1 /* $NetBSD: uvm_glue.c,v 1.97 2006/10/05 14:48:33 chs Exp $ */ 2 3 /* 4 * Copyright (c) 1997 Charles D. Cranor and Washington University. 5 * Copyright (c) 1991, 1993, The Regents of the University of California. 6 * 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * The Mach Operating System project at Carnegie-Mellon University. 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. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by Charles D. Cranor, 23 * Washington University, the University of California, Berkeley and 24 * its contributors. 25 * 4. Neither the name of the University nor the names of its contributors 26 * may be used to endorse or promote products derived from this software 27 * without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 39 * SUCH DAMAGE. 40 * 41 * @(#)vm_glue.c 8.6 (Berkeley) 1/5/94 42 * from: Id: uvm_glue.c,v 1.1.2.8 1998/02/07 01:16:54 chs Exp 43 * 44 * 45 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 46 * All rights reserved. 47 * 48 * Permission to use, copy, modify and distribute this software and 49 * its documentation is hereby granted, provided that both the copyright 50 * notice and this permission notice appear in all copies of the 51 * software, derivative works or modified versions, and any portions 52 * thereof, and that both notices appear in supporting documentation. 53 * 54 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 55 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 56 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 57 * 58 * Carnegie Mellon requests users of this software to return to 59 * 60 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 61 * School of Computer Science 62 * Carnegie Mellon University 63 * Pittsburgh PA 15213-3890 64 * 65 * any improvements or extensions that they make and grant Carnegie the 66 * rights to redistribute these changes. 67 */ 68 69 #include <sys/cdefs.h> 70 __KERNEL_RCSID(0, "$NetBSD: uvm_glue.c,v 1.97 2006/10/05 14:48:33 chs Exp $"); 71 72 #include "opt_coredump.h" 73 #include "opt_kgdb.h" 74 #include "opt_kstack.h" 75 #include "opt_uvmhist.h" 76 77 /* 78 * uvm_glue.c: glue functions 79 */ 80 81 #include <sys/param.h> 82 #include <sys/systm.h> 83 #include <sys/proc.h> 84 #include <sys/resourcevar.h> 85 #include <sys/buf.h> 86 #include <sys/user.h> 87 88 #include <uvm/uvm.h> 89 90 #include <machine/cpu.h> 91 92 /* 93 * local prototypes 94 */ 95 96 static void uvm_swapout(struct lwp *); 97 98 #define UVM_NUAREA_MAX 16 99 static vaddr_t uvm_uareas; 100 static int uvm_nuarea; 101 static struct simplelock uvm_uareas_slock = SIMPLELOCK_INITIALIZER; 102 #define UAREA_NEXTFREE(uarea) (*(vaddr_t *)(UAREA_TO_USER(uarea))) 103 104 static void uvm_uarea_free(vaddr_t); 105 106 /* 107 * XXXCDC: do these really belong here? 108 */ 109 110 /* 111 * uvm_kernacc: can the kernel access a region of memory 112 * 113 * - used only by /dev/kmem driver (mem.c) 114 */ 115 116 boolean_t 117 uvm_kernacc(caddr_t addr, size_t len, int rw) 118 { 119 boolean_t rv; 120 vaddr_t saddr, eaddr; 121 vm_prot_t prot = rw == B_READ ? VM_PROT_READ : VM_PROT_WRITE; 122 123 saddr = trunc_page((vaddr_t)addr); 124 eaddr = round_page((vaddr_t)addr + len); 125 vm_map_lock_read(kernel_map); 126 rv = uvm_map_checkprot(kernel_map, saddr, eaddr, prot); 127 vm_map_unlock_read(kernel_map); 128 129 return(rv); 130 } 131 132 #ifdef KGDB 133 /* 134 * Change protections on kernel pages from addr to addr+len 135 * (presumably so debugger can plant a breakpoint). 136 * 137 * We force the protection change at the pmap level. If we were 138 * to use vm_map_protect a change to allow writing would be lazily- 139 * applied meaning we would still take a protection fault, something 140 * we really don't want to do. It would also fragment the kernel 141 * map unnecessarily. We cannot use pmap_protect since it also won't 142 * enforce a write-enable request. Using pmap_enter is the only way 143 * we can ensure the change takes place properly. 144 */ 145 void 146 uvm_chgkprot(caddr_t addr, size_t len, int rw) 147 { 148 vm_prot_t prot; 149 paddr_t pa; 150 vaddr_t sva, eva; 151 152 prot = rw == B_READ ? VM_PROT_READ : VM_PROT_READ|VM_PROT_WRITE; 153 eva = round_page((vaddr_t)addr + len); 154 for (sva = trunc_page((vaddr_t)addr); sva < eva; sva += PAGE_SIZE) { 155 /* 156 * Extract physical address for the page. 157 */ 158 if (pmap_extract(pmap_kernel(), sva, &pa) == FALSE) 159 panic("chgkprot: invalid page"); 160 pmap_enter(pmap_kernel(), sva, pa, prot, PMAP_WIRED); 161 } 162 pmap_update(pmap_kernel()); 163 } 164 #endif 165 166 /* 167 * uvm_vslock: wire user memory for I/O 168 * 169 * - called from physio and sys___sysctl 170 * - XXXCDC: consider nuking this (or making it a macro?) 171 */ 172 173 int 174 uvm_vslock(struct vmspace *vs, void *addr, size_t len, vm_prot_t access_type) 175 { 176 struct vm_map *map; 177 vaddr_t start, end; 178 int error; 179 180 map = &vs->vm_map; 181 start = trunc_page((vaddr_t)addr); 182 end = round_page((vaddr_t)addr + len); 183 error = uvm_fault_wire(map, start, end, access_type, 0); 184 return error; 185 } 186 187 /* 188 * uvm_vsunlock: unwire user memory wired by uvm_vslock() 189 * 190 * - called from physio and sys___sysctl 191 * - XXXCDC: consider nuking this (or making it a macro?) 192 */ 193 194 void 195 uvm_vsunlock(struct vmspace *vs, void *addr, size_t len) 196 { 197 uvm_fault_unwire(&vs->vm_map, trunc_page((vaddr_t)addr), 198 round_page((vaddr_t)addr + len)); 199 } 200 201 /* 202 * uvm_proc_fork: fork a virtual address space 203 * 204 * - the address space is copied as per parent map's inherit values 205 */ 206 void 207 uvm_proc_fork(struct proc *p1, struct proc *p2, boolean_t shared) 208 { 209 210 if (shared == TRUE) { 211 p2->p_vmspace = NULL; 212 uvmspace_share(p1, p2); 213 } else { 214 p2->p_vmspace = uvmspace_fork(p1->p_vmspace); 215 } 216 217 cpu_proc_fork(p1, p2); 218 } 219 220 221 /* 222 * uvm_lwp_fork: fork a thread 223 * 224 * - a new "user" structure is allocated for the child process 225 * [filled in by MD layer...] 226 * - if specified, the child gets a new user stack described by 227 * stack and stacksize 228 * - NOTE: the kernel stack may be at a different location in the child 229 * process, and thus addresses of automatic variables may be invalid 230 * after cpu_lwp_fork returns in the child process. We do nothing here 231 * after cpu_lwp_fork returns. 232 * - XXXCDC: we need a way for this to return a failure value rather 233 * than just hang 234 */ 235 void 236 uvm_lwp_fork(struct lwp *l1, struct lwp *l2, void *stack, size_t stacksize, 237 void (*func)(void *), void *arg) 238 { 239 int error; 240 241 /* 242 * Wire down the U-area for the process, which contains the PCB 243 * and the kernel stack. Wired state is stored in l->l_flag's 244 * L_INMEM bit rather than in the vm_map_entry's wired count 245 * to prevent kernel_map fragmentation. If we reused a cached U-area, 246 * L_INMEM will already be set and we don't need to do anything. 247 * 248 * Note the kernel stack gets read/write accesses right off the bat. 249 */ 250 251 if ((l2->l_flag & L_INMEM) == 0) { 252 vaddr_t uarea = USER_TO_UAREA(l2->l_addr); 253 254 error = uvm_fault_wire(kernel_map, uarea, 255 uarea + USPACE, VM_PROT_READ | VM_PROT_WRITE, 0); 256 if (error) 257 panic("uvm_lwp_fork: uvm_fault_wire failed: %d", error); 258 #ifdef PMAP_UAREA 259 /* Tell the pmap this is a u-area mapping */ 260 PMAP_UAREA(uarea); 261 #endif 262 l2->l_flag |= L_INMEM; 263 } 264 265 #ifdef KSTACK_CHECK_MAGIC 266 /* 267 * fill stack with magic number 268 */ 269 kstack_setup_magic(l2); 270 #endif 271 272 /* 273 * cpu_lwp_fork() copy and update the pcb, and make the child ready 274 * to run. If this is a normal user fork, the child will exit 275 * directly to user mode via child_return() on its first time 276 * slice and will not return here. If this is a kernel thread, 277 * the specified entry point will be executed. 278 */ 279 cpu_lwp_fork(l1, l2, stack, stacksize, func, arg); 280 } 281 282 /* 283 * uvm_uarea_alloc: allocate a u-area 284 */ 285 286 boolean_t 287 uvm_uarea_alloc(vaddr_t *uaddrp) 288 { 289 vaddr_t uaddr; 290 291 #ifndef USPACE_ALIGN 292 #define USPACE_ALIGN 0 293 #endif 294 295 simple_lock(&uvm_uareas_slock); 296 if (uvm_nuarea > 0) { 297 uaddr = uvm_uareas; 298 uvm_uareas = UAREA_NEXTFREE(uaddr); 299 uvm_nuarea--; 300 simple_unlock(&uvm_uareas_slock); 301 *uaddrp = uaddr; 302 return TRUE; 303 } else { 304 simple_unlock(&uvm_uareas_slock); 305 *uaddrp = uvm_km_alloc(kernel_map, USPACE, USPACE_ALIGN, 306 UVM_KMF_PAGEABLE); 307 return FALSE; 308 } 309 } 310 311 /* 312 * uvm_uarea_free: free a u-area; never blocks 313 */ 314 315 static inline void 316 uvm_uarea_free(vaddr_t uaddr) 317 { 318 simple_lock(&uvm_uareas_slock); 319 UAREA_NEXTFREE(uaddr) = uvm_uareas; 320 uvm_uareas = uaddr; 321 uvm_nuarea++; 322 simple_unlock(&uvm_uareas_slock); 323 } 324 325 /* 326 * uvm_uarea_drain: return memory of u-areas over limit 327 * back to system 328 */ 329 330 void 331 uvm_uarea_drain(boolean_t empty) 332 { 333 int leave = empty ? 0 : UVM_NUAREA_MAX; 334 vaddr_t uaddr; 335 336 if (uvm_nuarea <= leave) 337 return; 338 339 simple_lock(&uvm_uareas_slock); 340 while(uvm_nuarea > leave) { 341 uaddr = uvm_uareas; 342 uvm_uareas = UAREA_NEXTFREE(uaddr); 343 uvm_nuarea--; 344 simple_unlock(&uvm_uareas_slock); 345 uvm_km_free(kernel_map, uaddr, USPACE, UVM_KMF_PAGEABLE); 346 simple_lock(&uvm_uareas_slock); 347 } 348 simple_unlock(&uvm_uareas_slock); 349 } 350 351 /* 352 * uvm_exit: exit a virtual address space 353 * 354 * - the process passed to us is a dead (pre-zombie) process; we 355 * are running on a different context now (the reaper). 356 * - borrow proc0's address space because freeing the vmspace 357 * of the dead process may block. 358 */ 359 360 void 361 uvm_proc_exit(struct proc *p) 362 { 363 struct lwp *l = curlwp; /* XXX */ 364 struct vmspace *ovm; 365 366 KASSERT(p == l->l_proc); 367 ovm = p->p_vmspace; 368 369 /* 370 * borrow proc0's address space. 371 */ 372 pmap_deactivate(l); 373 p->p_vmspace = proc0.p_vmspace; 374 pmap_activate(l); 375 376 uvmspace_free(ovm); 377 } 378 379 void 380 uvm_lwp_exit(struct lwp *l) 381 { 382 vaddr_t va = USER_TO_UAREA(l->l_addr); 383 384 l->l_flag &= ~L_INMEM; 385 uvm_uarea_free(va); 386 l->l_addr = NULL; 387 } 388 389 /* 390 * uvm_init_limit: init per-process VM limits 391 * 392 * - called for process 0 and then inherited by all others. 393 */ 394 395 void 396 uvm_init_limits(struct proc *p) 397 { 398 399 /* 400 * Set up the initial limits on process VM. Set the maximum 401 * resident set size to be all of (reasonably) available memory. 402 * This causes any single, large process to start random page 403 * replacement once it fills memory. 404 */ 405 406 p->p_rlimit[RLIMIT_STACK].rlim_cur = DFLSSIZ; 407 p->p_rlimit[RLIMIT_STACK].rlim_max = maxsmap; 408 p->p_rlimit[RLIMIT_DATA].rlim_cur = DFLDSIZ; 409 p->p_rlimit[RLIMIT_DATA].rlim_max = maxdmap; 410 p->p_rlimit[RLIMIT_RSS].rlim_cur = ptoa(uvmexp.free); 411 } 412 413 #ifdef DEBUG 414 int enableswap = 1; 415 int swapdebug = 0; 416 #define SDB_FOLLOW 1 417 #define SDB_SWAPIN 2 418 #define SDB_SWAPOUT 4 419 #endif 420 421 /* 422 * uvm_swapin: swap in an lwp's u-area. 423 */ 424 425 void 426 uvm_swapin(struct lwp *l) 427 { 428 vaddr_t addr; 429 int s, error; 430 431 addr = USER_TO_UAREA(l->l_addr); 432 /* make L_INMEM true */ 433 error = uvm_fault_wire(kernel_map, addr, addr + USPACE, 434 VM_PROT_READ | VM_PROT_WRITE, 0); 435 if (error) { 436 panic("uvm_swapin: rewiring stack failed: %d", error); 437 } 438 439 /* 440 * Some architectures need to be notified when the user area has 441 * moved to new physical page(s) (e.g. see mips/mips/vm_machdep.c). 442 */ 443 cpu_swapin(l); 444 SCHED_LOCK(s); 445 if (l->l_stat == LSRUN) 446 setrunqueue(l); 447 l->l_flag |= L_INMEM; 448 SCHED_UNLOCK(s); 449 l->l_swtime = 0; 450 ++uvmexp.swapins; 451 } 452 453 /* 454 * uvm_scheduler: process zero main loop 455 * 456 * - attempt to swapin every swaped-out, runnable process in order of 457 * priority. 458 * - if not enough memory, wake the pagedaemon and let it clear space. 459 */ 460 461 void 462 uvm_scheduler(void) 463 { 464 struct lwp *l, *ll; 465 int pri; 466 int ppri; 467 468 loop: 469 #ifdef DEBUG 470 while (!enableswap) 471 tsleep(&proc0, PVM, "noswap", 0); 472 #endif 473 ll = NULL; /* process to choose */ 474 ppri = INT_MIN; /* its priority */ 475 proclist_lock_read(); 476 477 LIST_FOREACH(l, &alllwp, l_list) { 478 /* is it a runnable swapped out process? */ 479 if (l->l_stat == LSRUN && (l->l_flag & L_INMEM) == 0) { 480 pri = l->l_swtime + l->l_slptime - 481 (l->l_proc->p_nice - NZERO) * 8; 482 if (pri > ppri) { /* higher priority? remember it. */ 483 ll = l; 484 ppri = pri; 485 } 486 } 487 } 488 /* 489 * XXXSMP: possible unlock/sleep race between here and the 490 * "scheduler" tsleep below.. 491 */ 492 proclist_unlock_read(); 493 494 #ifdef DEBUG 495 if (swapdebug & SDB_FOLLOW) 496 printf("scheduler: running, procp %p pri %d\n", ll, ppri); 497 #endif 498 /* 499 * Nothing to do, back to sleep 500 */ 501 if ((l = ll) == NULL) { 502 tsleep(&proc0, PVM, "scheduler", 0); 503 goto loop; 504 } 505 506 /* 507 * we have found swapped out process which we would like to bring 508 * back in. 509 * 510 * XXX: this part is really bogus cuz we could deadlock on memory 511 * despite our feeble check 512 */ 513 if (uvmexp.free > atop(USPACE)) { 514 #ifdef DEBUG 515 if (swapdebug & SDB_SWAPIN) 516 printf("swapin: pid %d(%s)@%p, pri %d free %d\n", 517 l->l_proc->p_pid, l->l_proc->p_comm, l->l_addr, ppri, uvmexp.free); 518 #endif 519 uvm_swapin(l); 520 goto loop; 521 } 522 /* 523 * not enough memory, jab the pageout daemon and wait til the coast 524 * is clear 525 */ 526 #ifdef DEBUG 527 if (swapdebug & SDB_FOLLOW) 528 printf("scheduler: no room for pid %d(%s), free %d\n", 529 l->l_proc->p_pid, l->l_proc->p_comm, uvmexp.free); 530 #endif 531 uvm_wait("schedpwait"); 532 #ifdef DEBUG 533 if (swapdebug & SDB_FOLLOW) 534 printf("scheduler: room again, free %d\n", uvmexp.free); 535 #endif 536 goto loop; 537 } 538 539 /* 540 * swappable: is LWP "l" swappable? 541 */ 542 543 #define swappable(l) \ 544 (((l)->l_flag & (L_INMEM)) && \ 545 ((((l)->l_proc->p_flag) & (P_SYSTEM | P_WEXIT)) == 0) && \ 546 (l)->l_holdcnt == 0) 547 548 /* 549 * swapout_threads: find threads that can be swapped and unwire their 550 * u-areas. 551 * 552 * - called by the pagedaemon 553 * - try and swap at least one processs 554 * - processes that are sleeping or stopped for maxslp or more seconds 555 * are swapped... otherwise the longest-sleeping or stopped process 556 * is swapped, otherwise the longest resident process... 557 */ 558 559 void 560 uvm_swapout_threads(void) 561 { 562 struct lwp *l; 563 struct lwp *outl, *outl2; 564 int outpri, outpri2; 565 int didswap = 0; 566 extern int maxslp; 567 /* XXXCDC: should move off to uvmexp. or uvm., also in uvm_meter */ 568 569 #ifdef DEBUG 570 if (!enableswap) 571 return; 572 #endif 573 574 /* 575 * outl/outpri : stop/sleep thread with largest sleeptime < maxslp 576 * outl2/outpri2: the longest resident thread (its swap time) 577 */ 578 outl = outl2 = NULL; 579 outpri = outpri2 = 0; 580 proclist_lock_read(); 581 LIST_FOREACH(l, &alllwp, l_list) { 582 KASSERT(l->l_proc != NULL); 583 if (!swappable(l)) 584 continue; 585 switch (l->l_stat) { 586 case LSONPROC: 587 continue; 588 589 case LSRUN: 590 if (l->l_swtime > outpri2) { 591 outl2 = l; 592 outpri2 = l->l_swtime; 593 } 594 continue; 595 596 case LSSLEEP: 597 case LSSTOP: 598 if (l->l_slptime >= maxslp) { 599 uvm_swapout(l); 600 didswap++; 601 } else if (l->l_slptime > outpri) { 602 outl = l; 603 outpri = l->l_slptime; 604 } 605 continue; 606 } 607 } 608 proclist_unlock_read(); 609 610 /* 611 * If we didn't get rid of any real duds, toss out the next most 612 * likely sleeping/stopped or running candidate. We only do this 613 * if we are real low on memory since we don't gain much by doing 614 * it (USPACE bytes). 615 */ 616 if (didswap == 0 && uvmexp.free <= atop(round_page(USPACE))) { 617 if ((l = outl) == NULL) 618 l = outl2; 619 #ifdef DEBUG 620 if (swapdebug & SDB_SWAPOUT) 621 printf("swapout_threads: no duds, try procp %p\n", l); 622 #endif 623 if (l) 624 uvm_swapout(l); 625 } 626 } 627 628 /* 629 * uvm_swapout: swap out lwp "l" 630 * 631 * - currently "swapout" means "unwire U-area" and "pmap_collect()" 632 * the pmap. 633 * - XXXCDC: should deactivate all process' private anonymous memory 634 */ 635 636 static void 637 uvm_swapout(struct lwp *l) 638 { 639 vaddr_t addr; 640 int s; 641 struct proc *p = l->l_proc; 642 643 #ifdef DEBUG 644 if (swapdebug & SDB_SWAPOUT) 645 printf("swapout: lid %d.%d(%s)@%p, stat %x pri %d free %d\n", 646 p->p_pid, l->l_lid, p->p_comm, l->l_addr, l->l_stat, 647 l->l_slptime, uvmexp.free); 648 #endif 649 650 /* 651 * Mark it as (potentially) swapped out. 652 */ 653 SCHED_LOCK(s); 654 if (l->l_stat == LSONPROC) { 655 KDASSERT(l->l_cpu != curcpu()); 656 SCHED_UNLOCK(s); 657 return; 658 } 659 l->l_flag &= ~L_INMEM; 660 if (l->l_stat == LSRUN) 661 remrunqueue(l); 662 SCHED_UNLOCK(s); 663 l->l_swtime = 0; 664 p->p_stats->p_ru.ru_nswap++; 665 ++uvmexp.swapouts; 666 667 /* 668 * Do any machine-specific actions necessary before swapout. 669 * This can include saving floating point state, etc. 670 */ 671 cpu_swapout(l); 672 673 /* 674 * Unwire the to-be-swapped process's user struct and kernel stack. 675 */ 676 addr = USER_TO_UAREA(l->l_addr); 677 uvm_fault_unwire(kernel_map, addr, addr + USPACE); /* !L_INMEM */ 678 pmap_collect(vm_map_pmap(&p->p_vmspace->vm_map)); 679 } 680 681 #ifdef COREDUMP 682 /* 683 * uvm_coredump_walkmap: walk a process's map for the purpose of dumping 684 * a core file. 685 */ 686 687 int 688 uvm_coredump_walkmap(struct proc *p, void *iocookie, 689 int (*func)(struct proc *, void *, struct uvm_coredump_state *), 690 void *cookie) 691 { 692 struct uvm_coredump_state state; 693 struct vmspace *vm = p->p_vmspace; 694 struct vm_map *map = &vm->vm_map; 695 struct vm_map_entry *entry; 696 int error; 697 698 entry = NULL; 699 vm_map_lock_read(map); 700 state.end = 0; 701 for (;;) { 702 if (entry == NULL) 703 entry = map->header.next; 704 else if (!uvm_map_lookup_entry(map, state.end, &entry)) 705 entry = entry->next; 706 if (entry == &map->header) 707 break; 708 709 state.cookie = cookie; 710 if (state.end > entry->start) { 711 state.start = state.end; 712 } else { 713 state.start = entry->start; 714 } 715 state.realend = entry->end; 716 state.end = entry->end; 717 state.prot = entry->protection; 718 state.flags = 0; 719 720 /* 721 * Dump the region unless one of the following is true: 722 * 723 * (1) the region has neither object nor amap behind it 724 * (ie. it has never been accessed). 725 * 726 * (2) the region has no amap and is read-only 727 * (eg. an executable text section). 728 * 729 * (3) the region's object is a device. 730 * 731 * (4) the region is unreadable by the process. 732 */ 733 734 KASSERT(!UVM_ET_ISSUBMAP(entry)); 735 KASSERT(state.start < VM_MAXUSER_ADDRESS); 736 KASSERT(state.end <= VM_MAXUSER_ADDRESS); 737 if (entry->object.uvm_obj == NULL && 738 entry->aref.ar_amap == NULL) { 739 state.realend = state.start; 740 } else if ((entry->protection & VM_PROT_WRITE) == 0 && 741 entry->aref.ar_amap == NULL) { 742 state.realend = state.start; 743 } else if (entry->object.uvm_obj != NULL && 744 UVM_OBJ_IS_DEVICE(entry->object.uvm_obj)) { 745 state.realend = state.start; 746 } else if ((entry->protection & VM_PROT_READ) == 0) { 747 state.realend = state.start; 748 } else { 749 if (state.start >= (vaddr_t)vm->vm_maxsaddr) 750 state.flags |= UVM_COREDUMP_STACK; 751 752 /* 753 * If this an anonymous entry, only dump instantiated 754 * pages. 755 */ 756 if (entry->object.uvm_obj == NULL) { 757 vaddr_t end; 758 759 amap_lock(entry->aref.ar_amap); 760 for (end = state.start; 761 end < state.end; end += PAGE_SIZE) { 762 struct vm_anon *anon; 763 anon = amap_lookup(&entry->aref, 764 end - entry->start); 765 /* 766 * If we have already encountered an 767 * uninstantiated page, stop at the 768 * first instantied page. 769 */ 770 if (anon != NULL && 771 state.realend != state.end) { 772 state.end = end; 773 break; 774 } 775 776 /* 777 * If this page is the first 778 * uninstantiated page, mark this as 779 * the real ending point. Continue to 780 * counting uninstantiated pages. 781 */ 782 if (anon == NULL && 783 state.realend == state.end) { 784 state.realend = end; 785 } 786 } 787 amap_unlock(entry->aref.ar_amap); 788 } 789 } 790 791 792 vm_map_unlock_read(map); 793 error = (*func)(p, iocookie, &state); 794 if (error) 795 return (error); 796 vm_map_lock_read(map); 797 } 798 vm_map_unlock_read(map); 799 800 return (0); 801 } 802 #endif /* COREDUMP */ 803