pmap.c revision 73862
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 73862 2001-03-06 06:06:42Z jhb $ 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 75#include <sys/param.h> 76#include <sys/systm.h> 77#include <sys/proc.h> 78#include <sys/msgbuf.h> 79#include <sys/vmmeter.h> 80#include <sys/mman.h> 81 82#include <vm/vm.h> 83#include <vm/vm_param.h> 84#include <sys/lock.h> 85#include <vm/vm_kern.h> 86#include <vm/vm_page.h> 87#include <vm/vm_map.h> 88#include <vm/vm_object.h> 89#include <vm/vm_extern.h> 90#include <vm/vm_pageout.h> 91#include <vm/vm_pager.h> 92#include <vm/vm_zone.h> 93 94#include <sys/user.h> 95 96#include <machine/cputypes.h> 97#include <machine/md_var.h> 98#include <machine/specialreg.h> 99#if defined(SMP) || defined(APIC_IO) 100#include <machine/smp.h> 101#include <machine/apic.h> 102#include <machine/segments.h> 103#include <machine/tss.h> 104#include <machine/globaldata.h> 105#endif /* SMP || APIC_IO */ 106 107#define PMAP_KEEP_PDIRS 108#ifndef PMAP_SHPGPERPROC 109#define PMAP_SHPGPERPROC 200 110#endif 111 112#if defined(DIAGNOSTIC) 113#define PMAP_DIAGNOSTIC 114#endif 115 116#define MINPV 2048 117 118#if !defined(PMAP_DIAGNOSTIC) 119#define PMAP_INLINE __inline 120#else 121#define PMAP_INLINE 122#endif 123 124/* 125 * Get PDEs and PTEs for user/kernel address space 126 */ 127#define pmap_pde(m, v) (&((m)->pm_pdir[(vm_offset_t)(v) >> PDRSHIFT])) 128#define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT]) 129 130#define pmap_pde_v(pte) ((*(int *)pte & PG_V) != 0) 131#define pmap_pte_w(pte) ((*(int *)pte & PG_W) != 0) 132#define pmap_pte_m(pte) ((*(int *)pte & PG_M) != 0) 133#define pmap_pte_u(pte) ((*(int *)pte & PG_A) != 0) 134#define pmap_pte_v(pte) ((*(int *)pte & PG_V) != 0) 135 136#define pmap_pte_set_w(pte, v) ((v)?(*(int *)pte |= PG_W):(*(int *)pte &= ~PG_W)) 137#define pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v))) 138 139/* 140 * Given a map and a machine independent protection code, 141 * convert to a vax protection code. 142 */ 143#define pte_prot(m, p) (protection_codes[p]) 144static int protection_codes[8]; 145 146static struct pmap kernel_pmap_store; 147pmap_t kernel_pmap; 148LIST_HEAD(pmaplist, pmap); 149struct pmaplist allpmaps; 150 151vm_offset_t avail_start; /* PA of first available physical page */ 152vm_offset_t avail_end; /* PA of last available physical page */ 153vm_offset_t virtual_avail; /* VA of first avail page (after kernel bss) */ 154vm_offset_t virtual_end; /* VA of last avail page (end of kernel AS) */ 155static boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */ 156static int pgeflag; /* PG_G or-in */ 157static int pseflag; /* PG_PS or-in */ 158 159static vm_object_t kptobj; 160 161static int nkpt; 162vm_offset_t kernel_vm_end; 163 164/* 165 * Data for the pv entry allocation mechanism 166 */ 167static vm_zone_t pvzone; 168static struct vm_zone pvzone_store; 169static struct vm_object pvzone_obj; 170static int pv_entry_count=0, pv_entry_max=0, pv_entry_high_water=0; 171static int pmap_pagedaemon_waken = 0; 172static struct pv_entry *pvinit; 173 174/* 175 * All those kernel PT submaps that BSD is so fond of 176 */ 177pt_entry_t *CMAP1 = 0; 178static pt_entry_t *CMAP2, *ptmmap; 179caddr_t CADDR1 = 0, ptvmmap = 0; 180static caddr_t CADDR2; 181static pt_entry_t *msgbufmap; 182struct msgbuf *msgbufp=0; 183 184/* 185 * Crashdump maps. 186 */ 187static pt_entry_t *pt_crashdumpmap; 188static caddr_t crashdumpmap; 189 190#ifdef SMP 191extern pt_entry_t *SMPpt; 192#endif 193static pt_entry_t *PMAP1 = 0; 194static unsigned *PADDR1 = 0; 195 196static PMAP_INLINE void free_pv_entry __P((pv_entry_t pv)); 197static unsigned * get_ptbase __P((pmap_t pmap)); 198static pv_entry_t get_pv_entry __P((void)); 199static void i386_protection_init __P((void)); 200static __inline void pmap_changebit __P((vm_page_t m, int bit, boolean_t setem)); 201 202static void pmap_remove_all __P((vm_page_t m)); 203static vm_page_t pmap_enter_quick __P((pmap_t pmap, vm_offset_t va, 204 vm_page_t m, vm_page_t mpte)); 205static int pmap_remove_pte __P((struct pmap *pmap, unsigned *ptq, 206 vm_offset_t sva)); 207static void pmap_remove_page __P((struct pmap *pmap, vm_offset_t va)); 208static int pmap_remove_entry __P((struct pmap *pmap, vm_page_t m, 209 vm_offset_t va)); 210static boolean_t pmap_testbit __P((vm_page_t m, int bit)); 211static void pmap_insert_entry __P((pmap_t pmap, vm_offset_t va, 212 vm_page_t mpte, vm_page_t m)); 213 214static vm_page_t pmap_allocpte __P((pmap_t pmap, vm_offset_t va)); 215 216static int pmap_release_free_page __P((pmap_t pmap, vm_page_t p)); 217static vm_page_t _pmap_allocpte __P((pmap_t pmap, unsigned ptepindex)); 218static unsigned * pmap_pte_quick __P((pmap_t pmap, vm_offset_t va)); 219static vm_page_t pmap_page_lookup __P((vm_object_t object, vm_pindex_t pindex)); 220static int pmap_unuse_pt __P((pmap_t, vm_offset_t, vm_page_t)); 221static vm_offset_t pmap_kmem_choose(vm_offset_t addr); 222 223static unsigned pdir4mb; 224 225/* 226 * Routine: pmap_pte 227 * Function: 228 * Extract the page table entry associated 229 * with the given map/virtual_address pair. 230 */ 231 232PMAP_INLINE unsigned * 233pmap_pte(pmap, va) 234 register pmap_t pmap; 235 vm_offset_t va; 236{ 237 unsigned *pdeaddr; 238 239 if (pmap) { 240 pdeaddr = (unsigned *) pmap_pde(pmap, va); 241 if (*pdeaddr & PG_PS) 242 return pdeaddr; 243 if (*pdeaddr) { 244 return get_ptbase(pmap) + i386_btop(va); 245 } 246 } 247 return (0); 248} 249 250/* 251 * Move the kernel virtual free pointer to the next 252 * 4MB. This is used to help improve performance 253 * by using a large (4MB) page for much of the kernel 254 * (.text, .data, .bss) 255 */ 256static vm_offset_t 257pmap_kmem_choose(vm_offset_t addr) 258{ 259 vm_offset_t newaddr = addr; 260#ifndef DISABLE_PSE 261 if (cpu_feature & CPUID_PSE) { 262 newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 263 } 264#endif 265 return newaddr; 266} 267 268/* 269 * Bootstrap the system enough to run with virtual memory. 270 * 271 * On the i386 this is called after mapping has already been enabled 272 * and just syncs the pmap module with what has already been done. 273 * [We can't call it easily with mapping off since the kernel is not 274 * mapped with PA == VA, hence we would have to relocate every address 275 * from the linked base (virtual) address "KERNBASE" to the actual 276 * (physical) address starting relative to 0] 277 */ 278void 279pmap_bootstrap(firstaddr, loadaddr) 280 vm_offset_t firstaddr; 281 vm_offset_t loadaddr; 282{ 283 vm_offset_t va; 284 pt_entry_t *pte; 285 286 avail_start = firstaddr; 287 288 /* 289 * XXX The calculation of virtual_avail is wrong. It's NKPT*PAGE_SIZE too 290 * large. It should instead be correctly calculated in locore.s and 291 * not based on 'first' (which is a physical address, not a virtual 292 * address, for the start of unused physical memory). The kernel 293 * page tables are NOT double mapped and thus should not be included 294 * in this calculation. 295 */ 296 virtual_avail = (vm_offset_t) KERNBASE + firstaddr; 297 virtual_avail = pmap_kmem_choose(virtual_avail); 298 299 virtual_end = VM_MAX_KERNEL_ADDRESS; 300 301 /* 302 * Initialize protection array. 303 */ 304 i386_protection_init(); 305 306 /* 307 * The kernel's pmap is statically allocated so we don't have to use 308 * pmap_create, which is unlikely to work correctly at this part of 309 * the boot sequence (XXX and which no longer exists). 310 */ 311 kernel_pmap = &kernel_pmap_store; 312 313 kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD); 314 kernel_pmap->pm_count = 1; 315 kernel_pmap->pm_active = -1; /* don't allow deactivation */ 316 TAILQ_INIT(&kernel_pmap->pm_pvlist); 317 LIST_INIT(&allpmaps); 318 LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list); 319 nkpt = NKPT; 320 321 /* 322 * Reserve some special page table entries/VA space for temporary 323 * mapping of pages. 324 */ 325#define SYSMAP(c, p, v, n) \ 326 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n); 327 328 va = virtual_avail; 329 pte = (pt_entry_t *) pmap_pte(kernel_pmap, va); 330 331 /* 332 * CMAP1/CMAP2 are used for zeroing and copying pages. 333 */ 334 SYSMAP(caddr_t, CMAP1, CADDR1, 1) 335 SYSMAP(caddr_t, CMAP2, CADDR2, 1) 336 337 /* 338 * Crashdump maps. 339 */ 340 SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS); 341 342 /* 343 * ptvmmap is used for reading arbitrary physical pages via /dev/mem. 344 * XXX ptmmap is not used. 345 */ 346 SYSMAP(caddr_t, ptmmap, ptvmmap, 1) 347 348 /* 349 * msgbufp is used to map the system message buffer. 350 * XXX msgbufmap is not used. 351 */ 352 SYSMAP(struct msgbuf *, msgbufmap, msgbufp, 353 atop(round_page(MSGBUF_SIZE))) 354 355 /* 356 * ptemap is used for pmap_pte_quick 357 */ 358 SYSMAP(unsigned *, PMAP1, PADDR1, 1); 359 360 virtual_avail = va; 361 362 *(int *) CMAP1 = *(int *) CMAP2 = 0; 363 *(int *) PTD = 0; 364 365 366 pgeflag = 0; 367#if !defined(SMP) /* XXX - see also mp_machdep.c */ 368 if (cpu_feature & CPUID_PGE) { 369 pgeflag = PG_G; 370 } 371#endif 372 373/* 374 * Initialize the 4MB page size flag 375 */ 376 pseflag = 0; 377/* 378 * The 4MB page version of the initial 379 * kernel page mapping. 380 */ 381 pdir4mb = 0; 382 383#if !defined(DISABLE_PSE) 384 if (cpu_feature & CPUID_PSE) { 385 unsigned ptditmp; 386 /* 387 * Note that we have enabled PSE mode 388 */ 389 pseflag = PG_PS; 390 ptditmp = *((unsigned *)PTmap + i386_btop(KERNBASE)); 391 ptditmp &= ~(NBPDR - 1); 392 ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag; 393 pdir4mb = ptditmp; 394 395#if !defined(SMP) 396 /* 397 * Enable the PSE mode. 398 */ 399 load_cr4(rcr4() | CR4_PSE); 400 401 /* 402 * We can do the mapping here for the single processor 403 * case. We simply ignore the old page table page from 404 * now on. 405 */ 406 /* 407 * For SMP, we still need 4K pages to bootstrap APs, 408 * PSE will be enabled as soon as all APs are up. 409 */ 410 PTD[KPTDI] = (pd_entry_t) ptditmp; 411 kernel_pmap->pm_pdir[KPTDI] = (pd_entry_t) ptditmp; 412 invltlb(); 413#endif 414 } 415#endif 416 417#ifdef SMP 418 if (cpu_apic_address == 0) 419 panic("pmap_bootstrap: no local apic! (non-SMP hardware?)"); 420 421 /* local apic is mapped on last page */ 422 SMPpt[NPTEPG - 1] = (pt_entry_t)(PG_V | PG_RW | PG_N | pgeflag | 423 (cpu_apic_address & PG_FRAME)); 424#endif 425 426 invltlb(); 427} 428 429#ifdef SMP 430/* 431 * Set 4mb pdir for mp startup 432 */ 433void 434pmap_set_opt(void) 435{ 436 if (pseflag && (cpu_feature & CPUID_PSE)) { 437 load_cr4(rcr4() | CR4_PSE); 438 if (pdir4mb && PCPU_GET(cpuid) == 0) { /* only on BSP */ 439 kernel_pmap->pm_pdir[KPTDI] = 440 PTD[KPTDI] = (pd_entry_t)pdir4mb; 441 cpu_invltlb(); 442 } 443 } 444} 445#endif 446 447/* 448 * Initialize the pmap module. 449 * Called by vm_init, to initialize any structures that the pmap 450 * system needs to map virtual memory. 451 * pmap_init has been enhanced to support in a fairly consistant 452 * way, discontiguous physical memory. 453 */ 454void 455pmap_init(phys_start, phys_end) 456 vm_offset_t phys_start, phys_end; 457{ 458 int i; 459 int initial_pvs; 460 461 /* 462 * object for kernel page table pages 463 */ 464 kptobj = vm_object_allocate(OBJT_DEFAULT, NKPDE); 465 466 /* 467 * Allocate memory for random pmap data structures. Includes the 468 * pv_head_table. 469 */ 470 471 for(i = 0; i < vm_page_array_size; i++) { 472 vm_page_t m; 473 474 m = &vm_page_array[i]; 475 TAILQ_INIT(&m->md.pv_list); 476 m->md.pv_list_count = 0; 477 } 478 479 /* 480 * init the pv free list 481 */ 482 initial_pvs = vm_page_array_size; 483 if (initial_pvs < MINPV) 484 initial_pvs = MINPV; 485 pvzone = &pvzone_store; 486 pvinit = (struct pv_entry *) kmem_alloc(kernel_map, 487 initial_pvs * sizeof (struct pv_entry)); 488 zbootinit(pvzone, "PV ENTRY", sizeof (struct pv_entry), pvinit, 489 vm_page_array_size); 490 491 /* 492 * Now it is safe to enable pv_table recording. 493 */ 494 pmap_initialized = TRUE; 495} 496 497/* 498 * Initialize the address space (zone) for the pv_entries. Set a 499 * high water mark so that the system can recover from excessive 500 * numbers of pv entries. 501 */ 502void 503pmap_init2() 504{ 505 pv_entry_max = PMAP_SHPGPERPROC * maxproc + vm_page_array_size; 506 pv_entry_high_water = 9 * (pv_entry_max / 10); 507 zinitna(pvzone, &pvzone_obj, NULL, 0, pv_entry_max, ZONE_INTERRUPT, 1); 508} 509 510 511/*************************************************** 512 * Low level helper routines..... 513 ***************************************************/ 514 515#if defined(PMAP_DIAGNOSTIC) 516 517/* 518 * This code checks for non-writeable/modified pages. 519 * This should be an invalid condition. 520 */ 521static int 522pmap_nw_modified(pt_entry_t ptea) 523{ 524 int pte; 525 526 pte = (int) ptea; 527 528 if ((pte & (PG_M|PG_RW)) == PG_M) 529 return 1; 530 else 531 return 0; 532} 533#endif 534 535 536/* 537 * this routine defines the region(s) of memory that should 538 * not be tested for the modified bit. 539 */ 540static PMAP_INLINE int 541pmap_track_modified(vm_offset_t va) 542{ 543 if ((va < clean_sva) || (va >= clean_eva)) 544 return 1; 545 else 546 return 0; 547} 548 549static PMAP_INLINE void 550invltlb_1pg(vm_offset_t va) 551{ 552#ifdef I386_CPU 553 invltlb(); 554#else 555 invlpg(va); 556#endif 557} 558 559static __inline void 560pmap_TLB_invalidate(pmap_t pmap, vm_offset_t va) 561{ 562#if defined(SMP) 563 if (pmap->pm_active & (1 << PCPU_GET(cpuid))) 564 cpu_invlpg((void *)va); 565 if (pmap->pm_active & PCPU_GET(other_cpus)) 566 smp_invltlb(); 567#else 568 if (pmap->pm_active) 569 invltlb_1pg(va); 570#endif 571} 572 573static __inline void 574pmap_TLB_invalidate_all(pmap_t pmap) 575{ 576#if defined(SMP) 577 if (pmap->pm_active & (1 << PCPU_GET(cpuid))) 578 cpu_invltlb(); 579 if (pmap->pm_active & PCPU_GET(other_cpus)) 580 smp_invltlb(); 581#else 582 if (pmap->pm_active) 583 invltlb(); 584#endif 585} 586 587static unsigned * 588get_ptbase(pmap) 589 pmap_t pmap; 590{ 591 unsigned frame = (unsigned) pmap->pm_pdir[PTDPTDI] & PG_FRAME; 592 593 /* are we current address space or kernel? */ 594 if (pmap == kernel_pmap || frame == (((unsigned) PTDpde) & PG_FRAME)) { 595 return (unsigned *) PTmap; 596 } 597 /* otherwise, we are alternate address space */ 598 if (frame != (((unsigned) APTDpde) & PG_FRAME)) { 599 APTDpde = (pd_entry_t) (frame | PG_RW | PG_V); 600#if defined(SMP) 601 /* The page directory is not shared between CPUs */ 602 cpu_invltlb(); 603#else 604 invltlb(); 605#endif 606 } 607 return (unsigned *) APTmap; 608} 609 610/* 611 * Super fast pmap_pte routine best used when scanning 612 * the pv lists. This eliminates many coarse-grained 613 * invltlb calls. Note that many of the pv list 614 * scans are across different pmaps. It is very wasteful 615 * to do an entire invltlb for checking a single mapping. 616 */ 617 618static unsigned * 619pmap_pte_quick(pmap, va) 620 register pmap_t pmap; 621 vm_offset_t va; 622{ 623 unsigned pde, newpf; 624 if ((pde = (unsigned) pmap->pm_pdir[va >> PDRSHIFT]) != 0) { 625 unsigned frame = (unsigned) pmap->pm_pdir[PTDPTDI] & PG_FRAME; 626 unsigned index = i386_btop(va); 627 /* are we current address space or kernel? */ 628 if ((pmap == kernel_pmap) || 629 (frame == (((unsigned) PTDpde) & PG_FRAME))) { 630 return (unsigned *) PTmap + index; 631 } 632 newpf = pde & PG_FRAME; 633 if ( ((* (unsigned *) PMAP1) & PG_FRAME) != newpf) { 634 * (unsigned *) PMAP1 = newpf | PG_RW | PG_V; 635 invltlb_1pg((vm_offset_t) PADDR1); 636 } 637 return PADDR1 + ((unsigned) index & (NPTEPG - 1)); 638 } 639 return (0); 640} 641 642/* 643 * Routine: pmap_extract 644 * Function: 645 * Extract the physical page address associated 646 * with the given map/virtual_address pair. 647 */ 648vm_offset_t 649pmap_extract(pmap, va) 650 register pmap_t pmap; 651 vm_offset_t va; 652{ 653 vm_offset_t rtval; 654 vm_offset_t pdirindex; 655 pdirindex = va >> PDRSHIFT; 656 if (pmap && (rtval = (unsigned) pmap->pm_pdir[pdirindex])) { 657 unsigned *pte; 658 if ((rtval & PG_PS) != 0) { 659 rtval &= ~(NBPDR - 1); 660 rtval |= va & (NBPDR - 1); 661 return rtval; 662 } 663 pte = get_ptbase(pmap) + i386_btop(va); 664 rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); 665 return rtval; 666 } 667 return 0; 668 669} 670 671/*************************************************** 672 * Low level mapping routines..... 673 ***************************************************/ 674 675/* 676 * add a wired page to the kva 677 * note that in order for the mapping to take effect -- you 678 * should do a invltlb after doing the pmap_kenter... 679 */ 680PMAP_INLINE void 681pmap_kenter(va, pa) 682 vm_offset_t va; 683 register vm_offset_t pa; 684{ 685 register unsigned *pte; 686 unsigned npte, opte; 687 688 npte = pa | PG_RW | PG_V | pgeflag; 689 pte = (unsigned *)vtopte(va); 690 opte = *pte; 691 *pte = npte; 692 /*if (opte)*/ 693 invltlb_1pg(va); /* XXX what about SMP? */ 694} 695 696/* 697 * remove a page from the kernel pagetables 698 */ 699PMAP_INLINE void 700pmap_kremove(va) 701 vm_offset_t va; 702{ 703 register unsigned *pte; 704 705 pte = (unsigned *)vtopte(va); 706 *pte = 0; 707 invltlb_1pg(va); /* XXX what about SMP? */ 708} 709 710/* 711 * Used to map a range of physical addresses into kernel 712 * virtual address space. 713 * 714 * The value passed in '*virt' is a suggested virtual address for 715 * the mapping. Architectures which can support a direct-mapped 716 * physical to virtual region can return the appropriate address 717 * within that region, leaving '*virt' unchanged. Other 718 * architectures should map the pages starting at '*virt' and 719 * update '*virt' with the first usable address after the mapped 720 * region. 721 */ 722vm_offset_t 723pmap_map(virt, start, end, prot) 724 vm_offset_t *virt; 725 vm_offset_t start; 726 vm_offset_t end; 727 int prot; 728{ 729 vm_offset_t sva = *virt; 730 vm_offset_t va = sva; 731 while (start < end) { 732 pmap_kenter(va, start); 733 va += PAGE_SIZE; 734 start += PAGE_SIZE; 735 } 736 *virt = va; 737 return (sva); 738} 739 740 741/* 742 * Add a list of wired pages to the kva 743 * this routine is only used for temporary 744 * kernel mappings that do not need to have 745 * page modification or references recorded. 746 * Note that old mappings are simply written 747 * over. The page *must* be wired. 748 */ 749void 750pmap_qenter(va, m, count) 751 vm_offset_t va; 752 vm_page_t *m; 753 int count; 754{ 755 int i; 756 757 for (i = 0; i < count; i++) { 758 vm_offset_t tva = va + i * PAGE_SIZE; 759 pmap_kenter(tva, VM_PAGE_TO_PHYS(m[i])); 760 } 761} 762 763/* 764 * this routine jerks page mappings from the 765 * kernel -- it is meant only for temporary mappings. 766 */ 767void 768pmap_qremove(va, count) 769 vm_offset_t va; 770 int count; 771{ 772 vm_offset_t end_va; 773 774 end_va = va + count*PAGE_SIZE; 775 776 while (va < end_va) { 777 unsigned *pte; 778 779 pte = (unsigned *)vtopte(va); 780 *pte = 0; 781#ifdef SMP 782 cpu_invlpg((void *)va); 783#else 784 invltlb_1pg(va); 785#endif 786 va += PAGE_SIZE; 787 } 788#ifdef SMP 789 smp_invltlb(); 790#endif 791} 792 793static vm_page_t 794pmap_page_lookup(object, pindex) 795 vm_object_t object; 796 vm_pindex_t pindex; 797{ 798 vm_page_t m; 799retry: 800 m = vm_page_lookup(object, pindex); 801 if (m && vm_page_sleep_busy(m, FALSE, "pplookp")) 802 goto retry; 803 return m; 804} 805 806/* 807 * Create the UPAGES for a new process. 808 * This routine directly affects the fork perf for a process. 809 */ 810void 811pmap_new_proc(p) 812 struct proc *p; 813{ 814#ifdef I386_CPU 815 int updateneeded; 816#endif 817 int i; 818 vm_object_t upobj; 819 vm_page_t m; 820 struct user *up; 821 unsigned *ptek, oldpte; 822 823 /* 824 * allocate object for the upages 825 */ 826 if ((upobj = p->p_upages_obj) == NULL) { 827 upobj = vm_object_allocate( OBJT_DEFAULT, UPAGES); 828 p->p_upages_obj = upobj; 829 } 830 831 /* get a kernel virtual address for the UPAGES for this proc */ 832 if ((up = p->p_addr) == NULL) { 833 up = (struct user *) kmem_alloc_nofault(kernel_map, 834 UPAGES * PAGE_SIZE); 835 if (up == NULL) 836 panic("pmap_new_proc: u_map allocation failed"); 837 p->p_addr = up; 838 } 839 840 ptek = (unsigned *) vtopte((vm_offset_t) up); 841 842#ifdef I386_CPU 843 updateneeded = 0; 844#endif 845 for(i=0;i<UPAGES;i++) { 846 /* 847 * Get a kernel stack page 848 */ 849 m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 850 851 /* 852 * Wire the page 853 */ 854 m->wire_count++; 855 cnt.v_wire_count++; 856 857 oldpte = *(ptek + i); 858 /* 859 * Enter the page into the kernel address space. 860 */ 861 *(ptek + i) = VM_PAGE_TO_PHYS(m) | PG_RW | PG_V | pgeflag; 862 if (oldpte) { 863#ifdef I386_CPU 864 updateneeded = 1; 865#else 866 invlpg((vm_offset_t) up + i * PAGE_SIZE); 867#endif 868 } 869 870 vm_page_wakeup(m); 871 vm_page_flag_clear(m, PG_ZERO); 872 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 873 m->valid = VM_PAGE_BITS_ALL; 874 } 875#ifdef I386_CPU 876 if (updateneeded) 877 invltlb(); 878#endif 879} 880 881/* 882 * Dispose the UPAGES for a process that has exited. 883 * This routine directly impacts the exit perf of a process. 884 */ 885void 886pmap_dispose_proc(p) 887 struct proc *p; 888{ 889 int i; 890 vm_object_t upobj; 891 vm_page_t m; 892 unsigned *ptek, oldpte; 893 894 upobj = p->p_upages_obj; 895 896 ptek = (unsigned *) vtopte((vm_offset_t) p->p_addr); 897 for(i=0;i<UPAGES;i++) { 898 899 if ((m = vm_page_lookup(upobj, i)) == NULL) 900 panic("pmap_dispose_proc: upage already missing???"); 901 902 vm_page_busy(m); 903 904 oldpte = *(ptek + i); 905 *(ptek + i) = 0; 906#ifndef I386_CPU 907 invlpg((vm_offset_t) p->p_addr + i * PAGE_SIZE); 908#endif 909 vm_page_unwire(m, 0); 910 vm_page_free(m); 911 } 912#ifdef I386_CPU 913 invltlb(); 914#endif 915} 916 917/* 918 * Allow the UPAGES for a process to be prejudicially paged out. 919 */ 920void 921pmap_swapout_proc(p) 922 struct proc *p; 923{ 924 int i; 925 vm_object_t upobj; 926 vm_page_t m; 927 928 upobj = p->p_upages_obj; 929 /* 930 * let the upages be paged 931 */ 932 for(i=0;i<UPAGES;i++) { 933 if ((m = vm_page_lookup(upobj, i)) == NULL) 934 panic("pmap_swapout_proc: upage already missing???"); 935 vm_page_dirty(m); 936 vm_page_unwire(m, 0); 937 pmap_kremove( (vm_offset_t) p->p_addr + PAGE_SIZE * i); 938 } 939} 940 941/* 942 * Bring the UPAGES for a specified process back in. 943 */ 944void 945pmap_swapin_proc(p) 946 struct proc *p; 947{ 948 int i,rv; 949 vm_object_t upobj; 950 vm_page_t m; 951 952 upobj = p->p_upages_obj; 953 for(i=0;i<UPAGES;i++) { 954 955 m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 956 957 pmap_kenter(((vm_offset_t) p->p_addr) + i * PAGE_SIZE, 958 VM_PAGE_TO_PHYS(m)); 959 960 if (m->valid != VM_PAGE_BITS_ALL) { 961 rv = vm_pager_get_pages(upobj, &m, 1, 0); 962 if (rv != VM_PAGER_OK) 963 panic("pmap_swapin_proc: cannot get upages for proc: %d\n", p->p_pid); 964 m = vm_page_lookup(upobj, i); 965 m->valid = VM_PAGE_BITS_ALL; 966 } 967 968 vm_page_wire(m); 969 vm_page_wakeup(m); 970 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 971 } 972} 973 974/*************************************************** 975 * Page table page management routines..... 976 ***************************************************/ 977 978/* 979 * This routine unholds page table pages, and if the hold count 980 * drops to zero, then it decrements the wire count. 981 */ 982static int 983_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) { 984 985 while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) 986 ; 987 988 if (m->hold_count == 0) { 989 vm_offset_t pteva; 990 /* 991 * unmap the page table page 992 */ 993 pmap->pm_pdir[m->pindex] = 0; 994 --pmap->pm_stats.resident_count; 995 if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) == 996 (((unsigned) PTDpde) & PG_FRAME)) { 997 /* 998 * Do a invltlb to make the invalidated mapping 999 * take effect immediately. 1000 */ 1001 pteva = UPT_MIN_ADDRESS + i386_ptob(m->pindex); 1002 pmap_TLB_invalidate(pmap, pteva); 1003 } 1004 1005 if (pmap->pm_ptphint == m) 1006 pmap->pm_ptphint = NULL; 1007 1008 /* 1009 * If the page is finally unwired, simply free it. 1010 */ 1011 --m->wire_count; 1012 if (m->wire_count == 0) { 1013 1014 vm_page_flash(m); 1015 vm_page_busy(m); 1016 vm_page_free_zero(m); 1017 --cnt.v_wire_count; 1018 } 1019 return 1; 1020 } 1021 return 0; 1022} 1023 1024static PMAP_INLINE int 1025pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1026{ 1027 vm_page_unhold(m); 1028 if (m->hold_count == 0) 1029 return _pmap_unwire_pte_hold(pmap, m); 1030 else 1031 return 0; 1032} 1033 1034/* 1035 * After removing a page table entry, this routine is used to 1036 * conditionally free the page, and manage the hold/wire counts. 1037 */ 1038static int 1039pmap_unuse_pt(pmap, va, mpte) 1040 pmap_t pmap; 1041 vm_offset_t va; 1042 vm_page_t mpte; 1043{ 1044 unsigned ptepindex; 1045 if (va >= UPT_MIN_ADDRESS) 1046 return 0; 1047 1048 if (mpte == NULL) { 1049 ptepindex = (va >> PDRSHIFT); 1050 if (pmap->pm_ptphint && 1051 (pmap->pm_ptphint->pindex == ptepindex)) { 1052 mpte = pmap->pm_ptphint; 1053 } else { 1054 mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex); 1055 pmap->pm_ptphint = mpte; 1056 } 1057 } 1058 1059 return pmap_unwire_pte_hold(pmap, mpte); 1060} 1061 1062void 1063pmap_pinit0(pmap) 1064 struct pmap *pmap; 1065{ 1066 pmap->pm_pdir = 1067 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1068 pmap_kenter((vm_offset_t) pmap->pm_pdir, (vm_offset_t) IdlePTD); 1069 pmap->pm_count = 1; 1070 pmap->pm_active = 0; 1071 pmap->pm_ptphint = NULL; 1072 TAILQ_INIT(&pmap->pm_pvlist); 1073 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1074 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1075} 1076 1077/* 1078 * Initialize a preallocated and zeroed pmap structure, 1079 * such as one in a vmspace structure. 1080 */ 1081void 1082pmap_pinit(pmap) 1083 register struct pmap *pmap; 1084{ 1085 vm_page_t ptdpg; 1086 1087 /* 1088 * No need to allocate page table space yet but we do need a valid 1089 * page directory table. 1090 */ 1091 if (pmap->pm_pdir == NULL) 1092 pmap->pm_pdir = 1093 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1094 1095 /* 1096 * allocate object for the ptes 1097 */ 1098 if (pmap->pm_pteobj == NULL) 1099 pmap->pm_pteobj = vm_object_allocate( OBJT_DEFAULT, PTDPTDI + 1); 1100 1101 /* 1102 * allocate the page directory page 1103 */ 1104 ptdpg = vm_page_grab( pmap->pm_pteobj, PTDPTDI, 1105 VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1106 1107 ptdpg->wire_count = 1; 1108 ++cnt.v_wire_count; 1109 1110 1111 vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/ 1112 ptdpg->valid = VM_PAGE_BITS_ALL; 1113 1114 pmap_kenter((vm_offset_t) pmap->pm_pdir, VM_PAGE_TO_PHYS(ptdpg)); 1115 if ((ptdpg->flags & PG_ZERO) == 0) 1116 bzero(pmap->pm_pdir, PAGE_SIZE); 1117 1118 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1119 /* Wire in kernel global address entries. */ 1120 /* XXX copies current process, does not fill in MPPTDI */ 1121 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1122#ifdef SMP 1123 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1124#endif 1125 1126 /* install self-referential address mapping entry */ 1127 *(unsigned *) (pmap->pm_pdir + PTDPTDI) = 1128 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1129 1130 pmap->pm_count = 1; 1131 pmap->pm_active = 0; 1132 pmap->pm_ptphint = NULL; 1133 TAILQ_INIT(&pmap->pm_pvlist); 1134 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1135} 1136 1137/* 1138 * Wire in kernel global address entries. To avoid a race condition 1139 * between pmap initialization and pmap_growkernel, this procedure 1140 * should be called after the vmspace is attached to the process 1141 * but before this pmap is activated. 1142 */ 1143void 1144pmap_pinit2(pmap) 1145 struct pmap *pmap; 1146{ 1147 /* XXX: Remove this stub when no longer called */ 1148} 1149 1150static int 1151pmap_release_free_page(pmap, p) 1152 struct pmap *pmap; 1153 vm_page_t p; 1154{ 1155 unsigned *pde = (unsigned *) pmap->pm_pdir; 1156 /* 1157 * This code optimizes the case of freeing non-busy 1158 * page-table pages. Those pages are zero now, and 1159 * might as well be placed directly into the zero queue. 1160 */ 1161 if (vm_page_sleep_busy(p, FALSE, "pmaprl")) 1162 return 0; 1163 1164 vm_page_busy(p); 1165 1166 /* 1167 * Remove the page table page from the processes address space. 1168 */ 1169 pde[p->pindex] = 0; 1170 pmap->pm_stats.resident_count--; 1171 1172 if (p->hold_count) { 1173 panic("pmap_release: freeing held page table page"); 1174 } 1175 /* 1176 * Page directory pages need to have the kernel 1177 * stuff cleared, so they can go into the zero queue also. 1178 */ 1179 if (p->pindex == PTDPTDI) { 1180 bzero(pde + KPTDI, nkpt * PTESIZE); 1181#ifdef SMP 1182 pde[MPPTDI] = 0; 1183#endif 1184 pde[APTDPTDI] = 0; 1185 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1186 } 1187 1188 if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex)) 1189 pmap->pm_ptphint = NULL; 1190 1191 p->wire_count--; 1192 cnt.v_wire_count--; 1193 vm_page_free_zero(p); 1194 return 1; 1195} 1196 1197/* 1198 * this routine is called if the page table page is not 1199 * mapped correctly. 1200 */ 1201static vm_page_t 1202_pmap_allocpte(pmap, ptepindex) 1203 pmap_t pmap; 1204 unsigned ptepindex; 1205{ 1206 vm_offset_t pteva, ptepa; 1207 vm_page_t m; 1208 1209 /* 1210 * Find or fabricate a new pagetable page 1211 */ 1212 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1213 VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1214 1215 KASSERT(m->queue == PQ_NONE, 1216 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1217 1218 if (m->wire_count == 0) 1219 cnt.v_wire_count++; 1220 m->wire_count++; 1221 1222 /* 1223 * Increment the hold count for the page table page 1224 * (denoting a new mapping.) 1225 */ 1226 m->hold_count++; 1227 1228 /* 1229 * Map the pagetable page into the process address space, if 1230 * it isn't already there. 1231 */ 1232 1233 pmap->pm_stats.resident_count++; 1234 1235 ptepa = VM_PAGE_TO_PHYS(m); 1236 pmap->pm_pdir[ptepindex] = 1237 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1238 1239 /* 1240 * Set the page table hint 1241 */ 1242 pmap->pm_ptphint = m; 1243 1244 /* 1245 * Try to use the new mapping, but if we cannot, then 1246 * do it with the routine that maps the page explicitly. 1247 */ 1248 if ((m->flags & PG_ZERO) == 0) { 1249 if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) == 1250 (((unsigned) PTDpde) & PG_FRAME)) { 1251 pteva = UPT_MIN_ADDRESS + i386_ptob(ptepindex); 1252 bzero((caddr_t) pteva, PAGE_SIZE); 1253 } else { 1254 pmap_zero_page(ptepa); 1255 } 1256 } 1257 1258 m->valid = VM_PAGE_BITS_ALL; 1259 vm_page_flag_clear(m, PG_ZERO); 1260 vm_page_flag_set(m, PG_MAPPED); 1261 vm_page_wakeup(m); 1262 1263 return m; 1264} 1265 1266static vm_page_t 1267pmap_allocpte(pmap, va) 1268 pmap_t pmap; 1269 vm_offset_t va; 1270{ 1271 unsigned ptepindex; 1272 vm_offset_t ptepa; 1273 vm_page_t m; 1274 1275 /* 1276 * Calculate pagetable page index 1277 */ 1278 ptepindex = va >> PDRSHIFT; 1279 1280 /* 1281 * Get the page directory entry 1282 */ 1283 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1284 1285 /* 1286 * This supports switching from a 4MB page to a 1287 * normal 4K page. 1288 */ 1289 if (ptepa & PG_PS) { 1290 pmap->pm_pdir[ptepindex] = 0; 1291 ptepa = 0; 1292 invltlb(); 1293 } 1294 1295 /* 1296 * If the page table page is mapped, we just increment the 1297 * hold count, and activate it. 1298 */ 1299 if (ptepa) { 1300 /* 1301 * In order to get the page table page, try the 1302 * hint first. 1303 */ 1304 if (pmap->pm_ptphint && 1305 (pmap->pm_ptphint->pindex == ptepindex)) { 1306 m = pmap->pm_ptphint; 1307 } else { 1308 m = pmap_page_lookup( pmap->pm_pteobj, ptepindex); 1309 pmap->pm_ptphint = m; 1310 } 1311 m->hold_count++; 1312 return m; 1313 } 1314 /* 1315 * Here if the pte page isn't mapped, or if it has been deallocated. 1316 */ 1317 return _pmap_allocpte(pmap, ptepindex); 1318} 1319 1320 1321/*************************************************** 1322* Pmap allocation/deallocation routines. 1323 ***************************************************/ 1324 1325/* 1326 * Release any resources held by the given physical map. 1327 * Called when a pmap initialized by pmap_pinit is being released. 1328 * Should only be called if the map contains no valid mappings. 1329 */ 1330void 1331pmap_release(pmap) 1332 register struct pmap *pmap; 1333{ 1334 vm_page_t p,n,ptdpg; 1335 vm_object_t object = pmap->pm_pteobj; 1336 int curgeneration; 1337 1338#if defined(DIAGNOSTIC) 1339 if (object->ref_count != 1) 1340 panic("pmap_release: pteobj reference count != 1"); 1341#endif 1342 1343 ptdpg = NULL; 1344 LIST_REMOVE(pmap, pm_list); 1345retry: 1346 curgeneration = object->generation; 1347 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1348 n = TAILQ_NEXT(p, listq); 1349 if (p->pindex == PTDPTDI) { 1350 ptdpg = p; 1351 continue; 1352 } 1353 while (1) { 1354 if (!pmap_release_free_page(pmap, p) && 1355 (object->generation != curgeneration)) 1356 goto retry; 1357 } 1358 } 1359 1360 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1361 goto retry; 1362} 1363 1364/* 1365 * grow the number of kernel page table entries, if needed 1366 */ 1367void 1368pmap_growkernel(vm_offset_t addr) 1369{ 1370 struct pmap *pmap; 1371 int s; 1372 vm_offset_t ptppaddr; 1373 vm_page_t nkpg; 1374 pd_entry_t newpdir; 1375 1376 s = splhigh(); 1377 if (kernel_vm_end == 0) { 1378 kernel_vm_end = KERNBASE; 1379 nkpt = 0; 1380 while (pdir_pde(PTD, kernel_vm_end)) { 1381 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1382 nkpt++; 1383 } 1384 } 1385 addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1386 while (kernel_vm_end < addr) { 1387 if (pdir_pde(PTD, kernel_vm_end)) { 1388 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1389 continue; 1390 } 1391 1392 /* 1393 * This index is bogus, but out of the way 1394 */ 1395 nkpg = vm_page_alloc(kptobj, nkpt, VM_ALLOC_SYSTEM); 1396 if (!nkpg) 1397 panic("pmap_growkernel: no memory to grow kernel"); 1398 1399 nkpt++; 1400 1401 vm_page_wire(nkpg); 1402 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1403 pmap_zero_page(ptppaddr); 1404 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1405 pdir_pde(PTD, kernel_vm_end) = newpdir; 1406 1407 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1408 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1409 } 1410 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1411 } 1412 splx(s); 1413} 1414 1415/* 1416 * Retire the given physical map from service. 1417 * Should only be called if the map contains 1418 * no valid mappings. 1419 */ 1420void 1421pmap_destroy(pmap) 1422 register pmap_t pmap; 1423{ 1424 int count; 1425 1426 if (pmap == NULL) 1427 return; 1428 1429 count = --pmap->pm_count; 1430 if (count == 0) { 1431 pmap_release(pmap); 1432 panic("destroying a pmap is not yet implemented"); 1433 } 1434} 1435 1436/* 1437 * Add a reference to the specified pmap. 1438 */ 1439void 1440pmap_reference(pmap) 1441 pmap_t pmap; 1442{ 1443 if (pmap != NULL) { 1444 pmap->pm_count++; 1445 } 1446} 1447 1448/*************************************************** 1449* page management routines. 1450 ***************************************************/ 1451 1452/* 1453 * free the pv_entry back to the free list 1454 */ 1455static PMAP_INLINE void 1456free_pv_entry(pv) 1457 pv_entry_t pv; 1458{ 1459 pv_entry_count--; 1460 zfree(pvzone, pv); 1461} 1462 1463/* 1464 * get a new pv_entry, allocating a block from the system 1465 * when needed. 1466 * the memory allocation is performed bypassing the malloc code 1467 * because of the possibility of allocations at interrupt time. 1468 */ 1469static pv_entry_t 1470get_pv_entry(void) 1471{ 1472 pv_entry_count++; 1473 if (pv_entry_high_water && 1474 (pv_entry_count > pv_entry_high_water) && 1475 (pmap_pagedaemon_waken == 0)) { 1476 pmap_pagedaemon_waken = 1; 1477 wakeup (&vm_pages_needed); 1478 } 1479 return zalloc(pvzone); 1480} 1481 1482/* 1483 * This routine is very drastic, but can save the system 1484 * in a pinch. 1485 */ 1486void 1487pmap_collect() 1488{ 1489 int i; 1490 vm_page_t m; 1491 static int warningdone=0; 1492 1493 if (pmap_pagedaemon_waken == 0) 1494 return; 1495 1496 if (warningdone < 5) { 1497 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1498 warningdone++; 1499 } 1500 1501 for(i = 0; i < vm_page_array_size; i++) { 1502 m = &vm_page_array[i]; 1503 if (m->wire_count || m->hold_count || m->busy || 1504 (m->flags & PG_BUSY)) 1505 continue; 1506 pmap_remove_all(m); 1507 } 1508 pmap_pagedaemon_waken = 0; 1509} 1510 1511 1512/* 1513 * If it is the first entry on the list, it is actually 1514 * in the header and we must copy the following entry up 1515 * to the header. Otherwise we must search the list for 1516 * the entry. In either case we free the now unused entry. 1517 */ 1518 1519static int 1520pmap_remove_entry(pmap, m, va) 1521 struct pmap *pmap; 1522 vm_page_t m; 1523 vm_offset_t va; 1524{ 1525 pv_entry_t pv; 1526 int rtval; 1527 int s; 1528 1529 s = splvm(); 1530 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1531 for (pv = TAILQ_FIRST(&m->md.pv_list); 1532 pv; 1533 pv = TAILQ_NEXT(pv, pv_list)) { 1534 if (pmap == pv->pv_pmap && va == pv->pv_va) 1535 break; 1536 } 1537 } else { 1538 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); 1539 pv; 1540 pv = TAILQ_NEXT(pv, pv_plist)) { 1541 if (va == pv->pv_va) 1542 break; 1543 } 1544 } 1545 1546 rtval = 0; 1547 if (pv) { 1548 1549 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1550 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1551 m->md.pv_list_count--; 1552 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1553 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1554 1555 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1556 free_pv_entry(pv); 1557 } 1558 1559 splx(s); 1560 return rtval; 1561} 1562 1563/* 1564 * Create a pv entry for page at pa for 1565 * (pmap, va). 1566 */ 1567static void 1568pmap_insert_entry(pmap, va, mpte, m) 1569 pmap_t pmap; 1570 vm_offset_t va; 1571 vm_page_t mpte; 1572 vm_page_t m; 1573{ 1574 1575 int s; 1576 pv_entry_t pv; 1577 1578 s = splvm(); 1579 pv = get_pv_entry(); 1580 pv->pv_va = va; 1581 pv->pv_pmap = pmap; 1582 pv->pv_ptem = mpte; 1583 1584 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1585 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1586 m->md.pv_list_count++; 1587 1588 splx(s); 1589} 1590 1591/* 1592 * pmap_remove_pte: do the things to unmap a page in a process 1593 */ 1594static int 1595pmap_remove_pte(pmap, ptq, va) 1596 struct pmap *pmap; 1597 unsigned *ptq; 1598 vm_offset_t va; 1599{ 1600 unsigned oldpte; 1601 vm_page_t m; 1602 1603 oldpte = atomic_readandclear_int(ptq); 1604 if (oldpte & PG_W) 1605 pmap->pm_stats.wired_count -= 1; 1606 /* 1607 * Machines that don't support invlpg, also don't support 1608 * PG_G. 1609 */ 1610 if (oldpte & PG_G) 1611 invlpg(va); 1612 pmap->pm_stats.resident_count -= 1; 1613 if (oldpte & PG_MANAGED) { 1614 m = PHYS_TO_VM_PAGE(oldpte); 1615 if (oldpte & PG_M) { 1616#if defined(PMAP_DIAGNOSTIC) 1617 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1618 printf( 1619 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1620 va, oldpte); 1621 } 1622#endif 1623 if (pmap_track_modified(va)) 1624 vm_page_dirty(m); 1625 } 1626 if (oldpte & PG_A) 1627 vm_page_flag_set(m, PG_REFERENCED); 1628 return pmap_remove_entry(pmap, m, va); 1629 } else { 1630 return pmap_unuse_pt(pmap, va, NULL); 1631 } 1632 1633 return 0; 1634} 1635 1636/* 1637 * Remove a single page from a process address space 1638 */ 1639static void 1640pmap_remove_page(pmap, va) 1641 struct pmap *pmap; 1642 register vm_offset_t va; 1643{ 1644 register unsigned *ptq; 1645 1646 /* 1647 * if there is no pte for this address, just skip it!!! 1648 */ 1649 if (*pmap_pde(pmap, va) == 0) { 1650 return; 1651 } 1652 1653 /* 1654 * get a local va for mappings for this pmap. 1655 */ 1656 ptq = get_ptbase(pmap) + i386_btop(va); 1657 if (*ptq) { 1658 (void) pmap_remove_pte(pmap, ptq, va); 1659 pmap_TLB_invalidate(pmap, va); 1660 } 1661 return; 1662} 1663 1664/* 1665 * Remove the given range of addresses from the specified map. 1666 * 1667 * It is assumed that the start and end are properly 1668 * rounded to the page size. 1669 */ 1670void 1671pmap_remove(pmap, sva, eva) 1672 struct pmap *pmap; 1673 register vm_offset_t sva; 1674 register vm_offset_t eva; 1675{ 1676 register unsigned *ptbase; 1677 vm_offset_t pdnxt; 1678 vm_offset_t ptpaddr; 1679 vm_offset_t sindex, eindex; 1680 int anyvalid; 1681 1682 if (pmap == NULL) 1683 return; 1684 1685 if (pmap->pm_stats.resident_count == 0) 1686 return; 1687 1688 /* 1689 * special handling of removing one page. a very 1690 * common operation and easy to short circuit some 1691 * code. 1692 */ 1693 if (((sva + PAGE_SIZE) == eva) && 1694 (((unsigned) pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1695 pmap_remove_page(pmap, sva); 1696 return; 1697 } 1698 1699 anyvalid = 0; 1700 1701 /* 1702 * Get a local virtual address for the mappings that are being 1703 * worked with. 1704 */ 1705 ptbase = get_ptbase(pmap); 1706 1707 sindex = i386_btop(sva); 1708 eindex = i386_btop(eva); 1709 1710 for (; sindex < eindex; sindex = pdnxt) { 1711 unsigned pdirindex; 1712 1713 /* 1714 * Calculate index for next page table. 1715 */ 1716 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1717 if (pmap->pm_stats.resident_count == 0) 1718 break; 1719 1720 pdirindex = sindex / NPDEPG; 1721 if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) { 1722 pmap->pm_pdir[pdirindex] = 0; 1723 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1724 anyvalid++; 1725 continue; 1726 } 1727 1728 /* 1729 * Weed out invalid mappings. Note: we assume that the page 1730 * directory table is always allocated, and in kernel virtual. 1731 */ 1732 if (ptpaddr == 0) 1733 continue; 1734 1735 /* 1736 * Limit our scan to either the end of the va represented 1737 * by the current page table page, or to the end of the 1738 * range being removed. 1739 */ 1740 if (pdnxt > eindex) { 1741 pdnxt = eindex; 1742 } 1743 1744 for ( ;sindex != pdnxt; sindex++) { 1745 vm_offset_t va; 1746 if (ptbase[sindex] == 0) { 1747 continue; 1748 } 1749 va = i386_ptob(sindex); 1750 1751 anyvalid++; 1752 if (pmap_remove_pte(pmap, 1753 ptbase + sindex, va)) 1754 break; 1755 } 1756 } 1757 1758 if (anyvalid) 1759 pmap_TLB_invalidate_all(pmap); 1760} 1761 1762/* 1763 * Routine: pmap_remove_all 1764 * Function: 1765 * Removes this physical page from 1766 * all physical maps in which it resides. 1767 * Reflects back modify bits to the pager. 1768 * 1769 * Notes: 1770 * Original versions of this routine were very 1771 * inefficient because they iteratively called 1772 * pmap_remove (slow...) 1773 */ 1774 1775static void 1776pmap_remove_all(m) 1777 vm_page_t m; 1778{ 1779 register pv_entry_t pv; 1780 register unsigned *pte, tpte; 1781 int s; 1782 1783#if defined(PMAP_DIAGNOSTIC) 1784 /* 1785 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1786 * pages! 1787 */ 1788 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1789 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1790 } 1791#endif 1792 1793 s = splvm(); 1794 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1795 pv->pv_pmap->pm_stats.resident_count--; 1796 1797 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1798 1799 tpte = atomic_readandclear_int(pte); 1800 if (tpte & PG_W) 1801 pv->pv_pmap->pm_stats.wired_count--; 1802 1803 if (tpte & PG_A) 1804 vm_page_flag_set(m, PG_REFERENCED); 1805 1806 /* 1807 * Update the vm_page_t clean and reference bits. 1808 */ 1809 if (tpte & PG_M) { 1810#if defined(PMAP_DIAGNOSTIC) 1811 if (pmap_nw_modified((pt_entry_t) tpte)) { 1812 printf( 1813 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1814 pv->pv_va, tpte); 1815 } 1816#endif 1817 if (pmap_track_modified(pv->pv_va)) 1818 vm_page_dirty(m); 1819 } 1820 pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va); 1821 1822 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1823 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1824 m->md.pv_list_count--; 1825 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1826 free_pv_entry(pv); 1827 } 1828 1829 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1830 1831 splx(s); 1832} 1833 1834/* 1835 * Set the physical protection on the 1836 * specified range of this map as requested. 1837 */ 1838void 1839pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1840{ 1841 register unsigned *ptbase; 1842 vm_offset_t pdnxt, ptpaddr; 1843 vm_pindex_t sindex, eindex; 1844 int anychanged; 1845 1846 if (pmap == NULL) 1847 return; 1848 1849 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1850 pmap_remove(pmap, sva, eva); 1851 return; 1852 } 1853 1854 if (prot & VM_PROT_WRITE) 1855 return; 1856 1857 anychanged = 0; 1858 1859 ptbase = get_ptbase(pmap); 1860 1861 sindex = i386_btop(sva); 1862 eindex = i386_btop(eva); 1863 1864 for (; sindex < eindex; sindex = pdnxt) { 1865 1866 unsigned pdirindex; 1867 1868 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1869 1870 pdirindex = sindex / NPDEPG; 1871 if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) { 1872 (unsigned) pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1873 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1874 anychanged++; 1875 continue; 1876 } 1877 1878 /* 1879 * Weed out invalid mappings. Note: we assume that the page 1880 * directory table is always allocated, and in kernel virtual. 1881 */ 1882 if (ptpaddr == 0) 1883 continue; 1884 1885 if (pdnxt > eindex) { 1886 pdnxt = eindex; 1887 } 1888 1889 for (; sindex != pdnxt; sindex++) { 1890 1891 unsigned pbits; 1892 vm_page_t m; 1893 1894 pbits = ptbase[sindex]; 1895 1896 if (pbits & PG_MANAGED) { 1897 m = NULL; 1898 if (pbits & PG_A) { 1899 m = PHYS_TO_VM_PAGE(pbits); 1900 vm_page_flag_set(m, PG_REFERENCED); 1901 pbits &= ~PG_A; 1902 } 1903 if (pbits & PG_M) { 1904 if (pmap_track_modified(i386_ptob(sindex))) { 1905 if (m == NULL) 1906 m = PHYS_TO_VM_PAGE(pbits); 1907 vm_page_dirty(m); 1908 pbits &= ~PG_M; 1909 } 1910 } 1911 } 1912 1913 pbits &= ~PG_RW; 1914 1915 if (pbits != ptbase[sindex]) { 1916 ptbase[sindex] = pbits; 1917 anychanged = 1; 1918 } 1919 } 1920 } 1921 if (anychanged) 1922 pmap_TLB_invalidate_all(pmap); 1923} 1924 1925/* 1926 * Insert the given physical page (p) at 1927 * the specified virtual address (v) in the 1928 * target physical map with the protection requested. 1929 * 1930 * If specified, the page will be wired down, meaning 1931 * that the related pte can not be reclaimed. 1932 * 1933 * NB: This is the only routine which MAY NOT lazy-evaluate 1934 * or lose information. That is, this routine must actually 1935 * insert this page into the given map NOW. 1936 */ 1937void 1938pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 1939 boolean_t wired) 1940{ 1941 vm_offset_t pa; 1942 register unsigned *pte; 1943 vm_offset_t opa; 1944 vm_offset_t origpte, newpte; 1945 vm_page_t mpte; 1946 1947 if (pmap == NULL) 1948 return; 1949 1950 va &= PG_FRAME; 1951#ifdef PMAP_DIAGNOSTIC 1952 if (va > VM_MAX_KERNEL_ADDRESS) 1953 panic("pmap_enter: toobig"); 1954 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 1955 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 1956#endif 1957 1958 mpte = NULL; 1959 /* 1960 * In the case that a page table page is not 1961 * resident, we are creating it here. 1962 */ 1963 if (va < UPT_MIN_ADDRESS) { 1964 mpte = pmap_allocpte(pmap, va); 1965 } 1966#if 0 && defined(PMAP_DIAGNOSTIC) 1967 else { 1968 vm_offset_t *pdeaddr = (vm_offset_t *)pmap_pde(pmap, va); 1969 if (((origpte = (vm_offset_t) *pdeaddr) & PG_V) == 0) { 1970 panic("pmap_enter: invalid kernel page table page(0), pdir=%p, pde=%p, va=%p\n", 1971 pmap->pm_pdir[PTDPTDI], origpte, va); 1972 } 1973 if (smp_active) { 1974 pdeaddr = (vm_offset_t *) IdlePTDS[PCPU_GET(cpuid)]; 1975 if (((newpte = pdeaddr[va >> PDRSHIFT]) & PG_V) == 0) { 1976 if ((vm_offset_t) my_idlePTD != (vm_offset_t) vtophys(pdeaddr)) 1977 printf("pde mismatch: %x, %x\n", my_idlePTD, pdeaddr); 1978 printf("cpuid: %d, pdeaddr: 0x%x\n", PCPU_GET(cpuid), pdeaddr); 1979 panic("pmap_enter: invalid kernel page table page(1), pdir=%p, npde=%p, pde=%p, va=%p\n", 1980 pmap->pm_pdir[PTDPTDI], newpte, origpte, va); 1981 } 1982 } 1983 } 1984#endif 1985 1986 pte = pmap_pte(pmap, va); 1987 1988 /* 1989 * Page Directory table entry not valid, we need a new PT page 1990 */ 1991 if (pte == NULL) { 1992 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 1993 (void *)pmap->pm_pdir[PTDPTDI], va); 1994 } 1995 1996 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 1997 origpte = *(vm_offset_t *)pte; 1998 opa = origpte & PG_FRAME; 1999 2000 if (origpte & PG_PS) 2001 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2002 2003 /* 2004 * Mapping has not changed, must be protection or wiring change. 2005 */ 2006 if (origpte && (opa == pa)) { 2007 /* 2008 * Wiring change, just update stats. We don't worry about 2009 * wiring PT pages as they remain resident as long as there 2010 * are valid mappings in them. Hence, if a user page is wired, 2011 * the PT page will be also. 2012 */ 2013 if (wired && ((origpte & PG_W) == 0)) 2014 pmap->pm_stats.wired_count++; 2015 else if (!wired && (origpte & PG_W)) 2016 pmap->pm_stats.wired_count--; 2017 2018#if defined(PMAP_DIAGNOSTIC) 2019 if (pmap_nw_modified((pt_entry_t) origpte)) { 2020 printf( 2021 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2022 va, origpte); 2023 } 2024#endif 2025 2026 /* 2027 * Remove extra pte reference 2028 */ 2029 if (mpte) 2030 mpte->hold_count--; 2031 2032 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2033 if ((origpte & PG_RW) == 0) { 2034 *pte |= PG_RW; 2035#ifdef SMP 2036 cpu_invlpg((void *)va); 2037 if (pmap->pm_active & PCPU_GET(other_cpus)) 2038 smp_invltlb(); 2039#else 2040 invltlb_1pg(va); 2041#endif 2042 } 2043 return; 2044 } 2045 2046 /* 2047 * We might be turning off write access to the page, 2048 * so we go ahead and sense modify status. 2049 */ 2050 if (origpte & PG_MANAGED) { 2051 if ((origpte & PG_M) && pmap_track_modified(va)) { 2052 vm_page_t om; 2053 om = PHYS_TO_VM_PAGE(opa); 2054 vm_page_dirty(om); 2055 } 2056 pa |= PG_MANAGED; 2057 } 2058 goto validate; 2059 } 2060 /* 2061 * Mapping has changed, invalidate old range and fall through to 2062 * handle validating new mapping. 2063 */ 2064 if (opa) { 2065 int err; 2066 err = pmap_remove_pte(pmap, pte, va); 2067 if (err) 2068 panic("pmap_enter: pte vanished, va: 0x%x", va); 2069 } 2070 2071 /* 2072 * Enter on the PV list if part of our managed memory. Note that we 2073 * raise IPL while manipulating pv_table since pmap_enter can be 2074 * called at interrupt time. 2075 */ 2076 if (pmap_initialized && 2077 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2078 pmap_insert_entry(pmap, va, mpte, m); 2079 pa |= PG_MANAGED; 2080 } 2081 2082 /* 2083 * Increment counters 2084 */ 2085 pmap->pm_stats.resident_count++; 2086 if (wired) 2087 pmap->pm_stats.wired_count++; 2088 2089validate: 2090 /* 2091 * Now validate mapping with desired protection/wiring. 2092 */ 2093 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2094 2095 if (wired) 2096 newpte |= PG_W; 2097 if (va < UPT_MIN_ADDRESS) 2098 newpte |= PG_U; 2099 if (pmap == kernel_pmap) 2100 newpte |= pgeflag; 2101 2102 /* 2103 * if the mapping or permission bits are different, we need 2104 * to update the pte. 2105 */ 2106 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2107 *pte = newpte | PG_A; 2108 /*if (origpte)*/ { 2109#ifdef SMP 2110 cpu_invlpg((void *)va); 2111 if (pmap->pm_active & PCPU_GET(other_cpus)) 2112 smp_invltlb(); 2113#else 2114 invltlb_1pg(va); 2115#endif 2116 } 2117 } 2118} 2119 2120/* 2121 * this code makes some *MAJOR* assumptions: 2122 * 1. Current pmap & pmap exists. 2123 * 2. Not wired. 2124 * 3. Read access. 2125 * 4. No page table pages. 2126 * 5. Tlbflush is deferred to calling procedure. 2127 * 6. Page IS managed. 2128 * but is *MUCH* faster than pmap_enter... 2129 */ 2130 2131static vm_page_t 2132pmap_enter_quick(pmap, va, m, mpte) 2133 register pmap_t pmap; 2134 vm_offset_t va; 2135 vm_page_t m; 2136 vm_page_t mpte; 2137{ 2138 unsigned *pte; 2139 vm_offset_t pa; 2140 2141 /* 2142 * In the case that a page table page is not 2143 * resident, we are creating it here. 2144 */ 2145 if (va < UPT_MIN_ADDRESS) { 2146 unsigned ptepindex; 2147 vm_offset_t ptepa; 2148 2149 /* 2150 * Calculate pagetable page index 2151 */ 2152 ptepindex = va >> PDRSHIFT; 2153 if (mpte && (mpte->pindex == ptepindex)) { 2154 mpte->hold_count++; 2155 } else { 2156retry: 2157 /* 2158 * Get the page directory entry 2159 */ 2160 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 2161 2162 /* 2163 * If the page table page is mapped, we just increment 2164 * the hold count, and activate it. 2165 */ 2166 if (ptepa) { 2167 if (ptepa & PG_PS) 2168 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2169 if (pmap->pm_ptphint && 2170 (pmap->pm_ptphint->pindex == ptepindex)) { 2171 mpte = pmap->pm_ptphint; 2172 } else { 2173 mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex); 2174 pmap->pm_ptphint = mpte; 2175 } 2176 if (mpte == NULL) 2177 goto retry; 2178 mpte->hold_count++; 2179 } else { 2180 mpte = _pmap_allocpte(pmap, ptepindex); 2181 } 2182 } 2183 } else { 2184 mpte = NULL; 2185 } 2186 2187 /* 2188 * This call to vtopte makes the assumption that we are 2189 * entering the page into the current pmap. In order to support 2190 * quick entry into any pmap, one would likely use pmap_pte_quick. 2191 * But that isn't as quick as vtopte. 2192 */ 2193 pte = (unsigned *)vtopte(va); 2194 if (*pte) { 2195 if (mpte) 2196 pmap_unwire_pte_hold(pmap, mpte); 2197 return 0; 2198 } 2199 2200 /* 2201 * Enter on the PV list if part of our managed memory. Note that we 2202 * raise IPL while manipulating pv_table since pmap_enter can be 2203 * called at interrupt time. 2204 */ 2205 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2206 pmap_insert_entry(pmap, va, mpte, m); 2207 2208 /* 2209 * Increment counters 2210 */ 2211 pmap->pm_stats.resident_count++; 2212 2213 pa = VM_PAGE_TO_PHYS(m); 2214 2215 /* 2216 * Now validate mapping with RO protection 2217 */ 2218 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2219 *pte = pa | PG_V | PG_U; 2220 else 2221 *pte = pa | PG_V | PG_U | PG_MANAGED; 2222 2223 return mpte; 2224} 2225 2226/* 2227 * Make a temporary mapping for a physical address. This is only intended 2228 * to be used for panic dumps. 2229 */ 2230void * 2231pmap_kenter_temporary(vm_offset_t pa, int i) 2232{ 2233 pmap_kenter((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa); 2234 return ((void *)crashdumpmap); 2235} 2236 2237#define MAX_INIT_PT (96) 2238/* 2239 * pmap_object_init_pt preloads the ptes for a given object 2240 * into the specified pmap. This eliminates the blast of soft 2241 * faults on process startup and immediately after an mmap. 2242 */ 2243void 2244pmap_object_init_pt(pmap, addr, object, pindex, size, limit) 2245 pmap_t pmap; 2246 vm_offset_t addr; 2247 vm_object_t object; 2248 vm_pindex_t pindex; 2249 vm_size_t size; 2250 int limit; 2251{ 2252 vm_offset_t tmpidx; 2253 int psize; 2254 vm_page_t p, mpte; 2255 int objpgs; 2256 2257 if (pmap == NULL || object == NULL) 2258 return; 2259 2260 /* 2261 * This code maps large physical mmap regions into the 2262 * processor address space. Note that some shortcuts 2263 * are taken, but the code works. 2264 */ 2265 if (pseflag && 2266 (object->type == OBJT_DEVICE) && 2267 ((addr & (NBPDR - 1)) == 0) && 2268 ((size & (NBPDR - 1)) == 0) ) { 2269 int i; 2270 vm_page_t m[1]; 2271 unsigned int ptepindex; 2272 int npdes; 2273 vm_offset_t ptepa; 2274 2275 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2276 return; 2277 2278retry: 2279 p = vm_page_lookup(object, pindex); 2280 if (p && vm_page_sleep_busy(p, FALSE, "init4p")) 2281 goto retry; 2282 2283 if (p == NULL) { 2284 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2285 if (p == NULL) 2286 return; 2287 m[0] = p; 2288 2289 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2290 vm_page_free(p); 2291 return; 2292 } 2293 2294 p = vm_page_lookup(object, pindex); 2295 vm_page_wakeup(p); 2296 } 2297 2298 ptepa = (vm_offset_t) VM_PAGE_TO_PHYS(p); 2299 if (ptepa & (NBPDR - 1)) { 2300 return; 2301 } 2302 2303 p->valid = VM_PAGE_BITS_ALL; 2304 2305 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2306 npdes = size >> PDRSHIFT; 2307 for(i=0;i<npdes;i++) { 2308 pmap->pm_pdir[ptepindex] = 2309 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_PS); 2310 ptepa += NBPDR; 2311 ptepindex += 1; 2312 } 2313 vm_page_flag_set(p, PG_MAPPED); 2314 invltlb(); 2315 return; 2316 } 2317 2318 psize = i386_btop(size); 2319 2320 if ((object->type != OBJT_VNODE) || 2321 (limit && (psize > MAX_INIT_PT) && 2322 (object->resident_page_count > MAX_INIT_PT))) { 2323 return; 2324 } 2325 2326 if (psize + pindex > object->size) { 2327 if (object->size < pindex) 2328 return; 2329 psize = object->size - pindex; 2330 } 2331 2332 mpte = NULL; 2333 /* 2334 * if we are processing a major portion of the object, then scan the 2335 * entire thing. 2336 */ 2337 if (psize > (object->resident_page_count >> 2)) { 2338 objpgs = psize; 2339 2340 for (p = TAILQ_FIRST(&object->memq); 2341 ((objpgs > 0) && (p != NULL)); 2342 p = TAILQ_NEXT(p, listq)) { 2343 2344 tmpidx = p->pindex; 2345 if (tmpidx < pindex) { 2346 continue; 2347 } 2348 tmpidx -= pindex; 2349 if (tmpidx >= psize) { 2350 continue; 2351 } 2352 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2353 (p->busy == 0) && 2354 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2355 if ((p->queue - p->pc) == PQ_CACHE) 2356 vm_page_deactivate(p); 2357 vm_page_busy(p); 2358 mpte = pmap_enter_quick(pmap, 2359 addr + i386_ptob(tmpidx), p, mpte); 2360 vm_page_flag_set(p, PG_MAPPED); 2361 vm_page_wakeup(p); 2362 } 2363 objpgs -= 1; 2364 } 2365 } else { 2366 /* 2367 * else lookup the pages one-by-one. 2368 */ 2369 for (tmpidx = 0; tmpidx < psize; tmpidx += 1) { 2370 p = vm_page_lookup(object, tmpidx + pindex); 2371 if (p && 2372 ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2373 (p->busy == 0) && 2374 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2375 if ((p->queue - p->pc) == PQ_CACHE) 2376 vm_page_deactivate(p); 2377 vm_page_busy(p); 2378 mpte = pmap_enter_quick(pmap, 2379 addr + i386_ptob(tmpidx), p, mpte); 2380 vm_page_flag_set(p, PG_MAPPED); 2381 vm_page_wakeup(p); 2382 } 2383 } 2384 } 2385 return; 2386} 2387 2388/* 2389 * pmap_prefault provides a quick way of clustering 2390 * pagefaults into a processes address space. It is a "cousin" 2391 * of pmap_object_init_pt, except it runs at page fault time instead 2392 * of mmap time. 2393 */ 2394#define PFBAK 4 2395#define PFFOR 4 2396#define PAGEORDER_SIZE (PFBAK+PFFOR) 2397 2398static int pmap_prefault_pageorder[] = { 2399 -PAGE_SIZE, PAGE_SIZE, 2400 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2401 -3 * PAGE_SIZE, 3 * PAGE_SIZE 2402 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2403}; 2404 2405void 2406pmap_prefault(pmap, addra, entry) 2407 pmap_t pmap; 2408 vm_offset_t addra; 2409 vm_map_entry_t entry; 2410{ 2411 int i; 2412 vm_offset_t starta; 2413 vm_offset_t addr; 2414 vm_pindex_t pindex; 2415 vm_page_t m, mpte; 2416 vm_object_t object; 2417 2418 if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace))) 2419 return; 2420 2421 object = entry->object.vm_object; 2422 2423 starta = addra - PFBAK * PAGE_SIZE; 2424 if (starta < entry->start) { 2425 starta = entry->start; 2426 } else if (starta > addra) { 2427 starta = 0; 2428 } 2429 2430 mpte = NULL; 2431 for (i = 0; i < PAGEORDER_SIZE; i++) { 2432 vm_object_t lobject; 2433 unsigned *pte; 2434 2435 addr = addra + pmap_prefault_pageorder[i]; 2436 if (addr > addra + (PFFOR * PAGE_SIZE)) 2437 addr = 0; 2438 2439 if (addr < starta || addr >= entry->end) 2440 continue; 2441 2442 if ((*pmap_pde(pmap, addr)) == NULL) 2443 continue; 2444 2445 pte = (unsigned *) vtopte(addr); 2446 if (*pte) 2447 continue; 2448 2449 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2450 lobject = object; 2451 for (m = vm_page_lookup(lobject, pindex); 2452 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2453 lobject = lobject->backing_object) { 2454 if (lobject->backing_object_offset & PAGE_MASK) 2455 break; 2456 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2457 m = vm_page_lookup(lobject->backing_object, pindex); 2458 } 2459 2460 /* 2461 * give-up when a page is not in memory 2462 */ 2463 if (m == NULL) 2464 break; 2465 2466 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2467 (m->busy == 0) && 2468 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2469 2470 if ((m->queue - m->pc) == PQ_CACHE) { 2471 vm_page_deactivate(m); 2472 } 2473 vm_page_busy(m); 2474 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2475 vm_page_flag_set(m, PG_MAPPED); 2476 vm_page_wakeup(m); 2477 } 2478 } 2479} 2480 2481/* 2482 * Routine: pmap_change_wiring 2483 * Function: Change the wiring attribute for a map/virtual-address 2484 * pair. 2485 * In/out conditions: 2486 * The mapping must already exist in the pmap. 2487 */ 2488void 2489pmap_change_wiring(pmap, va, wired) 2490 register pmap_t pmap; 2491 vm_offset_t va; 2492 boolean_t wired; 2493{ 2494 register unsigned *pte; 2495 2496 if (pmap == NULL) 2497 return; 2498 2499 pte = pmap_pte(pmap, va); 2500 2501 if (wired && !pmap_pte_w(pte)) 2502 pmap->pm_stats.wired_count++; 2503 else if (!wired && pmap_pte_w(pte)) 2504 pmap->pm_stats.wired_count--; 2505 2506 /* 2507 * Wiring is not a hardware characteristic so there is no need to 2508 * invalidate TLB. 2509 */ 2510 pmap_pte_set_w(pte, wired); 2511} 2512 2513 2514 2515/* 2516 * Copy the range specified by src_addr/len 2517 * from the source map to the range dst_addr/len 2518 * in the destination map. 2519 * 2520 * This routine is only advisory and need not do anything. 2521 */ 2522 2523void 2524pmap_copy(dst_pmap, src_pmap, dst_addr, len, src_addr) 2525 pmap_t dst_pmap, src_pmap; 2526 vm_offset_t dst_addr; 2527 vm_size_t len; 2528 vm_offset_t src_addr; 2529{ 2530 vm_offset_t addr; 2531 vm_offset_t end_addr = src_addr + len; 2532 vm_offset_t pdnxt; 2533 unsigned src_frame, dst_frame; 2534 vm_page_t m; 2535 2536 if (dst_addr != src_addr) 2537 return; 2538 2539 src_frame = ((unsigned) src_pmap->pm_pdir[PTDPTDI]) & PG_FRAME; 2540 if (src_frame != (((unsigned) PTDpde) & PG_FRAME)) { 2541 return; 2542 } 2543 2544 dst_frame = ((unsigned) dst_pmap->pm_pdir[PTDPTDI]) & PG_FRAME; 2545 if (dst_frame != (((unsigned) APTDpde) & PG_FRAME)) { 2546 APTDpde = (pd_entry_t) (dst_frame | PG_RW | PG_V); 2547#if defined(SMP) 2548 /* The page directory is not shared between CPUs */ 2549 cpu_invltlb(); 2550#else 2551 invltlb(); 2552#endif 2553 } 2554 2555 for(addr = src_addr; addr < end_addr; addr = pdnxt) { 2556 unsigned *src_pte, *dst_pte; 2557 vm_page_t dstmpte, srcmpte; 2558 vm_offset_t srcptepaddr; 2559 unsigned ptepindex; 2560 2561 if (addr >= UPT_MIN_ADDRESS) 2562 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2563 2564 /* 2565 * Don't let optional prefaulting of pages make us go 2566 * way below the low water mark of free pages or way 2567 * above high water mark of used pv entries. 2568 */ 2569 if (cnt.v_free_count < cnt.v_free_reserved || 2570 pv_entry_count > pv_entry_high_water) 2571 break; 2572 2573 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2574 ptepindex = addr >> PDRSHIFT; 2575 2576 srcptepaddr = (vm_offset_t) src_pmap->pm_pdir[ptepindex]; 2577 if (srcptepaddr == 0) 2578 continue; 2579 2580 if (srcptepaddr & PG_PS) { 2581 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2582 dst_pmap->pm_pdir[ptepindex] = (pd_entry_t) srcptepaddr; 2583 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2584 } 2585 continue; 2586 } 2587 2588 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2589 if ((srcmpte == NULL) || 2590 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2591 continue; 2592 2593 if (pdnxt > end_addr) 2594 pdnxt = end_addr; 2595 2596 src_pte = (unsigned *) vtopte(addr); 2597 dst_pte = (unsigned *) avtopte(addr); 2598 while (addr < pdnxt) { 2599 unsigned ptetemp; 2600 ptetemp = *src_pte; 2601 /* 2602 * we only virtual copy managed pages 2603 */ 2604 if ((ptetemp & PG_MANAGED) != 0) { 2605 /* 2606 * We have to check after allocpte for the 2607 * pte still being around... allocpte can 2608 * block. 2609 */ 2610 dstmpte = pmap_allocpte(dst_pmap, addr); 2611 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2612 /* 2613 * Clear the modified and 2614 * accessed (referenced) bits 2615 * during the copy. 2616 */ 2617 m = PHYS_TO_VM_PAGE(ptetemp); 2618 *dst_pte = ptetemp & ~(PG_M | PG_A); 2619 dst_pmap->pm_stats.resident_count++; 2620 pmap_insert_entry(dst_pmap, addr, 2621 dstmpte, m); 2622 } else { 2623 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2624 } 2625 if (dstmpte->hold_count >= srcmpte->hold_count) 2626 break; 2627 } 2628 addr += PAGE_SIZE; 2629 src_pte++; 2630 dst_pte++; 2631 } 2632 } 2633} 2634 2635/* 2636 * Routine: pmap_kernel 2637 * Function: 2638 * Returns the physical map handle for the kernel. 2639 */ 2640pmap_t 2641pmap_kernel() 2642{ 2643 return (kernel_pmap); 2644} 2645 2646/* 2647 * pmap_zero_page zeros the specified hardware page by mapping 2648 * the page into KVM and using bzero to clear its contents. 2649 */ 2650void 2651pmap_zero_page(phys) 2652 vm_offset_t phys; 2653{ 2654 2655 if (*(int *) CMAP2) 2656 panic("pmap_zero_page: CMAP2 busy"); 2657 2658 *(int *) CMAP2 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M; 2659 invltlb_1pg((vm_offset_t)CADDR2); 2660 2661#if defined(I686_CPU) 2662 if (cpu_class == CPUCLASS_686) 2663 i686_pagezero(CADDR2); 2664 else 2665#endif 2666 bzero(CADDR2, PAGE_SIZE); 2667 *(int *) CMAP2 = 0; 2668} 2669 2670/* 2671 * pmap_zero_page_area zeros the specified hardware page by mapping 2672 * the page into KVM and using bzero to clear its contents. 2673 * 2674 * off and size may not cover an area beyond a single hardware page. 2675 */ 2676void 2677pmap_zero_page_area(phys, off, size) 2678 vm_offset_t phys; 2679 int off; 2680 int size; 2681{ 2682 2683 if (*(int *) CMAP2) 2684 panic("pmap_zero_page: CMAP2 busy"); 2685 2686 *(int *) CMAP2 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M; 2687 invltlb_1pg((vm_offset_t)CADDR2); 2688 2689#if defined(I686_CPU) 2690 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2691 i686_pagezero(CADDR2); 2692 else 2693#endif 2694 bzero((char *)CADDR2 + off, size); 2695 *(int *) CMAP2 = 0; 2696} 2697 2698/* 2699 * pmap_copy_page copies the specified (machine independent) 2700 * page by mapping the page into virtual memory and using 2701 * bcopy to copy the page, one machine dependent page at a 2702 * time. 2703 */ 2704void 2705pmap_copy_page(src, dst) 2706 vm_offset_t src; 2707 vm_offset_t dst; 2708{ 2709 2710 if (*(int *) CMAP1) 2711 panic("pmap_copy_page: CMAP1 busy"); 2712 if (*(int *) CMAP2) 2713 panic("pmap_copy_page: CMAP2 busy"); 2714 2715 *(int *) CMAP1 = PG_V | (src & PG_FRAME) | PG_A; 2716 *(int *) CMAP2 = PG_V | PG_RW | (dst & PG_FRAME) | PG_A | PG_M; 2717#ifdef I386_CPU 2718 invltlb(); 2719#else 2720 invlpg((u_int)CADDR1); 2721 invlpg((u_int)CADDR2); 2722#endif 2723 2724 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2725 2726 *(int *) CMAP1 = 0; 2727 *(int *) CMAP2 = 0; 2728} 2729 2730 2731/* 2732 * Routine: pmap_pageable 2733 * Function: 2734 * Make the specified pages (by pmap, offset) 2735 * pageable (or not) as requested. 2736 * 2737 * A page which is not pageable may not take 2738 * a fault; therefore, its page table entry 2739 * must remain valid for the duration. 2740 * 2741 * This routine is merely advisory; pmap_enter 2742 * will specify that these pages are to be wired 2743 * down (or not) as appropriate. 2744 */ 2745void 2746pmap_pageable(pmap, sva, eva, pageable) 2747 pmap_t pmap; 2748 vm_offset_t sva, eva; 2749 boolean_t pageable; 2750{ 2751} 2752 2753/* 2754 * this routine returns true if a physical page resides 2755 * in the given pmap. 2756 */ 2757boolean_t 2758pmap_page_exists(pmap, m) 2759 pmap_t pmap; 2760 vm_page_t m; 2761{ 2762 register pv_entry_t pv; 2763 int s; 2764 2765 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2766 return FALSE; 2767 2768 s = splvm(); 2769 2770 /* 2771 * Not found, check current mappings returning immediately if found. 2772 */ 2773 for (pv = TAILQ_FIRST(&m->md.pv_list); 2774 pv; 2775 pv = TAILQ_NEXT(pv, pv_list)) { 2776 if (pv->pv_pmap == pmap) { 2777 splx(s); 2778 return TRUE; 2779 } 2780 } 2781 splx(s); 2782 return (FALSE); 2783} 2784 2785#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2786/* 2787 * Remove all pages from specified address space 2788 * this aids process exit speeds. Also, this code 2789 * is special cased for current process only, but 2790 * can have the more generic (and slightly slower) 2791 * mode enabled. This is much faster than pmap_remove 2792 * in the case of running down an entire address space. 2793 */ 2794void 2795pmap_remove_pages(pmap, sva, eva) 2796 pmap_t pmap; 2797 vm_offset_t sva, eva; 2798{ 2799 unsigned *pte, tpte; 2800 pv_entry_t pv, npv; 2801 int s; 2802 vm_page_t m; 2803 2804#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2805 if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace))) { 2806 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2807 return; 2808 } 2809#endif 2810 2811 s = splvm(); 2812 for(pv = TAILQ_FIRST(&pmap->pm_pvlist); 2813 pv; 2814 pv = npv) { 2815 2816 if (pv->pv_va >= eva || pv->pv_va < sva) { 2817 npv = TAILQ_NEXT(pv, pv_plist); 2818 continue; 2819 } 2820 2821#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2822 pte = (unsigned *)vtopte(pv->pv_va); 2823#else 2824 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2825#endif 2826 tpte = *pte; 2827 2828/* 2829 * We cannot remove wired pages from a process' mapping at this time 2830 */ 2831 if (tpte & PG_W) { 2832 npv = TAILQ_NEXT(pv, pv_plist); 2833 continue; 2834 } 2835 *pte = 0; 2836 2837 m = PHYS_TO_VM_PAGE(tpte); 2838 2839 KASSERT(m < &vm_page_array[vm_page_array_size], 2840 ("pmap_remove_pages: bad tpte %x", tpte)); 2841 2842 pv->pv_pmap->pm_stats.resident_count--; 2843 2844 /* 2845 * Update the vm_page_t clean and reference bits. 2846 */ 2847 if (tpte & PG_M) { 2848 vm_page_dirty(m); 2849 } 2850 2851 2852 npv = TAILQ_NEXT(pv, pv_plist); 2853 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 2854 2855 m->md.pv_list_count--; 2856 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 2857 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 2858 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 2859 } 2860 2861 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 2862 free_pv_entry(pv); 2863 } 2864 splx(s); 2865 pmap_TLB_invalidate_all(pmap); 2866} 2867 2868/* 2869 * pmap_testbit tests bits in pte's 2870 * note that the testbit/changebit routines are inline, 2871 * and a lot of things compile-time evaluate. 2872 */ 2873static boolean_t 2874pmap_testbit(m, bit) 2875 vm_page_t m; 2876 int bit; 2877{ 2878 pv_entry_t pv; 2879 unsigned *pte; 2880 int s; 2881 2882 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2883 return FALSE; 2884 2885 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 2886 return FALSE; 2887 2888 s = splvm(); 2889 2890 for (pv = TAILQ_FIRST(&m->md.pv_list); 2891 pv; 2892 pv = TAILQ_NEXT(pv, pv_list)) { 2893 2894 /* 2895 * if the bit being tested is the modified bit, then 2896 * mark clean_map and ptes as never 2897 * modified. 2898 */ 2899 if (bit & (PG_A|PG_M)) { 2900 if (!pmap_track_modified(pv->pv_va)) 2901 continue; 2902 } 2903 2904#if defined(PMAP_DIAGNOSTIC) 2905 if (!pv->pv_pmap) { 2906 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 2907 continue; 2908 } 2909#endif 2910 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2911 if (*pte & bit) { 2912 splx(s); 2913 return TRUE; 2914 } 2915 } 2916 splx(s); 2917 return (FALSE); 2918} 2919 2920/* 2921 * this routine is used to modify bits in ptes 2922 */ 2923static __inline void 2924pmap_changebit(m, bit, setem) 2925 vm_page_t m; 2926 int bit; 2927 boolean_t setem; 2928{ 2929 register pv_entry_t pv; 2930 register unsigned *pte; 2931 int s; 2932 2933 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2934 return; 2935 2936 s = splvm(); 2937 2938 /* 2939 * Loop over all current mappings setting/clearing as appropos If 2940 * setting RO do we need to clear the VAC? 2941 */ 2942 for (pv = TAILQ_FIRST(&m->md.pv_list); 2943 pv; 2944 pv = TAILQ_NEXT(pv, pv_list)) { 2945 2946 /* 2947 * don't write protect pager mappings 2948 */ 2949 if (!setem && (bit == PG_RW)) { 2950 if (!pmap_track_modified(pv->pv_va)) 2951 continue; 2952 } 2953 2954#if defined(PMAP_DIAGNOSTIC) 2955 if (!pv->pv_pmap) { 2956 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 2957 continue; 2958 } 2959#endif 2960 2961 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2962 2963 if (setem) { 2964 *(int *)pte |= bit; 2965 pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va); 2966 } else { 2967 vm_offset_t pbits = *(vm_offset_t *)pte; 2968 if (pbits & bit) { 2969 if (bit == PG_RW) { 2970 if (pbits & PG_M) { 2971 vm_page_dirty(m); 2972 } 2973 *(int *)pte = pbits & ~(PG_M|PG_RW); 2974 } else { 2975 *(int *)pte = pbits & ~bit; 2976 } 2977 pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va); 2978 } 2979 } 2980 } 2981 splx(s); 2982} 2983 2984/* 2985 * pmap_page_protect: 2986 * 2987 * Lower the permission for all mappings to a given page. 2988 */ 2989void 2990pmap_page_protect(vm_page_t m, vm_prot_t prot) 2991{ 2992 if ((prot & VM_PROT_WRITE) == 0) { 2993 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 2994 pmap_changebit(m, PG_RW, FALSE); 2995 } else { 2996 pmap_remove_all(m); 2997 } 2998 } 2999} 3000 3001vm_offset_t 3002pmap_phys_address(ppn) 3003 int ppn; 3004{ 3005 return (i386_ptob(ppn)); 3006} 3007 3008/* 3009 * pmap_ts_referenced: 3010 * 3011 * Return the count of reference bits for a page, clearing all of them. 3012 */ 3013int 3014pmap_ts_referenced(vm_page_t m) 3015{ 3016 register pv_entry_t pv, pvf, pvn; 3017 unsigned *pte; 3018 int s; 3019 int rtval = 0; 3020 3021 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3022 return (rtval); 3023 3024 s = splvm(); 3025 3026 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3027 3028 pvf = pv; 3029 3030 do { 3031 pvn = TAILQ_NEXT(pv, pv_list); 3032 3033 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3034 3035 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3036 3037 if (!pmap_track_modified(pv->pv_va)) 3038 continue; 3039 3040 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3041 3042 if (pte && (*pte & PG_A)) { 3043 *pte &= ~PG_A; 3044 3045 pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va); 3046 3047 rtval++; 3048 if (rtval > 4) { 3049 break; 3050 } 3051 } 3052 } while ((pv = pvn) != NULL && pv != pvf); 3053 } 3054 splx(s); 3055 3056 return (rtval); 3057} 3058 3059/* 3060 * pmap_is_modified: 3061 * 3062 * Return whether or not the specified physical page was modified 3063 * in any physical maps. 3064 */ 3065boolean_t 3066pmap_is_modified(vm_page_t m) 3067{ 3068 return pmap_testbit(m, PG_M); 3069} 3070 3071/* 3072 * Clear the modify bits on the specified physical page. 3073 */ 3074void 3075pmap_clear_modify(vm_page_t m) 3076{ 3077 pmap_changebit(m, PG_M, FALSE); 3078} 3079 3080/* 3081 * pmap_clear_reference: 3082 * 3083 * Clear the reference bit on the specified physical page. 3084 */ 3085void 3086pmap_clear_reference(vm_page_t m) 3087{ 3088 pmap_changebit(m, PG_A, FALSE); 3089} 3090 3091/* 3092 * Miscellaneous support routines follow 3093 */ 3094 3095static void 3096i386_protection_init() 3097{ 3098 register int *kp, prot; 3099 3100 kp = protection_codes; 3101 for (prot = 0; prot < 8; prot++) { 3102 switch (prot) { 3103 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3104 /* 3105 * Read access is also 0. There isn't any execute bit, 3106 * so just make it readable. 3107 */ 3108 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3109 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3110 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3111 *kp++ = 0; 3112 break; 3113 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3114 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3115 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3116 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3117 *kp++ = PG_RW; 3118 break; 3119 } 3120 } 3121} 3122 3123/* 3124 * Map a set of physical memory pages into the kernel virtual 3125 * address space. Return a pointer to where it is mapped. This 3126 * routine is intended to be used for mapping device memory, 3127 * NOT real memory. 3128 */ 3129void * 3130pmap_mapdev(pa, size) 3131 vm_offset_t pa; 3132 vm_size_t size; 3133{ 3134 vm_offset_t va, tmpva, offset; 3135 unsigned *pte; 3136 3137 offset = pa & PAGE_MASK; 3138 size = roundup(offset + size, PAGE_SIZE); 3139 3140 va = kmem_alloc_pageable(kernel_map, size); 3141 if (!va) 3142 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3143 3144 pa = pa & PG_FRAME; 3145 for (tmpva = va; size > 0;) { 3146 pte = (unsigned *)vtopte(tmpva); 3147 *pte = pa | PG_RW | PG_V | pgeflag; 3148 size -= PAGE_SIZE; 3149 tmpva += PAGE_SIZE; 3150 pa += PAGE_SIZE; 3151 } 3152 invltlb(); 3153 3154 return ((void *)(va + offset)); 3155} 3156 3157void 3158pmap_unmapdev(va, size) 3159 vm_offset_t va; 3160 vm_size_t size; 3161{ 3162 vm_offset_t base, offset; 3163 3164 base = va & PG_FRAME; 3165 offset = va & PAGE_MASK; 3166 size = roundup(offset + size, PAGE_SIZE); 3167 kmem_free(kernel_map, base, size); 3168} 3169 3170/* 3171 * perform the pmap work for mincore 3172 */ 3173int 3174pmap_mincore(pmap, addr) 3175 pmap_t pmap; 3176 vm_offset_t addr; 3177{ 3178 3179 unsigned *ptep, pte; 3180 vm_page_t m; 3181 int val = 0; 3182 3183 ptep = pmap_pte(pmap, addr); 3184 if (ptep == 0) { 3185 return 0; 3186 } 3187 3188 if ((pte = *ptep) != 0) { 3189 vm_offset_t pa; 3190 3191 val = MINCORE_INCORE; 3192 if ((pte & PG_MANAGED) == 0) 3193 return val; 3194 3195 pa = pte & PG_FRAME; 3196 3197 m = PHYS_TO_VM_PAGE(pa); 3198 3199 /* 3200 * Modified by us 3201 */ 3202 if (pte & PG_M) 3203 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3204 /* 3205 * Modified by someone 3206 */ 3207 else if (m->dirty || pmap_is_modified(m)) 3208 val |= MINCORE_MODIFIED_OTHER; 3209 /* 3210 * Referenced by us 3211 */ 3212 if (pte & PG_A) 3213 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3214 3215 /* 3216 * Referenced by someone 3217 */ 3218 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3219 val |= MINCORE_REFERENCED_OTHER; 3220 vm_page_flag_set(m, PG_REFERENCED); 3221 } 3222 } 3223 return val; 3224} 3225 3226void 3227pmap_activate(struct proc *p) 3228{ 3229 pmap_t pmap; 3230 3231 pmap = vmspace_pmap(p->p_vmspace); 3232#if defined(SMP) 3233 pmap->pm_active |= 1 << PCPU_GET(cpuid); 3234#else 3235 pmap->pm_active |= 1; 3236#endif 3237#if defined(SWTCH_OPTIM_STATS) 3238 tlb_flush_count++; 3239#endif 3240 load_cr3(p->p_addr->u_pcb.pcb_cr3 = vtophys(pmap->pm_pdir)); 3241} 3242 3243vm_offset_t 3244pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3245{ 3246 3247 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3248 return addr; 3249 } 3250 3251 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3252 return addr; 3253} 3254 3255 3256#if defined(PMAP_DEBUG) 3257pmap_pid_dump(int pid) 3258{ 3259 pmap_t pmap; 3260 struct proc *p; 3261 int npte = 0; 3262 int index; 3263 ALLPROC_LOCK(AP_SHARED); 3264 LIST_FOREACH(p, &allproc, p_list) { 3265 if (p->p_pid != pid) 3266 continue; 3267 3268 if (p->p_vmspace) { 3269 int i,j; 3270 index = 0; 3271 pmap = vmspace_pmap(p->p_vmspace); 3272 for(i=0;i<1024;i++) { 3273 pd_entry_t *pde; 3274 unsigned *pte; 3275 unsigned base = i << PDRSHIFT; 3276 3277 pde = &pmap->pm_pdir[i]; 3278 if (pde && pmap_pde_v(pde)) { 3279 for(j=0;j<1024;j++) { 3280 unsigned va = base + (j << PAGE_SHIFT); 3281 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3282 if (index) { 3283 index = 0; 3284 printf("\n"); 3285 } 3286 ALLPROC_LOCK(AP_RELEASE); 3287 return npte; 3288 } 3289 pte = pmap_pte_quick( pmap, va); 3290 if (pte && pmap_pte_v(pte)) { 3291 vm_offset_t pa; 3292 vm_page_t m; 3293 pa = *(int *)pte; 3294 m = PHYS_TO_VM_PAGE(pa); 3295 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3296 va, pa, m->hold_count, m->wire_count, m->flags); 3297 npte++; 3298 index++; 3299 if (index >= 2) { 3300 index = 0; 3301 printf("\n"); 3302 } else { 3303 printf(" "); 3304 } 3305 } 3306 } 3307 } 3308 } 3309 } 3310 } 3311 ALLPROC_LOCK(AP_RELEASE); 3312 return npte; 3313} 3314#endif 3315 3316#if defined(DEBUG) 3317 3318static void pads __P((pmap_t pm)); 3319void pmap_pvdump __P((vm_offset_t pa)); 3320 3321/* print address space of pmap*/ 3322static void 3323pads(pm) 3324 pmap_t pm; 3325{ 3326 unsigned va, i, j; 3327 unsigned *ptep; 3328 3329 if (pm == kernel_pmap) 3330 return; 3331 for (i = 0; i < 1024; i++) 3332 if (pm->pm_pdir[i]) 3333 for (j = 0; j < 1024; j++) { 3334 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3335 if (pm == kernel_pmap && va < KERNBASE) 3336 continue; 3337 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3338 continue; 3339 ptep = pmap_pte_quick(pm, va); 3340 if (pmap_pte_v(ptep)) 3341 printf("%x:%x ", va, *(int *) ptep); 3342 }; 3343 3344} 3345 3346void 3347pmap_pvdump(pa) 3348 vm_offset_t pa; 3349{ 3350 register pv_entry_t pv; 3351 vm_page_t m; 3352 3353 printf("pa %x", pa); 3354 m = PHYS_TO_VM_PAGE(pa); 3355 for (pv = TAILQ_FIRST(&m->md.pv_list); 3356 pv; 3357 pv = TAILQ_NEXT(pv, pv_list)) { 3358#ifdef used_to_be 3359 printf(" -> pmap %p, va %x, flags %x", 3360 (void *)pv->pv_pmap, pv->pv_va, pv->pv_flags); 3361#endif 3362 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3363 pads(pv->pv_pmap); 3364 } 3365 printf(" "); 3366} 3367#endif 3368