pmap.c revision 99381
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 99381 2002-07-03 20:47:50Z julian $ 43 */ 44 45/* 46 * Manages physical address maps. 47 * 48 * In addition to hardware address maps, this 49 * module is called upon to provide software-use-only 50 * maps which may or may not be stored in the same 51 * form as hardware maps. These pseudo-maps are 52 * used to store intermediate results from copy 53 * operations to and from address spaces. 54 * 55 * Since the information managed by this module is 56 * also stored by the logical address mapping module, 57 * this module may throw away valid virtual-to-physical 58 * mappings at almost any time. However, invalidations 59 * of virtual-to-physical mappings must be done as 60 * requested. 61 * 62 * In order to cope with hardware architectures which 63 * make virtual-to-physical map invalidates expensive, 64 * this module may delay invalidate or reduced protection 65 * operations until such time as they are actually 66 * necessary. This module is given full information as 67 * to which processors are currently using which maps, 68 * and to when physical maps must be made correct. 69 */ 70 71#include "opt_disable_pse.h" 72#include "opt_pmap.h" 73#include "opt_msgbuf.h" 74#include "opt_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, UMA_ZONE_VM); 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 = vm_object_allocate(OBJT_DEFAULT, KSTACK_PAGES); 1011 td->td_kstack_obj = ksobj; 1012 1013#ifdef KSTACK_GUARD 1014 /* get a kernel virtual address for the kstack for this thread */ 1015 ks = kmem_alloc_nofault(kernel_map, (KSTACK_PAGES + 1) * PAGE_SIZE); 1016 if (ks == 0) 1017 panic("pmap_new_thread: kstack allocation failed"); 1018 1019 /* 1020 * Set the first page to be the unmapped guard page. 1021 */ 1022 ptek = vtopte(ks); 1023 oldpte = *ptek; 1024 *ptek = 0; 1025 if (oldpte) { 1026#ifdef I386_CPU 1027 updateneeded = 1; 1028#else 1029 invlpg(ks); 1030#endif 1031 } 1032 1033 /* 1034 * move to the next page, which is where the real stack starts. 1035 */ 1036 ks += PAGE_SIZE; 1037 td->td_kstack = ks; 1038 ptek++; 1039#else 1040 /* get a kernel virtual address for the kstack for this thread */ 1041 ks = kmem_alloc_nofault(kernel_map, KSTACK_PAGES * PAGE_SIZE); 1042 if (ks == 0) 1043 panic("pmap_new_thread: kstack allocation failed"); 1044 td->td_kstack = ks; 1045 ptek = vtopte(ks); 1046#endif 1047 /* 1048 * For the length of the stack, link in a real page of ram for each 1049 * page of stack. 1050 */ 1051 for (i = 0; i < KSTACK_PAGES; i++) { 1052 /* 1053 * Get a kernel stack page 1054 */ 1055 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1056 1057 /* 1058 * Wire the page 1059 */ 1060 m->wire_count++; 1061 cnt.v_wire_count++; 1062 1063 /* 1064 * Enter the page into the kernel address space. 1065 */ 1066 oldpte = ptek[i]; 1067 ptek[i] = VM_PAGE_TO_PHYS(m) | PG_RW | PG_V | pgeflag; 1068 if (oldpte) { 1069#ifdef I386_CPU 1070 updateneeded = 1; 1071#else 1072 invlpg(ks + (i * PAGE_SIZE)); 1073#endif 1074 } 1075 1076 vm_page_wakeup(m); 1077 vm_page_flag_clear(m, PG_ZERO); 1078 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 1079 m->valid = VM_PAGE_BITS_ALL; 1080 } 1081#ifdef I386_CPU 1082 if (updateneeded) 1083 invltlb(); 1084#endif 1085} 1086 1087/* 1088 * Dispose the kernel stack for a thread that has exited. 1089 * This routine directly impacts the exit perf of a process and thread. 1090 */ 1091void 1092pmap_dispose_thread(td) 1093 struct thread *td; 1094{ 1095 int i; 1096 vm_object_t ksobj; 1097 vm_offset_t ks; 1098 vm_page_t m; 1099 pt_entry_t *ptek, oldpte; 1100 1101 ksobj = td->td_kstack_obj; 1102 ks = td->td_kstack; 1103 ptek = vtopte(ks); 1104#ifdef KSTACK_GUARD 1105 ks -= PAGE_SIZE; 1106 for (i = 1; i < (KSTACK_PAGES + 1); i++) { 1107#else 1108 for (i = 0; i < KSTACK_PAGES; i++) { 1109#endif 1110 m = vm_page_lookup(ksobj, i); 1111 if (m == NULL) 1112 panic("pmap_dispose_thread: kstack already missing?"); 1113 vm_page_busy(m); 1114 oldpte = *(ptek + i); 1115 *(ptek + i) = 0; 1116#ifndef I386_CPU 1117 invlpg(ks + i * PAGE_SIZE); 1118#endif 1119 vm_page_unwire(m, 0); 1120 vm_page_free(m); 1121 } 1122#ifdef I386_CPU 1123 invltlb(); 1124#endif 1125 /* 1126 * Free the space that this stack was mapped to in the kernel 1127 * address map. 1128 */ 1129#ifdef KSTACK_GUARD 1130 kmem_free(kernel_map, ks, (KSTACK_PAGES + 1) * PAGE_SIZE); 1131#else 1132 kmem_free(kernel_map, ks, KSTACK_PAGES * PAGE_SIZE); 1133#endif 1134 vm_object_deallocate(ksobj); 1135 td->td_kstack_obj = NULL; /* play it safe */ 1136} 1137 1138/* 1139 * Allow the Kernel stack for a thread to be prejudicially paged out. 1140 */ 1141void 1142pmap_swapout_thread(td) 1143 struct thread *td; 1144{ 1145 int i; 1146 vm_object_t ksobj; 1147 vm_offset_t ks; 1148 vm_page_t m; 1149 1150 ksobj = td->td_kstack_obj; 1151 ks = td->td_kstack; 1152 for (i = 0; i < KSTACK_PAGES; i++) { 1153 m = vm_page_lookup(ksobj, i); 1154 if (m == NULL) 1155 panic("pmap_swapout_thread: kstack already missing?"); 1156 vm_page_dirty(m); 1157 vm_page_unwire(m, 0); 1158 pmap_kremove(ks + i * PAGE_SIZE); 1159 } 1160} 1161 1162/* 1163 * Bring the kernel stack for a specified thread back in. 1164 */ 1165void 1166pmap_swapin_thread(td) 1167 struct thread *td; 1168{ 1169 int i, rv; 1170 vm_object_t ksobj; 1171 vm_offset_t ks; 1172 vm_page_t m; 1173 1174 ksobj = td->td_kstack_obj; 1175 ks = td->td_kstack; 1176 for (i = 0; i < KSTACK_PAGES; i++) { 1177 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1178 pmap_kenter(ks + i * PAGE_SIZE, VM_PAGE_TO_PHYS(m)); 1179 if (m->valid != VM_PAGE_BITS_ALL) { 1180 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1181 if (rv != VM_PAGER_OK) 1182 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1183 m = vm_page_lookup(ksobj, i); 1184 m->valid = VM_PAGE_BITS_ALL; 1185 } 1186 vm_page_wire(m); 1187 vm_page_wakeup(m); 1188 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 1189 } 1190} 1191 1192/*************************************************** 1193 * Page table page management routines..... 1194 ***************************************************/ 1195 1196/* 1197 * This routine unholds page table pages, and if the hold count 1198 * drops to zero, then it decrements the wire count. 1199 */ 1200static int 1201_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1202{ 1203 1204 while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) 1205 ; 1206 1207 if (m->hold_count == 0) { 1208 vm_offset_t pteva; 1209 /* 1210 * unmap the page table page 1211 */ 1212 pmap->pm_pdir[m->pindex] = 0; 1213 --pmap->pm_stats.resident_count; 1214 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1215 (PTDpde & PG_FRAME)) { 1216 /* 1217 * Do a invltlb to make the invalidated mapping 1218 * take effect immediately. 1219 */ 1220 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); 1221 pmap_invalidate_page(pmap, pteva); 1222 } 1223 1224 if (pmap->pm_ptphint == m) 1225 pmap->pm_ptphint = NULL; 1226 1227 /* 1228 * If the page is finally unwired, simply free it. 1229 */ 1230 --m->wire_count; 1231 if (m->wire_count == 0) { 1232 1233 vm_page_flash(m); 1234 vm_page_busy(m); 1235 vm_page_free_zero(m); 1236 --cnt.v_wire_count; 1237 } 1238 return 1; 1239 } 1240 return 0; 1241} 1242 1243static PMAP_INLINE int 1244pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1245{ 1246 vm_page_unhold(m); 1247 if (m->hold_count == 0) 1248 return _pmap_unwire_pte_hold(pmap, m); 1249 else 1250 return 0; 1251} 1252 1253/* 1254 * After removing a page table entry, this routine is used to 1255 * conditionally free the page, and manage the hold/wire counts. 1256 */ 1257static int 1258pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1259{ 1260 unsigned ptepindex; 1261 if (va >= VM_MAXUSER_ADDRESS) 1262 return 0; 1263 1264 if (mpte == NULL) { 1265 ptepindex = (va >> PDRSHIFT); 1266 if (pmap->pm_ptphint && 1267 (pmap->pm_ptphint->pindex == ptepindex)) { 1268 mpte = pmap->pm_ptphint; 1269 } else { 1270 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1271 pmap->pm_ptphint = mpte; 1272 } 1273 } 1274 1275 return pmap_unwire_pte_hold(pmap, mpte); 1276} 1277 1278void 1279pmap_pinit0(pmap) 1280 struct pmap *pmap; 1281{ 1282 pmap->pm_pdir = 1283 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1284 pmap_kenter((vm_offset_t) pmap->pm_pdir, (vm_offset_t) IdlePTD); 1285 pmap->pm_ptphint = NULL; 1286 pmap->pm_active = 0; 1287 TAILQ_INIT(&pmap->pm_pvlist); 1288 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1289 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1290} 1291 1292/* 1293 * Initialize a preallocated and zeroed pmap structure, 1294 * such as one in a vmspace structure. 1295 */ 1296void 1297pmap_pinit(pmap) 1298 register struct pmap *pmap; 1299{ 1300 vm_page_t ptdpg; 1301 1302 /* 1303 * No need to allocate page table space yet but we do need a valid 1304 * page directory table. 1305 */ 1306 if (pmap->pm_pdir == NULL) 1307 pmap->pm_pdir = 1308 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1309 1310 /* 1311 * allocate object for the ptes 1312 */ 1313 if (pmap->pm_pteobj == NULL) 1314 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1315 1316 /* 1317 * allocate the page directory page 1318 */ 1319 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1320 VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1321 1322 ptdpg->wire_count = 1; 1323 ++cnt.v_wire_count; 1324 1325 1326 vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/ 1327 ptdpg->valid = VM_PAGE_BITS_ALL; 1328 1329 pmap_kenter((vm_offset_t) pmap->pm_pdir, VM_PAGE_TO_PHYS(ptdpg)); 1330 if ((ptdpg->flags & PG_ZERO) == 0) 1331 bzero(pmap->pm_pdir, PAGE_SIZE); 1332 1333 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1334 /* Wire in kernel global address entries. */ 1335 /* XXX copies current process, does not fill in MPPTDI */ 1336 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1337#ifdef SMP 1338 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1339#endif 1340 1341 /* install self-referential address mapping entry */ 1342 pmap->pm_pdir[PTDPTDI] = 1343 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1344 1345 pmap->pm_active = 0; 1346 pmap->pm_ptphint = NULL; 1347 TAILQ_INIT(&pmap->pm_pvlist); 1348 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1349} 1350 1351/* 1352 * Wire in kernel global address entries. To avoid a race condition 1353 * between pmap initialization and pmap_growkernel, this procedure 1354 * should be called after the vmspace is attached to the process 1355 * but before this pmap is activated. 1356 */ 1357void 1358pmap_pinit2(pmap) 1359 struct pmap *pmap; 1360{ 1361 /* XXX: Remove this stub when no longer called */ 1362} 1363 1364static int 1365pmap_release_free_page(pmap_t pmap, vm_page_t p) 1366{ 1367 pd_entry_t *pde = pmap->pm_pdir; 1368 /* 1369 * This code optimizes the case of freeing non-busy 1370 * page-table pages. Those pages are zero now, and 1371 * might as well be placed directly into the zero queue. 1372 */ 1373 if (vm_page_sleep_busy(p, FALSE, "pmaprl")) 1374 return 0; 1375 1376 vm_page_busy(p); 1377 1378 /* 1379 * Remove the page table page from the processes address space. 1380 */ 1381 pde[p->pindex] = 0; 1382 pmap->pm_stats.resident_count--; 1383 1384 if (p->hold_count) { 1385 panic("pmap_release: freeing held page table page"); 1386 } 1387 /* 1388 * Page directory pages need to have the kernel 1389 * stuff cleared, so they can go into the zero queue also. 1390 */ 1391 if (p->pindex == PTDPTDI) { 1392 bzero(pde + KPTDI, nkpt * PTESIZE); 1393#ifdef SMP 1394 pde[MPPTDI] = 0; 1395#endif 1396 pde[APTDPTDI] = 0; 1397 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1398 } 1399 1400 if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex)) 1401 pmap->pm_ptphint = NULL; 1402 1403 p->wire_count--; 1404 cnt.v_wire_count--; 1405 vm_page_free_zero(p); 1406 return 1; 1407} 1408 1409/* 1410 * this routine is called if the page table page is not 1411 * mapped correctly. 1412 */ 1413static vm_page_t 1414_pmap_allocpte(pmap, ptepindex) 1415 pmap_t pmap; 1416 unsigned ptepindex; 1417{ 1418 vm_offset_t pteva, ptepa; /* XXXPA */ 1419 vm_page_t m; 1420 1421 /* 1422 * Find or fabricate a new pagetable page 1423 */ 1424 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1425 VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1426 1427 KASSERT(m->queue == PQ_NONE, 1428 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1429 1430 if (m->wire_count == 0) 1431 cnt.v_wire_count++; 1432 m->wire_count++; 1433 1434 /* 1435 * Increment the hold count for the page table page 1436 * (denoting a new mapping.) 1437 */ 1438 m->hold_count++; 1439 1440 /* 1441 * Map the pagetable page into the process address space, if 1442 * it isn't already there. 1443 */ 1444 1445 pmap->pm_stats.resident_count++; 1446 1447 ptepa = VM_PAGE_TO_PHYS(m); 1448 pmap->pm_pdir[ptepindex] = 1449 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1450 1451 /* 1452 * Set the page table hint 1453 */ 1454 pmap->pm_ptphint = m; 1455 1456 /* 1457 * Try to use the new mapping, but if we cannot, then 1458 * do it with the routine that maps the page explicitly. 1459 */ 1460 if ((m->flags & PG_ZERO) == 0) { 1461 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1462 (PTDpde & PG_FRAME)) { 1463 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1464 bzero((caddr_t) pteva, PAGE_SIZE); 1465 } else { 1466 pmap_zero_page(m); 1467 } 1468 } 1469 1470 m->valid = VM_PAGE_BITS_ALL; 1471 vm_page_flag_clear(m, PG_ZERO); 1472 vm_page_flag_set(m, PG_MAPPED); 1473 vm_page_wakeup(m); 1474 1475 return m; 1476} 1477 1478static vm_page_t 1479pmap_allocpte(pmap_t pmap, vm_offset_t va) 1480{ 1481 unsigned ptepindex; 1482 pd_entry_t ptepa; 1483 vm_page_t m; 1484 1485 /* 1486 * Calculate pagetable page index 1487 */ 1488 ptepindex = va >> PDRSHIFT; 1489 1490 /* 1491 * Get the page directory entry 1492 */ 1493 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1494 1495 /* 1496 * This supports switching from a 4MB page to a 1497 * normal 4K page. 1498 */ 1499 if (ptepa & PG_PS) { 1500 pmap->pm_pdir[ptepindex] = 0; 1501 ptepa = 0; 1502 invltlb(); 1503 } 1504 1505 /* 1506 * If the page table page is mapped, we just increment the 1507 * hold count, and activate it. 1508 */ 1509 if (ptepa) { 1510 /* 1511 * In order to get the page table page, try the 1512 * hint first. 1513 */ 1514 if (pmap->pm_ptphint && 1515 (pmap->pm_ptphint->pindex == ptepindex)) { 1516 m = pmap->pm_ptphint; 1517 } else { 1518 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1519 pmap->pm_ptphint = m; 1520 } 1521 m->hold_count++; 1522 return m; 1523 } 1524 /* 1525 * Here if the pte page isn't mapped, or if it has been deallocated. 1526 */ 1527 return _pmap_allocpte(pmap, ptepindex); 1528} 1529 1530 1531/*************************************************** 1532* Pmap allocation/deallocation routines. 1533 ***************************************************/ 1534 1535/* 1536 * Release any resources held by the given physical map. 1537 * Called when a pmap initialized by pmap_pinit is being released. 1538 * Should only be called if the map contains no valid mappings. 1539 */ 1540void 1541pmap_release(pmap_t pmap) 1542{ 1543 vm_page_t p,n,ptdpg; 1544 vm_object_t object = pmap->pm_pteobj; 1545 int curgeneration; 1546 1547#if defined(DIAGNOSTIC) 1548 if (object->ref_count != 1) 1549 panic("pmap_release: pteobj reference count != 1"); 1550#endif 1551 1552 ptdpg = NULL; 1553 LIST_REMOVE(pmap, pm_list); 1554retry: 1555 curgeneration = object->generation; 1556 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1557 n = TAILQ_NEXT(p, listq); 1558 if (p->pindex == PTDPTDI) { 1559 ptdpg = p; 1560 continue; 1561 } 1562 while (1) { 1563 if (!pmap_release_free_page(pmap, p) && 1564 (object->generation != curgeneration)) 1565 goto retry; 1566 } 1567 } 1568 1569 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1570 goto retry; 1571} 1572 1573static int 1574kvm_size(SYSCTL_HANDLER_ARGS) 1575{ 1576 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1577 1578 return sysctl_handle_long(oidp, &ksize, 0, req); 1579} 1580SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1581 0, 0, kvm_size, "IU", "Size of KVM"); 1582 1583static int 1584kvm_free(SYSCTL_HANDLER_ARGS) 1585{ 1586 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1587 1588 return sysctl_handle_long(oidp, &kfree, 0, req); 1589} 1590SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1591 0, 0, kvm_free, "IU", "Amount of KVM free"); 1592 1593/* 1594 * grow the number of kernel page table entries, if needed 1595 */ 1596void 1597pmap_growkernel(vm_offset_t addr) 1598{ 1599 struct pmap *pmap; 1600 int s; 1601 vm_offset_t ptppaddr; 1602 vm_page_t nkpg; 1603 pd_entry_t newpdir; 1604 1605 s = splhigh(); 1606 if (kernel_vm_end == 0) { 1607 kernel_vm_end = KERNBASE; 1608 nkpt = 0; 1609 while (pdir_pde(PTD, kernel_vm_end)) { 1610 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1611 nkpt++; 1612 } 1613 } 1614 addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1615 while (kernel_vm_end < addr) { 1616 if (pdir_pde(PTD, kernel_vm_end)) { 1617 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1618 continue; 1619 } 1620 1621 /* 1622 * This index is bogus, but out of the way 1623 */ 1624 nkpg = vm_page_alloc(kptobj, nkpt, VM_ALLOC_SYSTEM); 1625 if (!nkpg) 1626 panic("pmap_growkernel: no memory to grow kernel"); 1627 1628 nkpt++; 1629 1630 vm_page_wire(nkpg); 1631 pmap_zero_page(nkpg); 1632 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1633 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1634 pdir_pde(PTD, kernel_vm_end) = newpdir; 1635 1636 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1637 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1638 } 1639 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1640 } 1641 splx(s); 1642} 1643 1644 1645/*************************************************** 1646 * page management routines. 1647 ***************************************************/ 1648 1649/* 1650 * free the pv_entry back to the free list 1651 */ 1652static PMAP_INLINE void 1653free_pv_entry(pv_entry_t pv) 1654{ 1655 pv_entry_count--; 1656 uma_zfree(pvzone, pv); 1657} 1658 1659/* 1660 * get a new pv_entry, allocating a block from the system 1661 * when needed. 1662 * the memory allocation is performed bypassing the malloc code 1663 * because of the possibility of allocations at interrupt time. 1664 */ 1665static pv_entry_t 1666get_pv_entry(void) 1667{ 1668 pv_entry_count++; 1669 if (pv_entry_high_water && 1670 (pv_entry_count > pv_entry_high_water) && 1671 (pmap_pagedaemon_waken == 0)) { 1672 pmap_pagedaemon_waken = 1; 1673 wakeup (&vm_pages_needed); 1674 } 1675 return uma_zalloc(pvzone, M_NOWAIT); 1676} 1677 1678/* 1679 * This routine is very drastic, but can save the system 1680 * in a pinch. 1681 */ 1682void 1683pmap_collect() 1684{ 1685 int i; 1686 vm_page_t m; 1687 static int warningdone = 0; 1688 1689 if (pmap_pagedaemon_waken == 0) 1690 return; 1691 1692 if (warningdone < 5) { 1693 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1694 warningdone++; 1695 } 1696 1697 for(i = 0; i < vm_page_array_size; i++) { 1698 m = &vm_page_array[i]; 1699 if (m->wire_count || m->hold_count || m->busy || 1700 (m->flags & (PG_BUSY | PG_UNMANAGED))) 1701 continue; 1702 pmap_remove_all(m); 1703 } 1704 pmap_pagedaemon_waken = 0; 1705} 1706 1707 1708/* 1709 * If it is the first entry on the list, it is actually 1710 * in the header and we must copy the following entry up 1711 * to the header. Otherwise we must search the list for 1712 * the entry. In either case we free the now unused entry. 1713 */ 1714 1715static int 1716pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1717{ 1718 pv_entry_t pv; 1719 int rtval; 1720 int s; 1721 1722 s = splvm(); 1723 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1724 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1725 if (pmap == pv->pv_pmap && va == pv->pv_va) 1726 break; 1727 } 1728 } else { 1729 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1730 if (va == pv->pv_va) 1731 break; 1732 } 1733 } 1734 1735 rtval = 0; 1736 if (pv) { 1737 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1738 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1739 m->md.pv_list_count--; 1740 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1741 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1742 1743 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1744 free_pv_entry(pv); 1745 } 1746 1747 splx(s); 1748 return rtval; 1749} 1750 1751/* 1752 * Create a pv entry for page at pa for 1753 * (pmap, va). 1754 */ 1755static void 1756pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1757{ 1758 1759 int s; 1760 pv_entry_t pv; 1761 1762 s = splvm(); 1763 pv = get_pv_entry(); 1764 pv->pv_va = va; 1765 pv->pv_pmap = pmap; 1766 pv->pv_ptem = mpte; 1767 1768 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1769 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1770 m->md.pv_list_count++; 1771 1772 splx(s); 1773} 1774 1775/* 1776 * pmap_remove_pte: do the things to unmap a page in a process 1777 */ 1778static int 1779pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1780{ 1781 pt_entry_t oldpte; 1782 vm_page_t m; 1783 1784 oldpte = atomic_readandclear_int(ptq); 1785 if (oldpte & PG_W) 1786 pmap->pm_stats.wired_count -= 1; 1787 /* 1788 * Machines that don't support invlpg, also don't support 1789 * PG_G. 1790 */ 1791 if (oldpte & PG_G) 1792 invlpg(va); 1793 pmap->pm_stats.resident_count -= 1; 1794 if (oldpte & PG_MANAGED) { 1795 m = PHYS_TO_VM_PAGE(oldpte); 1796 if (oldpte & PG_M) { 1797#if defined(PMAP_DIAGNOSTIC) 1798 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1799 printf( 1800 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1801 va, oldpte); 1802 } 1803#endif 1804 if (pmap_track_modified(va)) 1805 vm_page_dirty(m); 1806 } 1807 if (oldpte & PG_A) 1808 vm_page_flag_set(m, PG_REFERENCED); 1809 return pmap_remove_entry(pmap, m, va); 1810 } else { 1811 return pmap_unuse_pt(pmap, va, NULL); 1812 } 1813 1814 return 0; 1815} 1816 1817/* 1818 * Remove a single page from a process address space 1819 */ 1820static void 1821pmap_remove_page(pmap_t pmap, vm_offset_t va) 1822{ 1823 register pt_entry_t *ptq; 1824 1825 /* 1826 * if there is no pte for this address, just skip it!!! 1827 */ 1828 if (*pmap_pde(pmap, va) == 0) { 1829 return; 1830 } 1831 1832 /* 1833 * get a local va for mappings for this pmap. 1834 */ 1835 ptq = get_ptbase(pmap) + i386_btop(va); 1836 if (*ptq) { 1837 (void) pmap_remove_pte(pmap, ptq, va); 1838 pmap_invalidate_page(pmap, va); 1839 } 1840 return; 1841} 1842 1843/* 1844 * Remove the given range of addresses from the specified map. 1845 * 1846 * It is assumed that the start and end are properly 1847 * rounded to the page size. 1848 */ 1849void 1850pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1851{ 1852 register pt_entry_t *ptbase; 1853 vm_offset_t pdnxt; 1854 pd_entry_t ptpaddr; 1855 vm_offset_t sindex, eindex; 1856 int anyvalid; 1857 1858 if (pmap == NULL) 1859 return; 1860 1861 if (pmap->pm_stats.resident_count == 0) 1862 return; 1863 1864 /* 1865 * special handling of removing one page. a very 1866 * common operation and easy to short circuit some 1867 * code. 1868 */ 1869 if ((sva + PAGE_SIZE == eva) && 1870 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1871 pmap_remove_page(pmap, sva); 1872 return; 1873 } 1874 1875 anyvalid = 0; 1876 1877 /* 1878 * Get a local virtual address for the mappings that are being 1879 * worked with. 1880 */ 1881 ptbase = get_ptbase(pmap); 1882 1883 sindex = i386_btop(sva); 1884 eindex = i386_btop(eva); 1885 1886 for (; sindex < eindex; sindex = pdnxt) { 1887 unsigned pdirindex; 1888 1889 /* 1890 * Calculate index for next page table. 1891 */ 1892 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1893 if (pmap->pm_stats.resident_count == 0) 1894 break; 1895 1896 pdirindex = sindex / NPDEPG; 1897 ptpaddr = pmap->pm_pdir[pdirindex]; 1898 if ((ptpaddr & PG_PS) != 0) { 1899 pmap->pm_pdir[pdirindex] = 0; 1900 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1901 anyvalid++; 1902 continue; 1903 } 1904 1905 /* 1906 * Weed out invalid mappings. Note: we assume that the page 1907 * directory table is always allocated, and in kernel virtual. 1908 */ 1909 if (ptpaddr == 0) 1910 continue; 1911 1912 /* 1913 * Limit our scan to either the end of the va represented 1914 * by the current page table page, or to the end of the 1915 * range being removed. 1916 */ 1917 if (pdnxt > eindex) { 1918 pdnxt = eindex; 1919 } 1920 1921 for (; sindex != pdnxt; sindex++) { 1922 vm_offset_t va; 1923 if (ptbase[sindex] == 0) { 1924 continue; 1925 } 1926 va = i386_ptob(sindex); 1927 1928 anyvalid++; 1929 if (pmap_remove_pte(pmap, 1930 ptbase + sindex, va)) 1931 break; 1932 } 1933 } 1934 1935 if (anyvalid) 1936 pmap_invalidate_all(pmap); 1937} 1938 1939/* 1940 * Routine: pmap_remove_all 1941 * Function: 1942 * Removes this physical page from 1943 * all physical maps in which it resides. 1944 * Reflects back modify bits to the pager. 1945 * 1946 * Notes: 1947 * Original versions of this routine were very 1948 * inefficient because they iteratively called 1949 * pmap_remove (slow...) 1950 */ 1951 1952static void 1953pmap_remove_all(vm_page_t m) 1954{ 1955 register pv_entry_t pv; 1956 pt_entry_t *pte, tpte; 1957 int s; 1958 1959#if defined(PMAP_DIAGNOSTIC) 1960 /* 1961 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1962 * pages! 1963 */ 1964 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1965 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1966 } 1967#endif 1968 1969 s = splvm(); 1970 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1971 pv->pv_pmap->pm_stats.resident_count--; 1972 1973 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1974 1975 tpte = atomic_readandclear_int(pte); 1976 if (tpte & PG_W) 1977 pv->pv_pmap->pm_stats.wired_count--; 1978 1979 if (tpte & PG_A) 1980 vm_page_flag_set(m, PG_REFERENCED); 1981 1982 /* 1983 * Update the vm_page_t clean and reference bits. 1984 */ 1985 if (tpte & PG_M) { 1986#if defined(PMAP_DIAGNOSTIC) 1987 if (pmap_nw_modified((pt_entry_t) tpte)) { 1988 printf( 1989 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1990 pv->pv_va, tpte); 1991 } 1992#endif 1993 if (pmap_track_modified(pv->pv_va)) 1994 vm_page_dirty(m); 1995 } 1996 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1997 1998 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1999 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 2000 m->md.pv_list_count--; 2001 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 2002 free_pv_entry(pv); 2003 } 2004 2005 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 2006 2007 splx(s); 2008} 2009 2010/* 2011 * Set the physical protection on the 2012 * specified range of this map as requested. 2013 */ 2014void 2015pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 2016{ 2017 register pt_entry_t *ptbase; 2018 vm_offset_t pdnxt; 2019 pd_entry_t ptpaddr; 2020 vm_offset_t sindex, eindex; 2021 int anychanged; 2022 2023 if (pmap == NULL) 2024 return; 2025 2026 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 2027 pmap_remove(pmap, sva, eva); 2028 return; 2029 } 2030 2031 if (prot & VM_PROT_WRITE) 2032 return; 2033 2034 anychanged = 0; 2035 2036 ptbase = get_ptbase(pmap); 2037 2038 sindex = i386_btop(sva); 2039 eindex = i386_btop(eva); 2040 2041 for (; sindex < eindex; sindex = pdnxt) { 2042 2043 unsigned pdirindex; 2044 2045 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 2046 2047 pdirindex = sindex / NPDEPG; 2048 ptpaddr = pmap->pm_pdir[pdirindex]; 2049 if ((ptpaddr & PG_PS) != 0) { 2050 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 2051 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 2052 anychanged++; 2053 continue; 2054 } 2055 2056 /* 2057 * Weed out invalid mappings. Note: we assume that the page 2058 * directory table is always allocated, and in kernel virtual. 2059 */ 2060 if (ptpaddr == 0) 2061 continue; 2062 2063 if (pdnxt > eindex) { 2064 pdnxt = eindex; 2065 } 2066 2067 for (; sindex != pdnxt; sindex++) { 2068 2069 pt_entry_t pbits; 2070 vm_page_t m; 2071 2072 pbits = ptbase[sindex]; 2073 2074 if (pbits & PG_MANAGED) { 2075 m = NULL; 2076 if (pbits & PG_A) { 2077 m = PHYS_TO_VM_PAGE(pbits); 2078 vm_page_flag_set(m, PG_REFERENCED); 2079 pbits &= ~PG_A; 2080 } 2081 if (pbits & PG_M) { 2082 if (pmap_track_modified(i386_ptob(sindex))) { 2083 if (m == NULL) 2084 m = PHYS_TO_VM_PAGE(pbits); 2085 vm_page_dirty(m); 2086 pbits &= ~PG_M; 2087 } 2088 } 2089 } 2090 2091 pbits &= ~PG_RW; 2092 2093 if (pbits != ptbase[sindex]) { 2094 ptbase[sindex] = pbits; 2095 anychanged = 1; 2096 } 2097 } 2098 } 2099 if (anychanged) 2100 pmap_invalidate_all(pmap); 2101} 2102 2103/* 2104 * Insert the given physical page (p) at 2105 * the specified virtual address (v) in the 2106 * target physical map with the protection requested. 2107 * 2108 * If specified, the page will be wired down, meaning 2109 * that the related pte can not be reclaimed. 2110 * 2111 * NB: This is the only routine which MAY NOT lazy-evaluate 2112 * or lose information. That is, this routine must actually 2113 * insert this page into the given map NOW. 2114 */ 2115void 2116pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2117 boolean_t wired) 2118{ 2119 vm_offset_t pa; 2120 register pt_entry_t *pte; 2121 vm_offset_t opa; 2122 pt_entry_t origpte, newpte; 2123 vm_page_t mpte; 2124 2125 if (pmap == NULL) 2126 return; 2127 2128 va &= PG_FRAME; 2129#ifdef PMAP_DIAGNOSTIC 2130 if (va > VM_MAX_KERNEL_ADDRESS) 2131 panic("pmap_enter: toobig"); 2132 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2133 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2134#endif 2135 2136 mpte = NULL; 2137 /* 2138 * In the case that a page table page is not 2139 * resident, we are creating it here. 2140 */ 2141 if (va < VM_MAXUSER_ADDRESS) { 2142 mpte = pmap_allocpte(pmap, va); 2143 } 2144#if 0 && defined(PMAP_DIAGNOSTIC) 2145 else { 2146 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2147 origpte = *pdeaddr; 2148 if ((origpte & PG_V) == 0) { 2149 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2150 pmap->pm_pdir[PTDPTDI], origpte, va); 2151 } 2152 } 2153#endif 2154 2155 pte = pmap_pte(pmap, va); 2156 2157 /* 2158 * Page Directory table entry not valid, we need a new PT page 2159 */ 2160 if (pte == NULL) { 2161 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2162 (void *)pmap->pm_pdir[PTDPTDI], va); 2163 } 2164 2165 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2166 origpte = *(vm_offset_t *)pte; 2167 opa = origpte & PG_FRAME; 2168 2169 if (origpte & PG_PS) 2170 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2171 2172 /* 2173 * Mapping has not changed, must be protection or wiring change. 2174 */ 2175 if (origpte && (opa == pa)) { 2176 /* 2177 * Wiring change, just update stats. We don't worry about 2178 * wiring PT pages as they remain resident as long as there 2179 * are valid mappings in them. Hence, if a user page is wired, 2180 * the PT page will be also. 2181 */ 2182 if (wired && ((origpte & PG_W) == 0)) 2183 pmap->pm_stats.wired_count++; 2184 else if (!wired && (origpte & PG_W)) 2185 pmap->pm_stats.wired_count--; 2186 2187#if defined(PMAP_DIAGNOSTIC) 2188 if (pmap_nw_modified((pt_entry_t) origpte)) { 2189 printf( 2190 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2191 va, origpte); 2192 } 2193#endif 2194 2195 /* 2196 * Remove extra pte reference 2197 */ 2198 if (mpte) 2199 mpte->hold_count--; 2200 2201 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2202 if ((origpte & PG_RW) == 0) { 2203 *pte |= PG_RW; 2204#ifdef SMP 2205 cpu_invlpg((void *)va); 2206 if (pmap->pm_active & PCPU_GET(other_cpus)) 2207 smp_invltlb(); 2208#else 2209 invltlb_1pg(va); 2210#endif 2211 } 2212 return; 2213 } 2214 2215 /* 2216 * We might be turning off write access to the page, 2217 * so we go ahead and sense modify status. 2218 */ 2219 if (origpte & PG_MANAGED) { 2220 if ((origpte & PG_M) && pmap_track_modified(va)) { 2221 vm_page_t om; 2222 om = PHYS_TO_VM_PAGE(opa); 2223 vm_page_dirty(om); 2224 } 2225 pa |= PG_MANAGED; 2226 } 2227 goto validate; 2228 } 2229 /* 2230 * Mapping has changed, invalidate old range and fall through to 2231 * handle validating new mapping. 2232 */ 2233 if (opa) { 2234 int err; 2235 err = pmap_remove_pte(pmap, pte, va); 2236 if (err) 2237 panic("pmap_enter: pte vanished, va: 0x%x", va); 2238 } 2239 2240 /* 2241 * Enter on the PV list if part of our managed memory. Note that we 2242 * raise IPL while manipulating pv_table since pmap_enter can be 2243 * called at interrupt time. 2244 */ 2245 if (pmap_initialized && 2246 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2247 pmap_insert_entry(pmap, va, mpte, m); 2248 pa |= PG_MANAGED; 2249 } 2250 2251 /* 2252 * Increment counters 2253 */ 2254 pmap->pm_stats.resident_count++; 2255 if (wired) 2256 pmap->pm_stats.wired_count++; 2257 2258validate: 2259 /* 2260 * Now validate mapping with desired protection/wiring. 2261 */ 2262 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2263 2264 if (wired) 2265 newpte |= PG_W; 2266 if (va < VM_MAXUSER_ADDRESS) 2267 newpte |= PG_U; 2268 if (pmap == kernel_pmap) 2269 newpte |= pgeflag; 2270 2271 /* 2272 * if the mapping or permission bits are different, we need 2273 * to update the pte. 2274 */ 2275 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2276 *pte = newpte | PG_A; 2277 /*if (origpte)*/ { 2278#ifdef SMP 2279 cpu_invlpg((void *)va); 2280 if (pmap->pm_active & PCPU_GET(other_cpus)) 2281 smp_invltlb(); 2282#else 2283 invltlb_1pg(va); 2284#endif 2285 } 2286 } 2287} 2288 2289/* 2290 * this code makes some *MAJOR* assumptions: 2291 * 1. Current pmap & pmap exists. 2292 * 2. Not wired. 2293 * 3. Read access. 2294 * 4. No page table pages. 2295 * 5. Tlbflush is deferred to calling procedure. 2296 * 6. Page IS managed. 2297 * but is *MUCH* faster than pmap_enter... 2298 */ 2299 2300static vm_page_t 2301pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2302{ 2303 pt_entry_t *pte; 2304 vm_offset_t pa; 2305 2306 /* 2307 * In the case that a page table page is not 2308 * resident, we are creating it here. 2309 */ 2310 if (va < VM_MAXUSER_ADDRESS) { 2311 unsigned ptepindex; 2312 pd_entry_t ptepa; 2313 2314 /* 2315 * Calculate pagetable page index 2316 */ 2317 ptepindex = va >> PDRSHIFT; 2318 if (mpte && (mpte->pindex == ptepindex)) { 2319 mpte->hold_count++; 2320 } else { 2321retry: 2322 /* 2323 * Get the page directory entry 2324 */ 2325 ptepa = pmap->pm_pdir[ptepindex]; 2326 2327 /* 2328 * If the page table page is mapped, we just increment 2329 * the hold count, and activate it. 2330 */ 2331 if (ptepa) { 2332 if (ptepa & PG_PS) 2333 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2334 if (pmap->pm_ptphint && 2335 (pmap->pm_ptphint->pindex == ptepindex)) { 2336 mpte = pmap->pm_ptphint; 2337 } else { 2338 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2339 pmap->pm_ptphint = mpte; 2340 } 2341 if (mpte == NULL) 2342 goto retry; 2343 mpte->hold_count++; 2344 } else { 2345 mpte = _pmap_allocpte(pmap, ptepindex); 2346 } 2347 } 2348 } else { 2349 mpte = NULL; 2350 } 2351 2352 /* 2353 * This call to vtopte makes the assumption that we are 2354 * entering the page into the current pmap. In order to support 2355 * quick entry into any pmap, one would likely use pmap_pte_quick. 2356 * But that isn't as quick as vtopte. 2357 */ 2358 pte = vtopte(va); 2359 if (*pte) { 2360 if (mpte) 2361 pmap_unwire_pte_hold(pmap, mpte); 2362 return 0; 2363 } 2364 2365 /* 2366 * Enter on the PV list if part of our managed memory. Note that we 2367 * raise IPL while manipulating pv_table since pmap_enter can be 2368 * called at interrupt time. 2369 */ 2370 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2371 pmap_insert_entry(pmap, va, mpte, m); 2372 2373 /* 2374 * Increment counters 2375 */ 2376 pmap->pm_stats.resident_count++; 2377 2378 pa = VM_PAGE_TO_PHYS(m); 2379 2380 /* 2381 * Now validate mapping with RO protection 2382 */ 2383 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2384 *pte = pa | PG_V | PG_U; 2385 else 2386 *pte = pa | PG_V | PG_U | PG_MANAGED; 2387 2388 return mpte; 2389} 2390 2391/* 2392 * Make a temporary mapping for a physical address. This is only intended 2393 * to be used for panic dumps. 2394 */ 2395void * 2396pmap_kenter_temporary(vm_offset_t pa, int i) 2397{ 2398 pmap_kenter((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa); 2399 return ((void *)crashdumpmap); 2400} 2401 2402#define MAX_INIT_PT (96) 2403/* 2404 * pmap_object_init_pt preloads the ptes for a given object 2405 * into the specified pmap. This eliminates the blast of soft 2406 * faults on process startup and immediately after an mmap. 2407 */ 2408void 2409pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2410 vm_object_t object, vm_pindex_t pindex, 2411 vm_size_t size, int limit) 2412{ 2413 vm_offset_t tmpidx; 2414 int psize; 2415 vm_page_t p, mpte; 2416 int objpgs; 2417 2418 if (pmap == NULL || object == NULL) 2419 return; 2420 2421 /* 2422 * This code maps large physical mmap regions into the 2423 * processor address space. Note that some shortcuts 2424 * are taken, but the code works. 2425 */ 2426 if (pseflag && (object->type == OBJT_DEVICE) && 2427 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2428 int i; 2429 vm_page_t m[1]; 2430 unsigned int ptepindex; 2431 int npdes; 2432 pd_entry_t ptepa; 2433 2434 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2435 return; 2436 2437retry: 2438 p = vm_page_lookup(object, pindex); 2439 if (p && vm_page_sleep_busy(p, FALSE, "init4p")) 2440 goto retry; 2441 2442 if (p == NULL) { 2443 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2444 if (p == NULL) 2445 return; 2446 m[0] = p; 2447 2448 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2449 vm_page_free(p); 2450 return; 2451 } 2452 2453 p = vm_page_lookup(object, pindex); 2454 vm_page_wakeup(p); 2455 } 2456 2457 ptepa = VM_PAGE_TO_PHYS(p); 2458 if (ptepa & (NBPDR - 1)) { 2459 return; 2460 } 2461 2462 p->valid = VM_PAGE_BITS_ALL; 2463 2464 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2465 npdes = size >> PDRSHIFT; 2466 for(i = 0; i < npdes; i++) { 2467 pmap->pm_pdir[ptepindex] = 2468 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2469 ptepa += NBPDR; 2470 ptepindex += 1; 2471 } 2472 vm_page_flag_set(p, PG_MAPPED); 2473 invltlb(); 2474 return; 2475 } 2476 2477 psize = i386_btop(size); 2478 2479 if ((object->type != OBJT_VNODE) || 2480 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2481 (object->resident_page_count > MAX_INIT_PT))) { 2482 return; 2483 } 2484 2485 if (psize + pindex > object->size) { 2486 if (object->size < pindex) 2487 return; 2488 psize = object->size - pindex; 2489 } 2490 2491 mpte = NULL; 2492 /* 2493 * if we are processing a major portion of the object, then scan the 2494 * entire thing. 2495 */ 2496 if (psize > (object->resident_page_count >> 2)) { 2497 objpgs = psize; 2498 2499 for (p = TAILQ_FIRST(&object->memq); 2500 ((objpgs > 0) && (p != NULL)); 2501 p = TAILQ_NEXT(p, listq)) { 2502 2503 if (p->pindex < pindex || p->pindex - pindex >= psize) { 2504 continue; 2505 } 2506 tmpidx = p->pindex - pindex; 2507 /* 2508 * don't allow an madvise to blow away our really 2509 * free pages allocating pv entries. 2510 */ 2511 if ((limit & MAP_PREFAULT_MADVISE) && 2512 cnt.v_free_count < cnt.v_free_reserved) { 2513 break; 2514 } 2515 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2516 (p->busy == 0) && 2517 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2518 if ((p->queue - p->pc) == PQ_CACHE) 2519 vm_page_deactivate(p); 2520 vm_page_busy(p); 2521 mpte = pmap_enter_quick(pmap, 2522 addr + i386_ptob(tmpidx), p, mpte); 2523 vm_page_flag_set(p, PG_MAPPED); 2524 vm_page_wakeup(p); 2525 } 2526 objpgs -= 1; 2527 } 2528 } else { 2529 /* 2530 * else lookup the pages one-by-one. 2531 */ 2532 for (tmpidx = 0; tmpidx < psize; tmpidx += 1) { 2533 /* 2534 * don't allow an madvise to blow away our really 2535 * free pages allocating pv entries. 2536 */ 2537 if ((limit & MAP_PREFAULT_MADVISE) && 2538 cnt.v_free_count < cnt.v_free_reserved) { 2539 break; 2540 } 2541 p = vm_page_lookup(object, tmpidx + pindex); 2542 if (p && 2543 ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2544 (p->busy == 0) && 2545 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2546 if ((p->queue - p->pc) == PQ_CACHE) 2547 vm_page_deactivate(p); 2548 vm_page_busy(p); 2549 mpte = pmap_enter_quick(pmap, 2550 addr + i386_ptob(tmpidx), p, mpte); 2551 vm_page_flag_set(p, PG_MAPPED); 2552 vm_page_wakeup(p); 2553 } 2554 } 2555 } 2556 return; 2557} 2558 2559/* 2560 * pmap_prefault provides a quick way of clustering 2561 * pagefaults into a processes address space. It is a "cousin" 2562 * of pmap_object_init_pt, except it runs at page fault time instead 2563 * of mmap time. 2564 */ 2565#define PFBAK 4 2566#define PFFOR 4 2567#define PAGEORDER_SIZE (PFBAK+PFFOR) 2568 2569static int pmap_prefault_pageorder[] = { 2570 -PAGE_SIZE, PAGE_SIZE, 2571 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2572 -3 * PAGE_SIZE, 3 * PAGE_SIZE 2573 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2574}; 2575 2576void 2577pmap_prefault(pmap, addra, entry) 2578 pmap_t pmap; 2579 vm_offset_t addra; 2580 vm_map_entry_t entry; 2581{ 2582 int i; 2583 vm_offset_t starta; 2584 vm_offset_t addr; 2585 vm_pindex_t pindex; 2586 vm_page_t m, mpte; 2587 vm_object_t object; 2588 2589 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2590 return; 2591 2592 object = entry->object.vm_object; 2593 2594 starta = addra - PFBAK * PAGE_SIZE; 2595 if (starta < entry->start) { 2596 starta = entry->start; 2597 } else if (starta > addra) { 2598 starta = 0; 2599 } 2600 2601 mpte = NULL; 2602 for (i = 0; i < PAGEORDER_SIZE; i++) { 2603 vm_object_t lobject; 2604 pt_entry_t *pte; 2605 2606 addr = addra + pmap_prefault_pageorder[i]; 2607 if (addr > addra + (PFFOR * PAGE_SIZE)) 2608 addr = 0; 2609 2610 if (addr < starta || addr >= entry->end) 2611 continue; 2612 2613 if ((*pmap_pde(pmap, addr)) == NULL) 2614 continue; 2615 2616 pte = vtopte(addr); 2617 if (*pte) 2618 continue; 2619 2620 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2621 lobject = object; 2622 for (m = vm_page_lookup(lobject, pindex); 2623 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2624 lobject = lobject->backing_object) { 2625 if (lobject->backing_object_offset & PAGE_MASK) 2626 break; 2627 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2628 m = vm_page_lookup(lobject->backing_object, pindex); 2629 } 2630 2631 /* 2632 * give-up when a page is not in memory 2633 */ 2634 if (m == NULL) 2635 break; 2636 2637 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2638 (m->busy == 0) && 2639 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2640 2641 if ((m->queue - m->pc) == PQ_CACHE) { 2642 vm_page_deactivate(m); 2643 } 2644 vm_page_busy(m); 2645 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2646 vm_page_flag_set(m, PG_MAPPED); 2647 vm_page_wakeup(m); 2648 } 2649 } 2650} 2651 2652/* 2653 * Routine: pmap_change_wiring 2654 * Function: Change the wiring attribute for a map/virtual-address 2655 * pair. 2656 * In/out conditions: 2657 * The mapping must already exist in the pmap. 2658 */ 2659void 2660pmap_change_wiring(pmap, va, wired) 2661 register pmap_t pmap; 2662 vm_offset_t va; 2663 boolean_t wired; 2664{ 2665 register pt_entry_t *pte; 2666 2667 if (pmap == NULL) 2668 return; 2669 2670 pte = pmap_pte(pmap, va); 2671 2672 if (wired && !pmap_pte_w(pte)) 2673 pmap->pm_stats.wired_count++; 2674 else if (!wired && pmap_pte_w(pte)) 2675 pmap->pm_stats.wired_count--; 2676 2677 /* 2678 * Wiring is not a hardware characteristic so there is no need to 2679 * invalidate TLB. 2680 */ 2681 pmap_pte_set_w(pte, wired); 2682} 2683 2684 2685 2686/* 2687 * Copy the range specified by src_addr/len 2688 * from the source map to the range dst_addr/len 2689 * in the destination map. 2690 * 2691 * This routine is only advisory and need not do anything. 2692 */ 2693 2694void 2695pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2696 vm_offset_t src_addr) 2697{ 2698 vm_offset_t addr; 2699 vm_offset_t end_addr = src_addr + len; 2700 vm_offset_t pdnxt; 2701 pd_entry_t src_frame, dst_frame; 2702 vm_page_t m; 2703 pd_entry_t saved_pde; 2704 2705 if (dst_addr != src_addr) 2706 return; 2707 2708 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2709 if (src_frame != (PTDpde & PG_FRAME)) 2710 return; 2711 2712 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2713 if (dst_frame != (APTDpde & PG_FRAME)) { 2714 APTDpde = dst_frame | PG_RW | PG_V; 2715#if defined(SMP) 2716 /* The page directory is not shared between CPUs */ 2717 cpu_invltlb(); 2718#else 2719 invltlb(); 2720#endif 2721 } 2722 saved_pde = APTDpde & (PG_FRAME | PG_RW | PG_V); 2723 for(addr = src_addr; addr < end_addr; addr = pdnxt) { 2724 pt_entry_t *src_pte, *dst_pte; 2725 vm_page_t dstmpte, srcmpte; 2726 pd_entry_t srcptepaddr; 2727 unsigned ptepindex; 2728 2729 if (addr >= UPT_MIN_ADDRESS) 2730 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2731 2732 /* 2733 * Don't let optional prefaulting of pages make us go 2734 * way below the low water mark of free pages or way 2735 * above high water mark of used pv entries. 2736 */ 2737 if (cnt.v_free_count < cnt.v_free_reserved || 2738 pv_entry_count > pv_entry_high_water) 2739 break; 2740 2741 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2742 ptepindex = addr >> PDRSHIFT; 2743 2744 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2745 if (srcptepaddr == 0) 2746 continue; 2747 2748 if (srcptepaddr & PG_PS) { 2749 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2750 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2751 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2752 } 2753 continue; 2754 } 2755 2756 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2757 if ((srcmpte == NULL) || 2758 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2759 continue; 2760 2761 if (pdnxt > end_addr) 2762 pdnxt = end_addr; 2763 2764 src_pte = vtopte(addr); 2765 dst_pte = avtopte(addr); 2766 while (addr < pdnxt) { 2767 pt_entry_t ptetemp; 2768 ptetemp = *src_pte; 2769 /* 2770 * we only virtual copy managed pages 2771 */ 2772 if ((ptetemp & PG_MANAGED) != 0) { 2773 /* 2774 * We have to check after allocpte for the 2775 * pte still being around... allocpte can 2776 * block. 2777 */ 2778 dstmpte = pmap_allocpte(dst_pmap, addr); 2779 if ((APTDpde & PG_FRAME) != 2780 (saved_pde & PG_FRAME)) { 2781 APTDpde = saved_pde; 2782printf ("IT HAPPENNED!"); 2783#if defined(SMP) 2784 cpu_invltlb(); 2785#else 2786 invltlb(); 2787#endif 2788 } 2789 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2790 /* 2791 * Clear the modified and 2792 * accessed (referenced) bits 2793 * during the copy. 2794 */ 2795 m = PHYS_TO_VM_PAGE(ptetemp); 2796 *dst_pte = ptetemp & ~(PG_M | PG_A); 2797 dst_pmap->pm_stats.resident_count++; 2798 pmap_insert_entry(dst_pmap, addr, 2799 dstmpte, m); 2800 } else { 2801 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2802 } 2803 if (dstmpte->hold_count >= srcmpte->hold_count) 2804 break; 2805 } 2806 addr += PAGE_SIZE; 2807 src_pte++; 2808 dst_pte++; 2809 } 2810 } 2811} 2812 2813/* 2814 * pmap_zero_page zeros the specified hardware page by mapping 2815 * the page into KVM and using bzero to clear its contents. 2816 */ 2817void 2818pmap_zero_page(vm_page_t m) 2819{ 2820 vm_offset_t phys = VM_PAGE_TO_PHYS(m); 2821 2822 if (*CMAP2) 2823 panic("pmap_zero_page: CMAP2 busy"); 2824 2825 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2826 invltlb_1pg((vm_offset_t)CADDR2); 2827 2828#if defined(I686_CPU) 2829 if (cpu_class == CPUCLASS_686) 2830 i686_pagezero(CADDR2); 2831 else 2832#endif 2833 bzero(CADDR2, PAGE_SIZE); 2834 *CMAP2 = 0; 2835} 2836 2837/* 2838 * pmap_zero_page_area zeros the specified hardware page by mapping 2839 * the page into KVM and using bzero to clear its contents. 2840 * 2841 * off and size may not cover an area beyond a single hardware page. 2842 */ 2843void 2844pmap_zero_page_area(vm_page_t m, int off, int size) 2845{ 2846 vm_offset_t phys = VM_PAGE_TO_PHYS(m); 2847 2848 if (*CMAP2) 2849 panic("pmap_zero_page: CMAP2 busy"); 2850 2851 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2852 invltlb_1pg((vm_offset_t)CADDR2); 2853 2854#if defined(I686_CPU) 2855 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2856 i686_pagezero(CADDR2); 2857 else 2858#endif 2859 bzero((char *)CADDR2 + off, size); 2860 *CMAP2 = 0; 2861} 2862 2863/* 2864 * pmap_copy_page copies the specified (machine independent) 2865 * page by mapping the page into virtual memory and using 2866 * bcopy to copy the page, one machine dependent page at a 2867 * time. 2868 */ 2869void 2870pmap_copy_page(vm_page_t src, vm_page_t dst) 2871{ 2872 2873 if (*CMAP1) 2874 panic("pmap_copy_page: CMAP1 busy"); 2875 if (*CMAP2) 2876 panic("pmap_copy_page: CMAP2 busy"); 2877 2878 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2879 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2880#ifdef I386_CPU 2881 invltlb(); 2882#else 2883 invlpg((u_int)CADDR1); 2884 invlpg((u_int)CADDR2); 2885#endif 2886 2887 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2888 2889 *CMAP1 = 0; 2890 *CMAP2 = 0; 2891} 2892 2893 2894/* 2895 * Routine: pmap_pageable 2896 * Function: 2897 * Make the specified pages (by pmap, offset) 2898 * pageable (or not) as requested. 2899 * 2900 * A page which is not pageable may not take 2901 * a fault; therefore, its page table entry 2902 * must remain valid for the duration. 2903 * 2904 * This routine is merely advisory; pmap_enter 2905 * will specify that these pages are to be wired 2906 * down (or not) as appropriate. 2907 */ 2908void 2909pmap_pageable(pmap, sva, eva, pageable) 2910 pmap_t pmap; 2911 vm_offset_t sva, eva; 2912 boolean_t pageable; 2913{ 2914} 2915 2916/* 2917 * Returns true if the pmap's pv is one of the first 2918 * 16 pvs linked to from this page. This count may 2919 * be changed upwards or downwards in the future; it 2920 * is only necessary that true be returned for a small 2921 * subset of pmaps for proper page aging. 2922 */ 2923boolean_t 2924pmap_page_exists_quick(pmap, m) 2925 pmap_t pmap; 2926 vm_page_t m; 2927{ 2928 pv_entry_t pv; 2929 int loops = 0; 2930 int s; 2931 2932 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2933 return FALSE; 2934 2935 s = splvm(); 2936 2937 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2938 if (pv->pv_pmap == pmap) { 2939 splx(s); 2940 return TRUE; 2941 } 2942 loops++; 2943 if (loops >= 16) 2944 break; 2945 } 2946 splx(s); 2947 return (FALSE); 2948} 2949 2950#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2951/* 2952 * Remove all pages from specified address space 2953 * this aids process exit speeds. Also, this code 2954 * is special cased for current process only, but 2955 * can have the more generic (and slightly slower) 2956 * mode enabled. This is much faster than pmap_remove 2957 * in the case of running down an entire address space. 2958 */ 2959void 2960pmap_remove_pages(pmap, sva, eva) 2961 pmap_t pmap; 2962 vm_offset_t sva, eva; 2963{ 2964 pt_entry_t *pte, tpte; 2965 vm_page_t m; 2966 pv_entry_t pv, npv; 2967 int s; 2968 2969#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2970 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2971 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2972 return; 2973 } 2974#endif 2975 2976 s = splvm(); 2977 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2978 2979 if (pv->pv_va >= eva || pv->pv_va < sva) { 2980 npv = TAILQ_NEXT(pv, pv_plist); 2981 continue; 2982 } 2983 2984#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2985 pte = vtopte(pv->pv_va); 2986#else 2987 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2988#endif 2989 tpte = *pte; 2990 2991 if (tpte == 0) { 2992 printf("TPTE at %p IS ZERO @ VA %08x\n", 2993 pte, pv->pv_va); 2994 panic("bad pte"); 2995 } 2996 2997/* 2998 * We cannot remove wired pages from a process' mapping at this time 2999 */ 3000 if (tpte & PG_W) { 3001 npv = TAILQ_NEXT(pv, pv_plist); 3002 continue; 3003 } 3004 3005 m = PHYS_TO_VM_PAGE(tpte); 3006 KASSERT(m->phys_addr == (tpte & PG_FRAME), 3007 ("vm_page_t %p phys_addr mismatch %08x %08x", 3008 m, m->phys_addr, tpte)); 3009 3010 KASSERT(m < &vm_page_array[vm_page_array_size], 3011 ("pmap_remove_pages: bad tpte %x", tpte)); 3012 3013 pv->pv_pmap->pm_stats.resident_count--; 3014 3015 *pte = 0; 3016 3017 /* 3018 * Update the vm_page_t clean and reference bits. 3019 */ 3020 if (tpte & PG_M) { 3021 vm_page_dirty(m); 3022 } 3023 3024 npv = TAILQ_NEXT(pv, pv_plist); 3025 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 3026 3027 m->md.pv_list_count--; 3028 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3029 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 3030 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 3031 } 3032 3033 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 3034 free_pv_entry(pv); 3035 } 3036 splx(s); 3037 pmap_invalidate_all(pmap); 3038} 3039 3040/* 3041 * pmap_testbit tests bits in pte's 3042 * note that the testbit/changebit routines are inline, 3043 * and a lot of things compile-time evaluate. 3044 */ 3045static boolean_t 3046pmap_testbit(m, bit) 3047 vm_page_t m; 3048 int bit; 3049{ 3050 pv_entry_t pv; 3051 pt_entry_t *pte; 3052 int s; 3053 3054 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3055 return FALSE; 3056 3057 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 3058 return FALSE; 3059 3060 s = splvm(); 3061 3062 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3063 /* 3064 * if the bit being tested is the modified bit, then 3065 * mark clean_map and ptes as never 3066 * modified. 3067 */ 3068 if (bit & (PG_A|PG_M)) { 3069 if (!pmap_track_modified(pv->pv_va)) 3070 continue; 3071 } 3072 3073#if defined(PMAP_DIAGNOSTIC) 3074 if (!pv->pv_pmap) { 3075 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3076 continue; 3077 } 3078#endif 3079 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3080 if (*pte & bit) { 3081 splx(s); 3082 return TRUE; 3083 } 3084 } 3085 splx(s); 3086 return (FALSE); 3087} 3088 3089/* 3090 * this routine is used to modify bits in ptes 3091 */ 3092static __inline void 3093pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3094{ 3095 register pv_entry_t pv; 3096 register pt_entry_t *pte; 3097 int s; 3098 3099 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3100 return; 3101 3102 s = splvm(); 3103 3104 /* 3105 * Loop over all current mappings setting/clearing as appropos If 3106 * setting RO do we need to clear the VAC? 3107 */ 3108 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3109 /* 3110 * don't write protect pager mappings 3111 */ 3112 if (!setem && (bit == PG_RW)) { 3113 if (!pmap_track_modified(pv->pv_va)) 3114 continue; 3115 } 3116 3117#if defined(PMAP_DIAGNOSTIC) 3118 if (!pv->pv_pmap) { 3119 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3120 continue; 3121 } 3122#endif 3123 3124 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3125 3126 if (setem) { 3127 *pte |= bit; 3128 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3129 } else { 3130 pt_entry_t pbits = *pte; 3131 if (pbits & bit) { 3132 if (bit == PG_RW) { 3133 if (pbits & PG_M) { 3134 vm_page_dirty(m); 3135 } 3136 *pte = pbits & ~(PG_M|PG_RW); 3137 } else { 3138 *pte = pbits & ~bit; 3139 } 3140 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3141 } 3142 } 3143 } 3144 splx(s); 3145} 3146 3147/* 3148 * pmap_page_protect: 3149 * 3150 * Lower the permission for all mappings to a given page. 3151 */ 3152void 3153pmap_page_protect(vm_page_t m, vm_prot_t prot) 3154{ 3155 if ((prot & VM_PROT_WRITE) == 0) { 3156 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3157 pmap_changebit(m, PG_RW, FALSE); 3158 } else { 3159 pmap_remove_all(m); 3160 } 3161 } 3162} 3163 3164vm_offset_t 3165pmap_phys_address(ppn) 3166 int ppn; 3167{ 3168 return (i386_ptob(ppn)); 3169} 3170 3171/* 3172 * pmap_ts_referenced: 3173 * 3174 * Return a count of reference bits for a page, clearing those bits. 3175 * It is not necessary for every reference bit to be cleared, but it 3176 * is necessary that 0 only be returned when there are truly no 3177 * reference bits set. 3178 * 3179 * XXX: The exact number of bits to check and clear is a matter that 3180 * should be tested and standardized at some point in the future for 3181 * optimal aging of shared pages. 3182 */ 3183int 3184pmap_ts_referenced(vm_page_t m) 3185{ 3186 register pv_entry_t pv, pvf, pvn; 3187 pt_entry_t *pte; 3188 int s; 3189 int rtval = 0; 3190 3191 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3192 return (rtval); 3193 3194 s = splvm(); 3195 3196 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3197 3198 pvf = pv; 3199 3200 do { 3201 pvn = TAILQ_NEXT(pv, pv_list); 3202 3203 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3204 3205 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3206 3207 if (!pmap_track_modified(pv->pv_va)) 3208 continue; 3209 3210 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3211 3212 if (pte && (*pte & PG_A)) { 3213 *pte &= ~PG_A; 3214 3215 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3216 3217 rtval++; 3218 if (rtval > 4) { 3219 break; 3220 } 3221 } 3222 } while ((pv = pvn) != NULL && pv != pvf); 3223 } 3224 splx(s); 3225 3226 return (rtval); 3227} 3228 3229/* 3230 * pmap_is_modified: 3231 * 3232 * Return whether or not the specified physical page was modified 3233 * in any physical maps. 3234 */ 3235boolean_t 3236pmap_is_modified(vm_page_t m) 3237{ 3238 return pmap_testbit(m, PG_M); 3239} 3240 3241/* 3242 * Clear the modify bits on the specified physical page. 3243 */ 3244void 3245pmap_clear_modify(vm_page_t m) 3246{ 3247 pmap_changebit(m, PG_M, FALSE); 3248} 3249 3250/* 3251 * pmap_clear_reference: 3252 * 3253 * Clear the reference bit on the specified physical page. 3254 */ 3255void 3256pmap_clear_reference(vm_page_t m) 3257{ 3258 pmap_changebit(m, PG_A, FALSE); 3259} 3260 3261/* 3262 * Miscellaneous support routines follow 3263 */ 3264 3265static void 3266i386_protection_init() 3267{ 3268 register int *kp, prot; 3269 3270 kp = protection_codes; 3271 for (prot = 0; prot < 8; prot++) { 3272 switch (prot) { 3273 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3274 /* 3275 * Read access is also 0. There isn't any execute bit, 3276 * so just make it readable. 3277 */ 3278 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3279 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3280 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3281 *kp++ = 0; 3282 break; 3283 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3284 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3285 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3286 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3287 *kp++ = PG_RW; 3288 break; 3289 } 3290 } 3291} 3292 3293/* 3294 * Map a set of physical memory pages into the kernel virtual 3295 * address space. Return a pointer to where it is mapped. This 3296 * routine is intended to be used for mapping device memory, 3297 * NOT real memory. 3298 */ 3299void * 3300pmap_mapdev(pa, size) 3301 vm_offset_t pa; 3302 vm_size_t size; 3303{ 3304 vm_offset_t va, tmpva, offset; 3305 pt_entry_t *pte; 3306 3307 offset = pa & PAGE_MASK; 3308 size = roundup(offset + size, PAGE_SIZE); 3309 3310 GIANT_REQUIRED; 3311 3312 va = kmem_alloc_pageable(kernel_map, size); 3313 if (!va) 3314 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3315 3316 pa = pa & PG_FRAME; 3317 for (tmpva = va; size > 0;) { 3318 pte = vtopte(tmpva); 3319 *pte = pa | PG_RW | PG_V | pgeflag; 3320 size -= PAGE_SIZE; 3321 tmpva += PAGE_SIZE; 3322 pa += PAGE_SIZE; 3323 } 3324 invltlb(); 3325 3326 return ((void *)(va + offset)); 3327} 3328 3329void 3330pmap_unmapdev(va, size) 3331 vm_offset_t va; 3332 vm_size_t size; 3333{ 3334 vm_offset_t base, offset; 3335 3336 base = va & PG_FRAME; 3337 offset = va & PAGE_MASK; 3338 size = roundup(offset + size, PAGE_SIZE); 3339 kmem_free(kernel_map, base, size); 3340} 3341 3342/* 3343 * perform the pmap work for mincore 3344 */ 3345int 3346pmap_mincore(pmap, addr) 3347 pmap_t pmap; 3348 vm_offset_t addr; 3349{ 3350 pt_entry_t *ptep, pte; 3351 vm_page_t m; 3352 int val = 0; 3353 3354 ptep = pmap_pte(pmap, addr); 3355 if (ptep == 0) { 3356 return 0; 3357 } 3358 3359 if ((pte = *ptep) != 0) { 3360 vm_offset_t pa; 3361 3362 val = MINCORE_INCORE; 3363 if ((pte & PG_MANAGED) == 0) 3364 return val; 3365 3366 pa = pte & PG_FRAME; 3367 3368 m = PHYS_TO_VM_PAGE(pa); 3369 3370 /* 3371 * Modified by us 3372 */ 3373 if (pte & PG_M) 3374 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3375 /* 3376 * Modified by someone 3377 */ 3378 else if (m->dirty || pmap_is_modified(m)) 3379 val |= MINCORE_MODIFIED_OTHER; 3380 /* 3381 * Referenced by us 3382 */ 3383 if (pte & PG_A) 3384 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3385 3386 /* 3387 * Referenced by someone 3388 */ 3389 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3390 val |= MINCORE_REFERENCED_OTHER; 3391 vm_page_flag_set(m, PG_REFERENCED); 3392 } 3393 } 3394 return val; 3395} 3396 3397void 3398pmap_activate(struct thread *td) 3399{ 3400 struct proc *p = td->td_proc; 3401 pmap_t pmap; 3402 u_int32_t cr3; 3403 3404 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3405#if defined(SMP) 3406 pmap->pm_active |= PCPU_GET(cpumask); 3407#else 3408 pmap->pm_active |= 1; 3409#endif 3410#if defined(SWTCH_OPTIM_STATS) 3411 tlb_flush_count++; 3412#endif 3413 cr3 = vtophys(pmap->pm_pdir); 3414 /* XXXKSE this is wrong. 3415 * pmap_activate is for the current thread on the current cpu 3416 */ 3417 if (p->p_flag & P_KSES) { 3418 /* Make sure all other cr3 entries are updated. */ 3419 /* what if they are running? XXXKSE (maybe abort them) */ 3420 FOREACH_THREAD_IN_PROC(p, td) { 3421 td->td_pcb->pcb_cr3 = cr3; 3422 } 3423 } else { 3424 td->td_pcb->pcb_cr3 = cr3; 3425 } 3426 load_cr3(cr3); 3427} 3428 3429vm_offset_t 3430pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3431{ 3432 3433 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3434 return addr; 3435 } 3436 3437 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3438 return addr; 3439} 3440 3441 3442#if defined(PMAP_DEBUG) 3443pmap_pid_dump(int pid) 3444{ 3445 pmap_t pmap; 3446 struct proc *p; 3447 int npte = 0; 3448 int index; 3449 3450 sx_slock(&allproc_lock); 3451 LIST_FOREACH(p, &allproc, p_list) { 3452 if (p->p_pid != pid) 3453 continue; 3454 3455 if (p->p_vmspace) { 3456 int i,j; 3457 index = 0; 3458 pmap = vmspace_pmap(p->p_vmspace); 3459 for (i = 0; i < NPDEPG; i++) { 3460 pd_entry_t *pde; 3461 pt_entry_t *pte; 3462 vm_offset_t base = i << PDRSHIFT; 3463 3464 pde = &pmap->pm_pdir[i]; 3465 if (pde && pmap_pde_v(pde)) { 3466 for (j = 0; j < NPTEPG; j++) { 3467 vm_offset_t va = base + (j << PAGE_SHIFT); 3468 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3469 if (index) { 3470 index = 0; 3471 printf("\n"); 3472 } 3473 sx_sunlock(&allproc_lock); 3474 return npte; 3475 } 3476 pte = pmap_pte_quick(pmap, va); 3477 if (pte && pmap_pte_v(pte)) { 3478 pt_entry_t pa; 3479 vm_page_t m; 3480 pa = *pte; 3481 m = PHYS_TO_VM_PAGE(pa); 3482 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3483 va, pa, m->hold_count, m->wire_count, m->flags); 3484 npte++; 3485 index++; 3486 if (index >= 2) { 3487 index = 0; 3488 printf("\n"); 3489 } else { 3490 printf(" "); 3491 } 3492 } 3493 } 3494 } 3495 } 3496 } 3497 } 3498 sx_sunlock(&allproc_lock); 3499 return npte; 3500} 3501#endif 3502 3503#if defined(DEBUG) 3504 3505static void pads(pmap_t pm); 3506void pmap_pvdump(vm_offset_t pa); 3507 3508/* print address space of pmap*/ 3509static void 3510pads(pm) 3511 pmap_t pm; 3512{ 3513 int i, j; 3514 vm_offset_t va; 3515 pt_entry_t *ptep; 3516 3517 if (pm == kernel_pmap) 3518 return; 3519 for (i = 0; i < NPDEPG; i++) 3520 if (pm->pm_pdir[i]) 3521 for (j = 0; j < NPTEPG; j++) { 3522 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3523 if (pm == kernel_pmap && va < KERNBASE) 3524 continue; 3525 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3526 continue; 3527 ptep = pmap_pte_quick(pm, va); 3528 if (pmap_pte_v(ptep)) 3529 printf("%x:%x ", va, *ptep); 3530 }; 3531 3532} 3533 3534void 3535pmap_pvdump(pa) 3536 vm_offset_t pa; 3537{ 3538 pv_entry_t pv; 3539 vm_page_t m; 3540 3541 printf("pa %x", pa); 3542 m = PHYS_TO_VM_PAGE(pa); 3543 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3544 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3545 pads(pv->pv_pmap); 3546 } 3547 printf(" "); 3548} 3549#endif 3550