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/elf.h> 59 #include <sys/filedesc.h> 60 #include <sys/priv.h> 61 #include <sys/proc.h> 62 #include <sys/procctl.h> 63 #include <sys/racct.h> 64 #include <sys/resource.h> 65 #include <sys/resourcevar.h> 66 #include <sys/rwlock.h> 67 #include <sys/sysctl.h> 68 #include <sys/vnode.h> 69 #include <sys/fcntl.h> 70 #include <sys/file.h> 71 #include <sys/mman.h> 72 #include <sys/mount.h> 73 #include <sys/conf.h> 74 #include <sys/stat.h> 75 #include <sys/syscallsubr.h> 76 #include <sys/sysent.h> 77 #include <sys/vmmeter.h> 78 #if defined(__amd64__) || defined(__i386__) /* for i386_read_exec */ 79 #include <machine/md_var.h> 80 #endif 81 82 #include <security/audit/audit.h> 83 #include <security/mac/mac_framework.h> 84 85 #include <vm/vm.h> 86 #include <vm/vm_param.h> 87 #include <vm/pmap.h> 88 #include <vm/vm_map.h> 89 #include <vm/vm_object.h> 90 #include <vm/vm_page.h> 91 #include <vm/vm_pager.h> 92 #include <vm/vm_pageout.h> 93 #include <vm/vm_extern.h> 94 #include <vm/vm_page.h> 95 #include <vm/vnode_pager.h> 96 97 #ifdef HWPMC_HOOKS 98 #include <sys/pmckern.h> 99 #endif 100 101 int old_mlock = 0; 102 SYSCTL_INT(_vm, OID_AUTO, old_mlock, CTLFLAG_RWTUN, &old_mlock, 0, 103 "Do not apply RLIMIT_MEMLOCK on mlockall"); 104 static int mincore_mapped = 1; 105 SYSCTL_INT(_vm, OID_AUTO, mincore_mapped, CTLFLAG_RWTUN, &mincore_mapped, 0, 106 "mincore reports mappings, not residency"); 107 static int imply_prot_max = 0; 108 SYSCTL_INT(_vm, OID_AUTO, imply_prot_max, CTLFLAG_RWTUN, &imply_prot_max, 0, 109 "Imply maximum page permissions in mmap() when none are specified"); 110 111 #ifdef MAP_32BIT 112 #define MAP_32BIT_MAX_ADDR ((vm_offset_t)1 << 31) 113 #endif 114 115 #ifndef _SYS_SYSPROTO_H_ 116 struct sbrk_args { 117 int incr; 118 }; 119 #endif 120 121 int 122 sys_sbrk(struct thread *td, struct sbrk_args *uap) 123 { 124 /* Not yet implemented */ 125 return (EOPNOTSUPP); 126 } 127 128 #ifndef _SYS_SYSPROTO_H_ 129 struct sstk_args { 130 int incr; 131 }; 132 #endif 133 134 int 135 sys_sstk(struct thread *td, struct sstk_args *uap) 136 { 137 /* Not yet implemented */ 138 return (EOPNOTSUPP); 139 } 140 141 #if defined(COMPAT_43) 142 int 143 ogetpagesize(struct thread *td, struct ogetpagesize_args *uap) 144 { 145 146 td->td_retval[0] = PAGE_SIZE; 147 return (0); 148 } 149 #endif /* COMPAT_43 */ 150 151 152 /* 153 * Memory Map (mmap) system call. Note that the file offset 154 * and address are allowed to be NOT page aligned, though if 155 * the MAP_FIXED flag it set, both must have the same remainder 156 * modulo the PAGE_SIZE (POSIX 1003.1b). If the address is not 157 * page-aligned, the actual mapping starts at trunc_page(addr) 158 * and the return value is adjusted up by the page offset. 159 * 160 * Generally speaking, only character devices which are themselves 161 * memory-based, such as a video framebuffer, can be mmap'd. Otherwise 162 * there would be no cache coherency between a descriptor and a VM mapping 163 * both to the same character device. 164 */ 165 #ifndef _SYS_SYSPROTO_H_ 166 struct mmap_args { 167 void *addr; 168 size_t len; 169 int prot; 170 int flags; 171 int fd; 172 long pad; 173 off_t pos; 174 }; 175 #endif 176 177 int 178 sys_mmap(struct thread *td, struct mmap_args *uap) 179 { 180 181 return (kern_mmap(td, (uintptr_t)uap->addr, uap->len, uap->prot, 182 uap->flags, uap->fd, uap->pos)); 183 } 184 185 int 186 kern_mmap_maxprot(struct proc *p, int prot) 187 { 188 189 if ((p->p_flag2 & P2_PROTMAX_DISABLE) != 0 || 190 (p->p_fctl0 & NT_FREEBSD_FCTL_PROTMAX_DISABLE) != 0) 191 return (_PROT_ALL); 192 if (((p->p_flag2 & P2_PROTMAX_ENABLE) != 0 || imply_prot_max) && 193 prot != PROT_NONE) 194 return (prot); 195 return (_PROT_ALL); 196 } 197 198 int 199 kern_mmap(struct thread *td, uintptr_t addr0, size_t len, int prot, int flags, 200 int fd, off_t pos) 201 { 202 203 return (kern_mmap_fpcheck(td, addr0, len, prot, flags, fd, pos, NULL)); 204 } 205 206 /* 207 * When mmap'ing a file, check_fp_fn may be used for the caller to do any 208 * last-minute validation based on the referenced file in a non-racy way. 209 */ 210 int 211 kern_mmap_fpcheck(struct thread *td, uintptr_t addr0, size_t len, int prot, 212 int flags, int fd, off_t pos, mmap_check_fp_fn check_fp_fn) 213 { 214 struct vmspace *vms; 215 struct file *fp; 216 struct proc *p; 217 vm_offset_t addr; 218 vm_size_t pageoff, size; 219 vm_prot_t cap_maxprot; 220 int align, error, max_prot; 221 cap_rights_t rights; 222 223 if ((prot & ~(_PROT_ALL | PROT_MAX(_PROT_ALL))) != 0) 224 return (EINVAL); 225 max_prot = PROT_MAX_EXTRACT(prot); 226 prot = PROT_EXTRACT(prot); 227 if (max_prot != 0 && (max_prot & prot) != prot) 228 return (ENOTSUP); 229 230 p = td->td_proc; 231 232 /* 233 * Always honor PROT_MAX if set. If not, default to all 234 * permissions unless we're implying maximum permissions. 235 */ 236 if (max_prot == 0) 237 max_prot = kern_mmap_maxprot(p, prot); 238 239 vms = p->p_vmspace; 240 fp = NULL; 241 AUDIT_ARG_FD(fd); 242 addr = addr0; 243 244 /* 245 * Ignore old flags that used to be defined but did not do anything. 246 */ 247 flags &= ~(MAP_RESERVED0020 | MAP_RESERVED0040); 248 249 /* 250 * Enforce the constraints. 251 * Mapping of length 0 is only allowed for old binaries. 252 * Anonymous mapping shall specify -1 as filedescriptor and 253 * zero position for new code. Be nice to ancient a.out 254 * binaries and correct pos for anonymous mapping, since old 255 * ld.so sometimes issues anonymous map requests with non-zero 256 * pos. 257 */ 258 if (!SV_CURPROC_FLAG(SV_AOUT)) { 259 if ((len == 0 && p->p_osrel >= P_OSREL_MAP_ANON) || 260 ((flags & MAP_ANON) != 0 && (fd != -1 || pos != 0))) 261 return (EINVAL); 262 } else { 263 if ((flags & MAP_ANON) != 0) 264 pos = 0; 265 } 266 267 if (flags & MAP_STACK) { 268 if ((fd != -1) || 269 ((prot & (PROT_READ | PROT_WRITE)) != (PROT_READ | PROT_WRITE))) 270 return (EINVAL); 271 flags |= MAP_ANON; 272 pos = 0; 273 } 274 if ((flags & ~(MAP_SHARED | MAP_PRIVATE | MAP_FIXED | MAP_HASSEMAPHORE | 275 MAP_STACK | MAP_NOSYNC | MAP_ANON | MAP_EXCL | MAP_NOCORE | 276 MAP_PREFAULT_READ | MAP_GUARD | 277 #ifdef MAP_32BIT 278 MAP_32BIT | 279 #endif 280 MAP_ALIGNMENT_MASK)) != 0) 281 return (EINVAL); 282 if ((flags & (MAP_EXCL | MAP_FIXED)) == MAP_EXCL) 283 return (EINVAL); 284 if ((flags & (MAP_SHARED | MAP_PRIVATE)) == (MAP_SHARED | MAP_PRIVATE)) 285 return (EINVAL); 286 if (prot != PROT_NONE && 287 (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC)) != 0) 288 return (EINVAL); 289 if ((flags & MAP_GUARD) != 0 && (prot != PROT_NONE || fd != -1 || 290 pos != 0 || (flags & ~(MAP_FIXED | MAP_GUARD | MAP_EXCL | 291 #ifdef MAP_32BIT 292 MAP_32BIT | 293 #endif 294 MAP_ALIGNMENT_MASK)) != 0)) 295 return (EINVAL); 296 297 /* 298 * Align the file position to a page boundary, 299 * and save its page offset component. 300 */ 301 pageoff = (pos & PAGE_MASK); 302 pos -= pageoff; 303 304 /* Compute size from len by rounding (on both ends). */ 305 size = len + pageoff; /* low end... */ 306 size = round_page(size); /* hi end */ 307 /* Check for rounding up to zero. */ 308 if (len > size) 309 return (ENOMEM); 310 311 /* Ensure alignment is at least a page and fits in a pointer. */ 312 align = flags & MAP_ALIGNMENT_MASK; 313 if (align != 0 && align != MAP_ALIGNED_SUPER && 314 (align >> MAP_ALIGNMENT_SHIFT >= sizeof(void *) * NBBY || 315 align >> MAP_ALIGNMENT_SHIFT < PAGE_SHIFT)) 316 return (EINVAL); 317 318 /* 319 * Check for illegal addresses. Watch out for address wrap... Note 320 * that VM_*_ADDRESS are not constants due to casts (argh). 321 */ 322 if (flags & MAP_FIXED) { 323 /* 324 * The specified address must have the same remainder 325 * as the file offset taken modulo PAGE_SIZE, so it 326 * should be aligned after adjustment by pageoff. 327 */ 328 addr -= pageoff; 329 if (addr & PAGE_MASK) 330 return (EINVAL); 331 332 /* Address range must be all in user VM space. */ 333 if (addr < vm_map_min(&vms->vm_map) || 334 addr + size > vm_map_max(&vms->vm_map)) 335 return (EINVAL); 336 if (addr + size < addr) 337 return (EINVAL); 338 #ifdef MAP_32BIT 339 if (flags & MAP_32BIT && addr + size > MAP_32BIT_MAX_ADDR) 340 return (EINVAL); 341 } else if (flags & MAP_32BIT) { 342 /* 343 * For MAP_32BIT, override the hint if it is too high and 344 * do not bother moving the mapping past the heap (since 345 * the heap is usually above 2GB). 346 */ 347 if (addr + size > MAP_32BIT_MAX_ADDR) 348 addr = 0; 349 #endif 350 } else { 351 /* 352 * XXX for non-fixed mappings where no hint is provided or 353 * the hint would fall in the potential heap space, 354 * place it after the end of the largest possible heap. 355 * 356 * There should really be a pmap call to determine a reasonable 357 * location. 358 */ 359 if (addr == 0 || 360 (addr >= round_page((vm_offset_t)vms->vm_taddr) && 361 addr < round_page((vm_offset_t)vms->vm_daddr + 362 lim_max(td, RLIMIT_DATA)))) 363 addr = round_page((vm_offset_t)vms->vm_daddr + 364 lim_max(td, RLIMIT_DATA)); 365 } 366 if (len == 0) { 367 /* 368 * Return success without mapping anything for old 369 * binaries that request a page-aligned mapping of 370 * length 0. For modern binaries, this function 371 * returns an error earlier. 372 */ 373 error = 0; 374 } else if ((flags & MAP_GUARD) != 0) { 375 error = vm_mmap_object(&vms->vm_map, &addr, size, VM_PROT_NONE, 376 VM_PROT_NONE, flags, NULL, pos, FALSE, td); 377 } else if ((flags & MAP_ANON) != 0) { 378 /* 379 * Mapping blank space is trivial. 380 * 381 * This relies on VM_PROT_* matching PROT_*. 382 */ 383 error = vm_mmap_object(&vms->vm_map, &addr, size, prot, 384 max_prot, flags, NULL, pos, FALSE, td); 385 } else { 386 /* 387 * Mapping file, get fp for validation and don't let the 388 * descriptor disappear on us if we block. Check capability 389 * rights, but also return the maximum rights to be combined 390 * with maxprot later. 391 */ 392 cap_rights_init_one(&rights, CAP_MMAP); 393 if (prot & PROT_READ) 394 cap_rights_set_one(&rights, CAP_MMAP_R); 395 if ((flags & MAP_SHARED) != 0) { 396 if (prot & PROT_WRITE) 397 cap_rights_set_one(&rights, CAP_MMAP_W); 398 } 399 if (prot & PROT_EXEC) 400 cap_rights_set_one(&rights, CAP_MMAP_X); 401 error = fget_mmap(td, fd, &rights, &cap_maxprot, &fp); 402 if (error != 0) 403 goto done; 404 if ((flags & (MAP_SHARED | MAP_PRIVATE)) == 0 && 405 p->p_osrel >= P_OSREL_MAP_FSTRICT) { 406 error = EINVAL; 407 goto done; 408 } 409 if (check_fp_fn != NULL) { 410 error = check_fp_fn(fp, prot, max_prot & cap_maxprot, 411 flags); 412 if (error != 0) 413 goto done; 414 } 415 /* This relies on VM_PROT_* matching PROT_*. */ 416 error = fo_mmap(fp, &vms->vm_map, &addr, size, prot, 417 max_prot & cap_maxprot, flags, pos, td); 418 } 419 420 if (error == 0) 421 td->td_retval[0] = (register_t) (addr + pageoff); 422 done: 423 if (fp) 424 fdrop(fp, td); 425 426 return (error); 427 } 428 429 #if defined(COMPAT_FREEBSD6) 430 int 431 freebsd6_mmap(struct thread *td, struct freebsd6_mmap_args *uap) 432 { 433 434 return (kern_mmap(td, (uintptr_t)uap->addr, uap->len, uap->prot, 435 uap->flags, uap->fd, uap->pos)); 436 } 437 #endif 438 439 #ifdef COMPAT_43 440 #ifndef _SYS_SYSPROTO_H_ 441 struct ommap_args { 442 caddr_t addr; 443 int len; 444 int prot; 445 int flags; 446 int fd; 447 long pos; 448 }; 449 #endif 450 int 451 ommap(struct thread *td, struct ommap_args *uap) 452 { 453 static const char cvtbsdprot[8] = { 454 0, 455 PROT_EXEC, 456 PROT_WRITE, 457 PROT_EXEC | PROT_WRITE, 458 PROT_READ, 459 PROT_EXEC | PROT_READ, 460 PROT_WRITE | PROT_READ, 461 PROT_EXEC | PROT_WRITE | PROT_READ, 462 }; 463 int flags, prot; 464 465 #define OMAP_ANON 0x0002 466 #define OMAP_COPY 0x0020 467 #define OMAP_SHARED 0x0010 468 #define OMAP_FIXED 0x0100 469 470 prot = cvtbsdprot[uap->prot & 0x7]; 471 #if (defined(COMPAT_FREEBSD32) && defined(__amd64__)) || defined(__i386__) 472 if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32) && 473 prot != 0) 474 prot |= PROT_EXEC; 475 #endif 476 flags = 0; 477 if (uap->flags & OMAP_ANON) 478 flags |= MAP_ANON; 479 if (uap->flags & OMAP_COPY) 480 flags |= MAP_COPY; 481 if (uap->flags & OMAP_SHARED) 482 flags |= MAP_SHARED; 483 else 484 flags |= MAP_PRIVATE; 485 if (uap->flags & OMAP_FIXED) 486 flags |= MAP_FIXED; 487 return (kern_mmap(td, (uintptr_t)uap->addr, uap->len, prot, flags, 488 uap->fd, uap->pos)); 489 } 490 #endif /* COMPAT_43 */ 491 492 493 #ifndef _SYS_SYSPROTO_H_ 494 struct msync_args { 495 void *addr; 496 size_t len; 497 int flags; 498 }; 499 #endif 500 int 501 sys_msync(struct thread *td, struct msync_args *uap) 502 { 503 504 return (kern_msync(td, (uintptr_t)uap->addr, uap->len, uap->flags)); 505 } 506 507 int 508 kern_msync(struct thread *td, uintptr_t addr0, size_t size, int flags) 509 { 510 vm_offset_t addr; 511 vm_size_t pageoff; 512 vm_map_t map; 513 int rv; 514 515 addr = addr0; 516 pageoff = (addr & PAGE_MASK); 517 addr -= pageoff; 518 size += pageoff; 519 size = (vm_size_t) round_page(size); 520 if (addr + size < addr) 521 return (EINVAL); 522 523 if ((flags & (MS_ASYNC|MS_INVALIDATE)) == (MS_ASYNC|MS_INVALIDATE)) 524 return (EINVAL); 525 526 map = &td->td_proc->p_vmspace->vm_map; 527 528 /* 529 * Clean the pages and interpret the return value. 530 */ 531 rv = vm_map_sync(map, addr, addr + size, (flags & MS_ASYNC) == 0, 532 (flags & MS_INVALIDATE) != 0); 533 switch (rv) { 534 case KERN_SUCCESS: 535 return (0); 536 case KERN_INVALID_ADDRESS: 537 return (ENOMEM); 538 case KERN_INVALID_ARGUMENT: 539 return (EBUSY); 540 case KERN_FAILURE: 541 return (EIO); 542 default: 543 return (EINVAL); 544 } 545 } 546 547 #ifndef _SYS_SYSPROTO_H_ 548 struct munmap_args { 549 void *addr; 550 size_t len; 551 }; 552 #endif 553 int 554 sys_munmap(struct thread *td, struct munmap_args *uap) 555 { 556 557 return (kern_munmap(td, (uintptr_t)uap->addr, uap->len)); 558 } 559 560 int 561 kern_munmap(struct thread *td, uintptr_t addr0, size_t size) 562 { 563 #ifdef HWPMC_HOOKS 564 struct pmckern_map_out pkm; 565 vm_map_entry_t entry; 566 bool pmc_handled; 567 #endif 568 vm_offset_t addr; 569 vm_size_t pageoff; 570 vm_map_t map; 571 572 if (size == 0) 573 return (EINVAL); 574 575 addr = addr0; 576 pageoff = (addr & PAGE_MASK); 577 addr -= pageoff; 578 size += pageoff; 579 size = (vm_size_t) round_page(size); 580 if (addr + size < addr) 581 return (EINVAL); 582 583 /* 584 * Check for illegal addresses. Watch out for address wrap... 585 */ 586 map = &td->td_proc->p_vmspace->vm_map; 587 if (addr < vm_map_min(map) || addr + size > vm_map_max(map)) 588 return (EINVAL); 589 vm_map_lock(map); 590 #ifdef HWPMC_HOOKS 591 pmc_handled = false; 592 if (PMC_HOOK_INSTALLED(PMC_FN_MUNMAP)) { 593 pmc_handled = true; 594 /* 595 * Inform hwpmc if the address range being unmapped contains 596 * an executable region. 597 */ 598 pkm.pm_address = (uintptr_t) NULL; 599 if (vm_map_lookup_entry(map, addr, &entry)) { 600 for (; entry->start < addr + size; 601 entry = vm_map_entry_succ(entry)) { 602 if (vm_map_check_protection(map, entry->start, 603 entry->end, VM_PROT_EXECUTE) == TRUE) { 604 pkm.pm_address = (uintptr_t) addr; 605 pkm.pm_size = (size_t) size; 606 break; 607 } 608 } 609 } 610 } 611 #endif 612 vm_map_delete(map, addr, addr + size); 613 614 #ifdef HWPMC_HOOKS 615 if (__predict_false(pmc_handled)) { 616 /* downgrade the lock to prevent a LOR with the pmc-sx lock */ 617 vm_map_lock_downgrade(map); 618 if (pkm.pm_address != (uintptr_t) NULL) 619 PMC_CALL_HOOK(td, PMC_FN_MUNMAP, (void *) &pkm); 620 vm_map_unlock_read(map); 621 } else 622 #endif 623 vm_map_unlock(map); 624 625 /* vm_map_delete returns nothing but KERN_SUCCESS anyway */ 626 return (0); 627 } 628 629 #ifndef _SYS_SYSPROTO_H_ 630 struct mprotect_args { 631 const void *addr; 632 size_t len; 633 int prot; 634 }; 635 #endif 636 int 637 sys_mprotect(struct thread *td, struct mprotect_args *uap) 638 { 639 640 return (kern_mprotect(td, (uintptr_t)uap->addr, uap->len, uap->prot)); 641 } 642 643 int 644 kern_mprotect(struct thread *td, uintptr_t addr0, size_t size, int prot) 645 { 646 vm_offset_t addr; 647 vm_size_t pageoff; 648 int vm_error, max_prot; 649 650 addr = addr0; 651 if ((prot & ~(_PROT_ALL | PROT_MAX(_PROT_ALL))) != 0) 652 return (EINVAL); 653 max_prot = PROT_MAX_EXTRACT(prot); 654 prot = PROT_EXTRACT(prot); 655 pageoff = (addr & PAGE_MASK); 656 addr -= pageoff; 657 size += pageoff; 658 size = (vm_size_t) round_page(size); 659 #ifdef COMPAT_FREEBSD32 660 if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) { 661 if (((addr + size) & 0xffffffff) < addr) 662 return (EINVAL); 663 } else 664 #endif 665 if (addr + size < addr) 666 return (EINVAL); 667 668 vm_error = KERN_SUCCESS; 669 if (max_prot != 0) { 670 if ((max_prot & prot) != prot) 671 return (ENOTSUP); 672 vm_error = vm_map_protect(&td->td_proc->p_vmspace->vm_map, 673 addr, addr + size, max_prot, TRUE); 674 } 675 if (vm_error == KERN_SUCCESS) 676 vm_error = vm_map_protect(&td->td_proc->p_vmspace->vm_map, 677 addr, addr + size, prot, FALSE); 678 679 switch (vm_error) { 680 case KERN_SUCCESS: 681 return (0); 682 case KERN_PROTECTION_FAILURE: 683 return (EACCES); 684 case KERN_RESOURCE_SHORTAGE: 685 return (ENOMEM); 686 } 687 return (EINVAL); 688 } 689 690 #ifndef _SYS_SYSPROTO_H_ 691 struct minherit_args { 692 void *addr; 693 size_t len; 694 int inherit; 695 }; 696 #endif 697 int 698 sys_minherit(struct thread *td, struct minherit_args *uap) 699 { 700 vm_offset_t addr; 701 vm_size_t size, pageoff; 702 vm_inherit_t inherit; 703 704 addr = (vm_offset_t)uap->addr; 705 size = uap->len; 706 inherit = uap->inherit; 707 708 pageoff = (addr & PAGE_MASK); 709 addr -= pageoff; 710 size += pageoff; 711 size = (vm_size_t) round_page(size); 712 if (addr + size < addr) 713 return (EINVAL); 714 715 switch (vm_map_inherit(&td->td_proc->p_vmspace->vm_map, addr, 716 addr + size, inherit)) { 717 case KERN_SUCCESS: 718 return (0); 719 case KERN_PROTECTION_FAILURE: 720 return (EACCES); 721 } 722 return (EINVAL); 723 } 724 725 #ifndef _SYS_SYSPROTO_H_ 726 struct madvise_args { 727 void *addr; 728 size_t len; 729 int behav; 730 }; 731 #endif 732 733 int 734 sys_madvise(struct thread *td, struct madvise_args *uap) 735 { 736 737 return (kern_madvise(td, (uintptr_t)uap->addr, uap->len, uap->behav)); 738 } 739 740 int 741 kern_madvise(struct thread *td, uintptr_t addr0, size_t len, int behav) 742 { 743 vm_map_t map; 744 vm_offset_t addr, end, start; 745 int flags; 746 747 /* 748 * Check for our special case, advising the swap pager we are 749 * "immortal." 750 */ 751 if (behav == MADV_PROTECT) { 752 flags = PPROT_SET; 753 return (kern_procctl(td, P_PID, td->td_proc->p_pid, 754 PROC_SPROTECT, &flags)); 755 } 756 757 /* 758 * Check for illegal addresses. Watch out for address wrap... Note 759 * that VM_*_ADDRESS are not constants due to casts (argh). 760 */ 761 map = &td->td_proc->p_vmspace->vm_map; 762 addr = addr0; 763 if (addr < vm_map_min(map) || addr + len > vm_map_max(map)) 764 return (EINVAL); 765 if ((addr + len) < addr) 766 return (EINVAL); 767 768 /* 769 * Since this routine is only advisory, we default to conservative 770 * behavior. 771 */ 772 start = trunc_page(addr); 773 end = round_page(addr + len); 774 775 /* 776 * vm_map_madvise() checks for illegal values of behav. 777 */ 778 return (vm_map_madvise(map, start, end, behav)); 779 } 780 781 #ifndef _SYS_SYSPROTO_H_ 782 struct mincore_args { 783 const void *addr; 784 size_t len; 785 char *vec; 786 }; 787 #endif 788 789 int 790 sys_mincore(struct thread *td, struct mincore_args *uap) 791 { 792 793 return (kern_mincore(td, (uintptr_t)uap->addr, uap->len, uap->vec)); 794 } 795 796 int 797 kern_mincore(struct thread *td, uintptr_t addr0, size_t len, char *vec) 798 { 799 pmap_t pmap; 800 vm_map_t map; 801 vm_map_entry_t current, entry; 802 vm_object_t object; 803 vm_offset_t addr, cend, end, first_addr; 804 vm_paddr_t pa; 805 vm_page_t m; 806 vm_pindex_t pindex; 807 int error, lastvecindex, mincoreinfo, vecindex; 808 unsigned int timestamp; 809 810 /* 811 * Make sure that the addresses presented are valid for user 812 * mode. 813 */ 814 first_addr = addr = trunc_page(addr0); 815 end = round_page(addr0 + len); 816 map = &td->td_proc->p_vmspace->vm_map; 817 if (end > vm_map_max(map) || end < addr) 818 return (ENOMEM); 819 820 pmap = vmspace_pmap(td->td_proc->p_vmspace); 821 822 vm_map_lock_read(map); 823 RestartScan: 824 timestamp = map->timestamp; 825 826 if (!vm_map_lookup_entry(map, addr, &entry)) { 827 vm_map_unlock_read(map); 828 return (ENOMEM); 829 } 830 831 /* 832 * Do this on a map entry basis so that if the pages are not 833 * in the current processes address space, we can easily look 834 * up the pages elsewhere. 835 */ 836 lastvecindex = -1; 837 while (entry->start < end) { 838 839 /* 840 * check for contiguity 841 */ 842 current = entry; 843 entry = vm_map_entry_succ(current); 844 if (current->end < end && 845 entry->start > current->end) { 846 vm_map_unlock_read(map); 847 return (ENOMEM); 848 } 849 850 /* 851 * ignore submaps (for now) or null objects 852 */ 853 if ((current->eflags & MAP_ENTRY_IS_SUB_MAP) || 854 current->object.vm_object == NULL) 855 continue; 856 857 /* 858 * limit this scan to the current map entry and the 859 * limits for the mincore call 860 */ 861 if (addr < current->start) 862 addr = current->start; 863 cend = current->end; 864 if (cend > end) 865 cend = end; 866 867 for (; addr < cend; addr += PAGE_SIZE) { 868 /* 869 * Check pmap first, it is likely faster, also 870 * it can provide info as to whether we are the 871 * one referencing or modifying the page. 872 */ 873 m = NULL; 874 object = NULL; 875 retry: 876 pa = 0; 877 mincoreinfo = pmap_mincore(pmap, addr, &pa); 878 if (mincore_mapped) { 879 /* 880 * We only care about this pmap's 881 * mapping of the page, if any. 882 */ 883 ; 884 } else if (pa != 0) { 885 /* 886 * The page is mapped by this process but not 887 * both accessed and modified. It is also 888 * managed. Acquire the object lock so that 889 * other mappings might be examined. The page's 890 * identity may change at any point before its 891 * object lock is acquired, so re-validate if 892 * necessary. 893 */ 894 m = PHYS_TO_VM_PAGE(pa); 895 while (object == NULL || m->object != object) { 896 if (object != NULL) 897 VM_OBJECT_WUNLOCK(object); 898 object = atomic_load_ptr(&m->object); 899 if (object == NULL) 900 goto retry; 901 VM_OBJECT_WLOCK(object); 902 } 903 if (pa != pmap_extract(pmap, addr)) 904 goto retry; 905 KASSERT(vm_page_all_valid(m), 906 ("mincore: page %p is mapped but invalid", 907 m)); 908 } else if (mincoreinfo == 0) { 909 /* 910 * The page is not mapped by this process. If 911 * the object implements managed pages, then 912 * determine if the page is resident so that 913 * the mappings might be examined. 914 */ 915 if (current->object.vm_object != object) { 916 if (object != NULL) 917 VM_OBJECT_WUNLOCK(object); 918 object = current->object.vm_object; 919 VM_OBJECT_WLOCK(object); 920 } 921 if (object->type == OBJT_DEFAULT || 922 object->type == OBJT_SWAP || 923 object->type == OBJT_VNODE) { 924 pindex = OFF_TO_IDX(current->offset + 925 (addr - current->start)); 926 m = vm_page_lookup(object, pindex); 927 if (m != NULL && vm_page_none_valid(m)) 928 m = NULL; 929 if (m != NULL) 930 mincoreinfo = MINCORE_INCORE; 931 } 932 } 933 if (m != NULL) { 934 VM_OBJECT_ASSERT_WLOCKED(m->object); 935 936 /* Examine other mappings of the page. */ 937 if (m->dirty == 0 && pmap_is_modified(m)) 938 vm_page_dirty(m); 939 if (m->dirty != 0) 940 mincoreinfo |= MINCORE_MODIFIED_OTHER; 941 942 /* 943 * The first test for PGA_REFERENCED is an 944 * optimization. The second test is 945 * required because a concurrent pmap 946 * operation could clear the last reference 947 * and set PGA_REFERENCED before the call to 948 * pmap_is_referenced(). 949 */ 950 if ((m->a.flags & PGA_REFERENCED) != 0 || 951 pmap_is_referenced(m) || 952 (m->a.flags & PGA_REFERENCED) != 0) 953 mincoreinfo |= MINCORE_REFERENCED_OTHER; 954 } 955 if (object != NULL) 956 VM_OBJECT_WUNLOCK(object); 957 958 /* 959 * subyte may page fault. In case it needs to modify 960 * the map, we release the lock. 961 */ 962 vm_map_unlock_read(map); 963 964 /* 965 * calculate index into user supplied byte vector 966 */ 967 vecindex = atop(addr - first_addr); 968 969 /* 970 * If we have skipped map entries, we need to make sure that 971 * the byte vector is zeroed for those skipped entries. 972 */ 973 while ((lastvecindex + 1) < vecindex) { 974 ++lastvecindex; 975 error = subyte(vec + lastvecindex, 0); 976 if (error) { 977 error = EFAULT; 978 goto done2; 979 } 980 } 981 982 /* 983 * Pass the page information to the user 984 */ 985 error = subyte(vec + vecindex, mincoreinfo); 986 if (error) { 987 error = EFAULT; 988 goto done2; 989 } 990 991 /* 992 * If the map has changed, due to the subyte, the previous 993 * output may be invalid. 994 */ 995 vm_map_lock_read(map); 996 if (timestamp != map->timestamp) 997 goto RestartScan; 998 999 lastvecindex = vecindex; 1000 } 1001 } 1002 1003 /* 1004 * subyte may page fault. In case it needs to modify 1005 * the map, we release the lock. 1006 */ 1007 vm_map_unlock_read(map); 1008 1009 /* 1010 * Zero the last entries in the byte vector. 1011 */ 1012 vecindex = atop(end - first_addr); 1013 while ((lastvecindex + 1) < vecindex) { 1014 ++lastvecindex; 1015 error = subyte(vec + lastvecindex, 0); 1016 if (error) { 1017 error = EFAULT; 1018 goto done2; 1019 } 1020 } 1021 1022 /* 1023 * If the map has changed, due to the subyte, the previous 1024 * output may be invalid. 1025 */ 1026 vm_map_lock_read(map); 1027 if (timestamp != map->timestamp) 1028 goto RestartScan; 1029 vm_map_unlock_read(map); 1030 done2: 1031 return (error); 1032 } 1033 1034 #ifndef _SYS_SYSPROTO_H_ 1035 struct mlock_args { 1036 const void *addr; 1037 size_t len; 1038 }; 1039 #endif 1040 int 1041 sys_mlock(struct thread *td, struct mlock_args *uap) 1042 { 1043 1044 return (kern_mlock(td->td_proc, td->td_ucred, 1045 __DECONST(uintptr_t, uap->addr), uap->len)); 1046 } 1047 1048 int 1049 kern_mlock(struct proc *proc, struct ucred *cred, uintptr_t addr0, size_t len) 1050 { 1051 vm_offset_t addr, end, last, start; 1052 vm_size_t npages, size; 1053 vm_map_t map; 1054 unsigned long nsize; 1055 int error; 1056 1057 error = priv_check_cred(cred, PRIV_VM_MLOCK); 1058 if (error) 1059 return (error); 1060 addr = addr0; 1061 size = len; 1062 last = addr + size; 1063 start = trunc_page(addr); 1064 end = round_page(last); 1065 if (last < addr || end < addr) 1066 return (EINVAL); 1067 npages = atop(end - start); 1068 if (npages > vm_page_max_user_wired) 1069 return (ENOMEM); 1070 map = &proc->p_vmspace->vm_map; 1071 PROC_LOCK(proc); 1072 nsize = ptoa(npages + pmap_wired_count(map->pmap)); 1073 if (nsize > lim_cur_proc(proc, RLIMIT_MEMLOCK)) { 1074 PROC_UNLOCK(proc); 1075 return (ENOMEM); 1076 } 1077 PROC_UNLOCK(proc); 1078 #ifdef RACCT 1079 if (racct_enable) { 1080 PROC_LOCK(proc); 1081 error = racct_set(proc, RACCT_MEMLOCK, nsize); 1082 PROC_UNLOCK(proc); 1083 if (error != 0) 1084 return (ENOMEM); 1085 } 1086 #endif 1087 error = vm_map_wire(map, start, end, 1088 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); 1089 #ifdef RACCT 1090 if (racct_enable && error != KERN_SUCCESS) { 1091 PROC_LOCK(proc); 1092 racct_set(proc, RACCT_MEMLOCK, 1093 ptoa(pmap_wired_count(map->pmap))); 1094 PROC_UNLOCK(proc); 1095 } 1096 #endif 1097 return (error == KERN_SUCCESS ? 0 : ENOMEM); 1098 } 1099 1100 #ifndef _SYS_SYSPROTO_H_ 1101 struct mlockall_args { 1102 int how; 1103 }; 1104 #endif 1105 1106 int 1107 sys_mlockall(struct thread *td, struct mlockall_args *uap) 1108 { 1109 vm_map_t map; 1110 int error; 1111 1112 map = &td->td_proc->p_vmspace->vm_map; 1113 error = priv_check(td, PRIV_VM_MLOCK); 1114 if (error) 1115 return (error); 1116 1117 if ((uap->how == 0) || ((uap->how & ~(MCL_CURRENT|MCL_FUTURE)) != 0)) 1118 return (EINVAL); 1119 1120 /* 1121 * If wiring all pages in the process would cause it to exceed 1122 * a hard resource limit, return ENOMEM. 1123 */ 1124 if (!old_mlock && uap->how & MCL_CURRENT) { 1125 if (map->size > lim_cur(td, RLIMIT_MEMLOCK)) 1126 return (ENOMEM); 1127 } 1128 #ifdef RACCT 1129 if (racct_enable) { 1130 PROC_LOCK(td->td_proc); 1131 error = racct_set(td->td_proc, RACCT_MEMLOCK, map->size); 1132 PROC_UNLOCK(td->td_proc); 1133 if (error != 0) 1134 return (ENOMEM); 1135 } 1136 #endif 1137 1138 if (uap->how & MCL_FUTURE) { 1139 vm_map_lock(map); 1140 vm_map_modflags(map, MAP_WIREFUTURE, 0); 1141 vm_map_unlock(map); 1142 error = 0; 1143 } 1144 1145 if (uap->how & MCL_CURRENT) { 1146 /* 1147 * P1003.1-2001 mandates that all currently mapped pages 1148 * will be memory resident and locked (wired) upon return 1149 * from mlockall(). vm_map_wire() will wire pages, by 1150 * calling vm_fault_wire() for each page in the region. 1151 */ 1152 error = vm_map_wire(map, vm_map_min(map), vm_map_max(map), 1153 VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); 1154 if (error == KERN_SUCCESS) 1155 error = 0; 1156 else if (error == KERN_RESOURCE_SHORTAGE) 1157 error = ENOMEM; 1158 else 1159 error = EAGAIN; 1160 } 1161 #ifdef RACCT 1162 if (racct_enable && error != KERN_SUCCESS) { 1163 PROC_LOCK(td->td_proc); 1164 racct_set(td->td_proc, RACCT_MEMLOCK, 1165 ptoa(pmap_wired_count(map->pmap))); 1166 PROC_UNLOCK(td->td_proc); 1167 } 1168 #endif 1169 1170 return (error); 1171 } 1172 1173 #ifndef _SYS_SYSPROTO_H_ 1174 struct munlockall_args { 1175 register_t dummy; 1176 }; 1177 #endif 1178 1179 int 1180 sys_munlockall(struct thread *td, struct munlockall_args *uap) 1181 { 1182 vm_map_t map; 1183 int error; 1184 1185 map = &td->td_proc->p_vmspace->vm_map; 1186 error = priv_check(td, PRIV_VM_MUNLOCK); 1187 if (error) 1188 return (error); 1189 1190 /* Clear the MAP_WIREFUTURE flag from this vm_map. */ 1191 vm_map_lock(map); 1192 vm_map_modflags(map, 0, MAP_WIREFUTURE); 1193 vm_map_unlock(map); 1194 1195 /* Forcibly unwire all pages. */ 1196 error = vm_map_unwire(map, vm_map_min(map), vm_map_max(map), 1197 VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); 1198 #ifdef RACCT 1199 if (racct_enable && error == KERN_SUCCESS) { 1200 PROC_LOCK(td->td_proc); 1201 racct_set(td->td_proc, RACCT_MEMLOCK, 0); 1202 PROC_UNLOCK(td->td_proc); 1203 } 1204 #endif 1205 1206 return (error); 1207 } 1208 1209 #ifndef _SYS_SYSPROTO_H_ 1210 struct munlock_args { 1211 const void *addr; 1212 size_t len; 1213 }; 1214 #endif 1215 int 1216 sys_munlock(struct thread *td, struct munlock_args *uap) 1217 { 1218 1219 return (kern_munlock(td, (uintptr_t)uap->addr, uap->len)); 1220 } 1221 1222 int 1223 kern_munlock(struct thread *td, uintptr_t addr0, size_t size) 1224 { 1225 vm_offset_t addr, end, last, start; 1226 #ifdef RACCT 1227 vm_map_t map; 1228 #endif 1229 int error; 1230 1231 error = priv_check(td, PRIV_VM_MUNLOCK); 1232 if (error) 1233 return (error); 1234 addr = addr0; 1235 last = addr + size; 1236 start = trunc_page(addr); 1237 end = round_page(last); 1238 if (last < addr || end < addr) 1239 return (EINVAL); 1240 error = vm_map_unwire(&td->td_proc->p_vmspace->vm_map, start, end, 1241 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); 1242 #ifdef RACCT 1243 if (racct_enable && error == KERN_SUCCESS) { 1244 PROC_LOCK(td->td_proc); 1245 map = &td->td_proc->p_vmspace->vm_map; 1246 racct_set(td->td_proc, RACCT_MEMLOCK, 1247 ptoa(pmap_wired_count(map->pmap))); 1248 PROC_UNLOCK(td->td_proc); 1249 } 1250 #endif 1251 return (error == KERN_SUCCESS ? 0 : ENOMEM); 1252 } 1253 1254 /* 1255 * vm_mmap_vnode() 1256 * 1257 * Helper function for vm_mmap. Perform sanity check specific for mmap 1258 * operations on vnodes. 1259 */ 1260 int 1261 vm_mmap_vnode(struct thread *td, vm_size_t objsize, 1262 vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, 1263 struct vnode *vp, vm_ooffset_t *foffp, vm_object_t *objp, 1264 boolean_t *writecounted) 1265 { 1266 struct vattr va; 1267 vm_object_t obj; 1268 vm_ooffset_t foff; 1269 struct ucred *cred; 1270 int error, flags; 1271 bool writex; 1272 1273 cred = td->td_ucred; 1274 writex = (*maxprotp & VM_PROT_WRITE) != 0 && 1275 (*flagsp & MAP_SHARED) != 0; 1276 if ((error = vget(vp, LK_SHARED, td)) != 0) 1277 return (error); 1278 AUDIT_ARG_VNODE1(vp); 1279 foff = *foffp; 1280 flags = *flagsp; 1281 obj = vp->v_object; 1282 if (vp->v_type == VREG) { 1283 /* 1284 * Get the proper underlying object 1285 */ 1286 if (obj == NULL) { 1287 error = EINVAL; 1288 goto done; 1289 } 1290 if (obj->type == OBJT_VNODE && obj->handle != vp) { 1291 vput(vp); 1292 vp = (struct vnode *)obj->handle; 1293 /* 1294 * Bypass filesystems obey the mpsafety of the 1295 * underlying fs. Tmpfs never bypasses. 1296 */ 1297 error = vget(vp, LK_SHARED, td); 1298 if (error != 0) 1299 return (error); 1300 } 1301 if (writex) { 1302 *writecounted = TRUE; 1303 vm_pager_update_writecount(obj, 0, objsize); 1304 } 1305 } else { 1306 error = EINVAL; 1307 goto done; 1308 } 1309 if ((error = VOP_GETATTR(vp, &va, cred))) 1310 goto done; 1311 #ifdef MAC 1312 /* This relies on VM_PROT_* matching PROT_*. */ 1313 error = mac_vnode_check_mmap(cred, vp, (int)prot, flags); 1314 if (error != 0) 1315 goto done; 1316 #endif 1317 if ((flags & MAP_SHARED) != 0) { 1318 if ((va.va_flags & (SF_SNAPSHOT|IMMUTABLE|APPEND)) != 0) { 1319 if (prot & VM_PROT_WRITE) { 1320 error = EPERM; 1321 goto done; 1322 } 1323 *maxprotp &= ~VM_PROT_WRITE; 1324 } 1325 } 1326 /* 1327 * If it is a regular file without any references 1328 * we do not need to sync it. 1329 * Adjust object size to be the size of actual file. 1330 */ 1331 objsize = round_page(va.va_size); 1332 if (va.va_nlink == 0) 1333 flags |= MAP_NOSYNC; 1334 if (obj->type == OBJT_VNODE) { 1335 obj = vm_pager_allocate(OBJT_VNODE, vp, objsize, prot, foff, 1336 cred); 1337 if (obj == NULL) { 1338 error = ENOMEM; 1339 goto done; 1340 } 1341 } else { 1342 KASSERT(obj->type == OBJT_DEFAULT || obj->type == OBJT_SWAP, 1343 ("wrong object type")); 1344 vm_object_reference(obj); 1345 #if VM_NRESERVLEVEL > 0 1346 if ((obj->flags & OBJ_COLORED) == 0) { 1347 VM_OBJECT_WLOCK(obj); 1348 vm_object_color(obj, 0); 1349 VM_OBJECT_WUNLOCK(obj); 1350 } 1351 #endif 1352 } 1353 *objp = obj; 1354 *flagsp = flags; 1355 1356 VOP_MMAPPED(vp); 1357 1358 done: 1359 if (error != 0 && *writecounted) { 1360 *writecounted = FALSE; 1361 vm_pager_update_writecount(obj, objsize, 0); 1362 } 1363 vput(vp); 1364 return (error); 1365 } 1366 1367 /* 1368 * vm_mmap_cdev() 1369 * 1370 * Helper function for vm_mmap. Perform sanity check specific for mmap 1371 * operations on cdevs. 1372 */ 1373 int 1374 vm_mmap_cdev(struct thread *td, vm_size_t objsize, vm_prot_t prot, 1375 vm_prot_t *maxprotp, int *flagsp, struct cdev *cdev, struct cdevsw *dsw, 1376 vm_ooffset_t *foff, vm_object_t *objp) 1377 { 1378 vm_object_t obj; 1379 int error, flags; 1380 1381 flags = *flagsp; 1382 1383 if (dsw->d_flags & D_MMAP_ANON) { 1384 *objp = NULL; 1385 *foff = 0; 1386 *maxprotp = VM_PROT_ALL; 1387 *flagsp |= MAP_ANON; 1388 return (0); 1389 } 1390 /* 1391 * cdevs do not provide private mappings of any kind. 1392 */ 1393 if ((*maxprotp & VM_PROT_WRITE) == 0 && 1394 (prot & VM_PROT_WRITE) != 0) 1395 return (EACCES); 1396 if (flags & (MAP_PRIVATE|MAP_COPY)) 1397 return (EINVAL); 1398 /* 1399 * Force device mappings to be shared. 1400 */ 1401 flags |= MAP_SHARED; 1402 #ifdef MAC_XXX 1403 error = mac_cdev_check_mmap(td->td_ucred, cdev, (int)prot); 1404 if (error != 0) 1405 return (error); 1406 #endif 1407 /* 1408 * First, try d_mmap_single(). If that is not implemented 1409 * (returns ENODEV), fall back to using the device pager. 1410 * Note that d_mmap_single() must return a reference to the 1411 * object (it needs to bump the reference count of the object 1412 * it returns somehow). 1413 * 1414 * XXX assumes VM_PROT_* == PROT_* 1415 */ 1416 error = dsw->d_mmap_single(cdev, foff, objsize, objp, (int)prot); 1417 if (error != ENODEV) 1418 return (error); 1419 obj = vm_pager_allocate(OBJT_DEVICE, cdev, objsize, prot, *foff, 1420 td->td_ucred); 1421 if (obj == NULL) 1422 return (EINVAL); 1423 *objp = obj; 1424 *flagsp = flags; 1425 return (0); 1426 } 1427 1428 /* 1429 * vm_mmap() 1430 * 1431 * Internal version of mmap used by exec, sys5 shared memory, and 1432 * various device drivers. Handle is either a vnode pointer, a 1433 * character device, or NULL for MAP_ANON. 1434 */ 1435 int 1436 vm_mmap(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, 1437 vm_prot_t maxprot, int flags, 1438 objtype_t handle_type, void *handle, 1439 vm_ooffset_t foff) 1440 { 1441 vm_object_t object; 1442 struct thread *td = curthread; 1443 int error; 1444 boolean_t writecounted; 1445 1446 if (size == 0) 1447 return (EINVAL); 1448 1449 size = round_page(size); 1450 object = NULL; 1451 writecounted = FALSE; 1452 1453 /* 1454 * Lookup/allocate object. 1455 */ 1456 switch (handle_type) { 1457 case OBJT_DEVICE: { 1458 struct cdevsw *dsw; 1459 struct cdev *cdev; 1460 int ref; 1461 1462 cdev = handle; 1463 dsw = dev_refthread(cdev, &ref); 1464 if (dsw == NULL) 1465 return (ENXIO); 1466 error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, cdev, 1467 dsw, &foff, &object); 1468 dev_relthread(cdev, ref); 1469 break; 1470 } 1471 case OBJT_VNODE: 1472 error = vm_mmap_vnode(td, size, prot, &maxprot, &flags, 1473 handle, &foff, &object, &writecounted); 1474 break; 1475 case OBJT_DEFAULT: 1476 if (handle == NULL) { 1477 error = 0; 1478 break; 1479 } 1480 /* FALLTHROUGH */ 1481 default: 1482 error = EINVAL; 1483 break; 1484 } 1485 if (error) 1486 return (error); 1487 1488 error = vm_mmap_object(map, addr, size, prot, maxprot, flags, object, 1489 foff, writecounted, td); 1490 if (error != 0 && object != NULL) { 1491 /* 1492 * If this mapping was accounted for in the vnode's 1493 * writecount, then undo that now. 1494 */ 1495 if (writecounted) 1496 vm_pager_release_writecount(object, 0, size); 1497 vm_object_deallocate(object); 1498 } 1499 return (error); 1500 } 1501 1502 /* 1503 * Internal version of mmap that maps a specific VM object into an 1504 * map. Called by mmap for MAP_ANON, vm_mmap, shm_mmap, and vn_mmap. 1505 */ 1506 int 1507 vm_mmap_object(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, 1508 vm_prot_t maxprot, int flags, vm_object_t object, vm_ooffset_t foff, 1509 boolean_t writecounted, struct thread *td) 1510 { 1511 boolean_t curmap, fitit; 1512 vm_offset_t max_addr; 1513 int docow, error, findspace, rv; 1514 1515 curmap = map == &td->td_proc->p_vmspace->vm_map; 1516 if (curmap) { 1517 RACCT_PROC_LOCK(td->td_proc); 1518 if (map->size + size > lim_cur(td, RLIMIT_VMEM)) { 1519 RACCT_PROC_UNLOCK(td->td_proc); 1520 return (ENOMEM); 1521 } 1522 if (racct_set(td->td_proc, RACCT_VMEM, map->size + size)) { 1523 RACCT_PROC_UNLOCK(td->td_proc); 1524 return (ENOMEM); 1525 } 1526 if (!old_mlock && map->flags & MAP_WIREFUTURE) { 1527 if (ptoa(pmap_wired_count(map->pmap)) + size > 1528 lim_cur(td, RLIMIT_MEMLOCK)) { 1529 racct_set_force(td->td_proc, RACCT_VMEM, 1530 map->size); 1531 RACCT_PROC_UNLOCK(td->td_proc); 1532 return (ENOMEM); 1533 } 1534 error = racct_set(td->td_proc, RACCT_MEMLOCK, 1535 ptoa(pmap_wired_count(map->pmap)) + size); 1536 if (error != 0) { 1537 racct_set_force(td->td_proc, RACCT_VMEM, 1538 map->size); 1539 RACCT_PROC_UNLOCK(td->td_proc); 1540 return (error); 1541 } 1542 } 1543 RACCT_PROC_UNLOCK(td->td_proc); 1544 } 1545 1546 /* 1547 * We currently can only deal with page aligned file offsets. 1548 * The mmap() system call already enforces this by subtracting 1549 * the page offset from the file offset, but checking here 1550 * catches errors in device drivers (e.g. d_single_mmap() 1551 * callbacks) and other internal mapping requests (such as in 1552 * exec). 1553 */ 1554 if (foff & PAGE_MASK) 1555 return (EINVAL); 1556 1557 if ((flags & MAP_FIXED) == 0) { 1558 fitit = TRUE; 1559 *addr = round_page(*addr); 1560 } else { 1561 if (*addr != trunc_page(*addr)) 1562 return (EINVAL); 1563 fitit = FALSE; 1564 } 1565 1566 if (flags & MAP_ANON) { 1567 if (object != NULL || foff != 0) 1568 return (EINVAL); 1569 docow = 0; 1570 } else if (flags & MAP_PREFAULT_READ) 1571 docow = MAP_PREFAULT; 1572 else 1573 docow = MAP_PREFAULT_PARTIAL; 1574 1575 if ((flags & (MAP_ANON|MAP_SHARED)) == 0) 1576 docow |= MAP_COPY_ON_WRITE; 1577 if (flags & MAP_NOSYNC) 1578 docow |= MAP_DISABLE_SYNCER; 1579 if (flags & MAP_NOCORE) 1580 docow |= MAP_DISABLE_COREDUMP; 1581 /* Shared memory is also shared with children. */ 1582 if (flags & MAP_SHARED) 1583 docow |= MAP_INHERIT_SHARE; 1584 if (writecounted) 1585 docow |= MAP_WRITECOUNT; 1586 if (flags & MAP_STACK) { 1587 if (object != NULL) 1588 return (EINVAL); 1589 docow |= MAP_STACK_GROWS_DOWN; 1590 } 1591 if ((flags & MAP_EXCL) != 0) 1592 docow |= MAP_CHECK_EXCL; 1593 if ((flags & MAP_GUARD) != 0) 1594 docow |= MAP_CREATE_GUARD; 1595 1596 if (fitit) { 1597 if ((flags & MAP_ALIGNMENT_MASK) == MAP_ALIGNED_SUPER) 1598 findspace = VMFS_SUPER_SPACE; 1599 else if ((flags & MAP_ALIGNMENT_MASK) != 0) 1600 findspace = VMFS_ALIGNED_SPACE(flags >> 1601 MAP_ALIGNMENT_SHIFT); 1602 else 1603 findspace = VMFS_OPTIMAL_SPACE; 1604 max_addr = 0; 1605 #ifdef MAP_32BIT 1606 if ((flags & MAP_32BIT) != 0) 1607 max_addr = MAP_32BIT_MAX_ADDR; 1608 #endif 1609 if (curmap) { 1610 rv = vm_map_find_min(map, object, foff, addr, size, 1611 round_page((vm_offset_t)td->td_proc->p_vmspace-> 1612 vm_daddr + lim_max(td, RLIMIT_DATA)), max_addr, 1613 findspace, prot, maxprot, docow); 1614 } else { 1615 rv = vm_map_find(map, object, foff, addr, size, 1616 max_addr, findspace, prot, maxprot, docow); 1617 } 1618 } else { 1619 rv = vm_map_fixed(map, object, foff, *addr, size, 1620 prot, maxprot, docow); 1621 } 1622 1623 if (rv == KERN_SUCCESS) { 1624 /* 1625 * If the process has requested that all future mappings 1626 * be wired, then heed this. 1627 */ 1628 if ((map->flags & MAP_WIREFUTURE) != 0) { 1629 vm_map_lock(map); 1630 if ((map->flags & MAP_WIREFUTURE) != 0) 1631 (void)vm_map_wire_locked(map, *addr, 1632 *addr + size, VM_MAP_WIRE_USER | 1633 ((flags & MAP_STACK) ? VM_MAP_WIRE_HOLESOK : 1634 VM_MAP_WIRE_NOHOLES)); 1635 vm_map_unlock(map); 1636 } 1637 } 1638 return (vm_mmap_to_errno(rv)); 1639 } 1640 1641 /* 1642 * Translate a Mach VM return code to zero on success or the appropriate errno 1643 * on failure. 1644 */ 1645 int 1646 vm_mmap_to_errno(int rv) 1647 { 1648 1649 switch (rv) { 1650 case KERN_SUCCESS: 1651 return (0); 1652 case KERN_INVALID_ADDRESS: 1653 case KERN_NO_SPACE: 1654 return (ENOMEM); 1655 case KERN_PROTECTION_FAILURE: 1656 return (EACCES); 1657 default: 1658 return (EINVAL); 1659 } 1660 } 1661