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 1.44 1995/11/18 06:54:11 bde 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 extern void pagemove __P((caddr_t from, caddr_t to, int size)); 64 extern void setredzone __P((u_short *pte, caddr_t vaddr)); 65 extern void vm_fault_quick __P((caddr_t v, int prot)); 66 67 #ifdef BOUNCE_BUFFERS 68 extern vm_offset_t 69 vm_bounce_kva __P((int size, int waitok)); 70 extern void vm_bounce_kva_free __P((vm_offset_t addr, vm_offset_t size, 71 int now)); 72 extern vm_offset_t 73 vm_bounce_page_find __P((int count)); 74 extern void vm_bounce_page_free __P((vm_offset_t pa, int count)); 75 76 volatile int kvasfreecnt; 77 78 caddr_t bouncememory; 79 int bouncepages, bpwait; 80 vm_offset_t *bouncepa; 81 int bmwait, bmfreeing; 82 83 #define BITS_IN_UNSIGNED (8*sizeof(unsigned)) 84 int bounceallocarraysize; 85 unsigned *bounceallocarray; 86 int bouncefree; 87 88 #define SIXTEENMEG (4096*4096) 89 #define MAXBKVA 1024 90 int maxbkva = MAXBKVA*NBPG; 91 92 /* special list that can be used at interrupt time for eventual kva free */ 93 struct kvasfree { 94 vm_offset_t addr; 95 vm_offset_t size; 96 } kvaf[MAXBKVA]; 97 98 /* 99 * get bounce buffer pages (count physically contiguous) 100 * (only 1 inplemented now) 101 */ 102 vm_offset_t 103 vm_bounce_page_find(count) 104 int count; 105 { 106 int bit; 107 int s,i; 108 109 if (count != 1) 110 panic("vm_bounce_page_find -- no support for > 1 page yet!!!"); 111 112 s = splbio(); 113 retry: 114 for (i = 0; i < bounceallocarraysize; i++) { 115 if (bounceallocarray[i] != 0xffffffff) { 116 bit = ffs(~bounceallocarray[i]); 117 if (bit) { 118 bounceallocarray[i] |= 1 << (bit - 1) ; 119 bouncefree -= count; 120 splx(s); 121 return bouncepa[(i * BITS_IN_UNSIGNED + (bit - 1))]; 122 } 123 } 124 } 125 bpwait = 1; 126 tsleep((caddr_t) &bounceallocarray, PRIBIO, "bncwai", 0); 127 goto retry; 128 } 129 130 void 131 vm_bounce_kva_free(addr, size, now) 132 vm_offset_t addr; 133 vm_offset_t size; 134 int now; 135 { 136 int s = splbio(); 137 kvaf[kvasfreecnt].addr = addr; 138 kvaf[kvasfreecnt].size = size; 139 ++kvasfreecnt; 140 if( now) { 141 /* 142 * this will do wakeups 143 */ 144 vm_bounce_kva(0,0); 145 } else { 146 if (bmwait) { 147 /* 148 * if anyone is waiting on the bounce-map, then wakeup 149 */ 150 wakeup((caddr_t) io_map); 151 bmwait = 0; 152 } 153 } 154 splx(s); 155 } 156 157 /* 158 * free count bounce buffer pages 159 */ 160 void 161 vm_bounce_page_free(pa, count) 162 vm_offset_t pa; 163 int count; 164 { 165 int allocindex; 166 int index; 167 int bit; 168 169 if (count != 1) 170 panic("vm_bounce_page_free -- no support for > 1 page yet!!!"); 171 172 for(index=0;index<bouncepages;index++) { 173 if( pa == bouncepa[index]) 174 break; 175 } 176 177 if( index == bouncepages) 178 panic("vm_bounce_page_free: invalid bounce buffer"); 179 180 allocindex = index / BITS_IN_UNSIGNED; 181 bit = index % BITS_IN_UNSIGNED; 182 183 bounceallocarray[allocindex] &= ~(1 << bit); 184 185 bouncefree += count; 186 if (bpwait) { 187 bpwait = 0; 188 wakeup((caddr_t) &bounceallocarray); 189 } 190 } 191 192 /* 193 * allocate count bounce buffer kva pages 194 */ 195 vm_offset_t 196 vm_bounce_kva(size, waitok) 197 int size; 198 int waitok; 199 { 200 int i; 201 vm_offset_t kva = 0; 202 vm_offset_t off; 203 int s = splbio(); 204 more: 205 if (!bmfreeing && kvasfreecnt) { 206 bmfreeing = 1; 207 for (i = 0; i < kvasfreecnt; i++) { 208 for(off=0;off<kvaf[i].size;off+=NBPG) { 209 pmap_kremove( kvaf[i].addr + off); 210 } 211 kmem_free_wakeup(io_map, kvaf[i].addr, 212 kvaf[i].size); 213 } 214 kvasfreecnt = 0; 215 bmfreeing = 0; 216 if( bmwait) { 217 bmwait = 0; 218 wakeup( (caddr_t) io_map); 219 } 220 } 221 222 if( size == 0) { 223 splx(s); 224 return NULL; 225 } 226 227 if ((kva = kmem_alloc_pageable(io_map, size)) == 0) { 228 if( !waitok) { 229 splx(s); 230 return NULL; 231 } 232 bmwait = 1; 233 tsleep((caddr_t) io_map, PRIBIO, "bmwait", 0); 234 goto more; 235 } 236 splx(s); 237 return kva; 238 } 239 240 /* 241 * same as vm_bounce_kva -- but really allocate (but takes pages as arg) 242 */ 243 vm_offset_t 244 vm_bounce_kva_alloc(count) 245 int count; 246 { 247 int i; 248 vm_offset_t kva; 249 vm_offset_t pa; 250 if( bouncepages == 0) { 251 kva = (vm_offset_t) malloc(count*NBPG, M_TEMP, M_WAITOK); 252 return kva; 253 } 254 kva = vm_bounce_kva(count*NBPG, 1); 255 for(i=0;i<count;i++) { 256 pa = vm_bounce_page_find(1); 257 pmap_kenter(kva + i * NBPG, pa); 258 } 259 return kva; 260 } 261 262 /* 263 * same as vm_bounce_kva_free -- but really free 264 */ 265 void 266 vm_bounce_kva_alloc_free(kva, count) 267 vm_offset_t kva; 268 int count; 269 { 270 int i; 271 vm_offset_t pa; 272 if( bouncepages == 0) { 273 free((caddr_t) kva, M_TEMP); 274 return; 275 } 276 for(i = 0; i < count; i++) { 277 pa = pmap_kextract(kva + i * NBPG); 278 vm_bounce_page_free(pa, 1); 279 } 280 vm_bounce_kva_free(kva, count*NBPG, 0); 281 } 282 283 /* 284 * do the things necessary to the struct buf to implement 285 * bounce buffers... inserted before the disk sort 286 */ 287 void 288 vm_bounce_alloc(bp) 289 struct buf *bp; 290 { 291 int countvmpg; 292 vm_offset_t vastart, vaend; 293 vm_offset_t vapstart, vapend; 294 vm_offset_t va, kva; 295 vm_offset_t pa; 296 int dobounceflag = 0; 297 int i; 298 299 if (bouncepages == 0) 300 return; 301 302 if (bp->b_flags & B_BOUNCE) { 303 printf("vm_bounce_alloc: called recursively???\n"); 304 return; 305 } 306 307 if (bp->b_bufsize < bp->b_bcount) { 308 printf( 309 "vm_bounce_alloc: b_bufsize(0x%lx) < b_bcount(0x%lx) !!\n", 310 bp->b_bufsize, bp->b_bcount); 311 panic("vm_bounce_alloc"); 312 } 313 314 /* 315 * This is not really necessary 316 * if( bp->b_bufsize != bp->b_bcount) { 317 * printf("size: %d, count: %d\n", bp->b_bufsize, bp->b_bcount); 318 * } 319 */ 320 321 322 vastart = (vm_offset_t) bp->b_data; 323 vaend = (vm_offset_t) bp->b_data + bp->b_bufsize; 324 325 vapstart = i386_trunc_page(vastart); 326 vapend = i386_round_page(vaend); 327 countvmpg = (vapend - vapstart) / NBPG; 328 329 /* 330 * if any page is above 16MB, then go into bounce-buffer mode 331 */ 332 va = vapstart; 333 for (i = 0; i < countvmpg; i++) { 334 pa = pmap_kextract(va); 335 if (pa >= SIXTEENMEG) 336 ++dobounceflag; 337 if( pa == 0) 338 panic("vm_bounce_alloc: Unmapped page"); 339 va += NBPG; 340 } 341 if (dobounceflag == 0) 342 return; 343 344 if (bouncepages < dobounceflag) 345 panic("Not enough bounce buffers!!!"); 346 347 /* 348 * allocate a replacement kva for b_addr 349 */ 350 kva = vm_bounce_kva(countvmpg*NBPG, 1); 351 #if 0 352 printf("%s: vapstart: %x, vapend: %x, countvmpg: %d, kva: %x ", 353 (bp->b_flags & B_READ) ? "read":"write", 354 vapstart, vapend, countvmpg, kva); 355 #endif 356 va = vapstart; 357 for (i = 0; i < countvmpg; i++) { 358 pa = pmap_kextract(va); 359 if (pa >= SIXTEENMEG) { 360 /* 361 * allocate a replacement page 362 */ 363 vm_offset_t bpa = vm_bounce_page_find(1); 364 pmap_kenter(kva + (NBPG * i), bpa); 365 #if 0 366 printf("r(%d): (%x,%x,%x) ", i, va, pa, bpa); 367 #endif 368 /* 369 * if we are writing, the copy the data into the page 370 */ 371 if ((bp->b_flags & B_READ) == 0) { 372 bcopy((caddr_t) va, (caddr_t) kva + (NBPG * i), NBPG); 373 } 374 } else { 375 /* 376 * use original page 377 */ 378 pmap_kenter(kva + (NBPG * i), pa); 379 } 380 va += NBPG; 381 } 382 383 /* 384 * flag the buffer as being bounced 385 */ 386 bp->b_flags |= B_BOUNCE; 387 /* 388 * save the original buffer kva 389 */ 390 bp->b_savekva = bp->b_data; 391 /* 392 * put our new kva into the buffer (offset by original offset) 393 */ 394 bp->b_data = (caddr_t) (((vm_offset_t) kva) | 395 ((vm_offset_t) bp->b_savekva & (NBPG - 1))); 396 #if 0 397 printf("b_savekva: %x, newva: %x\n", bp->b_savekva, bp->b_data); 398 #endif 399 return; 400 } 401 402 /* 403 * hook into biodone to free bounce buffer 404 */ 405 void 406 vm_bounce_free(bp) 407 struct buf *bp; 408 { 409 int i; 410 vm_offset_t origkva, bouncekva, bouncekvaend; 411 412 /* 413 * if this isn't a bounced buffer, then just return 414 */ 415 if ((bp->b_flags & B_BOUNCE) == 0) 416 return; 417 418 /* 419 * This check is not necessary 420 * if (bp->b_bufsize != bp->b_bcount) { 421 * printf("vm_bounce_free: b_bufsize=%d, b_bcount=%d\n", 422 * bp->b_bufsize, bp->b_bcount); 423 * } 424 */ 425 426 origkva = (vm_offset_t) bp->b_savekva; 427 bouncekva = (vm_offset_t) bp->b_data; 428 /* 429 printf("free: %d ", bp->b_bufsize); 430 */ 431 432 /* 433 * check every page in the kva space for b_addr 434 */ 435 for (i = 0; i < bp->b_bufsize; ) { 436 vm_offset_t mybouncepa; 437 vm_offset_t copycount; 438 439 copycount = i386_round_page(bouncekva + 1) - bouncekva; 440 mybouncepa = pmap_kextract(i386_trunc_page(bouncekva)); 441 442 /* 443 * if this is a bounced pa, then process as one 444 */ 445 if ( mybouncepa != pmap_kextract( i386_trunc_page( origkva))) { 446 vm_offset_t tocopy = copycount; 447 if (i + tocopy > bp->b_bufsize) 448 tocopy = bp->b_bufsize - i; 449 /* 450 * if this is a read, then copy from bounce buffer into original buffer 451 */ 452 if (bp->b_flags & B_READ) 453 bcopy((caddr_t) bouncekva, (caddr_t) origkva, tocopy); 454 /* 455 * free the bounce allocation 456 */ 457 458 /* 459 printf("(kva: %x, pa: %x)", bouncekva, mybouncepa); 460 */ 461 vm_bounce_page_free(mybouncepa, 1); 462 } 463 464 origkva += copycount; 465 bouncekva += copycount; 466 i += copycount; 467 } 468 469 /* 470 printf("\n"); 471 */ 472 /* 473 * add the old kva into the "to free" list 474 */ 475 476 bouncekva= i386_trunc_page((vm_offset_t) bp->b_data); 477 bouncekvaend= i386_round_page((vm_offset_t)bp->b_data + bp->b_bufsize); 478 479 /* 480 printf("freeva: %d\n", (bouncekvaend - bouncekva) / NBPG); 481 */ 482 vm_bounce_kva_free( bouncekva, (bouncekvaend - bouncekva), 0); 483 bp->b_data = bp->b_savekva; 484 bp->b_savekva = 0; 485 bp->b_flags &= ~B_BOUNCE; 486 487 return; 488 } 489 490 491 /* 492 * init the bounce buffer system 493 */ 494 void 495 vm_bounce_init() 496 { 497 int i; 498 499 kvasfreecnt = 0; 500 501 if (bouncepages == 0) 502 return; 503 504 bounceallocarraysize = (bouncepages + BITS_IN_UNSIGNED - 1) / BITS_IN_UNSIGNED; 505 bounceallocarray = malloc(bounceallocarraysize * sizeof(unsigned), M_TEMP, M_NOWAIT); 506 507 if (!bounceallocarray) 508 panic("Cannot allocate bounce resource array"); 509 510 bouncepa = malloc(bouncepages * sizeof(vm_offset_t), M_TEMP, M_NOWAIT); 511 if (!bouncepa) 512 panic("Cannot allocate physical memory array"); 513 514 for(i=0;i<bounceallocarraysize;i++) { 515 bounceallocarray[i] = 0xffffffff; 516 } 517 518 for(i=0;i<bouncepages;i++) { 519 vm_offset_t pa; 520 if( (pa = pmap_kextract((vm_offset_t) bouncememory + i * NBPG)) >= SIXTEENMEG) 521 panic("bounce memory out of range"); 522 if( pa == 0) 523 panic("bounce memory not resident"); 524 bouncepa[i] = pa; 525 bounceallocarray[i/(8*sizeof(int))] &= ~(1<<(i%(8*sizeof(int)))); 526 } 527 bouncefree = bouncepages; 528 529 } 530 #endif /* BOUNCE_BUFFERS */ 531 532 /* 533 * quick version of vm_fault 534 */ 535 void 536 vm_fault_quick(v, prot) 537 caddr_t v; 538 int prot; 539 { 540 if (prot & VM_PROT_WRITE) 541 subyte(v, fubyte(v)); 542 else 543 fubyte(v); 544 } 545 546 /* 547 * Finish a fork operation, with process p2 nearly set up. 548 * Copy and update the kernel stack and pcb, making the child 549 * ready to run, and marking it so that it can return differently 550 * than the parent. Returns 1 in the child process, 0 in the parent. 551 * We currently double-map the user area so that the stack is at the same 552 * address in each process; in the future we will probably relocate 553 * the frame pointers on the stack after copying. 554 */ 555 int 556 cpu_fork(p1, p2) 557 register struct proc *p1, *p2; 558 { 559 register struct user *up = p2->p_addr; 560 int offset; 561 562 /* 563 * Copy pcb and stack from proc p1 to p2. 564 * We do this as cheaply as possible, copying only the active 565 * part of the stack. The stack and pcb need to agree; 566 * this is tricky, as the final pcb is constructed by savectx, 567 * but its frame isn't yet on the stack when the stack is copied. 568 * swtch compensates for this when the child eventually runs. 569 * This should be done differently, with a single call 570 * that copies and updates the pcb+stack, 571 * replacing the bcopy and savectx. 572 */ 573 p2->p_addr->u_pcb = p1->p_addr->u_pcb; 574 offset = mvesp() - (int)kstack; 575 bcopy((caddr_t)kstack + offset, (caddr_t)p2->p_addr + offset, 576 (unsigned) ctob(UPAGES) - offset); 577 p2->p_md.md_regs = p1->p_md.md_regs; 578 579 pmap_activate(&p2->p_vmspace->vm_pmap, &up->u_pcb); 580 581 /* 582 * 583 * Arrange for a non-local goto when the new process 584 * is started, to resume here, returning nonzero from setjmp. 585 */ 586 if (savectx(&up->u_pcb, 1)) { 587 /* 588 * Return 1 in child. 589 */ 590 return (1); 591 } 592 return (0); 593 } 594 595 void 596 cpu_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 } 607 608 void 609 cpu_wait(p) struct proc *p; { 610 /* extern vm_map_t upages_map; */ 611 612 /* drop per-process resources */ 613 pmap_remove(vm_map_pmap(u_map), (vm_offset_t) p->p_addr, 614 ((vm_offset_t) p->p_addr) + ctob(UPAGES)); 615 kmem_free(u_map, (vm_offset_t)p->p_addr, ctob(UPAGES)); 616 vmspace_free(p->p_vmspace); 617 } 618 619 /* 620 * Dump the machine specific header information at the start of a core dump. 621 */ 622 int 623 cpu_coredump(p, vp, cred) 624 struct proc *p; 625 struct vnode *vp; 626 struct ucred *cred; 627 { 628 629 return (vn_rdwr(UIO_WRITE, vp, (caddr_t) p->p_addr, ctob(UPAGES), 630 (off_t)0, UIO_SYSSPACE, IO_NODELOCKED|IO_UNIT, cred, (int *)NULL, 631 p)); 632 } 633 634 /* 635 * Set a red zone in the kernel stack after the u. area. 636 */ 637 void 638 setredzone(pte, vaddr) 639 u_short *pte; 640 caddr_t vaddr; 641 { 642 /* eventually do this by setting up an expand-down stack segment 643 for ss0: selector, allowing stack access down to top of u. 644 this means though that protection violations need to be handled 645 thru a double fault exception that must do an integral task 646 switch to a known good context, within which a dump can be 647 taken. a sensible scheme might be to save the initial context 648 used by sched (that has physical memory mapped 1:1 at bottom) 649 and take the dump while still in mapped mode */ 650 } 651 652 /* 653 * Move pages from one kernel virtual address to another. 654 * Both addresses are assumed to reside in the Sysmap, 655 * and size must be a multiple of CLSIZE. 656 */ 657 658 void 659 pagemove(from, to, size) 660 register caddr_t from, to; 661 int size; 662 { 663 register vm_offset_t pa; 664 665 if (size & CLOFSET) 666 panic("pagemove"); 667 while (size > 0) { 668 pa = pmap_kextract((vm_offset_t)from); 669 if (pa == 0) 670 panic("pagemove 2"); 671 if (pmap_kextract((vm_offset_t)to) != 0) 672 panic("pagemove 3"); 673 pmap_kremove((vm_offset_t)from); 674 pmap_kenter((vm_offset_t)to, pa); 675 from += PAGE_SIZE; 676 to += PAGE_SIZE; 677 size -= PAGE_SIZE; 678 } 679 } 680 681 /* 682 * Convert kernel VA to physical address 683 */ 684 u_long 685 kvtop(void *addr) 686 { 687 vm_offset_t va; 688 689 va = pmap_kextract((vm_offset_t)addr); 690 if (va == 0) 691 panic("kvtop: zero page frame"); 692 return((int)va); 693 } 694 695 /* 696 * Map an IO request into kernel virtual address space. 697 * 698 * All requests are (re)mapped into kernel VA space. 699 * Notice that we use b_bufsize for the size of the buffer 700 * to be mapped. b_bcount might be modified by the driver. 701 */ 702 void 703 vmapbuf(bp) 704 register struct buf *bp; 705 { 706 register int npf; 707 register caddr_t addr; 708 int off; 709 vm_offset_t kva; 710 vm_offset_t pa; 711 712 if ((bp->b_flags & B_PHYS) == 0) 713 panic("vmapbuf"); 714 715 /* 716 * this is the kva that is to be used for 717 * the temporary kernel mapping 718 */ 719 kva = (vm_offset_t) bp->b_saveaddr; 720 721 for (addr = (caddr_t)trunc_page(bp->b_data); 722 addr < bp->b_data + bp->b_bufsize; 723 addr += PAGE_SIZE) { 724 725 /* 726 * do the vm_fault if needed, do the copy-on-write thing when 727 * reading stuff off device into memory. 728 */ 729 vm_fault_quick(addr, 730 (bp->b_flags&B_READ)?(VM_PROT_READ|VM_PROT_WRITE):VM_PROT_READ); 731 pa = pmap_kextract((vm_offset_t) addr); 732 if (pa == 0) 733 panic("vmapbuf: page not present"); 734 /* 735 * hold the data page 736 */ 737 #ifdef DIAGNOSTIC 738 if( VM_PAGE_TO_PHYS(PHYS_TO_VM_PAGE(pa)) != pa) 739 panic("vmapbuf: confused PHYS_TO_VM_PAGE mapping"); 740 #endif 741 vm_page_hold(PHYS_TO_VM_PAGE(pa)); 742 } 743 744 addr = bp->b_saveaddr = bp->b_data; 745 off = (int)addr & PGOFSET; 746 npf = btoc(round_page(bp->b_bufsize + off)); 747 bp->b_data = (caddr_t) (kva + off); 748 while (npf--) { 749 pa = pmap_kextract((vm_offset_t)addr); 750 if (pa == 0) 751 panic("vmapbuf: null page frame"); 752 pmap_kenter(kva, trunc_page(pa)); 753 addr += PAGE_SIZE; 754 kva += PAGE_SIZE; 755 } 756 } 757 758 /* 759 * Free the io map PTEs associated with this IO operation. 760 * We also invalidate the TLB entries and restore the original b_addr. 761 */ 762 void 763 vunmapbuf(bp) 764 register struct buf *bp; 765 { 766 register caddr_t addr; 767 vm_offset_t pa; 768 769 if ((bp->b_flags & B_PHYS) == 0) 770 panic("vunmapbuf"); 771 772 for (addr = (caddr_t)trunc_page((vm_offset_t) bp->b_data); 773 addr < bp->b_data + bp->b_bufsize; 774 addr += NBPG) 775 pmap_kremove((vm_offset_t) addr); 776 777 bp->b_data = bp->b_saveaddr; 778 bp->b_saveaddr = NULL; 779 780 /* 781 * unhold the pde, and data pages 782 */ 783 for (addr = (caddr_t)trunc_page((vm_offset_t) bp->b_data); 784 addr < bp->b_data + bp->b_bufsize; 785 addr += NBPG) { 786 /* 787 * release the data page 788 */ 789 pa = pmap_kextract((vm_offset_t) addr); 790 vm_page_unhold(PHYS_TO_VM_PAGE(pa)); 791 } 792 } 793 794 /* 795 * Force reset the processor by invalidating the entire address space! 796 */ 797 void 798 cpu_reset() { 799 800 /* 801 * Attempt to do a CPU reset via the keyboard controller, 802 * do not turn of the GateA20, as any machine that fails 803 * to do the reset here would then end up in no man's land. 804 */ 805 806 #ifndef BROKEN_KEYBOARD_RESET 807 outb(IO_KBD + 4, 0xFE); 808 DELAY(500000); /* wait 0.5 sec to see if that did it */ 809 printf("Keyboard reset did not work, attempting CPU shutdown\n"); 810 DELAY(1000000); /* wait 1 sec for printf to complete */ 811 #endif 812 813 /* force a shutdown by unmapping entire address space ! */ 814 bzero((caddr_t) PTD, NBPG); 815 816 /* "good night, sweet prince .... <THUNK!>" */ 817 pmap_update(); 818 /* NOTREACHED */ 819 while(1); 820 } 821 822 /* 823 * Grow the user stack to allow for 'sp'. This version grows the stack in 824 * chunks of SGROWSIZ. 825 */ 826 int 827 grow(p, sp) 828 struct proc *p; 829 u_int sp; 830 { 831 unsigned int nss; 832 caddr_t v; 833 struct vmspace *vm = p->p_vmspace; 834 835 if ((caddr_t)sp <= vm->vm_maxsaddr || (unsigned)sp >= (unsigned)USRSTACK) 836 return (1); 837 838 nss = roundup(USRSTACK - (unsigned)sp, PAGE_SIZE); 839 840 if (nss > p->p_rlimit[RLIMIT_STACK].rlim_cur) 841 return (0); 842 843 if (vm->vm_ssize && roundup(vm->vm_ssize << PAGE_SHIFT, 844 SGROWSIZ) < nss) { 845 int grow_amount; 846 /* 847 * If necessary, grow the VM that the stack occupies 848 * to allow for the rlimit. This allows us to not have 849 * to allocate all of the VM up-front in execve (which 850 * is expensive). 851 * Grow the VM by the amount requested rounded up to 852 * the nearest SGROWSIZ to provide for some hysteresis. 853 */ 854 grow_amount = roundup((nss - (vm->vm_ssize << PAGE_SHIFT)), SGROWSIZ); 855 v = (char *)USRSTACK - roundup(vm->vm_ssize << PAGE_SHIFT, 856 SGROWSIZ) - grow_amount; 857 /* 858 * If there isn't enough room to extend by SGROWSIZ, then 859 * just extend to the maximum size 860 */ 861 if (v < vm->vm_maxsaddr) { 862 v = vm->vm_maxsaddr; 863 grow_amount = MAXSSIZ - (vm->vm_ssize << PAGE_SHIFT); 864 } 865 if ((grow_amount == 0) || (vm_map_find(&vm->vm_map, NULL, 0, (vm_offset_t *)&v, 866 grow_amount, FALSE) != KERN_SUCCESS)) { 867 return (0); 868 } 869 vm->vm_ssize += grow_amount >> PAGE_SHIFT; 870 } 871 872 return (1); 873 } 874 875 /* 876 * prototype routine to implement the pre-zeroed page mechanism 877 * this routine is called from the idle loop. 878 */ 879 int 880 vm_page_zero_idle() { 881 vm_page_t m; 882 if ((cnt.v_free_count > cnt.v_interrupt_free_min) && 883 (m = vm_page_queue_free.tqh_first)) { 884 TAILQ_REMOVE(&vm_page_queue_free, m, pageq); 885 enable_intr(); 886 pmap_zero_page(VM_PAGE_TO_PHYS(m)); 887 disable_intr(); 888 TAILQ_INSERT_HEAD(&vm_page_queue_zero, m, pageq); 889 return 1; 890 } 891 return 0; 892 } 893