pmap.c revision 95710
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 95710 2002-04-29 07:43:16Z peter $ 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_kstack_pages.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/uma.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#endif /* SMP || APIC_IO */ 109 110#define PMAP_KEEP_PDIRS 111#ifndef PMAP_SHPGPERPROC 112#define PMAP_SHPGPERPROC 200 113#endif 114 115#if defined(DIAGNOSTIC) 116#define PMAP_DIAGNOSTIC 117#endif 118 119#define MINPV 2048 120 121#if !defined(PMAP_DIAGNOSTIC) 122#define PMAP_INLINE __inline 123#else 124#define PMAP_INLINE 125#endif 126 127/* 128 * Get PDEs and PTEs for user/kernel address space 129 */ 130#define pmap_pde(m, v) (&((m)->pm_pdir[(vm_offset_t)(v) >> PDRSHIFT])) 131#define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT]) 132 133#define pmap_pde_v(pte) ((*(int *)pte & PG_V) != 0) 134#define pmap_pte_w(pte) ((*(int *)pte & PG_W) != 0) 135#define pmap_pte_m(pte) ((*(int *)pte & PG_M) != 0) 136#define pmap_pte_u(pte) ((*(int *)pte & PG_A) != 0) 137#define pmap_pte_v(pte) ((*(int *)pte & PG_V) != 0) 138 139#define pmap_pte_set_w(pte, v) ((v)?(*(int *)pte |= PG_W):(*(int *)pte &= ~PG_W)) 140#define pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v))) 141 142/* 143 * Given a map and a machine independent protection code, 144 * convert to a vax protection code. 145 */ 146#define pte_prot(m, p) (protection_codes[p]) 147static int protection_codes[8]; 148 149struct pmap kernel_pmap_store; 150LIST_HEAD(pmaplist, pmap); 151struct pmaplist allpmaps; 152 153vm_offset_t avail_start; /* PA of first available physical page */ 154vm_offset_t avail_end; /* PA of last available physical page */ 155vm_offset_t virtual_avail; /* VA of first avail page (after kernel bss) */ 156vm_offset_t virtual_end; /* VA of last avail page (end of kernel AS) */ 157static boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */ 158static int pgeflag; /* PG_G or-in */ 159static int pseflag; /* PG_PS or-in */ 160 161static vm_object_t kptobj; 162 163static int nkpt; 164vm_offset_t kernel_vm_end; 165 166/* 167 * Data for the pv entry allocation mechanism 168 */ 169static uma_zone_t pvzone; 170static struct vm_object pvzone_obj; 171static int pv_entry_count = 0, pv_entry_max = 0, pv_entry_high_water = 0; 172static int pmap_pagedaemon_waken = 0; 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 pt_entry_t *PADDR1 = 0; 195 196static PMAP_INLINE void free_pv_entry(pv_entry_t pv); 197static pt_entry_t *get_ptbase(pmap_t pmap); 198static pv_entry_t get_pv_entry(void); 199static void i386_protection_init(void); 200static __inline void pmap_changebit(vm_page_t m, int bit, boolean_t setem); 201 202static void pmap_remove_all(vm_page_t m); 203static vm_page_t pmap_enter_quick(pmap_t pmap, vm_offset_t va, 204 vm_page_t m, vm_page_t mpte); 205static int pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t sva); 206static void pmap_remove_page(struct pmap *pmap, vm_offset_t va); 207static int pmap_remove_entry(struct pmap *pmap, vm_page_t m, 208 vm_offset_t va); 209static boolean_t pmap_testbit(vm_page_t m, int bit); 210static void pmap_insert_entry(pmap_t pmap, vm_offset_t va, 211 vm_page_t mpte, vm_page_t m); 212 213static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va); 214 215static int pmap_release_free_page(pmap_t pmap, vm_page_t p); 216static vm_page_t _pmap_allocpte(pmap_t pmap, unsigned ptepindex); 217static pt_entry_t *pmap_pte_quick(pmap_t pmap, vm_offset_t va); 218static vm_page_t pmap_page_lookup(vm_object_t object, vm_pindex_t pindex); 219static int pmap_unuse_pt(pmap_t, vm_offset_t, vm_page_t); 220static vm_offset_t pmap_kmem_choose(vm_offset_t addr); 221static void *pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait); 222 223static pd_entry_t 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 pt_entry_t * 233pmap_pte(pmap, va) 234 register pmap_t pmap; 235 vm_offset_t va; 236{ 237 pd_entry_t *pdeaddr; 238 239 if (pmap) { 240 pdeaddr = 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 int i; 286 287 avail_start = firstaddr; 288 289 /* 290 * XXX The calculation of virtual_avail is wrong. It's NKPT*PAGE_SIZE too 291 * large. It should instead be correctly calculated in locore.s and 292 * not based on 'first' (which is a physical address, not a virtual 293 * address, for the start of unused physical memory). The kernel 294 * page tables are NOT double mapped and thus should not be included 295 * in this calculation. 296 */ 297 virtual_avail = (vm_offset_t) KERNBASE + firstaddr; 298 virtual_avail = pmap_kmem_choose(virtual_avail); 299 300 virtual_end = VM_MAX_KERNEL_ADDRESS; 301 302 /* 303 * Initialize protection array. 304 */ 305 i386_protection_init(); 306 307 /* 308 * Initialize the kernel pmap (which is statically allocated). 309 */ 310 kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD); 311 kernel_pmap->pm_active = -1; /* don't allow deactivation */ 312 TAILQ_INIT(&kernel_pmap->pm_pvlist); 313 LIST_INIT(&allpmaps); 314 LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list); 315 nkpt = NKPT; 316 317 /* 318 * Reserve some special page table entries/VA space for temporary 319 * mapping of pages. 320 */ 321#define SYSMAP(c, p, v, n) \ 322 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n); 323 324 va = virtual_avail; 325 pte = (pt_entry_t *) pmap_pte(kernel_pmap, va); 326 327 /* 328 * CMAP1/CMAP2 are used for zeroing and copying pages. 329 */ 330 SYSMAP(caddr_t, CMAP1, CADDR1, 1) 331 SYSMAP(caddr_t, CMAP2, CADDR2, 1) 332 333 /* 334 * Crashdump maps. 335 */ 336 SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS); 337 338 /* 339 * ptvmmap is used for reading arbitrary physical pages via /dev/mem. 340 * XXX ptmmap is not used. 341 */ 342 SYSMAP(caddr_t, ptmmap, ptvmmap, 1) 343 344 /* 345 * msgbufp is used to map the system message buffer. 346 * XXX msgbufmap is not used. 347 */ 348 SYSMAP(struct msgbuf *, msgbufmap, msgbufp, 349 atop(round_page(MSGBUF_SIZE))) 350 351 /* 352 * ptemap is used for pmap_pte_quick 353 */ 354 SYSMAP(pt_entry_t *, PMAP1, PADDR1, 1); 355 356 virtual_avail = va; 357 358 *CMAP1 = *CMAP2 = 0; 359 for (i = 0; i < NKPT; i++) 360 PTD[i] = 0; 361 362 pgeflag = 0; 363#if !defined(SMP) /* XXX - see also mp_machdep.c */ 364 if (cpu_feature & CPUID_PGE) { 365 pgeflag = PG_G; 366 } 367#endif 368 369/* 370 * Initialize the 4MB page size flag 371 */ 372 pseflag = 0; 373/* 374 * The 4MB page version of the initial 375 * kernel page mapping. 376 */ 377 pdir4mb = 0; 378 379#if !defined(DISABLE_PSE) 380 if (cpu_feature & CPUID_PSE) { 381 pd_entry_t ptditmp; 382 /* 383 * Note that we have enabled PSE mode 384 */ 385 pseflag = PG_PS; 386 ptditmp = *(PTmap + i386_btop(KERNBASE)); 387 ptditmp &= ~(NBPDR - 1); 388 ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag; 389 pdir4mb = ptditmp; 390 391#if !defined(SMP) 392 /* 393 * Enable the PSE mode. 394 */ 395 load_cr4(rcr4() | CR4_PSE); 396 397 /* 398 * We can do the mapping here for the single processor 399 * case. We simply ignore the old page table page from 400 * now on. 401 */ 402 /* 403 * For SMP, we still need 4K pages to bootstrap APs, 404 * PSE will be enabled as soon as all APs are up. 405 */ 406 PTD[KPTDI] = (pd_entry_t) ptditmp; 407 kernel_pmap->pm_pdir[KPTDI] = (pd_entry_t) ptditmp; 408 invltlb(); 409#endif 410 } 411#endif 412 413#ifdef SMP 414 if (cpu_apic_address == 0) 415 panic("pmap_bootstrap: no local apic! (non-SMP hardware?)"); 416 417 /* local apic is mapped on last page */ 418 SMPpt[NPTEPG - 1] = (pt_entry_t)(PG_V | PG_RW | PG_N | pgeflag | 419 (cpu_apic_address & PG_FRAME)); 420#endif 421 422 invltlb(); 423} 424 425#ifdef SMP 426/* 427 * Set 4mb pdir for mp startup 428 */ 429void 430pmap_set_opt(void) 431{ 432 if (pseflag && (cpu_feature & CPUID_PSE)) { 433 load_cr4(rcr4() | CR4_PSE); 434 if (pdir4mb && PCPU_GET(cpuid) == 0) { /* only on BSP */ 435 kernel_pmap->pm_pdir[KPTDI] = PTD[KPTDI] = pdir4mb; 436 cpu_invltlb(); 437 } 438 } 439} 440#endif 441 442void * 443pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait) 444{ 445 *flags = UMA_SLAB_PRIV; 446 return (void *)kmem_alloc(kernel_map, bytes); 447} 448 449/* 450 * Initialize the pmap module. 451 * Called by vm_init, to initialize any structures that the pmap 452 * system needs to map virtual memory. 453 * pmap_init has been enhanced to support in a fairly consistant 454 * way, discontiguous physical memory. 455 */ 456void 457pmap_init(phys_start, phys_end) 458 vm_offset_t phys_start, phys_end; 459{ 460 int i; 461 int initial_pvs; 462 463 /* 464 * object for kernel page table pages 465 */ 466 kptobj = vm_object_allocate(OBJT_DEFAULT, NKPDE); 467 468 /* 469 * Allocate memory for random pmap data structures. Includes the 470 * pv_head_table. 471 */ 472 473 for(i = 0; i < vm_page_array_size; i++) { 474 vm_page_t m; 475 476 m = &vm_page_array[i]; 477 TAILQ_INIT(&m->md.pv_list); 478 m->md.pv_list_count = 0; 479 } 480 481 /* 482 * init the pv free list 483 */ 484 initial_pvs = vm_page_array_size; 485 if (initial_pvs < MINPV) 486 initial_pvs = MINPV; 487 pvzone = uma_zcreate("PV ENTRY", sizeof (struct pv_entry), NULL, NULL, 488 NULL, NULL, UMA_ALIGN_PTR, 0); 489 uma_zone_set_allocf(pvzone, pmap_allocf); 490 uma_prealloc(pvzone, initial_pvs); 491 492 /* 493 * Now it is safe to enable pv_table recording. 494 */ 495 pmap_initialized = TRUE; 496} 497 498/* 499 * Initialize the address space (zone) for the pv_entries. Set a 500 * high water mark so that the system can recover from excessive 501 * numbers of pv entries. 502 */ 503void 504pmap_init2() 505{ 506 int shpgperproc = PMAP_SHPGPERPROC; 507 508 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc); 509 pv_entry_max = shpgperproc * maxproc + vm_page_array_size; 510 TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max); 511 pv_entry_high_water = 9 * (pv_entry_max / 10); 512 uma_zone_set_obj(pvzone, &pvzone_obj, pv_entry_max); 513} 514 515 516/*************************************************** 517 * Low level helper routines..... 518 ***************************************************/ 519 520#if defined(PMAP_DIAGNOSTIC) 521 522/* 523 * This code checks for non-writeable/modified pages. 524 * This should be an invalid condition. 525 */ 526static int 527pmap_nw_modified(pt_entry_t ptea) 528{ 529 int pte; 530 531 pte = (int) ptea; 532 533 if ((pte & (PG_M|PG_RW)) == PG_M) 534 return 1; 535 else 536 return 0; 537} 538#endif 539 540 541/* 542 * this routine defines the region(s) of memory that should 543 * not be tested for the modified bit. 544 */ 545static PMAP_INLINE int 546pmap_track_modified(vm_offset_t va) 547{ 548 if ((va < kmi.clean_sva) || (va >= kmi.clean_eva)) 549 return 1; 550 else 551 return 0; 552} 553 554static PMAP_INLINE void 555invltlb_1pg(vm_offset_t va) 556{ 557#ifdef I386_CPU 558 invltlb(); 559#else 560 invlpg(va); 561#endif 562} 563 564static __inline void 565pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 566{ 567#if defined(SMP) 568 if (pmap->pm_active & PCPU_GET(cpumask)) 569 cpu_invlpg((void *)va); 570 if (pmap->pm_active & PCPU_GET(other_cpus)) 571 smp_invltlb(); 572#else 573 if (pmap->pm_active) 574 invltlb_1pg(va); 575#endif 576} 577 578static __inline void 579pmap_invalidate_all(pmap_t pmap) 580{ 581#if defined(SMP) 582 if (pmap->pm_active & PCPU_GET(cpumask)) 583 cpu_invltlb(); 584 if (pmap->pm_active & PCPU_GET(other_cpus)) 585 smp_invltlb(); 586#else 587 if (pmap->pm_active) 588 invltlb(); 589#endif 590} 591 592/* 593 * Return an address which is the base of the Virtual mapping of 594 * all the PTEs for the given pmap. Note this doesn't say that 595 * all the PTEs will be present or that the pages there are valid. 596 * The PTEs are made available by the recursive mapping trick. 597 * It will map in the alternate PTE space if needed. 598 */ 599static pt_entry_t * 600get_ptbase(pmap) 601 pmap_t pmap; 602{ 603 pd_entry_t frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 604 605 /* are we current address space or kernel? */ 606 if (pmap == kernel_pmap || frame == (PTDpde & PG_FRAME)) 607 return PTmap; 608 /* otherwise, we are alternate address space */ 609 if (frame != (APTDpde & PG_FRAME)) { 610 APTDpde = (pd_entry_t) (frame | PG_RW | PG_V); 611#if defined(SMP) 612 /* The page directory is not shared between CPUs */ 613 cpu_invltlb(); 614#else 615 invltlb(); 616#endif 617 } 618 return APTmap; 619} 620 621/* 622 * Super fast pmap_pte routine best used when scanning 623 * the pv lists. This eliminates many coarse-grained 624 * invltlb calls. Note that many of the pv list 625 * scans are across different pmaps. It is very wasteful 626 * to do an entire invltlb for checking a single mapping. 627 */ 628 629static pt_entry_t * 630pmap_pte_quick(pmap, va) 631 register pmap_t pmap; 632 vm_offset_t va; 633{ 634 pd_entry_t pde, newpf; 635 pde = pmap->pm_pdir[va >> PDRSHIFT]; 636 if (pde != 0) { 637 pd_entry_t frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 638 unsigned index = i386_btop(va); 639 /* are we current address space or kernel? */ 640 if (pmap == kernel_pmap || frame == (PTDpde & PG_FRAME)) 641 return PTmap + index; 642 newpf = pde & PG_FRAME; 643 if (((*PMAP1) & PG_FRAME) != newpf) { 644 *PMAP1 = newpf | PG_RW | PG_V; 645 invltlb_1pg((vm_offset_t) PADDR1); 646 } 647 return PADDR1 + (index & (NPTEPG - 1)); 648 } 649 return (0); 650} 651 652/* 653 * Routine: pmap_extract 654 * Function: 655 * Extract the physical page address associated 656 * with the given map/virtual_address pair. 657 */ 658vm_offset_t 659pmap_extract(pmap, va) 660 register pmap_t pmap; 661 vm_offset_t va; 662{ 663 vm_offset_t rtval; /* XXX FIXME */ 664 vm_offset_t pdirindex; 665 666 if (pmap == 0) 667 return 0; 668 pdirindex = va >> PDRSHIFT; 669 rtval = pmap->pm_pdir[pdirindex]; 670 if (rtval != 0) { 671 pt_entry_t *pte; 672 if ((rtval & PG_PS) != 0) { 673 rtval &= ~(NBPDR - 1); 674 rtval |= va & (NBPDR - 1); 675 return rtval; 676 } 677 pte = get_ptbase(pmap) + i386_btop(va); 678 rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); 679 return rtval; 680 } 681 return 0; 682 683} 684 685/*************************************************** 686 * Low level mapping routines..... 687 ***************************************************/ 688 689/* 690 * add a wired page to the kva 691 * note that in order for the mapping to take effect -- you 692 * should do a invltlb after doing the pmap_kenter... 693 */ 694PMAP_INLINE void 695pmap_kenter(vm_offset_t va, vm_offset_t pa) 696{ 697 pt_entry_t *pte; 698 pt_entry_t npte, opte; 699 700 npte = pa | PG_RW | PG_V | pgeflag; 701 pte = vtopte(va); 702 opte = *pte; 703 *pte = npte; 704 invltlb_1pg(va); 705} 706 707/* 708 * remove a page from the kernel pagetables 709 */ 710PMAP_INLINE void 711pmap_kremove(vm_offset_t va) 712{ 713 register pt_entry_t *pte; 714 715 pte = vtopte(va); 716 *pte = 0; 717 invltlb_1pg(va); 718} 719 720/* 721 * Used to map a range of physical addresses into kernel 722 * virtual address space. 723 * 724 * The value passed in '*virt' is a suggested virtual address for 725 * the mapping. Architectures which can support a direct-mapped 726 * physical to virtual region can return the appropriate address 727 * within that region, leaving '*virt' unchanged. Other 728 * architectures should map the pages starting at '*virt' and 729 * update '*virt' with the first usable address after the mapped 730 * region. 731 */ 732vm_offset_t 733pmap_map(vm_offset_t *virt, vm_offset_t start, vm_offset_t end, int prot) 734{ 735 vm_offset_t sva = *virt; 736 vm_offset_t va = sva; 737 while (start < end) { 738 pmap_kenter(va, start); 739 va += PAGE_SIZE; 740 start += PAGE_SIZE; 741 } 742 *virt = va; 743 return (sva); 744} 745 746 747/* 748 * Add a list of wired pages to the kva 749 * this routine is only used for temporary 750 * kernel mappings that do not need to have 751 * page modification or references recorded. 752 * Note that old mappings are simply written 753 * over. The page *must* be wired. 754 */ 755void 756pmap_qenter(vm_offset_t va, vm_page_t *m, int count) 757{ 758 vm_offset_t end_va; 759 760 end_va = va + count * PAGE_SIZE; 761 762 while (va < end_va) { 763 pt_entry_t *pte; 764 765 pte = vtopte(va); 766 *pte = VM_PAGE_TO_PHYS(*m) | PG_RW | PG_V | pgeflag; 767#ifdef SMP 768 cpu_invlpg((void *)va); 769#else 770 invltlb_1pg(va); 771#endif 772 va += PAGE_SIZE; 773 m++; 774 } 775#ifdef SMP 776 smp_invltlb(); 777#endif 778} 779 780/* 781 * this routine jerks page mappings from the 782 * kernel -- it is meant only for temporary mappings. 783 */ 784void 785pmap_qremove(vm_offset_t va, int count) 786{ 787 vm_offset_t end_va; 788 789 end_va = va + count*PAGE_SIZE; 790 791 while (va < end_va) { 792 pt_entry_t *pte; 793 794 pte = 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(vm_object_t object, vm_pindex_t pindex) 810{ 811 vm_page_t m; 812retry: 813 m = vm_page_lookup(object, pindex); 814 if (m && vm_page_sleep_busy(m, FALSE, "pplookp")) 815 goto retry; 816 return m; 817} 818 819/* 820 * Create the Uarea stack for a new process. 821 * This routine directly affects the fork perf for a process. 822 */ 823void 824pmap_new_proc(struct proc *p) 825{ 826#ifdef I386_CPU 827 int updateneeded = 0; 828#endif 829 int i; 830 vm_object_t upobj; 831 vm_offset_t up; 832 vm_page_t m; 833 pt_entry_t *ptek, oldpte; 834 835 /* 836 * allocate object for the upages 837 */ 838 upobj = p->p_upages_obj; 839 if (upobj == NULL) { 840 upobj = vm_object_allocate(OBJT_DEFAULT, UAREA_PAGES); 841 p->p_upages_obj = upobj; 842 } 843 844 /* get a kernel virtual address for the U area for this thread */ 845 up = (vm_offset_t)p->p_uarea; 846 if (up == 0) { 847 up = kmem_alloc_nofault(kernel_map, UAREA_PAGES * PAGE_SIZE); 848 if (up == 0) 849 panic("pmap_new_proc: upage allocation failed"); 850 p->p_uarea = (struct user *)up; 851 } 852 853 ptek = vtopte(up); 854 855 for (i = 0; i < UAREA_PAGES; i++) { 856 /* 857 * Get a kernel stack page 858 */ 859 m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 860 861 /* 862 * Wire the page 863 */ 864 m->wire_count++; 865 cnt.v_wire_count++; 866 867 oldpte = *(ptek + i); 868 /* 869 * Enter the page into the kernel address space. 870 */ 871 *(ptek + i) = VM_PAGE_TO_PHYS(m) | PG_RW | PG_V | pgeflag; 872 if (oldpte) { 873#ifdef I386_CPU 874 updateneeded = 1; 875#else 876 invlpg(up + i * PAGE_SIZE); 877#endif 878 } 879 880 vm_page_wakeup(m); 881 vm_page_flag_clear(m, PG_ZERO); 882 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 883 m->valid = VM_PAGE_BITS_ALL; 884 } 885#ifdef I386_CPU 886 if (updateneeded) 887 invltlb(); 888#endif 889} 890 891/* 892 * Dispose the U-Area for a process that has exited. 893 * This routine directly impacts the exit perf of a process. 894 */ 895void 896pmap_dispose_proc(p) 897 struct proc *p; 898{ 899 int i; 900 vm_object_t upobj; 901 vm_offset_t up; 902 vm_page_t m; 903 pt_entry_t *ptek, oldpte; 904 905 upobj = p->p_upages_obj; 906 up = (vm_offset_t)p->p_uarea; 907 ptek = vtopte(up); 908 for (i = 0; i < UAREA_PAGES; i++) { 909 m = vm_page_lookup(upobj, i); 910 if (m == NULL) 911 panic("pmap_dispose_proc: upage already missing?"); 912 vm_page_busy(m); 913 oldpte = *(ptek + i); 914 *(ptek + i) = 0; 915#ifndef I386_CPU 916 invlpg(up + i * PAGE_SIZE); 917#endif 918 vm_page_unwire(m, 0); 919 vm_page_free(m); 920 } 921#ifdef I386_CPU 922 invltlb(); 923#endif 924 925 /* 926 * If the process got swapped out some of its UPAGES might have gotten 927 * swapped. Just get rid of the object to clean up the swap use 928 * proactively. NOTE! might block waiting for paging I/O to complete. 929 */ 930 if (upobj->type == OBJT_SWAP) { 931 p->p_upages_obj = NULL; 932 vm_object_deallocate(upobj); 933 } 934} 935 936/* 937 * Allow the U_AREA for a process to be prejudicially paged out. 938 */ 939void 940pmap_swapout_proc(p) 941 struct proc *p; 942{ 943 int i; 944 vm_object_t upobj; 945 vm_offset_t up; 946 vm_page_t m; 947 948 upobj = p->p_upages_obj; 949 up = (vm_offset_t)p->p_uarea; 950 for (i = 0; i < UAREA_PAGES; i++) { 951 m = vm_page_lookup(upobj, i); 952 if (m == NULL) 953 panic("pmap_swapout_proc: upage already missing?"); 954 vm_page_dirty(m); 955 vm_page_unwire(m, 0); 956 pmap_kremove(up + i * PAGE_SIZE); 957 } 958} 959 960/* 961 * Bring the U-Area for a specified process back in. 962 */ 963void 964pmap_swapin_proc(p) 965 struct proc *p; 966{ 967 int i, rv; 968 vm_object_t upobj; 969 vm_offset_t up; 970 vm_page_t m; 971 972 upobj = p->p_upages_obj; 973 up = (vm_offset_t)p->p_uarea; 974 for (i = 0; i < UAREA_PAGES; i++) { 975 m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 976 pmap_kenter(up + i * PAGE_SIZE, VM_PAGE_TO_PHYS(m)); 977 if (m->valid != VM_PAGE_BITS_ALL) { 978 rv = vm_pager_get_pages(upobj, &m, 1, 0); 979 if (rv != VM_PAGER_OK) 980 panic("pmap_swapin_proc: cannot get upage for proc: %d\n", p->p_pid); 981 m = vm_page_lookup(upobj, i); 982 m->valid = VM_PAGE_BITS_ALL; 983 } 984 vm_page_wire(m); 985 vm_page_wakeup(m); 986 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 987 } 988} 989 990/* 991 * Create the kernel stack (including pcb for i386) for a new thread. 992 * This routine directly affects the fork perf for a process and 993 * create performance for a thread. 994 */ 995void 996pmap_new_thread(struct thread *td) 997{ 998#ifdef I386_CPU 999 int updateneeded = 0; 1000#endif 1001 int i; 1002 vm_object_t ksobj; 1003 vm_page_t m; 1004 vm_offset_t ks; 1005 pt_entry_t *ptek, oldpte; 1006 1007 /* 1008 * allocate object for the kstack 1009 */ 1010 ksobj = td->td_kstack_obj; 1011 if (ksobj == NULL) { 1012 ksobj = vm_object_allocate(OBJT_DEFAULT, KSTACK_PAGES); 1013 td->td_kstack_obj = ksobj; 1014 } 1015 1016#ifdef KSTACK_GUARD 1017 /* get a kernel virtual address for the kstack for this thread */ 1018 ks = td->td_kstack; 1019 if (ks == 0) { 1020 ks = kmem_alloc_nofault(kernel_map, 1021 (KSTACK_PAGES + 1) * PAGE_SIZE); 1022 if (ks == 0) 1023 panic("pmap_new_thread: kstack allocation failed"); 1024 ks += PAGE_SIZE; 1025 td->td_kstack = ks; 1026 } 1027 1028 ptek = vtopte(ks - PAGE_SIZE); 1029 oldpte = *ptek; 1030 *ptek = 0; 1031 if (oldpte) { 1032#ifdef I386_CPU 1033 updateneeded = 1; 1034#else 1035 invlpg(ks - PAGE_SIZE); 1036#endif 1037 } 1038 ptek++; 1039#else 1040 /* get a kernel virtual address for the kstack for this thread */ 1041 ks = td->td_kstack; 1042 if (ks == 0) { 1043 ks = kmem_alloc_nofault(kernel_map, KSTACK_PAGES * PAGE_SIZE); 1044 if (ks == 0) 1045 panic("pmap_new_thread: kstack allocation failed"); 1046 td->td_kstack = ks; 1047 } 1048 ptek = vtopte(ks); 1049#endif 1050 for (i = 0; i < KSTACK_PAGES; i++) { 1051 /* 1052 * Get a kernel stack page 1053 */ 1054 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1055 1056 /* 1057 * Wire the page 1058 */ 1059 m->wire_count++; 1060 cnt.v_wire_count++; 1061 1062 oldpte = *(ptek + i); 1063 /* 1064 * Enter the page into the kernel address space. 1065 */ 1066 *(ptek + i) = VM_PAGE_TO_PHYS(m) | PG_RW | PG_V | pgeflag; 1067 if (oldpte) { 1068#ifdef I386_CPU 1069 updateneeded = 1; 1070#else 1071 invlpg(ks + i * PAGE_SIZE); 1072#endif 1073 } 1074 1075 vm_page_wakeup(m); 1076 vm_page_flag_clear(m, PG_ZERO); 1077 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 1078 m->valid = VM_PAGE_BITS_ALL; 1079 } 1080#ifdef I386_CPU 1081 if (updateneeded) 1082 invltlb(); 1083#endif 1084} 1085 1086/* 1087 * Dispose the kernel stack for a thread that has exited. 1088 * This routine directly impacts the exit perf of a process and thread. 1089 */ 1090void 1091pmap_dispose_thread(td) 1092 struct thread *td; 1093{ 1094 int i; 1095 vm_object_t ksobj; 1096 vm_offset_t ks; 1097 vm_page_t m; 1098 pt_entry_t *ptek, oldpte; 1099 1100 ksobj = td->td_kstack_obj; 1101 ks = td->td_kstack; 1102 ptek = vtopte(ks); 1103 for (i = 0; i < KSTACK_PAGES; i++) { 1104 m = vm_page_lookup(ksobj, i); 1105 if (m == NULL) 1106 panic("pmap_dispose_thread: kstack already missing?"); 1107 vm_page_busy(m); 1108 oldpte = *(ptek + i); 1109 *(ptek + i) = 0; 1110#ifndef I386_CPU 1111 invlpg(ks + i * PAGE_SIZE); 1112#endif 1113 vm_page_unwire(m, 0); 1114 vm_page_free(m); 1115 } 1116#ifdef I386_CPU 1117 invltlb(); 1118#endif 1119 1120 /* 1121 * If the thread got swapped out some of its KSTACK might have gotten 1122 * swapped. Just get rid of the object to clean up the swap use 1123 * proactively. NOTE! might block waiting for paging I/O to complete. 1124 */ 1125 if (ksobj->type == OBJT_SWAP) { 1126 td->td_kstack_obj = NULL; 1127 vm_object_deallocate(ksobj); 1128 } 1129} 1130 1131/* 1132 * Allow the Kernel stack for a thread to be prejudicially paged out. 1133 */ 1134void 1135pmap_swapout_thread(td) 1136 struct thread *td; 1137{ 1138 int i; 1139 vm_object_t ksobj; 1140 vm_offset_t ks; 1141 vm_page_t m; 1142 1143 ksobj = td->td_kstack_obj; 1144 ks = td->td_kstack; 1145 for (i = 0; i < KSTACK_PAGES; i++) { 1146 m = vm_page_lookup(ksobj, i); 1147 if (m == NULL) 1148 panic("pmap_swapout_thread: kstack already missing?"); 1149 vm_page_dirty(m); 1150 vm_page_unwire(m, 0); 1151 pmap_kremove(ks + i * PAGE_SIZE); 1152 } 1153} 1154 1155/* 1156 * Bring the kernel stack for a specified thread back in. 1157 */ 1158void 1159pmap_swapin_thread(td) 1160 struct thread *td; 1161{ 1162 int i, rv; 1163 vm_object_t ksobj; 1164 vm_offset_t ks; 1165 vm_page_t m; 1166 1167 ksobj = td->td_kstack_obj; 1168 ks = td->td_kstack; 1169 for (i = 0; i < KSTACK_PAGES; i++) { 1170 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1171 pmap_kenter(ks + i * PAGE_SIZE, VM_PAGE_TO_PHYS(m)); 1172 if (m->valid != VM_PAGE_BITS_ALL) { 1173 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1174 if (rv != VM_PAGER_OK) 1175 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1176 m = vm_page_lookup(ksobj, i); 1177 m->valid = VM_PAGE_BITS_ALL; 1178 } 1179 vm_page_wire(m); 1180 vm_page_wakeup(m); 1181 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 1182 } 1183} 1184 1185/*************************************************** 1186 * Page table page management routines..... 1187 ***************************************************/ 1188 1189/* 1190 * This routine unholds page table pages, and if the hold count 1191 * drops to zero, then it decrements the wire count. 1192 */ 1193static int 1194_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1195{ 1196 1197 while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) 1198 ; 1199 1200 if (m->hold_count == 0) { 1201 vm_offset_t pteva; 1202 /* 1203 * unmap the page table page 1204 */ 1205 pmap->pm_pdir[m->pindex] = 0; 1206 --pmap->pm_stats.resident_count; 1207 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1208 (PTDpde & PG_FRAME)) { 1209 /* 1210 * Do a invltlb to make the invalidated mapping 1211 * take effect immediately. 1212 */ 1213 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); 1214 pmap_invalidate_page(pmap, pteva); 1215 } 1216 1217 if (pmap->pm_ptphint == m) 1218 pmap->pm_ptphint = NULL; 1219 1220 /* 1221 * If the page is finally unwired, simply free it. 1222 */ 1223 --m->wire_count; 1224 if (m->wire_count == 0) { 1225 1226 vm_page_flash(m); 1227 vm_page_busy(m); 1228 vm_page_free_zero(m); 1229 --cnt.v_wire_count; 1230 } 1231 return 1; 1232 } 1233 return 0; 1234} 1235 1236static PMAP_INLINE int 1237pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1238{ 1239 vm_page_unhold(m); 1240 if (m->hold_count == 0) 1241 return _pmap_unwire_pte_hold(pmap, m); 1242 else 1243 return 0; 1244} 1245 1246/* 1247 * After removing a page table entry, this routine is used to 1248 * conditionally free the page, and manage the hold/wire counts. 1249 */ 1250static int 1251pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1252{ 1253 unsigned ptepindex; 1254 if (va >= VM_MAXUSER_ADDRESS) 1255 return 0; 1256 1257 if (mpte == NULL) { 1258 ptepindex = (va >> PDRSHIFT); 1259 if (pmap->pm_ptphint && 1260 (pmap->pm_ptphint->pindex == ptepindex)) { 1261 mpte = pmap->pm_ptphint; 1262 } else { 1263 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1264 pmap->pm_ptphint = mpte; 1265 } 1266 } 1267 1268 return pmap_unwire_pte_hold(pmap, mpte); 1269} 1270 1271void 1272pmap_pinit0(pmap) 1273 struct pmap *pmap; 1274{ 1275 pmap->pm_pdir = 1276 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1277 pmap_kenter((vm_offset_t) pmap->pm_pdir, (vm_offset_t) IdlePTD); 1278 pmap->pm_ptphint = NULL; 1279 pmap->pm_active = 0; 1280 TAILQ_INIT(&pmap->pm_pvlist); 1281 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1282 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1283} 1284 1285/* 1286 * Initialize a preallocated and zeroed pmap structure, 1287 * such as one in a vmspace structure. 1288 */ 1289void 1290pmap_pinit(pmap) 1291 register struct pmap *pmap; 1292{ 1293 vm_page_t ptdpg; 1294 1295 /* 1296 * No need to allocate page table space yet but we do need a valid 1297 * page directory table. 1298 */ 1299 if (pmap->pm_pdir == NULL) 1300 pmap->pm_pdir = 1301 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1302 1303 /* 1304 * allocate object for the ptes 1305 */ 1306 if (pmap->pm_pteobj == NULL) 1307 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1308 1309 /* 1310 * allocate the page directory page 1311 */ 1312 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1313 VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1314 1315 ptdpg->wire_count = 1; 1316 ++cnt.v_wire_count; 1317 1318 1319 vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/ 1320 ptdpg->valid = VM_PAGE_BITS_ALL; 1321 1322 pmap_kenter((vm_offset_t) pmap->pm_pdir, VM_PAGE_TO_PHYS(ptdpg)); 1323 if ((ptdpg->flags & PG_ZERO) == 0) 1324 bzero(pmap->pm_pdir, PAGE_SIZE); 1325 1326 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1327 /* Wire in kernel global address entries. */ 1328 /* XXX copies current process, does not fill in MPPTDI */ 1329 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1330#ifdef SMP 1331 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1332#endif 1333 1334 /* install self-referential address mapping entry */ 1335 pmap->pm_pdir[PTDPTDI] = 1336 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1337 1338 pmap->pm_active = 0; 1339 pmap->pm_ptphint = NULL; 1340 TAILQ_INIT(&pmap->pm_pvlist); 1341 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1342} 1343 1344/* 1345 * Wire in kernel global address entries. To avoid a race condition 1346 * between pmap initialization and pmap_growkernel, this procedure 1347 * should be called after the vmspace is attached to the process 1348 * but before this pmap is activated. 1349 */ 1350void 1351pmap_pinit2(pmap) 1352 struct pmap *pmap; 1353{ 1354 /* XXX: Remove this stub when no longer called */ 1355} 1356 1357static int 1358pmap_release_free_page(pmap_t pmap, vm_page_t p) 1359{ 1360 pd_entry_t *pde = pmap->pm_pdir; 1361 /* 1362 * This code optimizes the case of freeing non-busy 1363 * page-table pages. Those pages are zero now, and 1364 * might as well be placed directly into the zero queue. 1365 */ 1366 if (vm_page_sleep_busy(p, FALSE, "pmaprl")) 1367 return 0; 1368 1369 vm_page_busy(p); 1370 1371 /* 1372 * Remove the page table page from the processes address space. 1373 */ 1374 pde[p->pindex] = 0; 1375 pmap->pm_stats.resident_count--; 1376 1377 if (p->hold_count) { 1378 panic("pmap_release: freeing held page table page"); 1379 } 1380 /* 1381 * Page directory pages need to have the kernel 1382 * stuff cleared, so they can go into the zero queue also. 1383 */ 1384 if (p->pindex == PTDPTDI) { 1385 bzero(pde + KPTDI, nkpt * PTESIZE); 1386#ifdef SMP 1387 pde[MPPTDI] = 0; 1388#endif 1389 pde[APTDPTDI] = 0; 1390 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1391 } 1392 1393 if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex)) 1394 pmap->pm_ptphint = NULL; 1395 1396 p->wire_count--; 1397 cnt.v_wire_count--; 1398 vm_page_free_zero(p); 1399 return 1; 1400} 1401 1402/* 1403 * this routine is called if the page table page is not 1404 * mapped correctly. 1405 */ 1406static vm_page_t 1407_pmap_allocpte(pmap, ptepindex) 1408 pmap_t pmap; 1409 unsigned ptepindex; 1410{ 1411 vm_offset_t pteva, ptepa; /* XXXPA */ 1412 vm_page_t m; 1413 1414 /* 1415 * Find or fabricate a new pagetable page 1416 */ 1417 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1418 VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1419 1420 KASSERT(m->queue == PQ_NONE, 1421 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1422 1423 if (m->wire_count == 0) 1424 cnt.v_wire_count++; 1425 m->wire_count++; 1426 1427 /* 1428 * Increment the hold count for the page table page 1429 * (denoting a new mapping.) 1430 */ 1431 m->hold_count++; 1432 1433 /* 1434 * Map the pagetable page into the process address space, if 1435 * it isn't already there. 1436 */ 1437 1438 pmap->pm_stats.resident_count++; 1439 1440 ptepa = VM_PAGE_TO_PHYS(m); 1441 pmap->pm_pdir[ptepindex] = 1442 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1443 1444 /* 1445 * Set the page table hint 1446 */ 1447 pmap->pm_ptphint = m; 1448 1449 /* 1450 * Try to use the new mapping, but if we cannot, then 1451 * do it with the routine that maps the page explicitly. 1452 */ 1453 if ((m->flags & PG_ZERO) == 0) { 1454 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1455 (PTDpde & PG_FRAME)) { 1456 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1457 bzero((caddr_t) pteva, PAGE_SIZE); 1458 } else { 1459 pmap_zero_page(m); 1460 } 1461 } 1462 1463 m->valid = VM_PAGE_BITS_ALL; 1464 vm_page_flag_clear(m, PG_ZERO); 1465 vm_page_flag_set(m, PG_MAPPED); 1466 vm_page_wakeup(m); 1467 1468 return m; 1469} 1470 1471static vm_page_t 1472pmap_allocpte(pmap_t pmap, vm_offset_t va) 1473{ 1474 unsigned ptepindex; 1475 pd_entry_t ptepa; 1476 vm_page_t m; 1477 1478 /* 1479 * Calculate pagetable page index 1480 */ 1481 ptepindex = va >> PDRSHIFT; 1482 1483 /* 1484 * Get the page directory entry 1485 */ 1486 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1487 1488 /* 1489 * This supports switching from a 4MB page to a 1490 * normal 4K page. 1491 */ 1492 if (ptepa & PG_PS) { 1493 pmap->pm_pdir[ptepindex] = 0; 1494 ptepa = 0; 1495 invltlb(); 1496 } 1497 1498 /* 1499 * If the page table page is mapped, we just increment the 1500 * hold count, and activate it. 1501 */ 1502 if (ptepa) { 1503 /* 1504 * In order to get the page table page, try the 1505 * hint first. 1506 */ 1507 if (pmap->pm_ptphint && 1508 (pmap->pm_ptphint->pindex == ptepindex)) { 1509 m = pmap->pm_ptphint; 1510 } else { 1511 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1512 pmap->pm_ptphint = m; 1513 } 1514 m->hold_count++; 1515 return m; 1516 } 1517 /* 1518 * Here if the pte page isn't mapped, or if it has been deallocated. 1519 */ 1520 return _pmap_allocpte(pmap, ptepindex); 1521} 1522 1523 1524/*************************************************** 1525* Pmap allocation/deallocation routines. 1526 ***************************************************/ 1527 1528/* 1529 * Release any resources held by the given physical map. 1530 * Called when a pmap initialized by pmap_pinit is being released. 1531 * Should only be called if the map contains no valid mappings. 1532 */ 1533void 1534pmap_release(pmap_t pmap) 1535{ 1536 vm_page_t p,n,ptdpg; 1537 vm_object_t object = pmap->pm_pteobj; 1538 int curgeneration; 1539 1540#if defined(DIAGNOSTIC) 1541 if (object->ref_count != 1) 1542 panic("pmap_release: pteobj reference count != 1"); 1543#endif 1544 1545 ptdpg = NULL; 1546 LIST_REMOVE(pmap, pm_list); 1547retry: 1548 curgeneration = object->generation; 1549 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1550 n = TAILQ_NEXT(p, listq); 1551 if (p->pindex == PTDPTDI) { 1552 ptdpg = p; 1553 continue; 1554 } 1555 while (1) { 1556 if (!pmap_release_free_page(pmap, p) && 1557 (object->generation != curgeneration)) 1558 goto retry; 1559 } 1560 } 1561 1562 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1563 goto retry; 1564} 1565 1566static int 1567kvm_size(SYSCTL_HANDLER_ARGS) 1568{ 1569 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1570 1571 return sysctl_handle_long(oidp, &ksize, 0, req); 1572} 1573SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1574 0, 0, kvm_size, "IU", "Size of KVM"); 1575 1576static int 1577kvm_free(SYSCTL_HANDLER_ARGS) 1578{ 1579 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1580 1581 return sysctl_handle_long(oidp, &kfree, 0, req); 1582} 1583SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1584 0, 0, kvm_free, "IU", "Amount of KVM free"); 1585 1586/* 1587 * grow the number of kernel page table entries, if needed 1588 */ 1589void 1590pmap_growkernel(vm_offset_t addr) 1591{ 1592 struct pmap *pmap; 1593 int s; 1594 vm_offset_t ptppaddr; 1595 vm_page_t nkpg; 1596 pd_entry_t newpdir; 1597 1598 s = splhigh(); 1599 if (kernel_vm_end == 0) { 1600 kernel_vm_end = KERNBASE; 1601 nkpt = 0; 1602 while (pdir_pde(PTD, kernel_vm_end)) { 1603 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1604 nkpt++; 1605 } 1606 } 1607 addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1608 while (kernel_vm_end < addr) { 1609 if (pdir_pde(PTD, kernel_vm_end)) { 1610 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1611 continue; 1612 } 1613 1614 /* 1615 * This index is bogus, but out of the way 1616 */ 1617 nkpg = vm_page_alloc(kptobj, nkpt, VM_ALLOC_SYSTEM); 1618 if (!nkpg) 1619 panic("pmap_growkernel: no memory to grow kernel"); 1620 1621 nkpt++; 1622 1623 vm_page_wire(nkpg); 1624 pmap_zero_page(nkpg); 1625 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1626 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1627 pdir_pde(PTD, kernel_vm_end) = newpdir; 1628 1629 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1630 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1631 } 1632 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1633 } 1634 splx(s); 1635} 1636 1637 1638/*************************************************** 1639 * page management routines. 1640 ***************************************************/ 1641 1642/* 1643 * free the pv_entry back to the free list 1644 */ 1645static PMAP_INLINE void 1646free_pv_entry(pv_entry_t pv) 1647{ 1648 pv_entry_count--; 1649 uma_zfree(pvzone, pv); 1650} 1651 1652/* 1653 * get a new pv_entry, allocating a block from the system 1654 * when needed. 1655 * the memory allocation is performed bypassing the malloc code 1656 * because of the possibility of allocations at interrupt time. 1657 */ 1658static pv_entry_t 1659get_pv_entry(void) 1660{ 1661 pv_entry_count++; 1662 if (pv_entry_high_water && 1663 (pv_entry_count > pv_entry_high_water) && 1664 (pmap_pagedaemon_waken == 0)) { 1665 pmap_pagedaemon_waken = 1; 1666 wakeup (&vm_pages_needed); 1667 } 1668 return uma_zalloc(pvzone, M_NOWAIT); 1669} 1670 1671/* 1672 * This routine is very drastic, but can save the system 1673 * in a pinch. 1674 */ 1675void 1676pmap_collect() 1677{ 1678 int i; 1679 vm_page_t m; 1680 static int warningdone = 0; 1681 1682 if (pmap_pagedaemon_waken == 0) 1683 return; 1684 1685 if (warningdone < 5) { 1686 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1687 warningdone++; 1688 } 1689 1690 for(i = 0; i < vm_page_array_size; i++) { 1691 m = &vm_page_array[i]; 1692 if (m->wire_count || m->hold_count || m->busy || 1693 (m->flags & (PG_BUSY | PG_UNMANAGED))) 1694 continue; 1695 pmap_remove_all(m); 1696 } 1697 pmap_pagedaemon_waken = 0; 1698} 1699 1700 1701/* 1702 * If it is the first entry on the list, it is actually 1703 * in the header and we must copy the following entry up 1704 * to the header. Otherwise we must search the list for 1705 * the entry. In either case we free the now unused entry. 1706 */ 1707 1708static int 1709pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1710{ 1711 pv_entry_t pv; 1712 int rtval; 1713 int s; 1714 1715 s = splvm(); 1716 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1717 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1718 if (pmap == pv->pv_pmap && va == pv->pv_va) 1719 break; 1720 } 1721 } else { 1722 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1723 if (va == pv->pv_va) 1724 break; 1725 } 1726 } 1727 1728 rtval = 0; 1729 if (pv) { 1730 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1731 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1732 m->md.pv_list_count--; 1733 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1734 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1735 1736 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1737 free_pv_entry(pv); 1738 } 1739 1740 splx(s); 1741 return rtval; 1742} 1743 1744/* 1745 * Create a pv entry for page at pa for 1746 * (pmap, va). 1747 */ 1748static void 1749pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1750{ 1751 1752 int s; 1753 pv_entry_t pv; 1754 1755 s = splvm(); 1756 pv = get_pv_entry(); 1757 pv->pv_va = va; 1758 pv->pv_pmap = pmap; 1759 pv->pv_ptem = mpte; 1760 1761 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1762 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1763 m->md.pv_list_count++; 1764 1765 splx(s); 1766} 1767 1768/* 1769 * pmap_remove_pte: do the things to unmap a page in a process 1770 */ 1771static int 1772pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1773{ 1774 pt_entry_t oldpte; 1775 vm_page_t m; 1776 1777 oldpte = atomic_readandclear_int(ptq); 1778 if (oldpte & PG_W) 1779 pmap->pm_stats.wired_count -= 1; 1780 /* 1781 * Machines that don't support invlpg, also don't support 1782 * PG_G. 1783 */ 1784 if (oldpte & PG_G) 1785 invlpg(va); 1786 pmap->pm_stats.resident_count -= 1; 1787 if (oldpte & PG_MANAGED) { 1788 m = PHYS_TO_VM_PAGE(oldpte); 1789 if (oldpte & PG_M) { 1790#if defined(PMAP_DIAGNOSTIC) 1791 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1792 printf( 1793 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1794 va, oldpte); 1795 } 1796#endif 1797 if (pmap_track_modified(va)) 1798 vm_page_dirty(m); 1799 } 1800 if (oldpte & PG_A) 1801 vm_page_flag_set(m, PG_REFERENCED); 1802 return pmap_remove_entry(pmap, m, va); 1803 } else { 1804 return pmap_unuse_pt(pmap, va, NULL); 1805 } 1806 1807 return 0; 1808} 1809 1810/* 1811 * Remove a single page from a process address space 1812 */ 1813static void 1814pmap_remove_page(pmap_t pmap, vm_offset_t va) 1815{ 1816 register pt_entry_t *ptq; 1817 1818 /* 1819 * if there is no pte for this address, just skip it!!! 1820 */ 1821 if (*pmap_pde(pmap, va) == 0) { 1822 return; 1823 } 1824 1825 /* 1826 * get a local va for mappings for this pmap. 1827 */ 1828 ptq = get_ptbase(pmap) + i386_btop(va); 1829 if (*ptq) { 1830 (void) pmap_remove_pte(pmap, ptq, va); 1831 pmap_invalidate_page(pmap, va); 1832 } 1833 return; 1834} 1835 1836/* 1837 * Remove the given range of addresses from the specified map. 1838 * 1839 * It is assumed that the start and end are properly 1840 * rounded to the page size. 1841 */ 1842void 1843pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1844{ 1845 register pt_entry_t *ptbase; 1846 vm_offset_t pdnxt; 1847 pd_entry_t ptpaddr; 1848 vm_offset_t sindex, eindex; 1849 int anyvalid; 1850 1851 if (pmap == NULL) 1852 return; 1853 1854 if (pmap->pm_stats.resident_count == 0) 1855 return; 1856 1857 /* 1858 * special handling of removing one page. a very 1859 * common operation and easy to short circuit some 1860 * code. 1861 */ 1862 if ((sva + PAGE_SIZE == eva) && 1863 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1864 pmap_remove_page(pmap, sva); 1865 return; 1866 } 1867 1868 anyvalid = 0; 1869 1870 /* 1871 * Get a local virtual address for the mappings that are being 1872 * worked with. 1873 */ 1874 ptbase = get_ptbase(pmap); 1875 1876 sindex = i386_btop(sva); 1877 eindex = i386_btop(eva); 1878 1879 for (; sindex < eindex; sindex = pdnxt) { 1880 unsigned pdirindex; 1881 1882 /* 1883 * Calculate index for next page table. 1884 */ 1885 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1886 if (pmap->pm_stats.resident_count == 0) 1887 break; 1888 1889 pdirindex = sindex / NPDEPG; 1890 ptpaddr = pmap->pm_pdir[pdirindex]; 1891 if ((ptpaddr & PG_PS) != 0) { 1892 pmap->pm_pdir[pdirindex] = 0; 1893 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1894 anyvalid++; 1895 continue; 1896 } 1897 1898 /* 1899 * Weed out invalid mappings. Note: we assume that the page 1900 * directory table is always allocated, and in kernel virtual. 1901 */ 1902 if (ptpaddr == 0) 1903 continue; 1904 1905 /* 1906 * Limit our scan to either the end of the va represented 1907 * by the current page table page, or to the end of the 1908 * range being removed. 1909 */ 1910 if (pdnxt > eindex) { 1911 pdnxt = eindex; 1912 } 1913 1914 for (; sindex != pdnxt; sindex++) { 1915 vm_offset_t va; 1916 if (ptbase[sindex] == 0) { 1917 continue; 1918 } 1919 va = i386_ptob(sindex); 1920 1921 anyvalid++; 1922 if (pmap_remove_pte(pmap, 1923 ptbase + sindex, va)) 1924 break; 1925 } 1926 } 1927 1928 if (anyvalid) 1929 pmap_invalidate_all(pmap); 1930} 1931 1932/* 1933 * Routine: pmap_remove_all 1934 * Function: 1935 * Removes this physical page from 1936 * all physical maps in which it resides. 1937 * Reflects back modify bits to the pager. 1938 * 1939 * Notes: 1940 * Original versions of this routine were very 1941 * inefficient because they iteratively called 1942 * pmap_remove (slow...) 1943 */ 1944 1945static void 1946pmap_remove_all(vm_page_t m) 1947{ 1948 register pv_entry_t pv; 1949 pt_entry_t *pte, tpte; 1950 int s; 1951 1952#if defined(PMAP_DIAGNOSTIC) 1953 /* 1954 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1955 * pages! 1956 */ 1957 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1958 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1959 } 1960#endif 1961 1962 s = splvm(); 1963 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1964 pv->pv_pmap->pm_stats.resident_count--; 1965 1966 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1967 1968 tpte = atomic_readandclear_int(pte); 1969 if (tpte & PG_W) 1970 pv->pv_pmap->pm_stats.wired_count--; 1971 1972 if (tpte & PG_A) 1973 vm_page_flag_set(m, PG_REFERENCED); 1974 1975 /* 1976 * Update the vm_page_t clean and reference bits. 1977 */ 1978 if (tpte & PG_M) { 1979#if defined(PMAP_DIAGNOSTIC) 1980 if (pmap_nw_modified((pt_entry_t) tpte)) { 1981 printf( 1982 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1983 pv->pv_va, tpte); 1984 } 1985#endif 1986 if (pmap_track_modified(pv->pv_va)) 1987 vm_page_dirty(m); 1988 } 1989 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1990 1991 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1992 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1993 m->md.pv_list_count--; 1994 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1995 free_pv_entry(pv); 1996 } 1997 1998 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1999 2000 splx(s); 2001} 2002 2003/* 2004 * Set the physical protection on the 2005 * specified range of this map as requested. 2006 */ 2007void 2008pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 2009{ 2010 register pt_entry_t *ptbase; 2011 vm_offset_t pdnxt; 2012 pd_entry_t ptpaddr; 2013 vm_pindex_t sindex, eindex; 2014 int anychanged; 2015 2016 if (pmap == NULL) 2017 return; 2018 2019 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 2020 pmap_remove(pmap, sva, eva); 2021 return; 2022 } 2023 2024 if (prot & VM_PROT_WRITE) 2025 return; 2026 2027 anychanged = 0; 2028 2029 ptbase = get_ptbase(pmap); 2030 2031 sindex = i386_btop(sva); 2032 eindex = i386_btop(eva); 2033 2034 for (; sindex < eindex; sindex = pdnxt) { 2035 2036 unsigned pdirindex; 2037 2038 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 2039 2040 pdirindex = sindex / NPDEPG; 2041 ptpaddr = pmap->pm_pdir[pdirindex]; 2042 if ((ptpaddr & PG_PS) != 0) { 2043 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 2044 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 2045 anychanged++; 2046 continue; 2047 } 2048 2049 /* 2050 * Weed out invalid mappings. Note: we assume that the page 2051 * directory table is always allocated, and in kernel virtual. 2052 */ 2053 if (ptpaddr == 0) 2054 continue; 2055 2056 if (pdnxt > eindex) { 2057 pdnxt = eindex; 2058 } 2059 2060 for (; sindex != pdnxt; sindex++) { 2061 2062 pt_entry_t pbits; 2063 vm_page_t m; 2064 2065 pbits = ptbase[sindex]; 2066 2067 if (pbits & PG_MANAGED) { 2068 m = NULL; 2069 if (pbits & PG_A) { 2070 m = PHYS_TO_VM_PAGE(pbits); 2071 vm_page_flag_set(m, PG_REFERENCED); 2072 pbits &= ~PG_A; 2073 } 2074 if (pbits & PG_M) { 2075 if (pmap_track_modified(i386_ptob(sindex))) { 2076 if (m == NULL) 2077 m = PHYS_TO_VM_PAGE(pbits); 2078 vm_page_dirty(m); 2079 pbits &= ~PG_M; 2080 } 2081 } 2082 } 2083 2084 pbits &= ~PG_RW; 2085 2086 if (pbits != ptbase[sindex]) { 2087 ptbase[sindex] = pbits; 2088 anychanged = 1; 2089 } 2090 } 2091 } 2092 if (anychanged) 2093 pmap_invalidate_all(pmap); 2094} 2095 2096/* 2097 * Insert the given physical page (p) at 2098 * the specified virtual address (v) in the 2099 * target physical map with the protection requested. 2100 * 2101 * If specified, the page will be wired down, meaning 2102 * that the related pte can not be reclaimed. 2103 * 2104 * NB: This is the only routine which MAY NOT lazy-evaluate 2105 * or lose information. That is, this routine must actually 2106 * insert this page into the given map NOW. 2107 */ 2108void 2109pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2110 boolean_t wired) 2111{ 2112 vm_offset_t pa; 2113 register pt_entry_t *pte; 2114 vm_offset_t opa; 2115 pt_entry_t origpte, newpte; 2116 vm_page_t mpte; 2117 2118 if (pmap == NULL) 2119 return; 2120 2121 va &= PG_FRAME; 2122#ifdef PMAP_DIAGNOSTIC 2123 if (va > VM_MAX_KERNEL_ADDRESS) 2124 panic("pmap_enter: toobig"); 2125 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2126 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2127#endif 2128 2129 mpte = NULL; 2130 /* 2131 * In the case that a page table page is not 2132 * resident, we are creating it here. 2133 */ 2134 if (va < VM_MAXUSER_ADDRESS) { 2135 mpte = pmap_allocpte(pmap, va); 2136 } 2137#if 0 && defined(PMAP_DIAGNOSTIC) 2138 else { 2139 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2140 origpte = *pdeaddr; 2141 if ((origpte & PG_V) == 0) { 2142 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2143 pmap->pm_pdir[PTDPTDI], origpte, va); 2144 } 2145 } 2146#endif 2147 2148 pte = pmap_pte(pmap, va); 2149 2150 /* 2151 * Page Directory table entry not valid, we need a new PT page 2152 */ 2153 if (pte == NULL) { 2154 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2155 (void *)pmap->pm_pdir[PTDPTDI], va); 2156 } 2157 2158 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2159 origpte = *(vm_offset_t *)pte; 2160 opa = origpte & PG_FRAME; 2161 2162 if (origpte & PG_PS) 2163 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2164 2165 /* 2166 * Mapping has not changed, must be protection or wiring change. 2167 */ 2168 if (origpte && (opa == pa)) { 2169 /* 2170 * Wiring change, just update stats. We don't worry about 2171 * wiring PT pages as they remain resident as long as there 2172 * are valid mappings in them. Hence, if a user page is wired, 2173 * the PT page will be also. 2174 */ 2175 if (wired && ((origpte & PG_W) == 0)) 2176 pmap->pm_stats.wired_count++; 2177 else if (!wired && (origpte & PG_W)) 2178 pmap->pm_stats.wired_count--; 2179 2180#if defined(PMAP_DIAGNOSTIC) 2181 if (pmap_nw_modified((pt_entry_t) origpte)) { 2182 printf( 2183 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2184 va, origpte); 2185 } 2186#endif 2187 2188 /* 2189 * Remove extra pte reference 2190 */ 2191 if (mpte) 2192 mpte->hold_count--; 2193 2194 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2195 if ((origpte & PG_RW) == 0) { 2196 *pte |= PG_RW; 2197#ifdef SMP 2198 cpu_invlpg((void *)va); 2199 if (pmap->pm_active & PCPU_GET(other_cpus)) 2200 smp_invltlb(); 2201#else 2202 invltlb_1pg(va); 2203#endif 2204 } 2205 return; 2206 } 2207 2208 /* 2209 * We might be turning off write access to the page, 2210 * so we go ahead and sense modify status. 2211 */ 2212 if (origpte & PG_MANAGED) { 2213 if ((origpte & PG_M) && pmap_track_modified(va)) { 2214 vm_page_t om; 2215 om = PHYS_TO_VM_PAGE(opa); 2216 vm_page_dirty(om); 2217 } 2218 pa |= PG_MANAGED; 2219 } 2220 goto validate; 2221 } 2222 /* 2223 * Mapping has changed, invalidate old range and fall through to 2224 * handle validating new mapping. 2225 */ 2226 if (opa) { 2227 int err; 2228 err = pmap_remove_pte(pmap, pte, va); 2229 if (err) 2230 panic("pmap_enter: pte vanished, va: 0x%x", va); 2231 } 2232 2233 /* 2234 * Enter on the PV list if part of our managed memory. Note that we 2235 * raise IPL while manipulating pv_table since pmap_enter can be 2236 * called at interrupt time. 2237 */ 2238 if (pmap_initialized && 2239 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2240 pmap_insert_entry(pmap, va, mpte, m); 2241 pa |= PG_MANAGED; 2242 } 2243 2244 /* 2245 * Increment counters 2246 */ 2247 pmap->pm_stats.resident_count++; 2248 if (wired) 2249 pmap->pm_stats.wired_count++; 2250 2251validate: 2252 /* 2253 * Now validate mapping with desired protection/wiring. 2254 */ 2255 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2256 2257 if (wired) 2258 newpte |= PG_W; 2259 if (va < VM_MAXUSER_ADDRESS) 2260 newpte |= PG_U; 2261 if (pmap == kernel_pmap) 2262 newpte |= pgeflag; 2263 2264 /* 2265 * if the mapping or permission bits are different, we need 2266 * to update the pte. 2267 */ 2268 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2269 *pte = newpte | PG_A; 2270 /*if (origpte)*/ { 2271#ifdef SMP 2272 cpu_invlpg((void *)va); 2273 if (pmap->pm_active & PCPU_GET(other_cpus)) 2274 smp_invltlb(); 2275#else 2276 invltlb_1pg(va); 2277#endif 2278 } 2279 } 2280} 2281 2282/* 2283 * this code makes some *MAJOR* assumptions: 2284 * 1. Current pmap & pmap exists. 2285 * 2. Not wired. 2286 * 3. Read access. 2287 * 4. No page table pages. 2288 * 5. Tlbflush is deferred to calling procedure. 2289 * 6. Page IS managed. 2290 * but is *MUCH* faster than pmap_enter... 2291 */ 2292 2293static vm_page_t 2294pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2295{ 2296 pt_entry_t *pte; 2297 vm_offset_t pa; 2298 2299 /* 2300 * In the case that a page table page is not 2301 * resident, we are creating it here. 2302 */ 2303 if (va < VM_MAXUSER_ADDRESS) { 2304 unsigned ptepindex; 2305 pd_entry_t ptepa; 2306 2307 /* 2308 * Calculate pagetable page index 2309 */ 2310 ptepindex = va >> PDRSHIFT; 2311 if (mpte && (mpte->pindex == ptepindex)) { 2312 mpte->hold_count++; 2313 } else { 2314retry: 2315 /* 2316 * Get the page directory entry 2317 */ 2318 ptepa = pmap->pm_pdir[ptepindex]; 2319 2320 /* 2321 * If the page table page is mapped, we just increment 2322 * the hold count, and activate it. 2323 */ 2324 if (ptepa) { 2325 if (ptepa & PG_PS) 2326 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2327 if (pmap->pm_ptphint && 2328 (pmap->pm_ptphint->pindex == ptepindex)) { 2329 mpte = pmap->pm_ptphint; 2330 } else { 2331 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2332 pmap->pm_ptphint = mpte; 2333 } 2334 if (mpte == NULL) 2335 goto retry; 2336 mpte->hold_count++; 2337 } else { 2338 mpte = _pmap_allocpte(pmap, ptepindex); 2339 } 2340 } 2341 } else { 2342 mpte = NULL; 2343 } 2344 2345 /* 2346 * This call to vtopte makes the assumption that we are 2347 * entering the page into the current pmap. In order to support 2348 * quick entry into any pmap, one would likely use pmap_pte_quick. 2349 * But that isn't as quick as vtopte. 2350 */ 2351 pte = vtopte(va); 2352 if (*pte) { 2353 if (mpte) 2354 pmap_unwire_pte_hold(pmap, mpte); 2355 return 0; 2356 } 2357 2358 /* 2359 * Enter on the PV list if part of our managed memory. Note that we 2360 * raise IPL while manipulating pv_table since pmap_enter can be 2361 * called at interrupt time. 2362 */ 2363 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2364 pmap_insert_entry(pmap, va, mpte, m); 2365 2366 /* 2367 * Increment counters 2368 */ 2369 pmap->pm_stats.resident_count++; 2370 2371 pa = VM_PAGE_TO_PHYS(m); 2372 2373 /* 2374 * Now validate mapping with RO protection 2375 */ 2376 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2377 *pte = pa | PG_V | PG_U; 2378 else 2379 *pte = pa | PG_V | PG_U | PG_MANAGED; 2380 2381 return mpte; 2382} 2383 2384/* 2385 * Make a temporary mapping for a physical address. This is only intended 2386 * to be used for panic dumps. 2387 */ 2388void * 2389pmap_kenter_temporary(vm_offset_t pa, int i) 2390{ 2391 pmap_kenter((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa); 2392 return ((void *)crashdumpmap); 2393} 2394 2395#define MAX_INIT_PT (96) 2396/* 2397 * pmap_object_init_pt preloads the ptes for a given object 2398 * into the specified pmap. This eliminates the blast of soft 2399 * faults on process startup and immediately after an mmap. 2400 */ 2401void 2402pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2403 vm_object_t object, vm_pindex_t pindex, 2404 vm_size_t size, int limit) 2405{ 2406 vm_offset_t tmpidx; 2407 int psize; 2408 vm_page_t p, mpte; 2409 int objpgs; 2410 2411 if (pmap == NULL || object == NULL) 2412 return; 2413 2414 /* 2415 * This code maps large physical mmap regions into the 2416 * processor address space. Note that some shortcuts 2417 * are taken, but the code works. 2418 */ 2419 if (pseflag && (object->type == OBJT_DEVICE) && 2420 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2421 int i; 2422 vm_page_t m[1]; 2423 unsigned int ptepindex; 2424 int npdes; 2425 pd_entry_t ptepa; 2426 2427 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2428 return; 2429 2430retry: 2431 p = vm_page_lookup(object, pindex); 2432 if (p && vm_page_sleep_busy(p, FALSE, "init4p")) 2433 goto retry; 2434 2435 if (p == NULL) { 2436 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2437 if (p == NULL) 2438 return; 2439 m[0] = p; 2440 2441 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2442 vm_page_free(p); 2443 return; 2444 } 2445 2446 p = vm_page_lookup(object, pindex); 2447 vm_page_wakeup(p); 2448 } 2449 2450 ptepa = VM_PAGE_TO_PHYS(p); 2451 if (ptepa & (NBPDR - 1)) { 2452 return; 2453 } 2454 2455 p->valid = VM_PAGE_BITS_ALL; 2456 2457 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2458 npdes = size >> PDRSHIFT; 2459 for(i = 0; i < npdes; i++) { 2460 pmap->pm_pdir[ptepindex] = 2461 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2462 ptepa += NBPDR; 2463 ptepindex += 1; 2464 } 2465 vm_page_flag_set(p, PG_MAPPED); 2466 invltlb(); 2467 return; 2468 } 2469 2470 psize = i386_btop(size); 2471 2472 if ((object->type != OBJT_VNODE) || 2473 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2474 (object->resident_page_count > MAX_INIT_PT))) { 2475 return; 2476 } 2477 2478 if (psize + pindex > object->size) { 2479 if (object->size < pindex) 2480 return; 2481 psize = object->size - pindex; 2482 } 2483 2484 mpte = NULL; 2485 /* 2486 * if we are processing a major portion of the object, then scan the 2487 * entire thing. 2488 */ 2489 if (psize > (object->resident_page_count >> 2)) { 2490 objpgs = psize; 2491 2492 for (p = TAILQ_FIRST(&object->memq); 2493 ((objpgs > 0) && (p != NULL)); 2494 p = TAILQ_NEXT(p, listq)) { 2495 2496 tmpidx = p->pindex; 2497 if (tmpidx < pindex) { 2498 continue; 2499 } 2500 tmpidx -= pindex; 2501 if (tmpidx >= psize) { 2502 continue; 2503 } 2504 /* 2505 * don't allow an madvise to blow away our really 2506 * free pages allocating pv entries. 2507 */ 2508 if ((limit & MAP_PREFAULT_MADVISE) && 2509 cnt.v_free_count < cnt.v_free_reserved) { 2510 break; 2511 } 2512 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2513 (p->busy == 0) && 2514 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2515 if ((p->queue - p->pc) == PQ_CACHE) 2516 vm_page_deactivate(p); 2517 vm_page_busy(p); 2518 mpte = pmap_enter_quick(pmap, 2519 addr + i386_ptob(tmpidx), p, mpte); 2520 vm_page_flag_set(p, PG_MAPPED); 2521 vm_page_wakeup(p); 2522 } 2523 objpgs -= 1; 2524 } 2525 } else { 2526 /* 2527 * else lookup the pages one-by-one. 2528 */ 2529 for (tmpidx = 0; tmpidx < psize; tmpidx += 1) { 2530 /* 2531 * don't allow an madvise to blow away our really 2532 * free pages allocating pv entries. 2533 */ 2534 if ((limit & MAP_PREFAULT_MADVISE) && 2535 cnt.v_free_count < cnt.v_free_reserved) { 2536 break; 2537 } 2538 p = vm_page_lookup(object, tmpidx + pindex); 2539 if (p && 2540 ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2541 (p->busy == 0) && 2542 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2543 if ((p->queue - p->pc) == PQ_CACHE) 2544 vm_page_deactivate(p); 2545 vm_page_busy(p); 2546 mpte = pmap_enter_quick(pmap, 2547 addr + i386_ptob(tmpidx), p, mpte); 2548 vm_page_flag_set(p, PG_MAPPED); 2549 vm_page_wakeup(p); 2550 } 2551 } 2552 } 2553 return; 2554} 2555 2556/* 2557 * pmap_prefault provides a quick way of clustering 2558 * pagefaults into a processes address space. It is a "cousin" 2559 * of pmap_object_init_pt, except it runs at page fault time instead 2560 * of mmap time. 2561 */ 2562#define PFBAK 4 2563#define PFFOR 4 2564#define PAGEORDER_SIZE (PFBAK+PFFOR) 2565 2566static int pmap_prefault_pageorder[] = { 2567 -PAGE_SIZE, PAGE_SIZE, 2568 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2569 -3 * PAGE_SIZE, 3 * PAGE_SIZE 2570 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2571}; 2572 2573void 2574pmap_prefault(pmap, addra, entry) 2575 pmap_t pmap; 2576 vm_offset_t addra; 2577 vm_map_entry_t entry; 2578{ 2579 int i; 2580 vm_offset_t starta; 2581 vm_offset_t addr; 2582 vm_pindex_t pindex; 2583 vm_page_t m, mpte; 2584 vm_object_t object; 2585 2586 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2587 return; 2588 2589 object = entry->object.vm_object; 2590 2591 starta = addra - PFBAK * PAGE_SIZE; 2592 if (starta < entry->start) { 2593 starta = entry->start; 2594 } else if (starta > addra) { 2595 starta = 0; 2596 } 2597 2598 mpte = NULL; 2599 for (i = 0; i < PAGEORDER_SIZE; i++) { 2600 vm_object_t lobject; 2601 pt_entry_t *pte; 2602 2603 addr = addra + pmap_prefault_pageorder[i]; 2604 if (addr > addra + (PFFOR * PAGE_SIZE)) 2605 addr = 0; 2606 2607 if (addr < starta || addr >= entry->end) 2608 continue; 2609 2610 if ((*pmap_pde(pmap, addr)) == NULL) 2611 continue; 2612 2613 pte = vtopte(addr); 2614 if (*pte) 2615 continue; 2616 2617 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2618 lobject = object; 2619 for (m = vm_page_lookup(lobject, pindex); 2620 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2621 lobject = lobject->backing_object) { 2622 if (lobject->backing_object_offset & PAGE_MASK) 2623 break; 2624 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2625 m = vm_page_lookup(lobject->backing_object, pindex); 2626 } 2627 2628 /* 2629 * give-up when a page is not in memory 2630 */ 2631 if (m == NULL) 2632 break; 2633 2634 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2635 (m->busy == 0) && 2636 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2637 2638 if ((m->queue - m->pc) == PQ_CACHE) { 2639 vm_page_deactivate(m); 2640 } 2641 vm_page_busy(m); 2642 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2643 vm_page_flag_set(m, PG_MAPPED); 2644 vm_page_wakeup(m); 2645 } 2646 } 2647} 2648 2649/* 2650 * Routine: pmap_change_wiring 2651 * Function: Change the wiring attribute for a map/virtual-address 2652 * pair. 2653 * In/out conditions: 2654 * The mapping must already exist in the pmap. 2655 */ 2656void 2657pmap_change_wiring(pmap, va, wired) 2658 register pmap_t pmap; 2659 vm_offset_t va; 2660 boolean_t wired; 2661{ 2662 register pt_entry_t *pte; 2663 2664 if (pmap == NULL) 2665 return; 2666 2667 pte = pmap_pte(pmap, va); 2668 2669 if (wired && !pmap_pte_w(pte)) 2670 pmap->pm_stats.wired_count++; 2671 else if (!wired && pmap_pte_w(pte)) 2672 pmap->pm_stats.wired_count--; 2673 2674 /* 2675 * Wiring is not a hardware characteristic so there is no need to 2676 * invalidate TLB. 2677 */ 2678 pmap_pte_set_w(pte, wired); 2679} 2680 2681 2682 2683/* 2684 * Copy the range specified by src_addr/len 2685 * from the source map to the range dst_addr/len 2686 * in the destination map. 2687 * 2688 * This routine is only advisory and need not do anything. 2689 */ 2690 2691void 2692pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2693 vm_offset_t src_addr) 2694{ 2695 vm_offset_t addr; 2696 vm_offset_t end_addr = src_addr + len; 2697 vm_offset_t pdnxt; 2698 pd_entry_t src_frame, dst_frame; 2699 vm_page_t m; 2700 pd_entry_t saved_pde; 2701 2702 if (dst_addr != src_addr) 2703 return; 2704 2705 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2706 if (src_frame != (PTDpde & PG_FRAME)) 2707 return; 2708 2709 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2710 if (dst_frame != (APTDpde & PG_FRAME)) { 2711 APTDpde = dst_frame | PG_RW | PG_V; 2712#if defined(SMP) 2713 /* The page directory is not shared between CPUs */ 2714 cpu_invltlb(); 2715#else 2716 invltlb(); 2717#endif 2718 } 2719 saved_pde = APTDpde & (PG_FRAME | PG_RW | PG_V); 2720 for(addr = src_addr; addr < end_addr; addr = pdnxt) { 2721 pt_entry_t *src_pte, *dst_pte; 2722 vm_page_t dstmpte, srcmpte; 2723 pd_entry_t srcptepaddr; 2724 unsigned ptepindex; 2725 2726 if (addr >= UPT_MIN_ADDRESS) 2727 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2728 2729 /* 2730 * Don't let optional prefaulting of pages make us go 2731 * way below the low water mark of free pages or way 2732 * above high water mark of used pv entries. 2733 */ 2734 if (cnt.v_free_count < cnt.v_free_reserved || 2735 pv_entry_count > pv_entry_high_water) 2736 break; 2737 2738 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2739 ptepindex = addr >> PDRSHIFT; 2740 2741 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2742 if (srcptepaddr == 0) 2743 continue; 2744 2745 if (srcptepaddr & PG_PS) { 2746 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2747 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2748 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2749 } 2750 continue; 2751 } 2752 2753 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2754 if ((srcmpte == NULL) || 2755 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2756 continue; 2757 2758 if (pdnxt > end_addr) 2759 pdnxt = end_addr; 2760 2761 src_pte = vtopte(addr); 2762 dst_pte = avtopte(addr); 2763 while (addr < pdnxt) { 2764 pt_entry_t ptetemp; 2765 ptetemp = *src_pte; 2766 /* 2767 * we only virtual copy managed pages 2768 */ 2769 if ((ptetemp & PG_MANAGED) != 0) { 2770 /* 2771 * We have to check after allocpte for the 2772 * pte still being around... allocpte can 2773 * block. 2774 */ 2775 dstmpte = pmap_allocpte(dst_pmap, addr); 2776 if ((APTDpde & PG_FRAME) != 2777 (saved_pde & PG_FRAME)) { 2778 APTDpde = saved_pde; 2779printf ("IT HAPPENNED!"); 2780#if defined(SMP) 2781 cpu_invltlb(); 2782#else 2783 invltlb(); 2784#endif 2785 } 2786 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2787 /* 2788 * Clear the modified and 2789 * accessed (referenced) bits 2790 * during the copy. 2791 */ 2792 m = PHYS_TO_VM_PAGE(ptetemp); 2793 *dst_pte = ptetemp & ~(PG_M | PG_A); 2794 dst_pmap->pm_stats.resident_count++; 2795 pmap_insert_entry(dst_pmap, addr, 2796 dstmpte, m); 2797 } else { 2798 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2799 } 2800 if (dstmpte->hold_count >= srcmpte->hold_count) 2801 break; 2802 } 2803 addr += PAGE_SIZE; 2804 src_pte++; 2805 dst_pte++; 2806 } 2807 } 2808} 2809 2810/* 2811 * pmap_zero_page zeros the specified hardware page by mapping 2812 * the page into KVM and using bzero to clear its contents. 2813 */ 2814void 2815pmap_zero_page(vm_page_t m) 2816{ 2817 vm_offset_t phys = VM_PAGE_TO_PHYS(m); 2818 2819 if (*CMAP2) 2820 panic("pmap_zero_page: CMAP2 busy"); 2821 2822 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2823 invltlb_1pg((vm_offset_t)CADDR2); 2824 2825#if defined(I686_CPU) 2826 if (cpu_class == CPUCLASS_686) 2827 i686_pagezero(CADDR2); 2828 else 2829#endif 2830 bzero(CADDR2, PAGE_SIZE); 2831 *CMAP2 = 0; 2832} 2833 2834/* 2835 * pmap_zero_page_area zeros the specified hardware page by mapping 2836 * the page into KVM and using bzero to clear its contents. 2837 * 2838 * off and size may not cover an area beyond a single hardware page. 2839 */ 2840void 2841pmap_zero_page_area(vm_page_t m, int off, int size) 2842{ 2843 vm_offset_t phys = VM_PAGE_TO_PHYS(m); 2844 2845 if (*CMAP2) 2846 panic("pmap_zero_page: CMAP2 busy"); 2847 2848 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2849 invltlb_1pg((vm_offset_t)CADDR2); 2850 2851#if defined(I686_CPU) 2852 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2853 i686_pagezero(CADDR2); 2854 else 2855#endif 2856 bzero((char *)CADDR2 + off, size); 2857 *CMAP2 = 0; 2858} 2859 2860/* 2861 * pmap_copy_page copies the specified (machine independent) 2862 * page by mapping the page into virtual memory and using 2863 * bcopy to copy the page, one machine dependent page at a 2864 * time. 2865 */ 2866void 2867pmap_copy_page(vm_page_t src, vm_page_t dst) 2868{ 2869 2870 if (*CMAP1) 2871 panic("pmap_copy_page: CMAP1 busy"); 2872 if (*CMAP2) 2873 panic("pmap_copy_page: CMAP2 busy"); 2874 2875 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2876 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2877#ifdef I386_CPU 2878 invltlb(); 2879#else 2880 invlpg((u_int)CADDR1); 2881 invlpg((u_int)CADDR2); 2882#endif 2883 2884 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2885 2886 *CMAP1 = 0; 2887 *CMAP2 = 0; 2888} 2889 2890 2891/* 2892 * Routine: pmap_pageable 2893 * Function: 2894 * Make the specified pages (by pmap, offset) 2895 * pageable (or not) as requested. 2896 * 2897 * A page which is not pageable may not take 2898 * a fault; therefore, its page table entry 2899 * must remain valid for the duration. 2900 * 2901 * This routine is merely advisory; pmap_enter 2902 * will specify that these pages are to be wired 2903 * down (or not) as appropriate. 2904 */ 2905void 2906pmap_pageable(pmap, sva, eva, pageable) 2907 pmap_t pmap; 2908 vm_offset_t sva, eva; 2909 boolean_t pageable; 2910{ 2911} 2912 2913/* 2914 * Returns true if the pmap's pv is one of the first 2915 * 16 pvs linked to from this page. This count may 2916 * be changed upwards or downwards in the future; it 2917 * is only necessary that true be returned for a small 2918 * subset of pmaps for proper page aging. 2919 */ 2920boolean_t 2921pmap_page_exists_quick(pmap, m) 2922 pmap_t pmap; 2923 vm_page_t m; 2924{ 2925 pv_entry_t pv; 2926 int loops = 0; 2927 int s; 2928 2929 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2930 return FALSE; 2931 2932 s = splvm(); 2933 2934 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2935 if (pv->pv_pmap == pmap) { 2936 splx(s); 2937 return TRUE; 2938 } 2939 loops++; 2940 if (loops >= 16) 2941 break; 2942 } 2943 splx(s); 2944 return (FALSE); 2945} 2946 2947#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2948/* 2949 * Remove all pages from specified address space 2950 * this aids process exit speeds. Also, this code 2951 * is special cased for current process only, but 2952 * can have the more generic (and slightly slower) 2953 * mode enabled. This is much faster than pmap_remove 2954 * in the case of running down an entire address space. 2955 */ 2956void 2957pmap_remove_pages(pmap, sva, eva) 2958 pmap_t pmap; 2959 vm_offset_t sva, eva; 2960{ 2961 pt_entry_t *pte, tpte; 2962 vm_page_t m; 2963 pv_entry_t pv, npv; 2964 int s; 2965 2966#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2967 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2968 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2969 return; 2970 } 2971#endif 2972 2973 s = splvm(); 2974 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2975 2976 if (pv->pv_va >= eva || pv->pv_va < sva) { 2977 npv = TAILQ_NEXT(pv, pv_plist); 2978 continue; 2979 } 2980 2981#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2982 pte = vtopte(pv->pv_va); 2983#else 2984 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2985#endif 2986 tpte = *pte; 2987 2988 if (tpte == 0) { 2989 printf("TPTE at %p IS ZERO @ VA %08x\n", 2990 pte, pv->pv_va); 2991 panic("bad pte"); 2992 } 2993 2994/* 2995 * We cannot remove wired pages from a process' mapping at this time 2996 */ 2997 if (tpte & PG_W) { 2998 npv = TAILQ_NEXT(pv, pv_plist); 2999 continue; 3000 } 3001 3002 m = PHYS_TO_VM_PAGE(tpte); 3003 KASSERT(m->phys_addr == (tpte & PG_FRAME), 3004 ("vm_page_t %p phys_addr mismatch %08x %08x", 3005 m, m->phys_addr, tpte)); 3006 3007 KASSERT(m < &vm_page_array[vm_page_array_size], 3008 ("pmap_remove_pages: bad tpte %x", tpte)); 3009 3010 pv->pv_pmap->pm_stats.resident_count--; 3011 3012 *pte = 0; 3013 3014 /* 3015 * Update the vm_page_t clean and reference bits. 3016 */ 3017 if (tpte & PG_M) { 3018 vm_page_dirty(m); 3019 } 3020 3021 npv = TAILQ_NEXT(pv, pv_plist); 3022 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 3023 3024 m->md.pv_list_count--; 3025 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3026 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 3027 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 3028 } 3029 3030 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 3031 free_pv_entry(pv); 3032 } 3033 splx(s); 3034 pmap_invalidate_all(pmap); 3035} 3036 3037/* 3038 * pmap_testbit tests bits in pte's 3039 * note that the testbit/changebit routines are inline, 3040 * and a lot of things compile-time evaluate. 3041 */ 3042static boolean_t 3043pmap_testbit(m, bit) 3044 vm_page_t m; 3045 int bit; 3046{ 3047 pv_entry_t pv; 3048 pt_entry_t *pte; 3049 int s; 3050 3051 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3052 return FALSE; 3053 3054 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 3055 return FALSE; 3056 3057 s = splvm(); 3058 3059 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3060 /* 3061 * if the bit being tested is the modified bit, then 3062 * mark clean_map and ptes as never 3063 * modified. 3064 */ 3065 if (bit & (PG_A|PG_M)) { 3066 if (!pmap_track_modified(pv->pv_va)) 3067 continue; 3068 } 3069 3070#if defined(PMAP_DIAGNOSTIC) 3071 if (!pv->pv_pmap) { 3072 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3073 continue; 3074 } 3075#endif 3076 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3077 if (*pte & bit) { 3078 splx(s); 3079 return TRUE; 3080 } 3081 } 3082 splx(s); 3083 return (FALSE); 3084} 3085 3086/* 3087 * this routine is used to modify bits in ptes 3088 */ 3089static __inline void 3090pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3091{ 3092 register pv_entry_t pv; 3093 register pt_entry_t *pte; 3094 int s; 3095 3096 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3097 return; 3098 3099 s = splvm(); 3100 3101 /* 3102 * Loop over all current mappings setting/clearing as appropos If 3103 * setting RO do we need to clear the VAC? 3104 */ 3105 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3106 /* 3107 * don't write protect pager mappings 3108 */ 3109 if (!setem && (bit == PG_RW)) { 3110 if (!pmap_track_modified(pv->pv_va)) 3111 continue; 3112 } 3113 3114#if defined(PMAP_DIAGNOSTIC) 3115 if (!pv->pv_pmap) { 3116 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3117 continue; 3118 } 3119#endif 3120 3121 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3122 3123 if (setem) { 3124 *pte |= bit; 3125 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3126 } else { 3127 pt_entry_t pbits = *pte; 3128 if (pbits & bit) { 3129 if (bit == PG_RW) { 3130 if (pbits & PG_M) { 3131 vm_page_dirty(m); 3132 } 3133 *pte = pbits & ~(PG_M|PG_RW); 3134 } else { 3135 *pte = pbits & ~bit; 3136 } 3137 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3138 } 3139 } 3140 } 3141 splx(s); 3142} 3143 3144/* 3145 * pmap_page_protect: 3146 * 3147 * Lower the permission for all mappings to a given page. 3148 */ 3149void 3150pmap_page_protect(vm_page_t m, vm_prot_t prot) 3151{ 3152 if ((prot & VM_PROT_WRITE) == 0) { 3153 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3154 pmap_changebit(m, PG_RW, FALSE); 3155 } else { 3156 pmap_remove_all(m); 3157 } 3158 } 3159} 3160 3161vm_offset_t 3162pmap_phys_address(ppn) 3163 int ppn; 3164{ 3165 return (i386_ptob(ppn)); 3166} 3167 3168/* 3169 * pmap_ts_referenced: 3170 * 3171 * Return a count of reference bits for a page, clearing those bits. 3172 * It is not necessary for every reference bit to be cleared, but it 3173 * is necessary that 0 only be returned when there are truly no 3174 * reference bits set. 3175 * 3176 * XXX: The exact number of bits to check and clear is a matter that 3177 * should be tested and standardized at some point in the future for 3178 * optimal aging of shared pages. 3179 */ 3180int 3181pmap_ts_referenced(vm_page_t m) 3182{ 3183 register pv_entry_t pv, pvf, pvn; 3184 pt_entry_t *pte; 3185 int s; 3186 int rtval = 0; 3187 3188 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3189 return (rtval); 3190 3191 s = splvm(); 3192 3193 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3194 3195 pvf = pv; 3196 3197 do { 3198 pvn = TAILQ_NEXT(pv, pv_list); 3199 3200 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3201 3202 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3203 3204 if (!pmap_track_modified(pv->pv_va)) 3205 continue; 3206 3207 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3208 3209 if (pte && (*pte & PG_A)) { 3210 *pte &= ~PG_A; 3211 3212 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3213 3214 rtval++; 3215 if (rtval > 4) { 3216 break; 3217 } 3218 } 3219 } while ((pv = pvn) != NULL && pv != pvf); 3220 } 3221 splx(s); 3222 3223 return (rtval); 3224} 3225 3226/* 3227 * pmap_is_modified: 3228 * 3229 * Return whether or not the specified physical page was modified 3230 * in any physical maps. 3231 */ 3232boolean_t 3233pmap_is_modified(vm_page_t m) 3234{ 3235 return pmap_testbit(m, PG_M); 3236} 3237 3238/* 3239 * Clear the modify bits on the specified physical page. 3240 */ 3241void 3242pmap_clear_modify(vm_page_t m) 3243{ 3244 pmap_changebit(m, PG_M, FALSE); 3245} 3246 3247/* 3248 * pmap_clear_reference: 3249 * 3250 * Clear the reference bit on the specified physical page. 3251 */ 3252void 3253pmap_clear_reference(vm_page_t m) 3254{ 3255 pmap_changebit(m, PG_A, FALSE); 3256} 3257 3258/* 3259 * Miscellaneous support routines follow 3260 */ 3261 3262static void 3263i386_protection_init() 3264{ 3265 register int *kp, prot; 3266 3267 kp = protection_codes; 3268 for (prot = 0; prot < 8; prot++) { 3269 switch (prot) { 3270 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3271 /* 3272 * Read access is also 0. There isn't any execute bit, 3273 * so just make it readable. 3274 */ 3275 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3276 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3277 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3278 *kp++ = 0; 3279 break; 3280 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3281 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3282 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3283 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3284 *kp++ = PG_RW; 3285 break; 3286 } 3287 } 3288} 3289 3290/* 3291 * Map a set of physical memory pages into the kernel virtual 3292 * address space. Return a pointer to where it is mapped. This 3293 * routine is intended to be used for mapping device memory, 3294 * NOT real memory. 3295 */ 3296void * 3297pmap_mapdev(pa, size) 3298 vm_offset_t pa; 3299 vm_size_t size; 3300{ 3301 vm_offset_t va, tmpva, offset; 3302 pt_entry_t *pte; 3303 3304 offset = pa & PAGE_MASK; 3305 size = roundup(offset + size, PAGE_SIZE); 3306 3307 GIANT_REQUIRED; 3308 3309 va = kmem_alloc_pageable(kernel_map, size); 3310 if (!va) 3311 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3312 3313 pa = pa & PG_FRAME; 3314 for (tmpva = va; size > 0;) { 3315 pte = vtopte(tmpva); 3316 *pte = pa | PG_RW | PG_V | pgeflag; 3317 size -= PAGE_SIZE; 3318 tmpva += PAGE_SIZE; 3319 pa += PAGE_SIZE; 3320 } 3321 invltlb(); 3322 3323 return ((void *)(va + offset)); 3324} 3325 3326void 3327pmap_unmapdev(va, size) 3328 vm_offset_t va; 3329 vm_size_t size; 3330{ 3331 vm_offset_t base, offset; 3332 3333 base = va & PG_FRAME; 3334 offset = va & PAGE_MASK; 3335 size = roundup(offset + size, PAGE_SIZE); 3336 kmem_free(kernel_map, base, size); 3337} 3338 3339/* 3340 * perform the pmap work for mincore 3341 */ 3342int 3343pmap_mincore(pmap, addr) 3344 pmap_t pmap; 3345 vm_offset_t addr; 3346{ 3347 pt_entry_t *ptep, pte; 3348 vm_page_t m; 3349 int val = 0; 3350 3351 ptep = pmap_pte(pmap, addr); 3352 if (ptep == 0) { 3353 return 0; 3354 } 3355 3356 if ((pte = *ptep) != 0) { 3357 vm_offset_t pa; 3358 3359 val = MINCORE_INCORE; 3360 if ((pte & PG_MANAGED) == 0) 3361 return val; 3362 3363 pa = pte & PG_FRAME; 3364 3365 m = PHYS_TO_VM_PAGE(pa); 3366 3367 /* 3368 * Modified by us 3369 */ 3370 if (pte & PG_M) 3371 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3372 /* 3373 * Modified by someone 3374 */ 3375 else if (m->dirty || pmap_is_modified(m)) 3376 val |= MINCORE_MODIFIED_OTHER; 3377 /* 3378 * Referenced by us 3379 */ 3380 if (pte & PG_A) 3381 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3382 3383 /* 3384 * Referenced by someone 3385 */ 3386 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3387 val |= MINCORE_REFERENCED_OTHER; 3388 vm_page_flag_set(m, PG_REFERENCED); 3389 } 3390 } 3391 return val; 3392} 3393 3394void 3395pmap_activate(struct thread *td) 3396{ 3397 struct proc *p = td->td_proc; 3398 pmap_t pmap; 3399 u_int32_t cr3; 3400 3401 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3402#if defined(SMP) 3403 pmap->pm_active |= PCPU_GET(cpumask); 3404#else 3405 pmap->pm_active |= 1; 3406#endif 3407#if defined(SWTCH_OPTIM_STATS) 3408 tlb_flush_count++; 3409#endif 3410 cr3 = vtophys(pmap->pm_pdir); 3411 /* XXXKSE this is wrong. 3412 * pmap_activate is for the current thread on the current cpu 3413 */ 3414 if (p->p_flag & P_KSES) { 3415 /* Make sure all other cr3 entries are updated. */ 3416 /* what if they are running? XXXKSE (maybe abort them) */ 3417 FOREACH_THREAD_IN_PROC(p, td) { 3418 td->td_pcb->pcb_cr3 = cr3; 3419 } 3420 } else { 3421 td->td_pcb->pcb_cr3 = cr3; 3422 } 3423 load_cr3(cr3); 3424} 3425 3426vm_offset_t 3427pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3428{ 3429 3430 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3431 return addr; 3432 } 3433 3434 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3435 return addr; 3436} 3437 3438 3439#if defined(PMAP_DEBUG) 3440pmap_pid_dump(int pid) 3441{ 3442 pmap_t pmap; 3443 struct proc *p; 3444 int npte = 0; 3445 int index; 3446 3447 sx_slock(&allproc_lock); 3448 LIST_FOREACH(p, &allproc, p_list) { 3449 if (p->p_pid != pid) 3450 continue; 3451 3452 if (p->p_vmspace) { 3453 int i,j; 3454 index = 0; 3455 pmap = vmspace_pmap(p->p_vmspace); 3456 for (i = 0; i < NPDEPG; i++) { 3457 pd_entry_t *pde; 3458 pt_entry_t *pte; 3459 vm_offset_t base = i << PDRSHIFT; 3460 3461 pde = &pmap->pm_pdir[i]; 3462 if (pde && pmap_pde_v(pde)) { 3463 for (j = 0; j < NPTEPG; j++) { 3464 vm_offset_t va = base + (j << PAGE_SHIFT); 3465 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3466 if (index) { 3467 index = 0; 3468 printf("\n"); 3469 } 3470 sx_sunlock(&allproc_lock); 3471 return npte; 3472 } 3473 pte = pmap_pte_quick(pmap, va); 3474 if (pte && pmap_pte_v(pte)) { 3475 pt_entry_t pa; 3476 vm_page_t m; 3477 pa = *pte; 3478 m = PHYS_TO_VM_PAGE(pa); 3479 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3480 va, pa, m->hold_count, m->wire_count, m->flags); 3481 npte++; 3482 index++; 3483 if (index >= 2) { 3484 index = 0; 3485 printf("\n"); 3486 } else { 3487 printf(" "); 3488 } 3489 } 3490 } 3491 } 3492 } 3493 } 3494 } 3495 sx_sunlock(&allproc_lock); 3496 return npte; 3497} 3498#endif 3499 3500#if defined(DEBUG) 3501 3502static void pads(pmap_t pm); 3503void pmap_pvdump(vm_offset_t pa); 3504 3505/* print address space of pmap*/ 3506static void 3507pads(pm) 3508 pmap_t pm; 3509{ 3510 int i, j; 3511 vm_offset_t va; 3512 pt_entry_t *ptep; 3513 3514 if (pm == kernel_pmap) 3515 return; 3516 for (i = 0; i < NPDEPG; i++) 3517 if (pm->pm_pdir[i]) 3518 for (j = 0; j < NPTEPG; j++) { 3519 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3520 if (pm == kernel_pmap && va < KERNBASE) 3521 continue; 3522 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3523 continue; 3524 ptep = pmap_pte_quick(pm, va); 3525 if (pmap_pte_v(ptep)) 3526 printf("%x:%x ", va, *ptep); 3527 }; 3528 3529} 3530 3531void 3532pmap_pvdump(pa) 3533 vm_offset_t pa; 3534{ 3535 pv_entry_t pv; 3536 vm_page_t m; 3537 3538 printf("pa %x", pa); 3539 m = PHYS_TO_VM_PAGE(pa); 3540 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3541 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3542 pads(pv->pv_pmap); 3543 } 3544 printf(" "); 3545} 3546#endif 3547