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 1.29 1994/10/08 22:19:51 phk 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 #ifdef BOUNCE_BUFFERS 59 vm_map_t io_map; 60 volatile int kvasfreecnt; 61 62 63 caddr_t bouncememory; 64 int bouncepages, bpwait; 65 vm_offset_t *bouncepa; 66 int bmwait, bmfreeing; 67 68 #define BITS_IN_UNSIGNED (8*sizeof(unsigned)) 69 int bounceallocarraysize; 70 unsigned *bounceallocarray; 71 int bouncefree; 72 73 #define SIXTEENMEG (4096*4096) 74 #define MAXBKVA 1024 75 int maxbkva = MAXBKVA*NBPG; 76 77 /* special list that can be used at interrupt time for eventual kva free */ 78 struct kvasfree { 79 vm_offset_t addr; 80 vm_offset_t size; 81 } kvaf[MAXBKVA]; 82 83 84 vm_offset_t vm_bounce_kva(); 85 /* 86 * get bounce buffer pages (count physically contiguous) 87 * (only 1 inplemented now) 88 */ 89 vm_offset_t 90 vm_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(); 100 retry: 101 for (i = 0; i < bounceallocarraysize; i++) { 102 if (bounceallocarray[i] != 0xffffffff) { 103 bit = ffs(~bounceallocarray[i]); 104 if (bit) { 105 bounceallocarray[i] |= 1 << (bit - 1) ; 106 bouncefree -= count; 107 splx(s); 108 return bouncepa[(i * BITS_IN_UNSIGNED + (bit - 1))]; 109 } 110 } 111 } 112 bpwait = 1; 113 tsleep((caddr_t) &bounceallocarray, PRIBIO, "bncwai", 0); 114 goto retry; 115 } 116 117 void 118 vm_bounce_kva_free(addr, size, now) 119 vm_offset_t addr; 120 vm_offset_t size; 121 int now; 122 { 123 int s = splbio(); 124 kvaf[kvasfreecnt].addr = addr; 125 kvaf[kvasfreecnt].size = size; 126 ++kvasfreecnt; 127 if( now) { 128 /* 129 * this will do wakeups 130 */ 131 vm_bounce_kva(0,0); 132 } else { 133 if (bmwait) { 134 /* 135 * if anyone is waiting on the bounce-map, then wakeup 136 */ 137 wakeup((caddr_t) io_map); 138 bmwait = 0; 139 } 140 } 141 splx(s); 142 } 143 144 /* 145 * free count bounce buffer pages 146 */ 147 void 148 vm_bounce_page_free(pa, count) 149 vm_offset_t pa; 150 int count; 151 { 152 int allocindex; 153 int index; 154 int bit; 155 156 if (count != 1) 157 panic("vm_bounce_page_free -- no support for > 1 page yet!!!\n"); 158 159 for(index=0;index<bouncepages;index++) { 160 if( pa == bouncepa[index]) 161 break; 162 } 163 164 if( index == bouncepages) 165 panic("vm_bounce_page_free: invalid bounce buffer"); 166 167 allocindex = index / BITS_IN_UNSIGNED; 168 bit = index % BITS_IN_UNSIGNED; 169 170 bounceallocarray[allocindex] &= ~(1 << bit); 171 172 bouncefree += count; 173 if (bpwait) { 174 bpwait = 0; 175 wakeup((caddr_t) &bounceallocarray); 176 } 177 } 178 179 /* 180 * allocate count bounce buffer kva pages 181 */ 182 vm_offset_t 183 vm_bounce_kva(size, waitok) 184 int size; 185 int waitok; 186 { 187 int i; 188 vm_offset_t kva = 0; 189 vm_offset_t off; 190 int s = splbio(); 191 more: 192 if (!bmfreeing && kvasfreecnt) { 193 bmfreeing = 1; 194 for (i = 0; i < kvasfreecnt; i++) { 195 for(off=0;off<kvaf[i].size;off+=NBPG) { 196 pmap_kremove( kvaf[i].addr + off); 197 } 198 kmem_free_wakeup(io_map, kvaf[i].addr, 199 kvaf[i].size); 200 } 201 kvasfreecnt = 0; 202 bmfreeing = 0; 203 if( bmwait) { 204 bmwait = 0; 205 wakeup( (caddr_t) io_map); 206 } 207 } 208 209 if( size == 0) { 210 splx(s); 211 return NULL; 212 } 213 214 if ((kva = kmem_alloc_pageable(io_map, size)) == 0) { 215 if( !waitok) { 216 splx(s); 217 return NULL; 218 } 219 bmwait = 1; 220 tsleep((caddr_t) io_map, PRIBIO, "bmwait", 0); 221 goto more; 222 } 223 splx(s); 224 return kva; 225 } 226 227 /* 228 * same as vm_bounce_kva -- but really allocate (but takes pages as arg) 229 */ 230 vm_offset_t 231 vm_bounce_kva_alloc(count) 232 int count; 233 { 234 int i; 235 vm_offset_t kva; 236 vm_offset_t pa; 237 if( bouncepages == 0) { 238 kva = (vm_offset_t) malloc(count*NBPG, M_TEMP, M_WAITOK); 239 return kva; 240 } 241 kva = vm_bounce_kva(count*NBPG, 1); 242 for(i=0;i<count;i++) { 243 pa = vm_bounce_page_find(1); 244 pmap_kenter(kva + i * NBPG, pa); 245 } 246 return kva; 247 } 248 249 /* 250 * same as vm_bounce_kva_free -- but really free 251 */ 252 void 253 vm_bounce_kva_alloc_free(kva, count) 254 vm_offset_t kva; 255 int count; 256 { 257 int i; 258 vm_offset_t pa; 259 if( bouncepages == 0) { 260 free((caddr_t) kva, M_TEMP); 261 return; 262 } 263 for(i = 0; i < count; i++) { 264 pa = pmap_kextract(kva + i * NBPG); 265 vm_bounce_page_free(pa, 1); 266 } 267 vm_bounce_kva_free(kva, count*NBPG, 0); 268 } 269 270 /* 271 * do the things necessary to the struct buf to implement 272 * bounce buffers... inserted before the disk sort 273 */ 274 void 275 vm_bounce_alloc(bp) 276 struct buf *bp; 277 { 278 int countvmpg; 279 vm_offset_t vastart, vaend; 280 vm_offset_t vapstart, vapend; 281 vm_offset_t va, kva; 282 vm_offset_t pa; 283 int dobounceflag = 0; 284 int i; 285 286 if (bouncepages == 0) 287 return; 288 289 if (bp->b_flags & B_BOUNCE) { 290 printf("vm_bounce_alloc: called recursively???\n"); 291 return; 292 } 293 294 if (bp->b_bufsize < bp->b_bcount) { 295 printf( 296 "vm_bounce_alloc: b_bufsize(0x%lx) < b_bcount(0x%lx) !!\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 if( pa == 0) 325 panic("vm_bounce_alloc: Unmapped page"); 326 va += NBPG; 327 } 328 if (dobounceflag == 0) 329 return; 330 331 if (bouncepages < dobounceflag) 332 panic("Not enough bounce buffers!!!"); 333 334 /* 335 * allocate a replacement kva for b_addr 336 */ 337 kva = vm_bounce_kva(countvmpg*NBPG, 1); 338 #if 0 339 printf("%s: vapstart: %x, vapend: %x, countvmpg: %d, kva: %x ", 340 (bp->b_flags & B_READ) ? "read":"write", 341 vapstart, vapend, countvmpg, kva); 342 #endif 343 va = vapstart; 344 for (i = 0; i < countvmpg; i++) { 345 pa = pmap_kextract(va); 346 if (pa >= SIXTEENMEG) { 347 /* 348 * allocate a replacement page 349 */ 350 vm_offset_t bpa = vm_bounce_page_find(1); 351 pmap_kenter(kva + (NBPG * i), bpa); 352 #if 0 353 printf("r(%d): (%x,%x,%x) ", i, va, pa, bpa); 354 #endif 355 /* 356 * if we are writing, the copy the data into the page 357 */ 358 if ((bp->b_flags & B_READ) == 0) { 359 bcopy((caddr_t) va, (caddr_t) kva + (NBPG * i), NBPG); 360 } 361 } else { 362 /* 363 * use original page 364 */ 365 pmap_kenter(kva + (NBPG * i), pa); 366 } 367 va += NBPG; 368 } 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 */ 392 void 393 vm_bounce_free(bp) 394 struct buf *bp; 395 { 396 int i; 397 vm_offset_t origkva, bouncekva, bouncekvaend; 398 399 /* 400 * if this isn't a bounced buffer, then just return 401 */ 402 if ((bp->b_flags & B_BOUNCE) == 0) 403 return; 404 405 /* 406 * This check is not necessary 407 * if (bp->b_bufsize != bp->b_bcount) { 408 * printf("vm_bounce_free: b_bufsize=%d, b_bcount=%d\n", 409 * bp->b_bufsize, bp->b_bcount); 410 * } 411 */ 412 413 origkva = (vm_offset_t) bp->b_savekva; 414 bouncekva = (vm_offset_t) bp->b_data; 415 /* 416 printf("free: %d ", bp->b_bufsize); 417 */ 418 419 /* 420 * check every page in the kva space for b_addr 421 */ 422 for (i = 0; i < bp->b_bufsize; ) { 423 vm_offset_t mybouncepa; 424 vm_offset_t copycount; 425 426 copycount = i386_round_page(bouncekva + 1) - bouncekva; 427 mybouncepa = pmap_kextract(i386_trunc_page(bouncekva)); 428 429 /* 430 * if this is a bounced pa, then process as one 431 */ 432 if ( mybouncepa != pmap_kextract( i386_trunc_page( origkva))) { 433 vm_offset_t tocopy = copycount; 434 if (i + tocopy > bp->b_bufsize) 435 tocopy = bp->b_bufsize - i; 436 /* 437 * if this is a read, then copy from bounce buffer into original buffer 438 */ 439 if (bp->b_flags & B_READ) 440 bcopy((caddr_t) bouncekva, (caddr_t) origkva, tocopy); 441 /* 442 * free the bounce allocation 443 */ 444 445 /* 446 printf("(kva: %x, pa: %x)", bouncekva, mybouncepa); 447 */ 448 vm_bounce_page_free(mybouncepa, 1); 449 } 450 451 origkva += copycount; 452 bouncekva += copycount; 453 i += copycount; 454 } 455 456 /* 457 printf("\n"); 458 */ 459 /* 460 * add the old kva into the "to free" list 461 */ 462 463 bouncekva= i386_trunc_page((vm_offset_t) bp->b_data); 464 bouncekvaend= i386_round_page((vm_offset_t)bp->b_data + bp->b_bufsize); 465 466 /* 467 printf("freeva: %d\n", (bouncekvaend - bouncekva) / NBPG); 468 */ 469 vm_bounce_kva_free( bouncekva, (bouncekvaend - bouncekva), 0); 470 bp->b_data = bp->b_savekva; 471 bp->b_savekva = 0; 472 bp->b_flags &= ~B_BOUNCE; 473 474 return; 475 } 476 477 478 /* 479 * init the bounce buffer system 480 */ 481 void 482 vm_bounce_init() 483 { 484 int i; 485 486 kvasfreecnt = 0; 487 488 if (bouncepages == 0) 489 return; 490 491 bounceallocarraysize = (bouncepages + BITS_IN_UNSIGNED - 1) / BITS_IN_UNSIGNED; 492 bounceallocarray = malloc(bounceallocarraysize * sizeof(unsigned), M_TEMP, M_NOWAIT); 493 494 if (!bounceallocarray) 495 panic("Cannot allocate bounce resource array\n"); 496 497 bouncepa = malloc(bouncepages * sizeof(vm_offset_t), M_TEMP, M_NOWAIT); 498 if (!bouncepa) 499 panic("Cannot allocate physical memory array\n"); 500 501 for(i=0;i<bounceallocarraysize;i++) { 502 bounceallocarray[i] = 0xffffffff; 503 } 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 bounceallocarray[i/(8*sizeof(int))] &= ~(1<<(i%(8*sizeof(int)))); 513 } 514 bouncefree = bouncepages; 515 516 } 517 #endif /* BOUNCE_BUFFERS */ 518 /* 519 * quick version of vm_fault 520 */ 521 522 void 523 vm_fault_quick( v, prot) 524 vm_offset_t v; 525 int prot; 526 { 527 if( (cpu_class == CPUCLASS_386) && 528 (prot & VM_PROT_WRITE)) 529 vm_fault(&curproc->p_vmspace->vm_map, v, 530 VM_PROT_READ|VM_PROT_WRITE, FALSE); 531 else if( prot & VM_PROT_WRITE) 532 *(volatile char *)v += 0; 533 else 534 *(volatile char *)v; 535 } 536 537 538 /* 539 * Finish a fork operation, with process p2 nearly set up. 540 * Copy and update the kernel stack and pcb, making the child 541 * ready to run, and marking it so that it can return differently 542 * than the parent. Returns 1 in the child process, 0 in the parent. 543 * We currently double-map the user area so that the stack is at the same 544 * address in each process; in the future we will probably relocate 545 * the frame pointers on the stack after copying. 546 */ 547 int 548 cpu_fork(p1, p2) 549 register struct proc *p1, *p2; 550 { 551 register struct user *up = p2->p_addr; 552 int offset; 553 extern char kstack[]; 554 extern int mvesp(); 555 556 /* 557 * Copy pcb and stack from proc p1 to p2. 558 * We do this as cheaply as possible, copying only the active 559 * part of the stack. The stack and pcb need to agree; 560 * this is tricky, as the final pcb is constructed by savectx, 561 * but its frame isn't yet on the stack when the stack is copied. 562 * swtch compensates for this when the child eventually runs. 563 * This should be done differently, with a single call 564 * that copies and updates the pcb+stack, 565 * replacing the bcopy and savectx. 566 */ 567 p2->p_addr->u_pcb = p1->p_addr->u_pcb; 568 offset = mvesp() - (int)kstack; 569 bcopy((caddr_t)kstack + offset, (caddr_t)p2->p_addr + offset, 570 (unsigned) ctob(UPAGES) - offset); 571 p2->p_md.md_regs = p1->p_md.md_regs; 572 573 pmap_activate(&p2->p_vmspace->vm_pmap, &up->u_pcb); 574 575 /* 576 * 577 * Arrange for a non-local goto when the new process 578 * is started, to resume here, returning nonzero from setjmp. 579 */ 580 if (savectx(&up->u_pcb, 1)) { 581 /* 582 * Return 1 in child. 583 */ 584 return (1); 585 } 586 return (0); 587 } 588 589 void 590 cpu_exit(p) 591 register struct proc *p; 592 { 593 594 #if NNPX > 0 595 npxexit(p); 596 #endif /* NNPX */ 597 curproc = p; 598 mi_switch(); 599 /* 600 * This is to shutup the compiler, and if swtch() failed I suppose 601 * this would be a good thing. This keeps gcc happy because panic 602 * is a volatile void function as well. 603 */ 604 panic("cpu_exit"); 605 } 606 607 void 608 cpu_wait(p) struct proc *p; { 609 /* extern vm_map_t upages_map; */ 610 611 /* drop per-process resources */ 612 pmap_remove(vm_map_pmap(u_map), (vm_offset_t) p->p_addr, 613 ((vm_offset_t) p->p_addr) + ctob(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 */ 621 int 622 cpu_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 */ 636 void 637 setredzone(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 */ 656 657 void 658 pagemove(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_kremove((vm_offset_t)from); 673 pmap_kenter((vm_offset_t)to, pa); 674 from += PAGE_SIZE; 675 to += PAGE_SIZE; 676 size -= PAGE_SIZE; 677 } 678 } 679 680 /* 681 * Convert kernel VA to physical address 682 */ 683 u_long 684 kvtop(void *addr) 685 { 686 vm_offset_t va; 687 688 va = pmap_kextract((vm_offset_t)addr); 689 if (va == 0) 690 panic("kvtop: zero page frame"); 691 return((int)va); 692 } 693 694 /* 695 * Map an IO request into kernel virtual address space. 696 * 697 * All requests are (re)mapped into kernel VA space. 698 * Notice that we use b_bufsize for the size of the buffer 699 * to be mapped. b_bcount might be modified by the driver. 700 */ 701 void 702 vmapbuf(bp) 703 register struct buf *bp; 704 { 705 register int npf; 706 register caddr_t addr; 707 int off; 708 vm_offset_t kva; 709 vm_offset_t pa, lastv, v; 710 711 if ((bp->b_flags & B_PHYS) == 0) 712 panic("vmapbuf"); 713 714 /* 715 * this is the kva that is to be used for 716 * the temporary kernel mapping 717 */ 718 kva = (vm_offset_t) bp->b_saveaddr; 719 720 lastv = 0; 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 * make sure that the pde is valid and held 727 */ 728 v = trunc_page(((vm_offset_t)vtopte(addr))); 729 if (v != lastv) { 730 vm_fault_quick(v, VM_PROT_READ); 731 pa = pmap_kextract( v); 732 vm_page_hold(PHYS_TO_VM_PAGE(pa)); 733 lastv = v; 734 } 735 736 /* 737 * do the vm_fault if needed, do the copy-on-write thing when 738 * reading stuff off device into memory. 739 */ 740 vm_fault_quick(addr, 741 (bp->b_flags&B_READ)?(VM_PROT_READ|VM_PROT_WRITE):VM_PROT_READ); 742 pa = pmap_kextract((vm_offset_t) addr); 743 /* 744 * hold the data page 745 */ 746 vm_page_hold(PHYS_TO_VM_PAGE(pa)); 747 } 748 749 addr = bp->b_saveaddr = bp->b_data; 750 off = (int)addr & PGOFSET; 751 npf = btoc(round_page(bp->b_bufsize + off)); 752 bp->b_data = (caddr_t) (kva + off); 753 while (npf--) { 754 pa = pmap_kextract((vm_offset_t)addr); 755 if (pa == 0) 756 panic("vmapbuf: null page frame"); 757 pmap_kenter(kva, trunc_page(pa)); 758 addr += PAGE_SIZE; 759 kva += PAGE_SIZE; 760 } 761 } 762 763 /* 764 * Free the io map PTEs associated with this IO operation. 765 * We also invalidate the TLB entries and restore the original b_addr. 766 */ 767 void 768 vunmapbuf(bp) 769 register struct buf *bp; 770 { 771 register caddr_t addr; 772 vm_offset_t v,lastv,pa; 773 774 if ((bp->b_flags & B_PHYS) == 0) 775 panic("vunmapbuf"); 776 777 for (addr = (caddr_t)trunc_page((vm_offset_t) bp->b_data); 778 addr < bp->b_data + bp->b_bufsize; 779 addr += NBPG) 780 pmap_kremove((vm_offset_t) addr); 781 782 bp->b_data = bp->b_saveaddr; 783 bp->b_saveaddr = NULL; 784 785 /* 786 * unhold the pde, and data pages 787 */ 788 lastv = 0; 789 for (addr = (caddr_t)trunc_page((vm_offset_t) bp->b_data); 790 addr < bp->b_data + bp->b_bufsize; 791 addr += NBPG) { 792 793 /* 794 * release the data page 795 */ 796 pa = pmap_kextract((vm_offset_t) addr); 797 vm_page_unhold(PHYS_TO_VM_PAGE(pa)); 798 799 /* 800 * and unhold the page table 801 */ 802 v = trunc_page(((vm_offset_t)vtopte(addr))); 803 if (v != lastv) { 804 pa = pmap_kextract(v); 805 vm_page_unhold(PHYS_TO_VM_PAGE(pa)); 806 lastv = v; 807 } 808 } 809 } 810 811 /* 812 * Force reset the processor by invalidating the entire address space! 813 */ 814 void 815 cpu_reset() { 816 817 /* force a shutdown by unmapping entire address space ! */ 818 bzero((caddr_t) PTD, NBPG); 819 820 /* "good night, sweet prince .... <THUNK!>" */ 821 pmap_update(); 822 /* NOTREACHED */ 823 while(1); 824 } 825 826 /* 827 * Grow the user stack to allow for 'sp'. This version grows the stack in 828 * chunks of SGROWSIZ. 829 */ 830 int 831 grow(p, sp) 832 struct proc *p; 833 u_int sp; 834 { 835 unsigned int nss; 836 caddr_t v; 837 struct vmspace *vm = p->p_vmspace; 838 839 if ((caddr_t)sp <= vm->vm_maxsaddr || (unsigned)sp >= (unsigned)USRSTACK) 840 return (1); 841 842 nss = roundup(USRSTACK - (unsigned)sp, PAGE_SIZE); 843 844 if (nss > p->p_rlimit[RLIMIT_STACK].rlim_cur) 845 return (0); 846 847 if (vm->vm_ssize && roundup(vm->vm_ssize << PAGE_SHIFT, 848 SGROWSIZ) < nss) { 849 int grow_amount; 850 /* 851 * If necessary, grow the VM that the stack occupies 852 * to allow for the rlimit. This allows us to not have 853 * to allocate all of the VM up-front in execve (which 854 * is expensive). 855 * Grow the VM by the amount requested rounded up to 856 * the nearest SGROWSIZ to provide for some hysteresis. 857 */ 858 grow_amount = roundup((nss - (vm->vm_ssize << PAGE_SHIFT)), SGROWSIZ); 859 v = (char *)USRSTACK - roundup(vm->vm_ssize << PAGE_SHIFT, 860 SGROWSIZ) - grow_amount; 861 /* 862 * If there isn't enough room to extend by SGROWSIZ, then 863 * just extend to the maximum size 864 */ 865 if (v < vm->vm_maxsaddr) { 866 v = vm->vm_maxsaddr; 867 grow_amount = MAXSSIZ - (vm->vm_ssize << PAGE_SHIFT); 868 } 869 if (vm_allocate(&vm->vm_map, (vm_offset_t *)&v, 870 grow_amount, FALSE) != KERN_SUCCESS) { 871 return (0); 872 } 873 vm->vm_ssize += grow_amount >> PAGE_SHIFT; 874 } 875 876 return (1); 877 } 878