pmap.c revision 106567
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 106567 2002-11-07 18:33:55Z 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 void pmap_remove_all(vm_page_t m); 207static vm_page_t pmap_enter_quick(pmap_t pmap, vm_offset_t va, 208 vm_page_t m, vm_page_t mpte); 209static int pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t sva); 210static void pmap_remove_page(struct pmap *pmap, vm_offset_t va); 211static int pmap_remove_entry(struct pmap *pmap, vm_page_t m, 212 vm_offset_t va); 213static boolean_t pmap_testbit(vm_page_t m, int bit); 214static void pmap_insert_entry(pmap_t pmap, vm_offset_t va, 215 vm_page_t mpte, vm_page_t m); 216 217static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va); 218 219static int pmap_release_free_page(pmap_t pmap, vm_page_t p); 220static vm_page_t _pmap_allocpte(pmap_t pmap, unsigned ptepindex); 221static pt_entry_t *pmap_pte_quick(pmap_t pmap, vm_offset_t va); 222static vm_page_t pmap_page_lookup(vm_object_t object, vm_pindex_t pindex); 223static int pmap_unuse_pt(pmap_t, vm_offset_t, vm_page_t); 224static vm_offset_t pmap_kmem_choose(vm_offset_t addr); 225static void *pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait); 226 227static pd_entry_t pdir4mb; 228 229/* 230 * Routine: pmap_pte 231 * Function: 232 * Extract the page table entry associated 233 * with the given map/virtual_address pair. 234 */ 235 236PMAP_INLINE pt_entry_t * 237pmap_pte(pmap, va) 238 register pmap_t pmap; 239 vm_offset_t va; 240{ 241 pd_entry_t *pdeaddr; 242 243 if (pmap) { 244 pdeaddr = pmap_pde(pmap, va); 245 if (*pdeaddr & PG_PS) 246 return pdeaddr; 247 if (*pdeaddr) { 248 return get_ptbase(pmap) + i386_btop(va); 249 } 250 } 251 return (0); 252} 253 254/* 255 * Move the kernel virtual free pointer to the next 256 * 4MB. This is used to help improve performance 257 * by using a large (4MB) page for much of the kernel 258 * (.text, .data, .bss) 259 */ 260static vm_offset_t 261pmap_kmem_choose(vm_offset_t addr) 262{ 263 vm_offset_t newaddr = addr; 264 265#ifndef DISABLE_PSE 266 if (cpu_feature & CPUID_PSE) 267 newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 268#endif 269 return newaddr; 270} 271 272/* 273 * Bootstrap the system enough to run with virtual memory. 274 * 275 * On the i386 this is called after mapping has already been enabled 276 * and just syncs the pmap module with what has already been done. 277 * [We can't call it easily with mapping off since the kernel is not 278 * mapped with PA == VA, hence we would have to relocate every address 279 * from the linked base (virtual) address "KERNBASE" to the actual 280 * (physical) address starting relative to 0] 281 */ 282void 283pmap_bootstrap(firstaddr, loadaddr) 284 vm_offset_t firstaddr; 285 vm_offset_t loadaddr; 286{ 287 vm_offset_t va; 288 pt_entry_t *pte; 289 int i; 290 291 avail_start = firstaddr; 292 293 /* 294 * XXX The calculation of virtual_avail is wrong. It's NKPT*PAGE_SIZE too 295 * large. It should instead be correctly calculated in locore.s and 296 * not based on 'first' (which is a physical address, not a virtual 297 * address, for the start of unused physical memory). The kernel 298 * page tables are NOT double mapped and thus should not be included 299 * in this calculation. 300 */ 301 virtual_avail = (vm_offset_t) KERNBASE + firstaddr; 302 virtual_avail = pmap_kmem_choose(virtual_avail); 303 304 virtual_end = VM_MAX_KERNEL_ADDRESS; 305 306 /* 307 * Initialize protection array. 308 */ 309 i386_protection_init(); 310 311 /* 312 * Initialize the kernel pmap (which is statically allocated). 313 */ 314 kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD); 315 kernel_pmap->pm_active = -1; /* don't allow deactivation */ 316 TAILQ_INIT(&kernel_pmap->pm_pvlist); 317 LIST_INIT(&allpmaps); 318 LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list); 319 nkpt = NKPT; 320 321 /* 322 * Reserve some special page table entries/VA space for temporary 323 * mapping of pages. 324 */ 325#define SYSMAP(c, p, v, n) \ 326 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n); 327 328 va = virtual_avail; 329 pte = (pt_entry_t *) pmap_pte(kernel_pmap, va); 330 331 /* 332 * CMAP1/CMAP2 are used for zeroing and copying pages. 333 * CMAP3 is used for the idle process page zeroing. 334 */ 335 SYSMAP(caddr_t, CMAP1, CADDR1, 1) 336 SYSMAP(caddr_t, CMAP2, CADDR2, 1) 337 SYSMAP(caddr_t, CMAP3, CADDR3, 1) 338 339 /* 340 * Crashdump maps. 341 */ 342 SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS); 343 344 /* 345 * ptvmmap is used for reading arbitrary physical pages via /dev/mem. 346 * XXX ptmmap is not used. 347 */ 348 SYSMAP(caddr_t, ptmmap, ptvmmap, 1) 349 350 /* 351 * msgbufp is used to map the system message buffer. 352 * XXX msgbufmap is not used. 353 */ 354 SYSMAP(struct msgbuf *, msgbufmap, msgbufp, 355 atop(round_page(MSGBUF_SIZE))) 356 357 /* 358 * ptemap is used for pmap_pte_quick 359 */ 360 SYSMAP(pt_entry_t *, PMAP1, PADDR1, 1); 361 362 virtual_avail = va; 363 364 *CMAP1 = *CMAP2 = 0; 365 for (i = 0; i < NKPT; i++) 366 PTD[i] = 0; 367 368 pgeflag = 0; 369#ifndef DISABLE_PG_G 370 if (cpu_feature & CPUID_PGE) 371 pgeflag = PG_G; 372#endif 373 374/* 375 * Initialize the 4MB page size flag 376 */ 377 pseflag = 0; 378/* 379 * The 4MB page version of the initial 380 * kernel page mapping. 381 */ 382 pdir4mb = 0; 383 384#ifndef DISABLE_PSE 385 if (cpu_feature & CPUID_PSE) { 386 pd_entry_t ptditmp; 387 /* 388 * Note that we have enabled PSE mode 389 */ 390 pseflag = PG_PS; 391 ptditmp = *(PTmap + i386_btop(KERNBASE)); 392 ptditmp &= ~(NBPDR - 1); 393 ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag; 394 pdir4mb = ptditmp; 395 } 396#endif 397#ifndef SMP 398 /* 399 * Turn on PGE/PSE. SMP does this later on since the 400 * 4K page tables are required for AP boot (for now). 401 * XXX fixme. 402 */ 403 pmap_set_opt(); 404#endif 405#ifdef SMP 406 if (cpu_apic_address == 0) 407 panic("pmap_bootstrap: no local apic! (non-SMP hardware?)"); 408 409 /* local apic is mapped on last page */ 410 SMPpt[NPTEPG - 1] = (pt_entry_t)(PG_V | PG_RW | PG_N | pgeflag | 411 (cpu_apic_address & PG_FRAME)); 412#endif 413 invltlb(); 414} 415 416/* 417 * Enable 4MB page mode for MP startup. Turn on PG_G support. 418 * BSP will run this after all the AP's have started up. 419 */ 420void 421pmap_set_opt(void) 422{ 423 pt_entry_t *pte; 424 vm_offset_t va, endva; 425 426 if (pgeflag && (cpu_feature & CPUID_PGE)) { 427 load_cr4(rcr4() | CR4_PGE); 428 invltlb(); /* Insurance */ 429 } 430#ifndef DISABLE_PSE 431 if (pseflag && (cpu_feature & CPUID_PSE)) { 432 load_cr4(rcr4() | CR4_PSE); 433 invltlb(); /* Insurance */ 434 } 435#endif 436 if (PCPU_GET(cpuid) == 0) { 437#ifndef DISABLE_PSE 438 if (pdir4mb) { 439 kernel_pmap->pm_pdir[KPTDI] = PTD[KPTDI] = pdir4mb; 440 invltlb(); /* Insurance */ 441 } 442#endif 443 if (pgeflag) { 444 /* Turn on PG_G for text, data, bss pages. */ 445 va = (vm_offset_t)btext; 446#ifndef DISABLE_PSE 447 if (pseflag && (cpu_feature & CPUID_PSE)) { 448 if (va < KERNBASE + (1 << PDRSHIFT)) 449 va = KERNBASE + (1 << PDRSHIFT); 450 } 451#endif 452 endva = KERNBASE + KERNend; 453 while (va < endva) { 454 pte = vtopte(va); 455 if (*pte) 456 *pte |= pgeflag; 457 va += PAGE_SIZE; 458 } 459 invltlb(); /* Insurance */ 460 } 461 /* 462 * We do not need to broadcast the invltlb here, because 463 * each AP does it the moment it is released from the boot 464 * lock. See ap_init(). 465 */ 466 } 467} 468 469static void * 470pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait) 471{ 472 *flags = UMA_SLAB_PRIV; 473 return (void *)kmem_alloc(kernel_map, bytes); 474} 475 476/* 477 * Initialize the pmap module. 478 * Called by vm_init, to initialize any structures that the pmap 479 * system needs to map virtual memory. 480 * pmap_init has been enhanced to support in a fairly consistant 481 * way, discontiguous physical memory. 482 */ 483void 484pmap_init(phys_start, phys_end) 485 vm_offset_t phys_start, phys_end; 486{ 487 int i; 488 int initial_pvs; 489 490 /* 491 * object for kernel page table pages 492 */ 493 kptobj = vm_object_allocate(OBJT_DEFAULT, NKPDE); 494 495 /* 496 * Allocate memory for random pmap data structures. Includes the 497 * pv_head_table. 498 */ 499 500 for(i = 0; i < vm_page_array_size; i++) { 501 vm_page_t m; 502 503 m = &vm_page_array[i]; 504 TAILQ_INIT(&m->md.pv_list); 505 m->md.pv_list_count = 0; 506 } 507 508 /* 509 * init the pv free list 510 */ 511 initial_pvs = vm_page_array_size; 512 if (initial_pvs < MINPV) 513 initial_pvs = MINPV; 514 pvzone = uma_zcreate("PV ENTRY", sizeof (struct pv_entry), NULL, NULL, 515 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM); 516 uma_zone_set_allocf(pvzone, pmap_allocf); 517 uma_prealloc(pvzone, initial_pvs); 518 519 /* 520 * Now it is safe to enable pv_table recording. 521 */ 522 pmap_initialized = TRUE; 523} 524 525/* 526 * Initialize the address space (zone) for the pv_entries. Set a 527 * high water mark so that the system can recover from excessive 528 * numbers of pv entries. 529 */ 530void 531pmap_init2() 532{ 533 int shpgperproc = PMAP_SHPGPERPROC; 534 535 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc); 536 pv_entry_max = shpgperproc * maxproc + vm_page_array_size; 537 TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max); 538 pv_entry_high_water = 9 * (pv_entry_max / 10); 539 uma_zone_set_obj(pvzone, &pvzone_obj, pv_entry_max); 540} 541 542 543/*************************************************** 544 * Low level helper routines..... 545 ***************************************************/ 546 547#if defined(PMAP_DIAGNOSTIC) 548 549/* 550 * This code checks for non-writeable/modified pages. 551 * This should be an invalid condition. 552 */ 553static int 554pmap_nw_modified(pt_entry_t ptea) 555{ 556 int pte; 557 558 pte = (int) ptea; 559 560 if ((pte & (PG_M|PG_RW)) == PG_M) 561 return 1; 562 else 563 return 0; 564} 565#endif 566 567 568/* 569 * this routine defines the region(s) of memory that should 570 * not be tested for the modified bit. 571 */ 572static PMAP_INLINE int 573pmap_track_modified(vm_offset_t va) 574{ 575 if ((va < kmi.clean_sva) || (va >= kmi.clean_eva)) 576 return 1; 577 else 578 return 0; 579} 580 581#ifdef I386_CPU 582/* 583 * i386 only has "invalidate everything" and no SMP to worry about. 584 */ 585PMAP_INLINE void 586pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 587{ 588 589 if (pmap == kernel_pmap || pmap->pm_active) 590 invltlb(); 591} 592 593PMAP_INLINE void 594pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 595{ 596 597 if (pmap == kernel_pmap || pmap->pm_active) 598 invltlb(); 599} 600 601PMAP_INLINE void 602pmap_invalidate_all(pmap_t pmap) 603{ 604 605 if (pmap == kernel_pmap || pmap->pm_active) 606 invltlb(); 607} 608#else /* !I386_CPU */ 609#ifdef SMP 610/* 611 * For SMP, these functions have to use the IPI mechanism for coherence. 612 */ 613void 614pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 615{ 616 u_int cpumask; 617 u_int other_cpus; 618 619 critical_enter(); 620 /* 621 * We need to disable interrupt preemption but MUST NOT have 622 * interrupts disabled here. 623 * XXX we may need to hold schedlock to get a coherent pm_active 624 */ 625 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 626 invlpg(va); 627 smp_invlpg(va); 628 } else { 629 cpumask = PCPU_GET(cpumask); 630 other_cpus = PCPU_GET(other_cpus); 631 if (pmap->pm_active & cpumask) 632 invlpg(va); 633 if (pmap->pm_active & other_cpus) 634 smp_masked_invlpg(pmap->pm_active & other_cpus, va); 635 } 636 critical_exit(); 637} 638 639void 640pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 641{ 642 u_int cpumask; 643 u_int other_cpus; 644 vm_offset_t addr; 645 646 critical_enter(); 647 /* 648 * We need to disable interrupt preemption but MUST NOT have 649 * interrupts disabled here. 650 * XXX we may need to hold schedlock to get a coherent pm_active 651 */ 652 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 653 for (addr = sva; addr < eva; addr += PAGE_SIZE) 654 invlpg(addr); 655 smp_invlpg_range(sva, eva); 656 } else { 657 cpumask = PCPU_GET(cpumask); 658 other_cpus = PCPU_GET(other_cpus); 659 if (pmap->pm_active & cpumask) 660 for (addr = sva; addr < eva; addr += PAGE_SIZE) 661 invlpg(addr); 662 if (pmap->pm_active & other_cpus) 663 smp_masked_invlpg_range(pmap->pm_active & other_cpus, 664 sva, eva); 665 } 666 critical_exit(); 667} 668 669void 670pmap_invalidate_all(pmap_t pmap) 671{ 672 u_int cpumask; 673 u_int other_cpus; 674 675#ifdef SWTCH_OPTIM_STATS 676 tlb_flush_count++; 677#endif 678 critical_enter(); 679 /* 680 * We need to disable interrupt preemption but MUST NOT have 681 * interrupts disabled here. 682 * XXX we may need to hold schedlock to get a coherent pm_active 683 */ 684 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 685 invltlb(); 686 smp_invltlb(); 687 } else { 688 cpumask = PCPU_GET(cpumask); 689 other_cpus = PCPU_GET(other_cpus); 690 if (pmap->pm_active & cpumask) 691 invltlb(); 692 if (pmap->pm_active & other_cpus) 693 smp_masked_invltlb(pmap->pm_active & other_cpus); 694 } 695 critical_exit(); 696} 697#else /* !SMP */ 698/* 699 * Normal, non-SMP, 486+ invalidation functions. 700 * We inline these within pmap.c for speed. 701 */ 702PMAP_INLINE void 703pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 704{ 705 706 if (pmap == kernel_pmap || pmap->pm_active) 707 invlpg(va); 708} 709 710PMAP_INLINE void 711pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 712{ 713 vm_offset_t addr; 714 715 if (pmap == kernel_pmap || pmap->pm_active) 716 for (addr = sva; addr < eva; addr += PAGE_SIZE) 717 invlpg(addr); 718} 719 720PMAP_INLINE void 721pmap_invalidate_all(pmap_t pmap) 722{ 723 724 if (pmap == kernel_pmap || pmap->pm_active) 725 invltlb(); 726} 727#endif /* !SMP */ 728#endif /* !I386_CPU */ 729 730/* 731 * Return an address which is the base of the Virtual mapping of 732 * all the PTEs for the given pmap. Note this doesn't say that 733 * all the PTEs will be present or that the pages there are valid. 734 * The PTEs are made available by the recursive mapping trick. 735 * It will map in the alternate PTE space if needed. 736 */ 737static pt_entry_t * 738get_ptbase(pmap) 739 pmap_t pmap; 740{ 741 pd_entry_t frame; 742 743 /* are we current address space or kernel? */ 744 if (pmap == kernel_pmap) 745 return PTmap; 746 frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 747 if (frame == (PTDpde & PG_FRAME)) 748 return PTmap; 749 /* otherwise, we are alternate address space */ 750 if (frame != (APTDpde & PG_FRAME)) { 751 APTDpde = (pd_entry_t) (frame | PG_RW | PG_V); 752 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 753 } 754 return APTmap; 755} 756 757/* 758 * Super fast pmap_pte routine best used when scanning 759 * the pv lists. This eliminates many coarse-grained 760 * invltlb calls. Note that many of the pv list 761 * scans are across different pmaps. It is very wasteful 762 * to do an entire invltlb for checking a single mapping. 763 */ 764 765static pt_entry_t * 766pmap_pte_quick(pmap, va) 767 register pmap_t pmap; 768 vm_offset_t va; 769{ 770 pd_entry_t pde, newpf; 771 pde = pmap->pm_pdir[va >> PDRSHIFT]; 772 if (pde != 0) { 773 pd_entry_t frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 774 unsigned index = i386_btop(va); 775 /* are we current address space or kernel? */ 776 if (pmap == kernel_pmap || frame == (PTDpde & PG_FRAME)) 777 return PTmap + index; 778 newpf = pde & PG_FRAME; 779 if (((*PMAP1) & PG_FRAME) != newpf) { 780 *PMAP1 = newpf | PG_RW | PG_V; 781 pmap_invalidate_page(kernel_pmap, (vm_offset_t)PADDR1); 782 } 783 return PADDR1 + (index & (NPTEPG - 1)); 784 } 785 return (0); 786} 787 788/* 789 * Routine: pmap_extract 790 * Function: 791 * Extract the physical page address associated 792 * with the given map/virtual_address pair. 793 */ 794vm_offset_t 795pmap_extract(pmap, va) 796 register pmap_t pmap; 797 vm_offset_t va; 798{ 799 vm_offset_t rtval; /* XXX FIXME */ 800 vm_offset_t pdirindex; 801 802 if (pmap == 0) 803 return 0; 804 pdirindex = va >> PDRSHIFT; 805 rtval = pmap->pm_pdir[pdirindex]; 806 if (rtval != 0) { 807 pt_entry_t *pte; 808 if ((rtval & PG_PS) != 0) { 809 rtval &= ~(NBPDR - 1); 810 rtval |= va & (NBPDR - 1); 811 return rtval; 812 } 813 pte = get_ptbase(pmap) + i386_btop(va); 814 rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); 815 return rtval; 816 } 817 return 0; 818 819} 820 821/*************************************************** 822 * Low level mapping routines..... 823 ***************************************************/ 824 825/* 826 * Add a wired page to the kva. 827 * Note: not SMP coherent. 828 */ 829PMAP_INLINE void 830pmap_kenter(vm_offset_t va, vm_offset_t pa) 831{ 832 pt_entry_t *pte; 833 834 pte = vtopte(va); 835 *pte = pa | PG_RW | PG_V | pgeflag; 836} 837 838/* 839 * Remove a page from the kernel pagetables. 840 * Note: not SMP coherent. 841 */ 842PMAP_INLINE void 843pmap_kremove(vm_offset_t va) 844{ 845 pt_entry_t *pte; 846 847 pte = vtopte(va); 848 *pte = 0; 849} 850 851/* 852 * Used to map a range of physical addresses into kernel 853 * virtual address space. 854 * 855 * The value passed in '*virt' is a suggested virtual address for 856 * the mapping. Architectures which can support a direct-mapped 857 * physical to virtual region can return the appropriate address 858 * within that region, leaving '*virt' unchanged. Other 859 * architectures should map the pages starting at '*virt' and 860 * update '*virt' with the first usable address after the mapped 861 * region. 862 */ 863vm_offset_t 864pmap_map(vm_offset_t *virt, vm_offset_t start, vm_offset_t end, int prot) 865{ 866 vm_offset_t va, sva; 867 868 va = sva = *virt; 869 while (start < end) { 870 pmap_kenter(va, start); 871 va += PAGE_SIZE; 872 start += PAGE_SIZE; 873 } 874 pmap_invalidate_range(kernel_pmap, sva, va); 875 *virt = va; 876 return (sva); 877} 878 879 880/* 881 * Add a list of wired pages to the kva 882 * this routine is only used for temporary 883 * kernel mappings that do not need to have 884 * page modification or references recorded. 885 * Note that old mappings are simply written 886 * over. The page *must* be wired. 887 * Note: SMP coherent. Uses a ranged shootdown IPI. 888 */ 889void 890pmap_qenter(vm_offset_t sva, vm_page_t *m, int count) 891{ 892 vm_offset_t va; 893 894 va = sva; 895 while (count-- > 0) { 896 pmap_kenter(va, VM_PAGE_TO_PHYS(*m)); 897 va += PAGE_SIZE; 898 m++; 899 } 900 pmap_invalidate_range(kernel_pmap, sva, va); 901} 902 903/* 904 * This routine tears out page mappings from the 905 * kernel -- it is meant only for temporary mappings. 906 * Note: SMP coherent. Uses a ranged shootdown IPI. 907 */ 908void 909pmap_qremove(vm_offset_t sva, int count) 910{ 911 vm_offset_t va; 912 913 va = sva; 914 while (count-- > 0) { 915 pmap_kremove(va); 916 va += PAGE_SIZE; 917 } 918 pmap_invalidate_range(kernel_pmap, sva, va); 919} 920 921static vm_page_t 922pmap_page_lookup(vm_object_t object, vm_pindex_t pindex) 923{ 924 vm_page_t m; 925 926retry: 927 m = vm_page_lookup(object, pindex); 928 if (m != NULL) { 929 vm_page_lock_queues(); 930 if (vm_page_sleep_if_busy(m, FALSE, "pplookp")) 931 goto retry; 932 vm_page_unlock_queues(); 933 } 934 return m; 935} 936 937#ifndef KSTACK_MAX_PAGES 938#define KSTACK_MAX_PAGES 32 939#endif 940 941/* 942 * Create the kernel stack (including pcb for i386) for a new thread. 943 * This routine directly affects the fork perf for a process and 944 * create performance for a thread. 945 */ 946void 947pmap_new_thread(struct thread *td, int pages) 948{ 949 int i; 950 vm_page_t ma[KSTACK_MAX_PAGES]; 951 vm_object_t ksobj; 952 vm_page_t m; 953 vm_offset_t ks; 954 955 /* Bounds check */ 956 if (pages <= 1) 957 pages = KSTACK_PAGES; 958 else if (pages > KSTACK_MAX_PAGES) 959 pages = KSTACK_MAX_PAGES; 960 961 /* 962 * allocate object for the kstack 963 */ 964 ksobj = vm_object_allocate(OBJT_DEFAULT, pages); 965 td->td_kstack_obj = ksobj; 966 967 /* get a kernel virtual address for the kstack for this thread */ 968#ifdef KSTACK_GUARD 969 ks = kmem_alloc_nofault(kernel_map, (pages + 1) * PAGE_SIZE); 970 if (ks == 0) 971 panic("pmap_new_thread: kstack allocation failed"); 972 if (*vtopte(ks) != 0) 973 pmap_qremove(ks, 1); 974 ks += PAGE_SIZE; 975 td->td_kstack = ks; 976#else 977 /* get a kernel virtual address for the kstack for this thread */ 978 ks = kmem_alloc_nofault(kernel_map, pages * PAGE_SIZE); 979 if (ks == 0) 980 panic("pmap_new_thread: kstack allocation failed"); 981 td->td_kstack = ks; 982#endif 983 /* 984 * Knowing the number of pages allocated is useful when you 985 * want to deallocate them. 986 */ 987 td->td_kstack_pages = pages; 988 989 /* 990 * For the length of the stack, link in a real page of ram for each 991 * page of stack. 992 */ 993 for (i = 0; i < pages; i++) { 994 /* 995 * Get a kernel stack page 996 */ 997 m = vm_page_grab(ksobj, i, 998 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED); 999 ma[i] = m; 1000 1001 vm_page_wakeup(m); 1002 vm_page_flag_clear(m, PG_ZERO); 1003 m->valid = VM_PAGE_BITS_ALL; 1004 } 1005 pmap_qenter(ks, ma, pages); 1006} 1007 1008/* 1009 * Dispose the kernel stack for a thread that has exited. 1010 * This routine directly impacts the exit perf of a process and thread. 1011 */ 1012void 1013pmap_dispose_thread(td) 1014 struct thread *td; 1015{ 1016 int i; 1017 int pages; 1018 vm_object_t ksobj; 1019 vm_offset_t ks; 1020 vm_page_t m; 1021 1022 pages = td->td_kstack_pages; 1023 ksobj = td->td_kstack_obj; 1024 ks = td->td_kstack; 1025 pmap_qremove(ks, pages); 1026 for (i = 0; i < pages; i++) { 1027 m = vm_page_lookup(ksobj, i); 1028 if (m == NULL) 1029 panic("pmap_dispose_thread: kstack already missing?"); 1030 vm_page_lock_queues(); 1031 vm_page_busy(m); 1032 vm_page_unwire(m, 0); 1033 vm_page_free(m); 1034 vm_page_unlock_queues(); 1035 } 1036 /* 1037 * Free the space that this stack was mapped to in the kernel 1038 * address map. 1039 */ 1040#ifdef KSTACK_GUARD 1041 kmem_free(kernel_map, ks - PAGE_SIZE, (pages + 1) * PAGE_SIZE); 1042#else 1043 kmem_free(kernel_map, ks, pages * PAGE_SIZE); 1044#endif 1045 vm_object_deallocate(ksobj); 1046} 1047 1048/* 1049 * Set up a variable sized alternate kstack. Though it may look MI, it may 1050 * need to be different on certain arches like ia64. 1051 */ 1052void 1053pmap_new_altkstack(struct thread *td, int pages) 1054{ 1055 /* shuffle the original stack */ 1056 td->td_altkstack_obj = td->td_kstack_obj; 1057 td->td_altkstack = td->td_kstack; 1058 td->td_altkstack_pages = td->td_kstack_pages; 1059 1060 pmap_new_thread(td, pages); 1061} 1062 1063void 1064pmap_dispose_altkstack(td) 1065 struct thread *td; 1066{ 1067 pmap_dispose_thread(td); 1068 1069 /* restore the original kstack */ 1070 td->td_kstack = td->td_altkstack; 1071 td->td_kstack_obj = td->td_altkstack_obj; 1072 td->td_kstack_pages = td->td_altkstack_pages; 1073 td->td_altkstack = 0; 1074 td->td_altkstack_obj = NULL; 1075 td->td_altkstack_pages = 0; 1076} 1077 1078/* 1079 * Allow the Kernel stack for a thread to be prejudicially paged out. 1080 */ 1081void 1082pmap_swapout_thread(td) 1083 struct thread *td; 1084{ 1085 int i; 1086 int pages; 1087 vm_object_t ksobj; 1088 vm_offset_t ks; 1089 vm_page_t m; 1090 1091 pages = td->td_kstack_pages; 1092 ksobj = td->td_kstack_obj; 1093 ks = td->td_kstack; 1094 pmap_qremove(ks, pages); 1095 for (i = 0; i < pages; i++) { 1096 m = vm_page_lookup(ksobj, i); 1097 if (m == NULL) 1098 panic("pmap_swapout_thread: kstack already missing?"); 1099 vm_page_lock_queues(); 1100 vm_page_dirty(m); 1101 vm_page_unwire(m, 0); 1102 vm_page_unlock_queues(); 1103 } 1104} 1105 1106/* 1107 * Bring the kernel stack for a specified thread back in. 1108 */ 1109void 1110pmap_swapin_thread(td) 1111 struct thread *td; 1112{ 1113 int i, rv; 1114 int pages; 1115 vm_page_t ma[KSTACK_MAX_PAGES]; 1116 vm_object_t ksobj; 1117 vm_offset_t ks; 1118 vm_page_t m; 1119 1120 pages = td->td_kstack_pages; 1121 ksobj = td->td_kstack_obj; 1122 ks = td->td_kstack; 1123 for (i = 0; i < pages; i++) { 1124 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1125 if (m->valid != VM_PAGE_BITS_ALL) { 1126 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1127 if (rv != VM_PAGER_OK) 1128 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1129 m = vm_page_lookup(ksobj, i); 1130 m->valid = VM_PAGE_BITS_ALL; 1131 } 1132 ma[i] = m; 1133 vm_page_lock_queues(); 1134 vm_page_wire(m); 1135 vm_page_wakeup(m); 1136 vm_page_unlock_queues(); 1137 } 1138 pmap_qenter(ks, ma, pages); 1139} 1140 1141/*************************************************** 1142 * Page table page management routines..... 1143 ***************************************************/ 1144 1145/* 1146 * This routine unholds page table pages, and if the hold count 1147 * drops to zero, then it decrements the wire count. 1148 */ 1149static int 1150_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1151{ 1152 1153 while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) 1154 ; 1155 1156 if (m->hold_count == 0) { 1157 vm_offset_t pteva; 1158 /* 1159 * unmap the page table page 1160 */ 1161 pmap->pm_pdir[m->pindex] = 0; 1162 --pmap->pm_stats.resident_count; 1163 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1164 (PTDpde & PG_FRAME)) { 1165 /* 1166 * Do a invltlb to make the invalidated mapping 1167 * take effect immediately. 1168 */ 1169 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); 1170 pmap_invalidate_page(pmap, pteva); 1171 } 1172 1173 if (pmap->pm_ptphint == m) 1174 pmap->pm_ptphint = NULL; 1175 1176 /* 1177 * If the page is finally unwired, simply free it. 1178 */ 1179 --m->wire_count; 1180 if (m->wire_count == 0) { 1181 vm_page_busy(m); 1182 vm_page_free_zero(m); 1183 --cnt.v_wire_count; 1184 } 1185 return 1; 1186 } 1187 return 0; 1188} 1189 1190static PMAP_INLINE int 1191pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1192{ 1193 vm_page_unhold(m); 1194 if (m->hold_count == 0) 1195 return _pmap_unwire_pte_hold(pmap, m); 1196 else 1197 return 0; 1198} 1199 1200/* 1201 * After removing a page table entry, this routine is used to 1202 * conditionally free the page, and manage the hold/wire counts. 1203 */ 1204static int 1205pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1206{ 1207 unsigned ptepindex; 1208 if (va >= VM_MAXUSER_ADDRESS) 1209 return 0; 1210 1211 if (mpte == NULL) { 1212 ptepindex = (va >> PDRSHIFT); 1213 if (pmap->pm_ptphint && 1214 (pmap->pm_ptphint->pindex == ptepindex)) { 1215 mpte = pmap->pm_ptphint; 1216 } else { 1217 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1218 pmap->pm_ptphint = mpte; 1219 } 1220 } 1221 1222 return pmap_unwire_pte_hold(pmap, mpte); 1223} 1224 1225void 1226pmap_pinit0(pmap) 1227 struct pmap *pmap; 1228{ 1229 pmap->pm_pdir = 1230 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1231 pmap_kenter((vm_offset_t)pmap->pm_pdir, (vm_offset_t)IdlePTD); 1232#ifndef I386_CPU 1233 invlpg((vm_offset_t)pmap->pm_pdir); 1234#else 1235 invltlb(); 1236#endif 1237 pmap->pm_ptphint = NULL; 1238 pmap->pm_active = 0; 1239 TAILQ_INIT(&pmap->pm_pvlist); 1240 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1241 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1242} 1243 1244/* 1245 * Initialize a preallocated and zeroed pmap structure, 1246 * such as one in a vmspace structure. 1247 */ 1248void 1249pmap_pinit(pmap) 1250 register struct pmap *pmap; 1251{ 1252 vm_page_t ptdpg; 1253 1254 /* 1255 * No need to allocate page table space yet but we do need a valid 1256 * page directory table. 1257 */ 1258 if (pmap->pm_pdir == NULL) 1259 pmap->pm_pdir = 1260 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1261 1262 /* 1263 * allocate object for the ptes 1264 */ 1265 if (pmap->pm_pteobj == NULL) 1266 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1267 1268 /* 1269 * allocate the page directory page 1270 */ 1271 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1272 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED | VM_ALLOC_ZERO); 1273 vm_page_flag_clear(ptdpg, PG_BUSY); 1274 ptdpg->valid = VM_PAGE_BITS_ALL; 1275 1276 pmap_qenter((vm_offset_t) pmap->pm_pdir, &ptdpg, 1); 1277 if ((ptdpg->flags & PG_ZERO) == 0) 1278 bzero(pmap->pm_pdir, PAGE_SIZE); 1279 1280 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1281 /* Wire in kernel global address entries. */ 1282 /* XXX copies current process, does not fill in MPPTDI */ 1283 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1284#ifdef SMP 1285 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1286#endif 1287 1288 /* install self-referential address mapping entry */ 1289 pmap->pm_pdir[PTDPTDI] = 1290 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1291 1292 pmap->pm_active = 0; 1293 pmap->pm_ptphint = NULL; 1294 TAILQ_INIT(&pmap->pm_pvlist); 1295 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1296} 1297 1298/* 1299 * Wire in kernel global address entries. To avoid a race condition 1300 * between pmap initialization and pmap_growkernel, this procedure 1301 * should be called after the vmspace is attached to the process 1302 * but before this pmap is activated. 1303 */ 1304void 1305pmap_pinit2(pmap) 1306 struct pmap *pmap; 1307{ 1308 /* XXX: Remove this stub when no longer called */ 1309} 1310 1311static int 1312pmap_release_free_page(pmap_t pmap, vm_page_t p) 1313{ 1314 pd_entry_t *pde = pmap->pm_pdir; 1315 1316 /* 1317 * This code optimizes the case of freeing non-busy 1318 * page-table pages. Those pages are zero now, and 1319 * might as well be placed directly into the zero queue. 1320 */ 1321 vm_page_lock_queues(); 1322 if (vm_page_sleep_if_busy(p, FALSE, "pmaprl")) 1323 return (0); 1324 vm_page_busy(p); 1325 1326 /* 1327 * Remove the page table page from the processes address space. 1328 */ 1329 pde[p->pindex] = 0; 1330 pmap->pm_stats.resident_count--; 1331 1332 if (p->hold_count) { 1333 panic("pmap_release: freeing held page table page"); 1334 } 1335 /* 1336 * Page directory pages need to have the kernel 1337 * stuff cleared, so they can go into the zero queue also. 1338 */ 1339 if (p->pindex == PTDPTDI) { 1340 bzero(pde + KPTDI, nkpt * PTESIZE); 1341#ifdef SMP 1342 pde[MPPTDI] = 0; 1343#endif 1344 pde[APTDPTDI] = 0; 1345 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1346 } 1347 1348 if (pmap->pm_ptphint == p) 1349 pmap->pm_ptphint = NULL; 1350 1351 p->wire_count--; 1352 cnt.v_wire_count--; 1353 vm_page_free_zero(p); 1354 vm_page_unlock_queues(); 1355 return 1; 1356} 1357 1358/* 1359 * this routine is called if the page table page is not 1360 * mapped correctly. 1361 */ 1362static vm_page_t 1363_pmap_allocpte(pmap, ptepindex) 1364 pmap_t pmap; 1365 unsigned ptepindex; 1366{ 1367 vm_offset_t pteva, ptepa; /* XXXPA */ 1368 vm_page_t m; 1369 1370 /* 1371 * Find or fabricate a new pagetable page 1372 */ 1373 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1374 VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1375 1376 KASSERT(m->queue == PQ_NONE, 1377 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1378 1379 /* 1380 * Increment the hold count for the page table page 1381 * (denoting a new mapping.) 1382 */ 1383 m->hold_count++; 1384 1385 /* 1386 * Map the pagetable page into the process address space, if 1387 * it isn't already there. 1388 */ 1389 1390 pmap->pm_stats.resident_count++; 1391 1392 ptepa = VM_PAGE_TO_PHYS(m); 1393 pmap->pm_pdir[ptepindex] = 1394 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1395 1396 /* 1397 * Set the page table hint 1398 */ 1399 pmap->pm_ptphint = m; 1400 1401 /* 1402 * Try to use the new mapping, but if we cannot, then 1403 * do it with the routine that maps the page explicitly. 1404 */ 1405 if ((m->flags & PG_ZERO) == 0) { 1406 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1407 (PTDpde & PG_FRAME)) { 1408 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1409 bzero((caddr_t) pteva, PAGE_SIZE); 1410 } else { 1411 pmap_zero_page(m); 1412 } 1413 } 1414 1415 m->valid = VM_PAGE_BITS_ALL; 1416 vm_page_flag_clear(m, PG_ZERO); 1417 vm_page_wakeup(m); 1418 1419 return m; 1420} 1421 1422static vm_page_t 1423pmap_allocpte(pmap_t pmap, vm_offset_t va) 1424{ 1425 unsigned ptepindex; 1426 pd_entry_t ptepa; 1427 vm_page_t m; 1428 1429 /* 1430 * Calculate pagetable page index 1431 */ 1432 ptepindex = va >> PDRSHIFT; 1433 1434 /* 1435 * Get the page directory entry 1436 */ 1437 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1438 1439 /* 1440 * This supports switching from a 4MB page to a 1441 * normal 4K page. 1442 */ 1443 if (ptepa & PG_PS) { 1444 pmap->pm_pdir[ptepindex] = 0; 1445 ptepa = 0; 1446 pmap_invalidate_all(kernel_pmap); 1447 } 1448 1449 /* 1450 * If the page table page is mapped, we just increment the 1451 * hold count, and activate it. 1452 */ 1453 if (ptepa) { 1454 /* 1455 * In order to get the page table page, try the 1456 * hint first. 1457 */ 1458 if (pmap->pm_ptphint && 1459 (pmap->pm_ptphint->pindex == ptepindex)) { 1460 m = pmap->pm_ptphint; 1461 } else { 1462 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1463 pmap->pm_ptphint = m; 1464 } 1465 m->hold_count++; 1466 return m; 1467 } 1468 /* 1469 * Here if the pte page isn't mapped, or if it has been deallocated. 1470 */ 1471 return _pmap_allocpte(pmap, ptepindex); 1472} 1473 1474 1475/*************************************************** 1476* Pmap allocation/deallocation routines. 1477 ***************************************************/ 1478 1479/* 1480 * Release any resources held by the given physical map. 1481 * Called when a pmap initialized by pmap_pinit is being released. 1482 * Should only be called if the map contains no valid mappings. 1483 */ 1484void 1485pmap_release(pmap_t pmap) 1486{ 1487 vm_page_t p,n,ptdpg; 1488 vm_object_t object = pmap->pm_pteobj; 1489 int curgeneration; 1490 1491#if defined(DIAGNOSTIC) 1492 if (object->ref_count != 1) 1493 panic("pmap_release: pteobj reference count != 1"); 1494#endif 1495 1496 ptdpg = NULL; 1497 LIST_REMOVE(pmap, pm_list); 1498retry: 1499 curgeneration = object->generation; 1500 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1501 n = TAILQ_NEXT(p, listq); 1502 if (p->pindex == PTDPTDI) { 1503 ptdpg = p; 1504 continue; 1505 } 1506 while (1) { 1507 if (!pmap_release_free_page(pmap, p) && 1508 (object->generation != curgeneration)) 1509 goto retry; 1510 } 1511 } 1512 1513 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1514 goto retry; 1515} 1516 1517static int 1518kvm_size(SYSCTL_HANDLER_ARGS) 1519{ 1520 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1521 1522 return sysctl_handle_long(oidp, &ksize, 0, req); 1523} 1524SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1525 0, 0, kvm_size, "IU", "Size of KVM"); 1526 1527static int 1528kvm_free(SYSCTL_HANDLER_ARGS) 1529{ 1530 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1531 1532 return sysctl_handle_long(oidp, &kfree, 0, req); 1533} 1534SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1535 0, 0, kvm_free, "IU", "Amount of KVM free"); 1536 1537/* 1538 * grow the number of kernel page table entries, if needed 1539 */ 1540void 1541pmap_growkernel(vm_offset_t addr) 1542{ 1543 struct pmap *pmap; 1544 int s; 1545 vm_offset_t ptppaddr; 1546 vm_page_t nkpg; 1547 pd_entry_t newpdir; 1548 1549 s = splhigh(); 1550 if (kernel_vm_end == 0) { 1551 kernel_vm_end = KERNBASE; 1552 nkpt = 0; 1553 while (pdir_pde(PTD, kernel_vm_end)) { 1554 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1555 nkpt++; 1556 } 1557 } 1558 addr = roundup2(addr, PAGE_SIZE * NPTEPG); 1559 while (kernel_vm_end < addr) { 1560 if (pdir_pde(PTD, kernel_vm_end)) { 1561 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1562 continue; 1563 } 1564 1565 /* 1566 * This index is bogus, but out of the way 1567 */ 1568 nkpg = vm_page_alloc(kptobj, nkpt, 1569 VM_ALLOC_SYSTEM | VM_ALLOC_WIRED); 1570 if (!nkpg) 1571 panic("pmap_growkernel: no memory to grow kernel"); 1572 1573 nkpt++; 1574 1575 pmap_zero_page(nkpg); 1576 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1577 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1578 pdir_pde(PTD, kernel_vm_end) = newpdir; 1579 1580 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1581 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1582 } 1583 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1584 } 1585 splx(s); 1586} 1587 1588 1589/*************************************************** 1590 * page management routines. 1591 ***************************************************/ 1592 1593/* 1594 * free the pv_entry back to the free list 1595 */ 1596static PMAP_INLINE void 1597free_pv_entry(pv_entry_t pv) 1598{ 1599 pv_entry_count--; 1600 uma_zfree(pvzone, pv); 1601} 1602 1603/* 1604 * get a new pv_entry, allocating a block from the system 1605 * when needed. 1606 * the memory allocation is performed bypassing the malloc code 1607 * because of the possibility of allocations at interrupt time. 1608 */ 1609static pv_entry_t 1610get_pv_entry(void) 1611{ 1612 pv_entry_count++; 1613 if (pv_entry_high_water && 1614 (pv_entry_count > pv_entry_high_water) && 1615 (pmap_pagedaemon_waken == 0)) { 1616 pmap_pagedaemon_waken = 1; 1617 wakeup (&vm_pages_needed); 1618 } 1619 return uma_zalloc(pvzone, M_NOWAIT); 1620} 1621 1622/* 1623 * This routine is very drastic, but can save the system 1624 * in a pinch. 1625 */ 1626void 1627pmap_collect() 1628{ 1629 int i; 1630 vm_page_t m; 1631 static int warningdone = 0; 1632 1633 if (pmap_pagedaemon_waken == 0) 1634 return; 1635 1636 if (warningdone < 5) { 1637 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1638 warningdone++; 1639 } 1640 1641 for(i = 0; i < vm_page_array_size; i++) { 1642 m = &vm_page_array[i]; 1643 if (m->wire_count || m->hold_count || m->busy || 1644 (m->flags & (PG_BUSY | PG_UNMANAGED))) 1645 continue; 1646 pmap_remove_all(m); 1647 } 1648 pmap_pagedaemon_waken = 0; 1649} 1650 1651 1652/* 1653 * If it is the first entry on the list, it is actually 1654 * in the header and we must copy the following entry up 1655 * to the header. Otherwise we must search the list for 1656 * the entry. In either case we free the now unused entry. 1657 */ 1658 1659static int 1660pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1661{ 1662 pv_entry_t pv; 1663 int rtval; 1664 int s; 1665 1666 s = splvm(); 1667 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1668 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1669 if (pmap == pv->pv_pmap && va == pv->pv_va) 1670 break; 1671 } 1672 } else { 1673 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1674 if (va == pv->pv_va) 1675 break; 1676 } 1677 } 1678 1679 rtval = 0; 1680 if (pv) { 1681 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1682 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1683 m->md.pv_list_count--; 1684 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1685 vm_page_flag_clear(m, PG_WRITEABLE); 1686 1687 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1688 free_pv_entry(pv); 1689 } 1690 1691 splx(s); 1692 return rtval; 1693} 1694 1695/* 1696 * Create a pv entry for page at pa for 1697 * (pmap, va). 1698 */ 1699static void 1700pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1701{ 1702 1703 int s; 1704 pv_entry_t pv; 1705 1706 s = splvm(); 1707 pv = get_pv_entry(); 1708 pv->pv_va = va; 1709 pv->pv_pmap = pmap; 1710 pv->pv_ptem = mpte; 1711 1712 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1713 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1714 m->md.pv_list_count++; 1715 1716 splx(s); 1717} 1718 1719/* 1720 * pmap_remove_pte: do the things to unmap a page in a process 1721 */ 1722static int 1723pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1724{ 1725 pt_entry_t oldpte; 1726 vm_page_t m; 1727 1728 oldpte = atomic_readandclear_int(ptq); 1729 if (oldpte & PG_W) 1730 pmap->pm_stats.wired_count -= 1; 1731 /* 1732 * Machines that don't support invlpg, also don't support 1733 * PG_G. 1734 */ 1735 if (oldpte & PG_G) 1736 pmap_invalidate_page(kernel_pmap, va); 1737 pmap->pm_stats.resident_count -= 1; 1738 if (oldpte & PG_MANAGED) { 1739 m = PHYS_TO_VM_PAGE(oldpte); 1740 if (oldpte & PG_M) { 1741#if defined(PMAP_DIAGNOSTIC) 1742 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1743 printf( 1744 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1745 va, oldpte); 1746 } 1747#endif 1748 if (pmap_track_modified(va)) 1749 vm_page_dirty(m); 1750 } 1751 if (oldpte & PG_A) 1752 vm_page_flag_set(m, PG_REFERENCED); 1753 return pmap_remove_entry(pmap, m, va); 1754 } else { 1755 return pmap_unuse_pt(pmap, va, NULL); 1756 } 1757 1758 return 0; 1759} 1760 1761/* 1762 * Remove a single page from a process address space 1763 */ 1764static void 1765pmap_remove_page(pmap_t pmap, vm_offset_t va) 1766{ 1767 register pt_entry_t *ptq; 1768 1769 /* 1770 * if there is no pte for this address, just skip it!!! 1771 */ 1772 if (*pmap_pde(pmap, va) == 0) { 1773 return; 1774 } 1775 1776 /* 1777 * get a local va for mappings for this pmap. 1778 */ 1779 ptq = get_ptbase(pmap) + i386_btop(va); 1780 if (*ptq) { 1781 (void) pmap_remove_pte(pmap, ptq, va); 1782 pmap_invalidate_page(pmap, va); 1783 } 1784 return; 1785} 1786 1787/* 1788 * Remove the given range of addresses from the specified map. 1789 * 1790 * It is assumed that the start and end are properly 1791 * rounded to the page size. 1792 */ 1793void 1794pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1795{ 1796 register pt_entry_t *ptbase; 1797 vm_offset_t pdnxt; 1798 pd_entry_t ptpaddr; 1799 vm_offset_t sindex, eindex; 1800 int anyvalid; 1801 1802 if (pmap == NULL) 1803 return; 1804 1805 if (pmap->pm_stats.resident_count == 0) 1806 return; 1807 1808 /* 1809 * special handling of removing one page. a very 1810 * common operation and easy to short circuit some 1811 * code. 1812 */ 1813 if ((sva + PAGE_SIZE == eva) && 1814 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1815 pmap_remove_page(pmap, sva); 1816 return; 1817 } 1818 1819 anyvalid = 0; 1820 1821 /* 1822 * Get a local virtual address for the mappings that are being 1823 * worked with. 1824 */ 1825 ptbase = get_ptbase(pmap); 1826 1827 sindex = i386_btop(sva); 1828 eindex = i386_btop(eva); 1829 1830 for (; sindex < eindex; sindex = pdnxt) { 1831 unsigned pdirindex; 1832 1833 /* 1834 * Calculate index for next page table. 1835 */ 1836 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1837 if (pmap->pm_stats.resident_count == 0) 1838 break; 1839 1840 pdirindex = sindex / NPDEPG; 1841 ptpaddr = pmap->pm_pdir[pdirindex]; 1842 if ((ptpaddr & PG_PS) != 0) { 1843 pmap->pm_pdir[pdirindex] = 0; 1844 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1845 anyvalid++; 1846 continue; 1847 } 1848 1849 /* 1850 * Weed out invalid mappings. Note: we assume that the page 1851 * directory table is always allocated, and in kernel virtual. 1852 */ 1853 if (ptpaddr == 0) 1854 continue; 1855 1856 /* 1857 * Limit our scan to either the end of the va represented 1858 * by the current page table page, or to the end of the 1859 * range being removed. 1860 */ 1861 if (pdnxt > eindex) { 1862 pdnxt = eindex; 1863 } 1864 1865 for (; sindex != pdnxt; sindex++) { 1866 vm_offset_t va; 1867 if (ptbase[sindex] == 0) { 1868 continue; 1869 } 1870 va = i386_ptob(sindex); 1871 1872 anyvalid++; 1873 if (pmap_remove_pte(pmap, 1874 ptbase + sindex, va)) 1875 break; 1876 } 1877 } 1878 1879 if (anyvalid) 1880 pmap_invalidate_all(pmap); 1881} 1882 1883/* 1884 * Routine: pmap_remove_all 1885 * Function: 1886 * Removes this physical page from 1887 * all physical maps in which it resides. 1888 * Reflects back modify bits to the pager. 1889 * 1890 * Notes: 1891 * Original versions of this routine were very 1892 * inefficient because they iteratively called 1893 * pmap_remove (slow...) 1894 */ 1895 1896static void 1897pmap_remove_all(vm_page_t m) 1898{ 1899 register pv_entry_t pv; 1900 pt_entry_t *pte, tpte; 1901 int s; 1902 1903#if defined(PMAP_DIAGNOSTIC) 1904 /* 1905 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1906 * pages! 1907 */ 1908 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1909 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1910 } 1911#endif 1912 1913 s = splvm(); 1914 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1915 pv->pv_pmap->pm_stats.resident_count--; 1916 1917 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1918 1919 tpte = atomic_readandclear_int(pte); 1920 if (tpte & PG_W) 1921 pv->pv_pmap->pm_stats.wired_count--; 1922 1923 if (tpte & PG_A) 1924 vm_page_flag_set(m, PG_REFERENCED); 1925 1926 /* 1927 * Update the vm_page_t clean and reference bits. 1928 */ 1929 if (tpte & PG_M) { 1930#if defined(PMAP_DIAGNOSTIC) 1931 if (pmap_nw_modified((pt_entry_t) tpte)) { 1932 printf( 1933 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1934 pv->pv_va, tpte); 1935 } 1936#endif 1937 if (pmap_track_modified(pv->pv_va)) 1938 vm_page_dirty(m); 1939 } 1940 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1941 1942 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1943 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1944 m->md.pv_list_count--; 1945 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1946 free_pv_entry(pv); 1947 } 1948 1949 vm_page_flag_clear(m, PG_WRITEABLE); 1950 1951 splx(s); 1952} 1953 1954/* 1955 * Set the physical protection on the 1956 * specified range of this map as requested. 1957 */ 1958void 1959pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1960{ 1961 register pt_entry_t *ptbase; 1962 vm_offset_t pdnxt; 1963 pd_entry_t ptpaddr; 1964 vm_offset_t sindex, eindex; 1965 int anychanged; 1966 1967 if (pmap == NULL) 1968 return; 1969 1970 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1971 pmap_remove(pmap, sva, eva); 1972 return; 1973 } 1974 1975 if (prot & VM_PROT_WRITE) 1976 return; 1977 1978 anychanged = 0; 1979 1980 ptbase = get_ptbase(pmap); 1981 1982 sindex = i386_btop(sva); 1983 eindex = i386_btop(eva); 1984 1985 for (; sindex < eindex; sindex = pdnxt) { 1986 1987 unsigned pdirindex; 1988 1989 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1990 1991 pdirindex = sindex / NPDEPG; 1992 ptpaddr = pmap->pm_pdir[pdirindex]; 1993 if ((ptpaddr & PG_PS) != 0) { 1994 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1995 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1996 anychanged++; 1997 continue; 1998 } 1999 2000 /* 2001 * Weed out invalid mappings. Note: we assume that the page 2002 * directory table is always allocated, and in kernel virtual. 2003 */ 2004 if (ptpaddr == 0) 2005 continue; 2006 2007 if (pdnxt > eindex) { 2008 pdnxt = eindex; 2009 } 2010 2011 for (; sindex != pdnxt; sindex++) { 2012 2013 pt_entry_t pbits; 2014 vm_page_t m; 2015 2016 pbits = ptbase[sindex]; 2017 2018 if (pbits & PG_MANAGED) { 2019 m = NULL; 2020 if (pbits & PG_A) { 2021 m = PHYS_TO_VM_PAGE(pbits); 2022 vm_page_flag_set(m, PG_REFERENCED); 2023 pbits &= ~PG_A; 2024 } 2025 if (pbits & PG_M) { 2026 if (pmap_track_modified(i386_ptob(sindex))) { 2027 if (m == NULL) 2028 m = PHYS_TO_VM_PAGE(pbits); 2029 vm_page_dirty(m); 2030 pbits &= ~PG_M; 2031 } 2032 } 2033 } 2034 2035 pbits &= ~PG_RW; 2036 2037 if (pbits != ptbase[sindex]) { 2038 ptbase[sindex] = pbits; 2039 anychanged = 1; 2040 } 2041 } 2042 } 2043 if (anychanged) 2044 pmap_invalidate_all(pmap); 2045} 2046 2047/* 2048 * Insert the given physical page (p) at 2049 * the specified virtual address (v) in the 2050 * target physical map with the protection requested. 2051 * 2052 * If specified, the page will be wired down, meaning 2053 * that the related pte can not be reclaimed. 2054 * 2055 * NB: This is the only routine which MAY NOT lazy-evaluate 2056 * or lose information. That is, this routine must actually 2057 * insert this page into the given map NOW. 2058 */ 2059void 2060pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2061 boolean_t wired) 2062{ 2063 vm_offset_t pa; 2064 register pt_entry_t *pte; 2065 vm_offset_t opa; 2066 pt_entry_t origpte, newpte; 2067 vm_page_t mpte; 2068 2069 if (pmap == NULL) 2070 return; 2071 2072 va &= PG_FRAME; 2073#ifdef PMAP_DIAGNOSTIC 2074 if (va > VM_MAX_KERNEL_ADDRESS) 2075 panic("pmap_enter: toobig"); 2076 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2077 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2078#endif 2079 2080 mpte = NULL; 2081 /* 2082 * In the case that a page table page is not 2083 * resident, we are creating it here. 2084 */ 2085 if (va < VM_MAXUSER_ADDRESS) { 2086 mpte = pmap_allocpte(pmap, va); 2087 } 2088#if 0 && defined(PMAP_DIAGNOSTIC) 2089 else { 2090 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2091 origpte = *pdeaddr; 2092 if ((origpte & PG_V) == 0) { 2093 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2094 pmap->pm_pdir[PTDPTDI], origpte, va); 2095 } 2096 } 2097#endif 2098 2099 pte = pmap_pte(pmap, va); 2100 2101 /* 2102 * Page Directory table entry not valid, we need a new PT page 2103 */ 2104 if (pte == NULL) { 2105 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2106 (void *)pmap->pm_pdir[PTDPTDI], va); 2107 } 2108 2109 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2110 origpte = *(vm_offset_t *)pte; 2111 opa = origpte & PG_FRAME; 2112 2113 if (origpte & PG_PS) 2114 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2115 2116 /* 2117 * Mapping has not changed, must be protection or wiring change. 2118 */ 2119 if (origpte && (opa == pa)) { 2120 /* 2121 * Wiring change, just update stats. We don't worry about 2122 * wiring PT pages as they remain resident as long as there 2123 * are valid mappings in them. Hence, if a user page is wired, 2124 * the PT page will be also. 2125 */ 2126 if (wired && ((origpte & PG_W) == 0)) 2127 pmap->pm_stats.wired_count++; 2128 else if (!wired && (origpte & PG_W)) 2129 pmap->pm_stats.wired_count--; 2130 2131#if defined(PMAP_DIAGNOSTIC) 2132 if (pmap_nw_modified((pt_entry_t) origpte)) { 2133 printf( 2134 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2135 va, origpte); 2136 } 2137#endif 2138 2139 /* 2140 * Remove extra pte reference 2141 */ 2142 if (mpte) 2143 mpte->hold_count--; 2144 2145 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2146 if ((origpte & PG_RW) == 0) { 2147 *pte |= PG_RW; 2148 pmap_invalidate_page(pmap, va); 2149 } 2150 return; 2151 } 2152 2153 /* 2154 * We might be turning off write access to the page, 2155 * so we go ahead and sense modify status. 2156 */ 2157 if (origpte & PG_MANAGED) { 2158 if ((origpte & PG_M) && pmap_track_modified(va)) { 2159 vm_page_t om; 2160 om = PHYS_TO_VM_PAGE(opa); 2161 vm_page_dirty(om); 2162 } 2163 pa |= PG_MANAGED; 2164 } 2165 goto validate; 2166 } 2167 /* 2168 * Mapping has changed, invalidate old range and fall through to 2169 * handle validating new mapping. 2170 */ 2171 if (opa) { 2172 int err; 2173 err = pmap_remove_pte(pmap, pte, va); 2174 if (err) 2175 panic("pmap_enter: pte vanished, va: 0x%x", va); 2176 } 2177 2178 /* 2179 * Enter on the PV list if part of our managed memory. Note that we 2180 * raise IPL while manipulating pv_table since pmap_enter can be 2181 * called at interrupt time. 2182 */ 2183 if (pmap_initialized && 2184 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2185 pmap_insert_entry(pmap, va, mpte, m); 2186 pa |= PG_MANAGED; 2187 } 2188 2189 /* 2190 * Increment counters 2191 */ 2192 pmap->pm_stats.resident_count++; 2193 if (wired) 2194 pmap->pm_stats.wired_count++; 2195 2196validate: 2197 /* 2198 * Now validate mapping with desired protection/wiring. 2199 */ 2200 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2201 2202 if (wired) 2203 newpte |= PG_W; 2204 if (va < VM_MAXUSER_ADDRESS) 2205 newpte |= PG_U; 2206 if (pmap == kernel_pmap) 2207 newpte |= pgeflag; 2208 2209 /* 2210 * if the mapping or permission bits are different, we need 2211 * to update the pte. 2212 */ 2213 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2214 *pte = newpte | PG_A; 2215 /*if (origpte)*/ { 2216 pmap_invalidate_page(pmap, va); 2217 } 2218 } 2219} 2220 2221/* 2222 * this code makes some *MAJOR* assumptions: 2223 * 1. Current pmap & pmap exists. 2224 * 2. Not wired. 2225 * 3. Read access. 2226 * 4. No page table pages. 2227 * 5. Tlbflush is deferred to calling procedure. 2228 * 6. Page IS managed. 2229 * but is *MUCH* faster than pmap_enter... 2230 */ 2231 2232static vm_page_t 2233pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2234{ 2235 pt_entry_t *pte; 2236 vm_offset_t pa; 2237 2238 /* 2239 * In the case that a page table page is not 2240 * resident, we are creating it here. 2241 */ 2242 if (va < VM_MAXUSER_ADDRESS) { 2243 unsigned ptepindex; 2244 pd_entry_t ptepa; 2245 2246 /* 2247 * Calculate pagetable page index 2248 */ 2249 ptepindex = va >> PDRSHIFT; 2250 if (mpte && (mpte->pindex == ptepindex)) { 2251 mpte->hold_count++; 2252 } else { 2253retry: 2254 /* 2255 * Get the page directory entry 2256 */ 2257 ptepa = pmap->pm_pdir[ptepindex]; 2258 2259 /* 2260 * If the page table page is mapped, we just increment 2261 * the hold count, and activate it. 2262 */ 2263 if (ptepa) { 2264 if (ptepa & PG_PS) 2265 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2266 if (pmap->pm_ptphint && 2267 (pmap->pm_ptphint->pindex == ptepindex)) { 2268 mpte = pmap->pm_ptphint; 2269 } else { 2270 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2271 pmap->pm_ptphint = mpte; 2272 } 2273 if (mpte == NULL) 2274 goto retry; 2275 mpte->hold_count++; 2276 } else { 2277 mpte = _pmap_allocpte(pmap, ptepindex); 2278 } 2279 } 2280 } else { 2281 mpte = NULL; 2282 } 2283 2284 /* 2285 * This call to vtopte makes the assumption that we are 2286 * entering the page into the current pmap. In order to support 2287 * quick entry into any pmap, one would likely use pmap_pte_quick. 2288 * But that isn't as quick as vtopte. 2289 */ 2290 pte = vtopte(va); 2291 if (*pte) { 2292 if (mpte) 2293 pmap_unwire_pte_hold(pmap, mpte); 2294 return 0; 2295 } 2296 2297 /* 2298 * Enter on the PV list if part of our managed memory. Note that we 2299 * raise IPL while manipulating pv_table since pmap_enter can be 2300 * called at interrupt time. 2301 */ 2302 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2303 pmap_insert_entry(pmap, va, mpte, m); 2304 2305 /* 2306 * Increment counters 2307 */ 2308 pmap->pm_stats.resident_count++; 2309 2310 pa = VM_PAGE_TO_PHYS(m); 2311 2312 /* 2313 * Now validate mapping with RO protection 2314 */ 2315 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2316 *pte = pa | PG_V | PG_U; 2317 else 2318 *pte = pa | PG_V | PG_U | PG_MANAGED; 2319 2320 return mpte; 2321} 2322 2323/* 2324 * Make a temporary mapping for a physical address. This is only intended 2325 * to be used for panic dumps. 2326 */ 2327void * 2328pmap_kenter_temporary(vm_offset_t pa, int i) 2329{ 2330 vm_offset_t va; 2331 2332 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE); 2333 pmap_kenter(va, pa); 2334#ifndef I386_CPU 2335 invlpg(va); 2336#else 2337 invltlb(); 2338#endif 2339 return ((void *)crashdumpmap); 2340} 2341 2342#define MAX_INIT_PT (96) 2343/* 2344 * pmap_object_init_pt preloads the ptes for a given object 2345 * into the specified pmap. This eliminates the blast of soft 2346 * faults on process startup and immediately after an mmap. 2347 */ 2348void 2349pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2350 vm_object_t object, vm_pindex_t pindex, 2351 vm_size_t size, int limit) 2352{ 2353 vm_offset_t tmpidx; 2354 int psize; 2355 vm_page_t p, mpte; 2356 2357 if (pmap == NULL || object == NULL) 2358 return; 2359 2360 /* 2361 * This code maps large physical mmap regions into the 2362 * processor address space. Note that some shortcuts 2363 * are taken, but the code works. 2364 */ 2365 if (pseflag && (object->type == OBJT_DEVICE) && 2366 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2367 int i; 2368 vm_page_t m[1]; 2369 unsigned int ptepindex; 2370 int npdes; 2371 pd_entry_t ptepa; 2372 2373 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2374 return; 2375 2376retry: 2377 p = vm_page_lookup(object, pindex); 2378 if (p != NULL) { 2379 vm_page_lock_queues(); 2380 if (vm_page_sleep_if_busy(p, FALSE, "init4p")) 2381 goto retry; 2382 vm_page_unlock_queues(); 2383 } else { 2384 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2385 if (p == NULL) 2386 return; 2387 m[0] = p; 2388 2389 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2390 vm_page_lock_queues(); 2391 vm_page_free(p); 2392 vm_page_unlock_queues(); 2393 return; 2394 } 2395 2396 p = vm_page_lookup(object, pindex); 2397 vm_page_wakeup(p); 2398 } 2399 2400 ptepa = VM_PAGE_TO_PHYS(p); 2401 if (ptepa & (NBPDR - 1)) { 2402 return; 2403 } 2404 2405 p->valid = VM_PAGE_BITS_ALL; 2406 2407 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2408 npdes = size >> PDRSHIFT; 2409 for(i = 0; i < npdes; i++) { 2410 pmap->pm_pdir[ptepindex] = 2411 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2412 ptepa += NBPDR; 2413 ptepindex += 1; 2414 } 2415 pmap_invalidate_all(kernel_pmap); 2416 return; 2417 } 2418 2419 psize = i386_btop(size); 2420 2421 if ((object->type != OBJT_VNODE) || 2422 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2423 (object->resident_page_count > MAX_INIT_PT))) { 2424 return; 2425 } 2426 2427 if (psize + pindex > object->size) { 2428 if (object->size < pindex) 2429 return; 2430 psize = object->size - pindex; 2431 } 2432 2433 mpte = NULL; 2434 2435 if ((p = TAILQ_FIRST(&object->memq)) != NULL) { 2436 if (p->pindex < pindex) { 2437 p = vm_page_splay(pindex, object->root); 2438 if ((object->root = p)->pindex < pindex) 2439 p = TAILQ_NEXT(p, listq); 2440 } 2441 } 2442 /* 2443 * Assert: the variable p is either (1) the page with the 2444 * least pindex greater than or equal to the parameter pindex 2445 * or (2) NULL. 2446 */ 2447 for (; 2448 p != NULL && (tmpidx = p->pindex - pindex) < psize; 2449 p = TAILQ_NEXT(p, listq)) { 2450 /* 2451 * don't allow an madvise to blow away our really 2452 * free pages allocating pv entries. 2453 */ 2454 if ((limit & MAP_PREFAULT_MADVISE) && 2455 cnt.v_free_count < cnt.v_free_reserved) { 2456 break; 2457 } 2458 vm_page_lock_queues(); 2459 if ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL && 2460 (p->busy == 0) && 2461 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2462 if ((p->queue - p->pc) == PQ_CACHE) 2463 vm_page_deactivate(p); 2464 vm_page_busy(p); 2465 vm_page_unlock_queues(); 2466 mpte = pmap_enter_quick(pmap, 2467 addr + i386_ptob(tmpidx), p, mpte); 2468 vm_page_lock_queues(); 2469 vm_page_wakeup(p); 2470 } 2471 vm_page_unlock_queues(); 2472 } 2473 return; 2474} 2475 2476/* 2477 * pmap_prefault provides a quick way of clustering 2478 * pagefaults into a processes address space. It is a "cousin" 2479 * of pmap_object_init_pt, except it runs at page fault time instead 2480 * of mmap time. 2481 */ 2482#define PFBAK 4 2483#define PFFOR 4 2484#define PAGEORDER_SIZE (PFBAK+PFFOR) 2485 2486static int pmap_prefault_pageorder[] = { 2487 -1 * PAGE_SIZE, 1 * PAGE_SIZE, 2488 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2489 -3 * PAGE_SIZE, 3 * PAGE_SIZE, 2490 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2491}; 2492 2493void 2494pmap_prefault(pmap, addra, entry) 2495 pmap_t pmap; 2496 vm_offset_t addra; 2497 vm_map_entry_t entry; 2498{ 2499 int i; 2500 vm_offset_t starta; 2501 vm_offset_t addr; 2502 vm_pindex_t pindex; 2503 vm_page_t m, mpte; 2504 vm_object_t object; 2505 2506 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2507 return; 2508 2509 object = entry->object.vm_object; 2510 2511 starta = addra - PFBAK * PAGE_SIZE; 2512 if (starta < entry->start) { 2513 starta = entry->start; 2514 } else if (starta > addra) { 2515 starta = 0; 2516 } 2517 2518 mpte = NULL; 2519 for (i = 0; i < PAGEORDER_SIZE; i++) { 2520 vm_object_t lobject; 2521 pt_entry_t *pte; 2522 2523 addr = addra + pmap_prefault_pageorder[i]; 2524 if (addr > addra + (PFFOR * PAGE_SIZE)) 2525 addr = 0; 2526 2527 if (addr < starta || addr >= entry->end) 2528 continue; 2529 2530 if ((*pmap_pde(pmap, addr)) == 0) 2531 continue; 2532 2533 pte = vtopte(addr); 2534 if (*pte) 2535 continue; 2536 2537 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2538 lobject = object; 2539 for (m = vm_page_lookup(lobject, pindex); 2540 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2541 lobject = lobject->backing_object) { 2542 if (lobject->backing_object_offset & PAGE_MASK) 2543 break; 2544 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2545 m = vm_page_lookup(lobject->backing_object, pindex); 2546 } 2547 2548 /* 2549 * give-up when a page is not in memory 2550 */ 2551 if (m == NULL) 2552 break; 2553 vm_page_lock_queues(); 2554 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2555 (m->busy == 0) && 2556 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2557 2558 if ((m->queue - m->pc) == PQ_CACHE) { 2559 vm_page_deactivate(m); 2560 } 2561 vm_page_busy(m); 2562 vm_page_unlock_queues(); 2563 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2564 vm_page_lock_queues(); 2565 vm_page_wakeup(m); 2566 } 2567 vm_page_unlock_queues(); 2568 } 2569} 2570 2571/* 2572 * Routine: pmap_change_wiring 2573 * Function: Change the wiring attribute for a map/virtual-address 2574 * pair. 2575 * In/out conditions: 2576 * The mapping must already exist in the pmap. 2577 */ 2578void 2579pmap_change_wiring(pmap, va, wired) 2580 register pmap_t pmap; 2581 vm_offset_t va; 2582 boolean_t wired; 2583{ 2584 register pt_entry_t *pte; 2585 2586 if (pmap == NULL) 2587 return; 2588 2589 pte = pmap_pte(pmap, va); 2590 2591 if (wired && !pmap_pte_w(pte)) 2592 pmap->pm_stats.wired_count++; 2593 else if (!wired && pmap_pte_w(pte)) 2594 pmap->pm_stats.wired_count--; 2595 2596 /* 2597 * Wiring is not a hardware characteristic so there is no need to 2598 * invalidate TLB. 2599 */ 2600 pmap_pte_set_w(pte, wired); 2601} 2602 2603 2604 2605/* 2606 * Copy the range specified by src_addr/len 2607 * from the source map to the range dst_addr/len 2608 * in the destination map. 2609 * 2610 * This routine is only advisory and need not do anything. 2611 */ 2612 2613void 2614pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2615 vm_offset_t src_addr) 2616{ 2617 vm_offset_t addr; 2618 vm_offset_t end_addr = src_addr + len; 2619 vm_offset_t pdnxt; 2620 pd_entry_t src_frame, dst_frame; 2621 vm_page_t m; 2622 2623 if (dst_addr != src_addr) 2624 return; 2625 2626 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2627 if (src_frame != (PTDpde & PG_FRAME)) 2628 return; 2629 2630 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2631 for (addr = src_addr; addr < end_addr; addr = pdnxt) { 2632 pt_entry_t *src_pte, *dst_pte; 2633 vm_page_t dstmpte, srcmpte; 2634 pd_entry_t srcptepaddr; 2635 unsigned ptepindex; 2636 2637 if (addr >= UPT_MIN_ADDRESS) 2638 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2639 2640 /* 2641 * Don't let optional prefaulting of pages make us go 2642 * way below the low water mark of free pages or way 2643 * above high water mark of used pv entries. 2644 */ 2645 if (cnt.v_free_count < cnt.v_free_reserved || 2646 pv_entry_count > pv_entry_high_water) 2647 break; 2648 2649 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2650 ptepindex = addr >> PDRSHIFT; 2651 2652 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2653 if (srcptepaddr == 0) 2654 continue; 2655 2656 if (srcptepaddr & PG_PS) { 2657 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2658 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2659 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2660 } 2661 continue; 2662 } 2663 2664 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2665 if ((srcmpte == NULL) || 2666 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2667 continue; 2668 2669 if (pdnxt > end_addr) 2670 pdnxt = end_addr; 2671 2672 /* 2673 * Have to recheck this before every avtopte() call below 2674 * in case we have blocked and something else used APTDpde. 2675 */ 2676 if (dst_frame != (APTDpde & PG_FRAME)) { 2677 APTDpde = dst_frame | PG_RW | PG_V; 2678 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 2679 } 2680 src_pte = vtopte(addr); 2681 dst_pte = avtopte(addr); 2682 while (addr < pdnxt) { 2683 pt_entry_t ptetemp; 2684 ptetemp = *src_pte; 2685 /* 2686 * we only virtual copy managed pages 2687 */ 2688 if ((ptetemp & PG_MANAGED) != 0) { 2689 /* 2690 * We have to check after allocpte for the 2691 * pte still being around... allocpte can 2692 * block. 2693 */ 2694 dstmpte = pmap_allocpte(dst_pmap, addr); 2695 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2696 /* 2697 * Clear the modified and 2698 * accessed (referenced) bits 2699 * during the copy. 2700 */ 2701 m = PHYS_TO_VM_PAGE(ptetemp); 2702 *dst_pte = ptetemp & ~(PG_M | PG_A); 2703 dst_pmap->pm_stats.resident_count++; 2704 pmap_insert_entry(dst_pmap, addr, 2705 dstmpte, m); 2706 } else { 2707 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2708 } 2709 if (dstmpte->hold_count >= srcmpte->hold_count) 2710 break; 2711 } 2712 addr += PAGE_SIZE; 2713 src_pte++; 2714 dst_pte++; 2715 } 2716 } 2717} 2718 2719#ifdef SMP 2720 2721/* 2722 * pmap_zpi_switchin*() 2723 * 2724 * These functions allow us to avoid doing IPIs alltogether in certain 2725 * temporary page-mapping situations (page zeroing). Instead to deal 2726 * with being preempted and moved onto a different cpu we invalidate 2727 * the page when the scheduler switches us in. This does not occur 2728 * very often so we remain relatively optimal with very little effort. 2729 */ 2730static void 2731pmap_zpi_switchin12(void) 2732{ 2733 invlpg((u_int)CADDR1); 2734 invlpg((u_int)CADDR2); 2735} 2736 2737static void 2738pmap_zpi_switchin2(void) 2739{ 2740 invlpg((u_int)CADDR2); 2741} 2742 2743static void 2744pmap_zpi_switchin3(void) 2745{ 2746 invlpg((u_int)CADDR3); 2747} 2748 2749#endif 2750 2751/* 2752 * pmap_zero_page zeros the specified hardware page by mapping 2753 * the page into KVM and using bzero to clear its contents. 2754 */ 2755void 2756pmap_zero_page(vm_page_t m) 2757{ 2758 vm_offset_t phys; 2759 2760 phys = VM_PAGE_TO_PHYS(m); 2761 if (*CMAP2) 2762 panic("pmap_zero_page: CMAP2 busy"); 2763 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2764#ifdef I386_CPU 2765 invltlb(); 2766#else 2767#ifdef SMP 2768 curthread->td_switchin = pmap_zpi_switchin2; 2769#endif 2770 invlpg((u_int)CADDR2); 2771#endif 2772#if defined(I686_CPU) 2773 if (cpu_class == CPUCLASS_686) 2774 i686_pagezero(CADDR2); 2775 else 2776#endif 2777 bzero(CADDR2, PAGE_SIZE); 2778#ifdef SMP 2779 curthread->td_switchin = NULL; 2780#endif 2781 *CMAP2 = 0; 2782} 2783 2784/* 2785 * pmap_zero_page_area zeros the specified hardware page by mapping 2786 * the page into KVM and using bzero to clear its contents. 2787 * 2788 * off and size may not cover an area beyond a single hardware page. 2789 */ 2790void 2791pmap_zero_page_area(vm_page_t m, int off, int size) 2792{ 2793 vm_offset_t phys; 2794 2795 phys = VM_PAGE_TO_PHYS(m); 2796 if (*CMAP2) 2797 panic("pmap_zero_page: CMAP2 busy"); 2798 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2799#ifdef I386_CPU 2800 invltlb(); 2801#else 2802#ifdef SMP 2803 curthread->td_switchin = pmap_zpi_switchin2; 2804#endif 2805 invlpg((u_int)CADDR2); 2806#endif 2807#if defined(I686_CPU) 2808 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2809 i686_pagezero(CADDR2); 2810 else 2811#endif 2812 bzero((char *)CADDR2 + off, size); 2813#ifdef SMP 2814 curthread->td_switchin = NULL; 2815#endif 2816 *CMAP2 = 0; 2817} 2818 2819/* 2820 * pmap_zero_page_idle zeros the specified hardware page by mapping 2821 * the page into KVM and using bzero to clear its contents. This 2822 * is intended to be called from the vm_pagezero process only and 2823 * outside of Giant. 2824 */ 2825void 2826pmap_zero_page_idle(vm_page_t m) 2827{ 2828 vm_offset_t phys; 2829 2830 phys = VM_PAGE_TO_PHYS(m); 2831 if (*CMAP3) 2832 panic("pmap_zero_page: CMAP3 busy"); 2833 *CMAP3 = PG_V | PG_RW | phys | PG_A | PG_M; 2834#ifdef I386_CPU 2835 invltlb(); 2836#else 2837#ifdef SMP 2838 curthread->td_switchin = pmap_zpi_switchin3; 2839#endif 2840 invlpg((u_int)CADDR3); 2841#endif 2842#if defined(I686_CPU) 2843 if (cpu_class == CPUCLASS_686) 2844 i686_pagezero(CADDR3); 2845 else 2846#endif 2847 bzero(CADDR3, PAGE_SIZE); 2848#ifdef SMP 2849 curthread->td_switchin = NULL; 2850#endif 2851 *CMAP3 = 0; 2852} 2853 2854/* 2855 * pmap_copy_page copies the specified (machine independent) 2856 * page by mapping the page into virtual memory and using 2857 * bcopy to copy the page, one machine dependent page at a 2858 * time. 2859 */ 2860void 2861pmap_copy_page(vm_page_t src, vm_page_t dst) 2862{ 2863 2864 if (*CMAP1) 2865 panic("pmap_copy_page: CMAP1 busy"); 2866 if (*CMAP2) 2867 panic("pmap_copy_page: CMAP2 busy"); 2868 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2869 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2870#ifdef I386_CPU 2871 invltlb(); 2872#else 2873#ifdef SMP 2874 curthread->td_switchin = pmap_zpi_switchin12; 2875#endif 2876 invlpg((u_int)CADDR1); 2877 invlpg((u_int)CADDR2); 2878#endif 2879 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2880#ifdef SMP 2881 curthread->td_switchin = NULL; 2882#endif 2883 *CMAP1 = 0; 2884 *CMAP2 = 0; 2885} 2886 2887/* 2888 * Returns true if the pmap's pv is one of the first 2889 * 16 pvs linked to from this page. This count may 2890 * be changed upwards or downwards in the future; it 2891 * is only necessary that true be returned for a small 2892 * subset of pmaps for proper page aging. 2893 */ 2894boolean_t 2895pmap_page_exists_quick(pmap, m) 2896 pmap_t pmap; 2897 vm_page_t m; 2898{ 2899 pv_entry_t pv; 2900 int loops = 0; 2901 int s; 2902 2903 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2904 return FALSE; 2905 2906 s = splvm(); 2907 2908 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2909 if (pv->pv_pmap == pmap) { 2910 splx(s); 2911 return TRUE; 2912 } 2913 loops++; 2914 if (loops >= 16) 2915 break; 2916 } 2917 splx(s); 2918 return (FALSE); 2919} 2920 2921#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2922/* 2923 * Remove all pages from specified address space 2924 * this aids process exit speeds. Also, this code 2925 * is special cased for current process only, but 2926 * can have the more generic (and slightly slower) 2927 * mode enabled. This is much faster than pmap_remove 2928 * in the case of running down an entire address space. 2929 */ 2930void 2931pmap_remove_pages(pmap, sva, eva) 2932 pmap_t pmap; 2933 vm_offset_t sva, eva; 2934{ 2935 pt_entry_t *pte, tpte; 2936 vm_page_t m; 2937 pv_entry_t pv, npv; 2938 int s; 2939 2940#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2941 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2942 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2943 return; 2944 } 2945#endif 2946 2947 s = splvm(); 2948 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2949 2950 if (pv->pv_va >= eva || pv->pv_va < sva) { 2951 npv = TAILQ_NEXT(pv, pv_plist); 2952 continue; 2953 } 2954 2955#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2956 pte = vtopte(pv->pv_va); 2957#else 2958 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2959#endif 2960 tpte = *pte; 2961 2962 if (tpte == 0) { 2963 printf("TPTE at %p IS ZERO @ VA %08x\n", 2964 pte, pv->pv_va); 2965 panic("bad pte"); 2966 } 2967 2968/* 2969 * We cannot remove wired pages from a process' mapping at this time 2970 */ 2971 if (tpte & PG_W) { 2972 npv = TAILQ_NEXT(pv, pv_plist); 2973 continue; 2974 } 2975 2976 m = PHYS_TO_VM_PAGE(tpte); 2977 KASSERT(m->phys_addr == (tpte & PG_FRAME), 2978 ("vm_page_t %p phys_addr mismatch %08x %08x", 2979 m, m->phys_addr, tpte)); 2980 2981 KASSERT(m < &vm_page_array[vm_page_array_size], 2982 ("pmap_remove_pages: bad tpte %x", tpte)); 2983 2984 pv->pv_pmap->pm_stats.resident_count--; 2985 2986 *pte = 0; 2987 2988 /* 2989 * Update the vm_page_t clean and reference bits. 2990 */ 2991 if (tpte & PG_M) { 2992 vm_page_dirty(m); 2993 } 2994 2995 npv = TAILQ_NEXT(pv, pv_plist); 2996 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 2997 2998 m->md.pv_list_count--; 2999 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3000 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 3001 vm_page_flag_clear(m, PG_WRITEABLE); 3002 } 3003 3004 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 3005 free_pv_entry(pv); 3006 } 3007 splx(s); 3008 pmap_invalidate_all(pmap); 3009} 3010 3011/* 3012 * pmap_testbit tests bits in pte's 3013 * note that the testbit/changebit routines are inline, 3014 * and a lot of things compile-time evaluate. 3015 */ 3016static boolean_t 3017pmap_testbit(m, bit) 3018 vm_page_t m; 3019 int bit; 3020{ 3021 pv_entry_t pv; 3022 pt_entry_t *pte; 3023 int s; 3024 3025 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3026 return FALSE; 3027 3028 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 3029 return FALSE; 3030 3031 s = splvm(); 3032 3033 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3034 /* 3035 * if the bit being tested is the modified bit, then 3036 * mark clean_map and ptes as never 3037 * modified. 3038 */ 3039 if (bit & (PG_A|PG_M)) { 3040 if (!pmap_track_modified(pv->pv_va)) 3041 continue; 3042 } 3043 3044#if defined(PMAP_DIAGNOSTIC) 3045 if (!pv->pv_pmap) { 3046 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3047 continue; 3048 } 3049#endif 3050 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3051 if (*pte & bit) { 3052 splx(s); 3053 return TRUE; 3054 } 3055 } 3056 splx(s); 3057 return (FALSE); 3058} 3059 3060/* 3061 * this routine is used to modify bits in ptes 3062 */ 3063static __inline void 3064pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3065{ 3066 register pv_entry_t pv; 3067 register pt_entry_t *pte; 3068 int s; 3069 3070 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 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 splx(s); 3116} 3117 3118/* 3119 * pmap_page_protect: 3120 * 3121 * Lower the permission for all mappings to a given page. 3122 */ 3123void 3124pmap_page_protect(vm_page_t m, vm_prot_t prot) 3125{ 3126 if ((prot & VM_PROT_WRITE) == 0) { 3127 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3128 pmap_changebit(m, PG_RW, FALSE); 3129 } else { 3130 pmap_remove_all(m); 3131 } 3132 } 3133} 3134 3135vm_offset_t 3136pmap_phys_address(ppn) 3137 int ppn; 3138{ 3139 return (i386_ptob(ppn)); 3140} 3141 3142/* 3143 * pmap_ts_referenced: 3144 * 3145 * Return a count of reference bits for a page, clearing those bits. 3146 * It is not necessary for every reference bit to be cleared, but it 3147 * is necessary that 0 only be returned when there are truly no 3148 * reference bits set. 3149 * 3150 * XXX: The exact number of bits to check and clear is a matter that 3151 * should be tested and standardized at some point in the future for 3152 * optimal aging of shared pages. 3153 */ 3154int 3155pmap_ts_referenced(vm_page_t m) 3156{ 3157 register pv_entry_t pv, pvf, pvn; 3158 pt_entry_t *pte; 3159 int s; 3160 int rtval = 0; 3161 3162 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3163 return (rtval); 3164 3165 s = splvm(); 3166 3167 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3168 3169 pvf = pv; 3170 3171 do { 3172 pvn = TAILQ_NEXT(pv, pv_list); 3173 3174 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3175 3176 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3177 3178 if (!pmap_track_modified(pv->pv_va)) 3179 continue; 3180 3181 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3182 3183 if (pte && (*pte & PG_A)) { 3184 *pte &= ~PG_A; 3185 3186 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3187 3188 rtval++; 3189 if (rtval > 4) { 3190 break; 3191 } 3192 } 3193 } while ((pv = pvn) != NULL && pv != pvf); 3194 } 3195 splx(s); 3196 3197 return (rtval); 3198} 3199 3200/* 3201 * pmap_is_modified: 3202 * 3203 * Return whether or not the specified physical page was modified 3204 * in any physical maps. 3205 */ 3206boolean_t 3207pmap_is_modified(vm_page_t m) 3208{ 3209 return pmap_testbit(m, PG_M); 3210} 3211 3212/* 3213 * Clear the modify bits on the specified physical page. 3214 */ 3215void 3216pmap_clear_modify(vm_page_t m) 3217{ 3218 pmap_changebit(m, PG_M, FALSE); 3219} 3220 3221/* 3222 * pmap_clear_reference: 3223 * 3224 * Clear the reference bit on the specified physical page. 3225 */ 3226void 3227pmap_clear_reference(vm_page_t m) 3228{ 3229 pmap_changebit(m, PG_A, FALSE); 3230} 3231 3232/* 3233 * Miscellaneous support routines follow 3234 */ 3235 3236static void 3237i386_protection_init() 3238{ 3239 register int *kp, prot; 3240 3241 kp = protection_codes; 3242 for (prot = 0; prot < 8; prot++) { 3243 switch (prot) { 3244 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3245 /* 3246 * Read access is also 0. There isn't any execute bit, 3247 * so just make it readable. 3248 */ 3249 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3250 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3251 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3252 *kp++ = 0; 3253 break; 3254 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3255 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3256 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3257 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3258 *kp++ = PG_RW; 3259 break; 3260 } 3261 } 3262} 3263 3264/* 3265 * Map a set of physical memory pages into the kernel virtual 3266 * address space. Return a pointer to where it is mapped. This 3267 * routine is intended to be used for mapping device memory, 3268 * NOT real memory. 3269 */ 3270void * 3271pmap_mapdev(pa, size) 3272 vm_offset_t pa; 3273 vm_size_t size; 3274{ 3275 vm_offset_t va, tmpva, offset; 3276 pt_entry_t *pte; 3277 3278 offset = pa & PAGE_MASK; 3279 size = roundup(offset + size, PAGE_SIZE); 3280 3281 GIANT_REQUIRED; 3282 3283 va = kmem_alloc_pageable(kernel_map, size); 3284 if (!va) 3285 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3286 3287 pa = pa & PG_FRAME; 3288 for (tmpva = va; size > 0; ) { 3289 pte = vtopte(tmpva); 3290 *pte = pa | PG_RW | PG_V | pgeflag; 3291 size -= PAGE_SIZE; 3292 tmpva += PAGE_SIZE; 3293 pa += PAGE_SIZE; 3294 } 3295 pmap_invalidate_range(kernel_pmap, va, tmpva); 3296 return ((void *)(va + offset)); 3297} 3298 3299void 3300pmap_unmapdev(va, size) 3301 vm_offset_t va; 3302 vm_size_t size; 3303{ 3304 vm_offset_t base, offset, tmpva; 3305 pt_entry_t *pte; 3306 3307 base = va & PG_FRAME; 3308 offset = va & PAGE_MASK; 3309 size = roundup(offset + size, PAGE_SIZE); 3310 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE) { 3311 pte = vtopte(tmpva); 3312 *pte = 0; 3313 } 3314 pmap_invalidate_range(kernel_pmap, va, tmpva); 3315 kmem_free(kernel_map, base, size); 3316} 3317 3318/* 3319 * perform the pmap work for mincore 3320 */ 3321int 3322pmap_mincore(pmap, addr) 3323 pmap_t pmap; 3324 vm_offset_t addr; 3325{ 3326 pt_entry_t *ptep, pte; 3327 vm_page_t m; 3328 int val = 0; 3329 3330 ptep = pmap_pte(pmap, addr); 3331 if (ptep == 0) { 3332 return 0; 3333 } 3334 3335 if ((pte = *ptep) != 0) { 3336 vm_offset_t pa; 3337 3338 val = MINCORE_INCORE; 3339 if ((pte & PG_MANAGED) == 0) 3340 return val; 3341 3342 pa = pte & PG_FRAME; 3343 3344 m = PHYS_TO_VM_PAGE(pa); 3345 3346 /* 3347 * Modified by us 3348 */ 3349 if (pte & PG_M) 3350 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3351 /* 3352 * Modified by someone 3353 */ 3354 else if (m->dirty || pmap_is_modified(m)) 3355 val |= MINCORE_MODIFIED_OTHER; 3356 /* 3357 * Referenced by us 3358 */ 3359 if (pte & PG_A) 3360 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3361 3362 /* 3363 * Referenced by someone 3364 */ 3365 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3366 val |= MINCORE_REFERENCED_OTHER; 3367 vm_page_flag_set(m, PG_REFERENCED); 3368 } 3369 } 3370 return val; 3371} 3372 3373void 3374pmap_activate(struct thread *td) 3375{ 3376 struct proc *p = td->td_proc; 3377 pmap_t pmap; 3378 u_int32_t cr3; 3379 3380 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3381#if defined(SMP) 3382 pmap->pm_active |= PCPU_GET(cpumask); 3383#else 3384 pmap->pm_active |= 1; 3385#endif 3386 cr3 = vtophys(pmap->pm_pdir); 3387 /* XXXKSE this is wrong. 3388 * pmap_activate is for the current thread on the current cpu 3389 */ 3390 if (p->p_flag & P_KSES) { 3391 /* Make sure all other cr3 entries are updated. */ 3392 /* what if they are running? XXXKSE (maybe abort them) */ 3393 FOREACH_THREAD_IN_PROC(p, td) { 3394 td->td_pcb->pcb_cr3 = cr3; 3395 } 3396 } else { 3397 td->td_pcb->pcb_cr3 = cr3; 3398 } 3399 load_cr3(cr3); 3400#ifdef SWTCH_OPTIM_STATS 3401 tlb_flush_count++; 3402#endif 3403} 3404 3405vm_offset_t 3406pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3407{ 3408 3409 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3410 return addr; 3411 } 3412 3413 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3414 return addr; 3415} 3416 3417 3418#if defined(PMAP_DEBUG) 3419pmap_pid_dump(int pid) 3420{ 3421 pmap_t pmap; 3422 struct proc *p; 3423 int npte = 0; 3424 int index; 3425 3426 sx_slock(&allproc_lock); 3427 LIST_FOREACH(p, &allproc, p_list) { 3428 if (p->p_pid != pid) 3429 continue; 3430 3431 if (p->p_vmspace) { 3432 int i,j; 3433 index = 0; 3434 pmap = vmspace_pmap(p->p_vmspace); 3435 for (i = 0; i < NPDEPG; i++) { 3436 pd_entry_t *pde; 3437 pt_entry_t *pte; 3438 vm_offset_t base = i << PDRSHIFT; 3439 3440 pde = &pmap->pm_pdir[i]; 3441 if (pde && pmap_pde_v(pde)) { 3442 for (j = 0; j < NPTEPG; j++) { 3443 vm_offset_t va = base + (j << PAGE_SHIFT); 3444 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3445 if (index) { 3446 index = 0; 3447 printf("\n"); 3448 } 3449 sx_sunlock(&allproc_lock); 3450 return npte; 3451 } 3452 pte = pmap_pte_quick(pmap, va); 3453 if (pte && pmap_pte_v(pte)) { 3454 pt_entry_t pa; 3455 vm_page_t m; 3456 pa = *pte; 3457 m = PHYS_TO_VM_PAGE(pa); 3458 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3459 va, pa, m->hold_count, m->wire_count, m->flags); 3460 npte++; 3461 index++; 3462 if (index >= 2) { 3463 index = 0; 3464 printf("\n"); 3465 } else { 3466 printf(" "); 3467 } 3468 } 3469 } 3470 } 3471 } 3472 } 3473 } 3474 sx_sunlock(&allproc_lock); 3475 return npte; 3476} 3477#endif 3478 3479#if defined(DEBUG) 3480 3481static void pads(pmap_t pm); 3482void pmap_pvdump(vm_offset_t pa); 3483 3484/* print address space of pmap*/ 3485static void 3486pads(pm) 3487 pmap_t pm; 3488{ 3489 int i, j; 3490 vm_offset_t va; 3491 pt_entry_t *ptep; 3492 3493 if (pm == kernel_pmap) 3494 return; 3495 for (i = 0; i < NPDEPG; i++) 3496 if (pm->pm_pdir[i]) 3497 for (j = 0; j < NPTEPG; j++) { 3498 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3499 if (pm == kernel_pmap && va < KERNBASE) 3500 continue; 3501 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3502 continue; 3503 ptep = pmap_pte_quick(pm, va); 3504 if (pmap_pte_v(ptep)) 3505 printf("%x:%x ", va, *ptep); 3506 }; 3507 3508} 3509 3510void 3511pmap_pvdump(pa) 3512 vm_offset_t pa; 3513{ 3514 pv_entry_t pv; 3515 vm_page_t m; 3516 3517 printf("pa %x", pa); 3518 m = PHYS_TO_VM_PAGE(pa); 3519 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3520 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3521 pads(pv->pv_pmap); 3522 } 3523 printf(" "); 3524} 3525#endif 3526