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 protections 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 _Static_assert(MAXPAGESIZES <= 4, "MINCORE_SUPER too narrow"); 116 117 #ifndef _SYS_SYSPROTO_H_ 118 struct sbrk_args { 119 int incr; 120 }; 121 #endif 122 123 int 124 sys_sbrk(struct thread *td, struct sbrk_args *uap) 125 { 126 /* Not yet implemented */ 127 return (EOPNOTSUPP); 128 } 129 130 #ifndef _SYS_SYSPROTO_H_ 131 struct sstk_args { 132 int incr; 133 }; 134 #endif 135 136 int 137 sys_sstk(struct thread *td, struct sstk_args *uap) 138 { 139 /* Not yet implemented */ 140 return (EOPNOTSUPP); 141 } 142 143 #if defined(COMPAT_43) 144 int 145 ogetpagesize(struct thread *td, struct ogetpagesize_args *uap) 146 { 147 148 td->td_retval[0] = PAGE_SIZE; 149 return (0); 150 } 151 #endif /* COMPAT_43 */ 152 153 /* 154 * Memory Map (mmap) system call. Note that the file offset 155 * and address are allowed to be NOT page aligned, though if 156 * the MAP_FIXED flag it set, both must have the same remainder 157 * modulo the PAGE_SIZE (POSIX 1003.1b). If the address is not 158 * page-aligned, the actual mapping starts at trunc_page(addr) 159 * and the return value is adjusted up by the page offset. 160 * 161 * Generally speaking, only character devices which are themselves 162 * memory-based, such as a video framebuffer, can be mmap'd. Otherwise 163 * there would be no cache coherency between a descriptor and a VM mapping 164 * both to the same character device. 165 */ 166 #ifndef _SYS_SYSPROTO_H_ 167 struct mmap_args { 168 void *addr; 169 size_t len; 170 int prot; 171 int flags; 172 int fd; 173 long pad; 174 off_t pos; 175 }; 176 #endif 177 178 int 179 sys_mmap(struct thread *td, struct mmap_args *uap) 180 { 181 182 return (kern_mmap(td, &(struct mmap_req){ 183 .mr_hint = (uintptr_t)uap->addr, 184 .mr_len = uap->len, 185 .mr_prot = uap->prot, 186 .mr_flags = uap->flags, 187 .mr_fd = uap->fd, 188 .mr_pos = uap->pos, 189 })); 190 } 191 192 int 193 kern_mmap_maxprot(struct proc *p, int prot) 194 { 195 196 if ((p->p_flag2 & P2_PROTMAX_DISABLE) != 0 || 197 (p->p_fctl0 & NT_FREEBSD_FCTL_PROTMAX_DISABLE) != 0) 198 return (_PROT_ALL); 199 if (((p->p_flag2 & P2_PROTMAX_ENABLE) != 0 || imply_prot_max) && 200 prot != PROT_NONE) 201 return (prot); 202 return (_PROT_ALL); 203 } 204 205 int 206 kern_mmap(struct thread *td, const struct mmap_req *mrp) 207 { 208 struct vmspace *vms; 209 struct file *fp; 210 struct proc *p; 211 off_t pos; 212 vm_offset_t addr, orig_addr; 213 vm_size_t len, pageoff, size; 214 vm_prot_t cap_maxprot; 215 int align, error, fd, flags, max_prot, prot; 216 cap_rights_t rights; 217 mmap_check_fp_fn check_fp_fn; 218 219 orig_addr = addr = mrp->mr_hint; 220 len = mrp->mr_len; 221 prot = mrp->mr_prot; 222 flags = mrp->mr_flags; 223 fd = mrp->mr_fd; 224 pos = mrp->mr_pos; 225 check_fp_fn = mrp->mr_check_fp_fn; 226 227 if ((prot & ~(_PROT_ALL | PROT_MAX(_PROT_ALL))) != 0) 228 return (EINVAL); 229 max_prot = PROT_MAX_EXTRACT(prot); 230 prot = PROT_EXTRACT(prot); 231 if (max_prot != 0 && (max_prot & prot) != prot) 232 return (ENOTSUP); 233 234 p = td->td_proc; 235 236 /* 237 * Always honor PROT_MAX if set. If not, default to all 238 * permissions unless we're implying maximum permissions. 239 */ 240 if (max_prot == 0) 241 max_prot = kern_mmap_maxprot(p, prot); 242 243 vms = p->p_vmspace; 244 fp = NULL; 245 AUDIT_ARG_FD(fd); 246 247 /* 248 * Ignore old flags that used to be defined but did not do anything. 249 */ 250 flags &= ~(MAP_RESERVED0020 | MAP_RESERVED0040); 251 252 /* 253 * Enforce the constraints. 254 * Mapping of length 0 is only allowed for old binaries. 255 * Anonymous mapping shall specify -1 as filedescriptor and 256 * zero position for new code. Be nice to ancient a.out 257 * binaries and correct pos for anonymous mapping, since old 258 * ld.so sometimes issues anonymous map requests with non-zero 259 * pos. 260 */ 261 if (!SV_CURPROC_FLAG(SV_AOUT)) { 262 if ((len == 0 && p->p_osrel >= P_OSREL_MAP_ANON) || 263 ((flags & MAP_ANON) != 0 && (fd != -1 || pos != 0))) 264 return (EINVAL); 265 } else { 266 if ((flags & MAP_ANON) != 0) 267 pos = 0; 268 } 269 270 if (flags & MAP_STACK) { 271 if ((fd != -1) || 272 ((prot & (PROT_READ | PROT_WRITE)) != (PROT_READ | PROT_WRITE))) 273 return (EINVAL); 274 flags |= MAP_ANON; 275 pos = 0; 276 } 277 if ((flags & ~(MAP_SHARED | MAP_PRIVATE | MAP_FIXED | MAP_HASSEMAPHORE | 278 MAP_STACK | MAP_NOSYNC | MAP_ANON | MAP_EXCL | MAP_NOCORE | 279 MAP_PREFAULT_READ | MAP_GUARD | 280 #ifdef MAP_32BIT 281 MAP_32BIT | 282 #endif 283 MAP_ALIGNMENT_MASK)) != 0) 284 return (EINVAL); 285 if ((flags & (MAP_EXCL | MAP_FIXED)) == MAP_EXCL) 286 return (EINVAL); 287 if ((flags & (MAP_SHARED | MAP_PRIVATE)) == (MAP_SHARED | MAP_PRIVATE)) 288 return (EINVAL); 289 if (prot != PROT_NONE && 290 (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC)) != 0) 291 return (EINVAL); 292 if ((flags & MAP_GUARD) != 0 && (prot != PROT_NONE || fd != -1 || 293 pos != 0 || (flags & ~(MAP_FIXED | MAP_GUARD | MAP_EXCL | 294 #ifdef MAP_32BIT 295 MAP_32BIT | 296 #endif 297 MAP_ALIGNMENT_MASK)) != 0)) 298 return (EINVAL); 299 300 /* 301 * Align the file position to a page boundary, 302 * and save its page offset component. 303 */ 304 pageoff = (pos & PAGE_MASK); 305 pos -= pageoff; 306 307 /* Compute size from len by rounding (on both ends). */ 308 size = len + pageoff; /* low end... */ 309 size = round_page(size); /* hi end */ 310 /* Check for rounding up to zero. */ 311 if (len > size) 312 return (ENOMEM); 313 314 /* Ensure alignment is at least a page and fits in a pointer. */ 315 align = flags & MAP_ALIGNMENT_MASK; 316 if (align != 0 && align != MAP_ALIGNED_SUPER && 317 (align >> MAP_ALIGNMENT_SHIFT >= sizeof(void *) * NBBY || 318 align >> MAP_ALIGNMENT_SHIFT < PAGE_SHIFT)) 319 return (EINVAL); 320 321 /* 322 * Check for illegal addresses. Watch out for address wrap... Note 323 * that VM_*_ADDRESS are not constants due to casts (argh). 324 */ 325 if (flags & MAP_FIXED) { 326 /* 327 * The specified address must have the same remainder 328 * as the file offset taken modulo PAGE_SIZE, so it 329 * should be aligned after adjustment by pageoff. 330 */ 331 addr -= pageoff; 332 if (addr & PAGE_MASK) 333 return (EINVAL); 334 335 /* Address range must be all in user VM space. */ 336 if (!vm_map_range_valid(&vms->vm_map, addr, addr + size)) 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 if (fp->f_ops == &shm_ops && shm_largepage(fp->f_data)) 416 addr = orig_addr; 417 /* This relies on VM_PROT_* matching PROT_*. */ 418 error = fo_mmap(fp, &vms->vm_map, &addr, size, prot, 419 max_prot & cap_maxprot, flags, pos, td); 420 } 421 422 if (error == 0) 423 td->td_retval[0] = (register_t) (addr + pageoff); 424 done: 425 if (fp) 426 fdrop(fp, td); 427 428 return (error); 429 } 430 431 #if defined(COMPAT_FREEBSD6) 432 int 433 freebsd6_mmap(struct thread *td, struct freebsd6_mmap_args *uap) 434 { 435 return (kern_mmap(td, &(struct mmap_req){ 436 .mr_hint = (uintptr_t)uap->addr, 437 .mr_len = uap->len, 438 .mr_prot = uap->prot, 439 .mr_flags = uap->flags, 440 .mr_fd = uap->fd, 441 .mr_pos = uap->pos, 442 })); 443 } 444 #endif 445 446 #ifdef COMPAT_43 447 #ifndef _SYS_SYSPROTO_H_ 448 struct ommap_args { 449 caddr_t addr; 450 int len; 451 int prot; 452 int flags; 453 int fd; 454 long pos; 455 }; 456 #endif 457 int 458 ommap(struct thread *td, struct ommap_args *uap) 459 { 460 static const char cvtbsdprot[8] = { 461 0, 462 PROT_EXEC, 463 PROT_WRITE, 464 PROT_EXEC | PROT_WRITE, 465 PROT_READ, 466 PROT_EXEC | PROT_READ, 467 PROT_WRITE | PROT_READ, 468 PROT_EXEC | PROT_WRITE | PROT_READ, 469 }; 470 int flags, prot; 471 472 #define OMAP_ANON 0x0002 473 #define OMAP_COPY 0x0020 474 #define OMAP_SHARED 0x0010 475 #define OMAP_FIXED 0x0100 476 477 prot = cvtbsdprot[uap->prot & 0x7]; 478 #if (defined(COMPAT_FREEBSD32) && defined(__amd64__)) || defined(__i386__) 479 if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32) && 480 prot != 0) 481 prot |= PROT_EXEC; 482 #endif 483 flags = 0; 484 if (uap->flags & OMAP_ANON) 485 flags |= MAP_ANON; 486 if (uap->flags & OMAP_COPY) 487 flags |= MAP_COPY; 488 if (uap->flags & OMAP_SHARED) 489 flags |= MAP_SHARED; 490 else 491 flags |= MAP_PRIVATE; 492 if (uap->flags & OMAP_FIXED) 493 flags |= MAP_FIXED; 494 return (kern_mmap(td, &(struct mmap_req){ 495 .mr_hint = (uintptr_t)uap->addr, 496 .mr_len = uap->len, 497 .mr_prot = prot, 498 .mr_flags = flags, 499 .mr_fd = uap->fd, 500 .mr_pos = uap->pos, 501 })); 502 } 503 #endif /* COMPAT_43 */ 504 505 #ifndef _SYS_SYSPROTO_H_ 506 struct msync_args { 507 void *addr; 508 size_t len; 509 int flags; 510 }; 511 #endif 512 int 513 sys_msync(struct thread *td, struct msync_args *uap) 514 { 515 516 return (kern_msync(td, (uintptr_t)uap->addr, uap->len, uap->flags)); 517 } 518 519 int 520 kern_msync(struct thread *td, uintptr_t addr0, size_t size, int flags) 521 { 522 vm_offset_t addr; 523 vm_size_t pageoff; 524 vm_map_t map; 525 int rv; 526 527 addr = addr0; 528 pageoff = (addr & PAGE_MASK); 529 addr -= pageoff; 530 size += pageoff; 531 size = (vm_size_t) round_page(size); 532 if (addr + size < addr) 533 return (EINVAL); 534 535 if ((flags & (MS_ASYNC|MS_INVALIDATE)) == (MS_ASYNC|MS_INVALIDATE)) 536 return (EINVAL); 537 538 map = &td->td_proc->p_vmspace->vm_map; 539 540 /* 541 * Clean the pages and interpret the return value. 542 */ 543 rv = vm_map_sync(map, addr, addr + size, (flags & MS_ASYNC) == 0, 544 (flags & MS_INVALIDATE) != 0); 545 switch (rv) { 546 case KERN_SUCCESS: 547 return (0); 548 case KERN_INVALID_ADDRESS: 549 return (ENOMEM); 550 case KERN_INVALID_ARGUMENT: 551 return (EBUSY); 552 case KERN_FAILURE: 553 return (EIO); 554 default: 555 return (EINVAL); 556 } 557 } 558 559 #ifndef _SYS_SYSPROTO_H_ 560 struct munmap_args { 561 void *addr; 562 size_t len; 563 }; 564 #endif 565 int 566 sys_munmap(struct thread *td, struct munmap_args *uap) 567 { 568 569 return (kern_munmap(td, (uintptr_t)uap->addr, uap->len)); 570 } 571 572 int 573 kern_munmap(struct thread *td, uintptr_t addr0, size_t size) 574 { 575 #ifdef HWPMC_HOOKS 576 struct pmckern_map_out pkm; 577 vm_map_entry_t entry; 578 bool pmc_handled; 579 #endif 580 vm_offset_t addr, end; 581 vm_size_t pageoff; 582 vm_map_t map; 583 int rv; 584 585 if (size == 0) 586 return (EINVAL); 587 588 addr = addr0; 589 pageoff = (addr & PAGE_MASK); 590 addr -= pageoff; 591 size += pageoff; 592 size = (vm_size_t) round_page(size); 593 end = addr + size; 594 map = &td->td_proc->p_vmspace->vm_map; 595 if (!vm_map_range_valid(map, addr, end)) 596 return (EINVAL); 597 598 vm_map_lock(map); 599 #ifdef HWPMC_HOOKS 600 pmc_handled = false; 601 if (PMC_HOOK_INSTALLED(PMC_FN_MUNMAP)) { 602 pmc_handled = true; 603 /* 604 * Inform hwpmc if the address range being unmapped contains 605 * an executable region. 606 */ 607 pkm.pm_address = (uintptr_t) NULL; 608 if (vm_map_lookup_entry(map, addr, &entry)) { 609 for (; entry->start < end; 610 entry = vm_map_entry_succ(entry)) { 611 if (vm_map_check_protection(map, entry->start, 612 entry->end, VM_PROT_EXECUTE) == TRUE) { 613 pkm.pm_address = (uintptr_t) addr; 614 pkm.pm_size = (size_t) size; 615 break; 616 } 617 } 618 } 619 } 620 #endif 621 rv = vm_map_delete(map, addr, end); 622 623 #ifdef HWPMC_HOOKS 624 if (rv == KERN_SUCCESS && __predict_false(pmc_handled)) { 625 /* downgrade the lock to prevent a LOR with the pmc-sx lock */ 626 vm_map_lock_downgrade(map); 627 if (pkm.pm_address != (uintptr_t) NULL) 628 PMC_CALL_HOOK(td, PMC_FN_MUNMAP, (void *) &pkm); 629 vm_map_unlock_read(map); 630 } else 631 #endif 632 vm_map_unlock(map); 633 634 return (vm_mmap_to_errno(rv)); 635 } 636 637 #ifndef _SYS_SYSPROTO_H_ 638 struct mprotect_args { 639 const void *addr; 640 size_t len; 641 int prot; 642 }; 643 #endif 644 int 645 sys_mprotect(struct thread *td, struct mprotect_args *uap) 646 { 647 648 return (kern_mprotect(td, (uintptr_t)uap->addr, uap->len, uap->prot)); 649 } 650 651 int 652 kern_mprotect(struct thread *td, uintptr_t addr0, size_t size, int prot) 653 { 654 vm_offset_t addr; 655 vm_size_t pageoff; 656 int vm_error, max_prot; 657 int flags; 658 659 addr = addr0; 660 if ((prot & ~(_PROT_ALL | PROT_MAX(_PROT_ALL))) != 0) 661 return (EINVAL); 662 max_prot = PROT_MAX_EXTRACT(prot); 663 prot = PROT_EXTRACT(prot); 664 pageoff = (addr & PAGE_MASK); 665 addr -= pageoff; 666 size += pageoff; 667 size = (vm_size_t) round_page(size); 668 #ifdef COMPAT_FREEBSD32 669 if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) { 670 if (((addr + size) & 0xffffffff) < addr) 671 return (EINVAL); 672 } else 673 #endif 674 if (addr + size < addr) 675 return (EINVAL); 676 677 flags = VM_MAP_PROTECT_SET_PROT; 678 if (max_prot != 0) 679 flags |= VM_MAP_PROTECT_SET_MAXPROT; 680 vm_error = vm_map_protect(&td->td_proc->p_vmspace->vm_map, 681 addr, addr + size, prot, max_prot, flags); 682 683 switch (vm_error) { 684 case KERN_SUCCESS: 685 return (0); 686 case KERN_PROTECTION_FAILURE: 687 return (EACCES); 688 case KERN_RESOURCE_SHORTAGE: 689 return (ENOMEM); 690 case KERN_OUT_OF_BOUNDS: 691 return (ENOTSUP); 692 } 693 return (EINVAL); 694 } 695 696 #ifndef _SYS_SYSPROTO_H_ 697 struct minherit_args { 698 void *addr; 699 size_t len; 700 int inherit; 701 }; 702 #endif 703 int 704 sys_minherit(struct thread *td, struct minherit_args *uap) 705 { 706 707 return (kern_minherit(td, (uintptr_t)uap->addr, uap->len, 708 uap->inherit)); 709 } 710 711 int 712 kern_minherit(struct thread *td, uintptr_t addr0, size_t len, int inherit0) 713 { 714 vm_offset_t addr; 715 vm_size_t size, pageoff; 716 vm_inherit_t inherit; 717 718 addr = (vm_offset_t)addr0; 719 size = len; 720 inherit = inherit0; 721 722 pageoff = (addr & PAGE_MASK); 723 addr -= pageoff; 724 size += pageoff; 725 size = (vm_size_t) round_page(size); 726 if (addr + size < addr) 727 return (EINVAL); 728 729 switch (vm_map_inherit(&td->td_proc->p_vmspace->vm_map, addr, 730 addr + size, inherit)) { 731 case KERN_SUCCESS: 732 return (0); 733 case KERN_PROTECTION_FAILURE: 734 return (EACCES); 735 } 736 return (EINVAL); 737 } 738 739 #ifndef _SYS_SYSPROTO_H_ 740 struct madvise_args { 741 void *addr; 742 size_t len; 743 int behav; 744 }; 745 #endif 746 747 int 748 sys_madvise(struct thread *td, struct madvise_args *uap) 749 { 750 751 return (kern_madvise(td, (uintptr_t)uap->addr, uap->len, uap->behav)); 752 } 753 754 int 755 kern_madvise(struct thread *td, uintptr_t addr0, size_t len, int behav) 756 { 757 vm_map_t map; 758 vm_offset_t addr, end, start; 759 int flags; 760 761 /* 762 * Check for our special case, advising the swap pager we are 763 * "immortal." 764 */ 765 if (behav == MADV_PROTECT) { 766 flags = PPROT_SET; 767 return (kern_procctl(td, P_PID, td->td_proc->p_pid, 768 PROC_SPROTECT, &flags)); 769 } 770 771 /* 772 * Check for illegal addresses. Watch out for address wrap... Note 773 * that VM_*_ADDRESS are not constants due to casts (argh). 774 */ 775 map = &td->td_proc->p_vmspace->vm_map; 776 addr = addr0; 777 if (!vm_map_range_valid(map, addr, addr + len)) 778 return (EINVAL); 779 780 /* 781 * Since this routine is only advisory, we default to conservative 782 * behavior. 783 */ 784 start = trunc_page(addr); 785 end = round_page(addr + len); 786 787 /* 788 * vm_map_madvise() checks for illegal values of behav. 789 */ 790 return (vm_map_madvise(map, start, end, behav)); 791 } 792 793 #ifndef _SYS_SYSPROTO_H_ 794 struct mincore_args { 795 const void *addr; 796 size_t len; 797 char *vec; 798 }; 799 #endif 800 801 int 802 sys_mincore(struct thread *td, struct mincore_args *uap) 803 { 804 805 return (kern_mincore(td, (uintptr_t)uap->addr, uap->len, uap->vec)); 806 } 807 808 int 809 kern_mincore(struct thread *td, uintptr_t addr0, size_t len, char *vec) 810 { 811 pmap_t pmap; 812 vm_map_t map; 813 vm_map_entry_t current, entry; 814 vm_object_t object; 815 vm_offset_t addr, cend, end, first_addr; 816 vm_paddr_t pa; 817 vm_page_t m; 818 vm_pindex_t pindex; 819 int error, lastvecindex, mincoreinfo, vecindex; 820 unsigned int timestamp; 821 822 /* 823 * Make sure that the addresses presented are valid for user 824 * mode. 825 */ 826 first_addr = addr = trunc_page(addr0); 827 end = round_page(addr0 + len); 828 map = &td->td_proc->p_vmspace->vm_map; 829 if (end > vm_map_max(map) || end < addr) 830 return (ENOMEM); 831 832 pmap = vmspace_pmap(td->td_proc->p_vmspace); 833 834 vm_map_lock_read(map); 835 RestartScan: 836 timestamp = map->timestamp; 837 838 if (!vm_map_lookup_entry(map, addr, &entry)) { 839 vm_map_unlock_read(map); 840 return (ENOMEM); 841 } 842 843 /* 844 * Do this on a map entry basis so that if the pages are not 845 * in the current processes address space, we can easily look 846 * up the pages elsewhere. 847 */ 848 lastvecindex = -1; 849 while (entry->start < end) { 850 /* 851 * check for contiguity 852 */ 853 current = entry; 854 entry = vm_map_entry_succ(current); 855 if (current->end < end && 856 entry->start > current->end) { 857 vm_map_unlock_read(map); 858 return (ENOMEM); 859 } 860 861 /* 862 * ignore submaps (for now) or null objects 863 */ 864 if ((current->eflags & MAP_ENTRY_IS_SUB_MAP) || 865 current->object.vm_object == NULL) 866 continue; 867 868 /* 869 * limit this scan to the current map entry and the 870 * limits for the mincore call 871 */ 872 if (addr < current->start) 873 addr = current->start; 874 cend = current->end; 875 if (cend > end) 876 cend = end; 877 878 for (; addr < cend; addr += PAGE_SIZE) { 879 /* 880 * Check pmap first, it is likely faster, also 881 * it can provide info as to whether we are the 882 * one referencing or modifying the page. 883 */ 884 m = NULL; 885 object = NULL; 886 retry: 887 pa = 0; 888 mincoreinfo = pmap_mincore(pmap, addr, &pa); 889 if (mincore_mapped) { 890 /* 891 * We only care about this pmap's 892 * mapping of the page, if any. 893 */ 894 ; 895 } else if (pa != 0) { 896 /* 897 * The page is mapped by this process but not 898 * both accessed and modified. It is also 899 * managed. Acquire the object lock so that 900 * other mappings might be examined. The page's 901 * identity may change at any point before its 902 * object lock is acquired, so re-validate if 903 * necessary. 904 */ 905 m = PHYS_TO_VM_PAGE(pa); 906 while (object == NULL || m->object != object) { 907 if (object != NULL) 908 VM_OBJECT_WUNLOCK(object); 909 object = atomic_load_ptr(&m->object); 910 if (object == NULL) 911 goto retry; 912 VM_OBJECT_WLOCK(object); 913 } 914 if (pa != pmap_extract(pmap, addr)) 915 goto retry; 916 KASSERT(vm_page_all_valid(m), 917 ("mincore: page %p is mapped but invalid", 918 m)); 919 } else if (mincoreinfo == 0) { 920 /* 921 * The page is not mapped by this process. If 922 * the object implements managed pages, then 923 * determine if the page is resident so that 924 * the mappings might be examined. 925 */ 926 if (current->object.vm_object != object) { 927 if (object != NULL) 928 VM_OBJECT_WUNLOCK(object); 929 object = current->object.vm_object; 930 VM_OBJECT_WLOCK(object); 931 } 932 if (object->type == OBJT_DEFAULT || 933 (object->flags & OBJ_SWAP) != 0 || 934 object->type == OBJT_VNODE) { 935 pindex = OFF_TO_IDX(current->offset + 936 (addr - current->start)); 937 m = vm_page_lookup(object, pindex); 938 if (m != NULL && vm_page_none_valid(m)) 939 m = NULL; 940 if (m != NULL) 941 mincoreinfo = MINCORE_INCORE; 942 } 943 } 944 if (m != NULL) { 945 VM_OBJECT_ASSERT_WLOCKED(m->object); 946 947 /* Examine other mappings of the page. */ 948 if (m->dirty == 0 && pmap_is_modified(m)) 949 vm_page_dirty(m); 950 if (m->dirty != 0) 951 mincoreinfo |= MINCORE_MODIFIED_OTHER; 952 953 /* 954 * The first test for PGA_REFERENCED is an 955 * optimization. The second test is 956 * required because a concurrent pmap 957 * operation could clear the last reference 958 * and set PGA_REFERENCED before the call to 959 * pmap_is_referenced(). 960 */ 961 if ((m->a.flags & PGA_REFERENCED) != 0 || 962 pmap_is_referenced(m) || 963 (m->a.flags & PGA_REFERENCED) != 0) 964 mincoreinfo |= MINCORE_REFERENCED_OTHER; 965 } 966 if (object != NULL) 967 VM_OBJECT_WUNLOCK(object); 968 969 /* 970 * subyte may page fault. In case it needs to modify 971 * the map, we release the lock. 972 */ 973 vm_map_unlock_read(map); 974 975 /* 976 * calculate index into user supplied byte vector 977 */ 978 vecindex = atop(addr - first_addr); 979 980 /* 981 * If we have skipped map entries, we need to make sure that 982 * the byte vector is zeroed for those skipped entries. 983 */ 984 while ((lastvecindex + 1) < vecindex) { 985 ++lastvecindex; 986 error = subyte(vec + lastvecindex, 0); 987 if (error) { 988 error = EFAULT; 989 goto done2; 990 } 991 } 992 993 /* 994 * Pass the page information to the user 995 */ 996 error = subyte(vec + vecindex, mincoreinfo); 997 if (error) { 998 error = EFAULT; 999 goto done2; 1000 } 1001 1002 /* 1003 * If the map has changed, due to the subyte, the previous 1004 * output may be invalid. 1005 */ 1006 vm_map_lock_read(map); 1007 if (timestamp != map->timestamp) 1008 goto RestartScan; 1009 1010 lastvecindex = vecindex; 1011 } 1012 } 1013 1014 /* 1015 * subyte may page fault. In case it needs to modify 1016 * the map, we release the lock. 1017 */ 1018 vm_map_unlock_read(map); 1019 1020 /* 1021 * Zero the last entries in the byte vector. 1022 */ 1023 vecindex = atop(end - first_addr); 1024 while ((lastvecindex + 1) < vecindex) { 1025 ++lastvecindex; 1026 error = subyte(vec + lastvecindex, 0); 1027 if (error) { 1028 error = EFAULT; 1029 goto done2; 1030 } 1031 } 1032 1033 /* 1034 * If the map has changed, due to the subyte, the previous 1035 * output may be invalid. 1036 */ 1037 vm_map_lock_read(map); 1038 if (timestamp != map->timestamp) 1039 goto RestartScan; 1040 vm_map_unlock_read(map); 1041 done2: 1042 return (error); 1043 } 1044 1045 #ifndef _SYS_SYSPROTO_H_ 1046 struct mlock_args { 1047 const void *addr; 1048 size_t len; 1049 }; 1050 #endif 1051 int 1052 sys_mlock(struct thread *td, struct mlock_args *uap) 1053 { 1054 1055 return (kern_mlock(td->td_proc, td->td_ucred, 1056 __DECONST(uintptr_t, uap->addr), uap->len)); 1057 } 1058 1059 int 1060 kern_mlock(struct proc *proc, struct ucred *cred, uintptr_t addr0, size_t len) 1061 { 1062 vm_offset_t addr, end, last, start; 1063 vm_size_t npages, size; 1064 vm_map_t map; 1065 unsigned long nsize; 1066 int error; 1067 1068 error = priv_check_cred(cred, PRIV_VM_MLOCK); 1069 if (error) 1070 return (error); 1071 addr = addr0; 1072 size = len; 1073 last = addr + size; 1074 start = trunc_page(addr); 1075 end = round_page(last); 1076 if (last < addr || end < addr) 1077 return (EINVAL); 1078 npages = atop(end - start); 1079 if (npages > vm_page_max_user_wired) 1080 return (ENOMEM); 1081 map = &proc->p_vmspace->vm_map; 1082 PROC_LOCK(proc); 1083 nsize = ptoa(npages + pmap_wired_count(map->pmap)); 1084 if (nsize > lim_cur_proc(proc, RLIMIT_MEMLOCK)) { 1085 PROC_UNLOCK(proc); 1086 return (ENOMEM); 1087 } 1088 PROC_UNLOCK(proc); 1089 #ifdef RACCT 1090 if (racct_enable) { 1091 PROC_LOCK(proc); 1092 error = racct_set(proc, RACCT_MEMLOCK, nsize); 1093 PROC_UNLOCK(proc); 1094 if (error != 0) 1095 return (ENOMEM); 1096 } 1097 #endif 1098 error = vm_map_wire(map, start, end, 1099 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); 1100 #ifdef RACCT 1101 if (racct_enable && error != KERN_SUCCESS) { 1102 PROC_LOCK(proc); 1103 racct_set(proc, RACCT_MEMLOCK, 1104 ptoa(pmap_wired_count(map->pmap))); 1105 PROC_UNLOCK(proc); 1106 } 1107 #endif 1108 switch (error) { 1109 case KERN_SUCCESS: 1110 return (0); 1111 case KERN_INVALID_ARGUMENT: 1112 return (EINVAL); 1113 default: 1114 return (ENOMEM); 1115 } 1116 } 1117 1118 #ifndef _SYS_SYSPROTO_H_ 1119 struct mlockall_args { 1120 int how; 1121 }; 1122 #endif 1123 1124 int 1125 sys_mlockall(struct thread *td, struct mlockall_args *uap) 1126 { 1127 vm_map_t map; 1128 int error; 1129 1130 map = &td->td_proc->p_vmspace->vm_map; 1131 error = priv_check(td, PRIV_VM_MLOCK); 1132 if (error) 1133 return (error); 1134 1135 if ((uap->how == 0) || ((uap->how & ~(MCL_CURRENT|MCL_FUTURE)) != 0)) 1136 return (EINVAL); 1137 1138 /* 1139 * If wiring all pages in the process would cause it to exceed 1140 * a hard resource limit, return ENOMEM. 1141 */ 1142 if (!old_mlock && uap->how & MCL_CURRENT) { 1143 if (map->size > lim_cur(td, RLIMIT_MEMLOCK)) 1144 return (ENOMEM); 1145 } 1146 #ifdef RACCT 1147 if (racct_enable) { 1148 PROC_LOCK(td->td_proc); 1149 error = racct_set(td->td_proc, RACCT_MEMLOCK, map->size); 1150 PROC_UNLOCK(td->td_proc); 1151 if (error != 0) 1152 return (ENOMEM); 1153 } 1154 #endif 1155 1156 if (uap->how & MCL_FUTURE) { 1157 vm_map_lock(map); 1158 vm_map_modflags(map, MAP_WIREFUTURE, 0); 1159 vm_map_unlock(map); 1160 error = 0; 1161 } 1162 1163 if (uap->how & MCL_CURRENT) { 1164 /* 1165 * P1003.1-2001 mandates that all currently mapped pages 1166 * will be memory resident and locked (wired) upon return 1167 * from mlockall(). vm_map_wire() will wire pages, by 1168 * calling vm_fault_wire() for each page in the region. 1169 */ 1170 error = vm_map_wire(map, vm_map_min(map), vm_map_max(map), 1171 VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); 1172 if (error == KERN_SUCCESS) 1173 error = 0; 1174 else if (error == KERN_RESOURCE_SHORTAGE) 1175 error = ENOMEM; 1176 else 1177 error = EAGAIN; 1178 } 1179 #ifdef RACCT 1180 if (racct_enable && error != KERN_SUCCESS) { 1181 PROC_LOCK(td->td_proc); 1182 racct_set(td->td_proc, RACCT_MEMLOCK, 1183 ptoa(pmap_wired_count(map->pmap))); 1184 PROC_UNLOCK(td->td_proc); 1185 } 1186 #endif 1187 1188 return (error); 1189 } 1190 1191 #ifndef _SYS_SYSPROTO_H_ 1192 struct munlockall_args { 1193 register_t dummy; 1194 }; 1195 #endif 1196 1197 int 1198 sys_munlockall(struct thread *td, struct munlockall_args *uap) 1199 { 1200 vm_map_t map; 1201 int error; 1202 1203 map = &td->td_proc->p_vmspace->vm_map; 1204 error = priv_check(td, PRIV_VM_MUNLOCK); 1205 if (error) 1206 return (error); 1207 1208 /* Clear the MAP_WIREFUTURE flag from this vm_map. */ 1209 vm_map_lock(map); 1210 vm_map_modflags(map, 0, MAP_WIREFUTURE); 1211 vm_map_unlock(map); 1212 1213 /* Forcibly unwire all pages. */ 1214 error = vm_map_unwire(map, vm_map_min(map), vm_map_max(map), 1215 VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); 1216 #ifdef RACCT 1217 if (racct_enable && error == KERN_SUCCESS) { 1218 PROC_LOCK(td->td_proc); 1219 racct_set(td->td_proc, RACCT_MEMLOCK, 0); 1220 PROC_UNLOCK(td->td_proc); 1221 } 1222 #endif 1223 1224 return (error); 1225 } 1226 1227 #ifndef _SYS_SYSPROTO_H_ 1228 struct munlock_args { 1229 const void *addr; 1230 size_t len; 1231 }; 1232 #endif 1233 int 1234 sys_munlock(struct thread *td, struct munlock_args *uap) 1235 { 1236 1237 return (kern_munlock(td, (uintptr_t)uap->addr, uap->len)); 1238 } 1239 1240 int 1241 kern_munlock(struct thread *td, uintptr_t addr0, size_t size) 1242 { 1243 vm_offset_t addr, end, last, start; 1244 #ifdef RACCT 1245 vm_map_t map; 1246 #endif 1247 int error; 1248 1249 error = priv_check(td, PRIV_VM_MUNLOCK); 1250 if (error) 1251 return (error); 1252 addr = addr0; 1253 last = addr + size; 1254 start = trunc_page(addr); 1255 end = round_page(last); 1256 if (last < addr || end < addr) 1257 return (EINVAL); 1258 error = vm_map_unwire(&td->td_proc->p_vmspace->vm_map, start, end, 1259 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); 1260 #ifdef RACCT 1261 if (racct_enable && error == KERN_SUCCESS) { 1262 PROC_LOCK(td->td_proc); 1263 map = &td->td_proc->p_vmspace->vm_map; 1264 racct_set(td->td_proc, RACCT_MEMLOCK, 1265 ptoa(pmap_wired_count(map->pmap))); 1266 PROC_UNLOCK(td->td_proc); 1267 } 1268 #endif 1269 return (error == KERN_SUCCESS ? 0 : ENOMEM); 1270 } 1271 1272 /* 1273 * vm_mmap_vnode() 1274 * 1275 * Helper function for vm_mmap. Perform sanity check specific for mmap 1276 * operations on vnodes. 1277 */ 1278 int 1279 vm_mmap_vnode(struct thread *td, vm_size_t objsize, 1280 vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, 1281 struct vnode *vp, vm_ooffset_t *foffp, vm_object_t *objp, 1282 boolean_t *writecounted) 1283 { 1284 struct vattr va; 1285 vm_object_t obj; 1286 vm_ooffset_t foff; 1287 struct ucred *cred; 1288 int error, flags; 1289 bool writex; 1290 1291 cred = td->td_ucred; 1292 writex = (*maxprotp & VM_PROT_WRITE) != 0 && 1293 (*flagsp & MAP_SHARED) != 0; 1294 if ((error = vget(vp, LK_SHARED)) != 0) 1295 return (error); 1296 AUDIT_ARG_VNODE1(vp); 1297 foff = *foffp; 1298 flags = *flagsp; 1299 obj = vp->v_object; 1300 if (vp->v_type == VREG) { 1301 /* 1302 * Get the proper underlying object 1303 */ 1304 if (obj == NULL) { 1305 error = EINVAL; 1306 goto done; 1307 } 1308 if (obj->type == OBJT_VNODE && obj->handle != vp) { 1309 vput(vp); 1310 vp = (struct vnode *)obj->handle; 1311 /* 1312 * Bypass filesystems obey the mpsafety of the 1313 * underlying fs. Tmpfs never bypasses. 1314 */ 1315 error = vget(vp, LK_SHARED); 1316 if (error != 0) 1317 return (error); 1318 } 1319 if (writex) { 1320 *writecounted = TRUE; 1321 vm_pager_update_writecount(obj, 0, objsize); 1322 } 1323 } else { 1324 error = EINVAL; 1325 goto done; 1326 } 1327 if ((error = VOP_GETATTR(vp, &va, cred))) 1328 goto done; 1329 #ifdef MAC 1330 /* This relies on VM_PROT_* matching PROT_*. */ 1331 error = mac_vnode_check_mmap(cred, vp, (int)prot, flags); 1332 if (error != 0) 1333 goto done; 1334 #endif 1335 if ((flags & MAP_SHARED) != 0) { 1336 if ((va.va_flags & (SF_SNAPSHOT|IMMUTABLE|APPEND)) != 0) { 1337 if (prot & VM_PROT_WRITE) { 1338 error = EPERM; 1339 goto done; 1340 } 1341 *maxprotp &= ~VM_PROT_WRITE; 1342 } 1343 } 1344 /* 1345 * If it is a regular file without any references 1346 * we do not need to sync it. 1347 * Adjust object size to be the size of actual file. 1348 */ 1349 objsize = round_page(va.va_size); 1350 if (va.va_nlink == 0) 1351 flags |= MAP_NOSYNC; 1352 if (obj->type == OBJT_VNODE) { 1353 obj = vm_pager_allocate(OBJT_VNODE, vp, objsize, prot, foff, 1354 cred); 1355 if (obj == NULL) { 1356 error = ENOMEM; 1357 goto done; 1358 } 1359 } else { 1360 KASSERT(obj->type == OBJT_DEFAULT || 1361 (obj->flags & OBJ_SWAP) != 0, 1362 ("wrong object type")); 1363 vm_object_reference(obj); 1364 #if VM_NRESERVLEVEL > 0 1365 if ((obj->flags & OBJ_COLORED) == 0) { 1366 VM_OBJECT_WLOCK(obj); 1367 vm_object_color(obj, 0); 1368 VM_OBJECT_WUNLOCK(obj); 1369 } 1370 #endif 1371 } 1372 *objp = obj; 1373 *flagsp = flags; 1374 1375 VOP_MMAPPED(vp); 1376 1377 done: 1378 if (error != 0 && *writecounted) { 1379 *writecounted = FALSE; 1380 vm_pager_update_writecount(obj, objsize, 0); 1381 } 1382 vput(vp); 1383 return (error); 1384 } 1385 1386 /* 1387 * vm_mmap_cdev() 1388 * 1389 * Helper function for vm_mmap. Perform sanity check specific for mmap 1390 * operations on cdevs. 1391 */ 1392 int 1393 vm_mmap_cdev(struct thread *td, vm_size_t objsize, vm_prot_t prot, 1394 vm_prot_t *maxprotp, int *flagsp, struct cdev *cdev, struct cdevsw *dsw, 1395 vm_ooffset_t *foff, vm_object_t *objp) 1396 { 1397 vm_object_t obj; 1398 int error, flags; 1399 1400 flags = *flagsp; 1401 1402 if (dsw->d_flags & D_MMAP_ANON) { 1403 *objp = NULL; 1404 *foff = 0; 1405 *maxprotp = VM_PROT_ALL; 1406 *flagsp |= MAP_ANON; 1407 return (0); 1408 } 1409 /* 1410 * cdevs do not provide private mappings of any kind. 1411 */ 1412 if ((*maxprotp & VM_PROT_WRITE) == 0 && 1413 (prot & VM_PROT_WRITE) != 0) 1414 return (EACCES); 1415 if (flags & (MAP_PRIVATE|MAP_COPY)) 1416 return (EINVAL); 1417 /* 1418 * Force device mappings to be shared. 1419 */ 1420 flags |= MAP_SHARED; 1421 #ifdef MAC_XXX 1422 error = mac_cdev_check_mmap(td->td_ucred, cdev, (int)prot); 1423 if (error != 0) 1424 return (error); 1425 #endif 1426 /* 1427 * First, try d_mmap_single(). If that is not implemented 1428 * (returns ENODEV), fall back to using the device pager. 1429 * Note that d_mmap_single() must return a reference to the 1430 * object (it needs to bump the reference count of the object 1431 * it returns somehow). 1432 * 1433 * XXX assumes VM_PROT_* == PROT_* 1434 */ 1435 error = dsw->d_mmap_single(cdev, foff, objsize, objp, (int)prot); 1436 if (error != ENODEV) 1437 return (error); 1438 obj = vm_pager_allocate(OBJT_DEVICE, cdev, objsize, prot, *foff, 1439 td->td_ucred); 1440 if (obj == NULL) 1441 return (EINVAL); 1442 *objp = obj; 1443 *flagsp = flags; 1444 return (0); 1445 } 1446 1447 /* 1448 * vm_mmap() 1449 * 1450 * Internal version of mmap used by exec, sys5 shared memory, and 1451 * various device drivers. Handle is either a vnode pointer, a 1452 * character device, or NULL for MAP_ANON. 1453 */ 1454 int 1455 vm_mmap(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, 1456 vm_prot_t maxprot, int flags, 1457 objtype_t handle_type, void *handle, 1458 vm_ooffset_t foff) 1459 { 1460 vm_object_t object; 1461 struct thread *td = curthread; 1462 int error; 1463 boolean_t writecounted; 1464 1465 if (size == 0) 1466 return (EINVAL); 1467 1468 size = round_page(size); 1469 object = NULL; 1470 writecounted = FALSE; 1471 1472 /* 1473 * Lookup/allocate object. 1474 */ 1475 switch (handle_type) { 1476 case OBJT_DEVICE: { 1477 struct cdevsw *dsw; 1478 struct cdev *cdev; 1479 int ref; 1480 1481 cdev = handle; 1482 dsw = dev_refthread(cdev, &ref); 1483 if (dsw == NULL) 1484 return (ENXIO); 1485 error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, cdev, 1486 dsw, &foff, &object); 1487 dev_relthread(cdev, ref); 1488 break; 1489 } 1490 case OBJT_VNODE: 1491 error = vm_mmap_vnode(td, size, prot, &maxprot, &flags, 1492 handle, &foff, &object, &writecounted); 1493 break; 1494 case OBJT_DEFAULT: 1495 if (handle == NULL) { 1496 error = 0; 1497 break; 1498 } 1499 /* FALLTHROUGH */ 1500 default: 1501 error = EINVAL; 1502 break; 1503 } 1504 if (error) 1505 return (error); 1506 1507 error = vm_mmap_object(map, addr, size, prot, maxprot, flags, object, 1508 foff, writecounted, td); 1509 if (error != 0 && object != NULL) { 1510 /* 1511 * If this mapping was accounted for in the vnode's 1512 * writecount, then undo that now. 1513 */ 1514 if (writecounted) 1515 vm_pager_release_writecount(object, 0, size); 1516 vm_object_deallocate(object); 1517 } 1518 return (error); 1519 } 1520 1521 int 1522 kern_mmap_racct_check(struct thread *td, vm_map_t map, vm_size_t size) 1523 { 1524 int error; 1525 1526 RACCT_PROC_LOCK(td->td_proc); 1527 if (map->size + size > lim_cur(td, RLIMIT_VMEM)) { 1528 RACCT_PROC_UNLOCK(td->td_proc); 1529 return (ENOMEM); 1530 } 1531 if (racct_set(td->td_proc, RACCT_VMEM, map->size + size)) { 1532 RACCT_PROC_UNLOCK(td->td_proc); 1533 return (ENOMEM); 1534 } 1535 if (!old_mlock && map->flags & MAP_WIREFUTURE) { 1536 if (ptoa(pmap_wired_count(map->pmap)) + size > 1537 lim_cur(td, RLIMIT_MEMLOCK)) { 1538 racct_set_force(td->td_proc, RACCT_VMEM, map->size); 1539 RACCT_PROC_UNLOCK(td->td_proc); 1540 return (ENOMEM); 1541 } 1542 error = racct_set(td->td_proc, RACCT_MEMLOCK, 1543 ptoa(pmap_wired_count(map->pmap)) + size); 1544 if (error != 0) { 1545 racct_set_force(td->td_proc, RACCT_VMEM, map->size); 1546 RACCT_PROC_UNLOCK(td->td_proc); 1547 return (error); 1548 } 1549 } 1550 RACCT_PROC_UNLOCK(td->td_proc); 1551 return (0); 1552 } 1553 1554 /* 1555 * Internal version of mmap that maps a specific VM object into an 1556 * map. Called by mmap for MAP_ANON, vm_mmap, shm_mmap, and vn_mmap. 1557 */ 1558 int 1559 vm_mmap_object(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, 1560 vm_prot_t maxprot, int flags, vm_object_t object, vm_ooffset_t foff, 1561 boolean_t writecounted, struct thread *td) 1562 { 1563 vm_offset_t max_addr; 1564 int docow, error, findspace, rv; 1565 bool curmap, fitit; 1566 1567 curmap = map == &td->td_proc->p_vmspace->vm_map; 1568 if (curmap) { 1569 error = kern_mmap_racct_check(td, map, size); 1570 if (error != 0) 1571 return (error); 1572 } 1573 1574 /* 1575 * We currently can only deal with page aligned file offsets. 1576 * The mmap() system call already enforces this by subtracting 1577 * the page offset from the file offset, but checking here 1578 * catches errors in device drivers (e.g. d_single_mmap() 1579 * callbacks) and other internal mapping requests (such as in 1580 * exec). 1581 */ 1582 if (foff & PAGE_MASK) 1583 return (EINVAL); 1584 1585 if ((flags & MAP_FIXED) == 0) { 1586 fitit = TRUE; 1587 *addr = round_page(*addr); 1588 } else { 1589 if (*addr != trunc_page(*addr)) 1590 return (EINVAL); 1591 fitit = FALSE; 1592 } 1593 1594 if (flags & MAP_ANON) { 1595 if (object != NULL || foff != 0) 1596 return (EINVAL); 1597 docow = 0; 1598 } else if (flags & MAP_PREFAULT_READ) 1599 docow = MAP_PREFAULT; 1600 else 1601 docow = MAP_PREFAULT_PARTIAL; 1602 1603 if ((flags & (MAP_ANON|MAP_SHARED)) == 0) 1604 docow |= MAP_COPY_ON_WRITE; 1605 if (flags & MAP_NOSYNC) 1606 docow |= MAP_DISABLE_SYNCER; 1607 if (flags & MAP_NOCORE) 1608 docow |= MAP_DISABLE_COREDUMP; 1609 /* Shared memory is also shared with children. */ 1610 if (flags & MAP_SHARED) 1611 docow |= MAP_INHERIT_SHARE; 1612 if (writecounted) 1613 docow |= MAP_WRITECOUNT; 1614 if (flags & MAP_STACK) { 1615 if (object != NULL) 1616 return (EINVAL); 1617 docow |= MAP_STACK_GROWS_DOWN; 1618 } 1619 if ((flags & MAP_EXCL) != 0) 1620 docow |= MAP_CHECK_EXCL; 1621 if ((flags & MAP_GUARD) != 0) 1622 docow |= MAP_CREATE_GUARD; 1623 1624 if (fitit) { 1625 if ((flags & MAP_ALIGNMENT_MASK) == MAP_ALIGNED_SUPER) 1626 findspace = VMFS_SUPER_SPACE; 1627 else if ((flags & MAP_ALIGNMENT_MASK) != 0) 1628 findspace = VMFS_ALIGNED_SPACE(flags >> 1629 MAP_ALIGNMENT_SHIFT); 1630 else 1631 findspace = VMFS_OPTIMAL_SPACE; 1632 max_addr = 0; 1633 #ifdef MAP_32BIT 1634 if ((flags & MAP_32BIT) != 0) 1635 max_addr = MAP_32BIT_MAX_ADDR; 1636 #endif 1637 if (curmap) { 1638 rv = vm_map_find_min(map, object, foff, addr, size, 1639 round_page((vm_offset_t)td->td_proc->p_vmspace-> 1640 vm_daddr + lim_max(td, RLIMIT_DATA)), max_addr, 1641 findspace, prot, maxprot, docow); 1642 } else { 1643 rv = vm_map_find(map, object, foff, addr, size, 1644 max_addr, findspace, prot, maxprot, docow); 1645 } 1646 } else { 1647 rv = vm_map_fixed(map, object, foff, *addr, size, 1648 prot, maxprot, docow); 1649 } 1650 1651 if (rv == KERN_SUCCESS) { 1652 /* 1653 * If the process has requested that all future mappings 1654 * be wired, then heed this. 1655 */ 1656 if ((map->flags & MAP_WIREFUTURE) != 0) { 1657 vm_map_lock(map); 1658 if ((map->flags & MAP_WIREFUTURE) != 0) 1659 (void)vm_map_wire_locked(map, *addr, 1660 *addr + size, VM_MAP_WIRE_USER | 1661 ((flags & MAP_STACK) ? VM_MAP_WIRE_HOLESOK : 1662 VM_MAP_WIRE_NOHOLES)); 1663 vm_map_unlock(map); 1664 } 1665 } 1666 return (vm_mmap_to_errno(rv)); 1667 } 1668 1669 /* 1670 * Translate a Mach VM return code to zero on success or the appropriate errno 1671 * on failure. 1672 */ 1673 int 1674 vm_mmap_to_errno(int rv) 1675 { 1676 1677 switch (rv) { 1678 case KERN_SUCCESS: 1679 return (0); 1680 case KERN_INVALID_ADDRESS: 1681 case KERN_NO_SPACE: 1682 return (ENOMEM); 1683 case KERN_PROTECTION_FAILURE: 1684 return (EACCES); 1685 default: 1686 return (EINVAL); 1687 } 1688 } 1689