vm_machdep.c revision 13915
1/*- 2 * Copyright (c) 1982, 1986 The Regents of the University of California. 3 * Copyright (c) 1989, 1990 William Jolitz 4 * Copyright (c) 1994 John Dyson 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * the Systems Programming Group of the University of Utah Computer 9 * Science Department, and William Jolitz. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * from: @(#)vm_machdep.c 7.3 (Berkeley) 5/13/91 40 * Utah $Hdr: vm_machdep.c 1.16.1.1 89/06/23$ 41 * $Id: vm_machdep.c,v 1.55 1996/02/04 22:09:12 dyson Exp $ 42 */ 43 44#include "npx.h" 45#include "opt_bounce.h" 46 47#include <sys/param.h> 48#include <sys/systm.h> 49#include <sys/proc.h> 50#include <sys/malloc.h> 51#include <sys/buf.h> 52#include <sys/vnode.h> 53#include <sys/vmmeter.h> 54 55#include <machine/clock.h> 56#include <machine/cpu.h> 57#include <machine/md_var.h> 58 59#include <vm/vm.h> 60#include <vm/vm_param.h> 61#include <vm/vm_prot.h> 62#include <vm/lock.h> 63#include <vm/vm_kern.h> 64#include <vm/vm_page.h> 65#include <vm/vm_map.h> 66#include <vm/vm_extern.h> 67 68#include <sys/user.h> 69 70#include <i386/isa/isa.h> 71 72#ifdef BOUNCE_BUFFERS 73static vm_offset_t 74 vm_bounce_kva __P((int size, int waitok)); 75static void vm_bounce_kva_free __P((vm_offset_t addr, vm_offset_t size, 76 int now)); 77static vm_offset_t 78 vm_bounce_page_find __P((int count)); 79static void vm_bounce_page_free __P((vm_offset_t pa, int count)); 80 81static volatile int kvasfreecnt; 82 83caddr_t bouncememory; 84int bouncepages; 85static int bpwait; 86static vm_offset_t *bouncepa; 87static int bmwait, bmfreeing; 88 89#define BITS_IN_UNSIGNED (8*sizeof(unsigned)) 90static int bounceallocarraysize; 91static unsigned *bounceallocarray; 92static int bouncefree; 93 94#define SIXTEENMEG (4096*4096) 95#define MAXBKVA 1024 96int maxbkva = MAXBKVA*NBPG; 97 98/* special list that can be used at interrupt time for eventual kva free */ 99static struct kvasfree { 100 vm_offset_t addr; 101 vm_offset_t size; 102} kvaf[MAXBKVA]; 103 104/* 105 * get bounce buffer pages (count physically contiguous) 106 * (only 1 inplemented now) 107 */ 108static vm_offset_t 109vm_bounce_page_find(count) 110 int count; 111{ 112 int bit; 113 int s,i; 114 115 if (count != 1) 116 panic("vm_bounce_page_find -- no support for > 1 page yet!!!"); 117 118 s = splbio(); 119retry: 120 for (i = 0; i < bounceallocarraysize; i++) { 121 if (bounceallocarray[i] != 0xffffffff) { 122 bit = ffs(~bounceallocarray[i]); 123 if (bit) { 124 bounceallocarray[i] |= 1 << (bit - 1) ; 125 bouncefree -= count; 126 splx(s); 127 return bouncepa[(i * BITS_IN_UNSIGNED + (bit - 1))]; 128 } 129 } 130 } 131 bpwait = 1; 132 tsleep((caddr_t) &bounceallocarray, PRIBIO, "bncwai", 0); 133 goto retry; 134} 135 136static void 137vm_bounce_kva_free(addr, size, now) 138 vm_offset_t addr; 139 vm_offset_t size; 140 int now; 141{ 142 int s = splbio(); 143 kvaf[kvasfreecnt].addr = addr; 144 kvaf[kvasfreecnt].size = size; 145 ++kvasfreecnt; 146 if( now) { 147 /* 148 * this will do wakeups 149 */ 150 vm_bounce_kva(0,0); 151 } else { 152 if (bmwait) { 153 /* 154 * if anyone is waiting on the bounce-map, then wakeup 155 */ 156 wakeup((caddr_t) io_map); 157 bmwait = 0; 158 } 159 } 160 splx(s); 161} 162 163/* 164 * free count bounce buffer pages 165 */ 166static void 167vm_bounce_page_free(pa, count) 168 vm_offset_t pa; 169 int count; 170{ 171 int allocindex; 172 int index; 173 int bit; 174 175 if (count != 1) 176 panic("vm_bounce_page_free -- no support for > 1 page yet!!!"); 177 178 for(index=0;index<bouncepages;index++) { 179 if( pa == bouncepa[index]) 180 break; 181 } 182 183 if( index == bouncepages) 184 panic("vm_bounce_page_free: invalid bounce buffer"); 185 186 allocindex = index / BITS_IN_UNSIGNED; 187 bit = index % BITS_IN_UNSIGNED; 188 189 bounceallocarray[allocindex] &= ~(1 << bit); 190 191 bouncefree += count; 192 if (bpwait) { 193 bpwait = 0; 194 wakeup((caddr_t) &bounceallocarray); 195 } 196} 197 198/* 199 * allocate count bounce buffer kva pages 200 */ 201static vm_offset_t 202vm_bounce_kva(size, waitok) 203 int size; 204 int waitok; 205{ 206 int i; 207 vm_offset_t kva = 0; 208 vm_offset_t off; 209 int s = splbio(); 210more: 211 if (!bmfreeing && kvasfreecnt) { 212 bmfreeing = 1; 213 for (i = 0; i < kvasfreecnt; i++) { 214 for(off=0;off<kvaf[i].size;off+=NBPG) { 215 pmap_kremove( kvaf[i].addr + off); 216 } 217 kmem_free_wakeup(io_map, kvaf[i].addr, 218 kvaf[i].size); 219 } 220 kvasfreecnt = 0; 221 bmfreeing = 0; 222 if( bmwait) { 223 bmwait = 0; 224 wakeup( (caddr_t) io_map); 225 } 226 } 227 228 if( size == 0) { 229 splx(s); 230 return NULL; 231 } 232 233 if ((kva = kmem_alloc_pageable(io_map, size)) == 0) { 234 if( !waitok) { 235 splx(s); 236 return NULL; 237 } 238 bmwait = 1; 239 tsleep((caddr_t) io_map, PRIBIO, "bmwait", 0); 240 goto more; 241 } 242 splx(s); 243 return kva; 244} 245 246/* 247 * same as vm_bounce_kva -- but really allocate (but takes pages as arg) 248 */ 249vm_offset_t 250vm_bounce_kva_alloc(count) 251int count; 252{ 253 int i; 254 vm_offset_t kva; 255 vm_offset_t pa; 256 if( bouncepages == 0) { 257 kva = (vm_offset_t) malloc(count*NBPG, M_TEMP, M_WAITOK); 258 return kva; 259 } 260 kva = vm_bounce_kva(count*NBPG, 1); 261 for(i=0;i<count;i++) { 262 pa = vm_bounce_page_find(1); 263 pmap_kenter(kva + i * NBPG, pa); 264 } 265 return kva; 266} 267 268/* 269 * same as vm_bounce_kva_free -- but really free 270 */ 271void 272vm_bounce_kva_alloc_free(kva, count) 273 vm_offset_t kva; 274 int count; 275{ 276 int i; 277 vm_offset_t pa; 278 if( bouncepages == 0) { 279 free((caddr_t) kva, M_TEMP); 280 return; 281 } 282 for(i = 0; i < count; i++) { 283 pa = pmap_kextract(kva + i * NBPG); 284 vm_bounce_page_free(pa, 1); 285 } 286 vm_bounce_kva_free(kva, count*NBPG, 0); 287} 288 289/* 290 * do the things necessary to the struct buf to implement 291 * bounce buffers... inserted before the disk sort 292 */ 293void 294vm_bounce_alloc(bp) 295 struct buf *bp; 296{ 297 int countvmpg; 298 vm_offset_t vastart, vaend; 299 vm_offset_t vapstart, vapend; 300 vm_offset_t va, kva; 301 vm_offset_t pa; 302 int dobounceflag = 0; 303 int i; 304 305 if (bouncepages == 0) 306 return; 307 308 if (bp->b_flags & B_BOUNCE) { 309 printf("vm_bounce_alloc: called recursively???\n"); 310 return; 311 } 312 313 if (bp->b_bufsize < bp->b_bcount) { 314 printf( 315 "vm_bounce_alloc: b_bufsize(0x%lx) < b_bcount(0x%lx) !!\n", 316 bp->b_bufsize, bp->b_bcount); 317 panic("vm_bounce_alloc"); 318 } 319 320/* 321 * This is not really necessary 322 * if( bp->b_bufsize != bp->b_bcount) { 323 * printf("size: %d, count: %d\n", bp->b_bufsize, bp->b_bcount); 324 * } 325 */ 326 327 328 vastart = (vm_offset_t) bp->b_data; 329 vaend = (vm_offset_t) bp->b_data + bp->b_bufsize; 330 331 vapstart = trunc_page(vastart); 332 vapend = round_page(vaend); 333 countvmpg = (vapend - vapstart) / NBPG; 334 335/* 336 * if any page is above 16MB, then go into bounce-buffer mode 337 */ 338 va = vapstart; 339 for (i = 0; i < countvmpg; i++) { 340 pa = pmap_kextract(va); 341 if (pa >= SIXTEENMEG) 342 ++dobounceflag; 343 if( pa == 0) 344 panic("vm_bounce_alloc: Unmapped page"); 345 va += NBPG; 346 } 347 if (dobounceflag == 0) 348 return; 349 350 if (bouncepages < dobounceflag) 351 panic("Not enough bounce buffers!!!"); 352 353/* 354 * allocate a replacement kva for b_addr 355 */ 356 kva = vm_bounce_kva(countvmpg*NBPG, 1); 357#if 0 358 printf("%s: vapstart: %x, vapend: %x, countvmpg: %d, kva: %x ", 359 (bp->b_flags & B_READ) ? "read":"write", 360 vapstart, vapend, countvmpg, kva); 361#endif 362 va = vapstart; 363 for (i = 0; i < countvmpg; i++) { 364 pa = pmap_kextract(va); 365 if (pa >= SIXTEENMEG) { 366 /* 367 * allocate a replacement page 368 */ 369 vm_offset_t bpa = vm_bounce_page_find(1); 370 pmap_kenter(kva + (NBPG * i), bpa); 371#if 0 372 printf("r(%d): (%x,%x,%x) ", i, va, pa, bpa); 373#endif 374 /* 375 * if we are writing, the copy the data into the page 376 */ 377 if ((bp->b_flags & B_READ) == 0) { 378 bcopy((caddr_t) va, (caddr_t) kva + (NBPG * i), NBPG); 379 } 380 } else { 381 /* 382 * use original page 383 */ 384 pmap_kenter(kva + (NBPG * i), pa); 385 } 386 va += NBPG; 387 } 388 389/* 390 * flag the buffer as being bounced 391 */ 392 bp->b_flags |= B_BOUNCE; 393/* 394 * save the original buffer kva 395 */ 396 bp->b_savekva = bp->b_data; 397/* 398 * put our new kva into the buffer (offset by original offset) 399 */ 400 bp->b_data = (caddr_t) (((vm_offset_t) kva) | 401 ((vm_offset_t) bp->b_savekva & (NBPG - 1))); 402#if 0 403 printf("b_savekva: %x, newva: %x\n", bp->b_savekva, bp->b_data); 404#endif 405 return; 406} 407 408/* 409 * hook into biodone to free bounce buffer 410 */ 411void 412vm_bounce_free(bp) 413 struct buf *bp; 414{ 415 int i; 416 vm_offset_t origkva, bouncekva, bouncekvaend; 417 418/* 419 * if this isn't a bounced buffer, then just return 420 */ 421 if ((bp->b_flags & B_BOUNCE) == 0) 422 return; 423 424/* 425 * This check is not necessary 426 * if (bp->b_bufsize != bp->b_bcount) { 427 * printf("vm_bounce_free: b_bufsize=%d, b_bcount=%d\n", 428 * bp->b_bufsize, bp->b_bcount); 429 * } 430 */ 431 432 origkva = (vm_offset_t) bp->b_savekva; 433 bouncekva = (vm_offset_t) bp->b_data; 434/* 435 printf("free: %d ", bp->b_bufsize); 436*/ 437 438/* 439 * check every page in the kva space for b_addr 440 */ 441 for (i = 0; i < bp->b_bufsize; ) { 442 vm_offset_t mybouncepa; 443 vm_offset_t copycount; 444 445 copycount = round_page(bouncekva + 1) - bouncekva; 446 mybouncepa = pmap_kextract(trunc_page(bouncekva)); 447 448/* 449 * if this is a bounced pa, then process as one 450 */ 451 if ( mybouncepa != pmap_kextract( trunc_page( origkva))) { 452 vm_offset_t tocopy = copycount; 453 if (i + tocopy > bp->b_bufsize) 454 tocopy = bp->b_bufsize - i; 455/* 456 * if this is a read, then copy from bounce buffer into original buffer 457 */ 458 if (bp->b_flags & B_READ) 459 bcopy((caddr_t) bouncekva, (caddr_t) origkva, tocopy); 460/* 461 * free the bounce allocation 462 */ 463 464/* 465 printf("(kva: %x, pa: %x)", bouncekva, mybouncepa); 466*/ 467 vm_bounce_page_free(mybouncepa, 1); 468 } 469 470 origkva += copycount; 471 bouncekva += copycount; 472 i += copycount; 473 } 474 475/* 476 printf("\n"); 477*/ 478/* 479 * add the old kva into the "to free" list 480 */ 481 482 bouncekva= trunc_page((vm_offset_t) bp->b_data); 483 bouncekvaend= round_page((vm_offset_t)bp->b_data + bp->b_bufsize); 484 485/* 486 printf("freeva: %d\n", (bouncekvaend - bouncekva) / NBPG); 487*/ 488 vm_bounce_kva_free( bouncekva, (bouncekvaend - bouncekva), 0); 489 bp->b_data = bp->b_savekva; 490 bp->b_savekva = 0; 491 bp->b_flags &= ~B_BOUNCE; 492 493 return; 494} 495 496 497/* 498 * init the bounce buffer system 499 */ 500void 501vm_bounce_init() 502{ 503 int i; 504 505 kvasfreecnt = 0; 506 507 if (bouncepages == 0) 508 return; 509 510 bounceallocarraysize = (bouncepages + BITS_IN_UNSIGNED - 1) / BITS_IN_UNSIGNED; 511 bounceallocarray = malloc(bounceallocarraysize * sizeof(unsigned), M_TEMP, M_NOWAIT); 512 513 if (!bounceallocarray) 514 panic("Cannot allocate bounce resource array"); 515 516 bouncepa = malloc(bouncepages * sizeof(vm_offset_t), M_TEMP, M_NOWAIT); 517 if (!bouncepa) 518 panic("Cannot allocate physical memory array"); 519 520 for(i=0;i<bounceallocarraysize;i++) { 521 bounceallocarray[i] = 0xffffffff; 522 } 523 524 for(i=0;i<bouncepages;i++) { 525 vm_offset_t pa; 526 if( (pa = pmap_kextract((vm_offset_t) bouncememory + i * NBPG)) >= SIXTEENMEG) 527 panic("bounce memory out of range"); 528 if( pa == 0) 529 panic("bounce memory not resident"); 530 bouncepa[i] = pa; 531 bounceallocarray[i/(8*sizeof(int))] &= ~(1<<(i%(8*sizeof(int)))); 532 } 533 bouncefree = bouncepages; 534 535} 536#endif /* BOUNCE_BUFFERS */ 537 538/* 539 * quick version of vm_fault 540 */ 541void 542vm_fault_quick(v, prot) 543 caddr_t v; 544 int prot; 545{ 546 if (prot & VM_PROT_WRITE) 547 subyte(v, fubyte(v)); 548 else 549 fubyte(v); 550} 551 552/* 553 * Finish a fork operation, with process p2 nearly set up. 554 * Copy and update the kernel stack and pcb, making the child 555 * ready to run, and marking it so that it can return differently 556 * than the parent. Returns 1 in the child process, 0 in the parent. 557 * We currently double-map the user area so that the stack is at the same 558 * address in each process; in the future we will probably relocate 559 * the frame pointers on the stack after copying. 560 */ 561int 562cpu_fork(p1, p2) 563 register struct proc *p1, *p2; 564{ 565 struct pcb *pcb2 = &p2->p_addr->u_pcb; 566 int sp, offset; 567 568 /* 569 * Copy pcb and stack from proc p1 to p2. 570 * We do this as cheaply as possible, copying only the active 571 * part of the stack. The stack and pcb need to agree; 572 * this is tricky, as the final pcb is constructed by savectx, 573 * but its frame isn't yet on the stack when the stack is copied. 574 * This should be done differently, with a single call 575 * that copies and updates the pcb+stack, 576 * replacing the bcopy and savectx. 577 */ 578 579 __asm __volatile("movl %%esp,%0" : "=r" (sp)); 580 offset = sp - (int)kstack; 581 582 bcopy((caddr_t)kstack + offset, (caddr_t)p2->p_addr + offset, 583 (unsigned) ctob(UPAGES) - offset); 584 p2->p_md.md_regs = p1->p_md.md_regs; 585 586 *pcb2 = p1->p_addr->u_pcb; 587 pcb2->pcb_cr3 = vtophys(p2->p_vmspace->vm_pmap.pm_pdir); 588 589 /* 590 * Returns (0) in parent, (1) in child. 591 */ 592 return (savectx(pcb2)); 593} 594 595void 596cpu_exit(p) 597 register struct proc *p; 598{ 599 600#if NNPX > 0 601 npxexit(p); 602#endif /* NNPX */ 603 cnt.v_swtch++; 604 cpu_switch(p); 605 panic("cpu_exit"); 606} 607 608void 609cpu_wait(p) 610 struct proc *p; 611{ 612 /* drop per-process resources */ 613 pmap_qremove((vm_offset_t) p->p_addr, UPAGES); 614 kmem_free(u_map, (vm_offset_t)p->p_addr, ctob(UPAGES)); 615 vmspace_free(p->p_vmspace); 616} 617 618/* 619 * Dump the machine specific header information at the start of a core dump. 620 */ 621int 622cpu_coredump(p, vp, cred) 623 struct proc *p; 624 struct vnode *vp; 625 struct ucred *cred; 626{ 627 628 return (vn_rdwr(UIO_WRITE, vp, (caddr_t) p->p_addr, ctob(UPAGES), 629 (off_t)0, UIO_SYSSPACE, IO_NODELOCKED|IO_UNIT, cred, (int *)NULL, 630 p)); 631} 632 633#ifdef notyet 634static void 635setredzone(pte, vaddr) 636 u_short *pte; 637 caddr_t vaddr; 638{ 639/* eventually do this by setting up an expand-down stack segment 640 for ss0: selector, allowing stack access down to top of u. 641 this means though that protection violations need to be handled 642 thru a double fault exception that must do an integral task 643 switch to a known good context, within which a dump can be 644 taken. a sensible scheme might be to save the initial context 645 used by sched (that has physical memory mapped 1:1 at bottom) 646 and take the dump while still in mapped mode */ 647} 648#endif 649 650/* 651 * Convert kernel VA to physical address 652 */ 653u_long 654kvtop(void *addr) 655{ 656 vm_offset_t va; 657 658 va = pmap_kextract((vm_offset_t)addr); 659 if (va == 0) 660 panic("kvtop: zero page frame"); 661 return((int)va); 662} 663 664/* 665 * Map an IO request into kernel virtual address space. 666 * 667 * All requests are (re)mapped into kernel VA space. 668 * Notice that we use b_bufsize for the size of the buffer 669 * to be mapped. b_bcount might be modified by the driver. 670 */ 671void 672vmapbuf(bp) 673 register struct buf *bp; 674{ 675 register int npf; 676 register caddr_t addr; 677 int off; 678 vm_offset_t kva; 679 vm_offset_t pa; 680 681 if ((bp->b_flags & B_PHYS) == 0) 682 panic("vmapbuf"); 683 684 /* 685 * this is the kva that is to be used for 686 * the temporary kernel mapping 687 */ 688 kva = (vm_offset_t) bp->b_saveaddr; 689 690 for (addr = (caddr_t)trunc_page(bp->b_data); 691 addr < bp->b_data + bp->b_bufsize; 692 addr += PAGE_SIZE) { 693 694/* 695 * do the vm_fault if needed, do the copy-on-write thing when 696 * reading stuff off device into memory. 697 */ 698 vm_fault_quick(addr, 699 (bp->b_flags&B_READ)?(VM_PROT_READ|VM_PROT_WRITE):VM_PROT_READ); 700 pa = pmap_kextract((vm_offset_t) addr); 701 if (pa == 0) 702 panic("vmapbuf: page not present"); 703/* 704 * hold the data page 705 */ 706#ifdef DIAGNOSTIC 707 if( VM_PAGE_TO_PHYS(PHYS_TO_VM_PAGE(pa)) != pa) 708 panic("vmapbuf: confused PHYS_TO_VM_PAGE mapping"); 709#endif 710 vm_page_hold(PHYS_TO_VM_PAGE(pa)); 711 } 712 713 addr = bp->b_saveaddr = bp->b_data; 714 off = (int)addr & PGOFSET; 715 npf = btoc(round_page(bp->b_bufsize + off)); 716 bp->b_data = (caddr_t) (kva + off); 717 while (npf--) { 718 pa = pmap_kextract((vm_offset_t)addr); 719 if (pa == 0) 720 panic("vmapbuf: null page frame"); 721 pmap_kenter(kva, trunc_page(pa)); 722 addr += PAGE_SIZE; 723 kva += PAGE_SIZE; 724 } 725} 726 727/* 728 * Free the io map PTEs associated with this IO operation. 729 * We also invalidate the TLB entries and restore the original b_addr. 730 */ 731void 732vunmapbuf(bp) 733 register struct buf *bp; 734{ 735 register caddr_t addr; 736 vm_offset_t pa; 737 738 if ((bp->b_flags & B_PHYS) == 0) 739 panic("vunmapbuf"); 740 741 for (addr = (caddr_t)trunc_page((vm_offset_t) bp->b_data); 742 addr < bp->b_data + bp->b_bufsize; 743 addr += NBPG) 744 pmap_kremove((vm_offset_t) addr); 745 746 bp->b_data = bp->b_saveaddr; 747 bp->b_saveaddr = NULL; 748 749/* 750 * unhold the pde, and data pages 751 */ 752 for (addr = (caddr_t)trunc_page((vm_offset_t) bp->b_data); 753 addr < bp->b_data + bp->b_bufsize; 754 addr += NBPG) { 755 /* 756 * release the data page 757 */ 758 pa = pmap_kextract((vm_offset_t) addr); 759 vm_page_unhold(PHYS_TO_VM_PAGE(pa)); 760 } 761} 762 763/* 764 * Force reset the processor by invalidating the entire address space! 765 */ 766void 767cpu_reset() { 768 769 /* 770 * Attempt to do a CPU reset via the keyboard controller, 771 * do not turn of the GateA20, as any machine that fails 772 * to do the reset here would then end up in no man's land. 773 */ 774 775#ifndef BROKEN_KEYBOARD_RESET 776 outb(IO_KBD + 4, 0xFE); 777 DELAY(500000); /* wait 0.5 sec to see if that did it */ 778 printf("Keyboard reset did not work, attempting CPU shutdown\n"); 779 DELAY(1000000); /* wait 1 sec for printf to complete */ 780#endif 781 782 /* force a shutdown by unmapping entire address space ! */ 783 bzero((caddr_t) PTD, NBPG); 784 785 /* "good night, sweet prince .... <THUNK!>" */ 786 pmap_update(); 787 /* NOTREACHED */ 788 while(1); 789} 790 791/* 792 * Grow the user stack to allow for 'sp'. This version grows the stack in 793 * chunks of SGROWSIZ. 794 */ 795int 796grow(p, sp) 797 struct proc *p; 798 u_int sp; 799{ 800 unsigned int nss; 801 caddr_t v; 802 struct vmspace *vm = p->p_vmspace; 803 804 if ((caddr_t)sp <= vm->vm_maxsaddr || (unsigned)sp >= (unsigned)USRSTACK) 805 return (1); 806 807 nss = roundup(USRSTACK - (unsigned)sp, PAGE_SIZE); 808 809 if (nss > p->p_rlimit[RLIMIT_STACK].rlim_cur) 810 return (0); 811 812 if (vm->vm_ssize && roundup(vm->vm_ssize << PAGE_SHIFT, 813 SGROWSIZ) < nss) { 814 int grow_amount; 815 /* 816 * If necessary, grow the VM that the stack occupies 817 * to allow for the rlimit. This allows us to not have 818 * to allocate all of the VM up-front in execve (which 819 * is expensive). 820 * Grow the VM by the amount requested rounded up to 821 * the nearest SGROWSIZ to provide for some hysteresis. 822 */ 823 grow_amount = roundup((nss - (vm->vm_ssize << PAGE_SHIFT)), SGROWSIZ); 824 v = (char *)USRSTACK - roundup(vm->vm_ssize << PAGE_SHIFT, 825 SGROWSIZ) - grow_amount; 826 /* 827 * If there isn't enough room to extend by SGROWSIZ, then 828 * just extend to the maximum size 829 */ 830 if (v < vm->vm_maxsaddr) { 831 v = vm->vm_maxsaddr; 832 grow_amount = MAXSSIZ - (vm->vm_ssize << PAGE_SHIFT); 833 } 834 if ((grow_amount == 0) || (vm_map_find(&vm->vm_map, NULL, 0, (vm_offset_t *)&v, 835 grow_amount, FALSE, VM_PROT_ALL, VM_PROT_ALL, 0) != KERN_SUCCESS)) { 836 return (0); 837 } 838 vm->vm_ssize += grow_amount >> PAGE_SHIFT; 839 } 840 841 return (1); 842} 843 844/* 845 * prototype routine to implement the pre-zeroed page mechanism 846 * this routine is called from the idle loop. 847 */ 848int 849vm_page_zero_idle() { 850 vm_page_t m; 851 if ((cnt.v_free_count > cnt.v_interrupt_free_min) && 852 (m = vm_page_queue_free.tqh_first)) { 853 TAILQ_REMOVE(&vm_page_queue_free, m, pageq); 854 enable_intr(); 855 pmap_zero_page(VM_PAGE_TO_PHYS(m)); 856 disable_intr(); 857 TAILQ_INSERT_HEAD(&vm_page_queue_zero, m, pageq); 858 m->queue = PQ_ZERO; 859 ++vm_page_zero_count; 860 return 1; 861 } 862 return 0; 863} 864