pg = anon->an_page; 4566 if (pg == NULL) { 4567 continue; 4568 } 4569 KASSERT(pg->pg_flags & PQ_ANON); 4570 4571 switch (flags & (PGO_CLEANIT|PGO_FREE|PGO_DEACTIVATE)) { 4572 /* 4573 * XXX In these first 3 cases, we always just 4574 * XXX deactivate the page. We may want to 4575 * XXX handle the different cases more 4576 * XXX specifically, in the future. 4577 */ 4578 case PGO_CLEANIT|PGO_FREE: 4579 case PGO_CLEANIT|PGO_DEACTIVATE: 4580 case PGO_DEACTIVATE: 4581 deactivate_it: 4582 /* skip the page if it's wired */ 4583 if (pg->wire_count != 0) 4584 break; 4585 4586 uvm_lock_pageq(); 4587 4588 KASSERT(pg->uanon == anon); 4589 4590 /* zap all mappings for the page. */ 4591 pmap_page_protect(pg, PROT_NONE); 4592 4593 /* ...and deactivate the page. */ 4594 uvm_pagedeactivate(pg); 4595 4596 uvm_unlock_pageq(); 4597 break; 4598 case PGO_FREE: 4599 /* 4600 * If there are multiple references to 4601 * the amap, just deactivate the page. 4602 */ 4603 if (amap_refs(amap) > 1) 4604 goto deactivate_it; 4605 4606 /* XXX skip the page if it's wired */ 4607 if (pg->wire_count != 0) { 4608 break; 4609 } 4610 amap_unadd(&entry->aref, 4611 cp_start - entry->start); 4612 refs = --anon->an_ref; 4613 if (refs == 0) 4614 uvm_anfree(anon); 4615 break; 4616 default: 4617 panic("uvm_map_clean: weird flags"); 4618 } 4619 } 4620 4621 flush_object: 4622 cp_start = MAX(entry->start, start); 4623 cp_end = MIN(entry->end, end); 4624 4625 /* 4626 * flush pages if we've got a valid backing object. 4627 * 4628 * Don't PGO_FREE if we don't have write permission 4629 * and don't flush if this is a copy-on-write object 4630 * since we can't know our permissions on it. 4631 */ 4632 if (uobj != NULL && 4633 ((flags & PGO_FREE) == 0 || 4634 ((entry->max_protection & PROT_WRITE) != 0 && 4635 (entry->etype & UVM_ET_COPYONWRITE) == 0))) { 4636 rv = uobj->pgops->pgo_flush(uobj, 4637 cp_start - entry->start + entry->offset, 4638 cp_end - entry->start + entry->offset, flags); 4639 4640 if (rv == FALSE) 4641 error = EFAULT; 4642 } 4643 } 4644 4645 vm_map_unlock_read(map); 4646 return error; 4647 } 4648 4649 /* 4650 * UVM_MAP_CLIP_END implementation 4651 */ 4652 void 4653 uvm_map_clip_end(struct vm_map *map, struct vm_map_entry *entry, vaddr_t addr) 4654 { 4655 struct vm_map_entry *tmp; 4656 4657 KASSERT(entry->start < addr && VMMAP_FREE_END(entry) > addr); 4658 tmp = uvm_mapent_alloc(map, 0); 4659 4660 /* Invoke splitentry. */ 4661 uvm_map_splitentry(map, entry, tmp, addr); 4662 } 4663 4664 /* 4665 * UVM_MAP_CLIP_START implementation 4666 * 4667 * Clippers are required to not change the pointers to the entry they are 4668 * clipping on. 4669 * Since uvm_map_splitentry turns the original entry into the lowest 4670 * entry (address wise) we do a swap between the new entry and the original 4671 * entry, prior to calling uvm_map_splitentry. 4672 */ 4673 void 4674 uvm_map_clip_start(struct vm_map *map, struct vm_map_entry *entry, vaddr_t addr) 4675 { 4676 struct vm_map_entry *tmp; 4677 struct uvm_addr_state *free; 4678 4679 /* Unlink original. */ 4680 free = uvm_map_uaddr_e(map, entry); 4681 uvm_mapent_free_remove(map, free, entry); 4682 uvm_mapent_addr_remove(map, entry); 4683 4684 /* Copy entry. */ 4685 KASSERT(entry->start < addr && VMMAP_FREE_END(entry) > addr); 4686 tmp = uvm_mapent_alloc(map, 0); 4687 uvm_mapent_copy(entry, tmp); 4688 4689 /* Put new entry in place of original entry. */ 4690 uvm_mapent_addr_insert(map, tmp); 4691 uvm_mapent_free_insert(map, free, tmp); 4692 4693 /* Invoke splitentry. */ 4694 uvm_map_splitentry(map, tmp, entry, addr); 4695 } 4696 4697 /* 4698 * Boundary fixer. 4699 */ 4700 static __inline vaddr_t uvm_map_boundfix(vaddr_t, vaddr_t, vaddr_t); 4701 static __inline vaddr_t 4702 uvm_map_boundfix(vaddr_t min, vaddr_t max, vaddr_t bound) 4703 { 4704 return (min < bound && max > bound) ? bound : max; 4705 } 4706 4707 /* 4708 * Choose free list based on address at start of free space. 4709 * 4710 * The uvm_addr_state returned contains addr and is the first of: 4711 * - uaddr_exe 4712 * - uaddr_brk_stack 4713 * - uaddr_any 4714 */ 4715 struct uvm_addr_state* 4716 uvm_map_uaddr(struct vm_map *map, vaddr_t addr) 4717 { 4718 struct uvm_addr_state *uaddr; 4719 int i; 4720 4721 /* Special case the first page, to prevent mmap from returning 0. */ 4722 if (addr < VMMAP_MIN_ADDR) 4723 return NULL; 4724 4725 /* Upper bound for kernel maps at uvm_maxkaddr. */ 4726 if ((map->flags & VM_MAP_ISVMSPACE) == 0) { 4727 if (addr >= uvm_maxkaddr) 4728 return NULL; 4729 } 4730 4731 /* Is the address inside the exe-only map? */ 4732 if (map->uaddr_exe != NULL && addr >= map->uaddr_exe->uaddr_minaddr && 4733 addr < map->uaddr_exe->uaddr_maxaddr) 4734 return map->uaddr_exe; 4735 4736 /* Check if the space falls inside brk/stack area. */ 4737 if ((addr >= map->b_start && addr < map->b_end) || 4738 (addr >= map->s_start && addr < map->s_end)) { 4739 if (map->uaddr_brk_stack != NULL && 4740 addr >= map->uaddr_brk_stack->uaddr_minaddr && 4741 addr < map->uaddr_brk_stack->uaddr_maxaddr) { 4742 return map->uaddr_brk_stack; 4743 } else 4744 return NULL; 4745 } 4746 4747 /* 4748 * Check the other selectors. 4749 * 4750 * These selectors are only marked as the owner, if they have insert 4751 * functions. 4752 */ 4753 for (i = 0; i < nitems(map->uaddr_any); i++) { 4754 uaddr = map->uaddr_any[i]; 4755 if (uaddr == NULL) 4756 continue; 4757 if (uaddr->uaddr_functions->uaddr_free_insert == NULL) 4758 continue; 4759 4760 if (addr >= uaddr->uaddr_minaddr && 4761 addr < uaddr->uaddr_maxaddr) 4762 return uaddr; 4763 } 4764 4765 return NULL; 4766 } 4767 4768 /* 4769 * Choose free list based on address at start of free space. 4770 * 4771 * The uvm_addr_state returned contains addr and is the first of: 4772 * - uaddr_exe 4773 * - uaddr_brk_stack 4774 * - uaddr_any 4775 */ 4776 struct uvm_addr_state* 4777 uvm_map_uaddr_e(struct vm_map *map, struct vm_map_entry *entry) 4778 { 4779 return uvm_map_uaddr(map, VMMAP_FREE_START(entry)); 4780 } 4781 4782 /* 4783 * Returns the first free-memory boundary that is crossed by [min-max]. 4784 */ 4785 vsize_t 4786 uvm_map_boundary(struct vm_map *map, vaddr_t min, vaddr_t max) 4787 { 4788 struct uvm_addr_state *uaddr; 4789 int i; 4790 4791 /* Never return first page. */ 4792 max = uvm_map_boundfix(min, max, VMMAP_MIN_ADDR); 4793 4794 /* Treat the maxkaddr special, if the map is a kernel_map. */ 4795 if ((map->flags & VM_MAP_ISVMSPACE) == 0) 4796 max = uvm_map_boundfix(min, max, uvm_maxkaddr); 4797 4798 /* Check for exe-only boundaries. */ 4799 if (map->uaddr_exe != NULL) { 4800 max = uvm_map_boundfix(min, max, map->uaddr_exe->uaddr_minaddr); 4801 max = uvm_map_boundfix(min, max, map->uaddr_exe->uaddr_maxaddr); 4802 } 4803 4804 /* Check for exe-only boundaries. */ 4805 if (map->uaddr_brk_stack != NULL) { 4806 max = uvm_map_boundfix(min, max, 4807 map->uaddr_brk_stack->uaddr_minaddr); 4808 max = uvm_map_boundfix(min, max, 4809 map->uaddr_brk_stack->uaddr_maxaddr); 4810 } 4811 4812 /* Check other boundaries. */ 4813 for (i = 0; i < nitems(map->uaddr_any); i++) { 4814 uaddr = map->uaddr_any[i]; 4815 if (uaddr != NULL) { 4816 max = uvm_map_boundfix(min, max, uaddr->uaddr_minaddr); 4817 max = uvm_map_boundfix(min, max, uaddr->uaddr_maxaddr); 4818 } 4819 } 4820 4821 /* Boundaries at stack and brk() area. */ 4822 max = uvm_map_boundfix(min, max, map->s_start); 4823 max = uvm_map_boundfix(min, max, map->s_end); 4824 max = uvm_map_boundfix(min, max, map->b_start); 4825 max = uvm_map_boundfix(min, max, map->b_end); 4826 4827 return max; 4828 } 4829 4830 /* 4831 * Update map allocation start and end addresses from proc vmspace. 4832 */ 4833 void 4834 uvm_map_vmspace_update(struct vm_map *map, 4835 struct uvm_map_deadq *dead, int flags) 4836 { 4837 struct vmspace *vm; 4838 vaddr_t b_start, b_end, s_start, s_end; 4839 4840 KASSERT(map->flags & VM_MAP_ISVMSPACE); 4841 KASSERT(offsetof(struct vmspace, vm_map) == 0); 4842 4843 /* 4844 * Derive actual allocation boundaries from vmspace. 4845 */ 4846 vm = (struct vmspace *)map; 4847 b_start = (vaddr_t)vm->vm_daddr; 4848 b_end = b_start + BRKSIZ; 4849 s_start = MIN((vaddr_t)vm->vm_maxsaddr, (vaddr_t)vm->vm_minsaddr); 4850 s_end = MAX((vaddr_t)vm->vm_maxsaddr, (vaddr_t)vm->vm_minsaddr); 4851 #ifdef DIAGNOSTIC 4852 if ((b_start & (vaddr_t)PAGE_MASK) != 0 || 4853 (b_end & (vaddr_t)PAGE_MASK) != 0 || 4854 (s_start & (vaddr_t)PAGE_MASK) != 0 || 4855 (s_end & (vaddr_t)PAGE_MASK) != 0) { 4856 panic("uvm_map_vmspace_update: vmspace %p invalid bounds: " 4857 "b=0x%lx-0x%lx s=0x%lx-0x%lx", 4858 vm, b_start, b_end, s_start, s_end); 4859 } 4860 #endif 4861 4862 if (__predict_true(map->b_start == b_start && map->b_end == b_end && 4863 map->s_start == s_start && map->s_end == s_end)) 4864 return; 4865 4866 uvm_map_freelist_update(map, dead, b_start, b_end, 4867 s_start, s_end, flags); 4868 } 4869 4870 /* 4871 * Grow kernel memory. 4872 * 4873 * This function is only called for kernel maps when an allocation fails. 4874 * 4875 * If the map has a gap that is large enough to accommodate alloc_sz, this 4876 * function will make sure map->free will include it. 4877 */ 4878 void 4879 uvm_map_kmem_grow(struct vm_map *map, struct uvm_map_deadq *dead, 4880 vsize_t alloc_sz, int flags) 4881 { 4882 vsize_t sz; 4883 vaddr_t end; 4884 struct vm_map_entry *entry; 4885 4886 /* Kernel memory only. */ 4887 KASSERT((map->flags & VM_MAP_ISVMSPACE) == 0); 4888 /* Destroy free list. */ 4889 uvm_map_freelist_update_clear(map, dead); 4890 4891 /* Include the guard page in the hard minimum requirement of alloc_sz. */ 4892 if (map->flags & VM_MAP_GUARDPAGES) 4893 alloc_sz += PAGE_SIZE; 4894 4895 /* 4896 * Grow by ALLOCMUL * alloc_sz, but at least VM_MAP_KSIZE_DELTA. 4897 * 4898 * Don't handle the case where the multiplication overflows: 4899 * if that happens, the allocation is probably too big anyway. 4900 */ 4901 sz = MAX(VM_MAP_KSIZE_ALLOCMUL * alloc_sz, VM_MAP_KSIZE_DELTA); 4902 4903 /* 4904 * Walk forward until a gap large enough for alloc_sz shows up. 4905 * 4906 * We assume the kernel map has no boundaries. 4907 * uvm_maxkaddr may be zero. 4908 */ 4909 end = MAX(uvm_maxkaddr, map->min_offset); 4910 entry = uvm_map_entrybyaddr(&map->addr, end); 4911 while (entry && entry->fspace < alloc_sz) 4912 entry = RBT_NEXT(uvm_map_addr, entry); 4913 if (entry) { 4914 end = MAX(VMMAP_FREE_START(entry), end); 4915 end += MIN(sz, map->max_offset - end); 4916 } else 4917 end = map->max_offset; 4918 4919 /* Reserve pmap entries. */ 4920 #ifdef PMAP_GROWKERNEL 4921 uvm_maxkaddr = pmap_growkernel(end); 4922 #else 4923 uvm_maxkaddr = MAX(uvm_maxkaddr, end); 4924 #endif 4925 4926 /* Rebuild free list. */ 4927 uvm_map_freelist_update_refill(map, flags); 4928 } 4929 4930 /* 4931 * Freelist update subfunction: unlink all entries from freelists. 4932 */ 4933 void 4934 uvm_map_freelist_update_clear(struct vm_map *map, struct uvm_map_deadq *dead) 4935 { 4936 struct uvm_addr_state *free; 4937 struct vm_map_entry *entry, *prev, *next; 4938 4939 prev = NULL; 4940 for (entry = RBT_MIN(uvm_map_addr, &map->addr); entry != NULL; 4941 entry = next) { 4942 next = RBT_NEXT(uvm_map_addr, entry); 4943 4944 free = uvm_map_uaddr_e(map, entry); 4945 uvm_mapent_free_remove(map, free, entry); 4946 4947 if (prev != NULL && entry->start == entry->end) { 4948 prev->fspace += VMMAP_FREE_END(entry) - entry->end; 4949 uvm_mapent_addr_remove(map, entry); 4950 DEAD_ENTRY_PUSH(dead, entry); 4951 } else 4952 prev = entry; 4953 } 4954 } 4955 4956 /* 4957 * Freelist update subfunction: refill the freelists with entries. 4958 */ 4959 void 4960 uvm_map_freelist_update_refill(struct vm_map *map, int flags) 4961 { 4962 struct vm_map_entry *entry; 4963 vaddr_t min, max; 4964 4965 RBT_FOREACH(entry, uvm_map_addr, &map->addr) { 4966 min = VMMAP_FREE_START(entry); 4967 max = VMMAP_FREE_END(entry); 4968 entry->fspace = 0; 4969 4970 entry = uvm_map_fix_space(map, entry, min, max, flags); 4971 } 4972 4973 uvm_tree_sanity(map, __FILE__, __LINE__); 4974 } 4975 4976 /* 4977 * Change {a,b}_{start,end} allocation ranges and associated free lists. 4978 */ 4979 void 4980 uvm_map_freelist_update(struct vm_map *map, struct uvm_map_deadq *dead, 4981 vaddr_t b_start, vaddr_t b_end, vaddr_t s_start, vaddr_t s_end, int flags) 4982 { 4983 KDASSERT(b_end >= b_start && s_end >= s_start); 4984 4985 /* Clear all free lists. */ 4986 uvm_map_freelist_update_clear(map, dead); 4987 4988 /* Apply new bounds. */ 4989 map->b_start = b_start; 4990 map->b_end = b_end; 4991 map->s_start = s_start; 4992 map->s_end = s_end; 4993 4994 /* Refill free lists. */ 4995 uvm_map_freelist_update_refill(map, flags); 4996 } 4997 4998 /* 4999 * Assign a uvm_addr_state to the specified pointer in vm_map. 5000 * 5001 * May sleep. 5002 */ 5003 void 5004 uvm_map_set_uaddr(struct vm_map *map, struct uvm_addr_state **which, 5005 struct uvm_addr_state *newval) 5006 { 5007 struct uvm_map_deadq dead; 5008 5009 /* Pointer which must be in this map. */ 5010 KASSERT(which != NULL); 5011 KASSERT((void*)map <= (void*)(which) && 5012 (void*)(which) < (void*)(map + 1)); 5013 5014 vm_map_lock(map); 5015 TAILQ_INIT(&dead); 5016 uvm_map_freelist_update_clear(map, &dead); 5017 5018 uvm_addr_destroy(*which); 5019 *which = newval; 5020 5021 uvm_map_freelist_update_refill(map, 0); 5022 vm_map_unlock(map); 5023 uvm_unmap_detach(&dead, 0); 5024 } 5025 5026 /* 5027 * Correct space insert. 5028 * 5029 * Entry must not be on any freelist. 5030 */ 5031 struct vm_map_entry* 5032 uvm_map_fix_space(struct vm_map *map, struct vm_map_entry *entry, 5033 vaddr_t min, vaddr_t max, int flags) 5034 { 5035 struct uvm_addr_state *free, *entfree; 5036 vaddr_t lmax; 5037 5038 KASSERT(entry == NULL || (entry->etype & UVM_ET_FREEMAPPED) == 0); 5039 KDASSERT(min <= max); 5040 KDASSERT((entry != NULL && VMMAP_FREE_END(entry) == min) || 5041 min == map->min_offset); 5042 5043 /* 5044 * During the function, entfree will always point at the uaddr state 5045 * for entry. 5046 */ 5047 entfree = (entry == NULL ? NULL : 5048 uvm_map_uaddr_e(map, entry)); 5049 5050 while (min != max) { 5051 /* Claim guard page for entry. */ 5052 if ((map->flags & VM_MAP_GUARDPAGES) && entry != NULL && 5053 VMMAP_FREE_END(entry) == entry->end && 5054 entry->start != entry->end) { 5055 if (max - min == 2 * PAGE_SIZE) { 5056 /* 5057 * If the free-space gap is exactly 2 pages, 5058 * we make the guard 2 pages instead of 1. 5059 * Because in a guarded map, an area needs 5060 * at least 2 pages to allocate from: 5061 * one page for the allocation and one for 5062 * the guard. 5063 */ 5064 entry->guard = 2 * PAGE_SIZE; 5065 min = max; 5066 } else { 5067 entry->guard = PAGE_SIZE; 5068 min += PAGE_SIZE; 5069 } 5070 continue; 5071 } 5072 5073 /* 5074 * Handle the case where entry has a 2-page guard, but the 5075 * space after entry is freed. 5076 */ 5077 if (entry != NULL && entry->fspace == 0 && 5078 entry->guard > PAGE_SIZE) { 5079 entry->guard = PAGE_SIZE; 5080 min = VMMAP_FREE_START(entry); 5081 } 5082 5083 lmax = uvm_map_boundary(map, min, max); 5084 free = uvm_map_uaddr(map, min); 5085 5086 /* 5087 * Entries are merged if they point at the same uvm_free(). 5088 * Exception to that rule: if min == uvm_maxkaddr, a new 5089 * entry is started regardless (otherwise the allocators 5090 * will get confused). 5091 */ 5092 if (entry != NULL && free == entfree && 5093 !((map->flags & VM_MAP_ISVMSPACE) == 0 && 5094 min == uvm_maxkaddr)) { 5095 KDASSERT(VMMAP_FREE_END(entry) == min); 5096 entry->fspace += lmax - min; 5097 } else { 5098 /* 5099 * Commit entry to free list: it'll not be added to 5100 * anymore. 5101 * We'll start a new entry and add to that entry 5102 * instead. 5103 */ 5104 if (entry != NULL) 5105 uvm_mapent_free_insert(map, entfree, entry); 5106 5107 /* New entry for new uaddr. */ 5108 entry = uvm_mapent_alloc(map, flags); 5109 KDASSERT(entry != NULL); 5110 entry->end = entry->start = min; 5111 entry->guard = 0; 5112 entry->fspace = lmax - min; 5113 entry->object.uvm_obj = NULL; 5114 entry->offset = 0; 5115 entry->etype = 0; 5116 entry->protection = entry->max_protection = 0; 5117 entry->inheritance = 0; 5118 entry->wired_count = 0; 5119 entry->advice = 0; 5120 entry->aref.ar_pageoff = 0; 5121 entry->aref.ar_amap = NULL; 5122 uvm_mapent_addr_insert(map, entry); 5123 5124 entfree = free; 5125 } 5126 5127 min = lmax; 5128 } 5129 /* Finally put entry on the uaddr state. */ 5130 if (entry != NULL) 5131 uvm_mapent_free_insert(map, entfree, entry); 5132 5133 return entry; 5134 } 5135 5136 /* 5137 * MQuery style of allocation. 5138 * 5139 * This allocator searches forward until sufficient space is found to map 5140 * the given size. 5141 * 5142 * XXX: factor in offset (via pmap_prefer) and protection? 5143 */ 5144 int 5145 uvm_map_mquery(struct vm_map *map, vaddr_t *addr_p, vsize_t sz, voff_t offset, 5146 int flags) 5147 { 5148 struct vm_map_entry *entry, *last; 5149 vaddr_t addr; 5150 vaddr_t tmp, pmap_align, pmap_offset; 5151 int error; 5152 5153 addr = *addr_p; 5154 vm_map_lock_read(map); 5155 5156 /* Configure pmap prefer. */ 5157 if (offset != UVM_UNKNOWN_OFFSET) { 5158 pmap_align = MAX(PAGE_SIZE, PMAP_PREFER_ALIGN()); 5159 pmap_offset = PMAP_PREFER_OFFSET(offset); 5160 } else { 5161 pmap_align = PAGE_SIZE; 5162 pmap_offset = 0; 5163 } 5164 5165 /* Align address to pmap_prefer unless FLAG_FIXED is set. */ 5166 if (!(flags & UVM_FLAG_FIXED) && offset != UVM_UNKNOWN_OFFSET) { 5167 tmp = (addr & ~(pmap_align - 1)) | pmap_offset; 5168 if (tmp < addr) 5169 tmp += pmap_align; 5170 addr = tmp; 5171 } 5172 5173 /* First, check if the requested range is fully available. */ 5174 entry = uvm_map_entrybyaddr(&map->addr, addr); 5175 last = NULL; 5176 if (uvm_map_isavail(map, NULL, &entry, &last, addr, sz)) { 5177 error = 0; 5178 goto out; 5179 } 5180 if (flags & UVM_FLAG_FIXED) { 5181 error = EINVAL; 5182 goto out; 5183 } 5184 5185 error = ENOMEM; /* Default error from here. */ 5186 5187 /* 5188 * At this point, the memory at <addr, sz> is not available. 5189 * The reasons are: 5190 * [1] it's outside the map, 5191 * [2] it starts in used memory (and therefore needs to move 5192 * toward the first free page in entry), 5193 * [3] it starts in free memory but bumps into used memory. 5194 * 5195 * Note that for case [2], the forward moving is handled by the 5196 * for loop below. 5197 */ 5198 if (entry == NULL) { 5199 /* [1] Outside the map. */ 5200 if (addr >= map->max_offset) 5201 goto out; 5202 else 5203 entry = RBT_MIN(uvm_map_addr, &map->addr); 5204 } else if (VMMAP_FREE_START(entry) <= addr) { 5205 /* [3] Bumped into used memory. */ 5206 entry = RBT_NEXT(uvm_map_addr, entry); 5207 } 5208 5209 /* Test if the next entry is sufficient for the allocation. */ 5210 for (; entry != NULL; 5211 entry = RBT_NEXT(uvm_map_addr, entry)) { 5212 if (entry->fspace == 0) 5213 continue; 5214 addr = VMMAP_FREE_START(entry); 5215 5216 restart: /* Restart address checks on address change. */ 5217 tmp = (addr & ~(pmap_align - 1)) | pmap_offset; 5218 if (tmp < addr) 5219 tmp += pmap_align; 5220 addr = tmp; 5221 if (addr >= VMMAP_FREE_END(entry)) 5222 continue; 5223 5224 /* Skip brk() allocation addresses. */ 5225 if (addr + sz > map->b_start && addr < map->b_end) { 5226 if (VMMAP_FREE_END(entry) > map->b_end) { 5227 addr = map->b_end; 5228 goto restart; 5229 } else 5230 continue; 5231 } 5232 /* Skip stack allocation addresses. */ 5233 if (addr + sz > map->s_start && addr < map->s_end) { 5234 if (VMMAP_FREE_END(entry) > map->s_end) { 5235 addr = map->s_end; 5236 goto restart; 5237 } else 5238 continue; 5239 } 5240 5241 last = NULL; 5242 if (uvm_map_isavail(map, NULL, &entry, &last, addr, sz)) { 5243 error = 0; 5244 goto out; 5245 } 5246 } 5247 5248 out: 5249 vm_map_unlock_read(map); 5250 if (error == 0) 5251 *addr_p = addr; 5252 return error; 5253 } 5254 5255 /* 5256 * Determine allocation bias. 5257 * 5258 * Returns 1 if we should bias to high addresses, -1 for a bias towards low 5259 * addresses, or 0 for no bias. 5260 * The bias mechanism is intended to avoid clashing with brk() and stack 5261 * areas. 5262 */ 5263 int 5264 uvm_mapent_bias(struct vm_map *map, struct vm_map_entry *entry) 5265 { 5266 vaddr_t start, end; 5267 5268 start = VMMAP_FREE_START(entry); 5269 end = VMMAP_FREE_END(entry); 5270 5271 /* Stay at the top of brk() area. */ 5272 if (end >= map->b_start && start < map->b_end) 5273 return 1; 5274 /* Stay at the far end of the stack area. */ 5275 if (end >= map->s_start && start < map->s_end) { 5276 #ifdef MACHINE_STACK_GROWS_UP 5277 return 1; 5278 #else 5279 return -1; 5280 #endif 5281 } 5282 5283 /* No bias, this area is meant for us. */ 5284 return 0; 5285 } 5286 5287 5288 boolean_t 5289 vm_map_lock_try_ln(struct vm_map *map, char *file, int line) 5290 { 5291 boolean_t rv; 5292 5293 if (map->flags & VM_MAP_INTRSAFE) { 5294 rv = mtx_enter_try(&map->mtx); 5295 } else { 5296 mtx_enter(&map->flags_lock); 5297 if (map->flags & VM_MAP_BUSY) { 5298 mtx_leave(&map->flags_lock); 5299 return (FALSE); 5300 } 5301 mtx_leave(&map->flags_lock); 5302 rv = (rw_enter(&map->lock, RW_WRITE|RW_NOSLEEP) == 0); 5303 /* check if the lock is busy and back out if we won the race */ 5304 if (rv) { 5305 mtx_enter(&map->flags_lock); 5306 if (map->flags & VM_MAP_BUSY) { 5307 rw_exit(&map->lock); 5308 rv = FALSE; 5309 } 5310 mtx_leave(&map->flags_lock); 5311 } 5312 } 5313 5314 if (rv) { 5315 map->timestamp++; 5316 LPRINTF(("map lock: %p (at %s %d)\n", map, file, line)); 5317 uvm_tree_sanity(map, file, line); 5318 uvm_tree_size_chk(map, file, line); 5319 } 5320 5321 return (rv); 5322 } 5323 5324 void 5325 vm_map_lock_ln(struct vm_map *map, char *file, int line) 5326 { 5327 if ((map->flags & VM_MAP_INTRSAFE) == 0) { 5328 do { 5329 mtx_enter(&map->flags_lock); 5330 tryagain: 5331 while (map->flags & VM_MAP_BUSY) { 5332 map->flags |= VM_MAP_WANTLOCK; 5333 msleep(&map->flags, &map->flags_lock, 5334 PVM, vmmapbsy, 0); 5335 } 5336 mtx_leave(&map->flags_lock); 5337 } while (rw_enter(&map->lock, RW_WRITE|RW_SLEEPFAIL) != 0); 5338 /* check if the lock is busy and back out if we won the race */ 5339 mtx_enter(&map->flags_lock); 5340 if (map->flags & VM_MAP_BUSY) { 5341 rw_exit(&map->lock); 5342 goto tryagain; 5343 } 5344 mtx_leave(&map->flags_lock); 5345 } else { 5346 mtx_enter(&map->mtx); 5347 } 5348 5349 map->timestamp++; 5350 LPRINTF(("map lock: %p (at %s %d)\n", map, file, line)); 5351 uvm_tree_sanity(map, file, line); 5352 uvm_tree_size_chk(map, file, line); 5353 } 5354 5355 void 5356 vm_map_lock_read_ln(struct vm_map *map, char *file, int line) 5357 { 5358 if ((map->flags & VM_MAP_INTRSAFE) == 0) 5359 rw_enter_read(&map->lock); 5360 else 5361 mtx_enter(&map->mtx); 5362 LPRINTF(("map lock: %p (at %s %d)\n", map, file, line)); 5363 uvm_tree_sanity(map, file, line); 5364 uvm_tree_size_chk(map, file, line); 5365 } 5366 5367 void 5368 vm_map_unlock_ln(struct vm_map *map, char *file, int line) 5369 { 5370 uvm_tree_sanity(map, file, line); 5371 uvm_tree_size_chk(map, file, line); 5372 LPRINTF(("map unlock: %p (at %s %d)\n", map, file, line)); 5373 if ((map->flags & VM_MAP_INTRSAFE) == 0) 5374 rw_exit(&map->lock); 5375 else 5376 mtx_leave(&map->mtx); 5377 } 5378 5379 void 5380 vm_map_unlock_read_ln(struct vm_map *map, char *file, int line) 5381 { 5382 /* XXX: RO */ uvm_tree_sanity(map, file, line); 5383 /* XXX: RO */ uvm_tree_size_chk(map, file, line); 5384 LPRINTF(("map unlock: %p (at %s %d)\n", map, file, line)); 5385 if ((map->flags & VM_MAP_INTRSAFE) == 0) 5386 rw_exit_read(&map->lock); 5387 else 5388 mtx_leave(&map->mtx); 5389 } 5390 5391 void 5392 vm_map_downgrade_ln(struct vm_map *map, char *file, int line) 5393 { 5394 uvm_tree_sanity(map, file, line); 5395 uvm_tree_size_chk(map, file, line); 5396 LPRINTF(("map unlock: %p (at %s %d)\n", map, file, line)); 5397 LPRINTF(("map lock: %p (at %s %d)\n", map, file, line)); 5398 KASSERT((map->flags & VM_MAP_INTRSAFE) == 0); 5399 if ((map->flags & VM_MAP_INTRSAFE) == 0) 5400 rw_enter(&map->lock, RW_DOWNGRADE); 5401 } 5402 5403 void 5404 vm_map_upgrade_ln(struct vm_map *map, char *file, int line) 5405 { 5406 /* XXX: RO */ uvm_tree_sanity(map, file, line); 5407 /* XXX: RO */ uvm_tree_size_chk(map, file, line); 5408 LPRINTF(("map unlock: %p (at %s %d)\n", map, file, line)); 5409 KASSERT((map->flags & VM_MAP_INTRSAFE) == 0); 5410 if ((map->flags & VM_MAP_INTRSAFE) == 0) { 5411 rw_exit_read(&map->lock); 5412 rw_enter_write(&map->lock); 5413 } 5414 LPRINTF(("map lock: %p (at %s %d)\n", map, file, line)); 5415 uvm_tree_sanity(map, file, line); 5416 } 5417 5418 void 5419 vm_map_busy_ln(struct vm_map *map, char *file, int line) 5420 { 5421 KASSERT((map->flags & VM_MAP_INTRSAFE) == 0); 5422 mtx_enter(&map->flags_lock); 5423 map->flags |= VM_MAP_BUSY; 5424 mtx_leave(&map->flags_lock); 5425 } 5426 5427 void 5428 vm_map_unbusy_ln(struct vm_map *map, char *file, int line) 5429 { 5430 int oflags; 5431 5432 KASSERT((map->flags & VM_MAP_INTRSAFE) == 0); 5433 mtx_enter(&map->flags_lock); 5434 oflags = map->flags; 5435 map->flags &= ~(VM_MAP_BUSY|VM_MAP_WANTLOCK); 5436 mtx_leave(&map->flags_lock); 5437 if (oflags & VM_MAP_WANTLOCK) 5438 wakeup(&map->flags); 5439 } 5440 5441 #ifndef SMALL_KERNEL 5442 int 5443 uvm_map_fill_vmmap(struct vm_map *map, struct kinfo_vmentry *kve, 5444 size_t *lenp) 5445 { 5446 struct vm_map_entry *entry; 5447 vaddr_t start; 5448 int cnt, maxcnt, error = 0; 5449 5450 KASSERT(*lenp > 0); 5451 KASSERT((*lenp % sizeof(*kve)) == 0); 5452 cnt = 0; 5453 maxcnt = *lenp / sizeof(*kve); 5454 KASSERT(maxcnt > 0); 5455 5456 /* 5457 * Return only entries whose address is above the given base 5458 * address. This allows userland to iterate without knowing the 5459 * number of entries beforehand. 5460 */ 5461 start = (vaddr_t)kve[0].kve_start; 5462 5463 vm_map_lock(map); 5464 RBT_FOREACH(entry, uvm_map_addr, &map->addr) { 5465 if (cnt == maxcnt) { 5466 error = ENOMEM; 5467 break; 5468 } 5469 if (start != 0 && entry->start < start) 5470 continue; 5471 kve->kve_start = entry->start; 5472 kve->kve_end = entry->end; 5473 kve->kve_guard = entry->guard; 5474 kve->kve_fspace = entry->fspace; 5475 kve->kve_fspace_augment = entry->fspace_augment; 5476 kve->kve_offset = entry->offset; 5477 kve->kve_wired_count = entry->wired_count; 5478 kve->kve_etype = entry->etype; 5479 kve->kve_protection = entry->protection; 5480 kve->kve_max_protection = entry->max_protection; 5481 kve->kve_advice = entry->advice; 5482 kve->kve_inheritance = entry->inheritance; 5483 kve->kve_flags = entry->flags; 5484 kve++; 5485 cnt++; 5486 } 5487 vm_map_unlock(map); 5488 5489 KASSERT(cnt <= maxcnt); 5490 5491 *lenp = sizeof(*kve) * cnt; 5492 return error; 5493 } 5494 #endif 5495 5496 5497 RBT_GENERATE_AUGMENT(uvm_map_addr, vm_map_entry, daddrs.addr_entry, 5498 uvm_mapentry_addrcmp, uvm_map_addr_augment); 5499 5500 5501 /* 5502 * MD code: vmspace allocator setup. 5503 */ 5504 5505 #ifdef __i386__ 5506 void 5507 uvm_map_setup_md(struct vm_map *map) 5508 { 5509 vaddr_t min, max; 5510 5511 min = map->min_offset; 5512 max = map->max_offset; 5513 5514 /* 5515 * Ensure the selectors will not try to manage page 0; 5516 * it's too special. 5517 */ 5518 if (min < VMMAP_MIN_ADDR) 5519 min = VMMAP_MIN_ADDR; 5520 5521 #if 0 /* Cool stuff, not yet */ 5522 /* Executable code is special. */ 5523 map->uaddr_exe = uaddr_rnd_create(min, I386_MAX_EXE_ADDR); 5524 /* Place normal allocations beyond executable mappings. */ 5525 map->uaddr_any[3] = uaddr_pivot_create(2 * I386_MAX_EXE_ADDR, max); 5526 #else /* Crappy stuff, for now */ 5527 map->uaddr_any[0] = uaddr_rnd_create(min, max); 5528 #endif 5529 5530 #ifndef SMALL_KERNEL 5531 map->uaddr_brk_stack = uaddr_stack_brk_create(min, max); 5532 #endif /* !SMALL_KERNEL */ 5533 } 5534 #elif __LP64__ 5535 void 5536 uvm_map_setup_md(struct vm_map *map) 5537 { 5538 vaddr_t min, max; 5539 5540 min = map->min_offset; 5541 max = map->max_offset; 5542 5543 /* 5544 * Ensure the selectors will not try to manage page 0; 5545 * it's too special. 5546 */ 5547 if (min < VMMAP_MIN_ADDR) 5548 min = VMMAP_MIN_ADDR; 5549 5550 #if 0 /* Cool stuff, not yet */ 5551 map->uaddr_any[3] = uaddr_pivot_create(MAX(min, 0x100000000ULL), max); 5552 #else /* Crappy stuff, for now */ 5553 map->uaddr_any[0] = uaddr_rnd_create(min, max); 5554 #endif 5555 5556 #ifndef SMALL_KERNEL 5557 map->uaddr_brk_stack = uaddr_stack_brk_create(min, max); 5558 #endif /* !SMALL_KERNEL */ 5559 } 5560 #else /* non-i386, 32 bit */ 5561 void 5562 uvm_map_setup_md(struct vm_map *map) 5563 { 5564 vaddr_t min, max; 5565 5566 min = map->min_offset; 5567 max = map->max_offset; 5568 5569 /* 5570 * Ensure the selectors will not try to manage page 0; 5571 * it's too special. 5572 */ 5573 if (min < VMMAP_MIN_ADDR) 5574 min = VMMAP_MIN_ADDR; 5575 5576 #if 0 /* Cool stuff, not yet */ 5577 map->uaddr_any[3] = uaddr_pivot_create(min, max); 5578 #else /* Crappy stuff, for now */ 5579 map->uaddr_any[0] = uaddr_rnd_create(min, max); 5580 #endif 5581 5582 #ifndef SMALL_KERNEL 5583 map->uaddr_brk_stack = uaddr_stack_brk_create(min, max); 5584 #endif /* !SMALL_KERNEL */ 5585 } 5586 #endif 5587