pmap.c revision 106753
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 106753 2002-11-11 05:17:34Z alc $ 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_pmap.h" 72#include "opt_msgbuf.h" 73#include "opt_kstack_pages.h" 74 75#include <sys/param.h> 76#include <sys/systm.h> 77#include <sys/kernel.h> 78#include <sys/lock.h> 79#include <sys/mman.h> 80#include <sys/msgbuf.h> 81#include <sys/mutex.h> 82#include <sys/proc.h> 83#include <sys/sx.h> 84#include <sys/user.h> 85#include <sys/vmmeter.h> 86#include <sys/sysctl.h> 87#ifdef SMP 88#include <sys/smp.h> 89#endif 90 91#include <vm/vm.h> 92#include <vm/vm_param.h> 93#include <vm/vm_kern.h> 94#include <vm/vm_page.h> 95#include <vm/vm_map.h> 96#include <vm/vm_object.h> 97#include <vm/vm_extern.h> 98#include <vm/vm_pageout.h> 99#include <vm/vm_pager.h> 100#include <vm/uma.h> 101 102#include <machine/cpu.h> 103#include <machine/cputypes.h> 104#include <machine/md_var.h> 105#include <machine/specialreg.h> 106#if defined(SMP) || defined(APIC_IO) 107#include <machine/smp.h> 108#include <machine/apic.h> 109#include <machine/segments.h> 110#include <machine/tss.h> 111#endif /* SMP || APIC_IO */ 112 113#define PMAP_KEEP_PDIRS 114#ifndef PMAP_SHPGPERPROC 115#define PMAP_SHPGPERPROC 200 116#endif 117 118#if defined(DIAGNOSTIC) 119#define PMAP_DIAGNOSTIC 120#endif 121 122#define MINPV 2048 123 124#if !defined(PMAP_DIAGNOSTIC) 125#define PMAP_INLINE __inline 126#else 127#define PMAP_INLINE 128#endif 129 130/* 131 * Get PDEs and PTEs for user/kernel address space 132 */ 133#define pmap_pde(m, v) (&((m)->pm_pdir[(vm_offset_t)(v) >> PDRSHIFT])) 134#define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT]) 135 136#define pmap_pde_v(pte) ((*(int *)pte & PG_V) != 0) 137#define pmap_pte_w(pte) ((*(int *)pte & PG_W) != 0) 138#define pmap_pte_m(pte) ((*(int *)pte & PG_M) != 0) 139#define pmap_pte_u(pte) ((*(int *)pte & PG_A) != 0) 140#define pmap_pte_v(pte) ((*(int *)pte & PG_V) != 0) 141 142#define pmap_pte_set_w(pte, v) ((v)?(*(int *)pte |= PG_W):(*(int *)pte &= ~PG_W)) 143#define pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v))) 144 145/* 146 * Given a map and a machine independent protection code, 147 * convert to a vax protection code. 148 */ 149#define pte_prot(m, p) (protection_codes[p]) 150static int protection_codes[8]; 151 152struct pmap kernel_pmap_store; 153LIST_HEAD(pmaplist, pmap); 154struct pmaplist allpmaps; 155 156vm_offset_t avail_start; /* PA of first available physical page */ 157vm_offset_t avail_end; /* PA of last available physical page */ 158vm_offset_t virtual_avail; /* VA of first avail page (after kernel bss) */ 159vm_offset_t virtual_end; /* VA of last avail page (end of kernel AS) */ 160static boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */ 161static int pgeflag; /* PG_G or-in */ 162static int pseflag; /* PG_PS or-in */ 163 164static vm_object_t kptobj; 165 166static int nkpt; 167vm_offset_t kernel_vm_end; 168extern u_int32_t KERNend; 169 170/* 171 * Data for the pv entry allocation mechanism 172 */ 173static uma_zone_t pvzone; 174static struct vm_object pvzone_obj; 175static int pv_entry_count = 0, pv_entry_max = 0, pv_entry_high_water = 0; 176static int pmap_pagedaemon_waken = 0; 177 178/* 179 * All those kernel PT submaps that BSD is so fond of 180 */ 181pt_entry_t *CMAP1 = 0; 182static pt_entry_t *CMAP2, *CMAP3, *ptmmap; 183caddr_t CADDR1 = 0, ptvmmap = 0; 184static caddr_t CADDR2, CADDR3; 185static pt_entry_t *msgbufmap; 186struct msgbuf *msgbufp = 0; 187 188/* 189 * Crashdump maps. 190 */ 191static pt_entry_t *pt_crashdumpmap; 192static caddr_t crashdumpmap; 193 194#ifdef SMP 195extern pt_entry_t *SMPpt; 196#endif 197static pt_entry_t *PMAP1 = 0; 198static pt_entry_t *PADDR1 = 0; 199 200static PMAP_INLINE void free_pv_entry(pv_entry_t pv); 201static pt_entry_t *get_ptbase(pmap_t pmap); 202static pv_entry_t get_pv_entry(void); 203static void i386_protection_init(void); 204static __inline void pmap_changebit(vm_page_t m, int bit, boolean_t setem); 205 206static vm_page_t pmap_enter_quick(pmap_t pmap, vm_offset_t va, 207 vm_page_t m, vm_page_t mpte); 208static int pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t sva); 209static void pmap_remove_page(struct pmap *pmap, vm_offset_t va); 210static int pmap_remove_entry(struct pmap *pmap, vm_page_t m, 211 vm_offset_t va); 212static boolean_t pmap_testbit(vm_page_t m, int bit); 213static void pmap_insert_entry(pmap_t pmap, vm_offset_t va, 214 vm_page_t mpte, vm_page_t m); 215 216static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va); 217 218static int pmap_release_free_page(pmap_t pmap, vm_page_t p); 219static vm_page_t _pmap_allocpte(pmap_t pmap, unsigned ptepindex); 220static pt_entry_t *pmap_pte_quick(pmap_t pmap, vm_offset_t va); 221static vm_page_t pmap_page_lookup(vm_object_t object, vm_pindex_t pindex); 222static int pmap_unuse_pt(pmap_t, vm_offset_t, vm_page_t); 223static vm_offset_t pmap_kmem_choose(vm_offset_t addr); 224static void *pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait); 225 226static pd_entry_t pdir4mb; 227 228/* 229 * Routine: pmap_pte 230 * Function: 231 * Extract the page table entry associated 232 * with the given map/virtual_address pair. 233 */ 234 235PMAP_INLINE pt_entry_t * 236pmap_pte(pmap, va) 237 register pmap_t pmap; 238 vm_offset_t va; 239{ 240 pd_entry_t *pdeaddr; 241 242 if (pmap) { 243 pdeaddr = pmap_pde(pmap, va); 244 if (*pdeaddr & PG_PS) 245 return pdeaddr; 246 if (*pdeaddr) { 247 return get_ptbase(pmap) + i386_btop(va); 248 } 249 } 250 return (0); 251} 252 253/* 254 * Move the kernel virtual free pointer to the next 255 * 4MB. This is used to help improve performance 256 * by using a large (4MB) page for much of the kernel 257 * (.text, .data, .bss) 258 */ 259static vm_offset_t 260pmap_kmem_choose(vm_offset_t addr) 261{ 262 vm_offset_t newaddr = addr; 263 264#ifndef DISABLE_PSE 265 if (cpu_feature & CPUID_PSE) 266 newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 267#endif 268 return newaddr; 269} 270 271/* 272 * Bootstrap the system enough to run with virtual memory. 273 * 274 * On the i386 this is called after mapping has already been enabled 275 * and just syncs the pmap module with what has already been done. 276 * [We can't call it easily with mapping off since the kernel is not 277 * mapped with PA == VA, hence we would have to relocate every address 278 * from the linked base (virtual) address "KERNBASE" to the actual 279 * (physical) address starting relative to 0] 280 */ 281void 282pmap_bootstrap(firstaddr, loadaddr) 283 vm_offset_t firstaddr; 284 vm_offset_t loadaddr; 285{ 286 vm_offset_t va; 287 pt_entry_t *pte; 288 int i; 289 290 avail_start = firstaddr; 291 292 /* 293 * XXX The calculation of virtual_avail is wrong. It's NKPT*PAGE_SIZE too 294 * large. It should instead be correctly calculated in locore.s and 295 * not based on 'first' (which is a physical address, not a virtual 296 * address, for the start of unused physical memory). The kernel 297 * page tables are NOT double mapped and thus should not be included 298 * in this calculation. 299 */ 300 virtual_avail = (vm_offset_t) KERNBASE + firstaddr; 301 virtual_avail = pmap_kmem_choose(virtual_avail); 302 303 virtual_end = VM_MAX_KERNEL_ADDRESS; 304 305 /* 306 * Initialize protection array. 307 */ 308 i386_protection_init(); 309 310 /* 311 * Initialize the kernel pmap (which is statically allocated). 312 */ 313 kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD); 314 kernel_pmap->pm_active = -1; /* don't allow deactivation */ 315 TAILQ_INIT(&kernel_pmap->pm_pvlist); 316 LIST_INIT(&allpmaps); 317 LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list); 318 nkpt = NKPT; 319 320 /* 321 * Reserve some special page table entries/VA space for temporary 322 * mapping of pages. 323 */ 324#define SYSMAP(c, p, v, n) \ 325 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n); 326 327 va = virtual_avail; 328 pte = (pt_entry_t *) pmap_pte(kernel_pmap, va); 329 330 /* 331 * CMAP1/CMAP2 are used for zeroing and copying pages. 332 * CMAP3 is used for the idle process page zeroing. 333 */ 334 SYSMAP(caddr_t, CMAP1, CADDR1, 1) 335 SYSMAP(caddr_t, CMAP2, CADDR2, 1) 336 SYSMAP(caddr_t, CMAP3, CADDR3, 1) 337 338 /* 339 * Crashdump maps. 340 */ 341 SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS); 342 343 /* 344 * ptvmmap is used for reading arbitrary physical pages via /dev/mem. 345 * XXX ptmmap is not used. 346 */ 347 SYSMAP(caddr_t, ptmmap, ptvmmap, 1) 348 349 /* 350 * msgbufp is used to map the system message buffer. 351 * XXX msgbufmap is not used. 352 */ 353 SYSMAP(struct msgbuf *, msgbufmap, msgbufp, 354 atop(round_page(MSGBUF_SIZE))) 355 356 /* 357 * ptemap is used for pmap_pte_quick 358 */ 359 SYSMAP(pt_entry_t *, PMAP1, PADDR1, 1); 360 361 virtual_avail = va; 362 363 *CMAP1 = *CMAP2 = 0; 364 for (i = 0; i < NKPT; i++) 365 PTD[i] = 0; 366 367 pgeflag = 0; 368#ifndef DISABLE_PG_G 369 if (cpu_feature & CPUID_PGE) 370 pgeflag = PG_G; 371#endif 372 373/* 374 * Initialize the 4MB page size flag 375 */ 376 pseflag = 0; 377/* 378 * The 4MB page version of the initial 379 * kernel page mapping. 380 */ 381 pdir4mb = 0; 382 383#ifndef DISABLE_PSE 384 if (cpu_feature & CPUID_PSE) { 385 pd_entry_t ptditmp; 386 /* 387 * Note that we have enabled PSE mode 388 */ 389 pseflag = PG_PS; 390 ptditmp = *(PTmap + i386_btop(KERNBASE)); 391 ptditmp &= ~(NBPDR - 1); 392 ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag; 393 pdir4mb = ptditmp; 394 } 395#endif 396#ifndef SMP 397 /* 398 * Turn on PGE/PSE. SMP does this later on since the 399 * 4K page tables are required for AP boot (for now). 400 * XXX fixme. 401 */ 402 pmap_set_opt(); 403#endif 404#ifdef SMP 405 if (cpu_apic_address == 0) 406 panic("pmap_bootstrap: no local apic! (non-SMP hardware?)"); 407 408 /* local apic is mapped on last page */ 409 SMPpt[NPTEPG - 1] = (pt_entry_t)(PG_V | PG_RW | PG_N | pgeflag | 410 (cpu_apic_address & PG_FRAME)); 411#endif 412 invltlb(); 413} 414 415/* 416 * Enable 4MB page mode for MP startup. Turn on PG_G support. 417 * BSP will run this after all the AP's have started up. 418 */ 419void 420pmap_set_opt(void) 421{ 422 pt_entry_t *pte; 423 vm_offset_t va, endva; 424 425 if (pgeflag && (cpu_feature & CPUID_PGE)) { 426 load_cr4(rcr4() | CR4_PGE); 427 invltlb(); /* Insurance */ 428 } 429#ifndef DISABLE_PSE 430 if (pseflag && (cpu_feature & CPUID_PSE)) { 431 load_cr4(rcr4() | CR4_PSE); 432 invltlb(); /* Insurance */ 433 } 434#endif 435 if (PCPU_GET(cpuid) == 0) { 436#ifndef DISABLE_PSE 437 if (pdir4mb) { 438 kernel_pmap->pm_pdir[KPTDI] = PTD[KPTDI] = pdir4mb; 439 invltlb(); /* Insurance */ 440 } 441#endif 442 if (pgeflag) { 443 /* Turn on PG_G for text, data, bss pages. */ 444 va = (vm_offset_t)btext; 445#ifndef DISABLE_PSE 446 if (pseflag && (cpu_feature & CPUID_PSE)) { 447 if (va < KERNBASE + (1 << PDRSHIFT)) 448 va = KERNBASE + (1 << PDRSHIFT); 449 } 450#endif 451 endva = KERNBASE + KERNend; 452 while (va < endva) { 453 pte = vtopte(va); 454 if (*pte) 455 *pte |= pgeflag; 456 va += PAGE_SIZE; 457 } 458 invltlb(); /* Insurance */ 459 } 460 /* 461 * We do not need to broadcast the invltlb here, because 462 * each AP does it the moment it is released from the boot 463 * lock. See ap_init(). 464 */ 465 } 466} 467 468static void * 469pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait) 470{ 471 *flags = UMA_SLAB_PRIV; 472 return (void *)kmem_alloc(kernel_map, bytes); 473} 474 475/* 476 * Initialize the pmap module. 477 * Called by vm_init, to initialize any structures that the pmap 478 * system needs to map virtual memory. 479 * pmap_init has been enhanced to support in a fairly consistant 480 * way, discontiguous physical memory. 481 */ 482void 483pmap_init(phys_start, phys_end) 484 vm_offset_t phys_start, phys_end; 485{ 486 int i; 487 int initial_pvs; 488 489 /* 490 * object for kernel page table pages 491 */ 492 kptobj = vm_object_allocate(OBJT_DEFAULT, NKPDE); 493 494 /* 495 * Allocate memory for random pmap data structures. Includes the 496 * pv_head_table. 497 */ 498 499 for(i = 0; i < vm_page_array_size; i++) { 500 vm_page_t m; 501 502 m = &vm_page_array[i]; 503 TAILQ_INIT(&m->md.pv_list); 504 m->md.pv_list_count = 0; 505 } 506 507 /* 508 * init the pv free list 509 */ 510 initial_pvs = vm_page_array_size; 511 if (initial_pvs < MINPV) 512 initial_pvs = MINPV; 513 pvzone = uma_zcreate("PV ENTRY", sizeof (struct pv_entry), NULL, NULL, 514 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM); 515 uma_zone_set_allocf(pvzone, pmap_allocf); 516 uma_prealloc(pvzone, initial_pvs); 517 518 /* 519 * Now it is safe to enable pv_table recording. 520 */ 521 pmap_initialized = TRUE; 522} 523 524/* 525 * Initialize the address space (zone) for the pv_entries. Set a 526 * high water mark so that the system can recover from excessive 527 * numbers of pv entries. 528 */ 529void 530pmap_init2() 531{ 532 int shpgperproc = PMAP_SHPGPERPROC; 533 534 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc); 535 pv_entry_max = shpgperproc * maxproc + vm_page_array_size; 536 TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max); 537 pv_entry_high_water = 9 * (pv_entry_max / 10); 538 uma_zone_set_obj(pvzone, &pvzone_obj, pv_entry_max); 539} 540 541 542/*************************************************** 543 * Low level helper routines..... 544 ***************************************************/ 545 546#if defined(PMAP_DIAGNOSTIC) 547 548/* 549 * This code checks for non-writeable/modified pages. 550 * This should be an invalid condition. 551 */ 552static int 553pmap_nw_modified(pt_entry_t ptea) 554{ 555 int pte; 556 557 pte = (int) ptea; 558 559 if ((pte & (PG_M|PG_RW)) == PG_M) 560 return 1; 561 else 562 return 0; 563} 564#endif 565 566 567/* 568 * this routine defines the region(s) of memory that should 569 * not be tested for the modified bit. 570 */ 571static PMAP_INLINE int 572pmap_track_modified(vm_offset_t va) 573{ 574 if ((va < kmi.clean_sva) || (va >= kmi.clean_eva)) 575 return 1; 576 else 577 return 0; 578} 579 580#ifdef I386_CPU 581/* 582 * i386 only has "invalidate everything" and no SMP to worry about. 583 */ 584PMAP_INLINE void 585pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 586{ 587 588 if (pmap == kernel_pmap || pmap->pm_active) 589 invltlb(); 590} 591 592PMAP_INLINE void 593pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 594{ 595 596 if (pmap == kernel_pmap || pmap->pm_active) 597 invltlb(); 598} 599 600PMAP_INLINE void 601pmap_invalidate_all(pmap_t pmap) 602{ 603 604 if (pmap == kernel_pmap || pmap->pm_active) 605 invltlb(); 606} 607#else /* !I386_CPU */ 608#ifdef SMP 609/* 610 * For SMP, these functions have to use the IPI mechanism for coherence. 611 */ 612void 613pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 614{ 615 u_int cpumask; 616 u_int other_cpus; 617 618 critical_enter(); 619 /* 620 * We need to disable interrupt preemption but MUST NOT have 621 * interrupts disabled here. 622 * XXX we may need to hold schedlock to get a coherent pm_active 623 */ 624 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 625 invlpg(va); 626 smp_invlpg(va); 627 } else { 628 cpumask = PCPU_GET(cpumask); 629 other_cpus = PCPU_GET(other_cpus); 630 if (pmap->pm_active & cpumask) 631 invlpg(va); 632 if (pmap->pm_active & other_cpus) 633 smp_masked_invlpg(pmap->pm_active & other_cpus, va); 634 } 635 critical_exit(); 636} 637 638void 639pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 640{ 641 u_int cpumask; 642 u_int other_cpus; 643 vm_offset_t addr; 644 645 critical_enter(); 646 /* 647 * We need to disable interrupt preemption but MUST NOT have 648 * interrupts disabled here. 649 * XXX we may need to hold schedlock to get a coherent pm_active 650 */ 651 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 652 for (addr = sva; addr < eva; addr += PAGE_SIZE) 653 invlpg(addr); 654 smp_invlpg_range(sva, eva); 655 } else { 656 cpumask = PCPU_GET(cpumask); 657 other_cpus = PCPU_GET(other_cpus); 658 if (pmap->pm_active & cpumask) 659 for (addr = sva; addr < eva; addr += PAGE_SIZE) 660 invlpg(addr); 661 if (pmap->pm_active & other_cpus) 662 smp_masked_invlpg_range(pmap->pm_active & other_cpus, 663 sva, eva); 664 } 665 critical_exit(); 666} 667 668void 669pmap_invalidate_all(pmap_t pmap) 670{ 671 u_int cpumask; 672 u_int other_cpus; 673 674#ifdef SWTCH_OPTIM_STATS 675 tlb_flush_count++; 676#endif 677 critical_enter(); 678 /* 679 * We need to disable interrupt preemption but MUST NOT have 680 * interrupts disabled here. 681 * XXX we may need to hold schedlock to get a coherent pm_active 682 */ 683 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 684 invltlb(); 685 smp_invltlb(); 686 } else { 687 cpumask = PCPU_GET(cpumask); 688 other_cpus = PCPU_GET(other_cpus); 689 if (pmap->pm_active & cpumask) 690 invltlb(); 691 if (pmap->pm_active & other_cpus) 692 smp_masked_invltlb(pmap->pm_active & other_cpus); 693 } 694 critical_exit(); 695} 696#else /* !SMP */ 697/* 698 * Normal, non-SMP, 486+ invalidation functions. 699 * We inline these within pmap.c for speed. 700 */ 701PMAP_INLINE void 702pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 703{ 704 705 if (pmap == kernel_pmap || pmap->pm_active) 706 invlpg(va); 707} 708 709PMAP_INLINE void 710pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 711{ 712 vm_offset_t addr; 713 714 if (pmap == kernel_pmap || pmap->pm_active) 715 for (addr = sva; addr < eva; addr += PAGE_SIZE) 716 invlpg(addr); 717} 718 719PMAP_INLINE void 720pmap_invalidate_all(pmap_t pmap) 721{ 722 723 if (pmap == kernel_pmap || pmap->pm_active) 724 invltlb(); 725} 726#endif /* !SMP */ 727#endif /* !I386_CPU */ 728 729/* 730 * Return an address which is the base of the Virtual mapping of 731 * all the PTEs for the given pmap. Note this doesn't say that 732 * all the PTEs will be present or that the pages there are valid. 733 * The PTEs are made available by the recursive mapping trick. 734 * It will map in the alternate PTE space if needed. 735 */ 736static pt_entry_t * 737get_ptbase(pmap) 738 pmap_t pmap; 739{ 740 pd_entry_t frame; 741 742 /* are we current address space or kernel? */ 743 if (pmap == kernel_pmap) 744 return PTmap; 745 frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 746 if (frame == (PTDpde & PG_FRAME)) 747 return PTmap; 748 /* otherwise, we are alternate address space */ 749 if (frame != (APTDpde & PG_FRAME)) { 750 APTDpde = (pd_entry_t) (frame | PG_RW | PG_V); 751 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 752 } 753 return APTmap; 754} 755 756/* 757 * Super fast pmap_pte routine best used when scanning 758 * the pv lists. This eliminates many coarse-grained 759 * invltlb calls. Note that many of the pv list 760 * scans are across different pmaps. It is very wasteful 761 * to do an entire invltlb for checking a single mapping. 762 */ 763 764static pt_entry_t * 765pmap_pte_quick(pmap, va) 766 register pmap_t pmap; 767 vm_offset_t va; 768{ 769 pd_entry_t pde, newpf; 770 pde = pmap->pm_pdir[va >> PDRSHIFT]; 771 if (pde != 0) { 772 pd_entry_t frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 773 unsigned index = i386_btop(va); 774 /* are we current address space or kernel? */ 775 if (pmap == kernel_pmap || frame == (PTDpde & PG_FRAME)) 776 return PTmap + index; 777 newpf = pde & PG_FRAME; 778 if (((*PMAP1) & PG_FRAME) != newpf) { 779 *PMAP1 = newpf | PG_RW | PG_V; 780 pmap_invalidate_page(kernel_pmap, (vm_offset_t)PADDR1); 781 } 782 return PADDR1 + (index & (NPTEPG - 1)); 783 } 784 return (0); 785} 786 787/* 788 * Routine: pmap_extract 789 * Function: 790 * Extract the physical page address associated 791 * with the given map/virtual_address pair. 792 */ 793vm_offset_t 794pmap_extract(pmap, va) 795 register pmap_t pmap; 796 vm_offset_t va; 797{ 798 vm_offset_t rtval; /* XXX FIXME */ 799 vm_offset_t pdirindex; 800 801 if (pmap == 0) 802 return 0; 803 pdirindex = va >> PDRSHIFT; 804 rtval = pmap->pm_pdir[pdirindex]; 805 if (rtval != 0) { 806 pt_entry_t *pte; 807 if ((rtval & PG_PS) != 0) { 808 rtval &= ~(NBPDR - 1); 809 rtval |= va & (NBPDR - 1); 810 return rtval; 811 } 812 pte = get_ptbase(pmap) + i386_btop(va); 813 rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); 814 return rtval; 815 } 816 return 0; 817 818} 819 820/*************************************************** 821 * Low level mapping routines..... 822 ***************************************************/ 823 824/* 825 * Add a wired page to the kva. 826 * Note: not SMP coherent. 827 */ 828PMAP_INLINE void 829pmap_kenter(vm_offset_t va, vm_offset_t pa) 830{ 831 pt_entry_t *pte; 832 833 pte = vtopte(va); 834 *pte = pa | PG_RW | PG_V | pgeflag; 835} 836 837/* 838 * Remove a page from the kernel pagetables. 839 * Note: not SMP coherent. 840 */ 841PMAP_INLINE void 842pmap_kremove(vm_offset_t va) 843{ 844 pt_entry_t *pte; 845 846 pte = vtopte(va); 847 *pte = 0; 848} 849 850/* 851 * Used to map a range of physical addresses into kernel 852 * virtual address space. 853 * 854 * The value passed in '*virt' is a suggested virtual address for 855 * the mapping. Architectures which can support a direct-mapped 856 * physical to virtual region can return the appropriate address 857 * within that region, leaving '*virt' unchanged. Other 858 * architectures should map the pages starting at '*virt' and 859 * update '*virt' with the first usable address after the mapped 860 * region. 861 */ 862vm_offset_t 863pmap_map(vm_offset_t *virt, vm_offset_t start, vm_offset_t end, int prot) 864{ 865 vm_offset_t va, sva; 866 867 va = sva = *virt; 868 while (start < end) { 869 pmap_kenter(va, start); 870 va += PAGE_SIZE; 871 start += PAGE_SIZE; 872 } 873 pmap_invalidate_range(kernel_pmap, sva, va); 874 *virt = va; 875 return (sva); 876} 877 878 879/* 880 * Add a list of wired pages to the kva 881 * this routine is only used for temporary 882 * kernel mappings that do not need to have 883 * page modification or references recorded. 884 * Note that old mappings are simply written 885 * over. The page *must* be wired. 886 * Note: SMP coherent. Uses a ranged shootdown IPI. 887 */ 888void 889pmap_qenter(vm_offset_t sva, vm_page_t *m, int count) 890{ 891 vm_offset_t va; 892 893 va = sva; 894 while (count-- > 0) { 895 pmap_kenter(va, VM_PAGE_TO_PHYS(*m)); 896 va += PAGE_SIZE; 897 m++; 898 } 899 pmap_invalidate_range(kernel_pmap, sva, va); 900} 901 902/* 903 * This routine tears out page mappings from the 904 * kernel -- it is meant only for temporary mappings. 905 * Note: SMP coherent. Uses a ranged shootdown IPI. 906 */ 907void 908pmap_qremove(vm_offset_t sva, int count) 909{ 910 vm_offset_t va; 911 912 va = sva; 913 while (count-- > 0) { 914 pmap_kremove(va); 915 va += PAGE_SIZE; 916 } 917 pmap_invalidate_range(kernel_pmap, sva, va); 918} 919 920static vm_page_t 921pmap_page_lookup(vm_object_t object, vm_pindex_t pindex) 922{ 923 vm_page_t m; 924 925retry: 926 m = vm_page_lookup(object, pindex); 927 if (m != NULL) { 928 vm_page_lock_queues(); 929 if (vm_page_sleep_if_busy(m, FALSE, "pplookp")) 930 goto retry; 931 vm_page_unlock_queues(); 932 } 933 return m; 934} 935 936#ifndef KSTACK_MAX_PAGES 937#define KSTACK_MAX_PAGES 32 938#endif 939 940/* 941 * Create the kernel stack (including pcb for i386) for a new thread. 942 * This routine directly affects the fork perf for a process and 943 * create performance for a thread. 944 */ 945void 946pmap_new_thread(struct thread *td, int pages) 947{ 948 int i; 949 vm_page_t ma[KSTACK_MAX_PAGES]; 950 vm_object_t ksobj; 951 vm_page_t m; 952 vm_offset_t ks; 953 954 /* Bounds check */ 955 if (pages <= 1) 956 pages = KSTACK_PAGES; 957 else if (pages > KSTACK_MAX_PAGES) 958 pages = KSTACK_MAX_PAGES; 959 960 /* 961 * allocate object for the kstack 962 */ 963 ksobj = vm_object_allocate(OBJT_DEFAULT, pages); 964 td->td_kstack_obj = ksobj; 965 966 /* get a kernel virtual address for the kstack for this thread */ 967#ifdef KSTACK_GUARD 968 ks = kmem_alloc_nofault(kernel_map, (pages + 1) * PAGE_SIZE); 969 if (ks == 0) 970 panic("pmap_new_thread: kstack allocation failed"); 971 if (*vtopte(ks) != 0) 972 pmap_qremove(ks, 1); 973 ks += PAGE_SIZE; 974 td->td_kstack = ks; 975#else 976 /* get a kernel virtual address for the kstack for this thread */ 977 ks = kmem_alloc_nofault(kernel_map, pages * PAGE_SIZE); 978 if (ks == 0) 979 panic("pmap_new_thread: kstack allocation failed"); 980 td->td_kstack = ks; 981#endif 982 /* 983 * Knowing the number of pages allocated is useful when you 984 * want to deallocate them. 985 */ 986 td->td_kstack_pages = pages; 987 988 /* 989 * For the length of the stack, link in a real page of ram for each 990 * page of stack. 991 */ 992 for (i = 0; i < pages; i++) { 993 /* 994 * Get a kernel stack page 995 */ 996 m = vm_page_grab(ksobj, i, 997 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED); 998 ma[i] = m; 999 1000 vm_page_wakeup(m); 1001 vm_page_flag_clear(m, PG_ZERO); 1002 m->valid = VM_PAGE_BITS_ALL; 1003 } 1004 pmap_qenter(ks, ma, pages); 1005} 1006 1007/* 1008 * Dispose the kernel stack for a thread that has exited. 1009 * This routine directly impacts the exit perf of a process and thread. 1010 */ 1011void 1012pmap_dispose_thread(td) 1013 struct thread *td; 1014{ 1015 int i; 1016 int pages; 1017 vm_object_t ksobj; 1018 vm_offset_t ks; 1019 vm_page_t m; 1020 1021 pages = td->td_kstack_pages; 1022 ksobj = td->td_kstack_obj; 1023 ks = td->td_kstack; 1024 pmap_qremove(ks, pages); 1025 for (i = 0; i < pages; i++) { 1026 m = vm_page_lookup(ksobj, i); 1027 if (m == NULL) 1028 panic("pmap_dispose_thread: kstack already missing?"); 1029 vm_page_lock_queues(); 1030 vm_page_busy(m); 1031 vm_page_unwire(m, 0); 1032 vm_page_free(m); 1033 vm_page_unlock_queues(); 1034 } 1035 /* 1036 * Free the space that this stack was mapped to in the kernel 1037 * address map. 1038 */ 1039#ifdef KSTACK_GUARD 1040 kmem_free(kernel_map, ks - PAGE_SIZE, (pages + 1) * PAGE_SIZE); 1041#else 1042 kmem_free(kernel_map, ks, pages * PAGE_SIZE); 1043#endif 1044 vm_object_deallocate(ksobj); 1045} 1046 1047/* 1048 * Set up a variable sized alternate kstack. Though it may look MI, it may 1049 * need to be different on certain arches like ia64. 1050 */ 1051void 1052pmap_new_altkstack(struct thread *td, int pages) 1053{ 1054 /* shuffle the original stack */ 1055 td->td_altkstack_obj = td->td_kstack_obj; 1056 td->td_altkstack = td->td_kstack; 1057 td->td_altkstack_pages = td->td_kstack_pages; 1058 1059 pmap_new_thread(td, pages); 1060} 1061 1062void 1063pmap_dispose_altkstack(td) 1064 struct thread *td; 1065{ 1066 pmap_dispose_thread(td); 1067 1068 /* restore the original kstack */ 1069 td->td_kstack = td->td_altkstack; 1070 td->td_kstack_obj = td->td_altkstack_obj; 1071 td->td_kstack_pages = td->td_altkstack_pages; 1072 td->td_altkstack = 0; 1073 td->td_altkstack_obj = NULL; 1074 td->td_altkstack_pages = 0; 1075} 1076 1077/* 1078 * Allow the Kernel stack for a thread to be prejudicially paged out. 1079 */ 1080void 1081pmap_swapout_thread(td) 1082 struct thread *td; 1083{ 1084 int i; 1085 int pages; 1086 vm_object_t ksobj; 1087 vm_offset_t ks; 1088 vm_page_t m; 1089 1090 pages = td->td_kstack_pages; 1091 ksobj = td->td_kstack_obj; 1092 ks = td->td_kstack; 1093 pmap_qremove(ks, pages); 1094 for (i = 0; i < pages; i++) { 1095 m = vm_page_lookup(ksobj, i); 1096 if (m == NULL) 1097 panic("pmap_swapout_thread: kstack already missing?"); 1098 vm_page_lock_queues(); 1099 vm_page_dirty(m); 1100 vm_page_unwire(m, 0); 1101 vm_page_unlock_queues(); 1102 } 1103} 1104 1105/* 1106 * Bring the kernel stack for a specified thread back in. 1107 */ 1108void 1109pmap_swapin_thread(td) 1110 struct thread *td; 1111{ 1112 int i, rv; 1113 int pages; 1114 vm_page_t ma[KSTACK_MAX_PAGES]; 1115 vm_object_t ksobj; 1116 vm_offset_t ks; 1117 vm_page_t m; 1118 1119 pages = td->td_kstack_pages; 1120 ksobj = td->td_kstack_obj; 1121 ks = td->td_kstack; 1122 for (i = 0; i < pages; i++) { 1123 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1124 if (m->valid != VM_PAGE_BITS_ALL) { 1125 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1126 if (rv != VM_PAGER_OK) 1127 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1128 m = vm_page_lookup(ksobj, i); 1129 m->valid = VM_PAGE_BITS_ALL; 1130 } 1131 ma[i] = m; 1132 vm_page_lock_queues(); 1133 vm_page_wire(m); 1134 vm_page_wakeup(m); 1135 vm_page_unlock_queues(); 1136 } 1137 pmap_qenter(ks, ma, pages); 1138} 1139 1140/*************************************************** 1141 * Page table page management routines..... 1142 ***************************************************/ 1143 1144/* 1145 * This routine unholds page table pages, and if the hold count 1146 * drops to zero, then it decrements the wire count. 1147 */ 1148static int 1149_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1150{ 1151 1152 while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) 1153 ; 1154 1155 if (m->hold_count == 0) { 1156 vm_offset_t pteva; 1157 /* 1158 * unmap the page table page 1159 */ 1160 pmap->pm_pdir[m->pindex] = 0; 1161 --pmap->pm_stats.resident_count; 1162 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1163 (PTDpde & PG_FRAME)) { 1164 /* 1165 * Do a invltlb to make the invalidated mapping 1166 * take effect immediately. 1167 */ 1168 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); 1169 pmap_invalidate_page(pmap, pteva); 1170 } 1171 1172 if (pmap->pm_ptphint == m) 1173 pmap->pm_ptphint = NULL; 1174 1175 /* 1176 * If the page is finally unwired, simply free it. 1177 */ 1178 --m->wire_count; 1179 if (m->wire_count == 0) { 1180 vm_page_busy(m); 1181 vm_page_free_zero(m); 1182 --cnt.v_wire_count; 1183 } 1184 return 1; 1185 } 1186 return 0; 1187} 1188 1189static PMAP_INLINE int 1190pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1191{ 1192 vm_page_unhold(m); 1193 if (m->hold_count == 0) 1194 return _pmap_unwire_pte_hold(pmap, m); 1195 else 1196 return 0; 1197} 1198 1199/* 1200 * After removing a page table entry, this routine is used to 1201 * conditionally free the page, and manage the hold/wire counts. 1202 */ 1203static int 1204pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1205{ 1206 unsigned ptepindex; 1207 if (va >= VM_MAXUSER_ADDRESS) 1208 return 0; 1209 1210 if (mpte == NULL) { 1211 ptepindex = (va >> PDRSHIFT); 1212 if (pmap->pm_ptphint && 1213 (pmap->pm_ptphint->pindex == ptepindex)) { 1214 mpte = pmap->pm_ptphint; 1215 } else { 1216 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1217 pmap->pm_ptphint = mpte; 1218 } 1219 } 1220 1221 return pmap_unwire_pte_hold(pmap, mpte); 1222} 1223 1224void 1225pmap_pinit0(pmap) 1226 struct pmap *pmap; 1227{ 1228 pmap->pm_pdir = 1229 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1230 pmap_kenter((vm_offset_t)pmap->pm_pdir, (vm_offset_t)IdlePTD); 1231#ifndef I386_CPU 1232 invlpg((vm_offset_t)pmap->pm_pdir); 1233#else 1234 invltlb(); 1235#endif 1236 pmap->pm_ptphint = NULL; 1237 pmap->pm_active = 0; 1238 TAILQ_INIT(&pmap->pm_pvlist); 1239 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1240 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1241} 1242 1243/* 1244 * Initialize a preallocated and zeroed pmap structure, 1245 * such as one in a vmspace structure. 1246 */ 1247void 1248pmap_pinit(pmap) 1249 register struct pmap *pmap; 1250{ 1251 vm_page_t ptdpg; 1252 1253 /* 1254 * No need to allocate page table space yet but we do need a valid 1255 * page directory table. 1256 */ 1257 if (pmap->pm_pdir == NULL) 1258 pmap->pm_pdir = 1259 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1260 1261 /* 1262 * allocate object for the ptes 1263 */ 1264 if (pmap->pm_pteobj == NULL) 1265 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1266 1267 /* 1268 * allocate the page directory page 1269 */ 1270 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1271 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED | VM_ALLOC_ZERO); 1272 vm_page_flag_clear(ptdpg, PG_BUSY); 1273 ptdpg->valid = VM_PAGE_BITS_ALL; 1274 1275 pmap_qenter((vm_offset_t) pmap->pm_pdir, &ptdpg, 1); 1276 if ((ptdpg->flags & PG_ZERO) == 0) 1277 bzero(pmap->pm_pdir, PAGE_SIZE); 1278 1279 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1280 /* Wire in kernel global address entries. */ 1281 /* XXX copies current process, does not fill in MPPTDI */ 1282 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1283#ifdef SMP 1284 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1285#endif 1286 1287 /* install self-referential address mapping entry */ 1288 pmap->pm_pdir[PTDPTDI] = 1289 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1290 1291 pmap->pm_active = 0; 1292 pmap->pm_ptphint = NULL; 1293 TAILQ_INIT(&pmap->pm_pvlist); 1294 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1295} 1296 1297/* 1298 * Wire in kernel global address entries. To avoid a race condition 1299 * between pmap initialization and pmap_growkernel, this procedure 1300 * should be called after the vmspace is attached to the process 1301 * but before this pmap is activated. 1302 */ 1303void 1304pmap_pinit2(pmap) 1305 struct pmap *pmap; 1306{ 1307 /* XXX: Remove this stub when no longer called */ 1308} 1309 1310static int 1311pmap_release_free_page(pmap_t pmap, vm_page_t p) 1312{ 1313 pd_entry_t *pde = pmap->pm_pdir; 1314 1315 /* 1316 * This code optimizes the case of freeing non-busy 1317 * page-table pages. Those pages are zero now, and 1318 * might as well be placed directly into the zero queue. 1319 */ 1320 vm_page_lock_queues(); 1321 if (vm_page_sleep_if_busy(p, FALSE, "pmaprl")) 1322 return (0); 1323 vm_page_busy(p); 1324 1325 /* 1326 * Remove the page table page from the processes address space. 1327 */ 1328 pde[p->pindex] = 0; 1329 pmap->pm_stats.resident_count--; 1330 1331 if (p->hold_count) { 1332 panic("pmap_release: freeing held page table page"); 1333 } 1334 /* 1335 * Page directory pages need to have the kernel 1336 * stuff cleared, so they can go into the zero queue also. 1337 */ 1338 if (p->pindex == PTDPTDI) { 1339 bzero(pde + KPTDI, nkpt * PTESIZE); 1340#ifdef SMP 1341 pde[MPPTDI] = 0; 1342#endif 1343 pde[APTDPTDI] = 0; 1344 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1345 } 1346 1347 if (pmap->pm_ptphint == p) 1348 pmap->pm_ptphint = NULL; 1349 1350 p->wire_count--; 1351 cnt.v_wire_count--; 1352 vm_page_free_zero(p); 1353 vm_page_unlock_queues(); 1354 return 1; 1355} 1356 1357/* 1358 * this routine is called if the page table page is not 1359 * mapped correctly. 1360 */ 1361static vm_page_t 1362_pmap_allocpte(pmap, ptepindex) 1363 pmap_t pmap; 1364 unsigned ptepindex; 1365{ 1366 vm_offset_t pteva, ptepa; /* XXXPA */ 1367 vm_page_t m; 1368 1369 /* 1370 * Find or fabricate a new pagetable page 1371 */ 1372 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1373 VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1374 1375 KASSERT(m->queue == PQ_NONE, 1376 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1377 1378 /* 1379 * Increment the hold count for the page table page 1380 * (denoting a new mapping.) 1381 */ 1382 m->hold_count++; 1383 1384 /* 1385 * Map the pagetable page into the process address space, if 1386 * it isn't already there. 1387 */ 1388 1389 pmap->pm_stats.resident_count++; 1390 1391 ptepa = VM_PAGE_TO_PHYS(m); 1392 pmap->pm_pdir[ptepindex] = 1393 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1394 1395 /* 1396 * Set the page table hint 1397 */ 1398 pmap->pm_ptphint = m; 1399 1400 /* 1401 * Try to use the new mapping, but if we cannot, then 1402 * do it with the routine that maps the page explicitly. 1403 */ 1404 if ((m->flags & PG_ZERO) == 0) { 1405 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1406 (PTDpde & PG_FRAME)) { 1407 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1408 bzero((caddr_t) pteva, PAGE_SIZE); 1409 } else { 1410 pmap_zero_page(m); 1411 } 1412 } 1413 1414 m->valid = VM_PAGE_BITS_ALL; 1415 vm_page_flag_clear(m, PG_ZERO); 1416 vm_page_wakeup(m); 1417 1418 return m; 1419} 1420 1421static vm_page_t 1422pmap_allocpte(pmap_t pmap, vm_offset_t va) 1423{ 1424 unsigned ptepindex; 1425 pd_entry_t ptepa; 1426 vm_page_t m; 1427 1428 /* 1429 * Calculate pagetable page index 1430 */ 1431 ptepindex = va >> PDRSHIFT; 1432 1433 /* 1434 * Get the page directory entry 1435 */ 1436 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1437 1438 /* 1439 * This supports switching from a 4MB page to a 1440 * normal 4K page. 1441 */ 1442 if (ptepa & PG_PS) { 1443 pmap->pm_pdir[ptepindex] = 0; 1444 ptepa = 0; 1445 pmap_invalidate_all(kernel_pmap); 1446 } 1447 1448 /* 1449 * If the page table page is mapped, we just increment the 1450 * hold count, and activate it. 1451 */ 1452 if (ptepa) { 1453 /* 1454 * In order to get the page table page, try the 1455 * hint first. 1456 */ 1457 if (pmap->pm_ptphint && 1458 (pmap->pm_ptphint->pindex == ptepindex)) { 1459 m = pmap->pm_ptphint; 1460 } else { 1461 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1462 pmap->pm_ptphint = m; 1463 } 1464 m->hold_count++; 1465 return m; 1466 } 1467 /* 1468 * Here if the pte page isn't mapped, or if it has been deallocated. 1469 */ 1470 return _pmap_allocpte(pmap, ptepindex); 1471} 1472 1473 1474/*************************************************** 1475* Pmap allocation/deallocation routines. 1476 ***************************************************/ 1477 1478/* 1479 * Release any resources held by the given physical map. 1480 * Called when a pmap initialized by pmap_pinit is being released. 1481 * Should only be called if the map contains no valid mappings. 1482 */ 1483void 1484pmap_release(pmap_t pmap) 1485{ 1486 vm_page_t p,n,ptdpg; 1487 vm_object_t object = pmap->pm_pteobj; 1488 int curgeneration; 1489 1490#if defined(DIAGNOSTIC) 1491 if (object->ref_count != 1) 1492 panic("pmap_release: pteobj reference count != 1"); 1493#endif 1494 1495 ptdpg = NULL; 1496 LIST_REMOVE(pmap, pm_list); 1497retry: 1498 curgeneration = object->generation; 1499 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1500 n = TAILQ_NEXT(p, listq); 1501 if (p->pindex == PTDPTDI) { 1502 ptdpg = p; 1503 continue; 1504 } 1505 while (1) { 1506 if (!pmap_release_free_page(pmap, p) && 1507 (object->generation != curgeneration)) 1508 goto retry; 1509 } 1510 } 1511 1512 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1513 goto retry; 1514} 1515 1516static int 1517kvm_size(SYSCTL_HANDLER_ARGS) 1518{ 1519 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1520 1521 return sysctl_handle_long(oidp, &ksize, 0, req); 1522} 1523SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1524 0, 0, kvm_size, "IU", "Size of KVM"); 1525 1526static int 1527kvm_free(SYSCTL_HANDLER_ARGS) 1528{ 1529 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1530 1531 return sysctl_handle_long(oidp, &kfree, 0, req); 1532} 1533SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1534 0, 0, kvm_free, "IU", "Amount of KVM free"); 1535 1536/* 1537 * grow the number of kernel page table entries, if needed 1538 */ 1539void 1540pmap_growkernel(vm_offset_t addr) 1541{ 1542 struct pmap *pmap; 1543 int s; 1544 vm_offset_t ptppaddr; 1545 vm_page_t nkpg; 1546 pd_entry_t newpdir; 1547 1548 s = splhigh(); 1549 if (kernel_vm_end == 0) { 1550 kernel_vm_end = KERNBASE; 1551 nkpt = 0; 1552 while (pdir_pde(PTD, kernel_vm_end)) { 1553 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1554 nkpt++; 1555 } 1556 } 1557 addr = roundup2(addr, PAGE_SIZE * NPTEPG); 1558 while (kernel_vm_end < addr) { 1559 if (pdir_pde(PTD, kernel_vm_end)) { 1560 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1561 continue; 1562 } 1563 1564 /* 1565 * This index is bogus, but out of the way 1566 */ 1567 nkpg = vm_page_alloc(kptobj, nkpt, 1568 VM_ALLOC_SYSTEM | VM_ALLOC_WIRED); 1569 if (!nkpg) 1570 panic("pmap_growkernel: no memory to grow kernel"); 1571 1572 nkpt++; 1573 1574 pmap_zero_page(nkpg); 1575 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1576 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1577 pdir_pde(PTD, kernel_vm_end) = newpdir; 1578 1579 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1580 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1581 } 1582 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1583 } 1584 splx(s); 1585} 1586 1587 1588/*************************************************** 1589 * page management routines. 1590 ***************************************************/ 1591 1592/* 1593 * free the pv_entry back to the free list 1594 */ 1595static PMAP_INLINE void 1596free_pv_entry(pv_entry_t pv) 1597{ 1598 pv_entry_count--; 1599 uma_zfree(pvzone, pv); 1600} 1601 1602/* 1603 * get a new pv_entry, allocating a block from the system 1604 * when needed. 1605 * the memory allocation is performed bypassing the malloc code 1606 * because of the possibility of allocations at interrupt time. 1607 */ 1608static pv_entry_t 1609get_pv_entry(void) 1610{ 1611 pv_entry_count++; 1612 if (pv_entry_high_water && 1613 (pv_entry_count > pv_entry_high_water) && 1614 (pmap_pagedaemon_waken == 0)) { 1615 pmap_pagedaemon_waken = 1; 1616 wakeup (&vm_pages_needed); 1617 } 1618 return uma_zalloc(pvzone, M_NOWAIT); 1619} 1620 1621/* 1622 * This routine is very drastic, but can save the system 1623 * in a pinch. 1624 */ 1625void 1626pmap_collect() 1627{ 1628 int i; 1629 vm_page_t m; 1630 static int warningdone = 0; 1631 1632 if (pmap_pagedaemon_waken == 0) 1633 return; 1634 1635 if (warningdone < 5) { 1636 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1637 warningdone++; 1638 } 1639 1640 for(i = 0; i < vm_page_array_size; i++) { 1641 m = &vm_page_array[i]; 1642 if (m->wire_count || m->hold_count || m->busy || 1643 (m->flags & (PG_BUSY | PG_UNMANAGED))) 1644 continue; 1645 pmap_remove_all(m); 1646 } 1647 pmap_pagedaemon_waken = 0; 1648} 1649 1650 1651/* 1652 * If it is the first entry on the list, it is actually 1653 * in the header and we must copy the following entry up 1654 * to the header. Otherwise we must search the list for 1655 * the entry. In either case we free the now unused entry. 1656 */ 1657 1658static int 1659pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1660{ 1661 pv_entry_t pv; 1662 int rtval; 1663 int s; 1664 1665 s = splvm(); 1666 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1667 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1668 if (pmap == pv->pv_pmap && va == pv->pv_va) 1669 break; 1670 } 1671 } else { 1672 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1673 if (va == pv->pv_va) 1674 break; 1675 } 1676 } 1677 1678 rtval = 0; 1679 if (pv) { 1680 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1681 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1682 m->md.pv_list_count--; 1683 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1684 vm_page_flag_clear(m, PG_WRITEABLE); 1685 1686 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1687 free_pv_entry(pv); 1688 } 1689 1690 splx(s); 1691 return rtval; 1692} 1693 1694/* 1695 * Create a pv entry for page at pa for 1696 * (pmap, va). 1697 */ 1698static void 1699pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1700{ 1701 1702 int s; 1703 pv_entry_t pv; 1704 1705 s = splvm(); 1706 pv = get_pv_entry(); 1707 pv->pv_va = va; 1708 pv->pv_pmap = pmap; 1709 pv->pv_ptem = mpte; 1710 1711 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1712 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1713 m->md.pv_list_count++; 1714 1715 splx(s); 1716} 1717 1718/* 1719 * pmap_remove_pte: do the things to unmap a page in a process 1720 */ 1721static int 1722pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1723{ 1724 pt_entry_t oldpte; 1725 vm_page_t m; 1726 1727 oldpte = atomic_readandclear_int(ptq); 1728 if (oldpte & PG_W) 1729 pmap->pm_stats.wired_count -= 1; 1730 /* 1731 * Machines that don't support invlpg, also don't support 1732 * PG_G. 1733 */ 1734 if (oldpte & PG_G) 1735 pmap_invalidate_page(kernel_pmap, va); 1736 pmap->pm_stats.resident_count -= 1; 1737 if (oldpte & PG_MANAGED) { 1738 m = PHYS_TO_VM_PAGE(oldpte); 1739 if (oldpte & PG_M) { 1740#if defined(PMAP_DIAGNOSTIC) 1741 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1742 printf( 1743 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1744 va, oldpte); 1745 } 1746#endif 1747 if (pmap_track_modified(va)) 1748 vm_page_dirty(m); 1749 } 1750 if (oldpte & PG_A) 1751 vm_page_flag_set(m, PG_REFERENCED); 1752 return pmap_remove_entry(pmap, m, va); 1753 } else { 1754 return pmap_unuse_pt(pmap, va, NULL); 1755 } 1756 1757 return 0; 1758} 1759 1760/* 1761 * Remove a single page from a process address space 1762 */ 1763static void 1764pmap_remove_page(pmap_t pmap, vm_offset_t va) 1765{ 1766 register pt_entry_t *ptq; 1767 1768 /* 1769 * if there is no pte for this address, just skip it!!! 1770 */ 1771 if (*pmap_pde(pmap, va) == 0) { 1772 return; 1773 } 1774 1775 /* 1776 * get a local va for mappings for this pmap. 1777 */ 1778 ptq = get_ptbase(pmap) + i386_btop(va); 1779 if (*ptq) { 1780 (void) pmap_remove_pte(pmap, ptq, va); 1781 pmap_invalidate_page(pmap, va); 1782 } 1783 return; 1784} 1785 1786/* 1787 * Remove the given range of addresses from the specified map. 1788 * 1789 * It is assumed that the start and end are properly 1790 * rounded to the page size. 1791 */ 1792void 1793pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1794{ 1795 register pt_entry_t *ptbase; 1796 vm_offset_t pdnxt; 1797 pd_entry_t ptpaddr; 1798 vm_offset_t sindex, eindex; 1799 int anyvalid; 1800 1801 if (pmap == NULL) 1802 return; 1803 1804 if (pmap->pm_stats.resident_count == 0) 1805 return; 1806 1807 /* 1808 * special handling of removing one page. a very 1809 * common operation and easy to short circuit some 1810 * code. 1811 */ 1812 if ((sva + PAGE_SIZE == eva) && 1813 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1814 pmap_remove_page(pmap, sva); 1815 return; 1816 } 1817 1818 anyvalid = 0; 1819 1820 /* 1821 * Get a local virtual address for the mappings that are being 1822 * worked with. 1823 */ 1824 ptbase = get_ptbase(pmap); 1825 1826 sindex = i386_btop(sva); 1827 eindex = i386_btop(eva); 1828 1829 for (; sindex < eindex; sindex = pdnxt) { 1830 unsigned pdirindex; 1831 1832 /* 1833 * Calculate index for next page table. 1834 */ 1835 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1836 if (pmap->pm_stats.resident_count == 0) 1837 break; 1838 1839 pdirindex = sindex / NPDEPG; 1840 ptpaddr = pmap->pm_pdir[pdirindex]; 1841 if ((ptpaddr & PG_PS) != 0) { 1842 pmap->pm_pdir[pdirindex] = 0; 1843 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1844 anyvalid++; 1845 continue; 1846 } 1847 1848 /* 1849 * Weed out invalid mappings. Note: we assume that the page 1850 * directory table is always allocated, and in kernel virtual. 1851 */ 1852 if (ptpaddr == 0) 1853 continue; 1854 1855 /* 1856 * Limit our scan to either the end of the va represented 1857 * by the current page table page, or to the end of the 1858 * range being removed. 1859 */ 1860 if (pdnxt > eindex) { 1861 pdnxt = eindex; 1862 } 1863 1864 for (; sindex != pdnxt; sindex++) { 1865 vm_offset_t va; 1866 if (ptbase[sindex] == 0) { 1867 continue; 1868 } 1869 va = i386_ptob(sindex); 1870 1871 anyvalid++; 1872 if (pmap_remove_pte(pmap, 1873 ptbase + sindex, va)) 1874 break; 1875 } 1876 } 1877 1878 if (anyvalid) 1879 pmap_invalidate_all(pmap); 1880} 1881 1882/* 1883 * Routine: pmap_remove_all 1884 * Function: 1885 * Removes this physical page from 1886 * all physical maps in which it resides. 1887 * Reflects back modify bits to the pager. 1888 * 1889 * Notes: 1890 * Original versions of this routine were very 1891 * inefficient because they iteratively called 1892 * pmap_remove (slow...) 1893 */ 1894 1895void 1896pmap_remove_all(vm_page_t m) 1897{ 1898 register pv_entry_t pv; 1899 pt_entry_t *pte, tpte; 1900 int s; 1901 1902#if defined(PMAP_DIAGNOSTIC) 1903 /* 1904 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1905 * pages! 1906 */ 1907 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1908 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1909 } 1910#endif 1911 1912 s = splvm(); 1913 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1914 pv->pv_pmap->pm_stats.resident_count--; 1915 1916 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1917 1918 tpte = atomic_readandclear_int(pte); 1919 if (tpte & PG_W) 1920 pv->pv_pmap->pm_stats.wired_count--; 1921 1922 if (tpte & PG_A) 1923 vm_page_flag_set(m, PG_REFERENCED); 1924 1925 /* 1926 * Update the vm_page_t clean and reference bits. 1927 */ 1928 if (tpte & PG_M) { 1929#if defined(PMAP_DIAGNOSTIC) 1930 if (pmap_nw_modified((pt_entry_t) tpte)) { 1931 printf( 1932 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1933 pv->pv_va, tpte); 1934 } 1935#endif 1936 if (pmap_track_modified(pv->pv_va)) 1937 vm_page_dirty(m); 1938 } 1939 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1940 1941 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1942 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1943 m->md.pv_list_count--; 1944 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1945 free_pv_entry(pv); 1946 } 1947 1948 vm_page_flag_clear(m, PG_WRITEABLE); 1949 1950 splx(s); 1951} 1952 1953/* 1954 * Set the physical protection on the 1955 * specified range of this map as requested. 1956 */ 1957void 1958pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1959{ 1960 register pt_entry_t *ptbase; 1961 vm_offset_t pdnxt; 1962 pd_entry_t ptpaddr; 1963 vm_offset_t sindex, eindex; 1964 int anychanged; 1965 1966 if (pmap == NULL) 1967 return; 1968 1969 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1970 pmap_remove(pmap, sva, eva); 1971 return; 1972 } 1973 1974 if (prot & VM_PROT_WRITE) 1975 return; 1976 1977 anychanged = 0; 1978 1979 ptbase = get_ptbase(pmap); 1980 1981 sindex = i386_btop(sva); 1982 eindex = i386_btop(eva); 1983 1984 for (; sindex < eindex; sindex = pdnxt) { 1985 1986 unsigned pdirindex; 1987 1988 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1989 1990 pdirindex = sindex / NPDEPG; 1991 ptpaddr = pmap->pm_pdir[pdirindex]; 1992 if ((ptpaddr & PG_PS) != 0) { 1993 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1994 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1995 anychanged++; 1996 continue; 1997 } 1998 1999 /* 2000 * Weed out invalid mappings. Note: we assume that the page 2001 * directory table is always allocated, and in kernel virtual. 2002 */ 2003 if (ptpaddr == 0) 2004 continue; 2005 2006 if (pdnxt > eindex) { 2007 pdnxt = eindex; 2008 } 2009 2010 for (; sindex != pdnxt; sindex++) { 2011 2012 pt_entry_t pbits; 2013 vm_page_t m; 2014 2015 pbits = ptbase[sindex]; 2016 2017 if (pbits & PG_MANAGED) { 2018 m = NULL; 2019 if (pbits & PG_A) { 2020 m = PHYS_TO_VM_PAGE(pbits); 2021 vm_page_flag_set(m, PG_REFERENCED); 2022 pbits &= ~PG_A; 2023 } 2024 if (pbits & PG_M) { 2025 if (pmap_track_modified(i386_ptob(sindex))) { 2026 if (m == NULL) 2027 m = PHYS_TO_VM_PAGE(pbits); 2028 vm_page_dirty(m); 2029 pbits &= ~PG_M; 2030 } 2031 } 2032 } 2033 2034 pbits &= ~PG_RW; 2035 2036 if (pbits != ptbase[sindex]) { 2037 ptbase[sindex] = pbits; 2038 anychanged = 1; 2039 } 2040 } 2041 } 2042 if (anychanged) 2043 pmap_invalidate_all(pmap); 2044} 2045 2046/* 2047 * Insert the given physical page (p) at 2048 * the specified virtual address (v) in the 2049 * target physical map with the protection requested. 2050 * 2051 * If specified, the page will be wired down, meaning 2052 * that the related pte can not be reclaimed. 2053 * 2054 * NB: This is the only routine which MAY NOT lazy-evaluate 2055 * or lose information. That is, this routine must actually 2056 * insert this page into the given map NOW. 2057 */ 2058void 2059pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2060 boolean_t wired) 2061{ 2062 vm_offset_t pa; 2063 register pt_entry_t *pte; 2064 vm_offset_t opa; 2065 pt_entry_t origpte, newpte; 2066 vm_page_t mpte; 2067 2068 if (pmap == NULL) 2069 return; 2070 2071 va &= PG_FRAME; 2072#ifdef PMAP_DIAGNOSTIC 2073 if (va > VM_MAX_KERNEL_ADDRESS) 2074 panic("pmap_enter: toobig"); 2075 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2076 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2077#endif 2078 2079 mpte = NULL; 2080 /* 2081 * In the case that a page table page is not 2082 * resident, we are creating it here. 2083 */ 2084 if (va < VM_MAXUSER_ADDRESS) { 2085 mpte = pmap_allocpte(pmap, va); 2086 } 2087#if 0 && defined(PMAP_DIAGNOSTIC) 2088 else { 2089 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2090 origpte = *pdeaddr; 2091 if ((origpte & PG_V) == 0) { 2092 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2093 pmap->pm_pdir[PTDPTDI], origpte, va); 2094 } 2095 } 2096#endif 2097 2098 pte = pmap_pte(pmap, va); 2099 2100 /* 2101 * Page Directory table entry not valid, we need a new PT page 2102 */ 2103 if (pte == NULL) { 2104 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2105 (void *)pmap->pm_pdir[PTDPTDI], va); 2106 } 2107 2108 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2109 origpte = *(vm_offset_t *)pte; 2110 opa = origpte & PG_FRAME; 2111 2112 if (origpte & PG_PS) 2113 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2114 2115 /* 2116 * Mapping has not changed, must be protection or wiring change. 2117 */ 2118 if (origpte && (opa == pa)) { 2119 /* 2120 * Wiring change, just update stats. We don't worry about 2121 * wiring PT pages as they remain resident as long as there 2122 * are valid mappings in them. Hence, if a user page is wired, 2123 * the PT page will be also. 2124 */ 2125 if (wired && ((origpte & PG_W) == 0)) 2126 pmap->pm_stats.wired_count++; 2127 else if (!wired && (origpte & PG_W)) 2128 pmap->pm_stats.wired_count--; 2129 2130#if defined(PMAP_DIAGNOSTIC) 2131 if (pmap_nw_modified((pt_entry_t) origpte)) { 2132 printf( 2133 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2134 va, origpte); 2135 } 2136#endif 2137 2138 /* 2139 * Remove extra pte reference 2140 */ 2141 if (mpte) 2142 mpte->hold_count--; 2143 2144 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2145 if ((origpte & PG_RW) == 0) { 2146 *pte |= PG_RW; 2147 pmap_invalidate_page(pmap, va); 2148 } 2149 return; 2150 } 2151 2152 /* 2153 * We might be turning off write access to the page, 2154 * so we go ahead and sense modify status. 2155 */ 2156 if (origpte & PG_MANAGED) { 2157 if ((origpte & PG_M) && pmap_track_modified(va)) { 2158 vm_page_t om; 2159 om = PHYS_TO_VM_PAGE(opa); 2160 vm_page_dirty(om); 2161 } 2162 pa |= PG_MANAGED; 2163 } 2164 goto validate; 2165 } 2166 /* 2167 * Mapping has changed, invalidate old range and fall through to 2168 * handle validating new mapping. 2169 */ 2170 if (opa) { 2171 int err; 2172 err = pmap_remove_pte(pmap, pte, va); 2173 if (err) 2174 panic("pmap_enter: pte vanished, va: 0x%x", va); 2175 } 2176 2177 /* 2178 * Enter on the PV list if part of our managed memory. Note that we 2179 * raise IPL while manipulating pv_table since pmap_enter can be 2180 * called at interrupt time. 2181 */ 2182 if (pmap_initialized && 2183 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2184 pmap_insert_entry(pmap, va, mpte, m); 2185 pa |= PG_MANAGED; 2186 } 2187 2188 /* 2189 * Increment counters 2190 */ 2191 pmap->pm_stats.resident_count++; 2192 if (wired) 2193 pmap->pm_stats.wired_count++; 2194 2195validate: 2196 /* 2197 * Now validate mapping with desired protection/wiring. 2198 */ 2199 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2200 2201 if (wired) 2202 newpte |= PG_W; 2203 if (va < VM_MAXUSER_ADDRESS) 2204 newpte |= PG_U; 2205 if (pmap == kernel_pmap) 2206 newpte |= pgeflag; 2207 2208 /* 2209 * if the mapping or permission bits are different, we need 2210 * to update the pte. 2211 */ 2212 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2213 *pte = newpte | PG_A; 2214 /*if (origpte)*/ { 2215 pmap_invalidate_page(pmap, va); 2216 } 2217 } 2218} 2219 2220/* 2221 * this code makes some *MAJOR* assumptions: 2222 * 1. Current pmap & pmap exists. 2223 * 2. Not wired. 2224 * 3. Read access. 2225 * 4. No page table pages. 2226 * 5. Tlbflush is deferred to calling procedure. 2227 * 6. Page IS managed. 2228 * but is *MUCH* faster than pmap_enter... 2229 */ 2230 2231static vm_page_t 2232pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2233{ 2234 pt_entry_t *pte; 2235 vm_offset_t pa; 2236 2237 /* 2238 * In the case that a page table page is not 2239 * resident, we are creating it here. 2240 */ 2241 if (va < VM_MAXUSER_ADDRESS) { 2242 unsigned ptepindex; 2243 pd_entry_t ptepa; 2244 2245 /* 2246 * Calculate pagetable page index 2247 */ 2248 ptepindex = va >> PDRSHIFT; 2249 if (mpte && (mpte->pindex == ptepindex)) { 2250 mpte->hold_count++; 2251 } else { 2252retry: 2253 /* 2254 * Get the page directory entry 2255 */ 2256 ptepa = pmap->pm_pdir[ptepindex]; 2257 2258 /* 2259 * If the page table page is mapped, we just increment 2260 * the hold count, and activate it. 2261 */ 2262 if (ptepa) { 2263 if (ptepa & PG_PS) 2264 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2265 if (pmap->pm_ptphint && 2266 (pmap->pm_ptphint->pindex == ptepindex)) { 2267 mpte = pmap->pm_ptphint; 2268 } else { 2269 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2270 pmap->pm_ptphint = mpte; 2271 } 2272 if (mpte == NULL) 2273 goto retry; 2274 mpte->hold_count++; 2275 } else { 2276 mpte = _pmap_allocpte(pmap, ptepindex); 2277 } 2278 } 2279 } else { 2280 mpte = NULL; 2281 } 2282 2283 /* 2284 * This call to vtopte makes the assumption that we are 2285 * entering the page into the current pmap. In order to support 2286 * quick entry into any pmap, one would likely use pmap_pte_quick. 2287 * But that isn't as quick as vtopte. 2288 */ 2289 pte = vtopte(va); 2290 if (*pte) { 2291 if (mpte) 2292 pmap_unwire_pte_hold(pmap, mpte); 2293 return 0; 2294 } 2295 2296 /* 2297 * Enter on the PV list if part of our managed memory. Note that we 2298 * raise IPL while manipulating pv_table since pmap_enter can be 2299 * called at interrupt time. 2300 */ 2301 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2302 pmap_insert_entry(pmap, va, mpte, m); 2303 2304 /* 2305 * Increment counters 2306 */ 2307 pmap->pm_stats.resident_count++; 2308 2309 pa = VM_PAGE_TO_PHYS(m); 2310 2311 /* 2312 * Now validate mapping with RO protection 2313 */ 2314 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2315 *pte = pa | PG_V | PG_U; 2316 else 2317 *pte = pa | PG_V | PG_U | PG_MANAGED; 2318 2319 return mpte; 2320} 2321 2322/* 2323 * Make a temporary mapping for a physical address. This is only intended 2324 * to be used for panic dumps. 2325 */ 2326void * 2327pmap_kenter_temporary(vm_offset_t pa, int i) 2328{ 2329 vm_offset_t va; 2330 2331 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE); 2332 pmap_kenter(va, pa); 2333#ifndef I386_CPU 2334 invlpg(va); 2335#else 2336 invltlb(); 2337#endif 2338 return ((void *)crashdumpmap); 2339} 2340 2341#define MAX_INIT_PT (96) 2342/* 2343 * pmap_object_init_pt preloads the ptes for a given object 2344 * into the specified pmap. This eliminates the blast of soft 2345 * faults on process startup and immediately after an mmap. 2346 */ 2347void 2348pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2349 vm_object_t object, vm_pindex_t pindex, 2350 vm_size_t size, int limit) 2351{ 2352 vm_offset_t tmpidx; 2353 int psize; 2354 vm_page_t p, mpte; 2355 2356 if (pmap == NULL || object == NULL) 2357 return; 2358 2359 /* 2360 * This code maps large physical mmap regions into the 2361 * processor address space. Note that some shortcuts 2362 * are taken, but the code works. 2363 */ 2364 if (pseflag && (object->type == OBJT_DEVICE) && 2365 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2366 int i; 2367 vm_page_t m[1]; 2368 unsigned int ptepindex; 2369 int npdes; 2370 pd_entry_t ptepa; 2371 2372 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2373 return; 2374 2375retry: 2376 p = vm_page_lookup(object, pindex); 2377 if (p != NULL) { 2378 vm_page_lock_queues(); 2379 if (vm_page_sleep_if_busy(p, FALSE, "init4p")) 2380 goto retry; 2381 vm_page_unlock_queues(); 2382 } else { 2383 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2384 if (p == NULL) 2385 return; 2386 m[0] = p; 2387 2388 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2389 vm_page_lock_queues(); 2390 vm_page_free(p); 2391 vm_page_unlock_queues(); 2392 return; 2393 } 2394 2395 p = vm_page_lookup(object, pindex); 2396 vm_page_wakeup(p); 2397 } 2398 2399 ptepa = VM_PAGE_TO_PHYS(p); 2400 if (ptepa & (NBPDR - 1)) { 2401 return; 2402 } 2403 2404 p->valid = VM_PAGE_BITS_ALL; 2405 2406 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2407 npdes = size >> PDRSHIFT; 2408 for(i = 0; i < npdes; i++) { 2409 pmap->pm_pdir[ptepindex] = 2410 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2411 ptepa += NBPDR; 2412 ptepindex += 1; 2413 } 2414 pmap_invalidate_all(kernel_pmap); 2415 return; 2416 } 2417 2418 psize = i386_btop(size); 2419 2420 if ((object->type != OBJT_VNODE) || 2421 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2422 (object->resident_page_count > MAX_INIT_PT))) { 2423 return; 2424 } 2425 2426 if (psize + pindex > object->size) { 2427 if (object->size < pindex) 2428 return; 2429 psize = object->size - pindex; 2430 } 2431 2432 mpte = NULL; 2433 2434 if ((p = TAILQ_FIRST(&object->memq)) != NULL) { 2435 if (p->pindex < pindex) { 2436 p = vm_page_splay(pindex, object->root); 2437 if ((object->root = p)->pindex < pindex) 2438 p = TAILQ_NEXT(p, listq); 2439 } 2440 } 2441 /* 2442 * Assert: the variable p is either (1) the page with the 2443 * least pindex greater than or equal to the parameter pindex 2444 * or (2) NULL. 2445 */ 2446 for (; 2447 p != NULL && (tmpidx = p->pindex - pindex) < psize; 2448 p = TAILQ_NEXT(p, listq)) { 2449 /* 2450 * don't allow an madvise to blow away our really 2451 * free pages allocating pv entries. 2452 */ 2453 if ((limit & MAP_PREFAULT_MADVISE) && 2454 cnt.v_free_count < cnt.v_free_reserved) { 2455 break; 2456 } 2457 vm_page_lock_queues(); 2458 if ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL && 2459 (p->busy == 0) && 2460 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2461 if ((p->queue - p->pc) == PQ_CACHE) 2462 vm_page_deactivate(p); 2463 vm_page_busy(p); 2464 vm_page_unlock_queues(); 2465 mpte = pmap_enter_quick(pmap, 2466 addr + i386_ptob(tmpidx), p, mpte); 2467 vm_page_lock_queues(); 2468 vm_page_wakeup(p); 2469 } 2470 vm_page_unlock_queues(); 2471 } 2472 return; 2473} 2474 2475/* 2476 * pmap_prefault provides a quick way of clustering 2477 * pagefaults into a processes address space. It is a "cousin" 2478 * of pmap_object_init_pt, except it runs at page fault time instead 2479 * of mmap time. 2480 */ 2481#define PFBAK 4 2482#define PFFOR 4 2483#define PAGEORDER_SIZE (PFBAK+PFFOR) 2484 2485static int pmap_prefault_pageorder[] = { 2486 -1 * PAGE_SIZE, 1 * PAGE_SIZE, 2487 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2488 -3 * PAGE_SIZE, 3 * PAGE_SIZE, 2489 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2490}; 2491 2492void 2493pmap_prefault(pmap, addra, entry) 2494 pmap_t pmap; 2495 vm_offset_t addra; 2496 vm_map_entry_t entry; 2497{ 2498 int i; 2499 vm_offset_t starta; 2500 vm_offset_t addr; 2501 vm_pindex_t pindex; 2502 vm_page_t m, mpte; 2503 vm_object_t object; 2504 2505 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2506 return; 2507 2508 object = entry->object.vm_object; 2509 2510 starta = addra - PFBAK * PAGE_SIZE; 2511 if (starta < entry->start) { 2512 starta = entry->start; 2513 } else if (starta > addra) { 2514 starta = 0; 2515 } 2516 2517 mpte = NULL; 2518 for (i = 0; i < PAGEORDER_SIZE; i++) { 2519 vm_object_t lobject; 2520 pt_entry_t *pte; 2521 2522 addr = addra + pmap_prefault_pageorder[i]; 2523 if (addr > addra + (PFFOR * PAGE_SIZE)) 2524 addr = 0; 2525 2526 if (addr < starta || addr >= entry->end) 2527 continue; 2528 2529 if ((*pmap_pde(pmap, addr)) == 0) 2530 continue; 2531 2532 pte = vtopte(addr); 2533 if (*pte) 2534 continue; 2535 2536 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2537 lobject = object; 2538 for (m = vm_page_lookup(lobject, pindex); 2539 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2540 lobject = lobject->backing_object) { 2541 if (lobject->backing_object_offset & PAGE_MASK) 2542 break; 2543 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2544 m = vm_page_lookup(lobject->backing_object, pindex); 2545 } 2546 2547 /* 2548 * give-up when a page is not in memory 2549 */ 2550 if (m == NULL) 2551 break; 2552 vm_page_lock_queues(); 2553 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2554 (m->busy == 0) && 2555 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2556 2557 if ((m->queue - m->pc) == PQ_CACHE) { 2558 vm_page_deactivate(m); 2559 } 2560 vm_page_busy(m); 2561 vm_page_unlock_queues(); 2562 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2563 vm_page_lock_queues(); 2564 vm_page_wakeup(m); 2565 } 2566 vm_page_unlock_queues(); 2567 } 2568} 2569 2570/* 2571 * Routine: pmap_change_wiring 2572 * Function: Change the wiring attribute for a map/virtual-address 2573 * pair. 2574 * In/out conditions: 2575 * The mapping must already exist in the pmap. 2576 */ 2577void 2578pmap_change_wiring(pmap, va, wired) 2579 register pmap_t pmap; 2580 vm_offset_t va; 2581 boolean_t wired; 2582{ 2583 register pt_entry_t *pte; 2584 2585 if (pmap == NULL) 2586 return; 2587 2588 pte = pmap_pte(pmap, va); 2589 2590 if (wired && !pmap_pte_w(pte)) 2591 pmap->pm_stats.wired_count++; 2592 else if (!wired && pmap_pte_w(pte)) 2593 pmap->pm_stats.wired_count--; 2594 2595 /* 2596 * Wiring is not a hardware characteristic so there is no need to 2597 * invalidate TLB. 2598 */ 2599 pmap_pte_set_w(pte, wired); 2600} 2601 2602 2603 2604/* 2605 * Copy the range specified by src_addr/len 2606 * from the source map to the range dst_addr/len 2607 * in the destination map. 2608 * 2609 * This routine is only advisory and need not do anything. 2610 */ 2611 2612void 2613pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2614 vm_offset_t src_addr) 2615{ 2616 vm_offset_t addr; 2617 vm_offset_t end_addr = src_addr + len; 2618 vm_offset_t pdnxt; 2619 pd_entry_t src_frame, dst_frame; 2620 vm_page_t m; 2621 2622 if (dst_addr != src_addr) 2623 return; 2624 2625 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2626 if (src_frame != (PTDpde & PG_FRAME)) 2627 return; 2628 2629 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2630 for (addr = src_addr; addr < end_addr; addr = pdnxt) { 2631 pt_entry_t *src_pte, *dst_pte; 2632 vm_page_t dstmpte, srcmpte; 2633 pd_entry_t srcptepaddr; 2634 unsigned ptepindex; 2635 2636 if (addr >= UPT_MIN_ADDRESS) 2637 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2638 2639 /* 2640 * Don't let optional prefaulting of pages make us go 2641 * way below the low water mark of free pages or way 2642 * above high water mark of used pv entries. 2643 */ 2644 if (cnt.v_free_count < cnt.v_free_reserved || 2645 pv_entry_count > pv_entry_high_water) 2646 break; 2647 2648 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2649 ptepindex = addr >> PDRSHIFT; 2650 2651 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2652 if (srcptepaddr == 0) 2653 continue; 2654 2655 if (srcptepaddr & PG_PS) { 2656 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2657 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2658 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2659 } 2660 continue; 2661 } 2662 2663 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2664 if ((srcmpte == NULL) || 2665 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2666 continue; 2667 2668 if (pdnxt > end_addr) 2669 pdnxt = end_addr; 2670 2671 /* 2672 * Have to recheck this before every avtopte() call below 2673 * in case we have blocked and something else used APTDpde. 2674 */ 2675 if (dst_frame != (APTDpde & PG_FRAME)) { 2676 APTDpde = dst_frame | PG_RW | PG_V; 2677 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 2678 } 2679 src_pte = vtopte(addr); 2680 dst_pte = avtopte(addr); 2681 while (addr < pdnxt) { 2682 pt_entry_t ptetemp; 2683 ptetemp = *src_pte; 2684 /* 2685 * we only virtual copy managed pages 2686 */ 2687 if ((ptetemp & PG_MANAGED) != 0) { 2688 /* 2689 * We have to check after allocpte for the 2690 * pte still being around... allocpte can 2691 * block. 2692 */ 2693 dstmpte = pmap_allocpte(dst_pmap, addr); 2694 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2695 /* 2696 * Clear the modified and 2697 * accessed (referenced) bits 2698 * during the copy. 2699 */ 2700 m = PHYS_TO_VM_PAGE(ptetemp); 2701 *dst_pte = ptetemp & ~(PG_M | PG_A); 2702 dst_pmap->pm_stats.resident_count++; 2703 pmap_insert_entry(dst_pmap, addr, 2704 dstmpte, m); 2705 } else { 2706 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2707 } 2708 if (dstmpte->hold_count >= srcmpte->hold_count) 2709 break; 2710 } 2711 addr += PAGE_SIZE; 2712 src_pte++; 2713 dst_pte++; 2714 } 2715 } 2716} 2717 2718#ifdef SMP 2719 2720/* 2721 * pmap_zpi_switchin*() 2722 * 2723 * These functions allow us to avoid doing IPIs alltogether in certain 2724 * temporary page-mapping situations (page zeroing). Instead to deal 2725 * with being preempted and moved onto a different cpu we invalidate 2726 * the page when the scheduler switches us in. This does not occur 2727 * very often so we remain relatively optimal with very little effort. 2728 */ 2729static void 2730pmap_zpi_switchin12(void) 2731{ 2732 invlpg((u_int)CADDR1); 2733 invlpg((u_int)CADDR2); 2734} 2735 2736static void 2737pmap_zpi_switchin2(void) 2738{ 2739 invlpg((u_int)CADDR2); 2740} 2741 2742static void 2743pmap_zpi_switchin3(void) 2744{ 2745 invlpg((u_int)CADDR3); 2746} 2747 2748#endif 2749 2750/* 2751 * pmap_zero_page zeros the specified hardware page by mapping 2752 * the page into KVM and using bzero to clear its contents. 2753 */ 2754void 2755pmap_zero_page(vm_page_t m) 2756{ 2757 vm_offset_t phys; 2758 2759 phys = VM_PAGE_TO_PHYS(m); 2760 if (*CMAP2) 2761 panic("pmap_zero_page: CMAP2 busy"); 2762 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2763#ifdef I386_CPU 2764 invltlb(); 2765#else 2766#ifdef SMP 2767 curthread->td_switchin = pmap_zpi_switchin2; 2768#endif 2769 invlpg((u_int)CADDR2); 2770#endif 2771#if defined(I686_CPU) 2772 if (cpu_class == CPUCLASS_686) 2773 i686_pagezero(CADDR2); 2774 else 2775#endif 2776 bzero(CADDR2, PAGE_SIZE); 2777#ifdef SMP 2778 curthread->td_switchin = NULL; 2779#endif 2780 *CMAP2 = 0; 2781} 2782 2783/* 2784 * pmap_zero_page_area zeros the specified hardware page by mapping 2785 * the page into KVM and using bzero to clear its contents. 2786 * 2787 * off and size may not cover an area beyond a single hardware page. 2788 */ 2789void 2790pmap_zero_page_area(vm_page_t m, int off, int size) 2791{ 2792 vm_offset_t phys; 2793 2794 phys = VM_PAGE_TO_PHYS(m); 2795 if (*CMAP2) 2796 panic("pmap_zero_page: CMAP2 busy"); 2797 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2798#ifdef I386_CPU 2799 invltlb(); 2800#else 2801#ifdef SMP 2802 curthread->td_switchin = pmap_zpi_switchin2; 2803#endif 2804 invlpg((u_int)CADDR2); 2805#endif 2806#if defined(I686_CPU) 2807 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2808 i686_pagezero(CADDR2); 2809 else 2810#endif 2811 bzero((char *)CADDR2 + off, size); 2812#ifdef SMP 2813 curthread->td_switchin = NULL; 2814#endif 2815 *CMAP2 = 0; 2816} 2817 2818/* 2819 * pmap_zero_page_idle zeros the specified hardware page by mapping 2820 * the page into KVM and using bzero to clear its contents. This 2821 * is intended to be called from the vm_pagezero process only and 2822 * outside of Giant. 2823 */ 2824void 2825pmap_zero_page_idle(vm_page_t m) 2826{ 2827 vm_offset_t phys; 2828 2829 phys = VM_PAGE_TO_PHYS(m); 2830 if (*CMAP3) 2831 panic("pmap_zero_page: CMAP3 busy"); 2832 *CMAP3 = PG_V | PG_RW | phys | PG_A | PG_M; 2833#ifdef I386_CPU 2834 invltlb(); 2835#else 2836#ifdef SMP 2837 curthread->td_switchin = pmap_zpi_switchin3; 2838#endif 2839 invlpg((u_int)CADDR3); 2840#endif 2841#if defined(I686_CPU) 2842 if (cpu_class == CPUCLASS_686) 2843 i686_pagezero(CADDR3); 2844 else 2845#endif 2846 bzero(CADDR3, PAGE_SIZE); 2847#ifdef SMP 2848 curthread->td_switchin = NULL; 2849#endif 2850 *CMAP3 = 0; 2851} 2852 2853/* 2854 * pmap_copy_page copies the specified (machine independent) 2855 * page by mapping the page into virtual memory and using 2856 * bcopy to copy the page, one machine dependent page at a 2857 * time. 2858 */ 2859void 2860pmap_copy_page(vm_page_t src, vm_page_t dst) 2861{ 2862 2863 if (*CMAP1) 2864 panic("pmap_copy_page: CMAP1 busy"); 2865 if (*CMAP2) 2866 panic("pmap_copy_page: CMAP2 busy"); 2867 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2868 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2869#ifdef I386_CPU 2870 invltlb(); 2871#else 2872#ifdef SMP 2873 curthread->td_switchin = pmap_zpi_switchin12; 2874#endif 2875 invlpg((u_int)CADDR1); 2876 invlpg((u_int)CADDR2); 2877#endif 2878 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2879#ifdef SMP 2880 curthread->td_switchin = NULL; 2881#endif 2882 *CMAP1 = 0; 2883 *CMAP2 = 0; 2884} 2885 2886/* 2887 * Returns true if the pmap's pv is one of the first 2888 * 16 pvs linked to from this page. This count may 2889 * be changed upwards or downwards in the future; it 2890 * is only necessary that true be returned for a small 2891 * subset of pmaps for proper page aging. 2892 */ 2893boolean_t 2894pmap_page_exists_quick(pmap, m) 2895 pmap_t pmap; 2896 vm_page_t m; 2897{ 2898 pv_entry_t pv; 2899 int loops = 0; 2900 int s; 2901 2902 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2903 return FALSE; 2904 2905 s = splvm(); 2906 2907 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2908 if (pv->pv_pmap == pmap) { 2909 splx(s); 2910 return TRUE; 2911 } 2912 loops++; 2913 if (loops >= 16) 2914 break; 2915 } 2916 splx(s); 2917 return (FALSE); 2918} 2919 2920#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2921/* 2922 * Remove all pages from specified address space 2923 * this aids process exit speeds. Also, this code 2924 * is special cased for current process only, but 2925 * can have the more generic (and slightly slower) 2926 * mode enabled. This is much faster than pmap_remove 2927 * in the case of running down an entire address space. 2928 */ 2929void 2930pmap_remove_pages(pmap, sva, eva) 2931 pmap_t pmap; 2932 vm_offset_t sva, eva; 2933{ 2934 pt_entry_t *pte, tpte; 2935 vm_page_t m; 2936 pv_entry_t pv, npv; 2937 int s; 2938 2939#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2940 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2941 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2942 return; 2943 } 2944#endif 2945 2946 s = splvm(); 2947 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2948 2949 if (pv->pv_va >= eva || pv->pv_va < sva) { 2950 npv = TAILQ_NEXT(pv, pv_plist); 2951 continue; 2952 } 2953 2954#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2955 pte = vtopte(pv->pv_va); 2956#else 2957 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2958#endif 2959 tpte = *pte; 2960 2961 if (tpte == 0) { 2962 printf("TPTE at %p IS ZERO @ VA %08x\n", 2963 pte, pv->pv_va); 2964 panic("bad pte"); 2965 } 2966 2967/* 2968 * We cannot remove wired pages from a process' mapping at this time 2969 */ 2970 if (tpte & PG_W) { 2971 npv = TAILQ_NEXT(pv, pv_plist); 2972 continue; 2973 } 2974 2975 m = PHYS_TO_VM_PAGE(tpte); 2976 KASSERT(m->phys_addr == (tpte & PG_FRAME), 2977 ("vm_page_t %p phys_addr mismatch %08x %08x", 2978 m, m->phys_addr, tpte)); 2979 2980 KASSERT(m < &vm_page_array[vm_page_array_size], 2981 ("pmap_remove_pages: bad tpte %x", tpte)); 2982 2983 pv->pv_pmap->pm_stats.resident_count--; 2984 2985 *pte = 0; 2986 2987 /* 2988 * Update the vm_page_t clean and reference bits. 2989 */ 2990 if (tpte & PG_M) { 2991 vm_page_dirty(m); 2992 } 2993 2994 npv = TAILQ_NEXT(pv, pv_plist); 2995 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 2996 2997 m->md.pv_list_count--; 2998 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 2999 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 3000 vm_page_flag_clear(m, PG_WRITEABLE); 3001 } 3002 3003 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 3004 free_pv_entry(pv); 3005 } 3006 splx(s); 3007 pmap_invalidate_all(pmap); 3008} 3009 3010/* 3011 * pmap_testbit tests bits in pte's 3012 * note that the testbit/changebit routines are inline, 3013 * and a lot of things compile-time evaluate. 3014 */ 3015static boolean_t 3016pmap_testbit(m, bit) 3017 vm_page_t m; 3018 int bit; 3019{ 3020 pv_entry_t pv; 3021 pt_entry_t *pte; 3022 int s; 3023 3024 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3025 return FALSE; 3026 3027 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 3028 return FALSE; 3029 3030 s = splvm(); 3031 3032 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3033 /* 3034 * if the bit being tested is the modified bit, then 3035 * mark clean_map and ptes as never 3036 * modified. 3037 */ 3038 if (bit & (PG_A|PG_M)) { 3039 if (!pmap_track_modified(pv->pv_va)) 3040 continue; 3041 } 3042 3043#if defined(PMAP_DIAGNOSTIC) 3044 if (!pv->pv_pmap) { 3045 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3046 continue; 3047 } 3048#endif 3049 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3050 if (*pte & bit) { 3051 splx(s); 3052 return TRUE; 3053 } 3054 } 3055 splx(s); 3056 return (FALSE); 3057} 3058 3059/* 3060 * this routine is used to modify bits in ptes 3061 */ 3062static __inline void 3063pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3064{ 3065 register pv_entry_t pv; 3066 register pt_entry_t *pte; 3067 int s; 3068 3069 if (!pmap_initialized || (m->flags & PG_FICTITIOUS) || 3070 (!setem && bit == PG_RW && (m->flags & PG_WRITEABLE) == 0)) 3071 return; 3072 3073 s = splvm(); 3074 3075 /* 3076 * Loop over all current mappings setting/clearing as appropos If 3077 * setting RO do we need to clear the VAC? 3078 */ 3079 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3080 /* 3081 * don't write protect pager mappings 3082 */ 3083 if (!setem && (bit == PG_RW)) { 3084 if (!pmap_track_modified(pv->pv_va)) 3085 continue; 3086 } 3087 3088#if defined(PMAP_DIAGNOSTIC) 3089 if (!pv->pv_pmap) { 3090 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3091 continue; 3092 } 3093#endif 3094 3095 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3096 3097 if (setem) { 3098 *pte |= bit; 3099 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3100 } else { 3101 pt_entry_t pbits = *pte; 3102 if (pbits & bit) { 3103 if (bit == PG_RW) { 3104 if (pbits & PG_M) { 3105 vm_page_dirty(m); 3106 } 3107 *pte = pbits & ~(PG_M|PG_RW); 3108 } else { 3109 *pte = pbits & ~bit; 3110 } 3111 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3112 } 3113 } 3114 } 3115 if (!setem && bit == PG_RW) 3116 vm_page_flag_clear(m, PG_WRITEABLE); 3117 splx(s); 3118} 3119 3120/* 3121 * pmap_page_protect: 3122 * 3123 * Lower the permission for all mappings to a given page. 3124 */ 3125void 3126pmap_page_protect(vm_page_t m, vm_prot_t prot) 3127{ 3128 if ((prot & VM_PROT_WRITE) == 0) { 3129 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3130 pmap_changebit(m, PG_RW, FALSE); 3131 } else { 3132 pmap_remove_all(m); 3133 } 3134 } 3135} 3136 3137vm_offset_t 3138pmap_phys_address(ppn) 3139 int ppn; 3140{ 3141 return (i386_ptob(ppn)); 3142} 3143 3144/* 3145 * pmap_ts_referenced: 3146 * 3147 * Return a count of reference bits for a page, clearing those bits. 3148 * It is not necessary for every reference bit to be cleared, but it 3149 * is necessary that 0 only be returned when there are truly no 3150 * reference bits set. 3151 * 3152 * XXX: The exact number of bits to check and clear is a matter that 3153 * should be tested and standardized at some point in the future for 3154 * optimal aging of shared pages. 3155 */ 3156int 3157pmap_ts_referenced(vm_page_t m) 3158{ 3159 register pv_entry_t pv, pvf, pvn; 3160 pt_entry_t *pte; 3161 int s; 3162 int rtval = 0; 3163 3164 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3165 return (rtval); 3166 3167 s = splvm(); 3168 3169 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3170 3171 pvf = pv; 3172 3173 do { 3174 pvn = TAILQ_NEXT(pv, pv_list); 3175 3176 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3177 3178 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3179 3180 if (!pmap_track_modified(pv->pv_va)) 3181 continue; 3182 3183 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3184 3185 if (pte && (*pte & PG_A)) { 3186 *pte &= ~PG_A; 3187 3188 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3189 3190 rtval++; 3191 if (rtval > 4) { 3192 break; 3193 } 3194 } 3195 } while ((pv = pvn) != NULL && pv != pvf); 3196 } 3197 splx(s); 3198 3199 return (rtval); 3200} 3201 3202/* 3203 * pmap_is_modified: 3204 * 3205 * Return whether or not the specified physical page was modified 3206 * in any physical maps. 3207 */ 3208boolean_t 3209pmap_is_modified(vm_page_t m) 3210{ 3211 return pmap_testbit(m, PG_M); 3212} 3213 3214/* 3215 * Clear the modify bits on the specified physical page. 3216 */ 3217void 3218pmap_clear_modify(vm_page_t m) 3219{ 3220 pmap_changebit(m, PG_M, FALSE); 3221} 3222 3223/* 3224 * pmap_clear_reference: 3225 * 3226 * Clear the reference bit on the specified physical page. 3227 */ 3228void 3229pmap_clear_reference(vm_page_t m) 3230{ 3231 pmap_changebit(m, PG_A, FALSE); 3232} 3233 3234/* 3235 * Miscellaneous support routines follow 3236 */ 3237 3238static void 3239i386_protection_init() 3240{ 3241 register int *kp, prot; 3242 3243 kp = protection_codes; 3244 for (prot = 0; prot < 8; prot++) { 3245 switch (prot) { 3246 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3247 /* 3248 * Read access is also 0. There isn't any execute bit, 3249 * so just make it readable. 3250 */ 3251 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3252 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3253 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3254 *kp++ = 0; 3255 break; 3256 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3257 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3258 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3259 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3260 *kp++ = PG_RW; 3261 break; 3262 } 3263 } 3264} 3265 3266/* 3267 * Map a set of physical memory pages into the kernel virtual 3268 * address space. Return a pointer to where it is mapped. This 3269 * routine is intended to be used for mapping device memory, 3270 * NOT real memory. 3271 */ 3272void * 3273pmap_mapdev(pa, size) 3274 vm_offset_t pa; 3275 vm_size_t size; 3276{ 3277 vm_offset_t va, tmpva, offset; 3278 pt_entry_t *pte; 3279 3280 offset = pa & PAGE_MASK; 3281 size = roundup(offset + size, PAGE_SIZE); 3282 3283 GIANT_REQUIRED; 3284 3285 va = kmem_alloc_pageable(kernel_map, size); 3286 if (!va) 3287 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3288 3289 pa = pa & PG_FRAME; 3290 for (tmpva = va; size > 0; ) { 3291 pte = vtopte(tmpva); 3292 *pte = pa | PG_RW | PG_V | pgeflag; 3293 size -= PAGE_SIZE; 3294 tmpva += PAGE_SIZE; 3295 pa += PAGE_SIZE; 3296 } 3297 pmap_invalidate_range(kernel_pmap, va, tmpva); 3298 return ((void *)(va + offset)); 3299} 3300 3301void 3302pmap_unmapdev(va, size) 3303 vm_offset_t va; 3304 vm_size_t size; 3305{ 3306 vm_offset_t base, offset, tmpva; 3307 pt_entry_t *pte; 3308 3309 base = va & PG_FRAME; 3310 offset = va & PAGE_MASK; 3311 size = roundup(offset + size, PAGE_SIZE); 3312 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE) { 3313 pte = vtopte(tmpva); 3314 *pte = 0; 3315 } 3316 pmap_invalidate_range(kernel_pmap, va, tmpva); 3317 kmem_free(kernel_map, base, size); 3318} 3319 3320/* 3321 * perform the pmap work for mincore 3322 */ 3323int 3324pmap_mincore(pmap, addr) 3325 pmap_t pmap; 3326 vm_offset_t addr; 3327{ 3328 pt_entry_t *ptep, pte; 3329 vm_page_t m; 3330 int val = 0; 3331 3332 ptep = pmap_pte(pmap, addr); 3333 if (ptep == 0) { 3334 return 0; 3335 } 3336 3337 if ((pte = *ptep) != 0) { 3338 vm_offset_t pa; 3339 3340 val = MINCORE_INCORE; 3341 if ((pte & PG_MANAGED) == 0) 3342 return val; 3343 3344 pa = pte & PG_FRAME; 3345 3346 m = PHYS_TO_VM_PAGE(pa); 3347 3348 /* 3349 * Modified by us 3350 */ 3351 if (pte & PG_M) 3352 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3353 /* 3354 * Modified by someone 3355 */ 3356 else if (m->dirty || pmap_is_modified(m)) 3357 val |= MINCORE_MODIFIED_OTHER; 3358 /* 3359 * Referenced by us 3360 */ 3361 if (pte & PG_A) 3362 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3363 3364 /* 3365 * Referenced by someone 3366 */ 3367 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3368 val |= MINCORE_REFERENCED_OTHER; 3369 vm_page_flag_set(m, PG_REFERENCED); 3370 } 3371 } 3372 return val; 3373} 3374 3375void 3376pmap_activate(struct thread *td) 3377{ 3378 struct proc *p = td->td_proc; 3379 pmap_t pmap; 3380 u_int32_t cr3; 3381 3382 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3383#if defined(SMP) 3384 pmap->pm_active |= PCPU_GET(cpumask); 3385#else 3386 pmap->pm_active |= 1; 3387#endif 3388 cr3 = vtophys(pmap->pm_pdir); 3389 /* XXXKSE this is wrong. 3390 * pmap_activate is for the current thread on the current cpu 3391 */ 3392 if (p->p_flag & P_KSES) { 3393 /* Make sure all other cr3 entries are updated. */ 3394 /* what if they are running? XXXKSE (maybe abort them) */ 3395 FOREACH_THREAD_IN_PROC(p, td) { 3396 td->td_pcb->pcb_cr3 = cr3; 3397 } 3398 } else { 3399 td->td_pcb->pcb_cr3 = cr3; 3400 } 3401 load_cr3(cr3); 3402#ifdef SWTCH_OPTIM_STATS 3403 tlb_flush_count++; 3404#endif 3405} 3406 3407vm_offset_t 3408pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3409{ 3410 3411 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3412 return addr; 3413 } 3414 3415 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3416 return addr; 3417} 3418 3419 3420#if defined(PMAP_DEBUG) 3421pmap_pid_dump(int pid) 3422{ 3423 pmap_t pmap; 3424 struct proc *p; 3425 int npte = 0; 3426 int index; 3427 3428 sx_slock(&allproc_lock); 3429 LIST_FOREACH(p, &allproc, p_list) { 3430 if (p->p_pid != pid) 3431 continue; 3432 3433 if (p->p_vmspace) { 3434 int i,j; 3435 index = 0; 3436 pmap = vmspace_pmap(p->p_vmspace); 3437 for (i = 0; i < NPDEPG; i++) { 3438 pd_entry_t *pde; 3439 pt_entry_t *pte; 3440 vm_offset_t base = i << PDRSHIFT; 3441 3442 pde = &pmap->pm_pdir[i]; 3443 if (pde && pmap_pde_v(pde)) { 3444 for (j = 0; j < NPTEPG; j++) { 3445 vm_offset_t va = base + (j << PAGE_SHIFT); 3446 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3447 if (index) { 3448 index = 0; 3449 printf("\n"); 3450 } 3451 sx_sunlock(&allproc_lock); 3452 return npte; 3453 } 3454 pte = pmap_pte_quick(pmap, va); 3455 if (pte && pmap_pte_v(pte)) { 3456 pt_entry_t pa; 3457 vm_page_t m; 3458 pa = *pte; 3459 m = PHYS_TO_VM_PAGE(pa); 3460 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3461 va, pa, m->hold_count, m->wire_count, m->flags); 3462 npte++; 3463 index++; 3464 if (index >= 2) { 3465 index = 0; 3466 printf("\n"); 3467 } else { 3468 printf(" "); 3469 } 3470 } 3471 } 3472 } 3473 } 3474 } 3475 } 3476 sx_sunlock(&allproc_lock); 3477 return npte; 3478} 3479#endif 3480 3481#if defined(DEBUG) 3482 3483static void pads(pmap_t pm); 3484void pmap_pvdump(vm_offset_t pa); 3485 3486/* print address space of pmap*/ 3487static void 3488pads(pm) 3489 pmap_t pm; 3490{ 3491 int i, j; 3492 vm_offset_t va; 3493 pt_entry_t *ptep; 3494 3495 if (pm == kernel_pmap) 3496 return; 3497 for (i = 0; i < NPDEPG; i++) 3498 if (pm->pm_pdir[i]) 3499 for (j = 0; j < NPTEPG; j++) { 3500 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3501 if (pm == kernel_pmap && va < KERNBASE) 3502 continue; 3503 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3504 continue; 3505 ptep = pmap_pte_quick(pm, va); 3506 if (pmap_pte_v(ptep)) 3507 printf("%x:%x ", va, *ptep); 3508 }; 3509 3510} 3511 3512void 3513pmap_pvdump(pa) 3514 vm_offset_t pa; 3515{ 3516 pv_entry_t pv; 3517 vm_page_t m; 3518 3519 printf("pa %x", pa); 3520 m = PHYS_TO_VM_PAGE(pa); 3521 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3522 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3523 pads(pv->pv_pmap); 3524 } 3525 printf(" "); 3526} 3527#endif 3528