pmap.c revision 99072
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 99072 2002-06-29 17:26:22Z 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 = 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#ifdef KSTACK_GUARD 1104 ks -= PAGE_SIZE; 1105 for (i = 1; i < (KSTACK_PAGES + 1); i++) { 1106#else 1107 for (i = 0; i < KSTACK_PAGES; i++) { 1108#endif 1109 m = vm_page_lookup(ksobj, i); 1110 if (m == NULL) 1111 panic("pmap_dispose_thread: kstack already missing?"); 1112 vm_page_busy(m); 1113 oldpte = *(ptek + i); 1114 *(ptek + i) = 0; 1115#ifndef I386_CPU 1116 invlpg(ks + i * PAGE_SIZE); 1117#endif 1118 vm_page_unwire(m, 0); 1119 vm_page_free(m); 1120 } 1121#ifdef I386_CPU 1122 invltlb(); 1123#endif 1124 /* 1125 * Free the space that this stack was mapped to in the kernel 1126 * address map. 1127 */ 1128#ifdef KSTACK_GUARD 1129 kmem_free(kernel_map, ks, (KSTACK_PAGES + 1) * PAGE_SIZE); 1130#else 1131 kmem_free(kernel_map, ks, KSTACK_PAGES * PAGE_SIZE); 1132#endif 1133 vm_object_deallocate(ksobj); 1134 td->td_kstack_obj = NULL; /* play it safe */ 1135} 1136 1137/* 1138 * Allow the Kernel stack for a thread to be prejudicially paged out. 1139 */ 1140void 1141pmap_swapout_thread(td) 1142 struct thread *td; 1143{ 1144 int i; 1145 vm_object_t ksobj; 1146 vm_offset_t ks; 1147 vm_page_t m; 1148 1149 ksobj = td->td_kstack_obj; 1150 ks = td->td_kstack; 1151 for (i = 0; i < KSTACK_PAGES; i++) { 1152 m = vm_page_lookup(ksobj, i); 1153 if (m == NULL) 1154 panic("pmap_swapout_thread: kstack already missing?"); 1155 vm_page_dirty(m); 1156 vm_page_unwire(m, 0); 1157 pmap_kremove(ks + i * PAGE_SIZE); 1158 } 1159} 1160 1161/* 1162 * Bring the kernel stack for a specified thread back in. 1163 */ 1164void 1165pmap_swapin_thread(td) 1166 struct thread *td; 1167{ 1168 int i, rv; 1169 vm_object_t ksobj; 1170 vm_offset_t ks; 1171 vm_page_t m; 1172 1173 ksobj = td->td_kstack_obj; 1174 ks = td->td_kstack; 1175 for (i = 0; i < KSTACK_PAGES; i++) { 1176 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1177 pmap_kenter(ks + i * PAGE_SIZE, VM_PAGE_TO_PHYS(m)); 1178 if (m->valid != VM_PAGE_BITS_ALL) { 1179 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1180 if (rv != VM_PAGER_OK) 1181 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1182 m = vm_page_lookup(ksobj, i); 1183 m->valid = VM_PAGE_BITS_ALL; 1184 } 1185 vm_page_wire(m); 1186 vm_page_wakeup(m); 1187 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 1188 } 1189} 1190 1191/*************************************************** 1192 * Page table page management routines..... 1193 ***************************************************/ 1194 1195/* 1196 * This routine unholds page table pages, and if the hold count 1197 * drops to zero, then it decrements the wire count. 1198 */ 1199static int 1200_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1201{ 1202 1203 while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) 1204 ; 1205 1206 if (m->hold_count == 0) { 1207 vm_offset_t pteva; 1208 /* 1209 * unmap the page table page 1210 */ 1211 pmap->pm_pdir[m->pindex] = 0; 1212 --pmap->pm_stats.resident_count; 1213 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1214 (PTDpde & PG_FRAME)) { 1215 /* 1216 * Do a invltlb to make the invalidated mapping 1217 * take effect immediately. 1218 */ 1219 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); 1220 pmap_invalidate_page(pmap, pteva); 1221 } 1222 1223 if (pmap->pm_ptphint == m) 1224 pmap->pm_ptphint = NULL; 1225 1226 /* 1227 * If the page is finally unwired, simply free it. 1228 */ 1229 --m->wire_count; 1230 if (m->wire_count == 0) { 1231 1232 vm_page_flash(m); 1233 vm_page_busy(m); 1234 vm_page_free_zero(m); 1235 --cnt.v_wire_count; 1236 } 1237 return 1; 1238 } 1239 return 0; 1240} 1241 1242static PMAP_INLINE int 1243pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1244{ 1245 vm_page_unhold(m); 1246 if (m->hold_count == 0) 1247 return _pmap_unwire_pte_hold(pmap, m); 1248 else 1249 return 0; 1250} 1251 1252/* 1253 * After removing a page table entry, this routine is used to 1254 * conditionally free the page, and manage the hold/wire counts. 1255 */ 1256static int 1257pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1258{ 1259 unsigned ptepindex; 1260 if (va >= VM_MAXUSER_ADDRESS) 1261 return 0; 1262 1263 if (mpte == NULL) { 1264 ptepindex = (va >> PDRSHIFT); 1265 if (pmap->pm_ptphint && 1266 (pmap->pm_ptphint->pindex == ptepindex)) { 1267 mpte = pmap->pm_ptphint; 1268 } else { 1269 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1270 pmap->pm_ptphint = mpte; 1271 } 1272 } 1273 1274 return pmap_unwire_pte_hold(pmap, mpte); 1275} 1276 1277void 1278pmap_pinit0(pmap) 1279 struct pmap *pmap; 1280{ 1281 pmap->pm_pdir = 1282 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1283 pmap_kenter((vm_offset_t) pmap->pm_pdir, (vm_offset_t) IdlePTD); 1284 pmap->pm_ptphint = NULL; 1285 pmap->pm_active = 0; 1286 TAILQ_INIT(&pmap->pm_pvlist); 1287 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1288 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1289} 1290 1291/* 1292 * Initialize a preallocated and zeroed pmap structure, 1293 * such as one in a vmspace structure. 1294 */ 1295void 1296pmap_pinit(pmap) 1297 register struct pmap *pmap; 1298{ 1299 vm_page_t ptdpg; 1300 1301 /* 1302 * No need to allocate page table space yet but we do need a valid 1303 * page directory table. 1304 */ 1305 if (pmap->pm_pdir == NULL) 1306 pmap->pm_pdir = 1307 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1308 1309 /* 1310 * allocate object for the ptes 1311 */ 1312 if (pmap->pm_pteobj == NULL) 1313 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1314 1315 /* 1316 * allocate the page directory page 1317 */ 1318 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1319 VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1320 1321 ptdpg->wire_count = 1; 1322 ++cnt.v_wire_count; 1323 1324 1325 vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/ 1326 ptdpg->valid = VM_PAGE_BITS_ALL; 1327 1328 pmap_kenter((vm_offset_t) pmap->pm_pdir, VM_PAGE_TO_PHYS(ptdpg)); 1329 if ((ptdpg->flags & PG_ZERO) == 0) 1330 bzero(pmap->pm_pdir, PAGE_SIZE); 1331 1332 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1333 /* Wire in kernel global address entries. */ 1334 /* XXX copies current process, does not fill in MPPTDI */ 1335 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1336#ifdef SMP 1337 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1338#endif 1339 1340 /* install self-referential address mapping entry */ 1341 pmap->pm_pdir[PTDPTDI] = 1342 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1343 1344 pmap->pm_active = 0; 1345 pmap->pm_ptphint = NULL; 1346 TAILQ_INIT(&pmap->pm_pvlist); 1347 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1348} 1349 1350/* 1351 * Wire in kernel global address entries. To avoid a race condition 1352 * between pmap initialization and pmap_growkernel, this procedure 1353 * should be called after the vmspace is attached to the process 1354 * but before this pmap is activated. 1355 */ 1356void 1357pmap_pinit2(pmap) 1358 struct pmap *pmap; 1359{ 1360 /* XXX: Remove this stub when no longer called */ 1361} 1362 1363static int 1364pmap_release_free_page(pmap_t pmap, vm_page_t p) 1365{ 1366 pd_entry_t *pde = pmap->pm_pdir; 1367 /* 1368 * This code optimizes the case of freeing non-busy 1369 * page-table pages. Those pages are zero now, and 1370 * might as well be placed directly into the zero queue. 1371 */ 1372 if (vm_page_sleep_busy(p, FALSE, "pmaprl")) 1373 return 0; 1374 1375 vm_page_busy(p); 1376 1377 /* 1378 * Remove the page table page from the processes address space. 1379 */ 1380 pde[p->pindex] = 0; 1381 pmap->pm_stats.resident_count--; 1382 1383 if (p->hold_count) { 1384 panic("pmap_release: freeing held page table page"); 1385 } 1386 /* 1387 * Page directory pages need to have the kernel 1388 * stuff cleared, so they can go into the zero queue also. 1389 */ 1390 if (p->pindex == PTDPTDI) { 1391 bzero(pde + KPTDI, nkpt * PTESIZE); 1392#ifdef SMP 1393 pde[MPPTDI] = 0; 1394#endif 1395 pde[APTDPTDI] = 0; 1396 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1397 } 1398 1399 if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex)) 1400 pmap->pm_ptphint = NULL; 1401 1402 p->wire_count--; 1403 cnt.v_wire_count--; 1404 vm_page_free_zero(p); 1405 return 1; 1406} 1407 1408/* 1409 * this routine is called if the page table page is not 1410 * mapped correctly. 1411 */ 1412static vm_page_t 1413_pmap_allocpte(pmap, ptepindex) 1414 pmap_t pmap; 1415 unsigned ptepindex; 1416{ 1417 vm_offset_t pteva, ptepa; /* XXXPA */ 1418 vm_page_t m; 1419 1420 /* 1421 * Find or fabricate a new pagetable page 1422 */ 1423 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1424 VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1425 1426 KASSERT(m->queue == PQ_NONE, 1427 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1428 1429 if (m->wire_count == 0) 1430 cnt.v_wire_count++; 1431 m->wire_count++; 1432 1433 /* 1434 * Increment the hold count for the page table page 1435 * (denoting a new mapping.) 1436 */ 1437 m->hold_count++; 1438 1439 /* 1440 * Map the pagetable page into the process address space, if 1441 * it isn't already there. 1442 */ 1443 1444 pmap->pm_stats.resident_count++; 1445 1446 ptepa = VM_PAGE_TO_PHYS(m); 1447 pmap->pm_pdir[ptepindex] = 1448 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1449 1450 /* 1451 * Set the page table hint 1452 */ 1453 pmap->pm_ptphint = m; 1454 1455 /* 1456 * Try to use the new mapping, but if we cannot, then 1457 * do it with the routine that maps the page explicitly. 1458 */ 1459 if ((m->flags & PG_ZERO) == 0) { 1460 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1461 (PTDpde & PG_FRAME)) { 1462 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1463 bzero((caddr_t) pteva, PAGE_SIZE); 1464 } else { 1465 pmap_zero_page(m); 1466 } 1467 } 1468 1469 m->valid = VM_PAGE_BITS_ALL; 1470 vm_page_flag_clear(m, PG_ZERO); 1471 vm_page_flag_set(m, PG_MAPPED); 1472 vm_page_wakeup(m); 1473 1474 return m; 1475} 1476 1477static vm_page_t 1478pmap_allocpte(pmap_t pmap, vm_offset_t va) 1479{ 1480 unsigned ptepindex; 1481 pd_entry_t ptepa; 1482 vm_page_t m; 1483 1484 /* 1485 * Calculate pagetable page index 1486 */ 1487 ptepindex = va >> PDRSHIFT; 1488 1489 /* 1490 * Get the page directory entry 1491 */ 1492 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1493 1494 /* 1495 * This supports switching from a 4MB page to a 1496 * normal 4K page. 1497 */ 1498 if (ptepa & PG_PS) { 1499 pmap->pm_pdir[ptepindex] = 0; 1500 ptepa = 0; 1501 invltlb(); 1502 } 1503 1504 /* 1505 * If the page table page is mapped, we just increment the 1506 * hold count, and activate it. 1507 */ 1508 if (ptepa) { 1509 /* 1510 * In order to get the page table page, try the 1511 * hint first. 1512 */ 1513 if (pmap->pm_ptphint && 1514 (pmap->pm_ptphint->pindex == ptepindex)) { 1515 m = pmap->pm_ptphint; 1516 } else { 1517 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1518 pmap->pm_ptphint = m; 1519 } 1520 m->hold_count++; 1521 return m; 1522 } 1523 /* 1524 * Here if the pte page isn't mapped, or if it has been deallocated. 1525 */ 1526 return _pmap_allocpte(pmap, ptepindex); 1527} 1528 1529 1530/*************************************************** 1531* Pmap allocation/deallocation routines. 1532 ***************************************************/ 1533 1534/* 1535 * Release any resources held by the given physical map. 1536 * Called when a pmap initialized by pmap_pinit is being released. 1537 * Should only be called if the map contains no valid mappings. 1538 */ 1539void 1540pmap_release(pmap_t pmap) 1541{ 1542 vm_page_t p,n,ptdpg; 1543 vm_object_t object = pmap->pm_pteobj; 1544 int curgeneration; 1545 1546#if defined(DIAGNOSTIC) 1547 if (object->ref_count != 1) 1548 panic("pmap_release: pteobj reference count != 1"); 1549#endif 1550 1551 ptdpg = NULL; 1552 LIST_REMOVE(pmap, pm_list); 1553retry: 1554 curgeneration = object->generation; 1555 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1556 n = TAILQ_NEXT(p, listq); 1557 if (p->pindex == PTDPTDI) { 1558 ptdpg = p; 1559 continue; 1560 } 1561 while (1) { 1562 if (!pmap_release_free_page(pmap, p) && 1563 (object->generation != curgeneration)) 1564 goto retry; 1565 } 1566 } 1567 1568 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1569 goto retry; 1570} 1571 1572static int 1573kvm_size(SYSCTL_HANDLER_ARGS) 1574{ 1575 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1576 1577 return sysctl_handle_long(oidp, &ksize, 0, req); 1578} 1579SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1580 0, 0, kvm_size, "IU", "Size of KVM"); 1581 1582static int 1583kvm_free(SYSCTL_HANDLER_ARGS) 1584{ 1585 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1586 1587 return sysctl_handle_long(oidp, &kfree, 0, req); 1588} 1589SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1590 0, 0, kvm_free, "IU", "Amount of KVM free"); 1591 1592/* 1593 * grow the number of kernel page table entries, if needed 1594 */ 1595void 1596pmap_growkernel(vm_offset_t addr) 1597{ 1598 struct pmap *pmap; 1599 int s; 1600 vm_offset_t ptppaddr; 1601 vm_page_t nkpg; 1602 pd_entry_t newpdir; 1603 1604 s = splhigh(); 1605 if (kernel_vm_end == 0) { 1606 kernel_vm_end = KERNBASE; 1607 nkpt = 0; 1608 while (pdir_pde(PTD, kernel_vm_end)) { 1609 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1610 nkpt++; 1611 } 1612 } 1613 addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1614 while (kernel_vm_end < addr) { 1615 if (pdir_pde(PTD, kernel_vm_end)) { 1616 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1617 continue; 1618 } 1619 1620 /* 1621 * This index is bogus, but out of the way 1622 */ 1623 nkpg = vm_page_alloc(kptobj, nkpt, VM_ALLOC_SYSTEM); 1624 if (!nkpg) 1625 panic("pmap_growkernel: no memory to grow kernel"); 1626 1627 nkpt++; 1628 1629 vm_page_wire(nkpg); 1630 pmap_zero_page(nkpg); 1631 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1632 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1633 pdir_pde(PTD, kernel_vm_end) = newpdir; 1634 1635 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1636 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1637 } 1638 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1639 } 1640 splx(s); 1641} 1642 1643 1644/*************************************************** 1645 * page management routines. 1646 ***************************************************/ 1647 1648/* 1649 * free the pv_entry back to the free list 1650 */ 1651static PMAP_INLINE void 1652free_pv_entry(pv_entry_t pv) 1653{ 1654 pv_entry_count--; 1655 uma_zfree(pvzone, pv); 1656} 1657 1658/* 1659 * get a new pv_entry, allocating a block from the system 1660 * when needed. 1661 * the memory allocation is performed bypassing the malloc code 1662 * because of the possibility of allocations at interrupt time. 1663 */ 1664static pv_entry_t 1665get_pv_entry(void) 1666{ 1667 pv_entry_count++; 1668 if (pv_entry_high_water && 1669 (pv_entry_count > pv_entry_high_water) && 1670 (pmap_pagedaemon_waken == 0)) { 1671 pmap_pagedaemon_waken = 1; 1672 wakeup (&vm_pages_needed); 1673 } 1674 return uma_zalloc(pvzone, M_NOWAIT); 1675} 1676 1677/* 1678 * This routine is very drastic, but can save the system 1679 * in a pinch. 1680 */ 1681void 1682pmap_collect() 1683{ 1684 int i; 1685 vm_page_t m; 1686 static int warningdone = 0; 1687 1688 if (pmap_pagedaemon_waken == 0) 1689 return; 1690 1691 if (warningdone < 5) { 1692 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1693 warningdone++; 1694 } 1695 1696 for(i = 0; i < vm_page_array_size; i++) { 1697 m = &vm_page_array[i]; 1698 if (m->wire_count || m->hold_count || m->busy || 1699 (m->flags & (PG_BUSY | PG_UNMANAGED))) 1700 continue; 1701 pmap_remove_all(m); 1702 } 1703 pmap_pagedaemon_waken = 0; 1704} 1705 1706 1707/* 1708 * If it is the first entry on the list, it is actually 1709 * in the header and we must copy the following entry up 1710 * to the header. Otherwise we must search the list for 1711 * the entry. In either case we free the now unused entry. 1712 */ 1713 1714static int 1715pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1716{ 1717 pv_entry_t pv; 1718 int rtval; 1719 int s; 1720 1721 s = splvm(); 1722 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1723 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1724 if (pmap == pv->pv_pmap && va == pv->pv_va) 1725 break; 1726 } 1727 } else { 1728 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1729 if (va == pv->pv_va) 1730 break; 1731 } 1732 } 1733 1734 rtval = 0; 1735 if (pv) { 1736 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1737 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1738 m->md.pv_list_count--; 1739 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1740 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1741 1742 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1743 free_pv_entry(pv); 1744 } 1745 1746 splx(s); 1747 return rtval; 1748} 1749 1750/* 1751 * Create a pv entry for page at pa for 1752 * (pmap, va). 1753 */ 1754static void 1755pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1756{ 1757 1758 int s; 1759 pv_entry_t pv; 1760 1761 s = splvm(); 1762 pv = get_pv_entry(); 1763 pv->pv_va = va; 1764 pv->pv_pmap = pmap; 1765 pv->pv_ptem = mpte; 1766 1767 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1768 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1769 m->md.pv_list_count++; 1770 1771 splx(s); 1772} 1773 1774/* 1775 * pmap_remove_pte: do the things to unmap a page in a process 1776 */ 1777static int 1778pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1779{ 1780 pt_entry_t oldpte; 1781 vm_page_t m; 1782 1783 oldpte = atomic_readandclear_int(ptq); 1784 if (oldpte & PG_W) 1785 pmap->pm_stats.wired_count -= 1; 1786 /* 1787 * Machines that don't support invlpg, also don't support 1788 * PG_G. 1789 */ 1790 if (oldpte & PG_G) 1791 invlpg(va); 1792 pmap->pm_stats.resident_count -= 1; 1793 if (oldpte & PG_MANAGED) { 1794 m = PHYS_TO_VM_PAGE(oldpte); 1795 if (oldpte & PG_M) { 1796#if defined(PMAP_DIAGNOSTIC) 1797 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1798 printf( 1799 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1800 va, oldpte); 1801 } 1802#endif 1803 if (pmap_track_modified(va)) 1804 vm_page_dirty(m); 1805 } 1806 if (oldpte & PG_A) 1807 vm_page_flag_set(m, PG_REFERENCED); 1808 return pmap_remove_entry(pmap, m, va); 1809 } else { 1810 return pmap_unuse_pt(pmap, va, NULL); 1811 } 1812 1813 return 0; 1814} 1815 1816/* 1817 * Remove a single page from a process address space 1818 */ 1819static void 1820pmap_remove_page(pmap_t pmap, vm_offset_t va) 1821{ 1822 register pt_entry_t *ptq; 1823 1824 /* 1825 * if there is no pte for this address, just skip it!!! 1826 */ 1827 if (*pmap_pde(pmap, va) == 0) { 1828 return; 1829 } 1830 1831 /* 1832 * get a local va for mappings for this pmap. 1833 */ 1834 ptq = get_ptbase(pmap) + i386_btop(va); 1835 if (*ptq) { 1836 (void) pmap_remove_pte(pmap, ptq, va); 1837 pmap_invalidate_page(pmap, va); 1838 } 1839 return; 1840} 1841 1842/* 1843 * Remove the given range of addresses from the specified map. 1844 * 1845 * It is assumed that the start and end are properly 1846 * rounded to the page size. 1847 */ 1848void 1849pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1850{ 1851 register pt_entry_t *ptbase; 1852 vm_offset_t pdnxt; 1853 pd_entry_t ptpaddr; 1854 vm_offset_t sindex, eindex; 1855 int anyvalid; 1856 1857 if (pmap == NULL) 1858 return; 1859 1860 if (pmap->pm_stats.resident_count == 0) 1861 return; 1862 1863 /* 1864 * special handling of removing one page. a very 1865 * common operation and easy to short circuit some 1866 * code. 1867 */ 1868 if ((sva + PAGE_SIZE == eva) && 1869 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1870 pmap_remove_page(pmap, sva); 1871 return; 1872 } 1873 1874 anyvalid = 0; 1875 1876 /* 1877 * Get a local virtual address for the mappings that are being 1878 * worked with. 1879 */ 1880 ptbase = get_ptbase(pmap); 1881 1882 sindex = i386_btop(sva); 1883 eindex = i386_btop(eva); 1884 1885 for (; sindex < eindex; sindex = pdnxt) { 1886 unsigned pdirindex; 1887 1888 /* 1889 * Calculate index for next page table. 1890 */ 1891 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1892 if (pmap->pm_stats.resident_count == 0) 1893 break; 1894 1895 pdirindex = sindex / NPDEPG; 1896 ptpaddr = pmap->pm_pdir[pdirindex]; 1897 if ((ptpaddr & PG_PS) != 0) { 1898 pmap->pm_pdir[pdirindex] = 0; 1899 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1900 anyvalid++; 1901 continue; 1902 } 1903 1904 /* 1905 * Weed out invalid mappings. Note: we assume that the page 1906 * directory table is always allocated, and in kernel virtual. 1907 */ 1908 if (ptpaddr == 0) 1909 continue; 1910 1911 /* 1912 * Limit our scan to either the end of the va represented 1913 * by the current page table page, or to the end of the 1914 * range being removed. 1915 */ 1916 if (pdnxt > eindex) { 1917 pdnxt = eindex; 1918 } 1919 1920 for (; sindex != pdnxt; sindex++) { 1921 vm_offset_t va; 1922 if (ptbase[sindex] == 0) { 1923 continue; 1924 } 1925 va = i386_ptob(sindex); 1926 1927 anyvalid++; 1928 if (pmap_remove_pte(pmap, 1929 ptbase + sindex, va)) 1930 break; 1931 } 1932 } 1933 1934 if (anyvalid) 1935 pmap_invalidate_all(pmap); 1936} 1937 1938/* 1939 * Routine: pmap_remove_all 1940 * Function: 1941 * Removes this physical page from 1942 * all physical maps in which it resides. 1943 * Reflects back modify bits to the pager. 1944 * 1945 * Notes: 1946 * Original versions of this routine were very 1947 * inefficient because they iteratively called 1948 * pmap_remove (slow...) 1949 */ 1950 1951static void 1952pmap_remove_all(vm_page_t m) 1953{ 1954 register pv_entry_t pv; 1955 pt_entry_t *pte, tpte; 1956 int s; 1957 1958#if defined(PMAP_DIAGNOSTIC) 1959 /* 1960 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1961 * pages! 1962 */ 1963 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1964 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1965 } 1966#endif 1967 1968 s = splvm(); 1969 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1970 pv->pv_pmap->pm_stats.resident_count--; 1971 1972 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1973 1974 tpte = atomic_readandclear_int(pte); 1975 if (tpte & PG_W) 1976 pv->pv_pmap->pm_stats.wired_count--; 1977 1978 if (tpte & PG_A) 1979 vm_page_flag_set(m, PG_REFERENCED); 1980 1981 /* 1982 * Update the vm_page_t clean and reference bits. 1983 */ 1984 if (tpte & PG_M) { 1985#if defined(PMAP_DIAGNOSTIC) 1986 if (pmap_nw_modified((pt_entry_t) tpte)) { 1987 printf( 1988 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1989 pv->pv_va, tpte); 1990 } 1991#endif 1992 if (pmap_track_modified(pv->pv_va)) 1993 vm_page_dirty(m); 1994 } 1995 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1996 1997 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1998 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1999 m->md.pv_list_count--; 2000 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 2001 free_pv_entry(pv); 2002 } 2003 2004 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 2005 2006 splx(s); 2007} 2008 2009/* 2010 * Set the physical protection on the 2011 * specified range of this map as requested. 2012 */ 2013void 2014pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 2015{ 2016 register pt_entry_t *ptbase; 2017 vm_offset_t pdnxt; 2018 pd_entry_t ptpaddr; 2019 vm_offset_t sindex, eindex; 2020 int anychanged; 2021 2022 if (pmap == NULL) 2023 return; 2024 2025 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 2026 pmap_remove(pmap, sva, eva); 2027 return; 2028 } 2029 2030 if (prot & VM_PROT_WRITE) 2031 return; 2032 2033 anychanged = 0; 2034 2035 ptbase = get_ptbase(pmap); 2036 2037 sindex = i386_btop(sva); 2038 eindex = i386_btop(eva); 2039 2040 for (; sindex < eindex; sindex = pdnxt) { 2041 2042 unsigned pdirindex; 2043 2044 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 2045 2046 pdirindex = sindex / NPDEPG; 2047 ptpaddr = pmap->pm_pdir[pdirindex]; 2048 if ((ptpaddr & PG_PS) != 0) { 2049 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 2050 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 2051 anychanged++; 2052 continue; 2053 } 2054 2055 /* 2056 * Weed out invalid mappings. Note: we assume that the page 2057 * directory table is always allocated, and in kernel virtual. 2058 */ 2059 if (ptpaddr == 0) 2060 continue; 2061 2062 if (pdnxt > eindex) { 2063 pdnxt = eindex; 2064 } 2065 2066 for (; sindex != pdnxt; sindex++) { 2067 2068 pt_entry_t pbits; 2069 vm_page_t m; 2070 2071 pbits = ptbase[sindex]; 2072 2073 if (pbits & PG_MANAGED) { 2074 m = NULL; 2075 if (pbits & PG_A) { 2076 m = PHYS_TO_VM_PAGE(pbits); 2077 vm_page_flag_set(m, PG_REFERENCED); 2078 pbits &= ~PG_A; 2079 } 2080 if (pbits & PG_M) { 2081 if (pmap_track_modified(i386_ptob(sindex))) { 2082 if (m == NULL) 2083 m = PHYS_TO_VM_PAGE(pbits); 2084 vm_page_dirty(m); 2085 pbits &= ~PG_M; 2086 } 2087 } 2088 } 2089 2090 pbits &= ~PG_RW; 2091 2092 if (pbits != ptbase[sindex]) { 2093 ptbase[sindex] = pbits; 2094 anychanged = 1; 2095 } 2096 } 2097 } 2098 if (anychanged) 2099 pmap_invalidate_all(pmap); 2100} 2101 2102/* 2103 * Insert the given physical page (p) at 2104 * the specified virtual address (v) in the 2105 * target physical map with the protection requested. 2106 * 2107 * If specified, the page will be wired down, meaning 2108 * that the related pte can not be reclaimed. 2109 * 2110 * NB: This is the only routine which MAY NOT lazy-evaluate 2111 * or lose information. That is, this routine must actually 2112 * insert this page into the given map NOW. 2113 */ 2114void 2115pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2116 boolean_t wired) 2117{ 2118 vm_offset_t pa; 2119 register pt_entry_t *pte; 2120 vm_offset_t opa; 2121 pt_entry_t origpte, newpte; 2122 vm_page_t mpte; 2123 2124 if (pmap == NULL) 2125 return; 2126 2127 va &= PG_FRAME; 2128#ifdef PMAP_DIAGNOSTIC 2129 if (va > VM_MAX_KERNEL_ADDRESS) 2130 panic("pmap_enter: toobig"); 2131 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2132 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2133#endif 2134 2135 mpte = NULL; 2136 /* 2137 * In the case that a page table page is not 2138 * resident, we are creating it here. 2139 */ 2140 if (va < VM_MAXUSER_ADDRESS) { 2141 mpte = pmap_allocpte(pmap, va); 2142 } 2143#if 0 && defined(PMAP_DIAGNOSTIC) 2144 else { 2145 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2146 origpte = *pdeaddr; 2147 if ((origpte & PG_V) == 0) { 2148 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2149 pmap->pm_pdir[PTDPTDI], origpte, va); 2150 } 2151 } 2152#endif 2153 2154 pte = pmap_pte(pmap, va); 2155 2156 /* 2157 * Page Directory table entry not valid, we need a new PT page 2158 */ 2159 if (pte == NULL) { 2160 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2161 (void *)pmap->pm_pdir[PTDPTDI], va); 2162 } 2163 2164 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2165 origpte = *(vm_offset_t *)pte; 2166 opa = origpte & PG_FRAME; 2167 2168 if (origpte & PG_PS) 2169 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2170 2171 /* 2172 * Mapping has not changed, must be protection or wiring change. 2173 */ 2174 if (origpte && (opa == pa)) { 2175 /* 2176 * Wiring change, just update stats. We don't worry about 2177 * wiring PT pages as they remain resident as long as there 2178 * are valid mappings in them. Hence, if a user page is wired, 2179 * the PT page will be also. 2180 */ 2181 if (wired && ((origpte & PG_W) == 0)) 2182 pmap->pm_stats.wired_count++; 2183 else if (!wired && (origpte & PG_W)) 2184 pmap->pm_stats.wired_count--; 2185 2186#if defined(PMAP_DIAGNOSTIC) 2187 if (pmap_nw_modified((pt_entry_t) origpte)) { 2188 printf( 2189 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2190 va, origpte); 2191 } 2192#endif 2193 2194 /* 2195 * Remove extra pte reference 2196 */ 2197 if (mpte) 2198 mpte->hold_count--; 2199 2200 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2201 if ((origpte & PG_RW) == 0) { 2202 *pte |= PG_RW; 2203#ifdef SMP 2204 cpu_invlpg((void *)va); 2205 if (pmap->pm_active & PCPU_GET(other_cpus)) 2206 smp_invltlb(); 2207#else 2208 invltlb_1pg(va); 2209#endif 2210 } 2211 return; 2212 } 2213 2214 /* 2215 * We might be turning off write access to the page, 2216 * so we go ahead and sense modify status. 2217 */ 2218 if (origpte & PG_MANAGED) { 2219 if ((origpte & PG_M) && pmap_track_modified(va)) { 2220 vm_page_t om; 2221 om = PHYS_TO_VM_PAGE(opa); 2222 vm_page_dirty(om); 2223 } 2224 pa |= PG_MANAGED; 2225 } 2226 goto validate; 2227 } 2228 /* 2229 * Mapping has changed, invalidate old range and fall through to 2230 * handle validating new mapping. 2231 */ 2232 if (opa) { 2233 int err; 2234 err = pmap_remove_pte(pmap, pte, va); 2235 if (err) 2236 panic("pmap_enter: pte vanished, va: 0x%x", va); 2237 } 2238 2239 /* 2240 * Enter on the PV list if part of our managed memory. Note that we 2241 * raise IPL while manipulating pv_table since pmap_enter can be 2242 * called at interrupt time. 2243 */ 2244 if (pmap_initialized && 2245 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2246 pmap_insert_entry(pmap, va, mpte, m); 2247 pa |= PG_MANAGED; 2248 } 2249 2250 /* 2251 * Increment counters 2252 */ 2253 pmap->pm_stats.resident_count++; 2254 if (wired) 2255 pmap->pm_stats.wired_count++; 2256 2257validate: 2258 /* 2259 * Now validate mapping with desired protection/wiring. 2260 */ 2261 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2262 2263 if (wired) 2264 newpte |= PG_W; 2265 if (va < VM_MAXUSER_ADDRESS) 2266 newpte |= PG_U; 2267 if (pmap == kernel_pmap) 2268 newpte |= pgeflag; 2269 2270 /* 2271 * if the mapping or permission bits are different, we need 2272 * to update the pte. 2273 */ 2274 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2275 *pte = newpte | PG_A; 2276 /*if (origpte)*/ { 2277#ifdef SMP 2278 cpu_invlpg((void *)va); 2279 if (pmap->pm_active & PCPU_GET(other_cpus)) 2280 smp_invltlb(); 2281#else 2282 invltlb_1pg(va); 2283#endif 2284 } 2285 } 2286} 2287 2288/* 2289 * this code makes some *MAJOR* assumptions: 2290 * 1. Current pmap & pmap exists. 2291 * 2. Not wired. 2292 * 3. Read access. 2293 * 4. No page table pages. 2294 * 5. Tlbflush is deferred to calling procedure. 2295 * 6. Page IS managed. 2296 * but is *MUCH* faster than pmap_enter... 2297 */ 2298 2299static vm_page_t 2300pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2301{ 2302 pt_entry_t *pte; 2303 vm_offset_t pa; 2304 2305 /* 2306 * In the case that a page table page is not 2307 * resident, we are creating it here. 2308 */ 2309 if (va < VM_MAXUSER_ADDRESS) { 2310 unsigned ptepindex; 2311 pd_entry_t ptepa; 2312 2313 /* 2314 * Calculate pagetable page index 2315 */ 2316 ptepindex = va >> PDRSHIFT; 2317 if (mpte && (mpte->pindex == ptepindex)) { 2318 mpte->hold_count++; 2319 } else { 2320retry: 2321 /* 2322 * Get the page directory entry 2323 */ 2324 ptepa = pmap->pm_pdir[ptepindex]; 2325 2326 /* 2327 * If the page table page is mapped, we just increment 2328 * the hold count, and activate it. 2329 */ 2330 if (ptepa) { 2331 if (ptepa & PG_PS) 2332 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2333 if (pmap->pm_ptphint && 2334 (pmap->pm_ptphint->pindex == ptepindex)) { 2335 mpte = pmap->pm_ptphint; 2336 } else { 2337 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2338 pmap->pm_ptphint = mpte; 2339 } 2340 if (mpte == NULL) 2341 goto retry; 2342 mpte->hold_count++; 2343 } else { 2344 mpte = _pmap_allocpte(pmap, ptepindex); 2345 } 2346 } 2347 } else { 2348 mpte = NULL; 2349 } 2350 2351 /* 2352 * This call to vtopte makes the assumption that we are 2353 * entering the page into the current pmap. In order to support 2354 * quick entry into any pmap, one would likely use pmap_pte_quick. 2355 * But that isn't as quick as vtopte. 2356 */ 2357 pte = vtopte(va); 2358 if (*pte) { 2359 if (mpte) 2360 pmap_unwire_pte_hold(pmap, mpte); 2361 return 0; 2362 } 2363 2364 /* 2365 * Enter on the PV list if part of our managed memory. Note that we 2366 * raise IPL while manipulating pv_table since pmap_enter can be 2367 * called at interrupt time. 2368 */ 2369 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2370 pmap_insert_entry(pmap, va, mpte, m); 2371 2372 /* 2373 * Increment counters 2374 */ 2375 pmap->pm_stats.resident_count++; 2376 2377 pa = VM_PAGE_TO_PHYS(m); 2378 2379 /* 2380 * Now validate mapping with RO protection 2381 */ 2382 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2383 *pte = pa | PG_V | PG_U; 2384 else 2385 *pte = pa | PG_V | PG_U | PG_MANAGED; 2386 2387 return mpte; 2388} 2389 2390/* 2391 * Make a temporary mapping for a physical address. This is only intended 2392 * to be used for panic dumps. 2393 */ 2394void * 2395pmap_kenter_temporary(vm_offset_t pa, int i) 2396{ 2397 pmap_kenter((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa); 2398 return ((void *)crashdumpmap); 2399} 2400 2401#define MAX_INIT_PT (96) 2402/* 2403 * pmap_object_init_pt preloads the ptes for a given object 2404 * into the specified pmap. This eliminates the blast of soft 2405 * faults on process startup and immediately after an mmap. 2406 */ 2407void 2408pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2409 vm_object_t object, vm_pindex_t pindex, 2410 vm_size_t size, int limit) 2411{ 2412 vm_offset_t tmpidx; 2413 int psize; 2414 vm_page_t p, mpte; 2415 int objpgs; 2416 2417 if (pmap == NULL || object == NULL) 2418 return; 2419 2420 /* 2421 * This code maps large physical mmap regions into the 2422 * processor address space. Note that some shortcuts 2423 * are taken, but the code works. 2424 */ 2425 if (pseflag && (object->type == OBJT_DEVICE) && 2426 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2427 int i; 2428 vm_page_t m[1]; 2429 unsigned int ptepindex; 2430 int npdes; 2431 pd_entry_t ptepa; 2432 2433 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2434 return; 2435 2436retry: 2437 p = vm_page_lookup(object, pindex); 2438 if (p && vm_page_sleep_busy(p, FALSE, "init4p")) 2439 goto retry; 2440 2441 if (p == NULL) { 2442 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2443 if (p == NULL) 2444 return; 2445 m[0] = p; 2446 2447 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2448 vm_page_free(p); 2449 return; 2450 } 2451 2452 p = vm_page_lookup(object, pindex); 2453 vm_page_wakeup(p); 2454 } 2455 2456 ptepa = VM_PAGE_TO_PHYS(p); 2457 if (ptepa & (NBPDR - 1)) { 2458 return; 2459 } 2460 2461 p->valid = VM_PAGE_BITS_ALL; 2462 2463 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2464 npdes = size >> PDRSHIFT; 2465 for(i = 0; i < npdes; i++) { 2466 pmap->pm_pdir[ptepindex] = 2467 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2468 ptepa += NBPDR; 2469 ptepindex += 1; 2470 } 2471 vm_page_flag_set(p, PG_MAPPED); 2472 invltlb(); 2473 return; 2474 } 2475 2476 psize = i386_btop(size); 2477 2478 if ((object->type != OBJT_VNODE) || 2479 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2480 (object->resident_page_count > MAX_INIT_PT))) { 2481 return; 2482 } 2483 2484 if (psize + pindex > object->size) { 2485 if (object->size < pindex) 2486 return; 2487 psize = object->size - pindex; 2488 } 2489 2490 mpte = NULL; 2491 /* 2492 * if we are processing a major portion of the object, then scan the 2493 * entire thing. 2494 */ 2495 if (psize > (object->resident_page_count >> 2)) { 2496 objpgs = psize; 2497 2498 for (p = TAILQ_FIRST(&object->memq); 2499 ((objpgs > 0) && (p != NULL)); 2500 p = TAILQ_NEXT(p, listq)) { 2501 2502 if (p->pindex < pindex || p->pindex - pindex >= psize) { 2503 continue; 2504 } 2505 tmpidx = p->pindex - pindex; 2506 /* 2507 * don't allow an madvise to blow away our really 2508 * free pages allocating pv entries. 2509 */ 2510 if ((limit & MAP_PREFAULT_MADVISE) && 2511 cnt.v_free_count < cnt.v_free_reserved) { 2512 break; 2513 } 2514 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2515 (p->busy == 0) && 2516 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2517 if ((p->queue - p->pc) == PQ_CACHE) 2518 vm_page_deactivate(p); 2519 vm_page_busy(p); 2520 mpte = pmap_enter_quick(pmap, 2521 addr + i386_ptob(tmpidx), p, mpte); 2522 vm_page_flag_set(p, PG_MAPPED); 2523 vm_page_wakeup(p); 2524 } 2525 objpgs -= 1; 2526 } 2527 } else { 2528 /* 2529 * else lookup the pages one-by-one. 2530 */ 2531 for (tmpidx = 0; tmpidx < psize; tmpidx += 1) { 2532 /* 2533 * don't allow an madvise to blow away our really 2534 * free pages allocating pv entries. 2535 */ 2536 if ((limit & MAP_PREFAULT_MADVISE) && 2537 cnt.v_free_count < cnt.v_free_reserved) { 2538 break; 2539 } 2540 p = vm_page_lookup(object, tmpidx + pindex); 2541 if (p && 2542 ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2543 (p->busy == 0) && 2544 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2545 if ((p->queue - p->pc) == PQ_CACHE) 2546 vm_page_deactivate(p); 2547 vm_page_busy(p); 2548 mpte = pmap_enter_quick(pmap, 2549 addr + i386_ptob(tmpidx), p, mpte); 2550 vm_page_flag_set(p, PG_MAPPED); 2551 vm_page_wakeup(p); 2552 } 2553 } 2554 } 2555 return; 2556} 2557 2558/* 2559 * pmap_prefault provides a quick way of clustering 2560 * pagefaults into a processes address space. It is a "cousin" 2561 * of pmap_object_init_pt, except it runs at page fault time instead 2562 * of mmap time. 2563 */ 2564#define PFBAK 4 2565#define PFFOR 4 2566#define PAGEORDER_SIZE (PFBAK+PFFOR) 2567 2568static int pmap_prefault_pageorder[] = { 2569 -PAGE_SIZE, PAGE_SIZE, 2570 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2571 -3 * PAGE_SIZE, 3 * PAGE_SIZE 2572 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2573}; 2574 2575void 2576pmap_prefault(pmap, addra, entry) 2577 pmap_t pmap; 2578 vm_offset_t addra; 2579 vm_map_entry_t entry; 2580{ 2581 int i; 2582 vm_offset_t starta; 2583 vm_offset_t addr; 2584 vm_pindex_t pindex; 2585 vm_page_t m, mpte; 2586 vm_object_t object; 2587 2588 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2589 return; 2590 2591 object = entry->object.vm_object; 2592 2593 starta = addra - PFBAK * PAGE_SIZE; 2594 if (starta < entry->start) { 2595 starta = entry->start; 2596 } else if (starta > addra) { 2597 starta = 0; 2598 } 2599 2600 mpte = NULL; 2601 for (i = 0; i < PAGEORDER_SIZE; i++) { 2602 vm_object_t lobject; 2603 pt_entry_t *pte; 2604 2605 addr = addra + pmap_prefault_pageorder[i]; 2606 if (addr > addra + (PFFOR * PAGE_SIZE)) 2607 addr = 0; 2608 2609 if (addr < starta || addr >= entry->end) 2610 continue; 2611 2612 if ((*pmap_pde(pmap, addr)) == NULL) 2613 continue; 2614 2615 pte = vtopte(addr); 2616 if (*pte) 2617 continue; 2618 2619 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2620 lobject = object; 2621 for (m = vm_page_lookup(lobject, pindex); 2622 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2623 lobject = lobject->backing_object) { 2624 if (lobject->backing_object_offset & PAGE_MASK) 2625 break; 2626 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2627 m = vm_page_lookup(lobject->backing_object, pindex); 2628 } 2629 2630 /* 2631 * give-up when a page is not in memory 2632 */ 2633 if (m == NULL) 2634 break; 2635 2636 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2637 (m->busy == 0) && 2638 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2639 2640 if ((m->queue - m->pc) == PQ_CACHE) { 2641 vm_page_deactivate(m); 2642 } 2643 vm_page_busy(m); 2644 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2645 vm_page_flag_set(m, PG_MAPPED); 2646 vm_page_wakeup(m); 2647 } 2648 } 2649} 2650 2651/* 2652 * Routine: pmap_change_wiring 2653 * Function: Change the wiring attribute for a map/virtual-address 2654 * pair. 2655 * In/out conditions: 2656 * The mapping must already exist in the pmap. 2657 */ 2658void 2659pmap_change_wiring(pmap, va, wired) 2660 register pmap_t pmap; 2661 vm_offset_t va; 2662 boolean_t wired; 2663{ 2664 register pt_entry_t *pte; 2665 2666 if (pmap == NULL) 2667 return; 2668 2669 pte = pmap_pte(pmap, va); 2670 2671 if (wired && !pmap_pte_w(pte)) 2672 pmap->pm_stats.wired_count++; 2673 else if (!wired && pmap_pte_w(pte)) 2674 pmap->pm_stats.wired_count--; 2675 2676 /* 2677 * Wiring is not a hardware characteristic so there is no need to 2678 * invalidate TLB. 2679 */ 2680 pmap_pte_set_w(pte, wired); 2681} 2682 2683 2684 2685/* 2686 * Copy the range specified by src_addr/len 2687 * from the source map to the range dst_addr/len 2688 * in the destination map. 2689 * 2690 * This routine is only advisory and need not do anything. 2691 */ 2692 2693void 2694pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2695 vm_offset_t src_addr) 2696{ 2697 vm_offset_t addr; 2698 vm_offset_t end_addr = src_addr + len; 2699 vm_offset_t pdnxt; 2700 pd_entry_t src_frame, dst_frame; 2701 vm_page_t m; 2702 pd_entry_t saved_pde; 2703 2704 if (dst_addr != src_addr) 2705 return; 2706 2707 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2708 if (src_frame != (PTDpde & PG_FRAME)) 2709 return; 2710 2711 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2712 if (dst_frame != (APTDpde & PG_FRAME)) { 2713 APTDpde = dst_frame | PG_RW | PG_V; 2714#if defined(SMP) 2715 /* The page directory is not shared between CPUs */ 2716 cpu_invltlb(); 2717#else 2718 invltlb(); 2719#endif 2720 } 2721 saved_pde = APTDpde & (PG_FRAME | PG_RW | PG_V); 2722 for(addr = src_addr; addr < end_addr; addr = pdnxt) { 2723 pt_entry_t *src_pte, *dst_pte; 2724 vm_page_t dstmpte, srcmpte; 2725 pd_entry_t srcptepaddr; 2726 unsigned ptepindex; 2727 2728 if (addr >= UPT_MIN_ADDRESS) 2729 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2730 2731 /* 2732 * Don't let optional prefaulting of pages make us go 2733 * way below the low water mark of free pages or way 2734 * above high water mark of used pv entries. 2735 */ 2736 if (cnt.v_free_count < cnt.v_free_reserved || 2737 pv_entry_count > pv_entry_high_water) 2738 break; 2739 2740 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2741 ptepindex = addr >> PDRSHIFT; 2742 2743 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2744 if (srcptepaddr == 0) 2745 continue; 2746 2747 if (srcptepaddr & PG_PS) { 2748 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2749 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2750 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2751 } 2752 continue; 2753 } 2754 2755 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2756 if ((srcmpte == NULL) || 2757 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2758 continue; 2759 2760 if (pdnxt > end_addr) 2761 pdnxt = end_addr; 2762 2763 src_pte = vtopte(addr); 2764 dst_pte = avtopte(addr); 2765 while (addr < pdnxt) { 2766 pt_entry_t ptetemp; 2767 ptetemp = *src_pte; 2768 /* 2769 * we only virtual copy managed pages 2770 */ 2771 if ((ptetemp & PG_MANAGED) != 0) { 2772 /* 2773 * We have to check after allocpte for the 2774 * pte still being around... allocpte can 2775 * block. 2776 */ 2777 dstmpte = pmap_allocpte(dst_pmap, addr); 2778 if ((APTDpde & PG_FRAME) != 2779 (saved_pde & PG_FRAME)) { 2780 APTDpde = saved_pde; 2781printf ("IT HAPPENNED!"); 2782#if defined(SMP) 2783 cpu_invltlb(); 2784#else 2785 invltlb(); 2786#endif 2787 } 2788 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2789 /* 2790 * Clear the modified and 2791 * accessed (referenced) bits 2792 * during the copy. 2793 */ 2794 m = PHYS_TO_VM_PAGE(ptetemp); 2795 *dst_pte = ptetemp & ~(PG_M | PG_A); 2796 dst_pmap->pm_stats.resident_count++; 2797 pmap_insert_entry(dst_pmap, addr, 2798 dstmpte, m); 2799 } else { 2800 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2801 } 2802 if (dstmpte->hold_count >= srcmpte->hold_count) 2803 break; 2804 } 2805 addr += PAGE_SIZE; 2806 src_pte++; 2807 dst_pte++; 2808 } 2809 } 2810} 2811 2812/* 2813 * pmap_zero_page zeros the specified hardware page by mapping 2814 * the page into KVM and using bzero to clear its contents. 2815 */ 2816void 2817pmap_zero_page(vm_page_t m) 2818{ 2819 vm_offset_t phys = VM_PAGE_TO_PHYS(m); 2820 2821 if (*CMAP2) 2822 panic("pmap_zero_page: CMAP2 busy"); 2823 2824 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2825 invltlb_1pg((vm_offset_t)CADDR2); 2826 2827#if defined(I686_CPU) 2828 if (cpu_class == CPUCLASS_686) 2829 i686_pagezero(CADDR2); 2830 else 2831#endif 2832 bzero(CADDR2, PAGE_SIZE); 2833 *CMAP2 = 0; 2834} 2835 2836/* 2837 * pmap_zero_page_area zeros the specified hardware page by mapping 2838 * the page into KVM and using bzero to clear its contents. 2839 * 2840 * off and size may not cover an area beyond a single hardware page. 2841 */ 2842void 2843pmap_zero_page_area(vm_page_t m, int off, int size) 2844{ 2845 vm_offset_t phys = VM_PAGE_TO_PHYS(m); 2846 2847 if (*CMAP2) 2848 panic("pmap_zero_page: CMAP2 busy"); 2849 2850 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2851 invltlb_1pg((vm_offset_t)CADDR2); 2852 2853#if defined(I686_CPU) 2854 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2855 i686_pagezero(CADDR2); 2856 else 2857#endif 2858 bzero((char *)CADDR2 + off, size); 2859 *CMAP2 = 0; 2860} 2861 2862/* 2863 * pmap_copy_page copies the specified (machine independent) 2864 * page by mapping the page into virtual memory and using 2865 * bcopy to copy the page, one machine dependent page at a 2866 * time. 2867 */ 2868void 2869pmap_copy_page(vm_page_t src, vm_page_t dst) 2870{ 2871 2872 if (*CMAP1) 2873 panic("pmap_copy_page: CMAP1 busy"); 2874 if (*CMAP2) 2875 panic("pmap_copy_page: CMAP2 busy"); 2876 2877 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2878 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2879#ifdef I386_CPU 2880 invltlb(); 2881#else 2882 invlpg((u_int)CADDR1); 2883 invlpg((u_int)CADDR2); 2884#endif 2885 2886 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2887 2888 *CMAP1 = 0; 2889 *CMAP2 = 0; 2890} 2891 2892 2893/* 2894 * Routine: pmap_pageable 2895 * Function: 2896 * Make the specified pages (by pmap, offset) 2897 * pageable (or not) as requested. 2898 * 2899 * A page which is not pageable may not take 2900 * a fault; therefore, its page table entry 2901 * must remain valid for the duration. 2902 * 2903 * This routine is merely advisory; pmap_enter 2904 * will specify that these pages are to be wired 2905 * down (or not) as appropriate. 2906 */ 2907void 2908pmap_pageable(pmap, sva, eva, pageable) 2909 pmap_t pmap; 2910 vm_offset_t sva, eva; 2911 boolean_t pageable; 2912{ 2913} 2914 2915/* 2916 * Returns true if the pmap's pv is one of the first 2917 * 16 pvs linked to from this page. This count may 2918 * be changed upwards or downwards in the future; it 2919 * is only necessary that true be returned for a small 2920 * subset of pmaps for proper page aging. 2921 */ 2922boolean_t 2923pmap_page_exists_quick(pmap, m) 2924 pmap_t pmap; 2925 vm_page_t m; 2926{ 2927 pv_entry_t pv; 2928 int loops = 0; 2929 int s; 2930 2931 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2932 return FALSE; 2933 2934 s = splvm(); 2935 2936 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2937 if (pv->pv_pmap == pmap) { 2938 splx(s); 2939 return TRUE; 2940 } 2941 loops++; 2942 if (loops >= 16) 2943 break; 2944 } 2945 splx(s); 2946 return (FALSE); 2947} 2948 2949#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2950/* 2951 * Remove all pages from specified address space 2952 * this aids process exit speeds. Also, this code 2953 * is special cased for current process only, but 2954 * can have the more generic (and slightly slower) 2955 * mode enabled. This is much faster than pmap_remove 2956 * in the case of running down an entire address space. 2957 */ 2958void 2959pmap_remove_pages(pmap, sva, eva) 2960 pmap_t pmap; 2961 vm_offset_t sva, eva; 2962{ 2963 pt_entry_t *pte, tpte; 2964 vm_page_t m; 2965 pv_entry_t pv, npv; 2966 int s; 2967 2968#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2969 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2970 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2971 return; 2972 } 2973#endif 2974 2975 s = splvm(); 2976 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2977 2978 if (pv->pv_va >= eva || pv->pv_va < sva) { 2979 npv = TAILQ_NEXT(pv, pv_plist); 2980 continue; 2981 } 2982 2983#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2984 pte = vtopte(pv->pv_va); 2985#else 2986 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2987#endif 2988 tpte = *pte; 2989 2990 if (tpte == 0) { 2991 printf("TPTE at %p IS ZERO @ VA %08x\n", 2992 pte, pv->pv_va); 2993 panic("bad pte"); 2994 } 2995 2996/* 2997 * We cannot remove wired pages from a process' mapping at this time 2998 */ 2999 if (tpte & PG_W) { 3000 npv = TAILQ_NEXT(pv, pv_plist); 3001 continue; 3002 } 3003 3004 m = PHYS_TO_VM_PAGE(tpte); 3005 KASSERT(m->phys_addr == (tpte & PG_FRAME), 3006 ("vm_page_t %p phys_addr mismatch %08x %08x", 3007 m, m->phys_addr, tpte)); 3008 3009 KASSERT(m < &vm_page_array[vm_page_array_size], 3010 ("pmap_remove_pages: bad tpte %x", tpte)); 3011 3012 pv->pv_pmap->pm_stats.resident_count--; 3013 3014 *pte = 0; 3015 3016 /* 3017 * Update the vm_page_t clean and reference bits. 3018 */ 3019 if (tpte & PG_M) { 3020 vm_page_dirty(m); 3021 } 3022 3023 npv = TAILQ_NEXT(pv, pv_plist); 3024 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 3025 3026 m->md.pv_list_count--; 3027 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3028 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 3029 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 3030 } 3031 3032 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 3033 free_pv_entry(pv); 3034 } 3035 splx(s); 3036 pmap_invalidate_all(pmap); 3037} 3038 3039/* 3040 * pmap_testbit tests bits in pte's 3041 * note that the testbit/changebit routines are inline, 3042 * and a lot of things compile-time evaluate. 3043 */ 3044static boolean_t 3045pmap_testbit(m, bit) 3046 vm_page_t m; 3047 int bit; 3048{ 3049 pv_entry_t pv; 3050 pt_entry_t *pte; 3051 int s; 3052 3053 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3054 return FALSE; 3055 3056 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 3057 return FALSE; 3058 3059 s = splvm(); 3060 3061 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3062 /* 3063 * if the bit being tested is the modified bit, then 3064 * mark clean_map and ptes as never 3065 * modified. 3066 */ 3067 if (bit & (PG_A|PG_M)) { 3068 if (!pmap_track_modified(pv->pv_va)) 3069 continue; 3070 } 3071 3072#if defined(PMAP_DIAGNOSTIC) 3073 if (!pv->pv_pmap) { 3074 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3075 continue; 3076 } 3077#endif 3078 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3079 if (*pte & bit) { 3080 splx(s); 3081 return TRUE; 3082 } 3083 } 3084 splx(s); 3085 return (FALSE); 3086} 3087 3088/* 3089 * this routine is used to modify bits in ptes 3090 */ 3091static __inline void 3092pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3093{ 3094 register pv_entry_t pv; 3095 register pt_entry_t *pte; 3096 int s; 3097 3098 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3099 return; 3100 3101 s = splvm(); 3102 3103 /* 3104 * Loop over all current mappings setting/clearing as appropos If 3105 * setting RO do we need to clear the VAC? 3106 */ 3107 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3108 /* 3109 * don't write protect pager mappings 3110 */ 3111 if (!setem && (bit == PG_RW)) { 3112 if (!pmap_track_modified(pv->pv_va)) 3113 continue; 3114 } 3115 3116#if defined(PMAP_DIAGNOSTIC) 3117 if (!pv->pv_pmap) { 3118 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3119 continue; 3120 } 3121#endif 3122 3123 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3124 3125 if (setem) { 3126 *pte |= bit; 3127 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3128 } else { 3129 pt_entry_t pbits = *pte; 3130 if (pbits & bit) { 3131 if (bit == PG_RW) { 3132 if (pbits & PG_M) { 3133 vm_page_dirty(m); 3134 } 3135 *pte = pbits & ~(PG_M|PG_RW); 3136 } else { 3137 *pte = pbits & ~bit; 3138 } 3139 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3140 } 3141 } 3142 } 3143 splx(s); 3144} 3145 3146/* 3147 * pmap_page_protect: 3148 * 3149 * Lower the permission for all mappings to a given page. 3150 */ 3151void 3152pmap_page_protect(vm_page_t m, vm_prot_t prot) 3153{ 3154 if ((prot & VM_PROT_WRITE) == 0) { 3155 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3156 pmap_changebit(m, PG_RW, FALSE); 3157 } else { 3158 pmap_remove_all(m); 3159 } 3160 } 3161} 3162 3163vm_offset_t 3164pmap_phys_address(ppn) 3165 int ppn; 3166{ 3167 return (i386_ptob(ppn)); 3168} 3169 3170/* 3171 * pmap_ts_referenced: 3172 * 3173 * Return a count of reference bits for a page, clearing those bits. 3174 * It is not necessary for every reference bit to be cleared, but it 3175 * is necessary that 0 only be returned when there are truly no 3176 * reference bits set. 3177 * 3178 * XXX: The exact number of bits to check and clear is a matter that 3179 * should be tested and standardized at some point in the future for 3180 * optimal aging of shared pages. 3181 */ 3182int 3183pmap_ts_referenced(vm_page_t m) 3184{ 3185 register pv_entry_t pv, pvf, pvn; 3186 pt_entry_t *pte; 3187 int s; 3188 int rtval = 0; 3189 3190 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3191 return (rtval); 3192 3193 s = splvm(); 3194 3195 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3196 3197 pvf = pv; 3198 3199 do { 3200 pvn = TAILQ_NEXT(pv, pv_list); 3201 3202 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3203 3204 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3205 3206 if (!pmap_track_modified(pv->pv_va)) 3207 continue; 3208 3209 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3210 3211 if (pte && (*pte & PG_A)) { 3212 *pte &= ~PG_A; 3213 3214 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3215 3216 rtval++; 3217 if (rtval > 4) { 3218 break; 3219 } 3220 } 3221 } while ((pv = pvn) != NULL && pv != pvf); 3222 } 3223 splx(s); 3224 3225 return (rtval); 3226} 3227 3228/* 3229 * pmap_is_modified: 3230 * 3231 * Return whether or not the specified physical page was modified 3232 * in any physical maps. 3233 */ 3234boolean_t 3235pmap_is_modified(vm_page_t m) 3236{ 3237 return pmap_testbit(m, PG_M); 3238} 3239 3240/* 3241 * Clear the modify bits on the specified physical page. 3242 */ 3243void 3244pmap_clear_modify(vm_page_t m) 3245{ 3246 pmap_changebit(m, PG_M, FALSE); 3247} 3248 3249/* 3250 * pmap_clear_reference: 3251 * 3252 * Clear the reference bit on the specified physical page. 3253 */ 3254void 3255pmap_clear_reference(vm_page_t m) 3256{ 3257 pmap_changebit(m, PG_A, FALSE); 3258} 3259 3260/* 3261 * Miscellaneous support routines follow 3262 */ 3263 3264static void 3265i386_protection_init() 3266{ 3267 register int *kp, prot; 3268 3269 kp = protection_codes; 3270 for (prot = 0; prot < 8; prot++) { 3271 switch (prot) { 3272 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3273 /* 3274 * Read access is also 0. There isn't any execute bit, 3275 * so just make it readable. 3276 */ 3277 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3278 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3279 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3280 *kp++ = 0; 3281 break; 3282 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3283 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3284 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3285 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3286 *kp++ = PG_RW; 3287 break; 3288 } 3289 } 3290} 3291 3292/* 3293 * Map a set of physical memory pages into the kernel virtual 3294 * address space. Return a pointer to where it is mapped. This 3295 * routine is intended to be used for mapping device memory, 3296 * NOT real memory. 3297 */ 3298void * 3299pmap_mapdev(pa, size) 3300 vm_offset_t pa; 3301 vm_size_t size; 3302{ 3303 vm_offset_t va, tmpva, offset; 3304 pt_entry_t *pte; 3305 3306 offset = pa & PAGE_MASK; 3307 size = roundup(offset + size, PAGE_SIZE); 3308 3309 GIANT_REQUIRED; 3310 3311 va = kmem_alloc_pageable(kernel_map, size); 3312 if (!va) 3313 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3314 3315 pa = pa & PG_FRAME; 3316 for (tmpva = va; size > 0;) { 3317 pte = vtopte(tmpva); 3318 *pte = pa | PG_RW | PG_V | pgeflag; 3319 size -= PAGE_SIZE; 3320 tmpva += PAGE_SIZE; 3321 pa += PAGE_SIZE; 3322 } 3323 invltlb(); 3324 3325 return ((void *)(va + offset)); 3326} 3327 3328void 3329pmap_unmapdev(va, size) 3330 vm_offset_t va; 3331 vm_size_t size; 3332{ 3333 vm_offset_t base, offset; 3334 3335 base = va & PG_FRAME; 3336 offset = va & PAGE_MASK; 3337 size = roundup(offset + size, PAGE_SIZE); 3338 kmem_free(kernel_map, base, size); 3339} 3340 3341/* 3342 * perform the pmap work for mincore 3343 */ 3344int 3345pmap_mincore(pmap, addr) 3346 pmap_t pmap; 3347 vm_offset_t addr; 3348{ 3349 pt_entry_t *ptep, pte; 3350 vm_page_t m; 3351 int val = 0; 3352 3353 ptep = pmap_pte(pmap, addr); 3354 if (ptep == 0) { 3355 return 0; 3356 } 3357 3358 if ((pte = *ptep) != 0) { 3359 vm_offset_t pa; 3360 3361 val = MINCORE_INCORE; 3362 if ((pte & PG_MANAGED) == 0) 3363 return val; 3364 3365 pa = pte & PG_FRAME; 3366 3367 m = PHYS_TO_VM_PAGE(pa); 3368 3369 /* 3370 * Modified by us 3371 */ 3372 if (pte & PG_M) 3373 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3374 /* 3375 * Modified by someone 3376 */ 3377 else if (m->dirty || pmap_is_modified(m)) 3378 val |= MINCORE_MODIFIED_OTHER; 3379 /* 3380 * Referenced by us 3381 */ 3382 if (pte & PG_A) 3383 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3384 3385 /* 3386 * Referenced by someone 3387 */ 3388 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3389 val |= MINCORE_REFERENCED_OTHER; 3390 vm_page_flag_set(m, PG_REFERENCED); 3391 } 3392 } 3393 return val; 3394} 3395 3396void 3397pmap_activate(struct thread *td) 3398{ 3399 struct proc *p = td->td_proc; 3400 pmap_t pmap; 3401 u_int32_t cr3; 3402 3403 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3404#if defined(SMP) 3405 pmap->pm_active |= PCPU_GET(cpumask); 3406#else 3407 pmap->pm_active |= 1; 3408#endif 3409#if defined(SWTCH_OPTIM_STATS) 3410 tlb_flush_count++; 3411#endif 3412 cr3 = vtophys(pmap->pm_pdir); 3413 /* XXXKSE this is wrong. 3414 * pmap_activate is for the current thread on the current cpu 3415 */ 3416 if (p->p_flag & P_KSES) { 3417 /* Make sure all other cr3 entries are updated. */ 3418 /* what if they are running? XXXKSE (maybe abort them) */ 3419 FOREACH_THREAD_IN_PROC(p, td) { 3420 td->td_pcb->pcb_cr3 = cr3; 3421 } 3422 } else { 3423 td->td_pcb->pcb_cr3 = cr3; 3424 } 3425 load_cr3(cr3); 3426} 3427 3428vm_offset_t 3429pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3430{ 3431 3432 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3433 return addr; 3434 } 3435 3436 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3437 return addr; 3438} 3439 3440 3441#if defined(PMAP_DEBUG) 3442pmap_pid_dump(int pid) 3443{ 3444 pmap_t pmap; 3445 struct proc *p; 3446 int npte = 0; 3447 int index; 3448 3449 sx_slock(&allproc_lock); 3450 LIST_FOREACH(p, &allproc, p_list) { 3451 if (p->p_pid != pid) 3452 continue; 3453 3454 if (p->p_vmspace) { 3455 int i,j; 3456 index = 0; 3457 pmap = vmspace_pmap(p->p_vmspace); 3458 for (i = 0; i < NPDEPG; i++) { 3459 pd_entry_t *pde; 3460 pt_entry_t *pte; 3461 vm_offset_t base = i << PDRSHIFT; 3462 3463 pde = &pmap->pm_pdir[i]; 3464 if (pde && pmap_pde_v(pde)) { 3465 for (j = 0; j < NPTEPG; j++) { 3466 vm_offset_t va = base + (j << PAGE_SHIFT); 3467 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3468 if (index) { 3469 index = 0; 3470 printf("\n"); 3471 } 3472 sx_sunlock(&allproc_lock); 3473 return npte; 3474 } 3475 pte = pmap_pte_quick(pmap, va); 3476 if (pte && pmap_pte_v(pte)) { 3477 pt_entry_t pa; 3478 vm_page_t m; 3479 pa = *pte; 3480 m = PHYS_TO_VM_PAGE(pa); 3481 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3482 va, pa, m->hold_count, m->wire_count, m->flags); 3483 npte++; 3484 index++; 3485 if (index >= 2) { 3486 index = 0; 3487 printf("\n"); 3488 } else { 3489 printf(" "); 3490 } 3491 } 3492 } 3493 } 3494 } 3495 } 3496 } 3497 sx_sunlock(&allproc_lock); 3498 return npte; 3499} 3500#endif 3501 3502#if defined(DEBUG) 3503 3504static void pads(pmap_t pm); 3505void pmap_pvdump(vm_offset_t pa); 3506 3507/* print address space of pmap*/ 3508static void 3509pads(pm) 3510 pmap_t pm; 3511{ 3512 int i, j; 3513 vm_offset_t va; 3514 pt_entry_t *ptep; 3515 3516 if (pm == kernel_pmap) 3517 return; 3518 for (i = 0; i < NPDEPG; i++) 3519 if (pm->pm_pdir[i]) 3520 for (j = 0; j < NPTEPG; j++) { 3521 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3522 if (pm == kernel_pmap && va < KERNBASE) 3523 continue; 3524 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3525 continue; 3526 ptep = pmap_pte_quick(pm, va); 3527 if (pmap_pte_v(ptep)) 3528 printf("%x:%x ", va, *ptep); 3529 }; 3530 3531} 3532 3533void 3534pmap_pvdump(pa) 3535 vm_offset_t pa; 3536{ 3537 pv_entry_t pv; 3538 vm_page_t m; 3539 3540 printf("pa %x", pa); 3541 m = PHYS_TO_VM_PAGE(pa); 3542 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3543 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3544 pads(pv->pv_pmap); 3545 } 3546 printf(" "); 3547} 3548#endif 3549