Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/vm/vm_mmap.c
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1 /*- 2 * Copyright (c) 1988 University of Utah. 3 * Copyright (c) 1991, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * the Systems Programming Group of the University of Utah Computer 8 * Science Department. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$ 35 * 36 * @(#)vm_mmap.c 8.4 (Berkeley) 1/12/94 37 */ 38 39 /* 40 * Mapped file (mmap) interface to VM 41 */ 42 43 #include <sys/cdefs.h> 44 __FBSDID("$FreeBSD: releng/11.1/sys/vm/vm_mmap.c 320763 2017-07-07 06:29:18Z kib $"); 45 46 #include "opt_compat.h" 47 #include "opt_hwpmc_hooks.h" 48 #include "opt_vm.h" 49 50 #include <sys/param.h> 51 #include <sys/systm.h> 52 #include <sys/capsicum.h> 53 #include <sys/kernel.h> 54 #include <sys/lock.h> 55 #include <sys/mutex.h> 56 #include <sys/sysproto.h> 57 #include <sys/filedesc.h> 58 #include <sys/priv.h> 59 #include <sys/proc.h> 60 #include <sys/procctl.h> 61 #include <sys/racct.h> 62 #include <sys/resource.h> 63 #include <sys/resourcevar.h> 64 #include <sys/rwlock.h> 65 #include <sys/sysctl.h> 66 #include <sys/vnode.h> 67 #include <sys/fcntl.h> 68 #include <sys/file.h> 69 #include <sys/mman.h> 70 #include <sys/mount.h> 71 #include <sys/conf.h> 72 #include <sys/stat.h> 73 #include <sys/syscallsubr.h> 74 #include <sys/sysent.h> 75 #include <sys/vmmeter.h> 76 77 #include <security/audit/audit.h> 78 #include <security/mac/mac_framework.h> 79 80 #include <vm/vm.h> 81 #include <vm/vm_param.h> 82 #include <vm/pmap.h> 83 #include <vm/vm_map.h> 84 #include <vm/vm_object.h> 85 #include <vm/vm_page.h> 86 #include <vm/vm_pager.h> 87 #include <vm/vm_pageout.h> 88 #include <vm/vm_extern.h> 89 #include <vm/vm_page.h> 90 #include <vm/vnode_pager.h> 91 92 #ifdef HWPMC_HOOKS 93 #include <sys/pmckern.h> 94 #endif 95 96 int old_mlock = 0; 97 SYSCTL_INT(_vm, OID_AUTO, old_mlock, CTLFLAG_RWTUN, &old_mlock, 0, 98 "Do not apply RLIMIT_MEMLOCK on mlockall"); 99 100 #ifdef MAP_32BIT 101 #define MAP_32BIT_MAX_ADDR ((vm_offset_t)1 << 31) 102 #endif 103 104 #ifndef _SYS_SYSPROTO_H_ 105 struct sbrk_args { 106 int incr; 107 }; 108 #endif 109 110 int 111 sys_sbrk(struct thread *td, struct sbrk_args *uap) 112 { 113 /* Not yet implemented */ 114 return (EOPNOTSUPP); 115 } 116 117 #ifndef _SYS_SYSPROTO_H_ 118 struct sstk_args { 119 int incr; 120 }; 121 #endif 122 123 int 124 sys_sstk(struct thread *td, struct sstk_args *uap) 125 { 126 /* Not yet implemented */ 127 return (EOPNOTSUPP); 128 } 129 130 #if defined(COMPAT_43) 131 #ifndef _SYS_SYSPROTO_H_ 132 struct getpagesize_args { 133 int dummy; 134 }; 135 #endif 136 137 int 138 ogetpagesize(struct thread *td, struct getpagesize_args *uap) 139 { 140 141 td->td_retval[0] = PAGE_SIZE; 142 return (0); 143 } 144 #endif /* COMPAT_43 */ 145 146 147 /* 148 * Memory Map (mmap) system call. Note that the file offset 149 * and address are allowed to be NOT page aligned, though if 150 * the MAP_FIXED flag it set, both must have the same remainder 151 * modulo the PAGE_SIZE (POSIX 1003.1b). If the address is not 152 * page-aligned, the actual mapping starts at trunc_page(addr) 153 * and the return value is adjusted up by the page offset. 154 * 155 * Generally speaking, only character devices which are themselves 156 * memory-based, such as a video framebuffer, can be mmap'd. Otherwise 157 * there would be no cache coherency between a descriptor and a VM mapping 158 * both to the same character device. 159 */ 160 #ifndef _SYS_SYSPROTO_H_ 161 struct mmap_args { 162 void *addr; 163 size_t len; 164 int prot; 165 int flags; 166 int fd; 167 long pad; 168 off_t pos; 169 }; 170 #endif 171 172 int 173 sys_mmap(struct thread *td, struct mmap_args *uap) 174 { 175 176 return (kern_mmap(td, (uintptr_t)uap->addr, uap->len, uap->prot, 177 uap->flags, uap->fd, uap->pos)); 178 } 179 180 int 181 kern_mmap(struct thread *td, uintptr_t addr0, size_t size, int prot, int flags, 182 int fd, off_t pos) 183 { 184 struct vmspace *vms; 185 struct file *fp; 186 vm_offset_t addr; 187 vm_size_t pageoff; 188 vm_prot_t cap_maxprot; 189 int align, error; 190 cap_rights_t rights; 191 192 vms = td->td_proc->p_vmspace; 193 fp = NULL; 194 AUDIT_ARG_FD(fd); 195 addr = addr0; 196 197 /* 198 * Ignore old flags that used to be defined but did not do anything. 199 */ 200 flags &= ~(MAP_RESERVED0020 | MAP_RESERVED0040); 201 202 /* 203 * Enforce the constraints. 204 * Mapping of length 0 is only allowed for old binaries. 205 * Anonymous mapping shall specify -1 as filedescriptor and 206 * zero position for new code. Be nice to ancient a.out 207 * binaries and correct pos for anonymous mapping, since old 208 * ld.so sometimes issues anonymous map requests with non-zero 209 * pos. 210 */ 211 if (!SV_CURPROC_FLAG(SV_AOUT)) { 212 if ((size == 0 && curproc->p_osrel >= P_OSREL_MAP_ANON) || 213 ((flags & MAP_ANON) != 0 && (fd != -1 || pos != 0))) 214 return (EINVAL); 215 } else { 216 if ((flags & MAP_ANON) != 0) 217 pos = 0; 218 } 219 220 if (flags & MAP_STACK) { 221 if ((fd != -1) || 222 ((prot & (PROT_READ | PROT_WRITE)) != (PROT_READ | PROT_WRITE))) 223 return (EINVAL); 224 flags |= MAP_ANON; 225 pos = 0; 226 } 227 if ((flags & ~(MAP_SHARED | MAP_PRIVATE | MAP_FIXED | MAP_HASSEMAPHORE | 228 MAP_STACK | MAP_NOSYNC | MAP_ANON | MAP_EXCL | MAP_NOCORE | 229 MAP_PREFAULT_READ | MAP_GUARD | 230 #ifdef MAP_32BIT 231 MAP_32BIT | 232 #endif 233 MAP_ALIGNMENT_MASK)) != 0) 234 return (EINVAL); 235 if ((flags & (MAP_EXCL | MAP_FIXED)) == MAP_EXCL) 236 return (EINVAL); 237 if ((flags & (MAP_SHARED | MAP_PRIVATE)) == (MAP_SHARED | MAP_PRIVATE)) 238 return (EINVAL); 239 if (prot != PROT_NONE && 240 (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC)) != 0) 241 return (EINVAL); 242 if ((flags & MAP_GUARD) != 0 && (prot != PROT_NONE || fd != -1 || 243 pos != 0 || (flags & (MAP_SHARED | MAP_PRIVATE | MAP_PREFAULT | 244 MAP_PREFAULT_READ | MAP_ANON | MAP_STACK)) != 0)) 245 return (EINVAL); 246 247 /* 248 * Align the file position to a page boundary, 249 * and save its page offset component. 250 */ 251 pageoff = (pos & PAGE_MASK); 252 pos -= pageoff; 253 254 /* Adjust size for rounding (on both ends). */ 255 size += pageoff; /* low end... */ 256 size = (vm_size_t) round_page(size); /* hi end */ 257 258 /* Ensure alignment is at least a page and fits in a pointer. */ 259 align = flags & MAP_ALIGNMENT_MASK; 260 if (align != 0 && align != MAP_ALIGNED_SUPER && 261 (align >> MAP_ALIGNMENT_SHIFT >= sizeof(void *) * NBBY || 262 align >> MAP_ALIGNMENT_SHIFT < PAGE_SHIFT)) 263 return (EINVAL); 264 265 /* 266 * Check for illegal addresses. Watch out for address wrap... Note 267 * that VM_*_ADDRESS are not constants due to casts (argh). 268 */ 269 if (flags & MAP_FIXED) { 270 /* 271 * The specified address must have the same remainder 272 * as the file offset taken modulo PAGE_SIZE, so it 273 * should be aligned after adjustment by pageoff. 274 */ 275 addr -= pageoff; 276 if (addr & PAGE_MASK) 277 return (EINVAL); 278 279 /* Address range must be all in user VM space. */ 280 if (addr < vm_map_min(&vms->vm_map) || 281 addr + size > vm_map_max(&vms->vm_map)) 282 return (EINVAL); 283 if (addr + size < addr) 284 return (EINVAL); 285 #ifdef MAP_32BIT 286 if (flags & MAP_32BIT && addr + size > MAP_32BIT_MAX_ADDR) 287 return (EINVAL); 288 } else if (flags & MAP_32BIT) { 289 /* 290 * For MAP_32BIT, override the hint if it is too high and 291 * do not bother moving the mapping past the heap (since 292 * the heap is usually above 2GB). 293 */ 294 if (addr + size > MAP_32BIT_MAX_ADDR) 295 addr = 0; 296 #endif 297 } else { 298 /* 299 * XXX for non-fixed mappings where no hint is provided or 300 * the hint would fall in the potential heap space, 301 * place it after the end of the largest possible heap. 302 * 303 * There should really be a pmap call to determine a reasonable 304 * location. 305 */ 306 if (addr == 0 || 307 (addr >= round_page((vm_offset_t)vms->vm_taddr) && 308 addr < round_page((vm_offset_t)vms->vm_daddr + 309 lim_max(td, RLIMIT_DATA)))) 310 addr = round_page((vm_offset_t)vms->vm_daddr + 311 lim_max(td, RLIMIT_DATA)); 312 } 313 if (size == 0) { 314 /* 315 * Return success without mapping anything for old 316 * binaries that request a page-aligned mapping of 317 * length 0. For modern binaries, this function 318 * returns an error earlier. 319 */ 320 error = 0; 321 } else if ((flags & MAP_GUARD) != 0) { 322 error = vm_mmap_object(&vms->vm_map, &addr, size, VM_PROT_NONE, 323 VM_PROT_NONE, flags, NULL, pos, FALSE, td); 324 } else if ((flags & MAP_ANON) != 0) { 325 /* 326 * Mapping blank space is trivial. 327 * 328 * This relies on VM_PROT_* matching PROT_*. 329 */ 330 error = vm_mmap_object(&vms->vm_map, &addr, size, prot, 331 VM_PROT_ALL, flags, NULL, pos, FALSE, td); 332 } else { 333 /* 334 * Mapping file, get fp for validation and don't let the 335 * descriptor disappear on us if we block. Check capability 336 * rights, but also return the maximum rights to be combined 337 * with maxprot later. 338 */ 339 cap_rights_init(&rights, CAP_MMAP); 340 if (prot & PROT_READ) 341 cap_rights_set(&rights, CAP_MMAP_R); 342 if ((flags & MAP_SHARED) != 0) { 343 if (prot & PROT_WRITE) 344 cap_rights_set(&rights, CAP_MMAP_W); 345 } 346 if (prot & PROT_EXEC) 347 cap_rights_set(&rights, CAP_MMAP_X); 348 error = fget_mmap(td, fd, &rights, &cap_maxprot, &fp); 349 if (error != 0) 350 goto done; 351 if ((flags & (MAP_SHARED | MAP_PRIVATE)) == 0 && 352 td->td_proc->p_osrel >= P_OSREL_MAP_FSTRICT) { 353 error = EINVAL; 354 goto done; 355 } 356 357 /* This relies on VM_PROT_* matching PROT_*. */ 358 error = fo_mmap(fp, &vms->vm_map, &addr, size, prot, 359 cap_maxprot, flags, pos, td); 360 } 361 362 if (error == 0) 363 td->td_retval[0] = (register_t) (addr + pageoff); 364 done: 365 if (fp) 366 fdrop(fp, td); 367 368 return (error); 369 } 370 371 #if defined(COMPAT_FREEBSD6) 372 int 373 freebsd6_mmap(struct thread *td, struct freebsd6_mmap_args *uap) 374 { 375 376 return (kern_mmap(td, (uintptr_t)uap->addr, uap->len, uap->prot, 377 uap->flags, uap->fd, uap->pos)); 378 } 379 #endif 380 381 #ifdef COMPAT_43 382 #ifndef _SYS_SYSPROTO_H_ 383 struct ommap_args { 384 caddr_t addr; 385 int len; 386 int prot; 387 int flags; 388 int fd; 389 long pos; 390 }; 391 #endif 392 int 393 ommap(struct thread *td, struct ommap_args *uap) 394 { 395 static const char cvtbsdprot[8] = { 396 0, 397 PROT_EXEC, 398 PROT_WRITE, 399 PROT_EXEC | PROT_WRITE, 400 PROT_READ, 401 PROT_EXEC | PROT_READ, 402 PROT_WRITE | PROT_READ, 403 PROT_EXEC | PROT_WRITE | PROT_READ, 404 }; 405 int flags, prot; 406 407 #define OMAP_ANON 0x0002 408 #define OMAP_COPY 0x0020 409 #define OMAP_SHARED 0x0010 410 #define OMAP_FIXED 0x0100 411 412 prot = cvtbsdprot[uap->prot & 0x7]; 413 #ifdef COMPAT_FREEBSD32 414 #if defined(__amd64__) 415 if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32) && 416 prot != 0) 417 prot |= PROT_EXEC; 418 #endif 419 #endif 420 flags = 0; 421 if (uap->flags & OMAP_ANON) 422 flags |= MAP_ANON; 423 if (uap->flags & OMAP_COPY) 424 flags |= MAP_COPY; 425 if (uap->flags & OMAP_SHARED) 426 flags |= MAP_SHARED; 427 else 428 flags |= MAP_PRIVATE; 429 if (uap->flags & OMAP_FIXED) 430 flags |= MAP_FIXED; 431 return (kern_mmap(td, (uintptr_t)uap->addr, uap->len, prot, flags, 432 uap->fd, uap->pos)); 433 } 434 #endif /* COMPAT_43 */ 435 436 437 #ifndef _SYS_SYSPROTO_H_ 438 struct msync_args { 439 void *addr; 440 size_t len; 441 int flags; 442 }; 443 #endif 444 int 445 sys_msync(struct thread *td, struct msync_args *uap) 446 { 447 448 return (kern_msync(td, (uintptr_t)uap->addr, uap->len, uap->flags)); 449 } 450 451 int 452 kern_msync(struct thread *td, uintptr_t addr0, size_t size, int flags) 453 { 454 vm_offset_t addr; 455 vm_size_t pageoff; 456 vm_map_t map; 457 int rv; 458 459 addr = addr0; 460 pageoff = (addr & PAGE_MASK); 461 addr -= pageoff; 462 size += pageoff; 463 size = (vm_size_t) round_page(size); 464 if (addr + size < addr) 465 return (EINVAL); 466 467 if ((flags & (MS_ASYNC|MS_INVALIDATE)) == (MS_ASYNC|MS_INVALIDATE)) 468 return (EINVAL); 469 470 map = &td->td_proc->p_vmspace->vm_map; 471 472 /* 473 * Clean the pages and interpret the return value. 474 */ 475 rv = vm_map_sync(map, addr, addr + size, (flags & MS_ASYNC) == 0, 476 (flags & MS_INVALIDATE) != 0); 477 switch (rv) { 478 case KERN_SUCCESS: 479 return (0); 480 case KERN_INVALID_ADDRESS: 481 return (ENOMEM); 482 case KERN_INVALID_ARGUMENT: 483 return (EBUSY); 484 case KERN_FAILURE: 485 return (EIO); 486 default: 487 return (EINVAL); 488 } 489 } 490 491 #ifndef _SYS_SYSPROTO_H_ 492 struct munmap_args { 493 void *addr; 494 size_t len; 495 }; 496 #endif 497 int 498 sys_munmap(struct thread *td, struct munmap_args *uap) 499 { 500 501 return (kern_munmap(td, (uintptr_t)uap->addr, uap->len)); 502 } 503 504 int 505 kern_munmap(struct thread *td, uintptr_t addr0, size_t size) 506 { 507 #ifdef HWPMC_HOOKS 508 struct pmckern_map_out pkm; 509 vm_map_entry_t entry; 510 bool pmc_handled; 511 #endif 512 vm_offset_t addr; 513 vm_size_t pageoff; 514 vm_map_t map; 515 516 if (size == 0) 517 return (EINVAL); 518 519 addr = addr0; 520 pageoff = (addr & PAGE_MASK); 521 addr -= pageoff; 522 size += pageoff; 523 size = (vm_size_t) round_page(size); 524 if (addr + size < addr) 525 return (EINVAL); 526 527 /* 528 * Check for illegal addresses. Watch out for address wrap... 529 */ 530 map = &td->td_proc->p_vmspace->vm_map; 531 if (addr < vm_map_min(map) || addr + size > vm_map_max(map)) 532 return (EINVAL); 533 vm_map_lock(map); 534 #ifdef HWPMC_HOOKS 535 pmc_handled = false; 536 if (PMC_HOOK_INSTALLED(PMC_FN_MUNMAP)) { 537 pmc_handled = true; 538 /* 539 * Inform hwpmc if the address range being unmapped contains 540 * an executable region. 541 */ 542 pkm.pm_address = (uintptr_t) NULL; 543 if (vm_map_lookup_entry(map, addr, &entry)) { 544 for (; 545 entry != &map->header && entry->start < addr + size; 546 entry = entry->next) { 547 if (vm_map_check_protection(map, entry->start, 548 entry->end, VM_PROT_EXECUTE) == TRUE) { 549 pkm.pm_address = (uintptr_t) addr; 550 pkm.pm_size = (size_t) size; 551 break; 552 } 553 } 554 } 555 } 556 #endif 557 vm_map_delete(map, addr, addr + size); 558 559 #ifdef HWPMC_HOOKS 560 if (__predict_false(pmc_handled)) { 561 /* downgrade the lock to prevent a LOR with the pmc-sx lock */ 562 vm_map_lock_downgrade(map); 563 if (pkm.pm_address != (uintptr_t) NULL) 564 PMC_CALL_HOOK(td, PMC_FN_MUNMAP, (void *) &pkm); 565 vm_map_unlock_read(map); 566 } else 567 #endif 568 vm_map_unlock(map); 569 570 /* vm_map_delete returns nothing but KERN_SUCCESS anyway */ 571 return (0); 572 } 573 574 #ifndef _SYS_SYSPROTO_H_ 575 struct mprotect_args { 576 const void *addr; 577 size_t len; 578 int prot; 579 }; 580 #endif 581 int 582 sys_mprotect(struct thread *td, struct mprotect_args *uap) 583 { 584 585 return (kern_mprotect(td, (uintptr_t)uap->addr, uap->len, uap->prot)); 586 } 587 588 int 589 kern_mprotect(struct thread *td, uintptr_t addr0, size_t size, int prot) 590 { 591 vm_offset_t addr; 592 vm_size_t pageoff; 593 594 addr = addr0; 595 prot = (prot & VM_PROT_ALL); 596 pageoff = (addr & PAGE_MASK); 597 addr -= pageoff; 598 size += pageoff; 599 size = (vm_size_t) round_page(size); 600 if (addr + size < addr) 601 return (EINVAL); 602 603 switch (vm_map_protect(&td->td_proc->p_vmspace->vm_map, addr, 604 addr + size, prot, FALSE)) { 605 case KERN_SUCCESS: 606 return (0); 607 case KERN_PROTECTION_FAILURE: 608 return (EACCES); 609 case KERN_RESOURCE_SHORTAGE: 610 return (ENOMEM); 611 } 612 return (EINVAL); 613 } 614 615 #ifndef _SYS_SYSPROTO_H_ 616 struct minherit_args { 617 void *addr; 618 size_t len; 619 int inherit; 620 }; 621 #endif 622 int 623 sys_minherit(struct thread *td, struct minherit_args *uap) 624 { 625 vm_offset_t addr; 626 vm_size_t size, pageoff; 627 vm_inherit_t inherit; 628 629 addr = (vm_offset_t)uap->addr; 630 size = uap->len; 631 inherit = uap->inherit; 632 633 pageoff = (addr & PAGE_MASK); 634 addr -= pageoff; 635 size += pageoff; 636 size = (vm_size_t) round_page(size); 637 if (addr + size < addr) 638 return (EINVAL); 639 640 switch (vm_map_inherit(&td->td_proc->p_vmspace->vm_map, addr, 641 addr + size, inherit)) { 642 case KERN_SUCCESS: 643 return (0); 644 case KERN_PROTECTION_FAILURE: 645 return (EACCES); 646 } 647 return (EINVAL); 648 } 649 650 #ifndef _SYS_SYSPROTO_H_ 651 struct madvise_args { 652 void *addr; 653 size_t len; 654 int behav; 655 }; 656 #endif 657 658 int 659 sys_madvise(struct thread *td, struct madvise_args *uap) 660 { 661 662 return (kern_madvise(td, (uintptr_t)uap->addr, uap->len, uap->behav)); 663 } 664 665 int 666 kern_madvise(struct thread *td, uintptr_t addr0, size_t len, int behav) 667 { 668 vm_map_t map; 669 vm_offset_t addr, end, start; 670 int flags; 671 672 /* 673 * Check for our special case, advising the swap pager we are 674 * "immortal." 675 */ 676 if (behav == MADV_PROTECT) { 677 flags = PPROT_SET; 678 return (kern_procctl(td, P_PID, td->td_proc->p_pid, 679 PROC_SPROTECT, &flags)); 680 } 681 682 /* 683 * Check for illegal behavior 684 */ 685 if (behav < 0 || behav > MADV_CORE) 686 return (EINVAL); 687 /* 688 * Check for illegal addresses. Watch out for address wrap... Note 689 * that VM_*_ADDRESS are not constants due to casts (argh). 690 */ 691 map = &td->td_proc->p_vmspace->vm_map; 692 addr = addr0; 693 if (addr < vm_map_min(map) || addr + len > vm_map_max(map)) 694 return (EINVAL); 695 if ((addr + len) < addr) 696 return (EINVAL); 697 698 /* 699 * Since this routine is only advisory, we default to conservative 700 * behavior. 701 */ 702 start = trunc_page(addr); 703 end = round_page(addr + len); 704 705 if (vm_map_madvise(map, start, end, behav)) 706 return (EINVAL); 707 return (0); 708 } 709 710 #ifndef _SYS_SYSPROTO_H_ 711 struct mincore_args { 712 const void *addr; 713 size_t len; 714 char *vec; 715 }; 716 #endif 717 718 int 719 sys_mincore(struct thread *td, struct mincore_args *uap) 720 { 721 722 return (kern_mincore(td, (uintptr_t)uap->addr, uap->len, uap->vec)); 723 } 724 725 int 726 kern_mincore(struct thread *td, uintptr_t addr0, size_t len, char *vec) 727 { 728 vm_offset_t addr, first_addr; 729 vm_offset_t end, cend; 730 pmap_t pmap; 731 vm_map_t map; 732 int error = 0; 733 int vecindex, lastvecindex; 734 vm_map_entry_t current; 735 vm_map_entry_t entry; 736 vm_object_t object; 737 vm_paddr_t locked_pa; 738 vm_page_t m; 739 vm_pindex_t pindex; 740 int mincoreinfo; 741 unsigned int timestamp; 742 boolean_t locked; 743 744 /* 745 * Make sure that the addresses presented are valid for user 746 * mode. 747 */ 748 first_addr = addr = trunc_page(addr0); 749 end = addr + (vm_size_t)round_page(len); 750 map = &td->td_proc->p_vmspace->vm_map; 751 if (end > vm_map_max(map) || end < addr) 752 return (ENOMEM); 753 754 pmap = vmspace_pmap(td->td_proc->p_vmspace); 755 756 vm_map_lock_read(map); 757 RestartScan: 758 timestamp = map->timestamp; 759 760 if (!vm_map_lookup_entry(map, addr, &entry)) { 761 vm_map_unlock_read(map); 762 return (ENOMEM); 763 } 764 765 /* 766 * Do this on a map entry basis so that if the pages are not 767 * in the current processes address space, we can easily look 768 * up the pages elsewhere. 769 */ 770 lastvecindex = -1; 771 for (current = entry; 772 (current != &map->header) && (current->start < end); 773 current = current->next) { 774 775 /* 776 * check for contiguity 777 */ 778 if (current->end < end && 779 (entry->next == &map->header || 780 current->next->start > current->end)) { 781 vm_map_unlock_read(map); 782 return (ENOMEM); 783 } 784 785 /* 786 * ignore submaps (for now) or null objects 787 */ 788 if ((current->eflags & MAP_ENTRY_IS_SUB_MAP) || 789 current->object.vm_object == NULL) 790 continue; 791 792 /* 793 * limit this scan to the current map entry and the 794 * limits for the mincore call 795 */ 796 if (addr < current->start) 797 addr = current->start; 798 cend = current->end; 799 if (cend > end) 800 cend = end; 801 802 /* 803 * scan this entry one page at a time 804 */ 805 while (addr < cend) { 806 /* 807 * Check pmap first, it is likely faster, also 808 * it can provide info as to whether we are the 809 * one referencing or modifying the page. 810 */ 811 object = NULL; 812 locked_pa = 0; 813 retry: 814 m = NULL; 815 mincoreinfo = pmap_mincore(pmap, addr, &locked_pa); 816 if (locked_pa != 0) { 817 /* 818 * The page is mapped by this process but not 819 * both accessed and modified. It is also 820 * managed. Acquire the object lock so that 821 * other mappings might be examined. 822 */ 823 m = PHYS_TO_VM_PAGE(locked_pa); 824 if (m->object != object) { 825 if (object != NULL) 826 VM_OBJECT_WUNLOCK(object); 827 object = m->object; 828 locked = VM_OBJECT_TRYWLOCK(object); 829 vm_page_unlock(m); 830 if (!locked) { 831 VM_OBJECT_WLOCK(object); 832 vm_page_lock(m); 833 goto retry; 834 } 835 } else 836 vm_page_unlock(m); 837 KASSERT(m->valid == VM_PAGE_BITS_ALL, 838 ("mincore: page %p is mapped but invalid", 839 m)); 840 } else if (mincoreinfo == 0) { 841 /* 842 * The page is not mapped by this process. If 843 * the object implements managed pages, then 844 * determine if the page is resident so that 845 * the mappings might be examined. 846 */ 847 if (current->object.vm_object != object) { 848 if (object != NULL) 849 VM_OBJECT_WUNLOCK(object); 850 object = current->object.vm_object; 851 VM_OBJECT_WLOCK(object); 852 } 853 if (object->type == OBJT_DEFAULT || 854 object->type == OBJT_SWAP || 855 object->type == OBJT_VNODE) { 856 pindex = OFF_TO_IDX(current->offset + 857 (addr - current->start)); 858 m = vm_page_lookup(object, pindex); 859 if (m != NULL && m->valid == 0) 860 m = NULL; 861 if (m != NULL) 862 mincoreinfo = MINCORE_INCORE; 863 } 864 } 865 if (m != NULL) { 866 /* Examine other mappings to the page. */ 867 if (m->dirty == 0 && pmap_is_modified(m)) 868 vm_page_dirty(m); 869 if (m->dirty != 0) 870 mincoreinfo |= MINCORE_MODIFIED_OTHER; 871 /* 872 * The first test for PGA_REFERENCED is an 873 * optimization. The second test is 874 * required because a concurrent pmap 875 * operation could clear the last reference 876 * and set PGA_REFERENCED before the call to 877 * pmap_is_referenced(). 878 */ 879 if ((m->aflags & PGA_REFERENCED) != 0 || 880 pmap_is_referenced(m) || 881 (m->aflags & PGA_REFERENCED) != 0) 882 mincoreinfo |= MINCORE_REFERENCED_OTHER; 883 } 884 if (object != NULL) 885 VM_OBJECT_WUNLOCK(object); 886 887 /* 888 * subyte may page fault. In case it needs to modify 889 * the map, we release the lock. 890 */ 891 vm_map_unlock_read(map); 892 893 /* 894 * calculate index into user supplied byte vector 895 */ 896 vecindex = atop(addr - first_addr); 897 898 /* 899 * If we have skipped map entries, we need to make sure that 900 * the byte vector is zeroed for those skipped entries. 901 */ 902 while ((lastvecindex + 1) < vecindex) { 903 ++lastvecindex; 904 error = subyte(vec + lastvecindex, 0); 905 if (error) { 906 error = EFAULT; 907 goto done2; 908 } 909 } 910 911 /* 912 * Pass the page information to the user 913 */ 914 error = subyte(vec + vecindex, mincoreinfo); 915 if (error) { 916 error = EFAULT; 917 goto done2; 918 } 919 920 /* 921 * If the map has changed, due to the subyte, the previous 922 * output may be invalid. 923 */ 924 vm_map_lock_read(map); 925 if (timestamp != map->timestamp) 926 goto RestartScan; 927 928 lastvecindex = vecindex; 929 addr += PAGE_SIZE; 930 } 931 } 932 933 /* 934 * subyte may page fault. In case it needs to modify 935 * the map, we release the lock. 936 */ 937 vm_map_unlock_read(map); 938 939 /* 940 * Zero the last entries in the byte vector. 941 */ 942 vecindex = atop(end - first_addr); 943 while ((lastvecindex + 1) < vecindex) { 944 ++lastvecindex; 945 error = subyte(vec + lastvecindex, 0); 946 if (error) { 947 error = EFAULT; 948 goto done2; 949 } 950 } 951 952 /* 953 * If the map has changed, due to the subyte, the previous 954 * output may be invalid. 955 */ 956 vm_map_lock_read(map); 957 if (timestamp != map->timestamp) 958 goto RestartScan; 959 vm_map_unlock_read(map); 960 done2: 961 return (error); 962 } 963 964 #ifndef _SYS_SYSPROTO_H_ 965 struct mlock_args { 966 const void *addr; 967 size_t len; 968 }; 969 #endif 970 int 971 sys_mlock(struct thread *td, struct mlock_args *uap) 972 { 973 974 return (kern_mlock(td->td_proc, td->td_ucred, 975 __DECONST(uintptr_t, uap->addr), uap->len)); 976 } 977 978 int 979 kern_mlock(struct proc *proc, struct ucred *cred, uintptr_t addr0, size_t len) 980 { 981 vm_offset_t addr, end, last, start; 982 vm_size_t npages, size; 983 vm_map_t map; 984 unsigned long nsize; 985 int error; 986 987 error = priv_check_cred(cred, PRIV_VM_MLOCK, 0); 988 if (error) 989 return (error); 990 addr = addr0; 991 size = len; 992 last = addr + size; 993 start = trunc_page(addr); 994 end = round_page(last); 995 if (last < addr || end < addr) 996 return (EINVAL); 997 npages = atop(end - start); 998 if (npages > vm_page_max_wired) 999 return (ENOMEM); 1000 map = &proc->p_vmspace->vm_map; 1001 PROC_LOCK(proc); 1002 nsize = ptoa(npages + pmap_wired_count(map->pmap)); 1003 if (nsize > lim_cur_proc(proc, RLIMIT_MEMLOCK)) { 1004 PROC_UNLOCK(proc); 1005 return (ENOMEM); 1006 } 1007 PROC_UNLOCK(proc); 1008 if (npages + vm_cnt.v_wire_count > vm_page_max_wired) 1009 return (EAGAIN); 1010 #ifdef RACCT 1011 if (racct_enable) { 1012 PROC_LOCK(proc); 1013 error = racct_set(proc, RACCT_MEMLOCK, nsize); 1014 PROC_UNLOCK(proc); 1015 if (error != 0) 1016 return (ENOMEM); 1017 } 1018 #endif 1019 error = vm_map_wire(map, start, end, 1020 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); 1021 #ifdef RACCT 1022 if (racct_enable && error != KERN_SUCCESS) { 1023 PROC_LOCK(proc); 1024 racct_set(proc, RACCT_MEMLOCK, 1025 ptoa(pmap_wired_count(map->pmap))); 1026 PROC_UNLOCK(proc); 1027 } 1028 #endif 1029 return (error == KERN_SUCCESS ? 0 : ENOMEM); 1030 } 1031 1032 #ifndef _SYS_SYSPROTO_H_ 1033 struct mlockall_args { 1034 int how; 1035 }; 1036 #endif 1037 1038 int 1039 sys_mlockall(struct thread *td, struct mlockall_args *uap) 1040 { 1041 vm_map_t map; 1042 int error; 1043 1044 map = &td->td_proc->p_vmspace->vm_map; 1045 error = priv_check(td, PRIV_VM_MLOCK); 1046 if (error) 1047 return (error); 1048 1049 if ((uap->how == 0) || ((uap->how & ~(MCL_CURRENT|MCL_FUTURE)) != 0)) 1050 return (EINVAL); 1051 1052 /* 1053 * If wiring all pages in the process would cause it to exceed 1054 * a hard resource limit, return ENOMEM. 1055 */ 1056 if (!old_mlock && uap->how & MCL_CURRENT) { 1057 PROC_LOCK(td->td_proc); 1058 if (map->size > lim_cur(td, RLIMIT_MEMLOCK)) { 1059 PROC_UNLOCK(td->td_proc); 1060 return (ENOMEM); 1061 } 1062 PROC_UNLOCK(td->td_proc); 1063 } 1064 #ifdef RACCT 1065 if (racct_enable) { 1066 PROC_LOCK(td->td_proc); 1067 error = racct_set(td->td_proc, RACCT_MEMLOCK, map->size); 1068 PROC_UNLOCK(td->td_proc); 1069 if (error != 0) 1070 return (ENOMEM); 1071 } 1072 #endif 1073 1074 if (uap->how & MCL_FUTURE) { 1075 vm_map_lock(map); 1076 vm_map_modflags(map, MAP_WIREFUTURE, 0); 1077 vm_map_unlock(map); 1078 error = 0; 1079 } 1080 1081 if (uap->how & MCL_CURRENT) { 1082 /* 1083 * P1003.1-2001 mandates that all currently mapped pages 1084 * will be memory resident and locked (wired) upon return 1085 * from mlockall(). vm_map_wire() will wire pages, by 1086 * calling vm_fault_wire() for each page in the region. 1087 */ 1088 error = vm_map_wire(map, vm_map_min(map), vm_map_max(map), 1089 VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); 1090 error = (error == KERN_SUCCESS ? 0 : EAGAIN); 1091 } 1092 #ifdef RACCT 1093 if (racct_enable && error != KERN_SUCCESS) { 1094 PROC_LOCK(td->td_proc); 1095 racct_set(td->td_proc, RACCT_MEMLOCK, 1096 ptoa(pmap_wired_count(map->pmap))); 1097 PROC_UNLOCK(td->td_proc); 1098 } 1099 #endif 1100 1101 return (error); 1102 } 1103 1104 #ifndef _SYS_SYSPROTO_H_ 1105 struct munlockall_args { 1106 register_t dummy; 1107 }; 1108 #endif 1109 1110 int 1111 sys_munlockall(struct thread *td, struct munlockall_args *uap) 1112 { 1113 vm_map_t map; 1114 int error; 1115 1116 map = &td->td_proc->p_vmspace->vm_map; 1117 error = priv_check(td, PRIV_VM_MUNLOCK); 1118 if (error) 1119 return (error); 1120 1121 /* Clear the MAP_WIREFUTURE flag from this vm_map. */ 1122 vm_map_lock(map); 1123 vm_map_modflags(map, 0, MAP_WIREFUTURE); 1124 vm_map_unlock(map); 1125 1126 /* Forcibly unwire all pages. */ 1127 error = vm_map_unwire(map, vm_map_min(map), vm_map_max(map), 1128 VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); 1129 #ifdef RACCT 1130 if (racct_enable && error == KERN_SUCCESS) { 1131 PROC_LOCK(td->td_proc); 1132 racct_set(td->td_proc, RACCT_MEMLOCK, 0); 1133 PROC_UNLOCK(td->td_proc); 1134 } 1135 #endif 1136 1137 return (error); 1138 } 1139 1140 #ifndef _SYS_SYSPROTO_H_ 1141 struct munlock_args { 1142 const void *addr; 1143 size_t len; 1144 }; 1145 #endif 1146 int 1147 sys_munlock(struct thread *td, struct munlock_args *uap) 1148 { 1149 1150 return (kern_munlock(td, (uintptr_t)uap->addr, uap->len)); 1151 } 1152 1153 int 1154 kern_munlock(struct thread *td, uintptr_t addr0, size_t size) 1155 { 1156 vm_offset_t addr, end, last, start; 1157 #ifdef RACCT 1158 vm_map_t map; 1159 #endif 1160 int error; 1161 1162 error = priv_check(td, PRIV_VM_MUNLOCK); 1163 if (error) 1164 return (error); 1165 addr = addr0; 1166 last = addr + size; 1167 start = trunc_page(addr); 1168 end = round_page(last); 1169 if (last < addr || end < addr) 1170 return (EINVAL); 1171 error = vm_map_unwire(&td->td_proc->p_vmspace->vm_map, start, end, 1172 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); 1173 #ifdef RACCT 1174 if (racct_enable && error == KERN_SUCCESS) { 1175 PROC_LOCK(td->td_proc); 1176 map = &td->td_proc->p_vmspace->vm_map; 1177 racct_set(td->td_proc, RACCT_MEMLOCK, 1178 ptoa(pmap_wired_count(map->pmap))); 1179 PROC_UNLOCK(td->td_proc); 1180 } 1181 #endif 1182 return (error == KERN_SUCCESS ? 0 : ENOMEM); 1183 } 1184 1185 /* 1186 * vm_mmap_vnode() 1187 * 1188 * Helper function for vm_mmap. Perform sanity check specific for mmap 1189 * operations on vnodes. 1190 */ 1191 int 1192 vm_mmap_vnode(struct thread *td, vm_size_t objsize, 1193 vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, 1194 struct vnode *vp, vm_ooffset_t *foffp, vm_object_t *objp, 1195 boolean_t *writecounted) 1196 { 1197 struct vattr va; 1198 vm_object_t obj; 1199 vm_offset_t foff; 1200 struct ucred *cred; 1201 int error, flags, locktype; 1202 1203 cred = td->td_ucred; 1204 if ((*maxprotp & VM_PROT_WRITE) && (*flagsp & MAP_SHARED)) 1205 locktype = LK_EXCLUSIVE; 1206 else 1207 locktype = LK_SHARED; 1208 if ((error = vget(vp, locktype, td)) != 0) 1209 return (error); 1210 AUDIT_ARG_VNODE1(vp); 1211 foff = *foffp; 1212 flags = *flagsp; 1213 obj = vp->v_object; 1214 if (vp->v_type == VREG) { 1215 /* 1216 * Get the proper underlying object 1217 */ 1218 if (obj == NULL) { 1219 error = EINVAL; 1220 goto done; 1221 } 1222 if (obj->type == OBJT_VNODE && obj->handle != vp) { 1223 vput(vp); 1224 vp = (struct vnode *)obj->handle; 1225 /* 1226 * Bypass filesystems obey the mpsafety of the 1227 * underlying fs. Tmpfs never bypasses. 1228 */ 1229 error = vget(vp, locktype, td); 1230 if (error != 0) 1231 return (error); 1232 } 1233 if (locktype == LK_EXCLUSIVE) { 1234 *writecounted = TRUE; 1235 vnode_pager_update_writecount(obj, 0, objsize); 1236 } 1237 } else { 1238 error = EINVAL; 1239 goto done; 1240 } 1241 if ((error = VOP_GETATTR(vp, &va, cred))) 1242 goto done; 1243 #ifdef MAC 1244 /* This relies on VM_PROT_* matching PROT_*. */ 1245 error = mac_vnode_check_mmap(cred, vp, (int)prot, flags); 1246 if (error != 0) 1247 goto done; 1248 #endif 1249 if ((flags & MAP_SHARED) != 0) { 1250 if ((va.va_flags & (SF_SNAPSHOT|IMMUTABLE|APPEND)) != 0) { 1251 if (prot & VM_PROT_WRITE) { 1252 error = EPERM; 1253 goto done; 1254 } 1255 *maxprotp &= ~VM_PROT_WRITE; 1256 } 1257 } 1258 /* 1259 * If it is a regular file without any references 1260 * we do not need to sync it. 1261 * Adjust object size to be the size of actual file. 1262 */ 1263 objsize = round_page(va.va_size); 1264 if (va.va_nlink == 0) 1265 flags |= MAP_NOSYNC; 1266 if (obj->type == OBJT_VNODE) { 1267 obj = vm_pager_allocate(OBJT_VNODE, vp, objsize, prot, foff, 1268 cred); 1269 if (obj == NULL) { 1270 error = ENOMEM; 1271 goto done; 1272 } 1273 } else { 1274 KASSERT(obj->type == OBJT_DEFAULT || obj->type == OBJT_SWAP, 1275 ("wrong object type")); 1276 VM_OBJECT_WLOCK(obj); 1277 vm_object_reference_locked(obj); 1278 #if VM_NRESERVLEVEL > 0 1279 vm_object_color(obj, 0); 1280 #endif 1281 VM_OBJECT_WUNLOCK(obj); 1282 } 1283 *objp = obj; 1284 *flagsp = flags; 1285 1286 vfs_mark_atime(vp, cred); 1287 1288 done: 1289 if (error != 0 && *writecounted) { 1290 *writecounted = FALSE; 1291 vnode_pager_update_writecount(obj, objsize, 0); 1292 } 1293 vput(vp); 1294 return (error); 1295 } 1296 1297 /* 1298 * vm_mmap_cdev() 1299 * 1300 * Helper function for vm_mmap. Perform sanity check specific for mmap 1301 * operations on cdevs. 1302 */ 1303 int 1304 vm_mmap_cdev(struct thread *td, vm_size_t objsize, vm_prot_t prot, 1305 vm_prot_t *maxprotp, int *flagsp, struct cdev *cdev, struct cdevsw *dsw, 1306 vm_ooffset_t *foff, vm_object_t *objp) 1307 { 1308 vm_object_t obj; 1309 int error, flags; 1310 1311 flags = *flagsp; 1312 1313 if (dsw->d_flags & D_MMAP_ANON) { 1314 *objp = NULL; 1315 *foff = 0; 1316 *maxprotp = VM_PROT_ALL; 1317 *flagsp |= MAP_ANON; 1318 return (0); 1319 } 1320 /* 1321 * cdevs do not provide private mappings of any kind. 1322 */ 1323 if ((*maxprotp & VM_PROT_WRITE) == 0 && 1324 (prot & VM_PROT_WRITE) != 0) 1325 return (EACCES); 1326 if (flags & (MAP_PRIVATE|MAP_COPY)) 1327 return (EINVAL); 1328 /* 1329 * Force device mappings to be shared. 1330 */ 1331 flags |= MAP_SHARED; 1332 #ifdef MAC_XXX 1333 error = mac_cdev_check_mmap(td->td_ucred, cdev, (int)prot); 1334 if (error != 0) 1335 return (error); 1336 #endif 1337 /* 1338 * First, try d_mmap_single(). If that is not implemented 1339 * (returns ENODEV), fall back to using the device pager. 1340 * Note that d_mmap_single() must return a reference to the 1341 * object (it needs to bump the reference count of the object 1342 * it returns somehow). 1343 * 1344 * XXX assumes VM_PROT_* == PROT_* 1345 */ 1346 error = dsw->d_mmap_single(cdev, foff, objsize, objp, (int)prot); 1347 if (error != ENODEV) 1348 return (error); 1349 obj = vm_pager_allocate(OBJT_DEVICE, cdev, objsize, prot, *foff, 1350 td->td_ucred); 1351 if (obj == NULL) 1352 return (EINVAL); 1353 *objp = obj; 1354 *flagsp = flags; 1355 return (0); 1356 } 1357 1358 /* 1359 * vm_mmap() 1360 * 1361 * Internal version of mmap used by exec, sys5 shared memory, and 1362 * various device drivers. Handle is either a vnode pointer, a 1363 * character device, or NULL for MAP_ANON. 1364 */ 1365 int 1366 vm_mmap(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, 1367 vm_prot_t maxprot, int flags, 1368 objtype_t handle_type, void *handle, 1369 vm_ooffset_t foff) 1370 { 1371 vm_object_t object; 1372 struct thread *td = curthread; 1373 int error; 1374 boolean_t writecounted; 1375 1376 if (size == 0) 1377 return (EINVAL); 1378 1379 size = round_page(size); 1380 object = NULL; 1381 writecounted = FALSE; 1382 1383 /* 1384 * Lookup/allocate object. 1385 */ 1386 switch (handle_type) { 1387 case OBJT_DEVICE: { 1388 struct cdevsw *dsw; 1389 struct cdev *cdev; 1390 int ref; 1391 1392 cdev = handle; 1393 dsw = dev_refthread(cdev, &ref); 1394 if (dsw == NULL) 1395 return (ENXIO); 1396 error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, cdev, 1397 dsw, &foff, &object); 1398 dev_relthread(cdev, ref); 1399 break; 1400 } 1401 case OBJT_VNODE: 1402 error = vm_mmap_vnode(td, size, prot, &maxprot, &flags, 1403 handle, &foff, &object, &writecounted); 1404 break; 1405 case OBJT_DEFAULT: 1406 if (handle == NULL) { 1407 error = 0; 1408 break; 1409 } 1410 /* FALLTHROUGH */ 1411 default: 1412 error = EINVAL; 1413 break; 1414 } 1415 if (error) 1416 return (error); 1417 1418 error = vm_mmap_object(map, addr, size, prot, maxprot, flags, object, 1419 foff, writecounted, td); 1420 if (error != 0 && object != NULL) { 1421 /* 1422 * If this mapping was accounted for in the vnode's 1423 * writecount, then undo that now. 1424 */ 1425 if (writecounted) 1426 vnode_pager_release_writecount(object, 0, size); 1427 vm_object_deallocate(object); 1428 } 1429 return (error); 1430 } 1431 1432 /* 1433 * Internal version of mmap that maps a specific VM object into an 1434 * map. Called by mmap for MAP_ANON, vm_mmap, shm_mmap, and vn_mmap. 1435 */ 1436 int 1437 vm_mmap_object(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, 1438 vm_prot_t maxprot, int flags, vm_object_t object, vm_ooffset_t foff, 1439 boolean_t writecounted, struct thread *td) 1440 { 1441 boolean_t curmap, fitit; 1442 vm_offset_t max_addr; 1443 int docow, error, findspace, rv; 1444 1445 curmap = map == &td->td_proc->p_vmspace->vm_map; 1446 if (curmap) { 1447 PROC_LOCK(td->td_proc); 1448 if (map->size + size > lim_cur_proc(td->td_proc, RLIMIT_VMEM)) { 1449 PROC_UNLOCK(td->td_proc); 1450 return (ENOMEM); 1451 } 1452 if (racct_set(td->td_proc, RACCT_VMEM, map->size + size)) { 1453 PROC_UNLOCK(td->td_proc); 1454 return (ENOMEM); 1455 } 1456 if (!old_mlock && map->flags & MAP_WIREFUTURE) { 1457 if (ptoa(pmap_wired_count(map->pmap)) + size > 1458 lim_cur_proc(td->td_proc, RLIMIT_MEMLOCK)) { 1459 racct_set_force(td->td_proc, RACCT_VMEM, 1460 map->size); 1461 PROC_UNLOCK(td->td_proc); 1462 return (ENOMEM); 1463 } 1464 error = racct_set(td->td_proc, RACCT_MEMLOCK, 1465 ptoa(pmap_wired_count(map->pmap)) + size); 1466 if (error != 0) { 1467 racct_set_force(td->td_proc, RACCT_VMEM, 1468 map->size); 1469 PROC_UNLOCK(td->td_proc); 1470 return (error); 1471 } 1472 } 1473 PROC_UNLOCK(td->td_proc); 1474 } 1475 1476 /* 1477 * We currently can only deal with page aligned file offsets. 1478 * The mmap() system call already enforces this by subtracting 1479 * the page offset from the file offset, but checking here 1480 * catches errors in device drivers (e.g. d_single_mmap() 1481 * callbacks) and other internal mapping requests (such as in 1482 * exec). 1483 */ 1484 if (foff & PAGE_MASK) 1485 return (EINVAL); 1486 1487 if ((flags & MAP_FIXED) == 0) { 1488 fitit = TRUE; 1489 *addr = round_page(*addr); 1490 } else { 1491 if (*addr != trunc_page(*addr)) 1492 return (EINVAL); 1493 fitit = FALSE; 1494 } 1495 1496 if (flags & MAP_ANON) { 1497 if (object != NULL || foff != 0) 1498 return (EINVAL); 1499 docow = 0; 1500 } else if (flags & MAP_PREFAULT_READ) 1501 docow = MAP_PREFAULT; 1502 else 1503 docow = MAP_PREFAULT_PARTIAL; 1504 1505 if ((flags & (MAP_ANON|MAP_SHARED)) == 0) 1506 docow |= MAP_COPY_ON_WRITE; 1507 if (flags & MAP_NOSYNC) 1508 docow |= MAP_DISABLE_SYNCER; 1509 if (flags & MAP_NOCORE) 1510 docow |= MAP_DISABLE_COREDUMP; 1511 /* Shared memory is also shared with children. */ 1512 if (flags & MAP_SHARED) 1513 docow |= MAP_INHERIT_SHARE; 1514 if (writecounted) 1515 docow |= MAP_VN_WRITECOUNT; 1516 if (flags & MAP_STACK) { 1517 if (object != NULL) 1518 return (EINVAL); 1519 docow |= MAP_STACK_GROWS_DOWN; 1520 } 1521 if ((flags & MAP_EXCL) != 0) 1522 docow |= MAP_CHECK_EXCL; 1523 if ((flags & MAP_GUARD) != 0) 1524 docow |= MAP_CREATE_GUARD; 1525 1526 if (fitit) { 1527 if ((flags & MAP_ALIGNMENT_MASK) == MAP_ALIGNED_SUPER) 1528 findspace = VMFS_SUPER_SPACE; 1529 else if ((flags & MAP_ALIGNMENT_MASK) != 0) 1530 findspace = VMFS_ALIGNED_SPACE(flags >> 1531 MAP_ALIGNMENT_SHIFT); 1532 else 1533 findspace = VMFS_OPTIMAL_SPACE; 1534 max_addr = 0; 1535 #ifdef MAP_32BIT 1536 if ((flags & MAP_32BIT) != 0) 1537 max_addr = MAP_32BIT_MAX_ADDR; 1538 #endif 1539 if (curmap) { 1540 rv = vm_map_find_min(map, object, foff, addr, size, 1541 round_page((vm_offset_t)td->td_proc->p_vmspace-> 1542 vm_daddr + lim_max(td, RLIMIT_DATA)), max_addr, 1543 findspace, prot, maxprot, docow); 1544 } else { 1545 rv = vm_map_find(map, object, foff, addr, size, 1546 max_addr, findspace, prot, maxprot, docow); 1547 } 1548 } else { 1549 rv = vm_map_fixed(map, object, foff, *addr, size, 1550 prot, maxprot, docow); 1551 } 1552 1553 if (rv == KERN_SUCCESS) { 1554 /* 1555 * If the process has requested that all future mappings 1556 * be wired, then heed this. 1557 */ 1558 if (map->flags & MAP_WIREFUTURE) { 1559 vm_map_wire(map, *addr, *addr + size, 1560 VM_MAP_WIRE_USER | ((flags & MAP_STACK) ? 1561 VM_MAP_WIRE_HOLESOK : VM_MAP_WIRE_NOHOLES)); 1562 } 1563 } 1564 return (vm_mmap_to_errno(rv)); 1565 } 1566 1567 /* 1568 * Translate a Mach VM return code to zero on success or the appropriate errno 1569 * on failure. 1570 */ 1571 int 1572 vm_mmap_to_errno(int rv) 1573 { 1574 1575 switch (rv) { 1576 case KERN_SUCCESS: 1577 return (0); 1578 case KERN_INVALID_ADDRESS: 1579 case KERN_NO_SPACE: 1580 return (ENOMEM); 1581 case KERN_PROTECTION_FAILURE: 1582 return (EACCES); 1583 default: 1584 return (EINVAL); 1585 } 1586 }
Cache object: f3a2c574f3644733f35a0a4364bec9ef
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