1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1988 University of Utah. 5 * Copyright (c) 1991, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * the Systems Programming Group of the University of Utah Computer 10 * Science Department. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$ 37 * 38 * @(#)vm_mmap.c 8.4 (Berkeley) 1/12/94 39 */ 40 41 /* 42 * Mapped file (mmap) interface to VM 43 */ 44 45 #include <sys/cdefs.h> 46 __FBSDID("$FreeBSD$"); 47 48 #include "opt_hwpmc_hooks.h" 49 #include "opt_vm.h" 50 51 #include <sys/param.h> 52 #include <sys/systm.h> 53 #include <sys/capsicum.h> 54 #include <sys/kernel.h> 55 #include <sys/lock.h> 56 #include <sys/mutex.h> 57 #include <sys/sysproto.h> 58 #include <sys/filedesc.h> 59 #include <sys/priv.h> 60 #include <sys/proc.h> 61 #include <sys/procctl.h> 62 #include <sys/racct.h> 63 #include <sys/resource.h> 64 #include <sys/resourcevar.h> 65 #include <sys/rwlock.h> 66 #include <sys/sysctl.h> 67 #include <sys/vnode.h> 68 #include <sys/fcntl.h> 69 #include <sys/file.h> 70 #include <sys/mman.h> 71 #include <sys/mount.h> 72 #include <sys/conf.h> 73 #include <sys/stat.h> 74 #include <sys/syscallsubr.h> 75 #include <sys/sysent.h> 76 #include <sys/vmmeter.h> 77 #if defined(__amd64__) || defined(__i386__) /* for i386_read_exec */ 78 #include <machine/md_var.h> 79 #endif 80 81 #include <security/audit/audit.h> 82 #include <security/mac/mac_framework.h> 83 84 #include <vm/vm.h> 85 #include <vm/vm_param.h> 86 #include <vm/pmap.h> 87 #include <vm/vm_map.h> 88 #include <vm/vm_object.h> 89 #include <vm/vm_page.h> 90 #include <vm/vm_pager.h> 91 #include <vm/vm_pageout.h> 92 #include <vm/vm_extern.h> 93 #include <vm/vm_page.h> 94 #include <vm/vnode_pager.h> 95 96 #ifdef HWPMC_HOOKS 97 #include <sys/pmckern.h> 98 #endif 99 100 int old_mlock = 0; 101 SYSCTL_INT(_vm, OID_AUTO, old_mlock, CTLFLAG_RWTUN, &old_mlock, 0, 102 "Do not apply RLIMIT_MEMLOCK on mlockall"); 103 static int mincore_mapped = 1; 104 SYSCTL_INT(_vm, OID_AUTO, mincore_mapped, CTLFLAG_RWTUN, &mincore_mapped, 0, 105 "mincore reports mappings, not residency"); 106 static int imply_prot_max = 0; 107 SYSCTL_INT(_vm, OID_AUTO, imply_prot_max, CTLFLAG_RWTUN, &imply_prot_max, 0, 108 "Imply maximum page permissions in mmap() when none are specified"); 109 110 #ifdef MAP_32BIT 111 #define MAP_32BIT_MAX_ADDR ((vm_offset_t)1 << 31) 112 #endif 113 114 #ifndef _SYS_SYSPROTO_H_ 115 struct sbrk_args { 116 int incr; 117 }; 118 #endif 119 120 int 121 sys_sbrk(struct thread *td, struct sbrk_args *uap) 122 { 123 /* Not yet implemented */ 124 return (EOPNOTSUPP); 125 } 126 127 #ifndef _SYS_SYSPROTO_H_ 128 struct sstk_args { 129 int incr; 130 }; 131 #endif 132 133 int 134 sys_sstk(struct thread *td, struct sstk_args *uap) 135 { 136 /* Not yet implemented */ 137 return (EOPNOTSUPP); 138 } 139 140 #if defined(COMPAT_43) 141 int 142 ogetpagesize(struct thread *td, struct ogetpagesize_args *uap) 143 { 144 145 td->td_retval[0] = PAGE_SIZE; 146 return (0); 147 } 148 #endif /* COMPAT_43 */ 149 150 151 /* 152 * Memory Map (mmap) system call. Note that the file offset 153 * and address are allowed to be NOT page aligned, though if 154 * the MAP_FIXED flag it set, both must have the same remainder 155 * modulo the PAGE_SIZE (POSIX 1003.1b). If the address is not 156 * page-aligned, the actual mapping starts at trunc_page(addr) 157 * and the return value is adjusted up by the page offset. 158 * 159 * Generally speaking, only character devices which are themselves 160 * memory-based, such as a video framebuffer, can be mmap'd. Otherwise 161 * there would be no cache coherency between a descriptor and a VM mapping 162 * both to the same character device. 163 */ 164 #ifndef _SYS_SYSPROTO_H_ 165 struct mmap_args { 166 void *addr; 167 size_t len; 168 int prot; 169 int flags; 170 int fd; 171 long pad; 172 off_t pos; 173 }; 174 #endif 175 176 int 177 sys_mmap(struct thread *td, struct mmap_args *uap) 178 { 179 180 return (kern_mmap(td, (uintptr_t)uap->addr, uap->len, uap->prot, 181 uap->flags, uap->fd, uap->pos)); 182 } 183 184 int 185 kern_mmap(struct thread *td, uintptr_t addr0, size_t len, int prot, int flags, 186 int fd, off_t pos) 187 { 188 struct vmspace *vms; 189 struct file *fp; 190 vm_offset_t addr; 191 vm_size_t pageoff, size; 192 vm_prot_t cap_maxprot; 193 int align, error, max_prot; 194 cap_rights_t rights; 195 196 if ((prot & ~(_PROT_ALL | PROT_MAX(_PROT_ALL))) != 0) 197 return (EINVAL); 198 max_prot = PROT_MAX_EXTRACT(prot); 199 prot = PROT_EXTRACT(prot); 200 if (max_prot != 0 && (max_prot & prot) != prot) 201 return (EINVAL); 202 /* 203 * Always honor PROT_MAX if set. If not, default to all 204 * permissions unless we're implying maximum permissions. 205 * 206 * XXX: should be tunable per process and ABI. 207 */ 208 if (max_prot == 0) 209 max_prot = (imply_prot_max && prot != PROT_NONE) ? 210 prot : _PROT_ALL; 211 212 vms = td->td_proc->p_vmspace; 213 fp = NULL; 214 AUDIT_ARG_FD(fd); 215 addr = addr0; 216 217 /* 218 * Ignore old flags that used to be defined but did not do anything. 219 */ 220 flags &= ~(MAP_RESERVED0020 | MAP_RESERVED0040); 221 222 /* 223 * Enforce the constraints. 224 * Mapping of length 0 is only allowed for old binaries. 225 * Anonymous mapping shall specify -1 as filedescriptor and 226 * zero position for new code. Be nice to ancient a.out 227 * binaries and correct pos for anonymous mapping, since old 228 * ld.so sometimes issues anonymous map requests with non-zero 229 * pos. 230 */ 231 if (!SV_CURPROC_FLAG(SV_AOUT)) { 232 if ((len == 0 && curproc->p_osrel >= P_OSREL_MAP_ANON) || 233 ((flags & MAP_ANON) != 0 && (fd != -1 || pos != 0))) 234 return (EINVAL); 235 } else { 236 if ((flags & MAP_ANON) != 0) 237 pos = 0; 238 } 239 240 if (flags & MAP_STACK) { 241 if ((fd != -1) || 242 ((prot & (PROT_READ | PROT_WRITE)) != (PROT_READ | PROT_WRITE))) 243 return (EINVAL); 244 flags |= MAP_ANON; 245 pos = 0; 246 } 247 if ((flags & ~(MAP_SHARED | MAP_PRIVATE | MAP_FIXED | MAP_HASSEMAPHORE | 248 MAP_STACK | MAP_NOSYNC | MAP_ANON | MAP_EXCL | MAP_NOCORE | 249 MAP_PREFAULT_READ | MAP_GUARD | 250 #ifdef MAP_32BIT 251 MAP_32BIT | 252 #endif 253 MAP_ALIGNMENT_MASK)) != 0) 254 return (EINVAL); 255 if ((flags & (MAP_EXCL | MAP_FIXED)) == MAP_EXCL) 256 return (EINVAL); 257 if ((flags & (MAP_SHARED | MAP_PRIVATE)) == (MAP_SHARED | MAP_PRIVATE)) 258 return (EINVAL); 259 if (prot != PROT_NONE && 260 (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC)) != 0) 261 return (EINVAL); 262 if ((flags & MAP_GUARD) != 0 && (prot != PROT_NONE || fd != -1 || 263 pos != 0 || (flags & ~(MAP_FIXED | MAP_GUARD | MAP_EXCL | 264 #ifdef MAP_32BIT 265 MAP_32BIT | 266 #endif 267 MAP_ALIGNMENT_MASK)) != 0)) 268 return (EINVAL); 269 270 /* 271 * Align the file position to a page boundary, 272 * and save its page offset component. 273 */ 274 pageoff = (pos & PAGE_MASK); 275 pos -= pageoff; 276 277 /* Compute size from len by rounding (on both ends). */ 278 size = len + pageoff; /* low end... */ 279 size = round_page(size); /* hi end */ 280 /* Check for rounding up to zero. */ 281 if (len > size) 282 return (ENOMEM); 283 284 /* Ensure alignment is at least a page and fits in a pointer. */ 285 align = flags & MAP_ALIGNMENT_MASK; 286 if (align != 0 && align != MAP_ALIGNED_SUPER && 287 (align >> MAP_ALIGNMENT_SHIFT >= sizeof(void *) * NBBY || 288 align >> MAP_ALIGNMENT_SHIFT < PAGE_SHIFT)) 289 return (EINVAL); 290 291 /* 292 * Check for illegal addresses. Watch out for address wrap... Note 293 * that VM_*_ADDRESS are not constants due to casts (argh). 294 */ 295 if (flags & MAP_FIXED) { 296 /* 297 * The specified address must have the same remainder 298 * as the file offset taken modulo PAGE_SIZE, so it 299 * should be aligned after adjustment by pageoff. 300 */ 301 addr -= pageoff; 302 if (addr & PAGE_MASK) 303 return (EINVAL); 304 305 /* Address range must be all in user VM space. */ 306 if (addr < vm_map_min(&vms->vm_map) || 307 addr + size > vm_map_max(&vms->vm_map)) 308 return (EINVAL); 309 if (addr + size < addr) 310 return (EINVAL); 311 #ifdef MAP_32BIT 312 if (flags & MAP_32BIT && addr + size > MAP_32BIT_MAX_ADDR) 313 return (EINVAL); 314 } else if (flags & MAP_32BIT) { 315 /* 316 * For MAP_32BIT, override the hint if it is too high and 317 * do not bother moving the mapping past the heap (since 318 * the heap is usually above 2GB). 319 */ 320 if (addr + size > MAP_32BIT_MAX_ADDR) 321 addr = 0; 322 #endif 323 } else { 324 /* 325 * XXX for non-fixed mappings where no hint is provided or 326 * the hint would fall in the potential heap space, 327 * place it after the end of the largest possible heap. 328 * 329 * There should really be a pmap call to determine a reasonable 330 * location. 331 */ 332 if (addr == 0 || 333 (addr >= round_page((vm_offset_t)vms->vm_taddr) && 334 addr < round_page((vm_offset_t)vms->vm_daddr + 335 lim_max(td, RLIMIT_DATA)))) 336 addr = round_page((vm_offset_t)vms->vm_daddr + 337 lim_max(td, RLIMIT_DATA)); 338 } 339 if (len == 0) { 340 /* 341 * Return success without mapping anything for old 342 * binaries that request a page-aligned mapping of 343 * length 0. For modern binaries, this function 344 * returns an error earlier. 345 */ 346 error = 0; 347 } else if ((flags & MAP_GUARD) != 0) { 348 error = vm_mmap_object(&vms->vm_map, &addr, size, VM_PROT_NONE, 349 VM_PROT_NONE, flags, NULL, pos, FALSE, td); 350 } else if ((flags & MAP_ANON) != 0) { 351 /* 352 * Mapping blank space is trivial. 353 * 354 * This relies on VM_PROT_* matching PROT_*. 355 */ 356 error = vm_mmap_object(&vms->vm_map, &addr, size, prot, 357 max_prot, flags, NULL, pos, FALSE, td); 358 } else { 359 /* 360 * Mapping file, get fp for validation and don't let the 361 * descriptor disappear on us if we block. Check capability 362 * rights, but also return the maximum rights to be combined 363 * with maxprot later. 364 */ 365 cap_rights_init(&rights, CAP_MMAP); 366 if (prot & PROT_READ) 367 cap_rights_set(&rights, CAP_MMAP_R); 368 if ((flags & MAP_SHARED) != 0) { 369 if (prot & PROT_WRITE) 370 cap_rights_set(&rights, CAP_MMAP_W); 371 } 372 if (prot & PROT_EXEC) 373 cap_rights_set(&rights, CAP_MMAP_X); 374 error = fget_mmap(td, fd, &rights, &cap_maxprot, &fp); 375 if (error != 0) 376 goto done; 377 if ((flags & (MAP_SHARED | MAP_PRIVATE)) == 0 && 378 td->td_proc->p_osrel >= P_OSREL_MAP_FSTRICT) { 379 error = EINVAL; 380 goto done; 381 } 382 383 /* This relies on VM_PROT_* matching PROT_*. */ 384 error = fo_mmap(fp, &vms->vm_map, &addr, size, prot, 385 max_prot & cap_maxprot, flags, pos, td); 386 } 387 388 if (error == 0) 389 td->td_retval[0] = (register_t) (addr + pageoff); 390 done: 391 if (fp) 392 fdrop(fp, td); 393 394 return (error); 395 } 396 397 #if defined(COMPAT_FREEBSD6) 398 int 399 freebsd6_mmap(struct thread *td, struct freebsd6_mmap_args *uap) 400 { 401 402 return (kern_mmap(td, (uintptr_t)uap->addr, uap->len, uap->prot, 403 uap->flags, uap->fd, uap->pos)); 404 } 405 #endif 406 407 #ifdef COMPAT_43 408 #ifndef _SYS_SYSPROTO_H_ 409 struct ommap_args { 410 caddr_t addr; 411 int len; 412 int prot; 413 int flags; 414 int fd; 415 long pos; 416 }; 417 #endif 418 int 419 ommap(struct thread *td, struct ommap_args *uap) 420 { 421 static const char cvtbsdprot[8] = { 422 0, 423 PROT_EXEC, 424 PROT_WRITE, 425 PROT_EXEC | PROT_WRITE, 426 PROT_READ, 427 PROT_EXEC | PROT_READ, 428 PROT_WRITE | PROT_READ, 429 PROT_EXEC | PROT_WRITE | PROT_READ, 430 }; 431 int flags, prot; 432 433 #define OMAP_ANON 0x0002 434 #define OMAP_COPY 0x0020 435 #define OMAP_SHARED 0x0010 436 #define OMAP_FIXED 0x0100 437 438 prot = cvtbsdprot[uap->prot & 0x7]; 439 #if (defined(COMPAT_FREEBSD32) && defined(__amd64__)) || defined(__i386__) 440 if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32) && 441 prot != 0) 442 prot |= PROT_EXEC; 443 #endif 444 flags = 0; 445 if (uap->flags & OMAP_ANON) 446 flags |= MAP_ANON; 447 if (uap->flags & OMAP_COPY) 448 flags |= MAP_COPY; 449 if (uap->flags & OMAP_SHARED) 450 flags |= MAP_SHARED; 451 else 452 flags |= MAP_PRIVATE; 453 if (uap->flags & OMAP_FIXED) 454 flags |= MAP_FIXED; 455 return (kern_mmap(td, (uintptr_t)uap->addr, uap->len, prot, flags, 456 uap->fd, uap->pos)); 457 } 458 #endif /* COMPAT_43 */ 459 460 461 #ifndef _SYS_SYSPROTO_H_ 462 struct msync_args { 463 void *addr; 464 size_t len; 465 int flags; 466 }; 467 #endif 468 int 469 sys_msync(struct thread *td, struct msync_args *uap) 470 { 471 472 return (kern_msync(td, (uintptr_t)uap->addr, uap->len, uap->flags)); 473 } 474 475 int 476 kern_msync(struct thread *td, uintptr_t addr0, size_t size, int flags) 477 { 478 vm_offset_t addr; 479 vm_size_t pageoff; 480 vm_map_t map; 481 int rv; 482 483 addr = addr0; 484 pageoff = (addr & PAGE_MASK); 485 addr -= pageoff; 486 size += pageoff; 487 size = (vm_size_t) round_page(size); 488 if (addr + size < addr) 489 return (EINVAL); 490 491 if ((flags & (MS_ASYNC|MS_INVALIDATE)) == (MS_ASYNC|MS_INVALIDATE)) 492 return (EINVAL); 493 494 map = &td->td_proc->p_vmspace->vm_map; 495 496 /* 497 * Clean the pages and interpret the return value. 498 */ 499 rv = vm_map_sync(map, addr, addr + size, (flags & MS_ASYNC) == 0, 500 (flags & MS_INVALIDATE) != 0); 501 switch (rv) { 502 case KERN_SUCCESS: 503 return (0); 504 case KERN_INVALID_ADDRESS: 505 return (ENOMEM); 506 case KERN_INVALID_ARGUMENT: 507 return (EBUSY); 508 case KERN_FAILURE: 509 return (EIO); 510 default: 511 return (EINVAL); 512 } 513 } 514 515 #ifndef _SYS_SYSPROTO_H_ 516 struct munmap_args { 517 void *addr; 518 size_t len; 519 }; 520 #endif 521 int 522 sys_munmap(struct thread *td, struct munmap_args *uap) 523 { 524 525 return (kern_munmap(td, (uintptr_t)uap->addr, uap->len)); 526 } 527 528 int 529 kern_munmap(struct thread *td, uintptr_t addr0, size_t size) 530 { 531 #ifdef HWPMC_HOOKS 532 struct pmckern_map_out pkm; 533 vm_map_entry_t entry; 534 bool pmc_handled; 535 #endif 536 vm_offset_t addr; 537 vm_size_t pageoff; 538 vm_map_t map; 539 540 if (size == 0) 541 return (EINVAL); 542 543 addr = addr0; 544 pageoff = (addr & PAGE_MASK); 545 addr -= pageoff; 546 size += pageoff; 547 size = (vm_size_t) round_page(size); 548 if (addr + size < addr) 549 return (EINVAL); 550 551 /* 552 * Check for illegal addresses. Watch out for address wrap... 553 */ 554 map = &td->td_proc->p_vmspace->vm_map; 555 if (addr < vm_map_min(map) || addr + size > vm_map_max(map)) 556 return (EINVAL); 557 vm_map_lock(map); 558 #ifdef HWPMC_HOOKS 559 pmc_handled = false; 560 if (PMC_HOOK_INSTALLED(PMC_FN_MUNMAP)) { 561 pmc_handled = true; 562 /* 563 * Inform hwpmc if the address range being unmapped contains 564 * an executable region. 565 */ 566 pkm.pm_address = (uintptr_t) NULL; 567 if (vm_map_lookup_entry(map, addr, &entry)) { 568 for (; entry->start < addr + size; 569 entry = entry->next) { 570 if (vm_map_check_protection(map, entry->start, 571 entry->end, VM_PROT_EXECUTE) == TRUE) { 572 pkm.pm_address = (uintptr_t) addr; 573 pkm.pm_size = (size_t) size; 574 break; 575 } 576 } 577 } 578 } 579 #endif 580 vm_map_delete(map, addr, addr + size); 581 582 #ifdef HWPMC_HOOKS 583 if (__predict_false(pmc_handled)) { 584 /* downgrade the lock to prevent a LOR with the pmc-sx lock */ 585 vm_map_lock_downgrade(map); 586 if (pkm.pm_address != (uintptr_t) NULL) 587 PMC_CALL_HOOK(td, PMC_FN_MUNMAP, (void *) &pkm); 588 vm_map_unlock_read(map); 589 } else 590 #endif 591 vm_map_unlock(map); 592 593 /* vm_map_delete returns nothing but KERN_SUCCESS anyway */ 594 return (0); 595 } 596 597 #ifndef _SYS_SYSPROTO_H_ 598 struct mprotect_args { 599 const void *addr; 600 size_t len; 601 int prot; 602 }; 603 #endif 604 int 605 sys_mprotect(struct thread *td, struct mprotect_args *uap) 606 { 607 608 return (kern_mprotect(td, (uintptr_t)uap->addr, uap->len, uap->prot)); 609 } 610 611 int 612 kern_mprotect(struct thread *td, uintptr_t addr0, size_t size, int prot) 613 { 614 vm_offset_t addr; 615 vm_size_t pageoff; 616 int vm_error, max_prot; 617 618 addr = addr0; 619 if ((prot & ~(_PROT_ALL | PROT_MAX(_PROT_ALL))) != 0) 620 return (EINVAL); 621 max_prot = PROT_MAX_EXTRACT(prot); 622 prot = PROT_EXTRACT(prot); 623 pageoff = (addr & PAGE_MASK); 624 addr -= pageoff; 625 size += pageoff; 626 size = (vm_size_t) round_page(size); 627 #ifdef COMPAT_FREEBSD32 628 if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) { 629 if (((addr + size) & 0xffffffff) < addr) 630 return (EINVAL); 631 } else 632 #endif 633 if (addr + size < addr) 634 return (EINVAL); 635 636 vm_error = KERN_SUCCESS; 637 if (max_prot != 0) { 638 if ((max_prot & prot) != prot) 639 return (EINVAL); 640 vm_error = vm_map_protect(&td->td_proc->p_vmspace->vm_map, 641 addr, addr + size, max_prot, TRUE); 642 } 643 if (vm_error == KERN_SUCCESS) 644 vm_error = vm_map_protect(&td->td_proc->p_vmspace->vm_map, 645 addr, addr + size, prot, FALSE); 646 647 switch (vm_error) { 648 case KERN_SUCCESS: 649 return (0); 650 case KERN_PROTECTION_FAILURE: 651 return (EACCES); 652 case KERN_RESOURCE_SHORTAGE: 653 return (ENOMEM); 654 } 655 return (EINVAL); 656 } 657 658 #ifndef _SYS_SYSPROTO_H_ 659 struct minherit_args { 660 void *addr; 661 size_t len; 662 int inherit; 663 }; 664 #endif 665 int 666 sys_minherit(struct thread *td, struct minherit_args *uap) 667 { 668 vm_offset_t addr; 669 vm_size_t size, pageoff; 670 vm_inherit_t inherit; 671 672 addr = (vm_offset_t)uap->addr; 673 size = uap->len; 674 inherit = uap->inherit; 675 676 pageoff = (addr & PAGE_MASK); 677 addr -= pageoff; 678 size += pageoff; 679 size = (vm_size_t) round_page(size); 680 if (addr + size < addr) 681 return (EINVAL); 682 683 switch (vm_map_inherit(&td->td_proc->p_vmspace->vm_map, addr, 684 addr + size, inherit)) { 685 case KERN_SUCCESS: 686 return (0); 687 case KERN_PROTECTION_FAILURE: 688 return (EACCES); 689 } 690 return (EINVAL); 691 } 692 693 #ifndef _SYS_SYSPROTO_H_ 694 struct madvise_args { 695 void *addr; 696 size_t len; 697 int behav; 698 }; 699 #endif 700 701 int 702 sys_madvise(struct thread *td, struct madvise_args *uap) 703 { 704 705 return (kern_madvise(td, (uintptr_t)uap->addr, uap->len, uap->behav)); 706 } 707 708 int 709 kern_madvise(struct thread *td, uintptr_t addr0, size_t len, int behav) 710 { 711 vm_map_t map; 712 vm_offset_t addr, end, start; 713 int flags; 714 715 /* 716 * Check for our special case, advising the swap pager we are 717 * "immortal." 718 */ 719 if (behav == MADV_PROTECT) { 720 flags = PPROT_SET; 721 return (kern_procctl(td, P_PID, td->td_proc->p_pid, 722 PROC_SPROTECT, &flags)); 723 } 724 725 /* 726 * Check for illegal addresses. Watch out for address wrap... Note 727 * that VM_*_ADDRESS are not constants due to casts (argh). 728 */ 729 map = &td->td_proc->p_vmspace->vm_map; 730 addr = addr0; 731 if (addr < vm_map_min(map) || addr + len > vm_map_max(map)) 732 return (EINVAL); 733 if ((addr + len) < addr) 734 return (EINVAL); 735 736 /* 737 * Since this routine is only advisory, we default to conservative 738 * behavior. 739 */ 740 start = trunc_page(addr); 741 end = round_page(addr + len); 742 743 /* 744 * vm_map_madvise() checks for illegal values of behav. 745 */ 746 return (vm_map_madvise(map, start, end, behav)); 747 } 748 749 #ifndef _SYS_SYSPROTO_H_ 750 struct mincore_args { 751 const void *addr; 752 size_t len; 753 char *vec; 754 }; 755 #endif 756 757 int 758 sys_mincore(struct thread *td, struct mincore_args *uap) 759 { 760 761 return (kern_mincore(td, (uintptr_t)uap->addr, uap->len, uap->vec)); 762 } 763 764 int 765 kern_mincore(struct thread *td, uintptr_t addr0, size_t len, char *vec) 766 { 767 vm_offset_t addr, first_addr; 768 vm_offset_t end, cend; 769 pmap_t pmap; 770 vm_map_t map; 771 int error = 0; 772 int vecindex, lastvecindex; 773 vm_map_entry_t current; 774 vm_map_entry_t entry; 775 vm_object_t object; 776 vm_paddr_t locked_pa; 777 vm_page_t m; 778 vm_pindex_t pindex; 779 int mincoreinfo; 780 unsigned int timestamp; 781 boolean_t locked; 782 783 /* 784 * Make sure that the addresses presented are valid for user 785 * mode. 786 */ 787 first_addr = addr = trunc_page(addr0); 788 end = addr + (vm_size_t)round_page(len); 789 map = &td->td_proc->p_vmspace->vm_map; 790 if (end > vm_map_max(map) || end < addr) 791 return (ENOMEM); 792 793 pmap = vmspace_pmap(td->td_proc->p_vmspace); 794 795 vm_map_lock_read(map); 796 RestartScan: 797 timestamp = map->timestamp; 798 799 if (!vm_map_lookup_entry(map, addr, &entry)) { 800 vm_map_unlock_read(map); 801 return (ENOMEM); 802 } 803 804 /* 805 * Do this on a map entry basis so that if the pages are not 806 * in the current processes address space, we can easily look 807 * up the pages elsewhere. 808 */ 809 lastvecindex = -1; 810 for (current = entry; current->start < end; current = current->next) { 811 812 /* 813 * check for contiguity 814 */ 815 if (current->end < end && current->next->start > current->end) { 816 vm_map_unlock_read(map); 817 return (ENOMEM); 818 } 819 820 /* 821 * ignore submaps (for now) or null objects 822 */ 823 if ((current->eflags & MAP_ENTRY_IS_SUB_MAP) || 824 current->object.vm_object == NULL) 825 continue; 826 827 /* 828 * limit this scan to the current map entry and the 829 * limits for the mincore call 830 */ 831 if (addr < current->start) 832 addr = current->start; 833 cend = current->end; 834 if (cend > end) 835 cend = end; 836 837 /* 838 * scan this entry one page at a time 839 */ 840 while (addr < cend) { 841 /* 842 * Check pmap first, it is likely faster, also 843 * it can provide info as to whether we are the 844 * one referencing or modifying the page. 845 */ 846 object = NULL; 847 locked_pa = 0; 848 retry: 849 m = NULL; 850 mincoreinfo = pmap_mincore(pmap, addr, &locked_pa); 851 if (mincore_mapped) { 852 /* 853 * We only care about this pmap's 854 * mapping of the page, if any. 855 */ 856 if (locked_pa != 0) { 857 vm_page_unlock(PHYS_TO_VM_PAGE( 858 locked_pa)); 859 } 860 } else if (locked_pa != 0) { 861 /* 862 * The page is mapped by this process but not 863 * both accessed and modified. It is also 864 * managed. Acquire the object lock so that 865 * other mappings might be examined. 866 */ 867 m = PHYS_TO_VM_PAGE(locked_pa); 868 if (m->object != object) { 869 if (object != NULL) 870 VM_OBJECT_WUNLOCK(object); 871 object = m->object; 872 locked = VM_OBJECT_TRYWLOCK(object); 873 vm_page_unlock(m); 874 if (!locked) { 875 VM_OBJECT_WLOCK(object); 876 vm_page_lock(m); 877 goto retry; 878 } 879 } else 880 vm_page_unlock(m); 881 KASSERT(m->valid == VM_PAGE_BITS_ALL, 882 ("mincore: page %p is mapped but invalid", 883 m)); 884 } else if (mincoreinfo == 0) { 885 /* 886 * The page is not mapped by this process. If 887 * the object implements managed pages, then 888 * determine if the page is resident so that 889 * the mappings might be examined. 890 */ 891 if (current->object.vm_object != object) { 892 if (object != NULL) 893 VM_OBJECT_WUNLOCK(object); 894 object = current->object.vm_object; 895 VM_OBJECT_WLOCK(object); 896 } 897 if (object->type == OBJT_DEFAULT || 898 object->type == OBJT_SWAP || 899 object->type == OBJT_VNODE) { 900 pindex = OFF_TO_IDX(current->offset + 901 (addr - current->start)); 902 m = vm_page_lookup(object, pindex); 903 if (m != NULL && m->valid == 0) 904 m = NULL; 905 if (m != NULL) 906 mincoreinfo = MINCORE_INCORE; 907 } 908 } 909 if (m != NULL) { 910 /* Examine other mappings to the page. */ 911 if (m->dirty == 0 && pmap_is_modified(m)) 912 vm_page_dirty(m); 913 if (m->dirty != 0) 914 mincoreinfo |= MINCORE_MODIFIED_OTHER; 915 /* 916 * The first test for PGA_REFERENCED is an 917 * optimization. The second test is 918 * required because a concurrent pmap 919 * operation could clear the last reference 920 * and set PGA_REFERENCED before the call to 921 * pmap_is_referenced(). 922 */ 923 if ((m->aflags & PGA_REFERENCED) != 0 || 924 pmap_is_referenced(m) || 925 (m->aflags & PGA_REFERENCED) != 0) 926 mincoreinfo |= MINCORE_REFERENCED_OTHER; 927 } 928 if (object != NULL) 929 VM_OBJECT_WUNLOCK(object); 930 931 /* 932 * subyte may page fault. In case it needs to modify 933 * the map, we release the lock. 934 */ 935 vm_map_unlock_read(map); 936 937 /* 938 * calculate index into user supplied byte vector 939 */ 940 vecindex = atop(addr - first_addr); 941 942 /* 943 * If we have skipped map entries, we need to make sure that 944 * the byte vector is zeroed for those skipped entries. 945 */ 946 while ((lastvecindex + 1) < vecindex) { 947 ++lastvecindex; 948 error = subyte(vec + lastvecindex, 0); 949 if (error) { 950 error = EFAULT; 951 goto done2; 952 } 953 } 954 955 /* 956 * Pass the page information to the user 957 */ 958 error = subyte(vec + vecindex, mincoreinfo); 959 if (error) { 960 error = EFAULT; 961 goto done2; 962 } 963 964 /* 965 * If the map has changed, due to the subyte, the previous 966 * output may be invalid. 967 */ 968 vm_map_lock_read(map); 969 if (timestamp != map->timestamp) 970 goto RestartScan; 971 972 lastvecindex = vecindex; 973 addr += PAGE_SIZE; 974 } 975 } 976 977 /* 978 * subyte may page fault. In case it needs to modify 979 * the map, we release the lock. 980 */ 981 vm_map_unlock_read(map); 982 983 /* 984 * Zero the last entries in the byte vector. 985 */ 986 vecindex = atop(end - first_addr); 987 while ((lastvecindex + 1) < vecindex) { 988 ++lastvecindex; 989 error = subyte(vec + lastvecindex, 0); 990 if (error) { 991 error = EFAULT; 992 goto done2; 993 } 994 } 995 996 /* 997 * If the map has changed, due to the subyte, the previous 998 * output may be invalid. 999 */ 1000 vm_map_lock_read(map); 1001 if (timestamp != map->timestamp) 1002 goto RestartScan; 1003 vm_map_unlock_read(map); 1004 done2: 1005 return (error); 1006 } 1007 1008 #ifndef _SYS_SYSPROTO_H_ 1009 struct mlock_args { 1010 const void *addr; 1011 size_t len; 1012 }; 1013 #endif 1014 int 1015 sys_mlock(struct thread *td, struct mlock_args *uap) 1016 { 1017 1018 return (kern_mlock(td->td_proc, td->td_ucred, 1019 __DECONST(uintptr_t, uap->addr), uap->len)); 1020 } 1021 1022 int 1023 kern_mlock(struct proc *proc, struct ucred *cred, uintptr_t addr0, size_t len) 1024 { 1025 vm_offset_t addr, end, last, start; 1026 vm_size_t npages, size; 1027 vm_map_t map; 1028 unsigned long nsize; 1029 int error; 1030 1031 error = priv_check_cred(cred, PRIV_VM_MLOCK); 1032 if (error) 1033 return (error); 1034 addr = addr0; 1035 size = len; 1036 last = addr + size; 1037 start = trunc_page(addr); 1038 end = round_page(last); 1039 if (last < addr || end < addr) 1040 return (EINVAL); 1041 npages = atop(end - start); 1042 if (npages > vm_page_max_user_wired) 1043 return (ENOMEM); 1044 map = &proc->p_vmspace->vm_map; 1045 PROC_LOCK(proc); 1046 nsize = ptoa(npages + pmap_wired_count(map->pmap)); 1047 if (nsize > lim_cur_proc(proc, RLIMIT_MEMLOCK)) { 1048 PROC_UNLOCK(proc); 1049 return (ENOMEM); 1050 } 1051 PROC_UNLOCK(proc); 1052 #ifdef RACCT 1053 if (racct_enable) { 1054 PROC_LOCK(proc); 1055 error = racct_set(proc, RACCT_MEMLOCK, nsize); 1056 PROC_UNLOCK(proc); 1057 if (error != 0) 1058 return (ENOMEM); 1059 } 1060 #endif 1061 error = vm_map_wire(map, start, end, 1062 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); 1063 #ifdef RACCT 1064 if (racct_enable && error != KERN_SUCCESS) { 1065 PROC_LOCK(proc); 1066 racct_set(proc, RACCT_MEMLOCK, 1067 ptoa(pmap_wired_count(map->pmap))); 1068 PROC_UNLOCK(proc); 1069 } 1070 #endif 1071 return (error == KERN_SUCCESS ? 0 : ENOMEM); 1072 } 1073 1074 #ifndef _SYS_SYSPROTO_H_ 1075 struct mlockall_args { 1076 int how; 1077 }; 1078 #endif 1079 1080 int 1081 sys_mlockall(struct thread *td, struct mlockall_args *uap) 1082 { 1083 vm_map_t map; 1084 int error; 1085 1086 map = &td->td_proc->p_vmspace->vm_map; 1087 error = priv_check(td, PRIV_VM_MLOCK); 1088 if (error) 1089 return (error); 1090 1091 if ((uap->how == 0) || ((uap->how & ~(MCL_CURRENT|MCL_FUTURE)) != 0)) 1092 return (EINVAL); 1093 1094 /* 1095 * If wiring all pages in the process would cause it to exceed 1096 * a hard resource limit, return ENOMEM. 1097 */ 1098 if (!old_mlock && uap->how & MCL_CURRENT) { 1099 if (map->size > lim_cur(td, RLIMIT_MEMLOCK)) 1100 return (ENOMEM); 1101 } 1102 #ifdef RACCT 1103 if (racct_enable) { 1104 PROC_LOCK(td->td_proc); 1105 error = racct_set(td->td_proc, RACCT_MEMLOCK, map->size); 1106 PROC_UNLOCK(td->td_proc); 1107 if (error != 0) 1108 return (ENOMEM); 1109 } 1110 #endif 1111 1112 if (uap->how & MCL_FUTURE) { 1113 vm_map_lock(map); 1114 vm_map_modflags(map, MAP_WIREFUTURE, 0); 1115 vm_map_unlock(map); 1116 error = 0; 1117 } 1118 1119 if (uap->how & MCL_CURRENT) { 1120 /* 1121 * P1003.1-2001 mandates that all currently mapped pages 1122 * will be memory resident and locked (wired) upon return 1123 * from mlockall(). vm_map_wire() will wire pages, by 1124 * calling vm_fault_wire() for each page in the region. 1125 */ 1126 error = vm_map_wire(map, vm_map_min(map), vm_map_max(map), 1127 VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); 1128 if (error == KERN_SUCCESS) 1129 error = 0; 1130 else if (error == KERN_RESOURCE_SHORTAGE) 1131 error = ENOMEM; 1132 else 1133 error = EAGAIN; 1134 } 1135 #ifdef RACCT 1136 if (racct_enable && error != KERN_SUCCESS) { 1137 PROC_LOCK(td->td_proc); 1138 racct_set(td->td_proc, RACCT_MEMLOCK, 1139 ptoa(pmap_wired_count(map->pmap))); 1140 PROC_UNLOCK(td->td_proc); 1141 } 1142 #endif 1143 1144 return (error); 1145 } 1146 1147 #ifndef _SYS_SYSPROTO_H_ 1148 struct munlockall_args { 1149 register_t dummy; 1150 }; 1151 #endif 1152 1153 int 1154 sys_munlockall(struct thread *td, struct munlockall_args *uap) 1155 { 1156 vm_map_t map; 1157 int error; 1158 1159 map = &td->td_proc->p_vmspace->vm_map; 1160 error = priv_check(td, PRIV_VM_MUNLOCK); 1161 if (error) 1162 return (error); 1163 1164 /* Clear the MAP_WIREFUTURE flag from this vm_map. */ 1165 vm_map_lock(map); 1166 vm_map_modflags(map, 0, MAP_WIREFUTURE); 1167 vm_map_unlock(map); 1168 1169 /* Forcibly unwire all pages. */ 1170 error = vm_map_unwire(map, vm_map_min(map), vm_map_max(map), 1171 VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); 1172 #ifdef RACCT 1173 if (racct_enable && error == KERN_SUCCESS) { 1174 PROC_LOCK(td->td_proc); 1175 racct_set(td->td_proc, RACCT_MEMLOCK, 0); 1176 PROC_UNLOCK(td->td_proc); 1177 } 1178 #endif 1179 1180 return (error); 1181 } 1182 1183 #ifndef _SYS_SYSPROTO_H_ 1184 struct munlock_args { 1185 const void *addr; 1186 size_t len; 1187 }; 1188 #endif 1189 int 1190 sys_munlock(struct thread *td, struct munlock_args *uap) 1191 { 1192 1193 return (kern_munlock(td, (uintptr_t)uap->addr, uap->len)); 1194 } 1195 1196 int 1197 kern_munlock(struct thread *td, uintptr_t addr0, size_t size) 1198 { 1199 vm_offset_t addr, end, last, start; 1200 #ifdef RACCT 1201 vm_map_t map; 1202 #endif 1203 int error; 1204 1205 error = priv_check(td, PRIV_VM_MUNLOCK); 1206 if (error) 1207 return (error); 1208 addr = addr0; 1209 last = addr + size; 1210 start = trunc_page(addr); 1211 end = round_page(last); 1212 if (last < addr || end < addr) 1213 return (EINVAL); 1214 error = vm_map_unwire(&td->td_proc->p_vmspace->vm_map, start, end, 1215 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); 1216 #ifdef RACCT 1217 if (racct_enable && error == KERN_SUCCESS) { 1218 PROC_LOCK(td->td_proc); 1219 map = &td->td_proc->p_vmspace->vm_map; 1220 racct_set(td->td_proc, RACCT_MEMLOCK, 1221 ptoa(pmap_wired_count(map->pmap))); 1222 PROC_UNLOCK(td->td_proc); 1223 } 1224 #endif 1225 return (error == KERN_SUCCESS ? 0 : ENOMEM); 1226 } 1227 1228 /* 1229 * vm_mmap_vnode() 1230 * 1231 * Helper function for vm_mmap. Perform sanity check specific for mmap 1232 * operations on vnodes. 1233 */ 1234 int 1235 vm_mmap_vnode(struct thread *td, vm_size_t objsize, 1236 vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, 1237 struct vnode *vp, vm_ooffset_t *foffp, vm_object_t *objp, 1238 boolean_t *writecounted) 1239 { 1240 struct vattr va; 1241 vm_object_t obj; 1242 vm_ooffset_t foff; 1243 struct ucred *cred; 1244 int error, flags; 1245 bool writex; 1246 1247 cred = td->td_ucred; 1248 writex = (*maxprotp & VM_PROT_WRITE) != 0 && 1249 (*flagsp & MAP_SHARED) != 0; 1250 if ((error = vget(vp, LK_SHARED, td)) != 0) 1251 return (error); 1252 AUDIT_ARG_VNODE1(vp); 1253 foff = *foffp; 1254 flags = *flagsp; 1255 obj = vp->v_object; 1256 if (vp->v_type == VREG) { 1257 /* 1258 * Get the proper underlying object 1259 */ 1260 if (obj == NULL) { 1261 error = EINVAL; 1262 goto done; 1263 } 1264 if (obj->type == OBJT_VNODE && obj->handle != vp) { 1265 vput(vp); 1266 vp = (struct vnode *)obj->handle; 1267 /* 1268 * Bypass filesystems obey the mpsafety of the 1269 * underlying fs. Tmpfs never bypasses. 1270 */ 1271 error = vget(vp, LK_SHARED, td); 1272 if (error != 0) 1273 return (error); 1274 } 1275 if (writex) { 1276 *writecounted = TRUE; 1277 vnode_pager_update_writecount(obj, 0, objsize); 1278 } 1279 } else { 1280 error = EINVAL; 1281 goto done; 1282 } 1283 if ((error = VOP_GETATTR(vp, &va, cred))) 1284 goto done; 1285 #ifdef MAC 1286 /* This relies on VM_PROT_* matching PROT_*. */ 1287 error = mac_vnode_check_mmap(cred, vp, (int)prot, flags); 1288 if (error != 0) 1289 goto done; 1290 #endif 1291 if ((flags & MAP_SHARED) != 0) { 1292 if ((va.va_flags & (SF_SNAPSHOT|IMMUTABLE|APPEND)) != 0) { 1293 if (prot & VM_PROT_WRITE) { 1294 error = EPERM; 1295 goto done; 1296 } 1297 *maxprotp &= ~VM_PROT_WRITE; 1298 } 1299 } 1300 /* 1301 * If it is a regular file without any references 1302 * we do not need to sync it. 1303 * Adjust object size to be the size of actual file. 1304 */ 1305 objsize = round_page(va.va_size); 1306 if (va.va_nlink == 0) 1307 flags |= MAP_NOSYNC; 1308 if (obj->type == OBJT_VNODE) { 1309 obj = vm_pager_allocate(OBJT_VNODE, vp, objsize, prot, foff, 1310 cred); 1311 if (obj == NULL) { 1312 error = ENOMEM; 1313 goto done; 1314 } 1315 } else { 1316 KASSERT(obj->type == OBJT_DEFAULT || obj->type == OBJT_SWAP, 1317 ("wrong object type")); 1318 VM_OBJECT_WLOCK(obj); 1319 vm_object_reference_locked(obj); 1320 #if VM_NRESERVLEVEL > 0 1321 vm_object_color(obj, 0); 1322 #endif 1323 VM_OBJECT_WUNLOCK(obj); 1324 } 1325 *objp = obj; 1326 *flagsp = flags; 1327 1328 vfs_mark_atime(vp, cred); 1329 1330 done: 1331 if (error != 0 && *writecounted) { 1332 *writecounted = FALSE; 1333 vnode_pager_update_writecount(obj, objsize, 0); 1334 } 1335 vput(vp); 1336 return (error); 1337 } 1338 1339 /* 1340 * vm_mmap_cdev() 1341 * 1342 * Helper function for vm_mmap. Perform sanity check specific for mmap 1343 * operations on cdevs. 1344 */ 1345 int 1346 vm_mmap_cdev(struct thread *td, vm_size_t objsize, vm_prot_t prot, 1347 vm_prot_t *maxprotp, int *flagsp, struct cdev *cdev, struct cdevsw *dsw, 1348 vm_ooffset_t *foff, vm_object_t *objp) 1349 { 1350 vm_object_t obj; 1351 int error, flags; 1352 1353 flags = *flagsp; 1354 1355 if (dsw->d_flags & D_MMAP_ANON) { 1356 *objp = NULL; 1357 *foff = 0; 1358 *maxprotp = VM_PROT_ALL; 1359 *flagsp |= MAP_ANON; 1360 return (0); 1361 } 1362 /* 1363 * cdevs do not provide private mappings of any kind. 1364 */ 1365 if ((*maxprotp & VM_PROT_WRITE) == 0 && 1366 (prot & VM_PROT_WRITE) != 0) 1367 return (EACCES); 1368 if (flags & (MAP_PRIVATE|MAP_COPY)) 1369 return (EINVAL); 1370 /* 1371 * Force device mappings to be shared. 1372 */ 1373 flags |= MAP_SHARED; 1374 #ifdef MAC_XXX 1375 error = mac_cdev_check_mmap(td->td_ucred, cdev, (int)prot); 1376 if (error != 0) 1377 return (error); 1378 #endif 1379 /* 1380 * First, try d_mmap_single(). If that is not implemented 1381 * (returns ENODEV), fall back to using the device pager. 1382 * Note that d_mmap_single() must return a reference to the 1383 * object (it needs to bump the reference count of the object 1384 * it returns somehow). 1385 * 1386 * XXX assumes VM_PROT_* == PROT_* 1387 */ 1388 error = dsw->d_mmap_single(cdev, foff, objsize, objp, (int)prot); 1389 if (error != ENODEV) 1390 return (error); 1391 obj = vm_pager_allocate(OBJT_DEVICE, cdev, objsize, prot, *foff, 1392 td->td_ucred); 1393 if (obj == NULL) 1394 return (EINVAL); 1395 *objp = obj; 1396 *flagsp = flags; 1397 return (0); 1398 } 1399 1400 /* 1401 * vm_mmap() 1402 * 1403 * Internal version of mmap used by exec, sys5 shared memory, and 1404 * various device drivers. Handle is either a vnode pointer, a 1405 * character device, or NULL for MAP_ANON. 1406 */ 1407 int 1408 vm_mmap(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, 1409 vm_prot_t maxprot, int flags, 1410 objtype_t handle_type, void *handle, 1411 vm_ooffset_t foff) 1412 { 1413 vm_object_t object; 1414 struct thread *td = curthread; 1415 int error; 1416 boolean_t writecounted; 1417 1418 if (size == 0) 1419 return (EINVAL); 1420 1421 size = round_page(size); 1422 object = NULL; 1423 writecounted = FALSE; 1424 1425 /* 1426 * Lookup/allocate object. 1427 */ 1428 switch (handle_type) { 1429 case OBJT_DEVICE: { 1430 struct cdevsw *dsw; 1431 struct cdev *cdev; 1432 int ref; 1433 1434 cdev = handle; 1435 dsw = dev_refthread(cdev, &ref); 1436 if (dsw == NULL) 1437 return (ENXIO); 1438 error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, cdev, 1439 dsw, &foff, &object); 1440 dev_relthread(cdev, ref); 1441 break; 1442 } 1443 case OBJT_VNODE: 1444 error = vm_mmap_vnode(td, size, prot, &maxprot, &flags, 1445 handle, &foff, &object, &writecounted); 1446 break; 1447 case OBJT_DEFAULT: 1448 if (handle == NULL) { 1449 error = 0; 1450 break; 1451 } 1452 /* FALLTHROUGH */ 1453 default: 1454 error = EINVAL; 1455 break; 1456 } 1457 if (error) 1458 return (error); 1459 1460 error = vm_mmap_object(map, addr, size, prot, maxprot, flags, object, 1461 foff, writecounted, td); 1462 if (error != 0 && object != NULL) { 1463 /* 1464 * If this mapping was accounted for in the vnode's 1465 * writecount, then undo that now. 1466 */ 1467 if (writecounted) 1468 vnode_pager_release_writecount(object, 0, size); 1469 vm_object_deallocate(object); 1470 } 1471 return (error); 1472 } 1473 1474 /* 1475 * Internal version of mmap that maps a specific VM object into an 1476 * map. Called by mmap for MAP_ANON, vm_mmap, shm_mmap, and vn_mmap. 1477 */ 1478 int 1479 vm_mmap_object(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, 1480 vm_prot_t maxprot, int flags, vm_object_t object, vm_ooffset_t foff, 1481 boolean_t writecounted, struct thread *td) 1482 { 1483 boolean_t curmap, fitit; 1484 vm_offset_t max_addr; 1485 int docow, error, findspace, rv; 1486 1487 curmap = map == &td->td_proc->p_vmspace->vm_map; 1488 if (curmap) { 1489 RACCT_PROC_LOCK(td->td_proc); 1490 if (map->size + size > lim_cur(td, RLIMIT_VMEM)) { 1491 RACCT_PROC_UNLOCK(td->td_proc); 1492 return (ENOMEM); 1493 } 1494 if (racct_set(td->td_proc, RACCT_VMEM, map->size + size)) { 1495 RACCT_PROC_UNLOCK(td->td_proc); 1496 return (ENOMEM); 1497 } 1498 if (!old_mlock && map->flags & MAP_WIREFUTURE) { 1499 if (ptoa(pmap_wired_count(map->pmap)) + size > 1500 lim_cur(td, RLIMIT_MEMLOCK)) { 1501 racct_set_force(td->td_proc, RACCT_VMEM, 1502 map->size); 1503 RACCT_PROC_UNLOCK(td->td_proc); 1504 return (ENOMEM); 1505 } 1506 error = racct_set(td->td_proc, RACCT_MEMLOCK, 1507 ptoa(pmap_wired_count(map->pmap)) + size); 1508 if (error != 0) { 1509 racct_set_force(td->td_proc, RACCT_VMEM, 1510 map->size); 1511 RACCT_PROC_UNLOCK(td->td_proc); 1512 return (error); 1513 } 1514 } 1515 RACCT_PROC_UNLOCK(td->td_proc); 1516 } 1517 1518 /* 1519 * We currently can only deal with page aligned file offsets. 1520 * The mmap() system call already enforces this by subtracting 1521 * the page offset from the file offset, but checking here 1522 * catches errors in device drivers (e.g. d_single_mmap() 1523 * callbacks) and other internal mapping requests (such as in 1524 * exec). 1525 */ 1526 if (foff & PAGE_MASK) 1527 return (EINVAL); 1528 1529 if ((flags & MAP_FIXED) == 0) { 1530 fitit = TRUE; 1531 *addr = round_page(*addr); 1532 } else { 1533 if (*addr != trunc_page(*addr)) 1534 return (EINVAL); 1535 fitit = FALSE; 1536 } 1537 1538 if (flags & MAP_ANON) { 1539 if (object != NULL || foff != 0) 1540 return (EINVAL); 1541 docow = 0; 1542 } else if (flags & MAP_PREFAULT_READ) 1543 docow = MAP_PREFAULT; 1544 else 1545 docow = MAP_PREFAULT_PARTIAL; 1546 1547 if ((flags & (MAP_ANON|MAP_SHARED)) == 0) 1548 docow |= MAP_COPY_ON_WRITE; 1549 if (flags & MAP_NOSYNC) 1550 docow |= MAP_DISABLE_SYNCER; 1551 if (flags & MAP_NOCORE) 1552 docow |= MAP_DISABLE_COREDUMP; 1553 /* Shared memory is also shared with children. */ 1554 if (flags & MAP_SHARED) 1555 docow |= MAP_INHERIT_SHARE; 1556 if (writecounted) 1557 docow |= MAP_VN_WRITECOUNT; 1558 if (flags & MAP_STACK) { 1559 if (object != NULL) 1560 return (EINVAL); 1561 docow |= MAP_STACK_GROWS_DOWN; 1562 } 1563 if ((flags & MAP_EXCL) != 0) 1564 docow |= MAP_CHECK_EXCL; 1565 if ((flags & MAP_GUARD) != 0) 1566 docow |= MAP_CREATE_GUARD; 1567 1568 if (fitit) { 1569 if ((flags & MAP_ALIGNMENT_MASK) == MAP_ALIGNED_SUPER) 1570 findspace = VMFS_SUPER_SPACE; 1571 else if ((flags & MAP_ALIGNMENT_MASK) != 0) 1572 findspace = VMFS_ALIGNED_SPACE(flags >> 1573 MAP_ALIGNMENT_SHIFT); 1574 else 1575 findspace = VMFS_OPTIMAL_SPACE; 1576 max_addr = 0; 1577 #ifdef MAP_32BIT 1578 if ((flags & MAP_32BIT) != 0) 1579 max_addr = MAP_32BIT_MAX_ADDR; 1580 #endif 1581 if (curmap) { 1582 rv = vm_map_find_min(map, object, foff, addr, size, 1583 round_page((vm_offset_t)td->td_proc->p_vmspace-> 1584 vm_daddr + lim_max(td, RLIMIT_DATA)), max_addr, 1585 findspace, prot, maxprot, docow); 1586 } else { 1587 rv = vm_map_find(map, object, foff, addr, size, 1588 max_addr, findspace, prot, maxprot, docow); 1589 } 1590 } else { 1591 rv = vm_map_fixed(map, object, foff, *addr, size, 1592 prot, maxprot, docow); 1593 } 1594 1595 if (rv == KERN_SUCCESS) { 1596 /* 1597 * If the process has requested that all future mappings 1598 * be wired, then heed this. 1599 */ 1600 if ((map->flags & MAP_WIREFUTURE) != 0) { 1601 vm_map_lock(map); 1602 if ((map->flags & MAP_WIREFUTURE) != 0) 1603 (void)vm_map_wire_locked(map, *addr, 1604 *addr + size, VM_MAP_WIRE_USER | 1605 ((flags & MAP_STACK) ? VM_MAP_WIRE_HOLESOK : 1606 VM_MAP_WIRE_NOHOLES)); 1607 vm_map_unlock(map); 1608 } 1609 } 1610 return (vm_mmap_to_errno(rv)); 1611 } 1612 1613 /* 1614 * Translate a Mach VM return code to zero on success or the appropriate errno 1615 * on failure. 1616 */ 1617 int 1618 vm_mmap_to_errno(int rv) 1619 { 1620 1621 switch (rv) { 1622 case KERN_SUCCESS: 1623 return (0); 1624 case KERN_INVALID_ADDRESS: 1625 case KERN_NO_SPACE: 1626 return (ENOMEM); 1627 case KERN_PROTECTION_FAILURE: 1628 return (EACCES); 1629 default: 1630 return (EINVAL); 1631 } 1632 } 1633