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 #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 struct mmap_req mr = { 203 .mr_hint = addr0, 204 .mr_len = len, 205 .mr_prot = prot, 206 .mr_flags = flags, 207 .mr_fd = fd, 208 .mr_pos = pos 209 }; 210 211 return (kern_mmap_req(td, &mr)); 212 } 213 214 int 215 kern_mmap_req(struct thread *td, const struct mmap_req *mrp) 216 { 217 struct vmspace *vms; 218 struct file *fp; 219 struct proc *p; 220 off_t pos; 221 vm_offset_t addr; 222 vm_size_t len, pageoff, size; 223 vm_prot_t cap_maxprot; 224 int align, error, fd, flags, max_prot, prot; 225 cap_rights_t rights; 226 mmap_check_fp_fn check_fp_fn; 227 228 addr = mrp->mr_hint; 229 len = mrp->mr_len; 230 prot = mrp->mr_prot; 231 flags = mrp->mr_flags; 232 fd = mrp->mr_fd; 233 pos = mrp->mr_pos; 234 check_fp_fn = mrp->mr_check_fp_fn; 235 236 if ((prot & ~(_PROT_ALL | PROT_MAX(_PROT_ALL))) != 0) 237 return (EINVAL); 238 max_prot = PROT_MAX_EXTRACT(prot); 239 prot = PROT_EXTRACT(prot); 240 if (max_prot != 0 && (max_prot & prot) != prot) 241 return (ENOTSUP); 242 243 p = td->td_proc; 244 245 /* 246 * Always honor PROT_MAX if set. If not, default to all 247 * permissions unless we're implying maximum permissions. 248 */ 249 if (max_prot == 0) 250 max_prot = kern_mmap_maxprot(p, prot); 251 252 vms = p->p_vmspace; 253 fp = NULL; 254 AUDIT_ARG_FD(fd); 255 256 /* 257 * Ignore old flags that used to be defined but did not do anything. 258 */ 259 flags &= ~(MAP_RESERVED0020 | MAP_RESERVED0040); 260 261 /* 262 * Enforce the constraints. 263 * Mapping of length 0 is only allowed for old binaries. 264 * Anonymous mapping shall specify -1 as filedescriptor and 265 * zero position for new code. Be nice to ancient a.out 266 * binaries and correct pos for anonymous mapping, since old 267 * ld.so sometimes issues anonymous map requests with non-zero 268 * pos. 269 */ 270 if (!SV_CURPROC_FLAG(SV_AOUT)) { 271 if ((len == 0 && p->p_osrel >= P_OSREL_MAP_ANON) || 272 ((flags & MAP_ANON) != 0 && (fd != -1 || pos != 0))) 273 return (EINVAL); 274 } else { 275 if ((flags & MAP_ANON) != 0) 276 pos = 0; 277 } 278 279 if (flags & MAP_STACK) { 280 if ((fd != -1) || 281 ((prot & (PROT_READ | PROT_WRITE)) != (PROT_READ | PROT_WRITE))) 282 return (EINVAL); 283 flags |= MAP_ANON; 284 pos = 0; 285 } 286 if ((flags & ~(MAP_SHARED | MAP_PRIVATE | MAP_FIXED | MAP_HASSEMAPHORE | 287 MAP_STACK | MAP_NOSYNC | MAP_ANON | MAP_EXCL | MAP_NOCORE | 288 MAP_PREFAULT_READ | MAP_GUARD | 289 #ifdef MAP_32BIT 290 MAP_32BIT | 291 #endif 292 MAP_ALIGNMENT_MASK)) != 0) 293 return (EINVAL); 294 if ((flags & (MAP_EXCL | MAP_FIXED)) == MAP_EXCL) 295 return (EINVAL); 296 if ((flags & (MAP_SHARED | MAP_PRIVATE)) == (MAP_SHARED | MAP_PRIVATE)) 297 return (EINVAL); 298 if (prot != PROT_NONE && 299 (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC)) != 0) 300 return (EINVAL); 301 if ((flags & MAP_GUARD) != 0 && (prot != PROT_NONE || fd != -1 || 302 pos != 0 || (flags & ~(MAP_FIXED | MAP_GUARD | MAP_EXCL | 303 #ifdef MAP_32BIT 304 MAP_32BIT | 305 #endif 306 MAP_ALIGNMENT_MASK)) != 0)) 307 return (EINVAL); 308 309 /* 310 * Align the file position to a page boundary, 311 * and save its page offset component. 312 */ 313 pageoff = (pos & PAGE_MASK); 314 pos -= pageoff; 315 316 /* Compute size from len by rounding (on both ends). */ 317 size = len + pageoff; /* low end... */ 318 size = round_page(size); /* hi end */ 319 /* Check for rounding up to zero. */ 320 if (len > size) 321 return (ENOMEM); 322 323 /* Ensure alignment is at least a page and fits in a pointer. */ 324 align = flags & MAP_ALIGNMENT_MASK; 325 if (align != 0 && align != MAP_ALIGNED_SUPER && 326 (align >> MAP_ALIGNMENT_SHIFT >= sizeof(void *) * NBBY || 327 align >> MAP_ALIGNMENT_SHIFT < PAGE_SHIFT)) 328 return (EINVAL); 329 330 /* 331 * Check for illegal addresses. Watch out for address wrap... Note 332 * that VM_*_ADDRESS are not constants due to casts (argh). 333 */ 334 if (flags & MAP_FIXED) { 335 /* 336 * The specified address must have the same remainder 337 * as the file offset taken modulo PAGE_SIZE, so it 338 * should be aligned after adjustment by pageoff. 339 */ 340 addr -= pageoff; 341 if (addr & PAGE_MASK) 342 return (EINVAL); 343 344 /* Address range must be all in user VM space. */ 345 if (!vm_map_range_valid(&vms->vm_map, addr, addr + size)) 346 return (EINVAL); 347 #ifdef MAP_32BIT 348 if (flags & MAP_32BIT && addr + size > MAP_32BIT_MAX_ADDR) 349 return (EINVAL); 350 } else if (flags & MAP_32BIT) { 351 /* 352 * For MAP_32BIT, override the hint if it is too high and 353 * do not bother moving the mapping past the heap (since 354 * the heap is usually above 2GB). 355 */ 356 if (addr + size > MAP_32BIT_MAX_ADDR) 357 addr = 0; 358 #endif 359 } else { 360 /* 361 * XXX for non-fixed mappings where no hint is provided or 362 * the hint would fall in the potential heap space, 363 * place it after the end of the largest possible heap. 364 * 365 * There should really be a pmap call to determine a reasonable 366 * location. 367 */ 368 if (addr == 0 || 369 (addr >= round_page((vm_offset_t)vms->vm_taddr) && 370 addr < round_page((vm_offset_t)vms->vm_daddr + 371 lim_max(td, RLIMIT_DATA)))) 372 addr = round_page((vm_offset_t)vms->vm_daddr + 373 lim_max(td, RLIMIT_DATA)); 374 } 375 if (len == 0) { 376 /* 377 * Return success without mapping anything for old 378 * binaries that request a page-aligned mapping of 379 * length 0. For modern binaries, this function 380 * returns an error earlier. 381 */ 382 error = 0; 383 } else if ((flags & MAP_GUARD) != 0) { 384 error = vm_mmap_object(&vms->vm_map, &addr, size, VM_PROT_NONE, 385 VM_PROT_NONE, flags, NULL, pos, FALSE, td); 386 } else if ((flags & MAP_ANON) != 0) { 387 /* 388 * Mapping blank space is trivial. 389 * 390 * This relies on VM_PROT_* matching PROT_*. 391 */ 392 error = vm_mmap_object(&vms->vm_map, &addr, size, prot, 393 max_prot, flags, NULL, pos, FALSE, td); 394 } else { 395 /* 396 * Mapping file, get fp for validation and don't let the 397 * descriptor disappear on us if we block. Check capability 398 * rights, but also return the maximum rights to be combined 399 * with maxprot later. 400 */ 401 cap_rights_init_one(&rights, CAP_MMAP); 402 if (prot & PROT_READ) 403 cap_rights_set_one(&rights, CAP_MMAP_R); 404 if ((flags & MAP_SHARED) != 0) { 405 if (prot & PROT_WRITE) 406 cap_rights_set_one(&rights, CAP_MMAP_W); 407 } 408 if (prot & PROT_EXEC) 409 cap_rights_set_one(&rights, CAP_MMAP_X); 410 error = fget_mmap(td, fd, &rights, &cap_maxprot, &fp); 411 if (error != 0) 412 goto done; 413 if ((flags & (MAP_SHARED | MAP_PRIVATE)) == 0 && 414 p->p_osrel >= P_OSREL_MAP_FSTRICT) { 415 error = EINVAL; 416 goto done; 417 } 418 if (check_fp_fn != NULL) { 419 error = check_fp_fn(fp, prot, max_prot & cap_maxprot, 420 flags); 421 if (error != 0) 422 goto done; 423 } 424 /* This relies on VM_PROT_* matching PROT_*. */ 425 error = fo_mmap(fp, &vms->vm_map, &addr, size, prot, 426 max_prot & cap_maxprot, flags, pos, td); 427 } 428 429 if (error == 0) 430 td->td_retval[0] = (register_t) (addr + pageoff); 431 done: 432 if (fp) 433 fdrop(fp, td); 434 435 return (error); 436 } 437 438 #if defined(COMPAT_FREEBSD6) 439 int 440 freebsd6_mmap(struct thread *td, struct freebsd6_mmap_args *uap) 441 { 442 443 return (kern_mmap(td, (uintptr_t)uap->addr, uap->len, uap->prot, 444 uap->flags, uap->fd, uap->pos)); 445 } 446 #endif 447 448 #ifdef COMPAT_43 449 #ifndef _SYS_SYSPROTO_H_ 450 struct ommap_args { 451 caddr_t addr; 452 int len; 453 int prot; 454 int flags; 455 int fd; 456 long pos; 457 }; 458 #endif 459 int 460 ommap(struct thread *td, struct ommap_args *uap) 461 { 462 static const char cvtbsdprot[8] = { 463 0, 464 PROT_EXEC, 465 PROT_WRITE, 466 PROT_EXEC | PROT_WRITE, 467 PROT_READ, 468 PROT_EXEC | PROT_READ, 469 PROT_WRITE | PROT_READ, 470 PROT_EXEC | PROT_WRITE | PROT_READ, 471 }; 472 int flags, prot; 473 474 #define OMAP_ANON 0x0002 475 #define OMAP_COPY 0x0020 476 #define OMAP_SHARED 0x0010 477 #define OMAP_FIXED 0x0100 478 479 prot = cvtbsdprot[uap->prot & 0x7]; 480 #if (defined(COMPAT_FREEBSD32) && defined(__amd64__)) || defined(__i386__) 481 if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32) && 482 prot != 0) 483 prot |= PROT_EXEC; 484 #endif 485 flags = 0; 486 if (uap->flags & OMAP_ANON) 487 flags |= MAP_ANON; 488 if (uap->flags & OMAP_COPY) 489 flags |= MAP_COPY; 490 if (uap->flags & OMAP_SHARED) 491 flags |= MAP_SHARED; 492 else 493 flags |= MAP_PRIVATE; 494 if (uap->flags & OMAP_FIXED) 495 flags |= MAP_FIXED; 496 return (kern_mmap(td, (uintptr_t)uap->addr, uap->len, prot, flags, 497 uap->fd, uap->pos)); 498 } 499 #endif /* COMPAT_43 */ 500 501 502 #ifndef _SYS_SYSPROTO_H_ 503 struct msync_args { 504 void *addr; 505 size_t len; 506 int flags; 507 }; 508 #endif 509 int 510 sys_msync(struct thread *td, struct msync_args *uap) 511 { 512 513 return (kern_msync(td, (uintptr_t)uap->addr, uap->len, uap->flags)); 514 } 515 516 int 517 kern_msync(struct thread *td, uintptr_t addr0, size_t size, int flags) 518 { 519 vm_offset_t addr; 520 vm_size_t pageoff; 521 vm_map_t map; 522 int rv; 523 524 addr = addr0; 525 pageoff = (addr & PAGE_MASK); 526 addr -= pageoff; 527 size += pageoff; 528 size = (vm_size_t) round_page(size); 529 if (addr + size < addr) 530 return (EINVAL); 531 532 if ((flags & (MS_ASYNC|MS_INVALIDATE)) == (MS_ASYNC|MS_INVALIDATE)) 533 return (EINVAL); 534 535 map = &td->td_proc->p_vmspace->vm_map; 536 537 /* 538 * Clean the pages and interpret the return value. 539 */ 540 rv = vm_map_sync(map, addr, addr + size, (flags & MS_ASYNC) == 0, 541 (flags & MS_INVALIDATE) != 0); 542 switch (rv) { 543 case KERN_SUCCESS: 544 return (0); 545 case KERN_INVALID_ADDRESS: 546 return (ENOMEM); 547 case KERN_INVALID_ARGUMENT: 548 return (EBUSY); 549 case KERN_FAILURE: 550 return (EIO); 551 default: 552 return (EINVAL); 553 } 554 } 555 556 #ifndef _SYS_SYSPROTO_H_ 557 struct munmap_args { 558 void *addr; 559 size_t len; 560 }; 561 #endif 562 int 563 sys_munmap(struct thread *td, struct munmap_args *uap) 564 { 565 566 return (kern_munmap(td, (uintptr_t)uap->addr, uap->len)); 567 } 568 569 int 570 kern_munmap(struct thread *td, uintptr_t addr0, size_t size) 571 { 572 #ifdef HWPMC_HOOKS 573 struct pmckern_map_out pkm; 574 vm_map_entry_t entry; 575 bool pmc_handled; 576 #endif 577 vm_offset_t addr, end; 578 vm_size_t pageoff; 579 vm_map_t map; 580 581 if (size == 0) 582 return (EINVAL); 583 584 addr = addr0; 585 pageoff = (addr & PAGE_MASK); 586 addr -= pageoff; 587 size += pageoff; 588 size = (vm_size_t) round_page(size); 589 end = addr + size; 590 map = &td->td_proc->p_vmspace->vm_map; 591 if (!vm_map_range_valid(map, addr, end)) 592 return (EINVAL); 593 594 vm_map_lock(map); 595 #ifdef HWPMC_HOOKS 596 pmc_handled = false; 597 if (PMC_HOOK_INSTALLED(PMC_FN_MUNMAP)) { 598 pmc_handled = true; 599 /* 600 * Inform hwpmc if the address range being unmapped contains 601 * an executable region. 602 */ 603 pkm.pm_address = (uintptr_t) NULL; 604 if (vm_map_lookup_entry(map, addr, &entry)) { 605 for (; entry->start < end; 606 entry = vm_map_entry_succ(entry)) { 607 if (vm_map_check_protection(map, entry->start, 608 entry->end, VM_PROT_EXECUTE) == TRUE) { 609 pkm.pm_address = (uintptr_t) addr; 610 pkm.pm_size = (size_t) size; 611 break; 612 } 613 } 614 } 615 } 616 #endif 617 vm_map_delete(map, addr, end); 618 619 #ifdef HWPMC_HOOKS 620 if (__predict_false(pmc_handled)) { 621 /* downgrade the lock to prevent a LOR with the pmc-sx lock */ 622 vm_map_lock_downgrade(map); 623 if (pkm.pm_address != (uintptr_t) NULL) 624 PMC_CALL_HOOK(td, PMC_FN_MUNMAP, (void *) &pkm); 625 vm_map_unlock_read(map); 626 } else 627 #endif 628 vm_map_unlock(map); 629 630 /* vm_map_delete returns nothing but KERN_SUCCESS anyway */ 631 return (0); 632 } 633 634 #ifndef _SYS_SYSPROTO_H_ 635 struct mprotect_args { 636 const void *addr; 637 size_t len; 638 int prot; 639 }; 640 #endif 641 int 642 sys_mprotect(struct thread *td, struct mprotect_args *uap) 643 { 644 645 return (kern_mprotect(td, (uintptr_t)uap->addr, uap->len, uap->prot)); 646 } 647 648 int 649 kern_mprotect(struct thread *td, uintptr_t addr0, size_t size, int prot) 650 { 651 vm_offset_t addr; 652 vm_size_t pageoff; 653 int vm_error, max_prot; 654 655 addr = addr0; 656 if ((prot & ~(_PROT_ALL | PROT_MAX(_PROT_ALL))) != 0) 657 return (EINVAL); 658 max_prot = PROT_MAX_EXTRACT(prot); 659 prot = PROT_EXTRACT(prot); 660 pageoff = (addr & PAGE_MASK); 661 addr -= pageoff; 662 size += pageoff; 663 size = (vm_size_t) round_page(size); 664 #ifdef COMPAT_FREEBSD32 665 if (SV_PROC_FLAG(td->td_proc, SV_ILP32)) { 666 if (((addr + size) & 0xffffffff) < addr) 667 return (EINVAL); 668 } else 669 #endif 670 if (addr + size < addr) 671 return (EINVAL); 672 673 vm_error = KERN_SUCCESS; 674 if (max_prot != 0) { 675 if ((max_prot & prot) != prot) 676 return (ENOTSUP); 677 vm_error = vm_map_protect(&td->td_proc->p_vmspace->vm_map, 678 addr, addr + size, max_prot, TRUE); 679 } 680 if (vm_error == KERN_SUCCESS) 681 vm_error = vm_map_protect(&td->td_proc->p_vmspace->vm_map, 682 addr, addr + size, prot, FALSE); 683 684 switch (vm_error) { 685 case KERN_SUCCESS: 686 return (0); 687 case KERN_PROTECTION_FAILURE: 688 return (EACCES); 689 case KERN_RESOURCE_SHORTAGE: 690 return (ENOMEM); 691 } 692 return (EINVAL); 693 } 694 695 #ifndef _SYS_SYSPROTO_H_ 696 struct minherit_args { 697 void *addr; 698 size_t len; 699 int inherit; 700 }; 701 #endif 702 int 703 sys_minherit(struct thread *td, struct minherit_args *uap) 704 { 705 706 return (kern_minherit(td, (uintptr_t)uap->addr, uap->len, 707 uap->inherit)); 708 } 709 710 int 711 kern_minherit(struct thread *td, uintptr_t addr0, size_t len, int inherit0) 712 { 713 vm_offset_t addr; 714 vm_size_t size, pageoff; 715 vm_inherit_t inherit; 716 717 addr = (vm_offset_t)addr0; 718 size = len; 719 inherit = inherit0; 720 721 pageoff = (addr & PAGE_MASK); 722 addr -= pageoff; 723 size += pageoff; 724 size = (vm_size_t) round_page(size); 725 if (addr + size < addr) 726 return (EINVAL); 727 728 switch (vm_map_inherit(&td->td_proc->p_vmspace->vm_map, addr, 729 addr + size, inherit)) { 730 case KERN_SUCCESS: 731 return (0); 732 case KERN_PROTECTION_FAILURE: 733 return (EACCES); 734 } 735 return (EINVAL); 736 } 737 738 #ifndef _SYS_SYSPROTO_H_ 739 struct madvise_args { 740 void *addr; 741 size_t len; 742 int behav; 743 }; 744 #endif 745 746 int 747 sys_madvise(struct thread *td, struct madvise_args *uap) 748 { 749 750 return (kern_madvise(td, (uintptr_t)uap->addr, uap->len, uap->behav)); 751 } 752 753 int 754 kern_madvise(struct thread *td, uintptr_t addr0, size_t len, int behav) 755 { 756 vm_map_t map; 757 vm_offset_t addr, end, start; 758 int flags; 759 760 /* 761 * Check for our special case, advising the swap pager we are 762 * "immortal." 763 */ 764 if (behav == MADV_PROTECT) { 765 flags = PPROT_SET; 766 return (kern_procctl(td, P_PID, td->td_proc->p_pid, 767 PROC_SPROTECT, &flags)); 768 } 769 770 /* 771 * Check for illegal addresses. Watch out for address wrap... Note 772 * that VM_*_ADDRESS are not constants due to casts (argh). 773 */ 774 map = &td->td_proc->p_vmspace->vm_map; 775 addr = addr0; 776 if (!vm_map_range_valid(map, addr, addr + len)) 777 return (EINVAL); 778 779 /* 780 * Since this routine is only advisory, we default to conservative 781 * behavior. 782 */ 783 start = trunc_page(addr); 784 end = round_page(addr + len); 785 786 /* 787 * vm_map_madvise() checks for illegal values of behav. 788 */ 789 return (vm_map_madvise(map, start, end, behav)); 790 } 791 792 #ifndef _SYS_SYSPROTO_H_ 793 struct mincore_args { 794 const void *addr; 795 size_t len; 796 char *vec; 797 }; 798 #endif 799 800 int 801 sys_mincore(struct thread *td, struct mincore_args *uap) 802 { 803 804 return (kern_mincore(td, (uintptr_t)uap->addr, uap->len, uap->vec)); 805 } 806 807 int 808 kern_mincore(struct thread *td, uintptr_t addr0, size_t len, char *vec) 809 { 810 pmap_t pmap; 811 vm_map_t map; 812 vm_map_entry_t current, entry; 813 vm_object_t object; 814 vm_offset_t addr, cend, end, first_addr; 815 vm_paddr_t pa; 816 vm_page_t m; 817 vm_pindex_t pindex; 818 int error, lastvecindex, mincoreinfo, vecindex; 819 unsigned int timestamp; 820 821 /* 822 * Make sure that the addresses presented are valid for user 823 * mode. 824 */ 825 first_addr = addr = trunc_page(addr0); 826 end = round_page(addr0 + len); 827 map = &td->td_proc->p_vmspace->vm_map; 828 if (end > vm_map_max(map) || end < addr) 829 return (ENOMEM); 830 831 pmap = vmspace_pmap(td->td_proc->p_vmspace); 832 833 vm_map_lock_read(map); 834 RestartScan: 835 timestamp = map->timestamp; 836 837 if (!vm_map_lookup_entry(map, addr, &entry)) { 838 vm_map_unlock_read(map); 839 return (ENOMEM); 840 } 841 842 /* 843 * Do this on a map entry basis so that if the pages are not 844 * in the current processes address space, we can easily look 845 * up the pages elsewhere. 846 */ 847 lastvecindex = -1; 848 while (entry->start < end) { 849 850 /* 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->type == OBJT_SWAP || 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 return (error == KERN_SUCCESS ? 0 : ENOMEM); 1109 } 1110 1111 #ifndef _SYS_SYSPROTO_H_ 1112 struct mlockall_args { 1113 int how; 1114 }; 1115 #endif 1116 1117 int 1118 sys_mlockall(struct thread *td, struct mlockall_args *uap) 1119 { 1120 vm_map_t map; 1121 int error; 1122 1123 map = &td->td_proc->p_vmspace->vm_map; 1124 error = priv_check(td, PRIV_VM_MLOCK); 1125 if (error) 1126 return (error); 1127 1128 if ((uap->how == 0) || ((uap->how & ~(MCL_CURRENT|MCL_FUTURE)) != 0)) 1129 return (EINVAL); 1130 1131 /* 1132 * If wiring all pages in the process would cause it to exceed 1133 * a hard resource limit, return ENOMEM. 1134 */ 1135 if (!old_mlock && uap->how & MCL_CURRENT) { 1136 if (map->size > lim_cur(td, RLIMIT_MEMLOCK)) 1137 return (ENOMEM); 1138 } 1139 #ifdef RACCT 1140 if (racct_enable) { 1141 PROC_LOCK(td->td_proc); 1142 error = racct_set(td->td_proc, RACCT_MEMLOCK, map->size); 1143 PROC_UNLOCK(td->td_proc); 1144 if (error != 0) 1145 return (ENOMEM); 1146 } 1147 #endif 1148 1149 if (uap->how & MCL_FUTURE) { 1150 vm_map_lock(map); 1151 vm_map_modflags(map, MAP_WIREFUTURE, 0); 1152 vm_map_unlock(map); 1153 error = 0; 1154 } 1155 1156 if (uap->how & MCL_CURRENT) { 1157 /* 1158 * P1003.1-2001 mandates that all currently mapped pages 1159 * will be memory resident and locked (wired) upon return 1160 * from mlockall(). vm_map_wire() will wire pages, by 1161 * calling vm_fault_wire() for each page in the region. 1162 */ 1163 error = vm_map_wire(map, vm_map_min(map), vm_map_max(map), 1164 VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); 1165 if (error == KERN_SUCCESS) 1166 error = 0; 1167 else if (error == KERN_RESOURCE_SHORTAGE) 1168 error = ENOMEM; 1169 else 1170 error = EAGAIN; 1171 } 1172 #ifdef RACCT 1173 if (racct_enable && error != KERN_SUCCESS) { 1174 PROC_LOCK(td->td_proc); 1175 racct_set(td->td_proc, RACCT_MEMLOCK, 1176 ptoa(pmap_wired_count(map->pmap))); 1177 PROC_UNLOCK(td->td_proc); 1178 } 1179 #endif 1180 1181 return (error); 1182 } 1183 1184 #ifndef _SYS_SYSPROTO_H_ 1185 struct munlockall_args { 1186 register_t dummy; 1187 }; 1188 #endif 1189 1190 int 1191 sys_munlockall(struct thread *td, struct munlockall_args *uap) 1192 { 1193 vm_map_t map; 1194 int error; 1195 1196 map = &td->td_proc->p_vmspace->vm_map; 1197 error = priv_check(td, PRIV_VM_MUNLOCK); 1198 if (error) 1199 return (error); 1200 1201 /* Clear the MAP_WIREFUTURE flag from this vm_map. */ 1202 vm_map_lock(map); 1203 vm_map_modflags(map, 0, MAP_WIREFUTURE); 1204 vm_map_unlock(map); 1205 1206 /* Forcibly unwire all pages. */ 1207 error = vm_map_unwire(map, vm_map_min(map), vm_map_max(map), 1208 VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); 1209 #ifdef RACCT 1210 if (racct_enable && error == KERN_SUCCESS) { 1211 PROC_LOCK(td->td_proc); 1212 racct_set(td->td_proc, RACCT_MEMLOCK, 0); 1213 PROC_UNLOCK(td->td_proc); 1214 } 1215 #endif 1216 1217 return (error); 1218 } 1219 1220 #ifndef _SYS_SYSPROTO_H_ 1221 struct munlock_args { 1222 const void *addr; 1223 size_t len; 1224 }; 1225 #endif 1226 int 1227 sys_munlock(struct thread *td, struct munlock_args *uap) 1228 { 1229 1230 return (kern_munlock(td, (uintptr_t)uap->addr, uap->len)); 1231 } 1232 1233 int 1234 kern_munlock(struct thread *td, uintptr_t addr0, size_t size) 1235 { 1236 vm_offset_t addr, end, last, start; 1237 #ifdef RACCT 1238 vm_map_t map; 1239 #endif 1240 int error; 1241 1242 error = priv_check(td, PRIV_VM_MUNLOCK); 1243 if (error) 1244 return (error); 1245 addr = addr0; 1246 last = addr + size; 1247 start = trunc_page(addr); 1248 end = round_page(last); 1249 if (last < addr || end < addr) 1250 return (EINVAL); 1251 error = vm_map_unwire(&td->td_proc->p_vmspace->vm_map, start, end, 1252 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); 1253 #ifdef RACCT 1254 if (racct_enable && error == KERN_SUCCESS) { 1255 PROC_LOCK(td->td_proc); 1256 map = &td->td_proc->p_vmspace->vm_map; 1257 racct_set(td->td_proc, RACCT_MEMLOCK, 1258 ptoa(pmap_wired_count(map->pmap))); 1259 PROC_UNLOCK(td->td_proc); 1260 } 1261 #endif 1262 return (error == KERN_SUCCESS ? 0 : ENOMEM); 1263 } 1264 1265 /* 1266 * vm_mmap_vnode() 1267 * 1268 * Helper function for vm_mmap. Perform sanity check specific for mmap 1269 * operations on vnodes. 1270 */ 1271 int 1272 vm_mmap_vnode(struct thread *td, vm_size_t objsize, 1273 vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, 1274 struct vnode *vp, vm_ooffset_t *foffp, vm_object_t *objp, 1275 boolean_t *writecounted) 1276 { 1277 struct vattr va; 1278 vm_object_t obj; 1279 vm_ooffset_t foff; 1280 struct ucred *cred; 1281 int error, flags; 1282 bool writex; 1283 1284 cred = td->td_ucred; 1285 writex = (*maxprotp & VM_PROT_WRITE) != 0 && 1286 (*flagsp & MAP_SHARED) != 0; 1287 if ((error = vget(vp, LK_SHARED, td)) != 0) 1288 return (error); 1289 AUDIT_ARG_VNODE1(vp); 1290 foff = *foffp; 1291 flags = *flagsp; 1292 obj = vp->v_object; 1293 if (vp->v_type == VREG) { 1294 /* 1295 * Get the proper underlying object 1296 */ 1297 if (obj == NULL) { 1298 error = EINVAL; 1299 goto done; 1300 } 1301 if (obj->type == OBJT_VNODE && obj->handle != vp) { 1302 vput(vp); 1303 vp = (struct vnode *)obj->handle; 1304 /* 1305 * Bypass filesystems obey the mpsafety of the 1306 * underlying fs. Tmpfs never bypasses. 1307 */ 1308 error = vget(vp, LK_SHARED, td); 1309 if (error != 0) 1310 return (error); 1311 } 1312 if (writex) { 1313 *writecounted = TRUE; 1314 vm_pager_update_writecount(obj, 0, objsize); 1315 } 1316 } else { 1317 error = EINVAL; 1318 goto done; 1319 } 1320 if ((error = VOP_GETATTR(vp, &va, cred))) 1321 goto done; 1322 #ifdef MAC 1323 /* This relies on VM_PROT_* matching PROT_*. */ 1324 error = mac_vnode_check_mmap(cred, vp, (int)prot, flags); 1325 if (error != 0) 1326 goto done; 1327 #endif 1328 if ((flags & MAP_SHARED) != 0) { 1329 if ((va.va_flags & (SF_SNAPSHOT|IMMUTABLE|APPEND)) != 0) { 1330 if (prot & VM_PROT_WRITE) { 1331 error = EPERM; 1332 goto done; 1333 } 1334 *maxprotp &= ~VM_PROT_WRITE; 1335 } 1336 } 1337 /* 1338 * If it is a regular file without any references 1339 * we do not need to sync it. 1340 * Adjust object size to be the size of actual file. 1341 */ 1342 objsize = round_page(va.va_size); 1343 if (va.va_nlink == 0) 1344 flags |= MAP_NOSYNC; 1345 if (obj->type == OBJT_VNODE) { 1346 obj = vm_pager_allocate(OBJT_VNODE, vp, objsize, prot, foff, 1347 cred); 1348 if (obj == NULL) { 1349 error = ENOMEM; 1350 goto done; 1351 } 1352 } else { 1353 KASSERT(obj->type == OBJT_DEFAULT || obj->type == OBJT_SWAP, 1354 ("wrong object type")); 1355 vm_object_reference(obj); 1356 #if VM_NRESERVLEVEL > 0 1357 if ((obj->flags & OBJ_COLORED) == 0) { 1358 VM_OBJECT_WLOCK(obj); 1359 vm_object_color(obj, 0); 1360 VM_OBJECT_WUNLOCK(obj); 1361 } 1362 #endif 1363 } 1364 *objp = obj; 1365 *flagsp = flags; 1366 1367 VOP_MMAPPED(vp); 1368 1369 done: 1370 if (error != 0 && *writecounted) { 1371 *writecounted = FALSE; 1372 vm_pager_update_writecount(obj, objsize, 0); 1373 } 1374 vput(vp); 1375 return (error); 1376 } 1377 1378 /* 1379 * vm_mmap_cdev() 1380 * 1381 * Helper function for vm_mmap. Perform sanity check specific for mmap 1382 * operations on cdevs. 1383 */ 1384 int 1385 vm_mmap_cdev(struct thread *td, vm_size_t objsize, vm_prot_t prot, 1386 vm_prot_t *maxprotp, int *flagsp, struct cdev *cdev, struct cdevsw *dsw, 1387 vm_ooffset_t *foff, vm_object_t *objp) 1388 { 1389 vm_object_t obj; 1390 int error, flags; 1391 1392 flags = *flagsp; 1393 1394 if (dsw->d_flags & D_MMAP_ANON) { 1395 *objp = NULL; 1396 *foff = 0; 1397 *maxprotp = VM_PROT_ALL; 1398 *flagsp |= MAP_ANON; 1399 return (0); 1400 } 1401 /* 1402 * cdevs do not provide private mappings of any kind. 1403 */ 1404 if ((*maxprotp & VM_PROT_WRITE) == 0 && 1405 (prot & VM_PROT_WRITE) != 0) 1406 return (EACCES); 1407 if (flags & (MAP_PRIVATE|MAP_COPY)) 1408 return (EINVAL); 1409 /* 1410 * Force device mappings to be shared. 1411 */ 1412 flags |= MAP_SHARED; 1413 #ifdef MAC_XXX 1414 error = mac_cdev_check_mmap(td->td_ucred, cdev, (int)prot); 1415 if (error != 0) 1416 return (error); 1417 #endif 1418 /* 1419 * First, try d_mmap_single(). If that is not implemented 1420 * (returns ENODEV), fall back to using the device pager. 1421 * Note that d_mmap_single() must return a reference to the 1422 * object (it needs to bump the reference count of the object 1423 * it returns somehow). 1424 * 1425 * XXX assumes VM_PROT_* == PROT_* 1426 */ 1427 error = dsw->d_mmap_single(cdev, foff, objsize, objp, (int)prot); 1428 if (error != ENODEV) 1429 return (error); 1430 obj = vm_pager_allocate(OBJT_DEVICE, cdev, objsize, prot, *foff, 1431 td->td_ucred); 1432 if (obj == NULL) 1433 return (EINVAL); 1434 *objp = obj; 1435 *flagsp = flags; 1436 return (0); 1437 } 1438 1439 /* 1440 * vm_mmap() 1441 * 1442 * Internal version of mmap used by exec, sys5 shared memory, and 1443 * various device drivers. Handle is either a vnode pointer, a 1444 * character device, or NULL for MAP_ANON. 1445 */ 1446 int 1447 vm_mmap(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, 1448 vm_prot_t maxprot, int flags, 1449 objtype_t handle_type, void *handle, 1450 vm_ooffset_t foff) 1451 { 1452 vm_object_t object; 1453 struct thread *td = curthread; 1454 int error; 1455 boolean_t writecounted; 1456 1457 if (size == 0) 1458 return (EINVAL); 1459 1460 size = round_page(size); 1461 object = NULL; 1462 writecounted = FALSE; 1463 1464 /* 1465 * Lookup/allocate object. 1466 */ 1467 switch (handle_type) { 1468 case OBJT_DEVICE: { 1469 struct cdevsw *dsw; 1470 struct cdev *cdev; 1471 int ref; 1472 1473 cdev = handle; 1474 dsw = dev_refthread(cdev, &ref); 1475 if (dsw == NULL) 1476 return (ENXIO); 1477 error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, cdev, 1478 dsw, &foff, &object); 1479 dev_relthread(cdev, ref); 1480 break; 1481 } 1482 case OBJT_VNODE: 1483 error = vm_mmap_vnode(td, size, prot, &maxprot, &flags, 1484 handle, &foff, &object, &writecounted); 1485 break; 1486 case OBJT_DEFAULT: 1487 if (handle == NULL) { 1488 error = 0; 1489 break; 1490 } 1491 /* FALLTHROUGH */ 1492 default: 1493 error = EINVAL; 1494 break; 1495 } 1496 if (error) 1497 return (error); 1498 1499 error = vm_mmap_object(map, addr, size, prot, maxprot, flags, object, 1500 foff, writecounted, td); 1501 if (error != 0 && object != NULL) { 1502 /* 1503 * If this mapping was accounted for in the vnode's 1504 * writecount, then undo that now. 1505 */ 1506 if (writecounted) 1507 vm_pager_release_writecount(object, 0, size); 1508 vm_object_deallocate(object); 1509 } 1510 return (error); 1511 } 1512 1513 /* 1514 * Internal version of mmap that maps a specific VM object into an 1515 * map. Called by mmap for MAP_ANON, vm_mmap, shm_mmap, and vn_mmap. 1516 */ 1517 int 1518 vm_mmap_object(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, 1519 vm_prot_t maxprot, int flags, vm_object_t object, vm_ooffset_t foff, 1520 boolean_t writecounted, struct thread *td) 1521 { 1522 boolean_t curmap, fitit; 1523 vm_offset_t max_addr; 1524 int docow, error, findspace, rv; 1525 1526 curmap = map == &td->td_proc->p_vmspace->vm_map; 1527 if (curmap) { 1528 RACCT_PROC_LOCK(td->td_proc); 1529 if (map->size + size > lim_cur(td, RLIMIT_VMEM)) { 1530 RACCT_PROC_UNLOCK(td->td_proc); 1531 return (ENOMEM); 1532 } 1533 if (racct_set(td->td_proc, RACCT_VMEM, map->size + size)) { 1534 RACCT_PROC_UNLOCK(td->td_proc); 1535 return (ENOMEM); 1536 } 1537 if (!old_mlock && map->flags & MAP_WIREFUTURE) { 1538 if (ptoa(pmap_wired_count(map->pmap)) + size > 1539 lim_cur(td, RLIMIT_MEMLOCK)) { 1540 racct_set_force(td->td_proc, RACCT_VMEM, 1541 map->size); 1542 RACCT_PROC_UNLOCK(td->td_proc); 1543 return (ENOMEM); 1544 } 1545 error = racct_set(td->td_proc, RACCT_MEMLOCK, 1546 ptoa(pmap_wired_count(map->pmap)) + size); 1547 if (error != 0) { 1548 racct_set_force(td->td_proc, RACCT_VMEM, 1549 map->size); 1550 RACCT_PROC_UNLOCK(td->td_proc); 1551 return (error); 1552 } 1553 } 1554 RACCT_PROC_UNLOCK(td->td_proc); 1555 } 1556 1557 /* 1558 * We currently can only deal with page aligned file offsets. 1559 * The mmap() system call already enforces this by subtracting 1560 * the page offset from the file offset, but checking here 1561 * catches errors in device drivers (e.g. d_single_mmap() 1562 * callbacks) and other internal mapping requests (such as in 1563 * exec). 1564 */ 1565 if (foff & PAGE_MASK) 1566 return (EINVAL); 1567 1568 if ((flags & MAP_FIXED) == 0) { 1569 fitit = TRUE; 1570 *addr = round_page(*addr); 1571 } else { 1572 if (*addr != trunc_page(*addr)) 1573 return (EINVAL); 1574 fitit = FALSE; 1575 } 1576 1577 if (flags & MAP_ANON) { 1578 if (object != NULL || foff != 0) 1579 return (EINVAL); 1580 docow = 0; 1581 } else if (flags & MAP_PREFAULT_READ) 1582 docow = MAP_PREFAULT; 1583 else 1584 docow = MAP_PREFAULT_PARTIAL; 1585 1586 if ((flags & (MAP_ANON|MAP_SHARED)) == 0) 1587 docow |= MAP_COPY_ON_WRITE; 1588 if (flags & MAP_NOSYNC) 1589 docow |= MAP_DISABLE_SYNCER; 1590 if (flags & MAP_NOCORE) 1591 docow |= MAP_DISABLE_COREDUMP; 1592 /* Shared memory is also shared with children. */ 1593 if (flags & MAP_SHARED) 1594 docow |= MAP_INHERIT_SHARE; 1595 if (writecounted) 1596 docow |= MAP_WRITECOUNT; 1597 if (flags & MAP_STACK) { 1598 if (object != NULL) 1599 return (EINVAL); 1600 docow |= MAP_STACK_GROWS_DOWN; 1601 } 1602 if ((flags & MAP_EXCL) != 0) 1603 docow |= MAP_CHECK_EXCL; 1604 if ((flags & MAP_GUARD) != 0) 1605 docow |= MAP_CREATE_GUARD; 1606 1607 if (fitit) { 1608 if ((flags & MAP_ALIGNMENT_MASK) == MAP_ALIGNED_SUPER) 1609 findspace = VMFS_SUPER_SPACE; 1610 else if ((flags & MAP_ALIGNMENT_MASK) != 0) 1611 findspace = VMFS_ALIGNED_SPACE(flags >> 1612 MAP_ALIGNMENT_SHIFT); 1613 else 1614 findspace = VMFS_OPTIMAL_SPACE; 1615 max_addr = 0; 1616 #ifdef MAP_32BIT 1617 if ((flags & MAP_32BIT) != 0) 1618 max_addr = MAP_32BIT_MAX_ADDR; 1619 #endif 1620 if (curmap) { 1621 rv = vm_map_find_min(map, object, foff, addr, size, 1622 round_page((vm_offset_t)td->td_proc->p_vmspace-> 1623 vm_daddr + lim_max(td, RLIMIT_DATA)), max_addr, 1624 findspace, prot, maxprot, docow); 1625 } else { 1626 rv = vm_map_find(map, object, foff, addr, size, 1627 max_addr, findspace, prot, maxprot, docow); 1628 } 1629 } else { 1630 rv = vm_map_fixed(map, object, foff, *addr, size, 1631 prot, maxprot, docow); 1632 } 1633 1634 if (rv == KERN_SUCCESS) { 1635 /* 1636 * If the process has requested that all future mappings 1637 * be wired, then heed this. 1638 */ 1639 if ((map->flags & MAP_WIREFUTURE) != 0) { 1640 vm_map_lock(map); 1641 if ((map->flags & MAP_WIREFUTURE) != 0) 1642 (void)vm_map_wire_locked(map, *addr, 1643 *addr + size, VM_MAP_WIRE_USER | 1644 ((flags & MAP_STACK) ? VM_MAP_WIRE_HOLESOK : 1645 VM_MAP_WIRE_NOHOLES)); 1646 vm_map_unlock(map); 1647 } 1648 } 1649 return (vm_mmap_to_errno(rv)); 1650 } 1651 1652 /* 1653 * Translate a Mach VM return code to zero on success or the appropriate errno 1654 * on failure. 1655 */ 1656 int 1657 vm_mmap_to_errno(int rv) 1658 { 1659 1660 switch (rv) { 1661 case KERN_SUCCESS: 1662 return (0); 1663 case KERN_INVALID_ADDRESS: 1664 case KERN_NO_SPACE: 1665 return (ENOMEM); 1666 case KERN_PROTECTION_FAILURE: 1667 return (EACCES); 1668 default: 1669 return (EINVAL); 1670 } 1671 } 1672