1 /*- 2 * Copyright (c) 1988 University of Utah. 3 * Copyright (c) 1991, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * the Systems Programming Group of the University of Utah Computer 8 * Science Department. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * from: Utah $Hdr: vm_mmap.c 1.6 91/10/21$ 35 * 36 * @(#)vm_mmap.c 8.4 (Berkeley) 1/12/94 37 */ 38 39 /* 40 * Mapped file (mmap) interface to VM 41 */ 42 43 #include <sys/cdefs.h> 44 __FBSDID("$FreeBSD$"); 45 46 #include "opt_compat.h" 47 #include "opt_hwpmc_hooks.h" 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/capsicum.h> 52 #include <sys/kernel.h> 53 #include <sys/lock.h> 54 #include <sys/mutex.h> 55 #include <sys/sysproto.h> 56 #include <sys/filedesc.h> 57 #include <sys/priv.h> 58 #include <sys/proc.h> 59 #include <sys/procctl.h> 60 #include <sys/racct.h> 61 #include <sys/resource.h> 62 #include <sys/resourcevar.h> 63 #include <sys/rwlock.h> 64 #include <sys/sysctl.h> 65 #include <sys/vnode.h> 66 #include <sys/fcntl.h> 67 #include <sys/file.h> 68 #include <sys/mman.h> 69 #include <sys/mount.h> 70 #include <sys/conf.h> 71 #include <sys/stat.h> 72 #include <sys/syscallsubr.h> 73 #include <sys/sysent.h> 74 #include <sys/vmmeter.h> 75 76 #include <security/mac/mac_framework.h> 77 78 #include <vm/vm.h> 79 #include <vm/vm_param.h> 80 #include <vm/pmap.h> 81 #include <vm/vm_map.h> 82 #include <vm/vm_object.h> 83 #include <vm/vm_page.h> 84 #include <vm/vm_pager.h> 85 #include <vm/vm_pageout.h> 86 #include <vm/vm_extern.h> 87 #include <vm/vm_page.h> 88 #include <vm/vnode_pager.h> 89 90 #ifdef HWPMC_HOOKS 91 #include <sys/pmckern.h> 92 #endif 93 94 int old_mlock = 0; 95 SYSCTL_INT(_vm, OID_AUTO, old_mlock, CTLFLAG_RWTUN, &old_mlock, 0, 96 "Do not apply RLIMIT_MEMLOCK on mlockall"); 97 98 #ifdef MAP_32BIT 99 #define MAP_32BIT_MAX_ADDR ((vm_offset_t)1 << 31) 100 #endif 101 102 static int vm_mmap_vnode(struct thread *, vm_size_t, vm_prot_t, vm_prot_t *, 103 int *, struct vnode *, vm_ooffset_t *, vm_object_t *, boolean_t *); 104 static int vm_mmap_cdev(struct thread *, vm_size_t, vm_prot_t, vm_prot_t *, 105 int *, struct cdev *, vm_ooffset_t *, vm_object_t *); 106 static int vm_mmap_shm(struct thread *, vm_size_t, vm_prot_t, vm_prot_t *, 107 int *, struct shmfd *, vm_ooffset_t, vm_object_t *); 108 109 #ifndef _SYS_SYSPROTO_H_ 110 struct sbrk_args { 111 int incr; 112 }; 113 #endif 114 115 /* 116 * MPSAFE 117 */ 118 /* ARGSUSED */ 119 int 120 sys_sbrk(td, uap) 121 struct thread *td; 122 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 /* 135 * MPSAFE 136 */ 137 /* ARGSUSED */ 138 int 139 sys_sstk(td, uap) 140 struct thread *td; 141 struct sstk_args *uap; 142 { 143 /* Not yet implemented */ 144 return (EOPNOTSUPP); 145 } 146 147 #if defined(COMPAT_43) 148 #ifndef _SYS_SYSPROTO_H_ 149 struct getpagesize_args { 150 int dummy; 151 }; 152 #endif 153 154 int 155 ogetpagesize(td, uap) 156 struct thread *td; 157 struct getpagesize_args *uap; 158 { 159 /* MP SAFE */ 160 td->td_retval[0] = PAGE_SIZE; 161 return (0); 162 } 163 #endif /* COMPAT_43 */ 164 165 166 /* 167 * Memory Map (mmap) system call. Note that the file offset 168 * and address are allowed to be NOT page aligned, though if 169 * the MAP_FIXED flag it set, both must have the same remainder 170 * modulo the PAGE_SIZE (POSIX 1003.1b). If the address is not 171 * page-aligned, the actual mapping starts at trunc_page(addr) 172 * and the return value is adjusted up by the page offset. 173 * 174 * Generally speaking, only character devices which are themselves 175 * memory-based, such as a video framebuffer, can be mmap'd. Otherwise 176 * there would be no cache coherency between a descriptor and a VM mapping 177 * both to the same character device. 178 */ 179 #ifndef _SYS_SYSPROTO_H_ 180 struct mmap_args { 181 void *addr; 182 size_t len; 183 int prot; 184 int flags; 185 int fd; 186 long pad; 187 off_t pos; 188 }; 189 #endif 190 191 /* 192 * MPSAFE 193 */ 194 int 195 sys_mmap(td, uap) 196 struct thread *td; 197 struct mmap_args *uap; 198 { 199 #ifdef HWPMC_HOOKS 200 struct pmckern_map_in pkm; 201 #endif 202 struct file *fp; 203 struct vnode *vp; 204 vm_offset_t addr; 205 vm_size_t size, pageoff; 206 vm_prot_t cap_maxprot, maxprot; 207 void *handle; 208 objtype_t handle_type; 209 int align, error, flags, prot; 210 off_t pos; 211 struct vmspace *vms = td->td_proc->p_vmspace; 212 cap_rights_t rights; 213 214 addr = (vm_offset_t) uap->addr; 215 size = uap->len; 216 prot = uap->prot; 217 flags = uap->flags; 218 pos = uap->pos; 219 220 fp = NULL; 221 222 /* 223 * Enforce the constraints. 224 * Mapping of length 0 is only allowed for old binaries. 225 * Anonymous mapping shall specify -1 as filedescriptor and 226 * zero position for new code. Be nice to ancient a.out 227 * binaries and correct pos for anonymous mapping, since old 228 * ld.so sometimes issues anonymous map requests with non-zero 229 * pos. 230 */ 231 if (!SV_CURPROC_FLAG(SV_AOUT)) { 232 if ((uap->len == 0 && curproc->p_osrel >= P_OSREL_MAP_ANON) || 233 ((flags & MAP_ANON) != 0 && (uap->fd != -1 || pos != 0))) 234 return (EINVAL); 235 } else { 236 if ((flags & MAP_ANON) != 0) 237 pos = 0; 238 } 239 240 if (flags & MAP_STACK) { 241 if ((uap->fd != -1) || 242 ((prot & (PROT_READ | PROT_WRITE)) != (PROT_READ | PROT_WRITE))) 243 return (EINVAL); 244 flags |= MAP_ANON; 245 pos = 0; 246 } 247 if ((flags & ~(MAP_SHARED | MAP_PRIVATE | MAP_FIXED | MAP_RENAME | 248 MAP_NORESERVE | MAP_HASSEMAPHORE | MAP_STACK | MAP_NOSYNC | 249 MAP_ANON | MAP_EXCL | MAP_NOCORE | MAP_PREFAULT_READ | 250 #ifdef MAP_32BIT 251 MAP_32BIT | 252 #endif 253 MAP_ALIGNMENT_MASK)) != 0) 254 return (EINVAL); 255 if ((flags & (MAP_EXCL | MAP_FIXED)) == MAP_EXCL) 256 return (EINVAL); 257 if ((flags & (MAP_SHARED | MAP_PRIVATE)) == (MAP_SHARED | MAP_PRIVATE)) 258 return (EINVAL); 259 if (prot != PROT_NONE && 260 (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC)) != 0) 261 return (EINVAL); 262 263 /* 264 * Align the file position to a page boundary, 265 * and save its page offset component. 266 */ 267 pageoff = (pos & PAGE_MASK); 268 pos -= pageoff; 269 270 /* Adjust size for rounding (on both ends). */ 271 size += pageoff; /* low end... */ 272 size = (vm_size_t) round_page(size); /* hi end */ 273 274 /* Ensure alignment is at least a page and fits in a pointer. */ 275 align = flags & MAP_ALIGNMENT_MASK; 276 if (align != 0 && align != MAP_ALIGNED_SUPER && 277 (align >> MAP_ALIGNMENT_SHIFT >= sizeof(void *) * NBBY || 278 align >> MAP_ALIGNMENT_SHIFT < PAGE_SHIFT)) 279 return (EINVAL); 280 281 /* 282 * Check for illegal addresses. Watch out for address wrap... Note 283 * that VM_*_ADDRESS are not constants due to casts (argh). 284 */ 285 if (flags & MAP_FIXED) { 286 /* 287 * The specified address must have the same remainder 288 * as the file offset taken modulo PAGE_SIZE, so it 289 * should be aligned after adjustment by pageoff. 290 */ 291 addr -= pageoff; 292 if (addr & PAGE_MASK) 293 return (EINVAL); 294 295 /* Address range must be all in user VM space. */ 296 if (addr < vm_map_min(&vms->vm_map) || 297 addr + size > vm_map_max(&vms->vm_map)) 298 return (EINVAL); 299 if (addr + size < addr) 300 return (EINVAL); 301 #ifdef MAP_32BIT 302 if (flags & MAP_32BIT && addr + size > MAP_32BIT_MAX_ADDR) 303 return (EINVAL); 304 } else if (flags & MAP_32BIT) { 305 /* 306 * For MAP_32BIT, override the hint if it is too high and 307 * do not bother moving the mapping past the heap (since 308 * the heap is usually above 2GB). 309 */ 310 if (addr + size > MAP_32BIT_MAX_ADDR) 311 addr = 0; 312 #endif 313 } else { 314 /* 315 * XXX for non-fixed mappings where no hint is provided or 316 * the hint would fall in the potential heap space, 317 * place it after the end of the largest possible heap. 318 * 319 * There should really be a pmap call to determine a reasonable 320 * location. 321 */ 322 PROC_LOCK(td->td_proc); 323 if (addr == 0 || 324 (addr >= round_page((vm_offset_t)vms->vm_taddr) && 325 addr < round_page((vm_offset_t)vms->vm_daddr + 326 lim_max(td->td_proc, RLIMIT_DATA)))) 327 addr = round_page((vm_offset_t)vms->vm_daddr + 328 lim_max(td->td_proc, RLIMIT_DATA)); 329 PROC_UNLOCK(td->td_proc); 330 } 331 if (flags & MAP_ANON) { 332 /* 333 * Mapping blank space is trivial. 334 */ 335 handle = NULL; 336 handle_type = OBJT_DEFAULT; 337 maxprot = VM_PROT_ALL; 338 cap_maxprot = VM_PROT_ALL; 339 } else { 340 /* 341 * Mapping file, get fp for validation and don't let the 342 * descriptor disappear on us if we block. Check capability 343 * rights, but also return the maximum rights to be combined 344 * with maxprot later. 345 */ 346 cap_rights_init(&rights, CAP_MMAP); 347 if (prot & PROT_READ) 348 cap_rights_set(&rights, CAP_MMAP_R); 349 if ((flags & MAP_SHARED) != 0) { 350 if (prot & PROT_WRITE) 351 cap_rights_set(&rights, CAP_MMAP_W); 352 } 353 if (prot & PROT_EXEC) 354 cap_rights_set(&rights, CAP_MMAP_X); 355 error = fget_mmap(td, uap->fd, &rights, &cap_maxprot, &fp); 356 if (error != 0) 357 goto done; 358 if ((flags & (MAP_SHARED | MAP_PRIVATE)) == 0 && 359 td->td_proc->p_osrel >= P_OSREL_MAP_FSTRICT) { 360 error = EINVAL; 361 goto done; 362 } 363 if (fp->f_type == DTYPE_SHM) { 364 handle = fp->f_data; 365 handle_type = OBJT_SWAP; 366 maxprot = VM_PROT_NONE; 367 368 /* FREAD should always be set. */ 369 if (fp->f_flag & FREAD) 370 maxprot |= VM_PROT_EXECUTE | VM_PROT_READ; 371 if (fp->f_flag & FWRITE) 372 maxprot |= VM_PROT_WRITE; 373 goto map; 374 } 375 if (fp->f_type != DTYPE_VNODE) { 376 error = ENODEV; 377 goto done; 378 } 379 #if defined(COMPAT_FREEBSD7) || defined(COMPAT_FREEBSD6) || \ 380 defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4) 381 /* 382 * POSIX shared-memory objects are defined to have 383 * kernel persistence, and are not defined to support 384 * read(2)/write(2) -- or even open(2). Thus, we can 385 * use MAP_ASYNC to trade on-disk coherence for speed. 386 * The shm_open(3) library routine turns on the FPOSIXSHM 387 * flag to request this behavior. 388 */ 389 if (fp->f_flag & FPOSIXSHM) 390 flags |= MAP_NOSYNC; 391 #endif 392 vp = fp->f_vnode; 393 /* 394 * Ensure that file and memory protections are 395 * compatible. Note that we only worry about 396 * writability if mapping is shared; in this case, 397 * current and max prot are dictated by the open file. 398 * XXX use the vnode instead? Problem is: what 399 * credentials do we use for determination? What if 400 * proc does a setuid? 401 */ 402 if (vp->v_mount != NULL && vp->v_mount->mnt_flag & MNT_NOEXEC) 403 maxprot = VM_PROT_NONE; 404 else 405 maxprot = VM_PROT_EXECUTE; 406 if (fp->f_flag & FREAD) { 407 maxprot |= VM_PROT_READ; 408 } else if (prot & PROT_READ) { 409 error = EACCES; 410 goto done; 411 } 412 /* 413 * If we are sharing potential changes (either via 414 * MAP_SHARED or via the implicit sharing of character 415 * device mappings), and we are trying to get write 416 * permission although we opened it without asking 417 * for it, bail out. 418 */ 419 if ((flags & MAP_SHARED) != 0) { 420 if ((fp->f_flag & FWRITE) != 0) { 421 maxprot |= VM_PROT_WRITE; 422 } else if ((prot & PROT_WRITE) != 0) { 423 error = EACCES; 424 goto done; 425 } 426 } else if (vp->v_type != VCHR || (fp->f_flag & FWRITE) != 0) { 427 maxprot |= VM_PROT_WRITE; 428 cap_maxprot |= VM_PROT_WRITE; 429 } 430 handle = (void *)vp; 431 handle_type = OBJT_VNODE; 432 } 433 map: 434 td->td_fpop = fp; 435 maxprot &= cap_maxprot; 436 437 /* This relies on VM_PROT_* matching PROT_*. */ 438 error = vm_mmap(&vms->vm_map, &addr, size, prot, maxprot, 439 flags, handle_type, handle, pos); 440 td->td_fpop = NULL; 441 #ifdef HWPMC_HOOKS 442 /* inform hwpmc(4) if an executable is being mapped */ 443 if (error == 0 && handle_type == OBJT_VNODE && 444 (prot & PROT_EXEC)) { 445 pkm.pm_file = handle; 446 pkm.pm_address = (uintptr_t) addr; 447 PMC_CALL_HOOK(td, PMC_FN_MMAP, (void *) &pkm); 448 } 449 #endif 450 if (error == 0) 451 td->td_retval[0] = (register_t) (addr + pageoff); 452 done: 453 if (fp) 454 fdrop(fp, td); 455 456 return (error); 457 } 458 459 int 460 freebsd6_mmap(struct thread *td, struct freebsd6_mmap_args *uap) 461 { 462 struct mmap_args oargs; 463 464 oargs.addr = uap->addr; 465 oargs.len = uap->len; 466 oargs.prot = uap->prot; 467 oargs.flags = uap->flags; 468 oargs.fd = uap->fd; 469 oargs.pos = uap->pos; 470 return (sys_mmap(td, &oargs)); 471 } 472 473 #ifdef COMPAT_43 474 #ifndef _SYS_SYSPROTO_H_ 475 struct ommap_args { 476 caddr_t addr; 477 int len; 478 int prot; 479 int flags; 480 int fd; 481 long pos; 482 }; 483 #endif 484 int 485 ommap(td, uap) 486 struct thread *td; 487 struct ommap_args *uap; 488 { 489 struct mmap_args nargs; 490 static const char cvtbsdprot[8] = { 491 0, 492 PROT_EXEC, 493 PROT_WRITE, 494 PROT_EXEC | PROT_WRITE, 495 PROT_READ, 496 PROT_EXEC | PROT_READ, 497 PROT_WRITE | PROT_READ, 498 PROT_EXEC | PROT_WRITE | PROT_READ, 499 }; 500 501 #define OMAP_ANON 0x0002 502 #define OMAP_COPY 0x0020 503 #define OMAP_SHARED 0x0010 504 #define OMAP_FIXED 0x0100 505 506 nargs.addr = uap->addr; 507 nargs.len = uap->len; 508 nargs.prot = cvtbsdprot[uap->prot & 0x7]; 509 #ifdef COMPAT_FREEBSD32 510 #if defined(__amd64__) 511 if (i386_read_exec && SV_PROC_FLAG(td->td_proc, SV_ILP32) && 512 nargs.prot != 0) 513 nargs.prot |= PROT_EXEC; 514 #endif 515 #endif 516 nargs.flags = 0; 517 if (uap->flags & OMAP_ANON) 518 nargs.flags |= MAP_ANON; 519 if (uap->flags & OMAP_COPY) 520 nargs.flags |= MAP_COPY; 521 if (uap->flags & OMAP_SHARED) 522 nargs.flags |= MAP_SHARED; 523 else 524 nargs.flags |= MAP_PRIVATE; 525 if (uap->flags & OMAP_FIXED) 526 nargs.flags |= MAP_FIXED; 527 nargs.fd = uap->fd; 528 nargs.pos = uap->pos; 529 return (sys_mmap(td, &nargs)); 530 } 531 #endif /* COMPAT_43 */ 532 533 534 #ifndef _SYS_SYSPROTO_H_ 535 struct msync_args { 536 void *addr; 537 size_t len; 538 int flags; 539 }; 540 #endif 541 /* 542 * MPSAFE 543 */ 544 int 545 sys_msync(td, uap) 546 struct thread *td; 547 struct msync_args *uap; 548 { 549 vm_offset_t addr; 550 vm_size_t size, pageoff; 551 int flags; 552 vm_map_t map; 553 int rv; 554 555 addr = (vm_offset_t) uap->addr; 556 size = uap->len; 557 flags = uap->flags; 558 559 pageoff = (addr & PAGE_MASK); 560 addr -= pageoff; 561 size += pageoff; 562 size = (vm_size_t) round_page(size); 563 if (addr + size < addr) 564 return (EINVAL); 565 566 if ((flags & (MS_ASYNC|MS_INVALIDATE)) == (MS_ASYNC|MS_INVALIDATE)) 567 return (EINVAL); 568 569 map = &td->td_proc->p_vmspace->vm_map; 570 571 /* 572 * Clean the pages and interpret the return value. 573 */ 574 rv = vm_map_sync(map, addr, addr + size, (flags & MS_ASYNC) == 0, 575 (flags & MS_INVALIDATE) != 0); 576 switch (rv) { 577 case KERN_SUCCESS: 578 return (0); 579 case KERN_INVALID_ADDRESS: 580 return (ENOMEM); 581 case KERN_INVALID_ARGUMENT: 582 return (EBUSY); 583 case KERN_FAILURE: 584 return (EIO); 585 default: 586 return (EINVAL); 587 } 588 } 589 590 #ifndef _SYS_SYSPROTO_H_ 591 struct munmap_args { 592 void *addr; 593 size_t len; 594 }; 595 #endif 596 /* 597 * MPSAFE 598 */ 599 int 600 sys_munmap(td, uap) 601 struct thread *td; 602 struct munmap_args *uap; 603 { 604 #ifdef HWPMC_HOOKS 605 struct pmckern_map_out pkm; 606 vm_map_entry_t entry; 607 #endif 608 vm_offset_t addr; 609 vm_size_t size, pageoff; 610 vm_map_t map; 611 612 addr = (vm_offset_t) uap->addr; 613 size = uap->len; 614 if (size == 0) 615 return (EINVAL); 616 617 pageoff = (addr & PAGE_MASK); 618 addr -= pageoff; 619 size += pageoff; 620 size = (vm_size_t) round_page(size); 621 if (addr + size < addr) 622 return (EINVAL); 623 624 /* 625 * Check for illegal addresses. Watch out for address wrap... 626 */ 627 map = &td->td_proc->p_vmspace->vm_map; 628 if (addr < vm_map_min(map) || addr + size > vm_map_max(map)) 629 return (EINVAL); 630 vm_map_lock(map); 631 #ifdef HWPMC_HOOKS 632 /* 633 * Inform hwpmc if the address range being unmapped contains 634 * an executable region. 635 */ 636 pkm.pm_address = (uintptr_t) NULL; 637 if (vm_map_lookup_entry(map, addr, &entry)) { 638 for (; 639 entry != &map->header && entry->start < addr + size; 640 entry = entry->next) { 641 if (vm_map_check_protection(map, entry->start, 642 entry->end, VM_PROT_EXECUTE) == TRUE) { 643 pkm.pm_address = (uintptr_t) addr; 644 pkm.pm_size = (size_t) size; 645 break; 646 } 647 } 648 } 649 #endif 650 vm_map_delete(map, addr, addr + size); 651 652 #ifdef HWPMC_HOOKS 653 /* downgrade the lock to prevent a LOR with the pmc-sx lock */ 654 vm_map_lock_downgrade(map); 655 if (pkm.pm_address != (uintptr_t) NULL) 656 PMC_CALL_HOOK(td, PMC_FN_MUNMAP, (void *) &pkm); 657 vm_map_unlock_read(map); 658 #else 659 vm_map_unlock(map); 660 #endif 661 /* vm_map_delete returns nothing but KERN_SUCCESS anyway */ 662 return (0); 663 } 664 665 #ifndef _SYS_SYSPROTO_H_ 666 struct mprotect_args { 667 const void *addr; 668 size_t len; 669 int prot; 670 }; 671 #endif 672 /* 673 * MPSAFE 674 */ 675 int 676 sys_mprotect(td, uap) 677 struct thread *td; 678 struct mprotect_args *uap; 679 { 680 vm_offset_t addr; 681 vm_size_t size, pageoff; 682 vm_prot_t prot; 683 684 addr = (vm_offset_t) uap->addr; 685 size = uap->len; 686 prot = uap->prot & VM_PROT_ALL; 687 688 pageoff = (addr & PAGE_MASK); 689 addr -= pageoff; 690 size += pageoff; 691 size = (vm_size_t) round_page(size); 692 if (addr + size < addr) 693 return (EINVAL); 694 695 switch (vm_map_protect(&td->td_proc->p_vmspace->vm_map, addr, 696 addr + size, prot, FALSE)) { 697 case KERN_SUCCESS: 698 return (0); 699 case KERN_PROTECTION_FAILURE: 700 return (EACCES); 701 case KERN_RESOURCE_SHORTAGE: 702 return (ENOMEM); 703 } 704 return (EINVAL); 705 } 706 707 #ifndef _SYS_SYSPROTO_H_ 708 struct minherit_args { 709 void *addr; 710 size_t len; 711 int inherit; 712 }; 713 #endif 714 /* 715 * MPSAFE 716 */ 717 int 718 sys_minherit(td, uap) 719 struct thread *td; 720 struct minherit_args *uap; 721 { 722 vm_offset_t addr; 723 vm_size_t size, pageoff; 724 vm_inherit_t inherit; 725 726 addr = (vm_offset_t)uap->addr; 727 size = uap->len; 728 inherit = uap->inherit; 729 730 pageoff = (addr & PAGE_MASK); 731 addr -= pageoff; 732 size += pageoff; 733 size = (vm_size_t) round_page(size); 734 if (addr + size < addr) 735 return (EINVAL); 736 737 switch (vm_map_inherit(&td->td_proc->p_vmspace->vm_map, addr, 738 addr + size, inherit)) { 739 case KERN_SUCCESS: 740 return (0); 741 case KERN_PROTECTION_FAILURE: 742 return (EACCES); 743 } 744 return (EINVAL); 745 } 746 747 #ifndef _SYS_SYSPROTO_H_ 748 struct madvise_args { 749 void *addr; 750 size_t len; 751 int behav; 752 }; 753 #endif 754 755 /* 756 * MPSAFE 757 */ 758 int 759 sys_madvise(td, uap) 760 struct thread *td; 761 struct madvise_args *uap; 762 { 763 vm_offset_t start, end; 764 vm_map_t map; 765 int flags; 766 767 /* 768 * Check for our special case, advising the swap pager we are 769 * "immortal." 770 */ 771 if (uap->behav == MADV_PROTECT) { 772 flags = PPROT_SET; 773 return (kern_procctl(td, P_PID, td->td_proc->p_pid, 774 PROC_SPROTECT, &flags)); 775 } 776 777 /* 778 * Check for illegal behavior 779 */ 780 if (uap->behav < 0 || uap->behav > MADV_CORE) 781 return (EINVAL); 782 /* 783 * Check for illegal addresses. Watch out for address wrap... Note 784 * that VM_*_ADDRESS are not constants due to casts (argh). 785 */ 786 map = &td->td_proc->p_vmspace->vm_map; 787 if ((vm_offset_t)uap->addr < vm_map_min(map) || 788 (vm_offset_t)uap->addr + uap->len > vm_map_max(map)) 789 return (EINVAL); 790 if (((vm_offset_t) uap->addr + uap->len) < (vm_offset_t) uap->addr) 791 return (EINVAL); 792 793 /* 794 * Since this routine is only advisory, we default to conservative 795 * behavior. 796 */ 797 start = trunc_page((vm_offset_t) uap->addr); 798 end = round_page((vm_offset_t) uap->addr + uap->len); 799 800 if (vm_map_madvise(map, start, end, uap->behav)) 801 return (EINVAL); 802 return (0); 803 } 804 805 #ifndef _SYS_SYSPROTO_H_ 806 struct mincore_args { 807 const void *addr; 808 size_t len; 809 char *vec; 810 }; 811 #endif 812 813 /* 814 * MPSAFE 815 */ 816 int 817 sys_mincore(td, uap) 818 struct thread *td; 819 struct mincore_args *uap; 820 { 821 vm_offset_t addr, first_addr; 822 vm_offset_t end, cend; 823 pmap_t pmap; 824 vm_map_t map; 825 char *vec; 826 int error = 0; 827 int vecindex, lastvecindex; 828 vm_map_entry_t current; 829 vm_map_entry_t entry; 830 vm_object_t object; 831 vm_paddr_t locked_pa; 832 vm_page_t m; 833 vm_pindex_t pindex; 834 int mincoreinfo; 835 unsigned int timestamp; 836 boolean_t locked; 837 838 /* 839 * Make sure that the addresses presented are valid for user 840 * mode. 841 */ 842 first_addr = addr = trunc_page((vm_offset_t) uap->addr); 843 end = addr + (vm_size_t)round_page(uap->len); 844 map = &td->td_proc->p_vmspace->vm_map; 845 if (end > vm_map_max(map) || end < addr) 846 return (ENOMEM); 847 848 /* 849 * Address of byte vector 850 */ 851 vec = uap->vec; 852 853 pmap = vmspace_pmap(td->td_proc->p_vmspace); 854 855 vm_map_lock_read(map); 856 RestartScan: 857 timestamp = map->timestamp; 858 859 if (!vm_map_lookup_entry(map, addr, &entry)) { 860 vm_map_unlock_read(map); 861 return (ENOMEM); 862 } 863 864 /* 865 * Do this on a map entry basis so that if the pages are not 866 * in the current processes address space, we can easily look 867 * up the pages elsewhere. 868 */ 869 lastvecindex = -1; 870 for (current = entry; 871 (current != &map->header) && (current->start < end); 872 current = current->next) { 873 874 /* 875 * check for contiguity 876 */ 877 if (current->end < end && 878 (entry->next == &map->header || 879 current->next->start > current->end)) { 880 vm_map_unlock_read(map); 881 return (ENOMEM); 882 } 883 884 /* 885 * ignore submaps (for now) or null objects 886 */ 887 if ((current->eflags & MAP_ENTRY_IS_SUB_MAP) || 888 current->object.vm_object == NULL) 889 continue; 890 891 /* 892 * limit this scan to the current map entry and the 893 * limits for the mincore call 894 */ 895 if (addr < current->start) 896 addr = current->start; 897 cend = current->end; 898 if (cend > end) 899 cend = end; 900 901 /* 902 * scan this entry one page at a time 903 */ 904 while (addr < cend) { 905 /* 906 * Check pmap first, it is likely faster, also 907 * it can provide info as to whether we are the 908 * one referencing or modifying the page. 909 */ 910 object = NULL; 911 locked_pa = 0; 912 retry: 913 m = NULL; 914 mincoreinfo = pmap_mincore(pmap, addr, &locked_pa); 915 if (locked_pa != 0) { 916 /* 917 * The page is mapped by this process but not 918 * both accessed and modified. It is also 919 * managed. Acquire the object lock so that 920 * other mappings might be examined. 921 */ 922 m = PHYS_TO_VM_PAGE(locked_pa); 923 if (m->object != object) { 924 if (object != NULL) 925 VM_OBJECT_WUNLOCK(object); 926 object = m->object; 927 locked = VM_OBJECT_TRYWLOCK(object); 928 vm_page_unlock(m); 929 if (!locked) { 930 VM_OBJECT_WLOCK(object); 931 vm_page_lock(m); 932 goto retry; 933 } 934 } else 935 vm_page_unlock(m); 936 KASSERT(m->valid == VM_PAGE_BITS_ALL, 937 ("mincore: page %p is mapped but invalid", 938 m)); 939 } else if (mincoreinfo == 0) { 940 /* 941 * The page is not mapped by this process. If 942 * the object implements managed pages, then 943 * determine if the page is resident so that 944 * the mappings might be examined. 945 */ 946 if (current->object.vm_object != object) { 947 if (object != NULL) 948 VM_OBJECT_WUNLOCK(object); 949 object = current->object.vm_object; 950 VM_OBJECT_WLOCK(object); 951 } 952 if (object->type == OBJT_DEFAULT || 953 object->type == OBJT_SWAP || 954 object->type == OBJT_VNODE) { 955 pindex = OFF_TO_IDX(current->offset + 956 (addr - current->start)); 957 m = vm_page_lookup(object, pindex); 958 if (m == NULL && 959 vm_page_is_cached(object, pindex)) 960 mincoreinfo = MINCORE_INCORE; 961 if (m != NULL && m->valid == 0) 962 m = NULL; 963 if (m != NULL) 964 mincoreinfo = MINCORE_INCORE; 965 } 966 } 967 if (m != NULL) { 968 /* Examine other mappings to the page. */ 969 if (m->dirty == 0 && pmap_is_modified(m)) 970 vm_page_dirty(m); 971 if (m->dirty != 0) 972 mincoreinfo |= MINCORE_MODIFIED_OTHER; 973 /* 974 * The first test for PGA_REFERENCED is an 975 * optimization. The second test is 976 * required because a concurrent pmap 977 * operation could clear the last reference 978 * and set PGA_REFERENCED before the call to 979 * pmap_is_referenced(). 980 */ 981 if ((m->aflags & PGA_REFERENCED) != 0 || 982 pmap_is_referenced(m) || 983 (m->aflags & PGA_REFERENCED) != 0) 984 mincoreinfo |= MINCORE_REFERENCED_OTHER; 985 } 986 if (object != NULL) 987 VM_OBJECT_WUNLOCK(object); 988 989 /* 990 * subyte may page fault. In case it needs to modify 991 * the map, we release the lock. 992 */ 993 vm_map_unlock_read(map); 994 995 /* 996 * calculate index into user supplied byte vector 997 */ 998 vecindex = OFF_TO_IDX(addr - first_addr); 999 1000 /* 1001 * If we have skipped map entries, we need to make sure that 1002 * the byte vector is zeroed for those skipped entries. 1003 */ 1004 while ((lastvecindex + 1) < vecindex) { 1005 ++lastvecindex; 1006 error = subyte(vec + lastvecindex, 0); 1007 if (error) { 1008 error = EFAULT; 1009 goto done2; 1010 } 1011 } 1012 1013 /* 1014 * Pass the page information to the user 1015 */ 1016 error = subyte(vec + vecindex, mincoreinfo); 1017 if (error) { 1018 error = EFAULT; 1019 goto done2; 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 1030 lastvecindex = vecindex; 1031 addr += PAGE_SIZE; 1032 } 1033 } 1034 1035 /* 1036 * subyte may page fault. In case it needs to modify 1037 * the map, we release the lock. 1038 */ 1039 vm_map_unlock_read(map); 1040 1041 /* 1042 * Zero the last entries in the byte vector. 1043 */ 1044 vecindex = OFF_TO_IDX(end - first_addr); 1045 while ((lastvecindex + 1) < vecindex) { 1046 ++lastvecindex; 1047 error = subyte(vec + lastvecindex, 0); 1048 if (error) { 1049 error = EFAULT; 1050 goto done2; 1051 } 1052 } 1053 1054 /* 1055 * If the map has changed, due to the subyte, the previous 1056 * output may be invalid. 1057 */ 1058 vm_map_lock_read(map); 1059 if (timestamp != map->timestamp) 1060 goto RestartScan; 1061 vm_map_unlock_read(map); 1062 done2: 1063 return (error); 1064 } 1065 1066 #ifndef _SYS_SYSPROTO_H_ 1067 struct mlock_args { 1068 const void *addr; 1069 size_t len; 1070 }; 1071 #endif 1072 /* 1073 * MPSAFE 1074 */ 1075 int 1076 sys_mlock(td, uap) 1077 struct thread *td; 1078 struct mlock_args *uap; 1079 { 1080 1081 return (vm_mlock(td->td_proc, td->td_ucred, uap->addr, uap->len)); 1082 } 1083 1084 int 1085 vm_mlock(struct proc *proc, struct ucred *cred, const void *addr0, size_t len) 1086 { 1087 vm_offset_t addr, end, last, start; 1088 vm_size_t npages, size; 1089 vm_map_t map; 1090 unsigned long nsize; 1091 int error; 1092 1093 error = priv_check_cred(cred, PRIV_VM_MLOCK, 0); 1094 if (error) 1095 return (error); 1096 addr = (vm_offset_t)addr0; 1097 size = len; 1098 last = addr + size; 1099 start = trunc_page(addr); 1100 end = round_page(last); 1101 if (last < addr || end < addr) 1102 return (EINVAL); 1103 npages = atop(end - start); 1104 if (npages > vm_page_max_wired) 1105 return (ENOMEM); 1106 map = &proc->p_vmspace->vm_map; 1107 PROC_LOCK(proc); 1108 nsize = ptoa(npages + pmap_wired_count(map->pmap)); 1109 if (nsize > lim_cur(proc, RLIMIT_MEMLOCK)) { 1110 PROC_UNLOCK(proc); 1111 return (ENOMEM); 1112 } 1113 PROC_UNLOCK(proc); 1114 if (npages + vm_cnt.v_wire_count > vm_page_max_wired) 1115 return (EAGAIN); 1116 #ifdef RACCT 1117 PROC_LOCK(proc); 1118 error = racct_set(proc, RACCT_MEMLOCK, nsize); 1119 PROC_UNLOCK(proc); 1120 if (error != 0) 1121 return (ENOMEM); 1122 #endif 1123 error = vm_map_wire(map, start, end, 1124 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); 1125 #ifdef RACCT 1126 if (error != KERN_SUCCESS) { 1127 PROC_LOCK(proc); 1128 racct_set(proc, RACCT_MEMLOCK, 1129 ptoa(pmap_wired_count(map->pmap))); 1130 PROC_UNLOCK(proc); 1131 } 1132 #endif 1133 return (error == KERN_SUCCESS ? 0 : ENOMEM); 1134 } 1135 1136 #ifndef _SYS_SYSPROTO_H_ 1137 struct mlockall_args { 1138 int how; 1139 }; 1140 #endif 1141 1142 /* 1143 * MPSAFE 1144 */ 1145 int 1146 sys_mlockall(td, uap) 1147 struct thread *td; 1148 struct mlockall_args *uap; 1149 { 1150 vm_map_t map; 1151 int error; 1152 1153 map = &td->td_proc->p_vmspace->vm_map; 1154 error = priv_check(td, PRIV_VM_MLOCK); 1155 if (error) 1156 return (error); 1157 1158 if ((uap->how == 0) || ((uap->how & ~(MCL_CURRENT|MCL_FUTURE)) != 0)) 1159 return (EINVAL); 1160 1161 /* 1162 * If wiring all pages in the process would cause it to exceed 1163 * a hard resource limit, return ENOMEM. 1164 */ 1165 if (!old_mlock && uap->how & MCL_CURRENT) { 1166 PROC_LOCK(td->td_proc); 1167 if (map->size > lim_cur(td->td_proc, RLIMIT_MEMLOCK)) { 1168 PROC_UNLOCK(td->td_proc); 1169 return (ENOMEM); 1170 } 1171 PROC_UNLOCK(td->td_proc); 1172 } 1173 #ifdef RACCT 1174 PROC_LOCK(td->td_proc); 1175 error = racct_set(td->td_proc, RACCT_MEMLOCK, map->size); 1176 PROC_UNLOCK(td->td_proc); 1177 if (error != 0) 1178 return (ENOMEM); 1179 #endif 1180 1181 if (uap->how & MCL_FUTURE) { 1182 vm_map_lock(map); 1183 vm_map_modflags(map, MAP_WIREFUTURE, 0); 1184 vm_map_unlock(map); 1185 error = 0; 1186 } 1187 1188 if (uap->how & MCL_CURRENT) { 1189 /* 1190 * P1003.1-2001 mandates that all currently mapped pages 1191 * will be memory resident and locked (wired) upon return 1192 * from mlockall(). vm_map_wire() will wire pages, by 1193 * calling vm_fault_wire() for each page in the region. 1194 */ 1195 error = vm_map_wire(map, vm_map_min(map), vm_map_max(map), 1196 VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); 1197 error = (error == KERN_SUCCESS ? 0 : EAGAIN); 1198 } 1199 #ifdef RACCT 1200 if (error != KERN_SUCCESS) { 1201 PROC_LOCK(td->td_proc); 1202 racct_set(td->td_proc, RACCT_MEMLOCK, 1203 ptoa(pmap_wired_count(map->pmap))); 1204 PROC_UNLOCK(td->td_proc); 1205 } 1206 #endif 1207 1208 return (error); 1209 } 1210 1211 #ifndef _SYS_SYSPROTO_H_ 1212 struct munlockall_args { 1213 register_t dummy; 1214 }; 1215 #endif 1216 1217 /* 1218 * MPSAFE 1219 */ 1220 int 1221 sys_munlockall(td, uap) 1222 struct thread *td; 1223 struct munlockall_args *uap; 1224 { 1225 vm_map_t map; 1226 int error; 1227 1228 map = &td->td_proc->p_vmspace->vm_map; 1229 error = priv_check(td, PRIV_VM_MUNLOCK); 1230 if (error) 1231 return (error); 1232 1233 /* Clear the MAP_WIREFUTURE flag from this vm_map. */ 1234 vm_map_lock(map); 1235 vm_map_modflags(map, 0, MAP_WIREFUTURE); 1236 vm_map_unlock(map); 1237 1238 /* Forcibly unwire all pages. */ 1239 error = vm_map_unwire(map, vm_map_min(map), vm_map_max(map), 1240 VM_MAP_WIRE_USER|VM_MAP_WIRE_HOLESOK); 1241 #ifdef RACCT 1242 if (error == KERN_SUCCESS) { 1243 PROC_LOCK(td->td_proc); 1244 racct_set(td->td_proc, RACCT_MEMLOCK, 0); 1245 PROC_UNLOCK(td->td_proc); 1246 } 1247 #endif 1248 1249 return (error); 1250 } 1251 1252 #ifndef _SYS_SYSPROTO_H_ 1253 struct munlock_args { 1254 const void *addr; 1255 size_t len; 1256 }; 1257 #endif 1258 /* 1259 * MPSAFE 1260 */ 1261 int 1262 sys_munlock(td, uap) 1263 struct thread *td; 1264 struct munlock_args *uap; 1265 { 1266 vm_offset_t addr, end, last, start; 1267 vm_size_t size; 1268 #ifdef RACCT 1269 vm_map_t map; 1270 #endif 1271 int error; 1272 1273 error = priv_check(td, PRIV_VM_MUNLOCK); 1274 if (error) 1275 return (error); 1276 addr = (vm_offset_t)uap->addr; 1277 size = uap->len; 1278 last = addr + size; 1279 start = trunc_page(addr); 1280 end = round_page(last); 1281 if (last < addr || end < addr) 1282 return (EINVAL); 1283 error = vm_map_unwire(&td->td_proc->p_vmspace->vm_map, start, end, 1284 VM_MAP_WIRE_USER | VM_MAP_WIRE_NOHOLES); 1285 #ifdef RACCT 1286 if (error == KERN_SUCCESS) { 1287 PROC_LOCK(td->td_proc); 1288 map = &td->td_proc->p_vmspace->vm_map; 1289 racct_set(td->td_proc, RACCT_MEMLOCK, 1290 ptoa(pmap_wired_count(map->pmap))); 1291 PROC_UNLOCK(td->td_proc); 1292 } 1293 #endif 1294 return (error == KERN_SUCCESS ? 0 : ENOMEM); 1295 } 1296 1297 /* 1298 * vm_mmap_vnode() 1299 * 1300 * Helper function for vm_mmap. Perform sanity check specific for mmap 1301 * operations on vnodes. 1302 * 1303 * For VCHR vnodes, the vnode lock is held over the call to 1304 * vm_mmap_cdev() to keep vp->v_rdev valid. 1305 */ 1306 int 1307 vm_mmap_vnode(struct thread *td, vm_size_t objsize, 1308 vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, 1309 struct vnode *vp, vm_ooffset_t *foffp, vm_object_t *objp, 1310 boolean_t *writecounted) 1311 { 1312 struct vattr va; 1313 vm_object_t obj; 1314 vm_offset_t foff; 1315 struct mount *mp; 1316 struct ucred *cred; 1317 int error, flags, locktype; 1318 1319 mp = vp->v_mount; 1320 cred = td->td_ucred; 1321 if ((*maxprotp & VM_PROT_WRITE) && (*flagsp & MAP_SHARED)) 1322 locktype = LK_EXCLUSIVE; 1323 else 1324 locktype = LK_SHARED; 1325 if ((error = vget(vp, locktype, td)) != 0) 1326 return (error); 1327 foff = *foffp; 1328 flags = *flagsp; 1329 obj = vp->v_object; 1330 if (vp->v_type == VREG) { 1331 /* 1332 * Get the proper underlying object 1333 */ 1334 if (obj == NULL) { 1335 error = EINVAL; 1336 goto done; 1337 } 1338 if (obj->type == OBJT_VNODE && obj->handle != vp) { 1339 vput(vp); 1340 vp = (struct vnode *)obj->handle; 1341 /* 1342 * Bypass filesystems obey the mpsafety of the 1343 * underlying fs. Tmpfs never bypasses. 1344 */ 1345 error = vget(vp, locktype, td); 1346 if (error != 0) 1347 return (error); 1348 } 1349 if (locktype == LK_EXCLUSIVE) { 1350 *writecounted = TRUE; 1351 vnode_pager_update_writecount(obj, 0, objsize); 1352 } 1353 } else if (vp->v_type == VCHR) { 1354 error = vm_mmap_cdev(td, objsize, prot, maxprotp, flagsp, 1355 vp->v_rdev, foffp, objp); 1356 if (error == 0) 1357 goto mark_atime; 1358 goto done; 1359 } else { 1360 error = EINVAL; 1361 goto done; 1362 } 1363 if ((error = VOP_GETATTR(vp, &va, cred))) 1364 goto done; 1365 #ifdef MAC 1366 error = mac_vnode_check_mmap(cred, vp, prot, flags); 1367 if (error != 0) 1368 goto done; 1369 #endif 1370 if ((flags & MAP_SHARED) != 0) { 1371 if ((va.va_flags & (SF_SNAPSHOT|IMMUTABLE|APPEND)) != 0) { 1372 if (prot & PROT_WRITE) { 1373 error = EPERM; 1374 goto done; 1375 } 1376 *maxprotp &= ~VM_PROT_WRITE; 1377 } 1378 } 1379 /* 1380 * If it is a regular file without any references 1381 * we do not need to sync it. 1382 * Adjust object size to be the size of actual file. 1383 */ 1384 objsize = round_page(va.va_size); 1385 if (va.va_nlink == 0) 1386 flags |= MAP_NOSYNC; 1387 if (obj->type == OBJT_VNODE) 1388 obj = vm_pager_allocate(OBJT_VNODE, vp, objsize, prot, foff, 1389 cred); 1390 else { 1391 KASSERT(obj->type == OBJT_DEFAULT || obj->type == OBJT_SWAP, 1392 ("wrong object type")); 1393 vm_object_reference(obj); 1394 } 1395 if (obj == NULL) { 1396 error = ENOMEM; 1397 goto done; 1398 } 1399 *objp = obj; 1400 *flagsp = flags; 1401 1402 mark_atime: 1403 vfs_mark_atime(vp, cred); 1404 1405 done: 1406 if (error != 0 && *writecounted) { 1407 *writecounted = FALSE; 1408 vnode_pager_update_writecount(obj, objsize, 0); 1409 } 1410 vput(vp); 1411 return (error); 1412 } 1413 1414 /* 1415 * vm_mmap_cdev() 1416 * 1417 * MPSAFE 1418 * 1419 * Helper function for vm_mmap. Perform sanity check specific for mmap 1420 * operations on cdevs. 1421 */ 1422 int 1423 vm_mmap_cdev(struct thread *td, vm_size_t objsize, 1424 vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, 1425 struct cdev *cdev, vm_ooffset_t *foff, vm_object_t *objp) 1426 { 1427 vm_object_t obj; 1428 struct cdevsw *dsw; 1429 int error, flags, ref; 1430 1431 flags = *flagsp; 1432 1433 dsw = dev_refthread(cdev, &ref); 1434 if (dsw == NULL) 1435 return (ENXIO); 1436 if (dsw->d_flags & D_MMAP_ANON) { 1437 dev_relthread(cdev, ref); 1438 *maxprotp = VM_PROT_ALL; 1439 *flagsp |= MAP_ANON; 1440 return (0); 1441 } 1442 /* 1443 * cdevs do not provide private mappings of any kind. 1444 */ 1445 if ((*maxprotp & VM_PROT_WRITE) == 0 && 1446 (prot & PROT_WRITE) != 0) { 1447 dev_relthread(cdev, ref); 1448 return (EACCES); 1449 } 1450 if (flags & (MAP_PRIVATE|MAP_COPY)) { 1451 dev_relthread(cdev, ref); 1452 return (EINVAL); 1453 } 1454 /* 1455 * Force device mappings to be shared. 1456 */ 1457 flags |= MAP_SHARED; 1458 #ifdef MAC_XXX 1459 error = mac_cdev_check_mmap(td->td_ucred, cdev, prot); 1460 if (error != 0) { 1461 dev_relthread(cdev, ref); 1462 return (error); 1463 } 1464 #endif 1465 /* 1466 * First, try d_mmap_single(). If that is not implemented 1467 * (returns ENODEV), fall back to using the device pager. 1468 * Note that d_mmap_single() must return a reference to the 1469 * object (it needs to bump the reference count of the object 1470 * it returns somehow). 1471 * 1472 * XXX assumes VM_PROT_* == PROT_* 1473 */ 1474 error = dsw->d_mmap_single(cdev, foff, objsize, objp, (int)prot); 1475 dev_relthread(cdev, ref); 1476 if (error != ENODEV) 1477 return (error); 1478 obj = vm_pager_allocate(OBJT_DEVICE, cdev, objsize, prot, *foff, 1479 td->td_ucred); 1480 if (obj == NULL) 1481 return (EINVAL); 1482 *objp = obj; 1483 *flagsp = flags; 1484 return (0); 1485 } 1486 1487 /* 1488 * vm_mmap_shm() 1489 * 1490 * MPSAFE 1491 * 1492 * Helper function for vm_mmap. Perform sanity check specific for mmap 1493 * operations on shm file descriptors. 1494 */ 1495 int 1496 vm_mmap_shm(struct thread *td, vm_size_t objsize, 1497 vm_prot_t prot, vm_prot_t *maxprotp, int *flagsp, 1498 struct shmfd *shmfd, vm_ooffset_t foff, vm_object_t *objp) 1499 { 1500 int error; 1501 1502 if ((*flagsp & MAP_SHARED) != 0 && 1503 (*maxprotp & VM_PROT_WRITE) == 0 && 1504 (prot & PROT_WRITE) != 0) 1505 return (EACCES); 1506 #ifdef MAC 1507 error = mac_posixshm_check_mmap(td->td_ucred, shmfd, prot, *flagsp); 1508 if (error != 0) 1509 return (error); 1510 #endif 1511 error = shm_mmap(shmfd, objsize, foff, objp); 1512 if (error) 1513 return (error); 1514 return (0); 1515 } 1516 1517 /* 1518 * vm_mmap() 1519 * 1520 * MPSAFE 1521 * 1522 * Internal version of mmap. Currently used by mmap, exec, and sys5 1523 * shared memory. Handle is either a vnode pointer or NULL for MAP_ANON. 1524 */ 1525 int 1526 vm_mmap(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot, 1527 vm_prot_t maxprot, int flags, 1528 objtype_t handle_type, void *handle, 1529 vm_ooffset_t foff) 1530 { 1531 boolean_t fitit; 1532 vm_object_t object = NULL; 1533 struct thread *td = curthread; 1534 int docow, error, findspace, rv; 1535 boolean_t writecounted; 1536 1537 if (size == 0) 1538 return (0); 1539 1540 size = round_page(size); 1541 1542 if (map == &td->td_proc->p_vmspace->vm_map) { 1543 PROC_LOCK(td->td_proc); 1544 if (map->size + size > lim_cur(td->td_proc, RLIMIT_VMEM)) { 1545 PROC_UNLOCK(td->td_proc); 1546 return (ENOMEM); 1547 } 1548 if (racct_set(td->td_proc, RACCT_VMEM, map->size + size)) { 1549 PROC_UNLOCK(td->td_proc); 1550 return (ENOMEM); 1551 } 1552 if (!old_mlock && map->flags & MAP_WIREFUTURE) { 1553 if (ptoa(pmap_wired_count(map->pmap)) + size > 1554 lim_cur(td->td_proc, RLIMIT_MEMLOCK)) { 1555 racct_set_force(td->td_proc, RACCT_VMEM, 1556 map->size); 1557 PROC_UNLOCK(td->td_proc); 1558 return (ENOMEM); 1559 } 1560 error = racct_set(td->td_proc, RACCT_MEMLOCK, 1561 ptoa(pmap_wired_count(map->pmap)) + size); 1562 if (error != 0) { 1563 racct_set_force(td->td_proc, RACCT_VMEM, 1564 map->size); 1565 PROC_UNLOCK(td->td_proc); 1566 return (error); 1567 } 1568 } 1569 PROC_UNLOCK(td->td_proc); 1570 } 1571 1572 /* 1573 * We currently can only deal with page aligned file offsets. 1574 * The check is here rather than in the syscall because the 1575 * kernel calls this function internally for other mmaping 1576 * operations (such as in exec) and non-aligned offsets will 1577 * cause pmap inconsistencies...so we want to be sure to 1578 * disallow this in all cases. 1579 */ 1580 if (foff & PAGE_MASK) 1581 return (EINVAL); 1582 1583 if ((flags & MAP_FIXED) == 0) { 1584 fitit = TRUE; 1585 *addr = round_page(*addr); 1586 } else { 1587 if (*addr != trunc_page(*addr)) 1588 return (EINVAL); 1589 fitit = FALSE; 1590 } 1591 writecounted = FALSE; 1592 1593 /* 1594 * Lookup/allocate object. 1595 */ 1596 switch (handle_type) { 1597 case OBJT_DEVICE: 1598 error = vm_mmap_cdev(td, size, prot, &maxprot, &flags, 1599 handle, &foff, &object); 1600 break; 1601 case OBJT_VNODE: 1602 error = vm_mmap_vnode(td, size, prot, &maxprot, &flags, 1603 handle, &foff, &object, &writecounted); 1604 break; 1605 case OBJT_SWAP: 1606 error = vm_mmap_shm(td, size, prot, &maxprot, &flags, 1607 handle, foff, &object); 1608 break; 1609 case OBJT_DEFAULT: 1610 if (handle == NULL) { 1611 error = 0; 1612 break; 1613 } 1614 /* FALLTHROUGH */ 1615 default: 1616 error = EINVAL; 1617 break; 1618 } 1619 if (error) 1620 return (error); 1621 if (flags & MAP_ANON) { 1622 object = NULL; 1623 docow = 0; 1624 /* 1625 * Unnamed anonymous regions always start at 0. 1626 */ 1627 if (handle == 0) 1628 foff = 0; 1629 } else if (flags & MAP_PREFAULT_READ) 1630 docow = MAP_PREFAULT; 1631 else 1632 docow = MAP_PREFAULT_PARTIAL; 1633 1634 if ((flags & (MAP_ANON|MAP_SHARED)) == 0) 1635 docow |= MAP_COPY_ON_WRITE; 1636 if (flags & MAP_NOSYNC) 1637 docow |= MAP_DISABLE_SYNCER; 1638 if (flags & MAP_NOCORE) 1639 docow |= MAP_DISABLE_COREDUMP; 1640 /* Shared memory is also shared with children. */ 1641 if (flags & MAP_SHARED) 1642 docow |= MAP_INHERIT_SHARE; 1643 if (writecounted) 1644 docow |= MAP_VN_WRITECOUNT; 1645 if (flags & MAP_STACK) { 1646 if (object != NULL) 1647 return (EINVAL); 1648 docow |= MAP_STACK_GROWS_DOWN; 1649 } 1650 if ((flags & MAP_EXCL) != 0) 1651 docow |= MAP_CHECK_EXCL; 1652 1653 if (fitit) { 1654 if ((flags & MAP_ALIGNMENT_MASK) == MAP_ALIGNED_SUPER) 1655 findspace = VMFS_SUPER_SPACE; 1656 else if ((flags & MAP_ALIGNMENT_MASK) != 0) 1657 findspace = VMFS_ALIGNED_SPACE(flags >> 1658 MAP_ALIGNMENT_SHIFT); 1659 else 1660 findspace = VMFS_OPTIMAL_SPACE; 1661 rv = vm_map_find(map, object, foff, addr, size, 1662 #ifdef MAP_32BIT 1663 flags & MAP_32BIT ? MAP_32BIT_MAX_ADDR : 1664 #endif 1665 0, findspace, prot, maxprot, docow); 1666 } else { 1667 rv = vm_map_fixed(map, object, foff, *addr, size, 1668 prot, maxprot, docow); 1669 } 1670 1671 if (rv == KERN_SUCCESS) { 1672 /* 1673 * If the process has requested that all future mappings 1674 * be wired, then heed this. 1675 */ 1676 if (map->flags & MAP_WIREFUTURE) { 1677 vm_map_wire(map, *addr, *addr + size, 1678 VM_MAP_WIRE_USER | ((flags & MAP_STACK) ? 1679 VM_MAP_WIRE_HOLESOK : VM_MAP_WIRE_NOHOLES)); 1680 } 1681 } else { 1682 /* 1683 * If this mapping was accounted for in the vnode's 1684 * writecount, then undo that now. 1685 */ 1686 if (writecounted) 1687 vnode_pager_release_writecount(object, 0, size); 1688 /* 1689 * Lose the object reference. Will destroy the 1690 * object if it's an unnamed anonymous mapping 1691 * or named anonymous without other references. 1692 */ 1693 vm_object_deallocate(object); 1694 } 1695 return (vm_mmap_to_errno(rv)); 1696 } 1697 1698 /* 1699 * Translate a Mach VM return code to zero on success or the appropriate errno 1700 * on failure. 1701 */ 1702 int 1703 vm_mmap_to_errno(int rv) 1704 { 1705 1706 switch (rv) { 1707 case KERN_SUCCESS: 1708 return (0); 1709 case KERN_INVALID_ADDRESS: 1710 case KERN_NO_SPACE: 1711 return (ENOMEM); 1712 case KERN_PROTECTION_FAILURE: 1713 return (EACCES); 1714 default: 1715 return (EINVAL); 1716 } 1717 } 1718