vm_machdep.c revision 1889
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 1.22 1994/05/25 08:55:23 rgrimes Exp $ 42 */ 43 44#include "npx.h" 45#include <sys/param.h> 46#include <sys/systm.h> 47#include <sys/proc.h> 48#include <sys/malloc.h> 49#include <sys/buf.h> 50#include <sys/vnode.h> 51#include <sys/user.h> 52 53#include <machine/cpu.h> 54 55#include <vm/vm.h> 56#include <vm/vm_kern.h> 57 58#ifndef NOBOUNCE 59vm_map_t io_map; 60volatile int kvasfreecnt; 61 62 63caddr_t bouncememory; 64int bouncepages, bpwait; 65vm_offset_t *bouncepa; 66int bmwait, bmfreeing; 67 68#define BITS_IN_UNSIGNED (8*sizeof(unsigned)) 69int bounceallocarraysize; 70unsigned *bounceallocarray; 71int bouncefree; 72 73#define SIXTEENMEG (4096*4096) 74#define MAXBKVA 1024 75int maxbkva = MAXBKVA*NBPG; 76 77/* special list that can be used at interrupt time for eventual kva free */ 78struct kvasfree { 79 vm_offset_t addr; 80 vm_offset_t size; 81} kvaf[MAXBKVA]; 82 83 84vm_offset_t vm_bounce_kva(); 85/* 86 * get bounce buffer pages (count physically contiguous) 87 * (only 1 inplemented now) 88 */ 89vm_offset_t 90vm_bounce_page_find(count) 91 int count; 92{ 93 int bit; 94 int s,i; 95 96 if (count != 1) 97 panic("vm_bounce_page_find -- no support for > 1 page yet!!!"); 98 99 s = splbio(); 100retry: 101 for (i = 0; i < bounceallocarraysize; i++) { 102 if (bounceallocarray[i] != 0xffffffff) { 103 if (bit = ffs(~bounceallocarray[i])) { 104 bounceallocarray[i] |= 1 << (bit - 1) ; 105 bouncefree -= count; 106 splx(s); 107 return bouncepa[(i * BITS_IN_UNSIGNED + (bit - 1))]; 108 } 109 } 110 } 111 bpwait = 1; 112 tsleep((caddr_t) &bounceallocarray, PRIBIO, "bncwai", 0); 113 goto retry; 114} 115 116void 117vm_bounce_kva_free(addr, size, now) 118 vm_offset_t addr; 119 vm_offset_t size; 120 int now; 121{ 122 int s = splbio(); 123 kvaf[kvasfreecnt].addr = addr; 124 kvaf[kvasfreecnt].size = size; 125 ++kvasfreecnt; 126 if( now) { 127 /* 128 * this will do wakeups 129 */ 130 vm_bounce_kva(0,0); 131 } else { 132 if (bmwait) { 133 /* 134 * if anyone is waiting on the bounce-map, then wakeup 135 */ 136 wakeup((caddr_t) io_map); 137 bmwait = 0; 138 } 139 } 140 splx(s); 141} 142 143/* 144 * free count bounce buffer pages 145 */ 146void 147vm_bounce_page_free(pa, count) 148 vm_offset_t pa; 149 int count; 150{ 151 int allocindex; 152 int index; 153 int bit; 154 155 if (count != 1) 156 panic("vm_bounce_page_free -- no support for > 1 page yet!!!\n"); 157 158 for(index=0;index<bouncepages;index++) { 159 if( pa == bouncepa[index]) 160 break; 161 } 162 163 if( index == bouncepages) 164 panic("vm_bounce_page_free: invalid bounce buffer"); 165 166 allocindex = index / BITS_IN_UNSIGNED; 167 bit = index % BITS_IN_UNSIGNED; 168 169 bounceallocarray[allocindex] &= ~(1 << bit); 170 171 bouncefree += count; 172 if (bpwait) { 173 bpwait = 0; 174 wakeup((caddr_t) &bounceallocarray); 175 } 176} 177 178/* 179 * allocate count bounce buffer kva pages 180 */ 181vm_offset_t 182vm_bounce_kva(size, waitok) 183 int size; 184 int waitok; 185{ 186 int i; 187 int startfree; 188 vm_offset_t kva = 0; 189 int s = splbio(); 190more: 191 if (!bmfreeing && kvasfreecnt) { 192 bmfreeing = 1; 193 for (i = 0; i < kvasfreecnt; i++) { 194 pmap_remove(kernel_pmap, 195 kvaf[i].addr, kvaf[i].addr + kvaf[i].size); 196 kmem_free_wakeup(io_map, kvaf[i].addr, 197 kvaf[i].size); 198 } 199 kvasfreecnt = 0; 200 bmfreeing = 0; 201 if( bmwait) { 202 bmwait = 0; 203 wakeup( (caddr_t) io_map); 204 } 205 } 206 207 if( size == 0) { 208 splx(s); 209 return NULL; 210 } 211 212 if ((kva = kmem_alloc_pageable(io_map, size)) == 0) { 213 if( !waitok) { 214 splx(s); 215 return NULL; 216 } 217 bmwait = 1; 218 tsleep((caddr_t) io_map, PRIBIO, "bmwait", 0); 219 goto more; 220 } 221 splx(s); 222 return kva; 223} 224 225/* 226 * same as vm_bounce_kva -- but really allocate (but takes pages as arg) 227 */ 228vm_offset_t 229vm_bounce_kva_alloc(count) 230int count; 231{ 232 int i; 233 vm_offset_t kva; 234 vm_offset_t pa; 235 if( bouncepages == 0) { 236 kva = (vm_offset_t) malloc(count*NBPG, M_TEMP, M_WAITOK); 237 return kva; 238 } 239 kva = vm_bounce_kva(count*NBPG, 1); 240 for(i=0;i<count;i++) { 241 pa = vm_bounce_page_find(1); 242 pmap_kenter(kva + i * NBPG, pa); 243 } 244 pmap_update(); 245 return kva; 246} 247 248/* 249 * same as vm_bounce_kva_free -- but really free 250 */ 251void 252vm_bounce_kva_alloc_free(kva, count) 253 vm_offset_t kva; 254 int count; 255{ 256 int i; 257 vm_offset_t pa; 258 if( bouncepages == 0) { 259 free((caddr_t) kva, M_TEMP); 260 return; 261 } 262 for(i = 0; i < count; i++) { 263 pa = pmap_kextract(kva + i * NBPG); 264 vm_bounce_page_free(pa, 1); 265 } 266 vm_bounce_kva_free(kva, count*NBPG, 0); 267} 268 269/* 270 * do the things necessary to the struct buf to implement 271 * bounce buffers... inserted before the disk sort 272 */ 273void 274vm_bounce_alloc(bp) 275 struct buf *bp; 276{ 277 int countvmpg; 278 vm_offset_t vastart, vaend; 279 vm_offset_t vapstart, vapend; 280 vm_offset_t va, kva; 281 vm_offset_t pa; 282 int dobounceflag = 0; 283 int bounceindex; 284 int i; 285 int s; 286 287 if (bouncepages == 0) 288 return; 289 290 if (bp->b_flags & B_BOUNCE) { 291 printf("vm_bounce_alloc: called recursively???\n"); 292 return; 293 } 294 295 if (bp->b_bufsize < bp->b_bcount) { 296 printf("vm_bounce_alloc: b_bufsize(0x%x) < b_bcount(0x%x) !!!!\n", 297 bp->b_bufsize, bp->b_bcount); 298 panic("vm_bounce_alloc"); 299 } 300 301/* 302 * This is not really necessary 303 * if( bp->b_bufsize != bp->b_bcount) { 304 * printf("size: %d, count: %d\n", bp->b_bufsize, bp->b_bcount); 305 * } 306 */ 307 308 309 vastart = (vm_offset_t) bp->b_data; 310 vaend = (vm_offset_t) bp->b_data + bp->b_bufsize; 311 312 vapstart = i386_trunc_page(vastart); 313 vapend = i386_round_page(vaend); 314 countvmpg = (vapend - vapstart) / NBPG; 315 316/* 317 * if any page is above 16MB, then go into bounce-buffer mode 318 */ 319 va = vapstart; 320 for (i = 0; i < countvmpg; i++) { 321 pa = pmap_kextract(va); 322 if (pa >= SIXTEENMEG) 323 ++dobounceflag; 324 va += NBPG; 325 } 326 if (dobounceflag == 0) 327 return; 328 329 if (bouncepages < dobounceflag) 330 panic("Not enough bounce buffers!!!"); 331 332/* 333 * allocate a replacement kva for b_addr 334 */ 335 kva = vm_bounce_kva(countvmpg*NBPG, 1); 336#if 0 337 printf("%s: vapstart: %x, vapend: %x, countvmpg: %d, kva: %x ", 338 (bp->b_flags & B_READ) ? "read":"write", 339 vapstart, vapend, countvmpg, kva); 340#endif 341 va = vapstart; 342 for (i = 0; i < countvmpg; i++) { 343 pa = pmap_kextract(va); 344 if (pa >= SIXTEENMEG) { 345 /* 346 * allocate a replacement page 347 */ 348 vm_offset_t bpa = vm_bounce_page_find(1); 349 pmap_kenter(kva + (NBPG * i), bpa); 350#if 0 351 printf("r(%d): (%x,%x,%x) ", i, va, pa, bpa); 352#endif 353 /* 354 * if we are writing, the copy the data into the page 355 */ 356 if ((bp->b_flags & B_READ) == 0) { 357 pmap_update(); 358 bcopy((caddr_t) va, (caddr_t) kva + (NBPG * i), NBPG); 359 } 360 } else { 361 /* 362 * use original page 363 */ 364 pmap_kenter(kva + (NBPG * i), pa); 365 } 366 va += NBPG; 367 } 368 pmap_update(); 369 370/* 371 * flag the buffer as being bounced 372 */ 373 bp->b_flags |= B_BOUNCE; 374/* 375 * save the original buffer kva 376 */ 377 bp->b_savekva = bp->b_data; 378/* 379 * put our new kva into the buffer (offset by original offset) 380 */ 381 bp->b_data = (caddr_t) (((vm_offset_t) kva) | 382 ((vm_offset_t) bp->b_savekva & (NBPG - 1))); 383#if 0 384 printf("b_savekva: %x, newva: %x\n", bp->b_savekva, bp->b_data); 385#endif 386 return; 387} 388 389/* 390 * hook into biodone to free bounce buffer 391 */ 392void 393vm_bounce_free(bp) 394 struct buf *bp; 395{ 396 int i; 397 vm_offset_t origkva, bouncekva, bouncekvaend; 398 int countvmpg; 399 int s; 400 401/* 402 * if this isn't a bounced buffer, then just return 403 */ 404 if ((bp->b_flags & B_BOUNCE) == 0) 405 return; 406 407/* 408 * This check is not necessary 409 * if (bp->b_bufsize != bp->b_bcount) { 410 * printf("vm_bounce_free: b_bufsize=%d, b_bcount=%d\n", 411 * bp->b_bufsize, bp->b_bcount); 412 * } 413 */ 414 415 origkva = (vm_offset_t) bp->b_savekva; 416 bouncekva = (vm_offset_t) bp->b_data; 417/* 418 printf("free: %d ", bp->b_bufsize); 419*/ 420 421/* 422 * check every page in the kva space for b_addr 423 */ 424 for (i = 0; i < bp->b_bufsize; ) { 425 vm_offset_t mybouncepa; 426 vm_offset_t copycount; 427 428 copycount = i386_round_page(bouncekva + 1) - bouncekva; 429 mybouncepa = pmap_kextract(i386_trunc_page(bouncekva)); 430 431/* 432 * if this is a bounced pa, then process as one 433 */ 434 if ( mybouncepa != pmap_kextract( i386_trunc_page( origkva))) { 435 vm_offset_t tocopy = copycount; 436 if (i + tocopy > bp->b_bufsize) 437 tocopy = bp->b_bufsize - i; 438/* 439 * if this is a read, then copy from bounce buffer into original buffer 440 */ 441 if (bp->b_flags & B_READ) 442 bcopy((caddr_t) bouncekva, (caddr_t) origkva, tocopy); 443/* 444 * free the bounce allocation 445 */ 446 447/* 448 printf("(kva: %x, pa: %x)", bouncekva, mybouncepa); 449*/ 450 vm_bounce_page_free(mybouncepa, 1); 451 } 452 453 origkva += copycount; 454 bouncekva += copycount; 455 i += copycount; 456 } 457 458/* 459 printf("\n"); 460*/ 461/* 462 * add the old kva into the "to free" list 463 */ 464 465 bouncekva= i386_trunc_page((vm_offset_t) bp->b_data); 466 bouncekvaend= i386_round_page((vm_offset_t)bp->b_data + bp->b_bufsize); 467 468/* 469 printf("freeva: %d\n", (bouncekvaend - bouncekva) / NBPG); 470*/ 471 vm_bounce_kva_free( bouncekva, (bouncekvaend - bouncekva), 0); 472 bp->b_data = bp->b_savekva; 473 bp->b_savekva = 0; 474 bp->b_flags &= ~B_BOUNCE; 475 476 return; 477} 478 479 480/* 481 * init the bounce buffer system 482 */ 483void 484vm_bounce_init() 485{ 486 vm_offset_t minaddr, maxaddr; 487 int i; 488 489 kvasfreecnt = 0; 490 491 if (bouncepages == 0) 492 return; 493 494 bounceallocarraysize = (bouncepages + BITS_IN_UNSIGNED - 1) / BITS_IN_UNSIGNED; 495 bounceallocarray = malloc(bounceallocarraysize * sizeof(unsigned), M_TEMP, M_NOWAIT); 496 497 if (!bounceallocarray) 498 panic("Cannot allocate bounce resource array\n"); 499 500 bzero(bounceallocarray, bounceallocarraysize * sizeof(unsigned)); 501 bouncepa = malloc(bouncepages * sizeof(vm_offset_t), M_TEMP, M_NOWAIT); 502 if (!bouncepa) 503 panic("Cannot allocate physical memory array\n"); 504 505 for(i=0;i<bouncepages;i++) { 506 vm_offset_t pa; 507 if( (pa = pmap_kextract((vm_offset_t) bouncememory + i * NBPG)) >= SIXTEENMEG) 508 panic("bounce memory out of range"); 509 if( pa == 0) 510 panic("bounce memory not resident"); 511 bouncepa[i] = pa; 512 } 513 bouncefree = bouncepages; 514 515} 516#endif /* NOBOUNCE */ 517/* 518 * quick version of vm_fault 519 */ 520 521void 522vm_fault_quick( v, prot) 523 vm_offset_t v; 524 int prot; 525{ 526 if( (cpu_class == CPUCLASS_386) && 527 (prot & VM_PROT_WRITE)) 528 vm_fault(&curproc->p_vmspace->vm_map, v, 529 VM_PROT_READ|VM_PROT_WRITE, FALSE); 530 else if( prot & VM_PROT_WRITE) 531 *(volatile char *)v += 0; 532 else 533 *(volatile char *)v; 534} 535 536 537/* 538 * Finish a fork operation, with process p2 nearly set up. 539 * Copy and update the kernel stack and pcb, making the child 540 * ready to run, and marking it so that it can return differently 541 * than the parent. Returns 1 in the child process, 0 in the parent. 542 * We currently double-map the user area so that the stack is at the same 543 * address in each process; in the future we will probably relocate 544 * the frame pointers on the stack after copying. 545 */ 546int 547cpu_fork(p1, p2) 548 register struct proc *p1, *p2; 549{ 550 register struct user *up = p2->p_addr; 551 int foo, offset, addr, i; 552 extern char kstack[]; 553 extern int mvesp(); 554 555 /* 556 * Copy pcb and stack from proc p1 to p2. 557 * We do this as cheaply as possible, copying only the active 558 * part of the stack. The stack and pcb need to agree; 559 * this is tricky, as the final pcb is constructed by savectx, 560 * but its frame isn't yet on the stack when the stack is copied. 561 * swtch compensates for this when the child eventually runs. 562 * This should be done differently, with a single call 563 * that copies and updates the pcb+stack, 564 * replacing the bcopy and savectx. 565 */ 566 p2->p_addr->u_pcb = p1->p_addr->u_pcb; 567 offset = mvesp() - (int)kstack; 568 bcopy((caddr_t)kstack + offset, (caddr_t)p2->p_addr + offset, 569 (unsigned) ctob(UPAGES) - offset); 570 p2->p_md.md_regs = p1->p_md.md_regs; 571 572 pmap_activate(&p2->p_vmspace->vm_pmap, &up->u_pcb); 573 574 /* 575 * 576 * Arrange for a non-local goto when the new process 577 * is started, to resume here, returning nonzero from setjmp. 578 */ 579 if (savectx(up, 1)) { 580 /* 581 * Return 1 in child. 582 */ 583 return (1); 584 } 585 return (0); 586} 587 588void 589cpu_exit(p) 590 register struct proc *p; 591{ 592 593#if NNPX > 0 594 npxexit(p); 595#endif /* NNPX */ 596 curproc = p; 597 mi_switch(); 598 /* 599 * This is to shutup the compiler, and if swtch() failed I suppose 600 * this would be a good thing. This keeps gcc happy because panic 601 * is a volatile void function as well. 602 */ 603 panic("cpu_exit"); 604} 605 606void 607cpu_wait(p) struct proc *p; { 608/* extern vm_map_t upages_map; */ 609 extern char kstack[]; 610 611 /* drop per-process resources */ 612 pmap_remove(vm_map_pmap(kernel_map), (vm_offset_t) p->p_addr, 613 ((vm_offset_t) p->p_addr) + ctob(UPAGES)); 614 kmem_free(kernel_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/* 634 * Set a red zone in the kernel stack after the u. area. 635 */ 636void 637setredzone(pte, vaddr) 638 u_short *pte; 639 caddr_t vaddr; 640{ 641/* eventually do this by setting up an expand-down stack segment 642 for ss0: selector, allowing stack access down to top of u. 643 this means though that protection violations need to be handled 644 thru a double fault exception that must do an integral task 645 switch to a known good context, within which a dump can be 646 taken. a sensible scheme might be to save the initial context 647 used by sched (that has physical memory mapped 1:1 at bottom) 648 and take the dump while still in mapped mode */ 649} 650 651/* 652 * Move pages from one kernel virtual address to another. 653 * Both addresses are assumed to reside in the Sysmap, 654 * and size must be a multiple of CLSIZE. 655 */ 656 657void 658pagemove(from, to, size) 659 register caddr_t from, to; 660 int size; 661{ 662 register vm_offset_t pa; 663 664 if (size & CLOFSET) 665 panic("pagemove"); 666 while (size > 0) { 667 pa = pmap_kextract((vm_offset_t)from); 668 if (pa == 0) 669 panic("pagemove 2"); 670 if (pmap_kextract((vm_offset_t)to) != 0) 671 panic("pagemove 3"); 672 pmap_remove(kernel_pmap, 673 (vm_offset_t)from, (vm_offset_t)from + PAGE_SIZE); 674 pmap_kenter( (vm_offset_t)to, pa); 675 from += PAGE_SIZE; 676 to += PAGE_SIZE; 677 size -= PAGE_SIZE; 678 } 679 pmap_update(); 680} 681 682/* 683 * Convert kernel VA to physical address 684 */ 685u_long 686kvtop(void *addr) 687{ 688 vm_offset_t va; 689 690 va = pmap_kextract((vm_offset_t)addr); 691 if (va == 0) 692 panic("kvtop: zero page frame"); 693 return((int)va); 694} 695 696/* 697 * Map an IO request into kernel virtual address space. 698 * 699 * All requests are (re)mapped into kernel VA space. 700 * Notice that we use b_bufsize for the size of the buffer 701 * to be mapped. b_bcount might be modified by the driver. 702 */ 703void 704vmapbuf(bp) 705 register struct buf *bp; 706{ 707 register int npf; 708 register caddr_t addr; 709 int off; 710 vm_offset_t kva; 711 vm_offset_t pa, lastv, v; 712 713 if ((bp->b_flags & B_PHYS) == 0) 714 panic("vmapbuf"); 715 716 /* 717 * this is the kva that is to be used for 718 * the temporary kernel mapping 719 */ 720 kva = (vm_offset_t) bp->b_saveaddr; 721 722 lastv = 0; 723 for (addr = (caddr_t)trunc_page(bp->b_data); 724 addr < bp->b_data + bp->b_bufsize; 725 addr += PAGE_SIZE) { 726 727/* 728 * make sure that the pde is valid and held 729 */ 730 v = trunc_page(((vm_offset_t)vtopte(addr))); 731 if (v != lastv) { 732 vm_fault_quick(v, VM_PROT_READ); 733 pa = pmap_extract(&curproc->p_vmspace->vm_pmap, v); 734 vm_page_hold(PHYS_TO_VM_PAGE(pa)); 735 lastv = v; 736 } 737 738/* 739 * do the vm_fault if needed, do the copy-on-write thing when 740 * reading stuff off device into memory. 741 */ 742 vm_fault_quick(addr, 743 (bp->b_flags&B_READ)?(VM_PROT_READ|VM_PROT_WRITE):VM_PROT_READ); 744 pa = pmap_extract(&curproc->p_vmspace->vm_pmap, (vm_offset_t) addr); 745/* 746 * hold the data page 747 */ 748 vm_page_hold(PHYS_TO_VM_PAGE(pa)); 749 } 750 751 addr = bp->b_saveaddr = bp->b_data; 752 off = (int)addr & PGOFSET; 753 npf = btoc(round_page(bp->b_bufsize + off)); 754 bp->b_data = (caddr_t) (kva + off); 755 while (npf--) { 756 pa = pmap_extract(&curproc->p_vmspace->vm_pmap, (vm_offset_t)addr); 757 if (pa == 0) 758 panic("vmapbuf: null page frame"); 759 pmap_kenter(kva, trunc_page(pa)); 760 addr += PAGE_SIZE; 761 kva += PAGE_SIZE; 762 } 763 pmap_update(); 764} 765 766/* 767 * Free the io map PTEs associated with this IO operation. 768 * We also invalidate the TLB entries and restore the original b_addr. 769 */ 770void 771vunmapbuf(bp) 772 register struct buf *bp; 773{ 774 register int npf; 775 register caddr_t addr = bp->b_data; 776 vm_offset_t kva,va,v,lastv,pa; 777 778 if ((bp->b_flags & B_PHYS) == 0) 779 panic("vunmapbuf"); 780 bp->b_data = bp->b_saveaddr; 781 bp->b_saveaddr = NULL; 782 783/* 784 * unhold the pde, and data pages 785 */ 786 lastv = 0; 787 for (addr = (caddr_t)trunc_page(bp->b_data); 788 addr < bp->b_data + bp->b_bufsize; 789 addr += NBPG) { 790 791 /* 792 * release the data page 793 */ 794 pa = pmap_extract(&curproc->p_vmspace->vm_pmap, (vm_offset_t) addr); 795 vm_page_unhold(PHYS_TO_VM_PAGE(pa)); 796 797 /* 798 * and unhold the page table 799 */ 800 v = trunc_page(((vm_offset_t)vtopte(addr))); 801 if (v != lastv) { 802 pa = pmap_extract(&curproc->p_vmspace->vm_pmap, v); 803 vm_page_unhold(PHYS_TO_VM_PAGE(pa)); 804 lastv = v; 805 } 806 pmap_kremove( addr); 807 } 808} 809 810/* 811 * Force reset the processor by invalidating the entire address space! 812 */ 813void 814cpu_reset() { 815 816 /* force a shutdown by unmapping entire address space ! */ 817 bzero((caddr_t) PTD, NBPG); 818 819 /* "good night, sweet prince .... <THUNK!>" */ 820 tlbflush(); 821 /* NOTREACHED */ 822 while(1); 823} 824 825/* 826 * Grow the user stack to allow for 'sp'. This version grows the stack in 827 * chunks of SGROWSIZ. 828 */ 829int 830grow(p, sp) 831 struct proc *p; 832 u_int sp; 833{ 834 unsigned int nss; 835 caddr_t v; 836 struct vmspace *vm = p->p_vmspace; 837 838 if ((caddr_t)sp <= vm->vm_maxsaddr || (unsigned)sp >= (unsigned)USRSTACK) 839 return (1); 840 841 nss = roundup(USRSTACK - (unsigned)sp, PAGE_SIZE); 842 843 if (nss > p->p_rlimit[RLIMIT_STACK].rlim_cur) 844 return (0); 845 846 if (vm->vm_ssize && roundup(vm->vm_ssize << PAGE_SHIFT, 847 SGROWSIZ) < nss) { 848 int grow_amount; 849 /* 850 * If necessary, grow the VM that the stack occupies 851 * to allow for the rlimit. This allows us to not have 852 * to allocate all of the VM up-front in execve (which 853 * is expensive). 854 * Grow the VM by the amount requested rounded up to 855 * the nearest SGROWSIZ to provide for some hysteresis. 856 */ 857 grow_amount = roundup((nss - (vm->vm_ssize << PAGE_SHIFT)), SGROWSIZ); 858 v = (char *)USRSTACK - roundup(vm->vm_ssize << PAGE_SHIFT, 859 SGROWSIZ) - grow_amount; 860 /* 861 * If there isn't enough room to extend by SGROWSIZ, then 862 * just extend to the maximum size 863 */ 864 if (v < vm->vm_maxsaddr) { 865 v = vm->vm_maxsaddr; 866 grow_amount = MAXSSIZ - (vm->vm_ssize << PAGE_SHIFT); 867 } 868 if (vm_allocate(&vm->vm_map, (vm_offset_t *)&v, 869 grow_amount, FALSE) != KERN_SUCCESS) { 870 return (0); 871 } 872 vm->vm_ssize += grow_amount >> PAGE_SHIFT; 873 } 874 875 return (1); 876} 877