pmap.c revision 82310
1/* 2 * Copyright (c) 1991 Regents of the University of California. 3 * All rights reserved. 4 * Copyright (c) 1994 John S. Dyson 5 * All rights reserved. 6 * Copyright (c) 1994 David Greenman 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * the Systems Programming Group of the University of Utah Computer 11 * Science Department and William Jolitz of UUNET Technologies Inc. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 3. All advertising materials mentioning features or use of this software 22 * must display the following acknowledgement: 23 * This product includes software developed by the University of 24 * California, Berkeley and its contributors. 25 * 4. Neither the name of the University nor the names of its contributors 26 * may be used to endorse or promote products derived from this software 27 * without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 39 * SUCH DAMAGE. 40 * 41 * from: @(#)pmap.c 7.7 (Berkeley) 5/12/91 42 * $FreeBSD: head/sys/i386/i386/pmap.c 82310 2001-08-25 02:44:38Z julian $ 43 */ 44 45/* 46 * Manages physical address maps. 47 * 48 * In addition to hardware address maps, this 49 * module is called upon to provide software-use-only 50 * maps which may or may not be stored in the same 51 * form as hardware maps. These pseudo-maps are 52 * used to store intermediate results from copy 53 * operations to and from address spaces. 54 * 55 * Since the information managed by this module is 56 * also stored by the logical address mapping module, 57 * this module may throw away valid virtual-to-physical 58 * mappings at almost any time. However, invalidations 59 * of virtual-to-physical mappings must be done as 60 * requested. 61 * 62 * In order to cope with hardware architectures which 63 * make virtual-to-physical map invalidates expensive, 64 * this module may delay invalidate or reduced protection 65 * operations until such time as they are actually 66 * necessary. This module is given full information as 67 * to which processors are currently using which maps, 68 * and to when physical maps must be made correct. 69 */ 70 71#include "opt_disable_pse.h" 72#include "opt_pmap.h" 73#include "opt_msgbuf.h" 74#include "opt_upages.h" 75 76#include <sys/param.h> 77#include <sys/systm.h> 78#include <sys/kernel.h> 79#include <sys/lock.h> 80#include <sys/mman.h> 81#include <sys/msgbuf.h> 82#include <sys/mutex.h> 83#include <sys/proc.h> 84#include <sys/sx.h> 85#include <sys/user.h> 86#include <sys/vmmeter.h> 87#include <sys/sysctl.h> 88 89#include <vm/vm.h> 90#include <vm/vm_param.h> 91#include <vm/vm_kern.h> 92#include <vm/vm_page.h> 93#include <vm/vm_map.h> 94#include <vm/vm_object.h> 95#include <vm/vm_extern.h> 96#include <vm/vm_pageout.h> 97#include <vm/vm_pager.h> 98#include <vm/vm_zone.h> 99 100#include <machine/cputypes.h> 101#include <machine/md_var.h> 102#include <machine/specialreg.h> 103#if defined(SMP) || defined(APIC_IO) 104#include <machine/smp.h> 105#include <machine/apic.h> 106#include <machine/segments.h> 107#include <machine/tss.h> 108#include <machine/globaldata.h> 109#endif /* SMP || APIC_IO */ 110 111#define PMAP_KEEP_PDIRS 112#ifndef PMAP_SHPGPERPROC 113#define PMAP_SHPGPERPROC 200 114#endif 115 116#if defined(DIAGNOSTIC) 117#define PMAP_DIAGNOSTIC 118#endif 119 120#define MINPV 2048 121 122#if !defined(PMAP_DIAGNOSTIC) 123#define PMAP_INLINE __inline 124#else 125#define PMAP_INLINE 126#endif 127 128/* 129 * Get PDEs and PTEs for user/kernel address space 130 */ 131#define pmap_pde(m, v) (&((m)->pm_pdir[(vm_offset_t)(v) >> PDRSHIFT])) 132#define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT]) 133 134#define pmap_pde_v(pte) ((*(int *)pte & PG_V) != 0) 135#define pmap_pte_w(pte) ((*(int *)pte & PG_W) != 0) 136#define pmap_pte_m(pte) ((*(int *)pte & PG_M) != 0) 137#define pmap_pte_u(pte) ((*(int *)pte & PG_A) != 0) 138#define pmap_pte_v(pte) ((*(int *)pte & PG_V) != 0) 139 140#define pmap_pte_set_w(pte, v) ((v)?(*(int *)pte |= PG_W):(*(int *)pte &= ~PG_W)) 141#define pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v))) 142 143/* 144 * Given a map and a machine independent protection code, 145 * convert to a vax protection code. 146 */ 147#define pte_prot(m, p) (protection_codes[p]) 148static int protection_codes[8]; 149 150static struct pmap kernel_pmap_store; 151pmap_t kernel_pmap; 152LIST_HEAD(pmaplist, pmap); 153struct pmaplist allpmaps; 154 155vm_offset_t avail_start; /* PA of first available physical page */ 156vm_offset_t avail_end; /* PA of last available physical page */ 157vm_offset_t virtual_avail; /* VA of first avail page (after kernel bss) */ 158vm_offset_t virtual_end; /* VA of last avail page (end of kernel AS) */ 159static boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */ 160static int pgeflag; /* PG_G or-in */ 161static int pseflag; /* PG_PS or-in */ 162 163static vm_object_t kptobj; 164 165static int nkpt; 166vm_offset_t kernel_vm_end; 167 168/* 169 * Data for the pv entry allocation mechanism 170 */ 171static vm_zone_t pvzone; 172static struct vm_zone pvzone_store; 173static struct vm_object pvzone_obj; 174static int pv_entry_count=0, pv_entry_max=0, pv_entry_high_water=0; 175static int pmap_pagedaemon_waken = 0; 176static struct pv_entry *pvinit; 177 178/* 179 * All those kernel PT submaps that BSD is so fond of 180 */ 181pt_entry_t *CMAP1 = 0; 182static pt_entry_t *CMAP2, *ptmmap; 183caddr_t CADDR1 = 0, ptvmmap = 0; 184static caddr_t CADDR2; 185static pt_entry_t *msgbufmap; 186struct msgbuf *msgbufp=0; 187 188/* 189 * Crashdump maps. 190 */ 191static pt_entry_t *pt_crashdumpmap; 192static caddr_t crashdumpmap; 193 194#ifdef SMP 195extern pt_entry_t *SMPpt; 196#endif 197static pt_entry_t *PMAP1 = 0; 198static unsigned *PADDR1 = 0; 199 200static PMAP_INLINE void free_pv_entry __P((pv_entry_t pv)); 201static unsigned * get_ptbase __P((pmap_t pmap)); 202static pv_entry_t get_pv_entry __P((void)); 203static void i386_protection_init __P((void)); 204static __inline void pmap_changebit __P((vm_page_t m, int bit, boolean_t setem)); 205 206static void pmap_remove_all __P((vm_page_t m)); 207static vm_page_t pmap_enter_quick __P((pmap_t pmap, vm_offset_t va, 208 vm_page_t m, vm_page_t mpte)); 209static int pmap_remove_pte __P((struct pmap *pmap, unsigned *ptq, 210 vm_offset_t sva)); 211static void pmap_remove_page __P((struct pmap *pmap, vm_offset_t va)); 212static int pmap_remove_entry __P((struct pmap *pmap, vm_page_t m, 213 vm_offset_t va)); 214static boolean_t pmap_testbit __P((vm_page_t m, int bit)); 215static void pmap_insert_entry __P((pmap_t pmap, vm_offset_t va, 216 vm_page_t mpte, vm_page_t m)); 217 218static vm_page_t pmap_allocpte __P((pmap_t pmap, vm_offset_t va)); 219 220static int pmap_release_free_page __P((pmap_t pmap, vm_page_t p)); 221static vm_page_t _pmap_allocpte __P((pmap_t pmap, unsigned ptepindex)); 222static unsigned * pmap_pte_quick __P((pmap_t pmap, vm_offset_t va)); 223static vm_page_t pmap_page_lookup __P((vm_object_t object, vm_pindex_t pindex)); 224static int pmap_unuse_pt __P((pmap_t, vm_offset_t, vm_page_t)); 225static vm_offset_t pmap_kmem_choose(vm_offset_t addr); 226 227static unsigned pdir4mb; 228 229/* 230 * Routine: pmap_pte 231 * Function: 232 * Extract the page table entry associated 233 * with the given map/virtual_address pair. 234 */ 235 236PMAP_INLINE unsigned * 237pmap_pte(pmap, va) 238 register pmap_t pmap; 239 vm_offset_t va; 240{ 241 unsigned *pdeaddr; 242 243 if (pmap) { 244 pdeaddr = (unsigned *) pmap_pde(pmap, va); 245 if (*pdeaddr & PG_PS) 246 return pdeaddr; 247 if (*pdeaddr) { 248 return get_ptbase(pmap) + i386_btop(va); 249 } 250 } 251 return (0); 252} 253 254/* 255 * Move the kernel virtual free pointer to the next 256 * 4MB. This is used to help improve performance 257 * by using a large (4MB) page for much of the kernel 258 * (.text, .data, .bss) 259 */ 260static vm_offset_t 261pmap_kmem_choose(vm_offset_t addr) 262{ 263 vm_offset_t newaddr = addr; 264#ifndef DISABLE_PSE 265 if (cpu_feature & CPUID_PSE) { 266 newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 267 } 268#endif 269 return newaddr; 270} 271 272/* 273 * Bootstrap the system enough to run with virtual memory. 274 * 275 * On the i386 this is called after mapping has already been enabled 276 * and just syncs the pmap module with what has already been done. 277 * [We can't call it easily with mapping off since the kernel is not 278 * mapped with PA == VA, hence we would have to relocate every address 279 * from the linked base (virtual) address "KERNBASE" to the actual 280 * (physical) address starting relative to 0] 281 */ 282void 283pmap_bootstrap(firstaddr, loadaddr) 284 vm_offset_t firstaddr; 285 vm_offset_t loadaddr; 286{ 287 vm_offset_t va; 288 pt_entry_t *pte; 289 int i; 290 291 avail_start = firstaddr; 292 293 /* 294 * XXX The calculation of virtual_avail is wrong. It's NKPT*PAGE_SIZE too 295 * large. It should instead be correctly calculated in locore.s and 296 * not based on 'first' (which is a physical address, not a virtual 297 * address, for the start of unused physical memory). The kernel 298 * page tables are NOT double mapped and thus should not be included 299 * in this calculation. 300 */ 301 virtual_avail = (vm_offset_t) KERNBASE + firstaddr; 302 virtual_avail = pmap_kmem_choose(virtual_avail); 303 304 virtual_end = VM_MAX_KERNEL_ADDRESS; 305 306 /* 307 * Initialize protection array. 308 */ 309 i386_protection_init(); 310 311 /* 312 * The kernel's pmap is statically allocated so we don't have to use 313 * pmap_create, which is unlikely to work correctly at this part of 314 * the boot sequence (XXX and which no longer exists). 315 */ 316 kernel_pmap = &kernel_pmap_store; 317 318 kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD); 319 kernel_pmap->pm_count = 1; 320 kernel_pmap->pm_active = -1; /* don't allow deactivation */ 321 TAILQ_INIT(&kernel_pmap->pm_pvlist); 322 LIST_INIT(&allpmaps); 323 LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list); 324 nkpt = NKPT; 325 326 /* 327 * Reserve some special page table entries/VA space for temporary 328 * mapping of pages. 329 */ 330#define SYSMAP(c, p, v, n) \ 331 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n); 332 333 va = virtual_avail; 334 pte = (pt_entry_t *) pmap_pte(kernel_pmap, va); 335 336 /* 337 * CMAP1/CMAP2 are used for zeroing and copying pages. 338 */ 339 SYSMAP(caddr_t, CMAP1, CADDR1, 1) 340 SYSMAP(caddr_t, CMAP2, CADDR2, 1) 341 342 /* 343 * Crashdump maps. 344 */ 345 SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS); 346 347 /* 348 * ptvmmap is used for reading arbitrary physical pages via /dev/mem. 349 * XXX ptmmap is not used. 350 */ 351 SYSMAP(caddr_t, ptmmap, ptvmmap, 1) 352 353 /* 354 * msgbufp is used to map the system message buffer. 355 * XXX msgbufmap is not used. 356 */ 357 SYSMAP(struct msgbuf *, msgbufmap, msgbufp, 358 atop(round_page(MSGBUF_SIZE))) 359 360 /* 361 * ptemap is used for pmap_pte_quick 362 */ 363 SYSMAP(unsigned *, PMAP1, PADDR1, 1); 364 365 virtual_avail = va; 366 367 *(int *) CMAP1 = *(int *) CMAP2 = 0; 368 for (i = 0; i < NKPT; i++) 369 PTD[i] = 0; 370 371 pgeflag = 0; 372#if !defined(SMP) /* XXX - see also mp_machdep.c */ 373 if (cpu_feature & CPUID_PGE) { 374 pgeflag = PG_G; 375 } 376#endif 377 378/* 379 * Initialize the 4MB page size flag 380 */ 381 pseflag = 0; 382/* 383 * The 4MB page version of the initial 384 * kernel page mapping. 385 */ 386 pdir4mb = 0; 387 388#if !defined(DISABLE_PSE) 389 if (cpu_feature & CPUID_PSE) { 390 unsigned ptditmp; 391 /* 392 * Note that we have enabled PSE mode 393 */ 394 pseflag = PG_PS; 395 ptditmp = *((unsigned *)PTmap + i386_btop(KERNBASE)); 396 ptditmp &= ~(NBPDR - 1); 397 ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag; 398 pdir4mb = ptditmp; 399 400#if !defined(SMP) 401 /* 402 * Enable the PSE mode. 403 */ 404 load_cr4(rcr4() | CR4_PSE); 405 406 /* 407 * We can do the mapping here for the single processor 408 * case. We simply ignore the old page table page from 409 * now on. 410 */ 411 /* 412 * For SMP, we still need 4K pages to bootstrap APs, 413 * PSE will be enabled as soon as all APs are up. 414 */ 415 PTD[KPTDI] = (pd_entry_t) ptditmp; 416 kernel_pmap->pm_pdir[KPTDI] = (pd_entry_t) ptditmp; 417 invltlb(); 418#endif 419 } 420#endif 421 422#ifdef SMP 423 if (cpu_apic_address == 0) 424 panic("pmap_bootstrap: no local apic! (non-SMP hardware?)"); 425 426 /* local apic is mapped on last page */ 427 SMPpt[NPTEPG - 1] = (pt_entry_t)(PG_V | PG_RW | PG_N | pgeflag | 428 (cpu_apic_address & PG_FRAME)); 429#endif 430 431 invltlb(); 432} 433 434#ifdef SMP 435/* 436 * Set 4mb pdir for mp startup 437 */ 438void 439pmap_set_opt(void) 440{ 441 if (pseflag && (cpu_feature & CPUID_PSE)) { 442 load_cr4(rcr4() | CR4_PSE); 443 if (pdir4mb && PCPU_GET(cpuid) == 0) { /* only on BSP */ 444 kernel_pmap->pm_pdir[KPTDI] = 445 PTD[KPTDI] = (pd_entry_t)pdir4mb; 446 cpu_invltlb(); 447 } 448 } 449} 450#endif 451 452/* 453 * Initialize the pmap module. 454 * Called by vm_init, to initialize any structures that the pmap 455 * system needs to map virtual memory. 456 * pmap_init has been enhanced to support in a fairly consistant 457 * way, discontiguous physical memory. 458 */ 459void 460pmap_init(phys_start, phys_end) 461 vm_offset_t phys_start, phys_end; 462{ 463 int i; 464 int initial_pvs; 465 466 /* 467 * object for kernel page table pages 468 */ 469 kptobj = vm_object_allocate(OBJT_DEFAULT, NKPDE); 470 471 /* 472 * Allocate memory for random pmap data structures. Includes the 473 * pv_head_table. 474 */ 475 476 for(i = 0; i < vm_page_array_size; i++) { 477 vm_page_t m; 478 479 m = &vm_page_array[i]; 480 TAILQ_INIT(&m->md.pv_list); 481 m->md.pv_list_count = 0; 482 } 483 484 /* 485 * init the pv free list 486 */ 487 initial_pvs = vm_page_array_size; 488 if (initial_pvs < MINPV) 489 initial_pvs = MINPV; 490 pvzone = &pvzone_store; 491 pvinit = (struct pv_entry *) kmem_alloc(kernel_map, 492 initial_pvs * sizeof (struct pv_entry)); 493 zbootinit(pvzone, "PV ENTRY", sizeof (struct pv_entry), pvinit, 494 vm_page_array_size); 495 496 /* 497 * Now it is safe to enable pv_table recording. 498 */ 499 pmap_initialized = TRUE; 500} 501 502/* 503 * Initialize the address space (zone) for the pv_entries. Set a 504 * high water mark so that the system can recover from excessive 505 * numbers of pv entries. 506 */ 507void 508pmap_init2() 509{ 510 int shpgperproc = PMAP_SHPGPERPROC; 511 512 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc); 513 pv_entry_max = shpgperproc * maxproc + vm_page_array_size; 514 pv_entry_high_water = 9 * (pv_entry_max / 10); 515 zinitna(pvzone, &pvzone_obj, NULL, 0, pv_entry_max, ZONE_INTERRUPT, 1); 516} 517 518 519/*************************************************** 520 * Low level helper routines..... 521 ***************************************************/ 522 523#if defined(PMAP_DIAGNOSTIC) 524 525/* 526 * This code checks for non-writeable/modified pages. 527 * This should be an invalid condition. 528 */ 529static int 530pmap_nw_modified(pt_entry_t ptea) 531{ 532 int pte; 533 534 pte = (int) ptea; 535 536 if ((pte & (PG_M|PG_RW)) == PG_M) 537 return 1; 538 else 539 return 0; 540} 541#endif 542 543 544/* 545 * this routine defines the region(s) of memory that should 546 * not be tested for the modified bit. 547 */ 548static PMAP_INLINE int 549pmap_track_modified(vm_offset_t va) 550{ 551 if ((va < kmi.clean_sva) || (va >= kmi.clean_eva)) 552 return 1; 553 else 554 return 0; 555} 556 557static PMAP_INLINE void 558invltlb_1pg(vm_offset_t va) 559{ 560#ifdef I386_CPU 561 invltlb(); 562#else 563 invlpg(va); 564#endif 565} 566 567static __inline void 568pmap_TLB_invalidate(pmap_t pmap, vm_offset_t va) 569{ 570#if defined(SMP) 571 if (pmap->pm_active & (1 << PCPU_GET(cpuid))) 572 cpu_invlpg((void *)va); 573 if (pmap->pm_active & PCPU_GET(other_cpus)) 574 smp_invltlb(); 575#else 576 if (pmap->pm_active) 577 invltlb_1pg(va); 578#endif 579} 580 581static __inline void 582pmap_TLB_invalidate_all(pmap_t pmap) 583{ 584#if defined(SMP) 585 if (pmap->pm_active & (1 << PCPU_GET(cpuid))) 586 cpu_invltlb(); 587 if (pmap->pm_active & PCPU_GET(other_cpus)) 588 smp_invltlb(); 589#else 590 if (pmap->pm_active) 591 invltlb(); 592#endif 593} 594 595/* 596 * Return an address which is the base of the Virtual mapping of 597 * all the PTEs for the given pmap. Note this doesn't say that 598 * all the PTEs will be present or that the pages there are valid. 599 * The PTEs are made available by the recursive mapping trick. 600 * It will map in the alternate PTE space if needed. 601 */ 602static unsigned * 603get_ptbase(pmap) 604 pmap_t pmap; 605{ 606 unsigned frame = (unsigned) pmap->pm_pdir[PTDPTDI] & PG_FRAME; 607 608 /* are we current address space or kernel? */ 609 if (pmap == kernel_pmap || frame == (((unsigned) PTDpde) & PG_FRAME)) { 610 return (unsigned *) PTmap; 611 } 612 /* otherwise, we are alternate address space */ 613 if (frame != (((unsigned) APTDpde) & PG_FRAME)) { 614 APTDpde = (pd_entry_t) (frame | PG_RW | PG_V); 615#if defined(SMP) 616 /* The page directory is not shared between CPUs */ 617 cpu_invltlb(); 618#else 619 invltlb(); 620#endif 621 } 622 return (unsigned *) APTmap; 623} 624 625/* 626 * Super fast pmap_pte routine best used when scanning 627 * the pv lists. This eliminates many coarse-grained 628 * invltlb calls. Note that many of the pv list 629 * scans are across different pmaps. It is very wasteful 630 * to do an entire invltlb for checking a single mapping. 631 */ 632 633static unsigned * 634pmap_pte_quick(pmap, va) 635 register pmap_t pmap; 636 vm_offset_t va; 637{ 638 unsigned pde, newpf; 639 if ((pde = (unsigned) pmap->pm_pdir[va >> PDRSHIFT]) != 0) { 640 unsigned frame = (unsigned) pmap->pm_pdir[PTDPTDI] & PG_FRAME; 641 unsigned index = i386_btop(va); 642 /* are we current address space or kernel? */ 643 if ((pmap == kernel_pmap) || 644 (frame == (((unsigned) PTDpde) & PG_FRAME))) { 645 return (unsigned *) PTmap + index; 646 } 647 newpf = pde & PG_FRAME; 648 if ( ((* (unsigned *) PMAP1) & PG_FRAME) != newpf) { 649 * (unsigned *) PMAP1 = newpf | PG_RW | PG_V; 650 invltlb_1pg((vm_offset_t) PADDR1); 651 } 652 return PADDR1 + ((unsigned) index & (NPTEPG - 1)); 653 } 654 return (0); 655} 656 657/* 658 * Routine: pmap_extract 659 * Function: 660 * Extract the physical page address associated 661 * with the given map/virtual_address pair. 662 */ 663vm_offset_t 664pmap_extract(pmap, va) 665 register pmap_t pmap; 666 vm_offset_t va; 667{ 668 vm_offset_t rtval; 669 vm_offset_t pdirindex; 670 pdirindex = va >> PDRSHIFT; 671 if (pmap && (rtval = (unsigned) pmap->pm_pdir[pdirindex])) { 672 unsigned *pte; 673 if ((rtval & PG_PS) != 0) { 674 rtval &= ~(NBPDR - 1); 675 rtval |= va & (NBPDR - 1); 676 return rtval; 677 } 678 pte = get_ptbase(pmap) + i386_btop(va); 679 rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); 680 return rtval; 681 } 682 return 0; 683 684} 685 686/*************************************************** 687 * Low level mapping routines..... 688 ***************************************************/ 689 690/* 691 * add a wired page to the kva 692 * note that in order for the mapping to take effect -- you 693 * should do a invltlb after doing the pmap_kenter... 694 */ 695PMAP_INLINE void 696pmap_kenter(va, pa) 697 vm_offset_t va; 698 register vm_offset_t pa; 699{ 700 register unsigned *pte; 701 unsigned npte, opte; 702 703 npte = pa | PG_RW | PG_V | pgeflag; 704 pte = (unsigned *)vtopte(va); 705 opte = *pte; 706 *pte = npte; 707 /*if (opte)*/ 708 invltlb_1pg(va); /* XXX what about SMP? */ 709} 710 711/* 712 * remove a page from the kernel pagetables 713 */ 714PMAP_INLINE void 715pmap_kremove(va) 716 vm_offset_t va; 717{ 718 register unsigned *pte; 719 720 pte = (unsigned *)vtopte(va); 721 *pte = 0; 722 invltlb_1pg(va); /* XXX what about SMP? */ 723} 724 725/* 726 * Used to map a range of physical addresses into kernel 727 * virtual address space. 728 * 729 * The value passed in '*virt' is a suggested virtual address for 730 * the mapping. Architectures which can support a direct-mapped 731 * physical to virtual region can return the appropriate address 732 * within that region, leaving '*virt' unchanged. Other 733 * architectures should map the pages starting at '*virt' and 734 * update '*virt' with the first usable address after the mapped 735 * region. 736 */ 737vm_offset_t 738pmap_map(virt, start, end, prot) 739 vm_offset_t *virt; 740 vm_offset_t start; 741 vm_offset_t end; 742 int prot; 743{ 744 vm_offset_t sva = *virt; 745 vm_offset_t va = sva; 746 while (start < end) { 747 pmap_kenter(va, start); 748 va += PAGE_SIZE; 749 start += PAGE_SIZE; 750 } 751 *virt = va; 752 return (sva); 753} 754 755 756/* 757 * Add a list of wired pages to the kva 758 * this routine is only used for temporary 759 * kernel mappings that do not need to have 760 * page modification or references recorded. 761 * Note that old mappings are simply written 762 * over. The page *must* be wired. 763 */ 764void 765pmap_qenter(va, m, count) 766 vm_offset_t va; 767 vm_page_t *m; 768 int count; 769{ 770 int i; 771 772 for (i = 0; i < count; i++) { 773 vm_offset_t tva = va + i * PAGE_SIZE; 774 pmap_kenter(tva, VM_PAGE_TO_PHYS(m[i])); 775 } 776} 777 778/* 779 * this routine jerks page mappings from the 780 * kernel -- it is meant only for temporary mappings. 781 */ 782void 783pmap_qremove(va, count) 784 vm_offset_t va; 785 int count; 786{ 787 vm_offset_t end_va; 788 789 end_va = va + count*PAGE_SIZE; 790 791 while (va < end_va) { 792 unsigned *pte; 793 794 pte = (unsigned *)vtopte(va); 795 *pte = 0; 796#ifdef SMP 797 cpu_invlpg((void *)va); 798#else 799 invltlb_1pg(va); 800#endif 801 va += PAGE_SIZE; 802 } 803#ifdef SMP 804 smp_invltlb(); 805#endif 806} 807 808static vm_page_t 809pmap_page_lookup(object, pindex) 810 vm_object_t object; 811 vm_pindex_t pindex; 812{ 813 vm_page_t m; 814retry: 815 m = vm_page_lookup(object, pindex); 816 if (m && vm_page_sleep_busy(m, FALSE, "pplookp")) 817 goto retry; 818 return m; 819} 820 821/* 822 * Create the UPAGES for a new process. 823 * This routine directly affects the fork perf for a process. 824 */ 825void 826pmap_new_proc(p) 827 struct proc *p; 828{ 829#ifdef I386_CPU 830 int updateneeded; 831#endif 832 int i; 833 vm_object_t upobj; 834 vm_page_t m; 835 struct user *up; 836 unsigned *ptek, oldpte; 837 838 /* 839 * allocate object for the upages 840 */ 841 if ((upobj = p->p_upages_obj) == NULL) { 842 upobj = vm_object_allocate( OBJT_DEFAULT, UPAGES); 843 p->p_upages_obj = upobj; 844 } 845 846 /* get a kernel virtual address for the UPAGES for this proc */ 847 if ((up = p->p_addr) == NULL) { 848 up = (struct user *) kmem_alloc_nofault(kernel_map, 849 UPAGES * PAGE_SIZE); 850 if (up == NULL) 851 panic("pmap_new_proc: u_map allocation failed"); 852 p->p_addr = up; 853 } 854 855 ptek = (unsigned *) vtopte((vm_offset_t) up); 856 857#ifdef I386_CPU 858 updateneeded = 0; 859#endif 860 for(i=0;i<UPAGES;i++) { 861 /* 862 * Get a kernel stack page 863 */ 864 m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 865 866 /* 867 * Wire the page 868 */ 869 m->wire_count++; 870 cnt.v_wire_count++; 871 872 oldpte = *(ptek + i); 873 /* 874 * Enter the page into the kernel address space. 875 */ 876 *(ptek + i) = VM_PAGE_TO_PHYS(m) | PG_RW | PG_V | pgeflag; 877 if (oldpte) { 878#ifdef I386_CPU 879 updateneeded = 1; 880#else 881 invlpg((vm_offset_t) up + i * PAGE_SIZE); 882#endif 883 } 884 885 vm_page_wakeup(m); 886 vm_page_flag_clear(m, PG_ZERO); 887 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 888 m->valid = VM_PAGE_BITS_ALL; 889 } 890#ifdef I386_CPU 891 if (updateneeded) 892 invltlb(); 893#endif 894} 895 896/* 897 * Dispose the UPAGES for a process that has exited. 898 * This routine directly impacts the exit perf of a process. 899 */ 900void 901pmap_dispose_proc(p) 902 struct proc *p; 903{ 904 int i; 905 vm_object_t upobj; 906 vm_page_t m; 907 unsigned *ptek, oldpte; 908 909 upobj = p->p_upages_obj; 910 911 ptek = (unsigned *) vtopte((vm_offset_t) p->p_addr); 912 for(i=0;i<UPAGES;i++) { 913 914 if ((m = vm_page_lookup(upobj, i)) == NULL) 915 panic("pmap_dispose_proc: upage already missing???"); 916 917 vm_page_busy(m); 918 919 oldpte = *(ptek + i); 920 *(ptek + i) = 0; 921#ifndef I386_CPU 922 invlpg((vm_offset_t) p->p_addr + i * PAGE_SIZE); 923#endif 924 vm_page_unwire(m, 0); 925 vm_page_free(m); 926 } 927#ifdef I386_CPU 928 invltlb(); 929#endif 930} 931 932/* 933 * Allow the UPAGES for a process to be prejudicially paged out. 934 */ 935void 936pmap_swapout_proc(p) 937 struct proc *p; 938{ 939 int i; 940 vm_object_t upobj; 941 vm_page_t m; 942 943 upobj = p->p_upages_obj; 944 /* 945 * let the upages be paged 946 */ 947 for(i=0;i<UPAGES;i++) { 948 if ((m = vm_page_lookup(upobj, i)) == NULL) 949 panic("pmap_swapout_proc: upage already missing???"); 950 vm_page_dirty(m); 951 vm_page_unwire(m, 0); 952 pmap_kremove( (vm_offset_t) p->p_addr + PAGE_SIZE * i); 953 } 954} 955 956/* 957 * Bring the UPAGES for a specified process back in. 958 */ 959void 960pmap_swapin_proc(p) 961 struct proc *p; 962{ 963 int i,rv; 964 vm_object_t upobj; 965 vm_page_t m; 966 967 upobj = p->p_upages_obj; 968 for(i=0;i<UPAGES;i++) { 969 970 m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 971 972 pmap_kenter(((vm_offset_t) p->p_addr) + i * PAGE_SIZE, 973 VM_PAGE_TO_PHYS(m)); 974 975 if (m->valid != VM_PAGE_BITS_ALL) { 976 rv = vm_pager_get_pages(upobj, &m, 1, 0); 977 if (rv != VM_PAGER_OK) 978 panic("pmap_swapin_proc: cannot get upages for proc: %d\n", p->p_pid); 979 m = vm_page_lookup(upobj, i); 980 m->valid = VM_PAGE_BITS_ALL; 981 } 982 983 vm_page_wire(m); 984 vm_page_wakeup(m); 985 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 986 } 987} 988 989/*************************************************** 990 * Page table page management routines..... 991 ***************************************************/ 992 993/* 994 * This routine unholds page table pages, and if the hold count 995 * drops to zero, then it decrements the wire count. 996 */ 997static int 998_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) { 999 1000 while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) 1001 ; 1002 1003 if (m->hold_count == 0) { 1004 vm_offset_t pteva; 1005 /* 1006 * unmap the page table page 1007 */ 1008 pmap->pm_pdir[m->pindex] = 0; 1009 --pmap->pm_stats.resident_count; 1010 if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) == 1011 (((unsigned) PTDpde) & PG_FRAME)) { 1012 /* 1013 * Do a invltlb to make the invalidated mapping 1014 * take effect immediately. 1015 */ 1016 pteva = UPT_MIN_ADDRESS + i386_ptob(m->pindex); 1017 pmap_TLB_invalidate(pmap, pteva); 1018 } 1019 1020 if (pmap->pm_ptphint == m) 1021 pmap->pm_ptphint = NULL; 1022 1023 /* 1024 * If the page is finally unwired, simply free it. 1025 */ 1026 --m->wire_count; 1027 if (m->wire_count == 0) { 1028 1029 vm_page_flash(m); 1030 vm_page_busy(m); 1031 vm_page_free_zero(m); 1032 --cnt.v_wire_count; 1033 } 1034 return 1; 1035 } 1036 return 0; 1037} 1038 1039static PMAP_INLINE int 1040pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1041{ 1042 vm_page_unhold(m); 1043 if (m->hold_count == 0) 1044 return _pmap_unwire_pte_hold(pmap, m); 1045 else 1046 return 0; 1047} 1048 1049/* 1050 * After removing a page table entry, this routine is used to 1051 * conditionally free the page, and manage the hold/wire counts. 1052 */ 1053static int 1054pmap_unuse_pt(pmap, va, mpte) 1055 pmap_t pmap; 1056 vm_offset_t va; 1057 vm_page_t mpte; 1058{ 1059 unsigned ptepindex; 1060 if (va >= UPT_MIN_ADDRESS) 1061 return 0; 1062 1063 if (mpte == NULL) { 1064 ptepindex = (va >> PDRSHIFT); 1065 if (pmap->pm_ptphint && 1066 (pmap->pm_ptphint->pindex == ptepindex)) { 1067 mpte = pmap->pm_ptphint; 1068 } else { 1069 mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex); 1070 pmap->pm_ptphint = mpte; 1071 } 1072 } 1073 1074 return pmap_unwire_pte_hold(pmap, mpte); 1075} 1076 1077void 1078pmap_pinit0(pmap) 1079 struct pmap *pmap; 1080{ 1081 pmap->pm_pdir = 1082 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1083 pmap_kenter((vm_offset_t) pmap->pm_pdir, (vm_offset_t) IdlePTD); 1084 pmap->pm_count = 1; 1085 pmap->pm_active = 0; 1086 pmap->pm_ptphint = NULL; 1087 TAILQ_INIT(&pmap->pm_pvlist); 1088 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1089 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1090} 1091 1092/* 1093 * Initialize a preallocated and zeroed pmap structure, 1094 * such as one in a vmspace structure. 1095 */ 1096void 1097pmap_pinit(pmap) 1098 register struct pmap *pmap; 1099{ 1100 vm_page_t ptdpg; 1101 1102 /* 1103 * No need to allocate page table space yet but we do need a valid 1104 * page directory table. 1105 */ 1106 if (pmap->pm_pdir == NULL) 1107 pmap->pm_pdir = 1108 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1109 1110 /* 1111 * allocate object for the ptes 1112 */ 1113 if (pmap->pm_pteobj == NULL) 1114 pmap->pm_pteobj = vm_object_allocate( OBJT_DEFAULT, PTDPTDI + 1); 1115 1116 /* 1117 * allocate the page directory page 1118 */ 1119 ptdpg = vm_page_grab( pmap->pm_pteobj, PTDPTDI, 1120 VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1121 1122 ptdpg->wire_count = 1; 1123 ++cnt.v_wire_count; 1124 1125 1126 vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/ 1127 ptdpg->valid = VM_PAGE_BITS_ALL; 1128 1129 pmap_kenter((vm_offset_t) pmap->pm_pdir, VM_PAGE_TO_PHYS(ptdpg)); 1130 if ((ptdpg->flags & PG_ZERO) == 0) 1131 bzero(pmap->pm_pdir, PAGE_SIZE); 1132 1133 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1134 /* Wire in kernel global address entries. */ 1135 /* XXX copies current process, does not fill in MPPTDI */ 1136 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1137#ifdef SMP 1138 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1139#endif 1140 1141 /* install self-referential address mapping entry */ 1142 *(unsigned *) (pmap->pm_pdir + PTDPTDI) = 1143 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1144 1145 pmap->pm_count = 1; 1146 pmap->pm_active = 0; 1147 pmap->pm_ptphint = NULL; 1148 TAILQ_INIT(&pmap->pm_pvlist); 1149 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1150} 1151 1152/* 1153 * Wire in kernel global address entries. To avoid a race condition 1154 * between pmap initialization and pmap_growkernel, this procedure 1155 * should be called after the vmspace is attached to the process 1156 * but before this pmap is activated. 1157 */ 1158void 1159pmap_pinit2(pmap) 1160 struct pmap *pmap; 1161{ 1162 /* XXX: Remove this stub when no longer called */ 1163} 1164 1165static int 1166pmap_release_free_page(pmap, p) 1167 struct pmap *pmap; 1168 vm_page_t p; 1169{ 1170 unsigned *pde = (unsigned *) pmap->pm_pdir; 1171 /* 1172 * This code optimizes the case of freeing non-busy 1173 * page-table pages. Those pages are zero now, and 1174 * might as well be placed directly into the zero queue. 1175 */ 1176 if (vm_page_sleep_busy(p, FALSE, "pmaprl")) 1177 return 0; 1178 1179 vm_page_busy(p); 1180 1181 /* 1182 * Remove the page table page from the processes address space. 1183 */ 1184 pde[p->pindex] = 0; 1185 pmap->pm_stats.resident_count--; 1186 1187 if (p->hold_count) { 1188 panic("pmap_release: freeing held page table page"); 1189 } 1190 /* 1191 * Page directory pages need to have the kernel 1192 * stuff cleared, so they can go into the zero queue also. 1193 */ 1194 if (p->pindex == PTDPTDI) { 1195 bzero(pde + KPTDI, nkpt * PTESIZE); 1196#ifdef SMP 1197 pde[MPPTDI] = 0; 1198#endif 1199 pde[APTDPTDI] = 0; 1200 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1201 } 1202 1203 if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex)) 1204 pmap->pm_ptphint = NULL; 1205 1206 p->wire_count--; 1207 cnt.v_wire_count--; 1208 vm_page_free_zero(p); 1209 return 1; 1210} 1211 1212/* 1213 * this routine is called if the page table page is not 1214 * mapped correctly. 1215 */ 1216static vm_page_t 1217_pmap_allocpte(pmap, ptepindex) 1218 pmap_t pmap; 1219 unsigned ptepindex; 1220{ 1221 vm_offset_t pteva, ptepa; 1222 vm_page_t m; 1223 1224 /* 1225 * Find or fabricate a new pagetable page 1226 */ 1227 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1228 VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1229 1230 KASSERT(m->queue == PQ_NONE, 1231 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1232 1233 if (m->wire_count == 0) 1234 cnt.v_wire_count++; 1235 m->wire_count++; 1236 1237 /* 1238 * Increment the hold count for the page table page 1239 * (denoting a new mapping.) 1240 */ 1241 m->hold_count++; 1242 1243 /* 1244 * Map the pagetable page into the process address space, if 1245 * it isn't already there. 1246 */ 1247 1248 pmap->pm_stats.resident_count++; 1249 1250 ptepa = VM_PAGE_TO_PHYS(m); 1251 pmap->pm_pdir[ptepindex] = 1252 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1253 1254 /* 1255 * Set the page table hint 1256 */ 1257 pmap->pm_ptphint = m; 1258 1259 /* 1260 * Try to use the new mapping, but if we cannot, then 1261 * do it with the routine that maps the page explicitly. 1262 */ 1263 if ((m->flags & PG_ZERO) == 0) { 1264 if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) == 1265 (((unsigned) PTDpde) & PG_FRAME)) { 1266 pteva = UPT_MIN_ADDRESS + i386_ptob(ptepindex); 1267 bzero((caddr_t) pteva, PAGE_SIZE); 1268 } else { 1269 pmap_zero_page(ptepa); 1270 } 1271 } 1272 1273 m->valid = VM_PAGE_BITS_ALL; 1274 vm_page_flag_clear(m, PG_ZERO); 1275 vm_page_flag_set(m, PG_MAPPED); 1276 vm_page_wakeup(m); 1277 1278 return m; 1279} 1280 1281static vm_page_t 1282pmap_allocpte(pmap, va) 1283 pmap_t pmap; 1284 vm_offset_t va; 1285{ 1286 unsigned ptepindex; 1287 vm_offset_t ptepa; 1288 vm_page_t m; 1289 1290 /* 1291 * Calculate pagetable page index 1292 */ 1293 ptepindex = va >> PDRSHIFT; 1294 1295 /* 1296 * Get the page directory entry 1297 */ 1298 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1299 1300 /* 1301 * This supports switching from a 4MB page to a 1302 * normal 4K page. 1303 */ 1304 if (ptepa & PG_PS) { 1305 pmap->pm_pdir[ptepindex] = 0; 1306 ptepa = 0; 1307 invltlb(); 1308 } 1309 1310 /* 1311 * If the page table page is mapped, we just increment the 1312 * hold count, and activate it. 1313 */ 1314 if (ptepa) { 1315 /* 1316 * In order to get the page table page, try the 1317 * hint first. 1318 */ 1319 if (pmap->pm_ptphint && 1320 (pmap->pm_ptphint->pindex == ptepindex)) { 1321 m = pmap->pm_ptphint; 1322 } else { 1323 m = pmap_page_lookup( pmap->pm_pteobj, ptepindex); 1324 pmap->pm_ptphint = m; 1325 } 1326 m->hold_count++; 1327 return m; 1328 } 1329 /* 1330 * Here if the pte page isn't mapped, or if it has been deallocated. 1331 */ 1332 return _pmap_allocpte(pmap, ptepindex); 1333} 1334 1335 1336/*************************************************** 1337* Pmap allocation/deallocation routines. 1338 ***************************************************/ 1339 1340/* 1341 * Release any resources held by the given physical map. 1342 * Called when a pmap initialized by pmap_pinit is being released. 1343 * Should only be called if the map contains no valid mappings. 1344 */ 1345void 1346pmap_release(pmap) 1347 register struct pmap *pmap; 1348{ 1349 vm_page_t p,n,ptdpg; 1350 vm_object_t object = pmap->pm_pteobj; 1351 int curgeneration; 1352 1353#if defined(DIAGNOSTIC) 1354 if (object->ref_count != 1) 1355 panic("pmap_release: pteobj reference count != 1"); 1356#endif 1357 1358 ptdpg = NULL; 1359 LIST_REMOVE(pmap, pm_list); 1360retry: 1361 curgeneration = object->generation; 1362 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1363 n = TAILQ_NEXT(p, listq); 1364 if (p->pindex == PTDPTDI) { 1365 ptdpg = p; 1366 continue; 1367 } 1368 while (1) { 1369 if (!pmap_release_free_page(pmap, p) && 1370 (object->generation != curgeneration)) 1371 goto retry; 1372 } 1373 } 1374 1375 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1376 goto retry; 1377} 1378 1379static int 1380kvm_size(SYSCTL_HANDLER_ARGS) 1381{ 1382 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1383 1384 return sysctl_handle_long(oidp, &ksize, 0, req); 1385} 1386SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1387 0, 0, kvm_size, "IU", "Size of KVM"); 1388 1389static int 1390kvm_free(SYSCTL_HANDLER_ARGS) 1391{ 1392 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1393 1394 return sysctl_handle_long(oidp, &kfree, 0, req); 1395} 1396SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1397 0, 0, kvm_free, "IU", "Amount of KVM free"); 1398 1399/* 1400 * grow the number of kernel page table entries, if needed 1401 */ 1402void 1403pmap_growkernel(vm_offset_t addr) 1404{ 1405 struct pmap *pmap; 1406 int s; 1407 vm_offset_t ptppaddr; 1408 vm_page_t nkpg; 1409 pd_entry_t newpdir; 1410 1411 s = splhigh(); 1412 if (kernel_vm_end == 0) { 1413 kernel_vm_end = KERNBASE; 1414 nkpt = 0; 1415 while (pdir_pde(PTD, kernel_vm_end)) { 1416 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1417 nkpt++; 1418 } 1419 } 1420 addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1421 while (kernel_vm_end < addr) { 1422 if (pdir_pde(PTD, kernel_vm_end)) { 1423 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1424 continue; 1425 } 1426 1427 /* 1428 * This index is bogus, but out of the way 1429 */ 1430 nkpg = vm_page_alloc(kptobj, nkpt, VM_ALLOC_SYSTEM); 1431 if (!nkpg) 1432 panic("pmap_growkernel: no memory to grow kernel"); 1433 1434 nkpt++; 1435 1436 vm_page_wire(nkpg); 1437 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1438 pmap_zero_page(ptppaddr); 1439 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1440 pdir_pde(PTD, kernel_vm_end) = newpdir; 1441 1442 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1443 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1444 } 1445 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1446 } 1447 splx(s); 1448} 1449 1450/* 1451 * Retire the given physical map from service. 1452 * Should only be called if the map contains 1453 * no valid mappings. 1454 */ 1455void 1456pmap_destroy(pmap) 1457 register pmap_t pmap; 1458{ 1459 int count; 1460 1461 if (pmap == NULL) 1462 return; 1463 1464 count = --pmap->pm_count; 1465 if (count == 0) { 1466 pmap_release(pmap); 1467 panic("destroying a pmap is not yet implemented"); 1468 } 1469} 1470 1471/* 1472 * Add a reference to the specified pmap. 1473 */ 1474void 1475pmap_reference(pmap) 1476 pmap_t pmap; 1477{ 1478 if (pmap != NULL) { 1479 pmap->pm_count++; 1480 } 1481} 1482 1483/*************************************************** 1484* page management routines. 1485 ***************************************************/ 1486 1487/* 1488 * free the pv_entry back to the free list 1489 */ 1490static PMAP_INLINE void 1491free_pv_entry(pv) 1492 pv_entry_t pv; 1493{ 1494 pv_entry_count--; 1495 zfree(pvzone, pv); 1496} 1497 1498/* 1499 * get a new pv_entry, allocating a block from the system 1500 * when needed. 1501 * the memory allocation is performed bypassing the malloc code 1502 * because of the possibility of allocations at interrupt time. 1503 */ 1504static pv_entry_t 1505get_pv_entry(void) 1506{ 1507 pv_entry_count++; 1508 if (pv_entry_high_water && 1509 (pv_entry_count > pv_entry_high_water) && 1510 (pmap_pagedaemon_waken == 0)) { 1511 pmap_pagedaemon_waken = 1; 1512 wakeup (&vm_pages_needed); 1513 } 1514 return zalloc(pvzone); 1515} 1516 1517/* 1518 * This routine is very drastic, but can save the system 1519 * in a pinch. 1520 */ 1521void 1522pmap_collect() 1523{ 1524 int i; 1525 vm_page_t m; 1526 static int warningdone=0; 1527 1528 if (pmap_pagedaemon_waken == 0) 1529 return; 1530 1531 if (warningdone < 5) { 1532 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1533 warningdone++; 1534 } 1535 1536 for(i = 0; i < vm_page_array_size; i++) { 1537 m = &vm_page_array[i]; 1538 if (m->wire_count || m->hold_count || m->busy || 1539 (m->flags & PG_BUSY)) 1540 continue; 1541 pmap_remove_all(m); 1542 } 1543 pmap_pagedaemon_waken = 0; 1544} 1545 1546 1547/* 1548 * If it is the first entry on the list, it is actually 1549 * in the header and we must copy the following entry up 1550 * to the header. Otherwise we must search the list for 1551 * the entry. In either case we free the now unused entry. 1552 */ 1553 1554static int 1555pmap_remove_entry(pmap, m, va) 1556 struct pmap *pmap; 1557 vm_page_t m; 1558 vm_offset_t va; 1559{ 1560 pv_entry_t pv; 1561 int rtval; 1562 int s; 1563 1564 s = splvm(); 1565 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1566 for (pv = TAILQ_FIRST(&m->md.pv_list); 1567 pv; 1568 pv = TAILQ_NEXT(pv, pv_list)) { 1569 if (pmap == pv->pv_pmap && va == pv->pv_va) 1570 break; 1571 } 1572 } else { 1573 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); 1574 pv; 1575 pv = TAILQ_NEXT(pv, pv_plist)) { 1576 if (va == pv->pv_va) 1577 break; 1578 } 1579 } 1580 1581 rtval = 0; 1582 if (pv) { 1583 1584 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1585 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1586 m->md.pv_list_count--; 1587 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1588 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1589 1590 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1591 free_pv_entry(pv); 1592 } 1593 1594 splx(s); 1595 return rtval; 1596} 1597 1598/* 1599 * Create a pv entry for page at pa for 1600 * (pmap, va). 1601 */ 1602static void 1603pmap_insert_entry(pmap, va, mpte, m) 1604 pmap_t pmap; 1605 vm_offset_t va; 1606 vm_page_t mpte; 1607 vm_page_t m; 1608{ 1609 1610 int s; 1611 pv_entry_t pv; 1612 1613 s = splvm(); 1614 pv = get_pv_entry(); 1615 pv->pv_va = va; 1616 pv->pv_pmap = pmap; 1617 pv->pv_ptem = mpte; 1618 1619 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1620 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1621 m->md.pv_list_count++; 1622 1623 splx(s); 1624} 1625 1626/* 1627 * pmap_remove_pte: do the things to unmap a page in a process 1628 */ 1629static int 1630pmap_remove_pte(pmap, ptq, va) 1631 struct pmap *pmap; 1632 unsigned *ptq; 1633 vm_offset_t va; 1634{ 1635 unsigned oldpte; 1636 vm_page_t m; 1637 1638 oldpte = atomic_readandclear_int(ptq); 1639 if (oldpte & PG_W) 1640 pmap->pm_stats.wired_count -= 1; 1641 /* 1642 * Machines that don't support invlpg, also don't support 1643 * PG_G. 1644 */ 1645 if (oldpte & PG_G) 1646 invlpg(va); 1647 pmap->pm_stats.resident_count -= 1; 1648 if (oldpte & PG_MANAGED) { 1649 m = PHYS_TO_VM_PAGE(oldpte); 1650 if (oldpte & PG_M) { 1651#if defined(PMAP_DIAGNOSTIC) 1652 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1653 printf( 1654 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1655 va, oldpte); 1656 } 1657#endif 1658 if (pmap_track_modified(va)) 1659 vm_page_dirty(m); 1660 } 1661 if (oldpte & PG_A) 1662 vm_page_flag_set(m, PG_REFERENCED); 1663 return pmap_remove_entry(pmap, m, va); 1664 } else { 1665 return pmap_unuse_pt(pmap, va, NULL); 1666 } 1667 1668 return 0; 1669} 1670 1671/* 1672 * Remove a single page from a process address space 1673 */ 1674static void 1675pmap_remove_page(pmap, va) 1676 struct pmap *pmap; 1677 register vm_offset_t va; 1678{ 1679 register unsigned *ptq; 1680 1681 /* 1682 * if there is no pte for this address, just skip it!!! 1683 */ 1684 if (*pmap_pde(pmap, va) == 0) { 1685 return; 1686 } 1687 1688 /* 1689 * get a local va for mappings for this pmap. 1690 */ 1691 ptq = get_ptbase(pmap) + i386_btop(va); 1692 if (*ptq) { 1693 (void) pmap_remove_pte(pmap, ptq, va); 1694 pmap_TLB_invalidate(pmap, va); 1695 } 1696 return; 1697} 1698 1699/* 1700 * Remove the given range of addresses from the specified map. 1701 * 1702 * It is assumed that the start and end are properly 1703 * rounded to the page size. 1704 */ 1705void 1706pmap_remove(pmap, sva, eva) 1707 struct pmap *pmap; 1708 register vm_offset_t sva; 1709 register vm_offset_t eva; 1710{ 1711 register unsigned *ptbase; 1712 vm_offset_t pdnxt; 1713 vm_offset_t ptpaddr; 1714 vm_offset_t sindex, eindex; 1715 int anyvalid; 1716 1717 if (pmap == NULL) 1718 return; 1719 1720 if (pmap->pm_stats.resident_count == 0) 1721 return; 1722 1723 /* 1724 * special handling of removing one page. a very 1725 * common operation and easy to short circuit some 1726 * code. 1727 */ 1728 if (((sva + PAGE_SIZE) == eva) && 1729 (((unsigned) pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1730 pmap_remove_page(pmap, sva); 1731 return; 1732 } 1733 1734 anyvalid = 0; 1735 1736 /* 1737 * Get a local virtual address for the mappings that are being 1738 * worked with. 1739 */ 1740 ptbase = get_ptbase(pmap); 1741 1742 sindex = i386_btop(sva); 1743 eindex = i386_btop(eva); 1744 1745 for (; sindex < eindex; sindex = pdnxt) { 1746 unsigned pdirindex; 1747 1748 /* 1749 * Calculate index for next page table. 1750 */ 1751 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1752 if (pmap->pm_stats.resident_count == 0) 1753 break; 1754 1755 pdirindex = sindex / NPDEPG; 1756 if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) { 1757 pmap->pm_pdir[pdirindex] = 0; 1758 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1759 anyvalid++; 1760 continue; 1761 } 1762 1763 /* 1764 * Weed out invalid mappings. Note: we assume that the page 1765 * directory table is always allocated, and in kernel virtual. 1766 */ 1767 if (ptpaddr == 0) 1768 continue; 1769 1770 /* 1771 * Limit our scan to either the end of the va represented 1772 * by the current page table page, or to the end of the 1773 * range being removed. 1774 */ 1775 if (pdnxt > eindex) { 1776 pdnxt = eindex; 1777 } 1778 1779 for ( ;sindex != pdnxt; sindex++) { 1780 vm_offset_t va; 1781 if (ptbase[sindex] == 0) { 1782 continue; 1783 } 1784 va = i386_ptob(sindex); 1785 1786 anyvalid++; 1787 if (pmap_remove_pte(pmap, 1788 ptbase + sindex, va)) 1789 break; 1790 } 1791 } 1792 1793 if (anyvalid) 1794 pmap_TLB_invalidate_all(pmap); 1795} 1796 1797/* 1798 * Routine: pmap_remove_all 1799 * Function: 1800 * Removes this physical page from 1801 * all physical maps in which it resides. 1802 * Reflects back modify bits to the pager. 1803 * 1804 * Notes: 1805 * Original versions of this routine were very 1806 * inefficient because they iteratively called 1807 * pmap_remove (slow...) 1808 */ 1809 1810static void 1811pmap_remove_all(m) 1812 vm_page_t m; 1813{ 1814 register pv_entry_t pv; 1815 register unsigned *pte, tpte; 1816 int s; 1817 1818#if defined(PMAP_DIAGNOSTIC) 1819 /* 1820 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1821 * pages! 1822 */ 1823 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1824 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1825 } 1826#endif 1827 1828 s = splvm(); 1829 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1830 pv->pv_pmap->pm_stats.resident_count--; 1831 1832 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1833 1834 tpte = atomic_readandclear_int(pte); 1835 if (tpte & PG_W) 1836 pv->pv_pmap->pm_stats.wired_count--; 1837 1838 if (tpte & PG_A) 1839 vm_page_flag_set(m, PG_REFERENCED); 1840 1841 /* 1842 * Update the vm_page_t clean and reference bits. 1843 */ 1844 if (tpte & PG_M) { 1845#if defined(PMAP_DIAGNOSTIC) 1846 if (pmap_nw_modified((pt_entry_t) tpte)) { 1847 printf( 1848 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1849 pv->pv_va, tpte); 1850 } 1851#endif 1852 if (pmap_track_modified(pv->pv_va)) 1853 vm_page_dirty(m); 1854 } 1855 pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va); 1856 1857 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1858 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1859 m->md.pv_list_count--; 1860 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1861 free_pv_entry(pv); 1862 } 1863 1864 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1865 1866 splx(s); 1867} 1868 1869/* 1870 * Set the physical protection on the 1871 * specified range of this map as requested. 1872 */ 1873void 1874pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1875{ 1876 register unsigned *ptbase; 1877 vm_offset_t pdnxt, ptpaddr; 1878 vm_pindex_t sindex, eindex; 1879 int anychanged; 1880 1881 if (pmap == NULL) 1882 return; 1883 1884 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1885 pmap_remove(pmap, sva, eva); 1886 return; 1887 } 1888 1889 if (prot & VM_PROT_WRITE) 1890 return; 1891 1892 anychanged = 0; 1893 1894 ptbase = get_ptbase(pmap); 1895 1896 sindex = i386_btop(sva); 1897 eindex = i386_btop(eva); 1898 1899 for (; sindex < eindex; sindex = pdnxt) { 1900 1901 unsigned pdirindex; 1902 1903 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1904 1905 pdirindex = sindex / NPDEPG; 1906 if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) { 1907 (unsigned) pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1908 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1909 anychanged++; 1910 continue; 1911 } 1912 1913 /* 1914 * Weed out invalid mappings. Note: we assume that the page 1915 * directory table is always allocated, and in kernel virtual. 1916 */ 1917 if (ptpaddr == 0) 1918 continue; 1919 1920 if (pdnxt > eindex) { 1921 pdnxt = eindex; 1922 } 1923 1924 for (; sindex != pdnxt; sindex++) { 1925 1926 unsigned pbits; 1927 vm_page_t m; 1928 1929 pbits = ptbase[sindex]; 1930 1931 if (pbits & PG_MANAGED) { 1932 m = NULL; 1933 if (pbits & PG_A) { 1934 m = PHYS_TO_VM_PAGE(pbits); 1935 vm_page_flag_set(m, PG_REFERENCED); 1936 pbits &= ~PG_A; 1937 } 1938 if (pbits & PG_M) { 1939 if (pmap_track_modified(i386_ptob(sindex))) { 1940 if (m == NULL) 1941 m = PHYS_TO_VM_PAGE(pbits); 1942 vm_page_dirty(m); 1943 pbits &= ~PG_M; 1944 } 1945 } 1946 } 1947 1948 pbits &= ~PG_RW; 1949 1950 if (pbits != ptbase[sindex]) { 1951 ptbase[sindex] = pbits; 1952 anychanged = 1; 1953 } 1954 } 1955 } 1956 if (anychanged) 1957 pmap_TLB_invalidate_all(pmap); 1958} 1959 1960/* 1961 * Insert the given physical page (p) at 1962 * the specified virtual address (v) in the 1963 * target physical map with the protection requested. 1964 * 1965 * If specified, the page will be wired down, meaning 1966 * that the related pte can not be reclaimed. 1967 * 1968 * NB: This is the only routine which MAY NOT lazy-evaluate 1969 * or lose information. That is, this routine must actually 1970 * insert this page into the given map NOW. 1971 */ 1972void 1973pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 1974 boolean_t wired) 1975{ 1976 vm_offset_t pa; 1977 register unsigned *pte; 1978 vm_offset_t opa; 1979 vm_offset_t origpte, newpte; 1980 vm_page_t mpte; 1981 1982 if (pmap == NULL) 1983 return; 1984 1985 va &= PG_FRAME; 1986#ifdef PMAP_DIAGNOSTIC 1987 if (va > VM_MAX_KERNEL_ADDRESS) 1988 panic("pmap_enter: toobig"); 1989 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 1990 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 1991#endif 1992 1993 mpte = NULL; 1994 /* 1995 * In the case that a page table page is not 1996 * resident, we are creating it here. 1997 */ 1998 if (va < UPT_MIN_ADDRESS) { 1999 mpte = pmap_allocpte(pmap, va); 2000 } 2001#if 0 && defined(PMAP_DIAGNOSTIC) 2002 else { 2003 vm_offset_t *pdeaddr = (vm_offset_t *)pmap_pde(pmap, va); 2004 if (((origpte = (vm_offset_t) *pdeaddr) & PG_V) == 0) { 2005 panic("pmap_enter: invalid kernel page table page(0), pdir=%p, pde=%p, va=%p\n", 2006 pmap->pm_pdir[PTDPTDI], origpte, va); 2007 } 2008 if (smp_active) { 2009 pdeaddr = (vm_offset_t *) IdlePTDS[PCPU_GET(cpuid)]; 2010 if (((newpte = pdeaddr[va >> PDRSHIFT]) & PG_V) == 0) { 2011 if ((vm_offset_t) my_idlePTD != (vm_offset_t) vtophys(pdeaddr)) 2012 printf("pde mismatch: %x, %x\n", my_idlePTD, pdeaddr); 2013 printf("cpuid: %d, pdeaddr: 0x%x\n", PCPU_GET(cpuid), pdeaddr); 2014 panic("pmap_enter: invalid kernel page table page(1), pdir=%p, npde=%p, pde=%p, va=%p\n", 2015 pmap->pm_pdir[PTDPTDI], newpte, origpte, va); 2016 } 2017 } 2018 } 2019#endif 2020 2021 pte = pmap_pte(pmap, va); 2022 2023 /* 2024 * Page Directory table entry not valid, we need a new PT page 2025 */ 2026 if (pte == NULL) { 2027 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2028 (void *)pmap->pm_pdir[PTDPTDI], va); 2029 } 2030 2031 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2032 origpte = *(vm_offset_t *)pte; 2033 opa = origpte & PG_FRAME; 2034 2035 if (origpte & PG_PS) 2036 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2037 2038 /* 2039 * Mapping has not changed, must be protection or wiring change. 2040 */ 2041 if (origpte && (opa == pa)) { 2042 /* 2043 * Wiring change, just update stats. We don't worry about 2044 * wiring PT pages as they remain resident as long as there 2045 * are valid mappings in them. Hence, if a user page is wired, 2046 * the PT page will be also. 2047 */ 2048 if (wired && ((origpte & PG_W) == 0)) 2049 pmap->pm_stats.wired_count++; 2050 else if (!wired && (origpte & PG_W)) 2051 pmap->pm_stats.wired_count--; 2052 2053#if defined(PMAP_DIAGNOSTIC) 2054 if (pmap_nw_modified((pt_entry_t) origpte)) { 2055 printf( 2056 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2057 va, origpte); 2058 } 2059#endif 2060 2061 /* 2062 * Remove extra pte reference 2063 */ 2064 if (mpte) 2065 mpte->hold_count--; 2066 2067 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2068 if ((origpte & PG_RW) == 0) { 2069 *pte |= PG_RW; 2070#ifdef SMP 2071 cpu_invlpg((void *)va); 2072 if (pmap->pm_active & PCPU_GET(other_cpus)) 2073 smp_invltlb(); 2074#else 2075 invltlb_1pg(va); 2076#endif 2077 } 2078 return; 2079 } 2080 2081 /* 2082 * We might be turning off write access to the page, 2083 * so we go ahead and sense modify status. 2084 */ 2085 if (origpte & PG_MANAGED) { 2086 if ((origpte & PG_M) && pmap_track_modified(va)) { 2087 vm_page_t om; 2088 om = PHYS_TO_VM_PAGE(opa); 2089 vm_page_dirty(om); 2090 } 2091 pa |= PG_MANAGED; 2092 } 2093 goto validate; 2094 } 2095 /* 2096 * Mapping has changed, invalidate old range and fall through to 2097 * handle validating new mapping. 2098 */ 2099 if (opa) { 2100 int err; 2101 err = pmap_remove_pte(pmap, pte, va); 2102 if (err) 2103 panic("pmap_enter: pte vanished, va: 0x%x", va); 2104 } 2105 2106 /* 2107 * Enter on the PV list if part of our managed memory. Note that we 2108 * raise IPL while manipulating pv_table since pmap_enter can be 2109 * called at interrupt time. 2110 */ 2111 if (pmap_initialized && 2112 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2113 pmap_insert_entry(pmap, va, mpte, m); 2114 pa |= PG_MANAGED; 2115 } 2116 2117 /* 2118 * Increment counters 2119 */ 2120 pmap->pm_stats.resident_count++; 2121 if (wired) 2122 pmap->pm_stats.wired_count++; 2123 2124validate: 2125 /* 2126 * Now validate mapping with desired protection/wiring. 2127 */ 2128 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2129 2130 if (wired) 2131 newpte |= PG_W; 2132 if (va < UPT_MIN_ADDRESS) 2133 newpte |= PG_U; 2134 if (pmap == kernel_pmap) 2135 newpte |= pgeflag; 2136 2137 /* 2138 * if the mapping or permission bits are different, we need 2139 * to update the pte. 2140 */ 2141 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2142 *pte = newpte | PG_A; 2143 /*if (origpte)*/ { 2144#ifdef SMP 2145 cpu_invlpg((void *)va); 2146 if (pmap->pm_active & PCPU_GET(other_cpus)) 2147 smp_invltlb(); 2148#else 2149 invltlb_1pg(va); 2150#endif 2151 } 2152 } 2153} 2154 2155/* 2156 * this code makes some *MAJOR* assumptions: 2157 * 1. Current pmap & pmap exists. 2158 * 2. Not wired. 2159 * 3. Read access. 2160 * 4. No page table pages. 2161 * 5. Tlbflush is deferred to calling procedure. 2162 * 6. Page IS managed. 2163 * but is *MUCH* faster than pmap_enter... 2164 */ 2165 2166static vm_page_t 2167pmap_enter_quick(pmap, va, m, mpte) 2168 register pmap_t pmap; 2169 vm_offset_t va; 2170 vm_page_t m; 2171 vm_page_t mpte; 2172{ 2173 unsigned *pte; 2174 vm_offset_t pa; 2175 2176 /* 2177 * In the case that a page table page is not 2178 * resident, we are creating it here. 2179 */ 2180 if (va < UPT_MIN_ADDRESS) { 2181 unsigned ptepindex; 2182 vm_offset_t ptepa; 2183 2184 /* 2185 * Calculate pagetable page index 2186 */ 2187 ptepindex = va >> PDRSHIFT; 2188 if (mpte && (mpte->pindex == ptepindex)) { 2189 mpte->hold_count++; 2190 } else { 2191retry: 2192 /* 2193 * Get the page directory entry 2194 */ 2195 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 2196 2197 /* 2198 * If the page table page is mapped, we just increment 2199 * the hold count, and activate it. 2200 */ 2201 if (ptepa) { 2202 if (ptepa & PG_PS) 2203 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2204 if (pmap->pm_ptphint && 2205 (pmap->pm_ptphint->pindex == ptepindex)) { 2206 mpte = pmap->pm_ptphint; 2207 } else { 2208 mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex); 2209 pmap->pm_ptphint = mpte; 2210 } 2211 if (mpte == NULL) 2212 goto retry; 2213 mpte->hold_count++; 2214 } else { 2215 mpte = _pmap_allocpte(pmap, ptepindex); 2216 } 2217 } 2218 } else { 2219 mpte = NULL; 2220 } 2221 2222 /* 2223 * This call to vtopte makes the assumption that we are 2224 * entering the page into the current pmap. In order to support 2225 * quick entry into any pmap, one would likely use pmap_pte_quick. 2226 * But that isn't as quick as vtopte. 2227 */ 2228 pte = (unsigned *)vtopte(va); 2229 if (*pte) { 2230 if (mpte) 2231 pmap_unwire_pte_hold(pmap, mpte); 2232 return 0; 2233 } 2234 2235 /* 2236 * Enter on the PV list if part of our managed memory. Note that we 2237 * raise IPL while manipulating pv_table since pmap_enter can be 2238 * called at interrupt time. 2239 */ 2240 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2241 pmap_insert_entry(pmap, va, mpte, m); 2242 2243 /* 2244 * Increment counters 2245 */ 2246 pmap->pm_stats.resident_count++; 2247 2248 pa = VM_PAGE_TO_PHYS(m); 2249 2250 /* 2251 * Now validate mapping with RO protection 2252 */ 2253 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2254 *pte = pa | PG_V | PG_U; 2255 else 2256 *pte = pa | PG_V | PG_U | PG_MANAGED; 2257 2258 return mpte; 2259} 2260 2261/* 2262 * Make a temporary mapping for a physical address. This is only intended 2263 * to be used for panic dumps. 2264 */ 2265void * 2266pmap_kenter_temporary(vm_offset_t pa, int i) 2267{ 2268 pmap_kenter((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa); 2269 return ((void *)crashdumpmap); 2270} 2271 2272#define MAX_INIT_PT (96) 2273/* 2274 * pmap_object_init_pt preloads the ptes for a given object 2275 * into the specified pmap. This eliminates the blast of soft 2276 * faults on process startup and immediately after an mmap. 2277 */ 2278void 2279pmap_object_init_pt(pmap, addr, object, pindex, size, limit) 2280 pmap_t pmap; 2281 vm_offset_t addr; 2282 vm_object_t object; 2283 vm_pindex_t pindex; 2284 vm_size_t size; 2285 int limit; 2286{ 2287 vm_offset_t tmpidx; 2288 int psize; 2289 vm_page_t p, mpte; 2290 int objpgs; 2291 2292 if (pmap == NULL || object == NULL) 2293 return; 2294 2295 /* 2296 * This code maps large physical mmap regions into the 2297 * processor address space. Note that some shortcuts 2298 * are taken, but the code works. 2299 */ 2300 if (pseflag && 2301 (object->type == OBJT_DEVICE) && 2302 ((addr & (NBPDR - 1)) == 0) && 2303 ((size & (NBPDR - 1)) == 0) ) { 2304 int i; 2305 vm_page_t m[1]; 2306 unsigned int ptepindex; 2307 int npdes; 2308 vm_offset_t ptepa; 2309 2310 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2311 return; 2312 2313retry: 2314 p = vm_page_lookup(object, pindex); 2315 if (p && vm_page_sleep_busy(p, FALSE, "init4p")) 2316 goto retry; 2317 2318 if (p == NULL) { 2319 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2320 if (p == NULL) 2321 return; 2322 m[0] = p; 2323 2324 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2325 vm_page_free(p); 2326 return; 2327 } 2328 2329 p = vm_page_lookup(object, pindex); 2330 vm_page_wakeup(p); 2331 } 2332 2333 ptepa = (vm_offset_t) VM_PAGE_TO_PHYS(p); 2334 if (ptepa & (NBPDR - 1)) { 2335 return; 2336 } 2337 2338 p->valid = VM_PAGE_BITS_ALL; 2339 2340 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2341 npdes = size >> PDRSHIFT; 2342 for(i=0;i<npdes;i++) { 2343 pmap->pm_pdir[ptepindex] = 2344 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_PS); 2345 ptepa += NBPDR; 2346 ptepindex += 1; 2347 } 2348 vm_page_flag_set(p, PG_MAPPED); 2349 invltlb(); 2350 return; 2351 } 2352 2353 psize = i386_btop(size); 2354 2355 if ((object->type != OBJT_VNODE) || 2356 (limit && (psize > MAX_INIT_PT) && 2357 (object->resident_page_count > MAX_INIT_PT))) { 2358 return; 2359 } 2360 2361 if (psize + pindex > object->size) { 2362 if (object->size < pindex) 2363 return; 2364 psize = object->size - pindex; 2365 } 2366 2367 mpte = NULL; 2368 /* 2369 * if we are processing a major portion of the object, then scan the 2370 * entire thing. 2371 */ 2372 if (psize > (object->resident_page_count >> 2)) { 2373 objpgs = psize; 2374 2375 for (p = TAILQ_FIRST(&object->memq); 2376 ((objpgs > 0) && (p != NULL)); 2377 p = TAILQ_NEXT(p, listq)) { 2378 2379 tmpidx = p->pindex; 2380 if (tmpidx < pindex) { 2381 continue; 2382 } 2383 tmpidx -= pindex; 2384 if (tmpidx >= psize) { 2385 continue; 2386 } 2387 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2388 (p->busy == 0) && 2389 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2390 if ((p->queue - p->pc) == PQ_CACHE) 2391 vm_page_deactivate(p); 2392 vm_page_busy(p); 2393 mpte = pmap_enter_quick(pmap, 2394 addr + i386_ptob(tmpidx), p, mpte); 2395 vm_page_flag_set(p, PG_MAPPED); 2396 vm_page_wakeup(p); 2397 } 2398 objpgs -= 1; 2399 } 2400 } else { 2401 /* 2402 * else lookup the pages one-by-one. 2403 */ 2404 for (tmpidx = 0; tmpidx < psize; tmpidx += 1) { 2405 p = vm_page_lookup(object, tmpidx + pindex); 2406 if (p && 2407 ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2408 (p->busy == 0) && 2409 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2410 if ((p->queue - p->pc) == PQ_CACHE) 2411 vm_page_deactivate(p); 2412 vm_page_busy(p); 2413 mpte = pmap_enter_quick(pmap, 2414 addr + i386_ptob(tmpidx), p, mpte); 2415 vm_page_flag_set(p, PG_MAPPED); 2416 vm_page_wakeup(p); 2417 } 2418 } 2419 } 2420 return; 2421} 2422 2423/* 2424 * pmap_prefault provides a quick way of clustering 2425 * pagefaults into a processes address space. It is a "cousin" 2426 * of pmap_object_init_pt, except it runs at page fault time instead 2427 * of mmap time. 2428 */ 2429#define PFBAK 4 2430#define PFFOR 4 2431#define PAGEORDER_SIZE (PFBAK+PFFOR) 2432 2433static int pmap_prefault_pageorder[] = { 2434 -PAGE_SIZE, PAGE_SIZE, 2435 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2436 -3 * PAGE_SIZE, 3 * PAGE_SIZE 2437 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2438}; 2439 2440void 2441pmap_prefault(pmap, addra, entry) 2442 pmap_t pmap; 2443 vm_offset_t addra; 2444 vm_map_entry_t entry; 2445{ 2446 int i; 2447 vm_offset_t starta; 2448 vm_offset_t addr; 2449 vm_pindex_t pindex; 2450 vm_page_t m, mpte; 2451 vm_object_t object; 2452 2453 if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace))) 2454 return; 2455 2456 object = entry->object.vm_object; 2457 2458 starta = addra - PFBAK * PAGE_SIZE; 2459 if (starta < entry->start) { 2460 starta = entry->start; 2461 } else if (starta > addra) { 2462 starta = 0; 2463 } 2464 2465 mpte = NULL; 2466 for (i = 0; i < PAGEORDER_SIZE; i++) { 2467 vm_object_t lobject; 2468 unsigned *pte; 2469 2470 addr = addra + pmap_prefault_pageorder[i]; 2471 if (addr > addra + (PFFOR * PAGE_SIZE)) 2472 addr = 0; 2473 2474 if (addr < starta || addr >= entry->end) 2475 continue; 2476 2477 if ((*pmap_pde(pmap, addr)) == NULL) 2478 continue; 2479 2480 pte = (unsigned *) vtopte(addr); 2481 if (*pte) 2482 continue; 2483 2484 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2485 lobject = object; 2486 for (m = vm_page_lookup(lobject, pindex); 2487 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2488 lobject = lobject->backing_object) { 2489 if (lobject->backing_object_offset & PAGE_MASK) 2490 break; 2491 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2492 m = vm_page_lookup(lobject->backing_object, pindex); 2493 } 2494 2495 /* 2496 * give-up when a page is not in memory 2497 */ 2498 if (m == NULL) 2499 break; 2500 2501 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2502 (m->busy == 0) && 2503 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2504 2505 if ((m->queue - m->pc) == PQ_CACHE) { 2506 vm_page_deactivate(m); 2507 } 2508 vm_page_busy(m); 2509 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2510 vm_page_flag_set(m, PG_MAPPED); 2511 vm_page_wakeup(m); 2512 } 2513 } 2514} 2515 2516/* 2517 * Routine: pmap_change_wiring 2518 * Function: Change the wiring attribute for a map/virtual-address 2519 * pair. 2520 * In/out conditions: 2521 * The mapping must already exist in the pmap. 2522 */ 2523void 2524pmap_change_wiring(pmap, va, wired) 2525 register pmap_t pmap; 2526 vm_offset_t va; 2527 boolean_t wired; 2528{ 2529 register unsigned *pte; 2530 2531 if (pmap == NULL) 2532 return; 2533 2534 pte = pmap_pte(pmap, va); 2535 2536 if (wired && !pmap_pte_w(pte)) 2537 pmap->pm_stats.wired_count++; 2538 else if (!wired && pmap_pte_w(pte)) 2539 pmap->pm_stats.wired_count--; 2540 2541 /* 2542 * Wiring is not a hardware characteristic so there is no need to 2543 * invalidate TLB. 2544 */ 2545 pmap_pte_set_w(pte, wired); 2546} 2547 2548 2549 2550/* 2551 * Copy the range specified by src_addr/len 2552 * from the source map to the range dst_addr/len 2553 * in the destination map. 2554 * 2555 * This routine is only advisory and need not do anything. 2556 */ 2557 2558void 2559pmap_copy(dst_pmap, src_pmap, dst_addr, len, src_addr) 2560 pmap_t dst_pmap, src_pmap; 2561 vm_offset_t dst_addr; 2562 vm_size_t len; 2563 vm_offset_t src_addr; 2564{ 2565 vm_offset_t addr; 2566 vm_offset_t end_addr = src_addr + len; 2567 vm_offset_t pdnxt; 2568 unsigned src_frame, dst_frame; 2569 vm_page_t m; 2570 2571 if (dst_addr != src_addr) 2572 return; 2573 2574 src_frame = ((unsigned) src_pmap->pm_pdir[PTDPTDI]) & PG_FRAME; 2575 if (src_frame != (((unsigned) PTDpde) & PG_FRAME)) { 2576 return; 2577 } 2578 2579 dst_frame = ((unsigned) dst_pmap->pm_pdir[PTDPTDI]) & PG_FRAME; 2580 if (dst_frame != (((unsigned) APTDpde) & PG_FRAME)) { 2581 APTDpde = (pd_entry_t) (dst_frame | PG_RW | PG_V); 2582#if defined(SMP) 2583 /* The page directory is not shared between CPUs */ 2584 cpu_invltlb(); 2585#else 2586 invltlb(); 2587#endif 2588 } 2589 2590 for(addr = src_addr; addr < end_addr; addr = pdnxt) { 2591 unsigned *src_pte, *dst_pte; 2592 vm_page_t dstmpte, srcmpte; 2593 vm_offset_t srcptepaddr; 2594 unsigned ptepindex; 2595 2596 if (addr >= UPT_MIN_ADDRESS) 2597 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2598 2599 /* 2600 * Don't let optional prefaulting of pages make us go 2601 * way below the low water mark of free pages or way 2602 * above high water mark of used pv entries. 2603 */ 2604 if (cnt.v_free_count < cnt.v_free_reserved || 2605 pv_entry_count > pv_entry_high_water) 2606 break; 2607 2608 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2609 ptepindex = addr >> PDRSHIFT; 2610 2611 srcptepaddr = (vm_offset_t) src_pmap->pm_pdir[ptepindex]; 2612 if (srcptepaddr == 0) 2613 continue; 2614 2615 if (srcptepaddr & PG_PS) { 2616 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2617 dst_pmap->pm_pdir[ptepindex] = (pd_entry_t) srcptepaddr; 2618 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2619 } 2620 continue; 2621 } 2622 2623 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2624 if ((srcmpte == NULL) || 2625 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2626 continue; 2627 2628 if (pdnxt > end_addr) 2629 pdnxt = end_addr; 2630 2631 src_pte = (unsigned *) vtopte(addr); 2632 dst_pte = (unsigned *) avtopte(addr); 2633 while (addr < pdnxt) { 2634 unsigned ptetemp; 2635 ptetemp = *src_pte; 2636 /* 2637 * we only virtual copy managed pages 2638 */ 2639 if ((ptetemp & PG_MANAGED) != 0) { 2640 /* 2641 * We have to check after allocpte for the 2642 * pte still being around... allocpte can 2643 * block. 2644 */ 2645 dstmpte = pmap_allocpte(dst_pmap, addr); 2646 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2647 /* 2648 * Clear the modified and 2649 * accessed (referenced) bits 2650 * during the copy. 2651 */ 2652 m = PHYS_TO_VM_PAGE(ptetemp); 2653 *dst_pte = ptetemp & ~(PG_M | PG_A); 2654 dst_pmap->pm_stats.resident_count++; 2655 pmap_insert_entry(dst_pmap, addr, 2656 dstmpte, m); 2657 } else { 2658 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2659 } 2660 if (dstmpte->hold_count >= srcmpte->hold_count) 2661 break; 2662 } 2663 addr += PAGE_SIZE; 2664 src_pte++; 2665 dst_pte++; 2666 } 2667 } 2668} 2669 2670/* 2671 * Routine: pmap_kernel 2672 * Function: 2673 * Returns the physical map handle for the kernel. 2674 */ 2675pmap_t 2676pmap_kernel() 2677{ 2678 return (kernel_pmap); 2679} 2680 2681/* 2682 * pmap_zero_page zeros the specified hardware page by mapping 2683 * the page into KVM and using bzero to clear its contents. 2684 */ 2685void 2686pmap_zero_page(phys) 2687 vm_offset_t phys; 2688{ 2689 2690 if (*(int *) CMAP2) 2691 panic("pmap_zero_page: CMAP2 busy"); 2692 2693 *(int *) CMAP2 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M; 2694 invltlb_1pg((vm_offset_t)CADDR2); 2695 2696#if defined(I686_CPU) 2697 if (cpu_class == CPUCLASS_686) 2698 i686_pagezero(CADDR2); 2699 else 2700#endif 2701 bzero(CADDR2, PAGE_SIZE); 2702 *(int *) CMAP2 = 0; 2703} 2704 2705/* 2706 * pmap_zero_page_area zeros the specified hardware page by mapping 2707 * the page into KVM and using bzero to clear its contents. 2708 * 2709 * off and size may not cover an area beyond a single hardware page. 2710 */ 2711void 2712pmap_zero_page_area(phys, off, size) 2713 vm_offset_t phys; 2714 int off; 2715 int size; 2716{ 2717 2718 if (*(int *) CMAP2) 2719 panic("pmap_zero_page: CMAP2 busy"); 2720 2721 *(int *) CMAP2 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M; 2722 invltlb_1pg((vm_offset_t)CADDR2); 2723 2724#if defined(I686_CPU) 2725 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2726 i686_pagezero(CADDR2); 2727 else 2728#endif 2729 bzero((char *)CADDR2 + off, size); 2730 *(int *) CMAP2 = 0; 2731} 2732 2733/* 2734 * pmap_copy_page copies the specified (machine independent) 2735 * page by mapping the page into virtual memory and using 2736 * bcopy to copy the page, one machine dependent page at a 2737 * time. 2738 */ 2739void 2740pmap_copy_page(src, dst) 2741 vm_offset_t src; 2742 vm_offset_t dst; 2743{ 2744 2745 if (*(int *) CMAP1) 2746 panic("pmap_copy_page: CMAP1 busy"); 2747 if (*(int *) CMAP2) 2748 panic("pmap_copy_page: CMAP2 busy"); 2749 2750 *(int *) CMAP1 = PG_V | (src & PG_FRAME) | PG_A; 2751 *(int *) CMAP2 = PG_V | PG_RW | (dst & PG_FRAME) | PG_A | PG_M; 2752#ifdef I386_CPU 2753 invltlb(); 2754#else 2755 invlpg((u_int)CADDR1); 2756 invlpg((u_int)CADDR2); 2757#endif 2758 2759 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2760 2761 *(int *) CMAP1 = 0; 2762 *(int *) CMAP2 = 0; 2763} 2764 2765 2766/* 2767 * Routine: pmap_pageable 2768 * Function: 2769 * Make the specified pages (by pmap, offset) 2770 * pageable (or not) as requested. 2771 * 2772 * A page which is not pageable may not take 2773 * a fault; therefore, its page table entry 2774 * must remain valid for the duration. 2775 * 2776 * This routine is merely advisory; pmap_enter 2777 * will specify that these pages are to be wired 2778 * down (or not) as appropriate. 2779 */ 2780void 2781pmap_pageable(pmap, sva, eva, pageable) 2782 pmap_t pmap; 2783 vm_offset_t sva, eva; 2784 boolean_t pageable; 2785{ 2786} 2787 2788/* 2789 * this routine returns true if a physical page resides 2790 * in the given pmap. 2791 */ 2792boolean_t 2793pmap_page_exists(pmap, m) 2794 pmap_t pmap; 2795 vm_page_t m; 2796{ 2797 register pv_entry_t pv; 2798 int s; 2799 2800 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2801 return FALSE; 2802 2803 s = splvm(); 2804 2805 /* 2806 * Not found, check current mappings returning immediately if found. 2807 */ 2808 for (pv = TAILQ_FIRST(&m->md.pv_list); 2809 pv; 2810 pv = TAILQ_NEXT(pv, pv_list)) { 2811 if (pv->pv_pmap == pmap) { 2812 splx(s); 2813 return TRUE; 2814 } 2815 } 2816 splx(s); 2817 return (FALSE); 2818} 2819 2820#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2821/* 2822 * Remove all pages from specified address space 2823 * this aids process exit speeds. Also, this code 2824 * is special cased for current process only, but 2825 * can have the more generic (and slightly slower) 2826 * mode enabled. This is much faster than pmap_remove 2827 * in the case of running down an entire address space. 2828 */ 2829void 2830pmap_remove_pages(pmap, sva, eva) 2831 pmap_t pmap; 2832 vm_offset_t sva, eva; 2833{ 2834 unsigned *pte, tpte; 2835 pv_entry_t pv, npv; 2836 int s; 2837 vm_page_t m; 2838 2839#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2840 if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace))) { 2841 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2842 return; 2843 } 2844#endif 2845 2846 s = splvm(); 2847 for(pv = TAILQ_FIRST(&pmap->pm_pvlist); 2848 pv; 2849 pv = npv) { 2850 2851 if (pv->pv_va >= eva || pv->pv_va < sva) { 2852 npv = TAILQ_NEXT(pv, pv_plist); 2853 continue; 2854 } 2855 2856#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2857 pte = (unsigned *)vtopte(pv->pv_va); 2858#else 2859 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2860#endif 2861 tpte = *pte; 2862 2863/* 2864 * We cannot remove wired pages from a process' mapping at this time 2865 */ 2866 if (tpte & PG_W) { 2867 npv = TAILQ_NEXT(pv, pv_plist); 2868 continue; 2869 } 2870 *pte = 0; 2871 2872 m = PHYS_TO_VM_PAGE(tpte); 2873 2874 KASSERT(m < &vm_page_array[vm_page_array_size], 2875 ("pmap_remove_pages: bad tpte %x", tpte)); 2876 2877 pv->pv_pmap->pm_stats.resident_count--; 2878 2879 /* 2880 * Update the vm_page_t clean and reference bits. 2881 */ 2882 if (tpte & PG_M) { 2883 vm_page_dirty(m); 2884 } 2885 2886 2887 npv = TAILQ_NEXT(pv, pv_plist); 2888 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 2889 2890 m->md.pv_list_count--; 2891 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 2892 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 2893 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 2894 } 2895 2896 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 2897 free_pv_entry(pv); 2898 } 2899 splx(s); 2900 pmap_TLB_invalidate_all(pmap); 2901} 2902 2903/* 2904 * pmap_testbit tests bits in pte's 2905 * note that the testbit/changebit routines are inline, 2906 * and a lot of things compile-time evaluate. 2907 */ 2908static boolean_t 2909pmap_testbit(m, bit) 2910 vm_page_t m; 2911 int bit; 2912{ 2913 pv_entry_t pv; 2914 unsigned *pte; 2915 int s; 2916 2917 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2918 return FALSE; 2919 2920 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 2921 return FALSE; 2922 2923 s = splvm(); 2924 2925 for (pv = TAILQ_FIRST(&m->md.pv_list); 2926 pv; 2927 pv = TAILQ_NEXT(pv, pv_list)) { 2928 2929 /* 2930 * if the bit being tested is the modified bit, then 2931 * mark clean_map and ptes as never 2932 * modified. 2933 */ 2934 if (bit & (PG_A|PG_M)) { 2935 if (!pmap_track_modified(pv->pv_va)) 2936 continue; 2937 } 2938 2939#if defined(PMAP_DIAGNOSTIC) 2940 if (!pv->pv_pmap) { 2941 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 2942 continue; 2943 } 2944#endif 2945 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2946 if (*pte & bit) { 2947 splx(s); 2948 return TRUE; 2949 } 2950 } 2951 splx(s); 2952 return (FALSE); 2953} 2954 2955/* 2956 * this routine is used to modify bits in ptes 2957 */ 2958static __inline void 2959pmap_changebit(m, bit, setem) 2960 vm_page_t m; 2961 int bit; 2962 boolean_t setem; 2963{ 2964 register pv_entry_t pv; 2965 register unsigned *pte; 2966 int s; 2967 2968 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2969 return; 2970 2971 s = splvm(); 2972 2973 /* 2974 * Loop over all current mappings setting/clearing as appropos If 2975 * setting RO do we need to clear the VAC? 2976 */ 2977 for (pv = TAILQ_FIRST(&m->md.pv_list); 2978 pv; 2979 pv = TAILQ_NEXT(pv, pv_list)) { 2980 2981 /* 2982 * don't write protect pager mappings 2983 */ 2984 if (!setem && (bit == PG_RW)) { 2985 if (!pmap_track_modified(pv->pv_va)) 2986 continue; 2987 } 2988 2989#if defined(PMAP_DIAGNOSTIC) 2990 if (!pv->pv_pmap) { 2991 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 2992 continue; 2993 } 2994#endif 2995 2996 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2997 2998 if (setem) { 2999 *(int *)pte |= bit; 3000 pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va); 3001 } else { 3002 vm_offset_t pbits = *(vm_offset_t *)pte; 3003 if (pbits & bit) { 3004 if (bit == PG_RW) { 3005 if (pbits & PG_M) { 3006 vm_page_dirty(m); 3007 } 3008 *(int *)pte = pbits & ~(PG_M|PG_RW); 3009 } else { 3010 *(int *)pte = pbits & ~bit; 3011 } 3012 pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va); 3013 } 3014 } 3015 } 3016 splx(s); 3017} 3018 3019/* 3020 * pmap_page_protect: 3021 * 3022 * Lower the permission for all mappings to a given page. 3023 */ 3024void 3025pmap_page_protect(vm_page_t m, vm_prot_t prot) 3026{ 3027 if ((prot & VM_PROT_WRITE) == 0) { 3028 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3029 pmap_changebit(m, PG_RW, FALSE); 3030 } else { 3031 pmap_remove_all(m); 3032 } 3033 } 3034} 3035 3036vm_offset_t 3037pmap_phys_address(ppn) 3038 int ppn; 3039{ 3040 return (i386_ptob(ppn)); 3041} 3042 3043/* 3044 * pmap_ts_referenced: 3045 * 3046 * Return the count of reference bits for a page, clearing all of them. 3047 */ 3048int 3049pmap_ts_referenced(vm_page_t m) 3050{ 3051 register pv_entry_t pv, pvf, pvn; 3052 unsigned *pte; 3053 int s; 3054 int rtval = 0; 3055 3056 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3057 return (rtval); 3058 3059 s = splvm(); 3060 3061 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3062 3063 pvf = pv; 3064 3065 do { 3066 pvn = TAILQ_NEXT(pv, pv_list); 3067 3068 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3069 3070 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3071 3072 if (!pmap_track_modified(pv->pv_va)) 3073 continue; 3074 3075 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3076 3077 if (pte && (*pte & PG_A)) { 3078 *pte &= ~PG_A; 3079 3080 pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va); 3081 3082 rtval++; 3083 if (rtval > 4) { 3084 break; 3085 } 3086 } 3087 } while ((pv = pvn) != NULL && pv != pvf); 3088 } 3089 splx(s); 3090 3091 return (rtval); 3092} 3093 3094/* 3095 * pmap_is_modified: 3096 * 3097 * Return whether or not the specified physical page was modified 3098 * in any physical maps. 3099 */ 3100boolean_t 3101pmap_is_modified(vm_page_t m) 3102{ 3103 return pmap_testbit(m, PG_M); 3104} 3105 3106/* 3107 * Clear the modify bits on the specified physical page. 3108 */ 3109void 3110pmap_clear_modify(vm_page_t m) 3111{ 3112 pmap_changebit(m, PG_M, FALSE); 3113} 3114 3115/* 3116 * pmap_clear_reference: 3117 * 3118 * Clear the reference bit on the specified physical page. 3119 */ 3120void 3121pmap_clear_reference(vm_page_t m) 3122{ 3123 pmap_changebit(m, PG_A, FALSE); 3124} 3125 3126/* 3127 * Miscellaneous support routines follow 3128 */ 3129 3130static void 3131i386_protection_init() 3132{ 3133 register int *kp, prot; 3134 3135 kp = protection_codes; 3136 for (prot = 0; prot < 8; prot++) { 3137 switch (prot) { 3138 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3139 /* 3140 * Read access is also 0. There isn't any execute bit, 3141 * so just make it readable. 3142 */ 3143 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3144 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3145 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3146 *kp++ = 0; 3147 break; 3148 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3149 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3150 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3151 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3152 *kp++ = PG_RW; 3153 break; 3154 } 3155 } 3156} 3157 3158/* 3159 * Map a set of physical memory pages into the kernel virtual 3160 * address space. Return a pointer to where it is mapped. This 3161 * routine is intended to be used for mapping device memory, 3162 * NOT real memory. 3163 */ 3164void * 3165pmap_mapdev(pa, size) 3166 vm_offset_t pa; 3167 vm_size_t size; 3168{ 3169 vm_offset_t va, tmpva, offset; 3170 unsigned *pte; 3171 3172 offset = pa & PAGE_MASK; 3173 size = roundup(offset + size, PAGE_SIZE); 3174 3175 GIANT_REQUIRED; 3176 3177 va = kmem_alloc_pageable(kernel_map, size); 3178 if (!va) 3179 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3180 3181 pa = pa & PG_FRAME; 3182 for (tmpva = va; size > 0;) { 3183 pte = (unsigned *)vtopte(tmpva); 3184 *pte = pa | PG_RW | PG_V | pgeflag; 3185 size -= PAGE_SIZE; 3186 tmpva += PAGE_SIZE; 3187 pa += PAGE_SIZE; 3188 } 3189 invltlb(); 3190 3191 return ((void *)(va + offset)); 3192} 3193 3194void 3195pmap_unmapdev(va, size) 3196 vm_offset_t va; 3197 vm_size_t size; 3198{ 3199 vm_offset_t base, offset; 3200 3201 base = va & PG_FRAME; 3202 offset = va & PAGE_MASK; 3203 size = roundup(offset + size, PAGE_SIZE); 3204 kmem_free(kernel_map, base, size); 3205} 3206 3207/* 3208 * perform the pmap work for mincore 3209 */ 3210int 3211pmap_mincore(pmap, addr) 3212 pmap_t pmap; 3213 vm_offset_t addr; 3214{ 3215 3216 unsigned *ptep, pte; 3217 vm_page_t m; 3218 int val = 0; 3219 3220 ptep = pmap_pte(pmap, addr); 3221 if (ptep == 0) { 3222 return 0; 3223 } 3224 3225 if ((pte = *ptep) != 0) { 3226 vm_offset_t pa; 3227 3228 val = MINCORE_INCORE; 3229 if ((pte & PG_MANAGED) == 0) 3230 return val; 3231 3232 pa = pte & PG_FRAME; 3233 3234 m = PHYS_TO_VM_PAGE(pa); 3235 3236 /* 3237 * Modified by us 3238 */ 3239 if (pte & PG_M) 3240 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3241 /* 3242 * Modified by someone 3243 */ 3244 else if (m->dirty || pmap_is_modified(m)) 3245 val |= MINCORE_MODIFIED_OTHER; 3246 /* 3247 * Referenced by us 3248 */ 3249 if (pte & PG_A) 3250 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3251 3252 /* 3253 * Referenced by someone 3254 */ 3255 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3256 val |= MINCORE_REFERENCED_OTHER; 3257 vm_page_flag_set(m, PG_REFERENCED); 3258 } 3259 } 3260 return val; 3261} 3262 3263void 3264pmap_activate(struct proc *p) 3265{ 3266 pmap_t pmap; 3267 3268 pmap = vmspace_pmap(p->p_vmspace); 3269#if defined(SMP) 3270 pmap->pm_active |= 1 << PCPU_GET(cpuid); 3271#else 3272 pmap->pm_active |= 1; 3273#endif 3274#if defined(SWTCH_OPTIM_STATS) 3275 tlb_flush_count++; 3276#endif 3277 load_cr3(p->p_addr->u_pcb.pcb_cr3 = vtophys(pmap->pm_pdir)); 3278} 3279 3280vm_offset_t 3281pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3282{ 3283 3284 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3285 return addr; 3286 } 3287 3288 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3289 return addr; 3290} 3291 3292 3293#if defined(PMAP_DEBUG) 3294pmap_pid_dump(int pid) 3295{ 3296 pmap_t pmap; 3297 struct proc *p; 3298 int npte = 0; 3299 int index; 3300 3301 sx_slock(&allproc_lock); 3302 LIST_FOREACH(p, &allproc, p_list) { 3303 if (p->p_pid != pid) 3304 continue; 3305 3306 if (p->p_vmspace) { 3307 int i,j; 3308 index = 0; 3309 pmap = vmspace_pmap(p->p_vmspace); 3310 for(i=0;i<1024;i++) { 3311 pd_entry_t *pde; 3312 unsigned *pte; 3313 unsigned base = i << PDRSHIFT; 3314 3315 pde = &pmap->pm_pdir[i]; 3316 if (pde && pmap_pde_v(pde)) { 3317 for(j=0;j<1024;j++) { 3318 unsigned va = base + (j << PAGE_SHIFT); 3319 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3320 if (index) { 3321 index = 0; 3322 printf("\n"); 3323 } 3324 sx_sunlock(&allproc_lock); 3325 return npte; 3326 } 3327 pte = pmap_pte_quick( pmap, va); 3328 if (pte && pmap_pte_v(pte)) { 3329 vm_offset_t pa; 3330 vm_page_t m; 3331 pa = *(int *)pte; 3332 m = PHYS_TO_VM_PAGE(pa); 3333 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3334 va, pa, m->hold_count, m->wire_count, m->flags); 3335 npte++; 3336 index++; 3337 if (index >= 2) { 3338 index = 0; 3339 printf("\n"); 3340 } else { 3341 printf(" "); 3342 } 3343 } 3344 } 3345 } 3346 } 3347 } 3348 } 3349 sx_sunlock(&allproc_lock); 3350 return npte; 3351} 3352#endif 3353 3354#if defined(DEBUG) 3355 3356static void pads __P((pmap_t pm)); 3357void pmap_pvdump __P((vm_offset_t pa)); 3358 3359/* print address space of pmap*/ 3360static void 3361pads(pm) 3362 pmap_t pm; 3363{ 3364 unsigned va, i, j; 3365 unsigned *ptep; 3366 3367 if (pm == kernel_pmap) 3368 return; 3369 for (i = 0; i < 1024; i++) 3370 if (pm->pm_pdir[i]) 3371 for (j = 0; j < 1024; j++) { 3372 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3373 if (pm == kernel_pmap && va < KERNBASE) 3374 continue; 3375 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3376 continue; 3377 ptep = pmap_pte_quick(pm, va); 3378 if (pmap_pte_v(ptep)) 3379 printf("%x:%x ", va, *(int *) ptep); 3380 }; 3381 3382} 3383 3384void 3385pmap_pvdump(pa) 3386 vm_offset_t pa; 3387{ 3388 register pv_entry_t pv; 3389 vm_page_t m; 3390 3391 printf("pa %x", pa); 3392 m = PHYS_TO_VM_PAGE(pa); 3393 for (pv = TAILQ_FIRST(&m->md.pv_list); 3394 pv; 3395 pv = TAILQ_NEXT(pv, pv_list)) { 3396#ifdef used_to_be 3397 printf(" -> pmap %p, va %x, flags %x", 3398 (void *)pv->pv_pmap, pv->pv_va, pv->pv_flags); 3399#endif 3400 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3401 pads(pv->pv_pmap); 3402 } 3403 printf(" "); 3404} 3405#endif 3406