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 1.42 1995/09/03 20:39:22 dyson 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/clock.h> 54 #include <machine/cpu.h> 55 #include <machine/md_var.h> 56 57 #include <vm/vm.h> 58 #include <vm/vm_kern.h> 59 #include <vm/vm_page.h> 60 61 #include <i386/isa/isa.h> 62 63 #ifdef BOUNCE_BUFFERS 64 volatile int kvasfreecnt; 65 66 caddr_t bouncememory; 67 int bouncepages, bpwait; 68 vm_offset_t *bouncepa; 69 int bmwait, bmfreeing; 70 71 #define BITS_IN_UNSIGNED (8*sizeof(unsigned)) 72 int bounceallocarraysize; 73 unsigned *bounceallocarray; 74 int bouncefree; 75 76 #define SIXTEENMEG (4096*4096) 77 #define MAXBKVA 1024 78 int maxbkva = MAXBKVA*NBPG; 79 80 /* special list that can be used at interrupt time for eventual kva free */ 81 struct kvasfree { 82 vm_offset_t addr; 83 vm_offset_t size; 84 } kvaf[MAXBKVA]; 85 86 87 vm_offset_t vm_bounce_kva(); 88 /* 89 * get bounce buffer pages (count physically contiguous) 90 * (only 1 inplemented now) 91 */ 92 vm_offset_t 93 vm_bounce_page_find(count) 94 int count; 95 { 96 int bit; 97 int s,i; 98 99 if (count != 1) 100 panic("vm_bounce_page_find -- no support for > 1 page yet!!!"); 101 102 s = splbio(); 103 retry: 104 for (i = 0; i < bounceallocarraysize; i++) { 105 if (bounceallocarray[i] != 0xffffffff) { 106 bit = ffs(~bounceallocarray[i]); 107 if (bit) { 108 bounceallocarray[i] |= 1 << (bit - 1) ; 109 bouncefree -= count; 110 splx(s); 111 return bouncepa[(i * BITS_IN_UNSIGNED + (bit - 1))]; 112 } 113 } 114 } 115 bpwait = 1; 116 tsleep((caddr_t) &bounceallocarray, PRIBIO, "bncwai", 0); 117 goto retry; 118 } 119 120 void 121 vm_bounce_kva_free(addr, size, now) 122 vm_offset_t addr; 123 vm_offset_t size; 124 int now; 125 { 126 int s = splbio(); 127 kvaf[kvasfreecnt].addr = addr; 128 kvaf[kvasfreecnt].size = size; 129 ++kvasfreecnt; 130 if( now) { 131 /* 132 * this will do wakeups 133 */ 134 vm_bounce_kva(0,0); 135 } else { 136 if (bmwait) { 137 /* 138 * if anyone is waiting on the bounce-map, then wakeup 139 */ 140 wakeup((caddr_t) io_map); 141 bmwait = 0; 142 } 143 } 144 splx(s); 145 } 146 147 /* 148 * free count bounce buffer pages 149 */ 150 void 151 vm_bounce_page_free(pa, count) 152 vm_offset_t pa; 153 int count; 154 { 155 int allocindex; 156 int index; 157 int bit; 158 159 if (count != 1) 160 panic("vm_bounce_page_free -- no support for > 1 page yet!!!"); 161 162 for(index=0;index<bouncepages;index++) { 163 if( pa == bouncepa[index]) 164 break; 165 } 166 167 if( index == bouncepages) 168 panic("vm_bounce_page_free: invalid bounce buffer"); 169 170 allocindex = index / BITS_IN_UNSIGNED; 171 bit = index % BITS_IN_UNSIGNED; 172 173 bounceallocarray[allocindex] &= ~(1 << bit); 174 175 bouncefree += count; 176 if (bpwait) { 177 bpwait = 0; 178 wakeup((caddr_t) &bounceallocarray); 179 } 180 } 181 182 /* 183 * allocate count bounce buffer kva pages 184 */ 185 vm_offset_t 186 vm_bounce_kva(size, waitok) 187 int size; 188 int waitok; 189 { 190 int i; 191 vm_offset_t kva = 0; 192 vm_offset_t off; 193 int s = splbio(); 194 more: 195 if (!bmfreeing && kvasfreecnt) { 196 bmfreeing = 1; 197 for (i = 0; i < kvasfreecnt; i++) { 198 for(off=0;off<kvaf[i].size;off+=NBPG) { 199 pmap_kremove( kvaf[i].addr + off); 200 } 201 kmem_free_wakeup(io_map, kvaf[i].addr, 202 kvaf[i].size); 203 } 204 kvasfreecnt = 0; 205 bmfreeing = 0; 206 if( bmwait) { 207 bmwait = 0; 208 wakeup( (caddr_t) io_map); 209 } 210 } 211 212 if( size == 0) { 213 splx(s); 214 return NULL; 215 } 216 217 if ((kva = kmem_alloc_pageable(io_map, size)) == 0) { 218 if( !waitok) { 219 splx(s); 220 return NULL; 221 } 222 bmwait = 1; 223 tsleep((caddr_t) io_map, PRIBIO, "bmwait", 0); 224 goto more; 225 } 226 splx(s); 227 return kva; 228 } 229 230 /* 231 * same as vm_bounce_kva -- but really allocate (but takes pages as arg) 232 */ 233 vm_offset_t 234 vm_bounce_kva_alloc(count) 235 int count; 236 { 237 int i; 238 vm_offset_t kva; 239 vm_offset_t pa; 240 if( bouncepages == 0) { 241 kva = (vm_offset_t) malloc(count*NBPG, M_TEMP, M_WAITOK); 242 return kva; 243 } 244 kva = vm_bounce_kva(count*NBPG, 1); 245 for(i=0;i<count;i++) { 246 pa = vm_bounce_page_find(1); 247 pmap_kenter(kva + i * NBPG, pa); 248 } 249 return kva; 250 } 251 252 /* 253 * same as vm_bounce_kva_free -- but really free 254 */ 255 void 256 vm_bounce_kva_alloc_free(kva, count) 257 vm_offset_t kva; 258 int count; 259 { 260 int i; 261 vm_offset_t pa; 262 if( bouncepages == 0) { 263 free((caddr_t) kva, M_TEMP); 264 return; 265 } 266 for(i = 0; i < count; i++) { 267 pa = pmap_kextract(kva + i * NBPG); 268 vm_bounce_page_free(pa, 1); 269 } 270 vm_bounce_kva_free(kva, count*NBPG, 0); 271 } 272 273 /* 274 * do the things necessary to the struct buf to implement 275 * bounce buffers... inserted before the disk sort 276 */ 277 void 278 vm_bounce_alloc(bp) 279 struct buf *bp; 280 { 281 int countvmpg; 282 vm_offset_t vastart, vaend; 283 vm_offset_t vapstart, vapend; 284 vm_offset_t va, kva; 285 vm_offset_t pa; 286 int dobounceflag = 0; 287 int i; 288 289 if (bouncepages == 0) 290 return; 291 292 if (bp->b_flags & B_BOUNCE) { 293 printf("vm_bounce_alloc: called recursively???\n"); 294 return; 295 } 296 297 if (bp->b_bufsize < bp->b_bcount) { 298 printf( 299 "vm_bounce_alloc: b_bufsize(0x%lx) < b_bcount(0x%lx) !!\n", 300 bp->b_bufsize, bp->b_bcount); 301 panic("vm_bounce_alloc"); 302 } 303 304 /* 305 * This is not really necessary 306 * if( bp->b_bufsize != bp->b_bcount) { 307 * printf("size: %d, count: %d\n", bp->b_bufsize, bp->b_bcount); 308 * } 309 */ 310 311 312 vastart = (vm_offset_t) bp->b_data; 313 vaend = (vm_offset_t) bp->b_data + bp->b_bufsize; 314 315 vapstart = i386_trunc_page(vastart); 316 vapend = i386_round_page(vaend); 317 countvmpg = (vapend - vapstart) / NBPG; 318 319 /* 320 * if any page is above 16MB, then go into bounce-buffer mode 321 */ 322 va = vapstart; 323 for (i = 0; i < countvmpg; i++) { 324 pa = pmap_kextract(va); 325 if (pa >= SIXTEENMEG) 326 ++dobounceflag; 327 if( pa == 0) 328 panic("vm_bounce_alloc: Unmapped page"); 329 va += NBPG; 330 } 331 if (dobounceflag == 0) 332 return; 333 334 if (bouncepages < dobounceflag) 335 panic("Not enough bounce buffers!!!"); 336 337 /* 338 * allocate a replacement kva for b_addr 339 */ 340 kva = vm_bounce_kva(countvmpg*NBPG, 1); 341 #if 0 342 printf("%s: vapstart: %x, vapend: %x, countvmpg: %d, kva: %x ", 343 (bp->b_flags & B_READ) ? "read":"write", 344 vapstart, vapend, countvmpg, kva); 345 #endif 346 va = vapstart; 347 for (i = 0; i < countvmpg; i++) { 348 pa = pmap_kextract(va); 349 if (pa >= SIXTEENMEG) { 350 /* 351 * allocate a replacement page 352 */ 353 vm_offset_t bpa = vm_bounce_page_find(1); 354 pmap_kenter(kva + (NBPG * i), bpa); 355 #if 0 356 printf("r(%d): (%x,%x,%x) ", i, va, pa, bpa); 357 #endif 358 /* 359 * if we are writing, the copy the data into the page 360 */ 361 if ((bp->b_flags & B_READ) == 0) { 362 bcopy((caddr_t) va, (caddr_t) kva + (NBPG * i), NBPG); 363 } 364 } else { 365 /* 366 * use original page 367 */ 368 pmap_kenter(kva + (NBPG * i), pa); 369 } 370 va += NBPG; 371 } 372 373 /* 374 * flag the buffer as being bounced 375 */ 376 bp->b_flags |= B_BOUNCE; 377 /* 378 * save the original buffer kva 379 */ 380 bp->b_savekva = bp->b_data; 381 /* 382 * put our new kva into the buffer (offset by original offset) 383 */ 384 bp->b_data = (caddr_t) (((vm_offset_t) kva) | 385 ((vm_offset_t) bp->b_savekva & (NBPG - 1))); 386 #if 0 387 printf("b_savekva: %x, newva: %x\n", bp->b_savekva, bp->b_data); 388 #endif 389 return; 390 } 391 392 /* 393 * hook into biodone to free bounce buffer 394 */ 395 void 396 vm_bounce_free(bp) 397 struct buf *bp; 398 { 399 int i; 400 vm_offset_t origkva, bouncekva, bouncekvaend; 401 402 /* 403 * if this isn't a bounced buffer, then just return 404 */ 405 if ((bp->b_flags & B_BOUNCE) == 0) 406 return; 407 408 /* 409 * This check is not necessary 410 * if (bp->b_bufsize != bp->b_bcount) { 411 * printf("vm_bounce_free: b_bufsize=%d, b_bcount=%d\n", 412 * bp->b_bufsize, bp->b_bcount); 413 * } 414 */ 415 416 origkva = (vm_offset_t) bp->b_savekva; 417 bouncekva = (vm_offset_t) bp->b_data; 418 /* 419 printf("free: %d ", bp->b_bufsize); 420 */ 421 422 /* 423 * check every page in the kva space for b_addr 424 */ 425 for (i = 0; i < bp->b_bufsize; ) { 426 vm_offset_t mybouncepa; 427 vm_offset_t copycount; 428 429 copycount = i386_round_page(bouncekva + 1) - bouncekva; 430 mybouncepa = pmap_kextract(i386_trunc_page(bouncekva)); 431 432 /* 433 * if this is a bounced pa, then process as one 434 */ 435 if ( mybouncepa != pmap_kextract( i386_trunc_page( origkva))) { 436 vm_offset_t tocopy = copycount; 437 if (i + tocopy > bp->b_bufsize) 438 tocopy = bp->b_bufsize - i; 439 /* 440 * if this is a read, then copy from bounce buffer into original buffer 441 */ 442 if (bp->b_flags & B_READ) 443 bcopy((caddr_t) bouncekva, (caddr_t) origkva, tocopy); 444 /* 445 * free the bounce allocation 446 */ 447 448 /* 449 printf("(kva: %x, pa: %x)", bouncekva, mybouncepa); 450 */ 451 vm_bounce_page_free(mybouncepa, 1); 452 } 453 454 origkva += copycount; 455 bouncekva += copycount; 456 i += copycount; 457 } 458 459 /* 460 printf("\n"); 461 */ 462 /* 463 * add the old kva into the "to free" list 464 */ 465 466 bouncekva= i386_trunc_page((vm_offset_t) bp->b_data); 467 bouncekvaend= i386_round_page((vm_offset_t)bp->b_data + bp->b_bufsize); 468 469 /* 470 printf("freeva: %d\n", (bouncekvaend - bouncekva) / NBPG); 471 */ 472 vm_bounce_kva_free( bouncekva, (bouncekvaend - bouncekva), 0); 473 bp->b_data = bp->b_savekva; 474 bp->b_savekva = 0; 475 bp->b_flags &= ~B_BOUNCE; 476 477 return; 478 } 479 480 481 /* 482 * init the bounce buffer system 483 */ 484 void 485 vm_bounce_init() 486 { 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"); 499 500 bouncepa = malloc(bouncepages * sizeof(vm_offset_t), M_TEMP, M_NOWAIT); 501 if (!bouncepa) 502 panic("Cannot allocate physical memory array"); 503 504 for(i=0;i<bounceallocarraysize;i++) { 505 bounceallocarray[i] = 0xffffffff; 506 } 507 508 for(i=0;i<bouncepages;i++) { 509 vm_offset_t pa; 510 if( (pa = pmap_kextract((vm_offset_t) bouncememory + i * NBPG)) >= SIXTEENMEG) 511 panic("bounce memory out of range"); 512 if( pa == 0) 513 panic("bounce memory not resident"); 514 bouncepa[i] = pa; 515 bounceallocarray[i/(8*sizeof(int))] &= ~(1<<(i%(8*sizeof(int)))); 516 } 517 bouncefree = bouncepages; 518 519 } 520 #endif /* BOUNCE_BUFFERS */ 521 /* 522 * quick version of vm_fault 523 */ 524 525 void 526 vm_fault_quick( v, prot) 527 vm_offset_t v; 528 int prot; 529 { 530 if (prot & VM_PROT_WRITE) 531 subyte((char *)v, fubyte((char *)v)); 532 else 533 (void) fubyte((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 */ 546 int 547 cpu_fork(p1, p2) 548 register struct proc *p1, *p2; 549 { 550 register struct user *up = p2->p_addr; 551 int offset; 552 553 /* 554 * Copy pcb and stack from proc p1 to p2. 555 * We do this as cheaply as possible, copying only the active 556 * part of the stack. The stack and pcb need to agree; 557 * this is tricky, as the final pcb is constructed by savectx, 558 * but its frame isn't yet on the stack when the stack is copied. 559 * swtch compensates for this when the child eventually runs. 560 * This should be done differently, with a single call 561 * that copies and updates the pcb+stack, 562 * replacing the bcopy and savectx. 563 */ 564 p2->p_addr->u_pcb = p1->p_addr->u_pcb; 565 offset = mvesp() - (int)kstack; 566 bcopy((caddr_t)kstack + offset, (caddr_t)p2->p_addr + offset, 567 (unsigned) ctob(UPAGES) - offset); 568 p2->p_md.md_regs = p1->p_md.md_regs; 569 570 pmap_activate(&p2->p_vmspace->vm_pmap, &up->u_pcb); 571 572 /* 573 * 574 * Arrange for a non-local goto when the new process 575 * is started, to resume here, returning nonzero from setjmp. 576 */ 577 if (savectx(&up->u_pcb, 1)) { 578 /* 579 * Return 1 in child. 580 */ 581 return (1); 582 } 583 return (0); 584 } 585 586 void 587 cpu_exit(p) 588 register struct proc *p; 589 { 590 591 #if NNPX > 0 592 npxexit(p); 593 #endif /* NNPX */ 594 cnt.v_swtch++; 595 cpu_switch(p); 596 panic("cpu_exit"); 597 } 598 599 void 600 cpu_wait(p) struct proc *p; { 601 /* extern vm_map_t upages_map; */ 602 603 /* drop per-process resources */ 604 pmap_remove(vm_map_pmap(u_map), (vm_offset_t) p->p_addr, 605 ((vm_offset_t) p->p_addr) + ctob(UPAGES)); 606 kmem_free(u_map, (vm_offset_t)p->p_addr, ctob(UPAGES)); 607 vmspace_free(p->p_vmspace); 608 } 609 610 /* 611 * Dump the machine specific header information at the start of a core dump. 612 */ 613 int 614 cpu_coredump(p, vp, cred) 615 struct proc *p; 616 struct vnode *vp; 617 struct ucred *cred; 618 { 619 620 return (vn_rdwr(UIO_WRITE, vp, (caddr_t) p->p_addr, ctob(UPAGES), 621 (off_t)0, UIO_SYSSPACE, IO_NODELOCKED|IO_UNIT, cred, (int *)NULL, 622 p)); 623 } 624 625 /* 626 * Set a red zone in the kernel stack after the u. area. 627 */ 628 void 629 setredzone(pte, vaddr) 630 u_short *pte; 631 caddr_t vaddr; 632 { 633 /* eventually do this by setting up an expand-down stack segment 634 for ss0: selector, allowing stack access down to top of u. 635 this means though that protection violations need to be handled 636 thru a double fault exception that must do an integral task 637 switch to a known good context, within which a dump can be 638 taken. a sensible scheme might be to save the initial context 639 used by sched (that has physical memory mapped 1:1 at bottom) 640 and take the dump while still in mapped mode */ 641 } 642 643 /* 644 * Move pages from one kernel virtual address to another. 645 * Both addresses are assumed to reside in the Sysmap, 646 * and size must be a multiple of CLSIZE. 647 */ 648 649 void 650 pagemove(from, to, size) 651 register caddr_t from, to; 652 int size; 653 { 654 register vm_offset_t pa; 655 656 if (size & CLOFSET) 657 panic("pagemove"); 658 while (size > 0) { 659 pa = pmap_kextract((vm_offset_t)from); 660 if (pa == 0) 661 panic("pagemove 2"); 662 if (pmap_kextract((vm_offset_t)to) != 0) 663 panic("pagemove 3"); 664 pmap_kremove((vm_offset_t)from); 665 pmap_kenter((vm_offset_t)to, pa); 666 from += PAGE_SIZE; 667 to += PAGE_SIZE; 668 size -= PAGE_SIZE; 669 } 670 } 671 672 /* 673 * Convert kernel VA to physical address 674 */ 675 u_long 676 kvtop(void *addr) 677 { 678 vm_offset_t va; 679 680 va = pmap_kextract((vm_offset_t)addr); 681 if (va == 0) 682 panic("kvtop: zero page frame"); 683 return((int)va); 684 } 685 686 /* 687 * Map an IO request into kernel virtual address space. 688 * 689 * All requests are (re)mapped into kernel VA space. 690 * Notice that we use b_bufsize for the size of the buffer 691 * to be mapped. b_bcount might be modified by the driver. 692 */ 693 void 694 vmapbuf(bp) 695 register struct buf *bp; 696 { 697 register int npf; 698 register caddr_t addr; 699 int off; 700 vm_offset_t kva; 701 vm_offset_t pa, v; 702 703 if ((bp->b_flags & B_PHYS) == 0) 704 panic("vmapbuf"); 705 706 /* 707 * this is the kva that is to be used for 708 * the temporary kernel mapping 709 */ 710 kva = (vm_offset_t) bp->b_saveaddr; 711 712 for (addr = (caddr_t)trunc_page(bp->b_data); 713 addr < bp->b_data + bp->b_bufsize; 714 addr += PAGE_SIZE) { 715 716 /* 717 * do the vm_fault if needed, do the copy-on-write thing when 718 * reading stuff off device into memory. 719 */ 720 vm_fault_quick(addr, 721 (bp->b_flags&B_READ)?(VM_PROT_READ|VM_PROT_WRITE):VM_PROT_READ); 722 pa = pmap_kextract((vm_offset_t) addr); 723 if (pa == 0) 724 panic("vmapbuf: page not present"); 725 /* 726 * hold the data page 727 */ 728 #ifdef DIAGNOSTIC 729 if( VM_PAGE_TO_PHYS(PHYS_TO_VM_PAGE(pa)) != pa) 730 panic("vmapbuf: confused PHYS_TO_VM_PAGE mapping"); 731 #endif 732 vm_page_hold(PHYS_TO_VM_PAGE(pa)); 733 } 734 735 addr = bp->b_saveaddr = bp->b_data; 736 off = (int)addr & PGOFSET; 737 npf = btoc(round_page(bp->b_bufsize + off)); 738 bp->b_data = (caddr_t) (kva + off); 739 while (npf--) { 740 pa = pmap_kextract((vm_offset_t)addr); 741 if (pa == 0) 742 panic("vmapbuf: null page frame"); 743 pmap_kenter(kva, trunc_page(pa)); 744 addr += PAGE_SIZE; 745 kva += PAGE_SIZE; 746 } 747 } 748 749 /* 750 * Free the io map PTEs associated with this IO operation. 751 * We also invalidate the TLB entries and restore the original b_addr. 752 */ 753 void 754 vunmapbuf(bp) 755 register struct buf *bp; 756 { 757 register caddr_t addr; 758 vm_offset_t v,pa; 759 760 if ((bp->b_flags & B_PHYS) == 0) 761 panic("vunmapbuf"); 762 763 for (addr = (caddr_t)trunc_page((vm_offset_t) bp->b_data); 764 addr < bp->b_data + bp->b_bufsize; 765 addr += NBPG) 766 pmap_kremove((vm_offset_t) addr); 767 768 bp->b_data = bp->b_saveaddr; 769 bp->b_saveaddr = NULL; 770 771 /* 772 * unhold the pde, and data pages 773 */ 774 for (addr = (caddr_t)trunc_page((vm_offset_t) bp->b_data); 775 addr < bp->b_data + bp->b_bufsize; 776 addr += NBPG) { 777 /* 778 * release the data page 779 */ 780 pa = pmap_kextract((vm_offset_t) addr); 781 vm_page_unhold(PHYS_TO_VM_PAGE(pa)); 782 } 783 } 784 785 /* 786 * Force reset the processor by invalidating the entire address space! 787 */ 788 void 789 cpu_reset() { 790 791 /* 792 * Attempt to do a CPU reset via the keyboard controller, 793 * do not turn of the GateA20, as any machine that fails 794 * to do the reset here would then end up in no man's land. 795 */ 796 797 #ifndef BROKEN_KEYBOARD_RESET 798 outb(IO_KBD + 4, 0xFE); 799 DELAY(500000); /* wait 0.5 sec to see if that did it */ 800 printf("Keyboard reset did not work, attempting CPU shutdown\n"); 801 DELAY(1000000); /* wait 1 sec for printf to complete */ 802 #endif 803 804 /* force a shutdown by unmapping entire address space ! */ 805 bzero((caddr_t) PTD, NBPG); 806 807 /* "good night, sweet prince .... <THUNK!>" */ 808 pmap_update(); 809 /* NOTREACHED */ 810 while(1); 811 } 812 813 /* 814 * Grow the user stack to allow for 'sp'. This version grows the stack in 815 * chunks of SGROWSIZ. 816 */ 817 int 818 grow(p, sp) 819 struct proc *p; 820 u_int sp; 821 { 822 unsigned int nss; 823 caddr_t v; 824 struct vmspace *vm = p->p_vmspace; 825 826 if ((caddr_t)sp <= vm->vm_maxsaddr || (unsigned)sp >= (unsigned)USRSTACK) 827 return (1); 828 829 nss = roundup(USRSTACK - (unsigned)sp, PAGE_SIZE); 830 831 if (nss > p->p_rlimit[RLIMIT_STACK].rlim_cur) 832 return (0); 833 834 if (vm->vm_ssize && roundup(vm->vm_ssize << PAGE_SHIFT, 835 SGROWSIZ) < nss) { 836 int grow_amount; 837 /* 838 * If necessary, grow the VM that the stack occupies 839 * to allow for the rlimit. This allows us to not have 840 * to allocate all of the VM up-front in execve (which 841 * is expensive). 842 * Grow the VM by the amount requested rounded up to 843 * the nearest SGROWSIZ to provide for some hysteresis. 844 */ 845 grow_amount = roundup((nss - (vm->vm_ssize << PAGE_SHIFT)), SGROWSIZ); 846 v = (char *)USRSTACK - roundup(vm->vm_ssize << PAGE_SHIFT, 847 SGROWSIZ) - grow_amount; 848 /* 849 * If there isn't enough room to extend by SGROWSIZ, then 850 * just extend to the maximum size 851 */ 852 if (v < vm->vm_maxsaddr) { 853 v = vm->vm_maxsaddr; 854 grow_amount = MAXSSIZ - (vm->vm_ssize << PAGE_SHIFT); 855 } 856 if ((grow_amount == 0) || (vm_map_find(&vm->vm_map, NULL, 0, (vm_offset_t *)&v, 857 grow_amount, FALSE) != KERN_SUCCESS)) { 858 return (0); 859 } 860 vm->vm_ssize += grow_amount >> PAGE_SHIFT; 861 } 862 863 return (1); 864 } 865 866 /* 867 * prototype routine to implement the pre-zeroed page mechanism 868 * this routine is called from the idle loop. 869 */ 870 int 871 vm_page_zero_idle() { 872 vm_page_t m; 873 if ((cnt.v_free_count > cnt.v_interrupt_free_min) && 874 (m = vm_page_queue_free.tqh_first)) { 875 TAILQ_REMOVE(&vm_page_queue_free, m, pageq); 876 enable_intr(); 877 pmap_zero_page(VM_PAGE_TO_PHYS(m)); 878 disable_intr(); 879 TAILQ_INSERT_HEAD(&vm_page_queue_zero, m, pageq); 880 return 1; 881 } 882 return 0; 883 } 884