pmap.c revision 100912
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 100912 2002-07-30 06:45:39Z 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 469void * 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 && vm_page_sleep_busy(m, FALSE, "pplookp")) 929 goto retry; 930 return m; 931} 932 933/* 934 * Create the kernel stack (including pcb for i386) for a new thread. 935 * This routine directly affects the fork perf for a process and 936 * create performance for a thread. 937 */ 938void 939pmap_new_thread(struct thread *td) 940{ 941 int i; 942 vm_page_t ma[KSTACK_PAGES]; 943 vm_object_t ksobj; 944 vm_page_t m; 945 vm_offset_t ks; 946 947 /* 948 * allocate object for the kstack 949 */ 950 ksobj = vm_object_allocate(OBJT_DEFAULT, KSTACK_PAGES); 951 td->td_kstack_obj = ksobj; 952 953 /* get a kernel virtual address for the kstack for this thread */ 954#ifdef KSTACK_GUARD 955 ks = kmem_alloc_nofault(kernel_map, (KSTACK_PAGES + 1) * PAGE_SIZE); 956 if (ks == 0) 957 panic("pmap_new_thread: kstack allocation failed"); 958 if (*vtopte(ks) != 0) 959 pmap_qremove(ks, 1); 960 ks += PAGE_SIZE; 961 td->td_kstack = ks; 962#else 963 /* get a kernel virtual address for the kstack for this thread */ 964 ks = kmem_alloc_nofault(kernel_map, KSTACK_PAGES * PAGE_SIZE); 965 if (ks == 0) 966 panic("pmap_new_thread: kstack allocation failed"); 967 td->td_kstack = ks; 968#endif 969 /* 970 * For the length of the stack, link in a real page of ram for each 971 * page of stack. 972 */ 973 for (i = 0; i < KSTACK_PAGES; i++) { 974 /* 975 * Get a kernel stack page 976 */ 977 m = vm_page_grab(ksobj, i, 978 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED); 979 ma[i] = m; 980 981 vm_page_wakeup(m); 982 vm_page_flag_clear(m, PG_ZERO); 983 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 984 m->valid = VM_PAGE_BITS_ALL; 985 } 986 pmap_qenter(ks, ma, KSTACK_PAGES); 987} 988 989/* 990 * Dispose the kernel stack for a thread that has exited. 991 * This routine directly impacts the exit perf of a process and thread. 992 */ 993void 994pmap_dispose_thread(td) 995 struct thread *td; 996{ 997 int i; 998 vm_object_t ksobj; 999 vm_offset_t ks; 1000 vm_page_t m; 1001 1002 ksobj = td->td_kstack_obj; 1003 ks = td->td_kstack; 1004 pmap_qremove(ks, KSTACK_PAGES); 1005 for (i = 0; i < KSTACK_PAGES; i++) { 1006 m = vm_page_lookup(ksobj, i); 1007 if (m == NULL) 1008 panic("pmap_dispose_thread: kstack already missing?"); 1009 vm_page_lock_queues(); 1010 vm_page_busy(m); 1011 vm_page_unwire(m, 0); 1012 vm_page_free(m); 1013 vm_page_unlock_queues(); 1014 } 1015 /* 1016 * Free the space that this stack was mapped to in the kernel 1017 * address map. 1018 */ 1019#ifdef KSTACK_GUARD 1020 kmem_free(kernel_map, ks - PAGE_SIZE, (KSTACK_PAGES + 1) * PAGE_SIZE); 1021#else 1022 kmem_free(kernel_map, ks, KSTACK_PAGES * PAGE_SIZE); 1023#endif 1024 vm_object_deallocate(ksobj); 1025} 1026 1027/* 1028 * Allow the Kernel stack for a thread to be prejudicially paged out. 1029 */ 1030void 1031pmap_swapout_thread(td) 1032 struct thread *td; 1033{ 1034 int i; 1035 vm_object_t ksobj; 1036 vm_offset_t ks; 1037 vm_page_t m; 1038 1039 ksobj = td->td_kstack_obj; 1040 ks = td->td_kstack; 1041 pmap_qremove(ks, KSTACK_PAGES); 1042 for (i = 0; i < KSTACK_PAGES; i++) { 1043 m = vm_page_lookup(ksobj, i); 1044 if (m == NULL) 1045 panic("pmap_swapout_thread: kstack already missing?"); 1046 vm_page_lock_queues(); 1047 vm_page_dirty(m); 1048 vm_page_unwire(m, 0); 1049 vm_page_unlock_queues(); 1050 } 1051} 1052 1053/* 1054 * Bring the kernel stack for a specified thread back in. 1055 */ 1056void 1057pmap_swapin_thread(td) 1058 struct thread *td; 1059{ 1060 int i, rv; 1061 vm_page_t ma[KSTACK_PAGES]; 1062 vm_object_t ksobj; 1063 vm_offset_t ks; 1064 vm_page_t m; 1065 1066 ksobj = td->td_kstack_obj; 1067 ks = td->td_kstack; 1068 for (i = 0; i < KSTACK_PAGES; i++) { 1069 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1070 if (m->valid != VM_PAGE_BITS_ALL) { 1071 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1072 if (rv != VM_PAGER_OK) 1073 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1074 m = vm_page_lookup(ksobj, i); 1075 m->valid = VM_PAGE_BITS_ALL; 1076 } 1077 ma[i] = m; 1078 vm_page_lock_queues(); 1079 vm_page_wire(m); 1080 vm_page_wakeup(m); 1081 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 1082 vm_page_unlock_queues(); 1083 } 1084 pmap_qenter(ks, ma, KSTACK_PAGES); 1085} 1086 1087/*************************************************** 1088 * Page table page management routines..... 1089 ***************************************************/ 1090 1091/* 1092 * This routine unholds page table pages, and if the hold count 1093 * drops to zero, then it decrements the wire count. 1094 */ 1095static int 1096_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1097{ 1098 1099 while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) 1100 ; 1101 1102 if (m->hold_count == 0) { 1103 vm_offset_t pteva; 1104 /* 1105 * unmap the page table page 1106 */ 1107 pmap->pm_pdir[m->pindex] = 0; 1108 --pmap->pm_stats.resident_count; 1109 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1110 (PTDpde & PG_FRAME)) { 1111 /* 1112 * Do a invltlb to make the invalidated mapping 1113 * take effect immediately. 1114 */ 1115 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); 1116 pmap_invalidate_page(pmap, pteva); 1117 } 1118 1119 if (pmap->pm_ptphint == m) 1120 pmap->pm_ptphint = NULL; 1121 1122 /* 1123 * If the page is finally unwired, simply free it. 1124 */ 1125 --m->wire_count; 1126 if (m->wire_count == 0) { 1127 1128 vm_page_flash(m); 1129 vm_page_busy(m); 1130 vm_page_free_zero(m); 1131 --cnt.v_wire_count; 1132 } 1133 return 1; 1134 } 1135 return 0; 1136} 1137 1138static PMAP_INLINE int 1139pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1140{ 1141 vm_page_unhold(m); 1142 if (m->hold_count == 0) 1143 return _pmap_unwire_pte_hold(pmap, m); 1144 else 1145 return 0; 1146} 1147 1148/* 1149 * After removing a page table entry, this routine is used to 1150 * conditionally free the page, and manage the hold/wire counts. 1151 */ 1152static int 1153pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1154{ 1155 unsigned ptepindex; 1156 if (va >= VM_MAXUSER_ADDRESS) 1157 return 0; 1158 1159 if (mpte == NULL) { 1160 ptepindex = (va >> PDRSHIFT); 1161 if (pmap->pm_ptphint && 1162 (pmap->pm_ptphint->pindex == ptepindex)) { 1163 mpte = pmap->pm_ptphint; 1164 } else { 1165 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1166 pmap->pm_ptphint = mpte; 1167 } 1168 } 1169 1170 return pmap_unwire_pte_hold(pmap, mpte); 1171} 1172 1173void 1174pmap_pinit0(pmap) 1175 struct pmap *pmap; 1176{ 1177 pmap->pm_pdir = 1178 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1179 pmap_kenter((vm_offset_t)pmap->pm_pdir, (vm_offset_t)IdlePTD); 1180#ifndef I386_CPU 1181 invlpg((vm_offset_t)pmap->pm_pdir); 1182#else 1183 invltlb(); 1184#endif 1185 pmap->pm_ptphint = NULL; 1186 pmap->pm_active = 0; 1187 TAILQ_INIT(&pmap->pm_pvlist); 1188 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1189 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1190} 1191 1192/* 1193 * Initialize a preallocated and zeroed pmap structure, 1194 * such as one in a vmspace structure. 1195 */ 1196void 1197pmap_pinit(pmap) 1198 register struct pmap *pmap; 1199{ 1200 vm_page_t ptdpg; 1201 1202 /* 1203 * No need to allocate page table space yet but we do need a valid 1204 * page directory table. 1205 */ 1206 if (pmap->pm_pdir == NULL) 1207 pmap->pm_pdir = 1208 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1209 1210 /* 1211 * allocate object for the ptes 1212 */ 1213 if (pmap->pm_pteobj == NULL) 1214 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1215 1216 /* 1217 * allocate the page directory page 1218 */ 1219 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1220 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED); 1221 vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/ 1222 ptdpg->valid = VM_PAGE_BITS_ALL; 1223 1224 pmap_qenter((vm_offset_t) pmap->pm_pdir, &ptdpg, 1); 1225 if ((ptdpg->flags & PG_ZERO) == 0) 1226 bzero(pmap->pm_pdir, PAGE_SIZE); 1227 1228 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1229 /* Wire in kernel global address entries. */ 1230 /* XXX copies current process, does not fill in MPPTDI */ 1231 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1232#ifdef SMP 1233 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1234#endif 1235 1236 /* install self-referential address mapping entry */ 1237 pmap->pm_pdir[PTDPTDI] = 1238 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1239 1240 pmap->pm_active = 0; 1241 pmap->pm_ptphint = NULL; 1242 TAILQ_INIT(&pmap->pm_pvlist); 1243 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1244} 1245 1246/* 1247 * Wire in kernel global address entries. To avoid a race condition 1248 * between pmap initialization and pmap_growkernel, this procedure 1249 * should be called after the vmspace is attached to the process 1250 * but before this pmap is activated. 1251 */ 1252void 1253pmap_pinit2(pmap) 1254 struct pmap *pmap; 1255{ 1256 /* XXX: Remove this stub when no longer called */ 1257} 1258 1259static int 1260pmap_release_free_page(pmap_t pmap, vm_page_t p) 1261{ 1262 pd_entry_t *pde = pmap->pm_pdir; 1263 /* 1264 * This code optimizes the case of freeing non-busy 1265 * page-table pages. Those pages are zero now, and 1266 * might as well be placed directly into the zero queue. 1267 */ 1268 if (vm_page_sleep_busy(p, FALSE, "pmaprl")) 1269 return 0; 1270 1271 vm_page_lock_queues(); 1272 vm_page_busy(p); 1273 1274 /* 1275 * Remove the page table page from the processes address space. 1276 */ 1277 pde[p->pindex] = 0; 1278 pmap->pm_stats.resident_count--; 1279 1280 if (p->hold_count) { 1281 panic("pmap_release: freeing held page table page"); 1282 } 1283 /* 1284 * Page directory pages need to have the kernel 1285 * stuff cleared, so they can go into the zero queue also. 1286 */ 1287 if (p->pindex == PTDPTDI) { 1288 bzero(pde + KPTDI, nkpt * PTESIZE); 1289#ifdef SMP 1290 pde[MPPTDI] = 0; 1291#endif 1292 pde[APTDPTDI] = 0; 1293 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1294 } 1295 1296 if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex)) 1297 pmap->pm_ptphint = NULL; 1298 1299 p->wire_count--; 1300 cnt.v_wire_count--; 1301 vm_page_free_zero(p); 1302 vm_page_unlock_queues(); 1303 return 1; 1304} 1305 1306/* 1307 * this routine is called if the page table page is not 1308 * mapped correctly. 1309 */ 1310static vm_page_t 1311_pmap_allocpte(pmap, ptepindex) 1312 pmap_t pmap; 1313 unsigned ptepindex; 1314{ 1315 vm_offset_t pteva, ptepa; /* XXXPA */ 1316 vm_page_t m; 1317 1318 /* 1319 * Find or fabricate a new pagetable page 1320 */ 1321 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1322 VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1323 1324 KASSERT(m->queue == PQ_NONE, 1325 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1326 1327 if (m->wire_count == 0) 1328 cnt.v_wire_count++; 1329 m->wire_count++; 1330 1331 /* 1332 * Increment the hold count for the page table page 1333 * (denoting a new mapping.) 1334 */ 1335 m->hold_count++; 1336 1337 /* 1338 * Map the pagetable page into the process address space, if 1339 * it isn't already there. 1340 */ 1341 1342 pmap->pm_stats.resident_count++; 1343 1344 ptepa = VM_PAGE_TO_PHYS(m); 1345 pmap->pm_pdir[ptepindex] = 1346 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1347 1348 /* 1349 * Set the page table hint 1350 */ 1351 pmap->pm_ptphint = m; 1352 1353 /* 1354 * Try to use the new mapping, but if we cannot, then 1355 * do it with the routine that maps the page explicitly. 1356 */ 1357 if ((m->flags & PG_ZERO) == 0) { 1358 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1359 (PTDpde & PG_FRAME)) { 1360 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1361 bzero((caddr_t) pteva, PAGE_SIZE); 1362 } else { 1363 pmap_zero_page(m); 1364 } 1365 } 1366 1367 m->valid = VM_PAGE_BITS_ALL; 1368 vm_page_flag_clear(m, PG_ZERO); 1369 vm_page_flag_set(m, PG_MAPPED); 1370 vm_page_wakeup(m); 1371 1372 return m; 1373} 1374 1375static vm_page_t 1376pmap_allocpte(pmap_t pmap, vm_offset_t va) 1377{ 1378 unsigned ptepindex; 1379 pd_entry_t ptepa; 1380 vm_page_t m; 1381 1382 /* 1383 * Calculate pagetable page index 1384 */ 1385 ptepindex = va >> PDRSHIFT; 1386 1387 /* 1388 * Get the page directory entry 1389 */ 1390 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1391 1392 /* 1393 * This supports switching from a 4MB page to a 1394 * normal 4K page. 1395 */ 1396 if (ptepa & PG_PS) { 1397 pmap->pm_pdir[ptepindex] = 0; 1398 ptepa = 0; 1399 pmap_invalidate_all(kernel_pmap); 1400 } 1401 1402 /* 1403 * If the page table page is mapped, we just increment the 1404 * hold count, and activate it. 1405 */ 1406 if (ptepa) { 1407 /* 1408 * In order to get the page table page, try the 1409 * hint first. 1410 */ 1411 if (pmap->pm_ptphint && 1412 (pmap->pm_ptphint->pindex == ptepindex)) { 1413 m = pmap->pm_ptphint; 1414 } else { 1415 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1416 pmap->pm_ptphint = m; 1417 } 1418 m->hold_count++; 1419 return m; 1420 } 1421 /* 1422 * Here if the pte page isn't mapped, or if it has been deallocated. 1423 */ 1424 return _pmap_allocpte(pmap, ptepindex); 1425} 1426 1427 1428/*************************************************** 1429* Pmap allocation/deallocation routines. 1430 ***************************************************/ 1431 1432/* 1433 * Release any resources held by the given physical map. 1434 * Called when a pmap initialized by pmap_pinit is being released. 1435 * Should only be called if the map contains no valid mappings. 1436 */ 1437void 1438pmap_release(pmap_t pmap) 1439{ 1440 vm_page_t p,n,ptdpg; 1441 vm_object_t object = pmap->pm_pteobj; 1442 int curgeneration; 1443 1444#if defined(DIAGNOSTIC) 1445 if (object->ref_count != 1) 1446 panic("pmap_release: pteobj reference count != 1"); 1447#endif 1448 1449 ptdpg = NULL; 1450 LIST_REMOVE(pmap, pm_list); 1451retry: 1452 curgeneration = object->generation; 1453 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1454 n = TAILQ_NEXT(p, listq); 1455 if (p->pindex == PTDPTDI) { 1456 ptdpg = p; 1457 continue; 1458 } 1459 while (1) { 1460 if (!pmap_release_free_page(pmap, p) && 1461 (object->generation != curgeneration)) 1462 goto retry; 1463 } 1464 } 1465 1466 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1467 goto retry; 1468} 1469 1470static int 1471kvm_size(SYSCTL_HANDLER_ARGS) 1472{ 1473 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1474 1475 return sysctl_handle_long(oidp, &ksize, 0, req); 1476} 1477SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1478 0, 0, kvm_size, "IU", "Size of KVM"); 1479 1480static int 1481kvm_free(SYSCTL_HANDLER_ARGS) 1482{ 1483 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1484 1485 return sysctl_handle_long(oidp, &kfree, 0, req); 1486} 1487SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1488 0, 0, kvm_free, "IU", "Amount of KVM free"); 1489 1490/* 1491 * grow the number of kernel page table entries, if needed 1492 */ 1493void 1494pmap_growkernel(vm_offset_t addr) 1495{ 1496 struct pmap *pmap; 1497 int s; 1498 vm_offset_t ptppaddr; 1499 vm_page_t nkpg; 1500 pd_entry_t newpdir; 1501 1502 s = splhigh(); 1503 if (kernel_vm_end == 0) { 1504 kernel_vm_end = KERNBASE; 1505 nkpt = 0; 1506 while (pdir_pde(PTD, kernel_vm_end)) { 1507 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1508 nkpt++; 1509 } 1510 } 1511 addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1512 while (kernel_vm_end < addr) { 1513 if (pdir_pde(PTD, kernel_vm_end)) { 1514 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1515 continue; 1516 } 1517 1518 /* 1519 * This index is bogus, but out of the way 1520 */ 1521 nkpg = vm_page_alloc(kptobj, nkpt, 1522 VM_ALLOC_SYSTEM | VM_ALLOC_WIRED); 1523 if (!nkpg) 1524 panic("pmap_growkernel: no memory to grow kernel"); 1525 1526 nkpt++; 1527 1528 pmap_zero_page(nkpg); 1529 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1530 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1531 pdir_pde(PTD, kernel_vm_end) = newpdir; 1532 1533 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1534 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1535 } 1536 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1537 } 1538 splx(s); 1539} 1540 1541 1542/*************************************************** 1543 * page management routines. 1544 ***************************************************/ 1545 1546/* 1547 * free the pv_entry back to the free list 1548 */ 1549static PMAP_INLINE void 1550free_pv_entry(pv_entry_t pv) 1551{ 1552 pv_entry_count--; 1553 uma_zfree(pvzone, pv); 1554} 1555 1556/* 1557 * get a new pv_entry, allocating a block from the system 1558 * when needed. 1559 * the memory allocation is performed bypassing the malloc code 1560 * because of the possibility of allocations at interrupt time. 1561 */ 1562static pv_entry_t 1563get_pv_entry(void) 1564{ 1565 pv_entry_count++; 1566 if (pv_entry_high_water && 1567 (pv_entry_count > pv_entry_high_water) && 1568 (pmap_pagedaemon_waken == 0)) { 1569 pmap_pagedaemon_waken = 1; 1570 wakeup (&vm_pages_needed); 1571 } 1572 return uma_zalloc(pvzone, M_NOWAIT); 1573} 1574 1575/* 1576 * This routine is very drastic, but can save the system 1577 * in a pinch. 1578 */ 1579void 1580pmap_collect() 1581{ 1582 int i; 1583 vm_page_t m; 1584 static int warningdone = 0; 1585 1586 if (pmap_pagedaemon_waken == 0) 1587 return; 1588 1589 if (warningdone < 5) { 1590 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1591 warningdone++; 1592 } 1593 1594 for(i = 0; i < vm_page_array_size; i++) { 1595 m = &vm_page_array[i]; 1596 if (m->wire_count || m->hold_count || m->busy || 1597 (m->flags & (PG_BUSY | PG_UNMANAGED))) 1598 continue; 1599 pmap_remove_all(m); 1600 } 1601 pmap_pagedaemon_waken = 0; 1602} 1603 1604 1605/* 1606 * If it is the first entry on the list, it is actually 1607 * in the header and we must copy the following entry up 1608 * to the header. Otherwise we must search the list for 1609 * the entry. In either case we free the now unused entry. 1610 */ 1611 1612static int 1613pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1614{ 1615 pv_entry_t pv; 1616 int rtval; 1617 int s; 1618 1619 s = splvm(); 1620 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1621 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1622 if (pmap == pv->pv_pmap && va == pv->pv_va) 1623 break; 1624 } 1625 } else { 1626 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1627 if (va == pv->pv_va) 1628 break; 1629 } 1630 } 1631 1632 rtval = 0; 1633 if (pv) { 1634 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1635 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1636 m->md.pv_list_count--; 1637 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1638 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1639 1640 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1641 free_pv_entry(pv); 1642 } 1643 1644 splx(s); 1645 return rtval; 1646} 1647 1648/* 1649 * Create a pv entry for page at pa for 1650 * (pmap, va). 1651 */ 1652static void 1653pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1654{ 1655 1656 int s; 1657 pv_entry_t pv; 1658 1659 s = splvm(); 1660 pv = get_pv_entry(); 1661 pv->pv_va = va; 1662 pv->pv_pmap = pmap; 1663 pv->pv_ptem = mpte; 1664 1665 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1666 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1667 m->md.pv_list_count++; 1668 1669 splx(s); 1670} 1671 1672/* 1673 * pmap_remove_pte: do the things to unmap a page in a process 1674 */ 1675static int 1676pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1677{ 1678 pt_entry_t oldpte; 1679 vm_page_t m; 1680 1681 oldpte = atomic_readandclear_int(ptq); 1682 if (oldpte & PG_W) 1683 pmap->pm_stats.wired_count -= 1; 1684 /* 1685 * Machines that don't support invlpg, also don't support 1686 * PG_G. 1687 */ 1688 if (oldpte & PG_G) 1689 pmap_invalidate_page(kernel_pmap, va); 1690 pmap->pm_stats.resident_count -= 1; 1691 if (oldpte & PG_MANAGED) { 1692 m = PHYS_TO_VM_PAGE(oldpte); 1693 if (oldpte & PG_M) { 1694#if defined(PMAP_DIAGNOSTIC) 1695 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1696 printf( 1697 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1698 va, oldpte); 1699 } 1700#endif 1701 if (pmap_track_modified(va)) 1702 vm_page_dirty(m); 1703 } 1704 if (oldpte & PG_A) 1705 vm_page_flag_set(m, PG_REFERENCED); 1706 return pmap_remove_entry(pmap, m, va); 1707 } else { 1708 return pmap_unuse_pt(pmap, va, NULL); 1709 } 1710 1711 return 0; 1712} 1713 1714/* 1715 * Remove a single page from a process address space 1716 */ 1717static void 1718pmap_remove_page(pmap_t pmap, vm_offset_t va) 1719{ 1720 register pt_entry_t *ptq; 1721 1722 /* 1723 * if there is no pte for this address, just skip it!!! 1724 */ 1725 if (*pmap_pde(pmap, va) == 0) { 1726 return; 1727 } 1728 1729 /* 1730 * get a local va for mappings for this pmap. 1731 */ 1732 ptq = get_ptbase(pmap) + i386_btop(va); 1733 if (*ptq) { 1734 (void) pmap_remove_pte(pmap, ptq, va); 1735 pmap_invalidate_page(pmap, va); 1736 } 1737 return; 1738} 1739 1740/* 1741 * Remove the given range of addresses from the specified map. 1742 * 1743 * It is assumed that the start and end are properly 1744 * rounded to the page size. 1745 */ 1746void 1747pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1748{ 1749 register pt_entry_t *ptbase; 1750 vm_offset_t pdnxt; 1751 pd_entry_t ptpaddr; 1752 vm_offset_t sindex, eindex; 1753 int anyvalid; 1754 1755 if (pmap == NULL) 1756 return; 1757 1758 if (pmap->pm_stats.resident_count == 0) 1759 return; 1760 1761 /* 1762 * special handling of removing one page. a very 1763 * common operation and easy to short circuit some 1764 * code. 1765 */ 1766 if ((sva + PAGE_SIZE == eva) && 1767 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1768 pmap_remove_page(pmap, sva); 1769 return; 1770 } 1771 1772 anyvalid = 0; 1773 1774 /* 1775 * Get a local virtual address for the mappings that are being 1776 * worked with. 1777 */ 1778 ptbase = get_ptbase(pmap); 1779 1780 sindex = i386_btop(sva); 1781 eindex = i386_btop(eva); 1782 1783 for (; sindex < eindex; sindex = pdnxt) { 1784 unsigned pdirindex; 1785 1786 /* 1787 * Calculate index for next page table. 1788 */ 1789 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1790 if (pmap->pm_stats.resident_count == 0) 1791 break; 1792 1793 pdirindex = sindex / NPDEPG; 1794 ptpaddr = pmap->pm_pdir[pdirindex]; 1795 if ((ptpaddr & PG_PS) != 0) { 1796 pmap->pm_pdir[pdirindex] = 0; 1797 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1798 anyvalid++; 1799 continue; 1800 } 1801 1802 /* 1803 * Weed out invalid mappings. Note: we assume that the page 1804 * directory table is always allocated, and in kernel virtual. 1805 */ 1806 if (ptpaddr == 0) 1807 continue; 1808 1809 /* 1810 * Limit our scan to either the end of the va represented 1811 * by the current page table page, or to the end of the 1812 * range being removed. 1813 */ 1814 if (pdnxt > eindex) { 1815 pdnxt = eindex; 1816 } 1817 1818 for (; sindex != pdnxt; sindex++) { 1819 vm_offset_t va; 1820 if (ptbase[sindex] == 0) { 1821 continue; 1822 } 1823 va = i386_ptob(sindex); 1824 1825 anyvalid++; 1826 if (pmap_remove_pte(pmap, 1827 ptbase + sindex, va)) 1828 break; 1829 } 1830 } 1831 1832 if (anyvalid) 1833 pmap_invalidate_all(pmap); 1834} 1835 1836/* 1837 * Routine: pmap_remove_all 1838 * Function: 1839 * Removes this physical page from 1840 * all physical maps in which it resides. 1841 * Reflects back modify bits to the pager. 1842 * 1843 * Notes: 1844 * Original versions of this routine were very 1845 * inefficient because they iteratively called 1846 * pmap_remove (slow...) 1847 */ 1848 1849static void 1850pmap_remove_all(vm_page_t m) 1851{ 1852 register pv_entry_t pv; 1853 pt_entry_t *pte, tpte; 1854 int s; 1855 1856#if defined(PMAP_DIAGNOSTIC) 1857 /* 1858 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1859 * pages! 1860 */ 1861 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1862 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1863 } 1864#endif 1865 1866 s = splvm(); 1867 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1868 pv->pv_pmap->pm_stats.resident_count--; 1869 1870 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1871 1872 tpte = atomic_readandclear_int(pte); 1873 if (tpte & PG_W) 1874 pv->pv_pmap->pm_stats.wired_count--; 1875 1876 if (tpte & PG_A) 1877 vm_page_flag_set(m, PG_REFERENCED); 1878 1879 /* 1880 * Update the vm_page_t clean and reference bits. 1881 */ 1882 if (tpte & PG_M) { 1883#if defined(PMAP_DIAGNOSTIC) 1884 if (pmap_nw_modified((pt_entry_t) tpte)) { 1885 printf( 1886 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1887 pv->pv_va, tpte); 1888 } 1889#endif 1890 if (pmap_track_modified(pv->pv_va)) 1891 vm_page_dirty(m); 1892 } 1893 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1894 1895 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1896 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1897 m->md.pv_list_count--; 1898 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1899 free_pv_entry(pv); 1900 } 1901 1902 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1903 1904 splx(s); 1905} 1906 1907/* 1908 * Set the physical protection on the 1909 * specified range of this map as requested. 1910 */ 1911void 1912pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1913{ 1914 register pt_entry_t *ptbase; 1915 vm_offset_t pdnxt; 1916 pd_entry_t ptpaddr; 1917 vm_offset_t sindex, eindex; 1918 int anychanged; 1919 1920 if (pmap == NULL) 1921 return; 1922 1923 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1924 pmap_remove(pmap, sva, eva); 1925 return; 1926 } 1927 1928 if (prot & VM_PROT_WRITE) 1929 return; 1930 1931 anychanged = 0; 1932 1933 ptbase = get_ptbase(pmap); 1934 1935 sindex = i386_btop(sva); 1936 eindex = i386_btop(eva); 1937 1938 for (; sindex < eindex; sindex = pdnxt) { 1939 1940 unsigned pdirindex; 1941 1942 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1943 1944 pdirindex = sindex / NPDEPG; 1945 ptpaddr = pmap->pm_pdir[pdirindex]; 1946 if ((ptpaddr & PG_PS) != 0) { 1947 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1948 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1949 anychanged++; 1950 continue; 1951 } 1952 1953 /* 1954 * Weed out invalid mappings. Note: we assume that the page 1955 * directory table is always allocated, and in kernel virtual. 1956 */ 1957 if (ptpaddr == 0) 1958 continue; 1959 1960 if (pdnxt > eindex) { 1961 pdnxt = eindex; 1962 } 1963 1964 for (; sindex != pdnxt; sindex++) { 1965 1966 pt_entry_t pbits; 1967 vm_page_t m; 1968 1969 pbits = ptbase[sindex]; 1970 1971 if (pbits & PG_MANAGED) { 1972 m = NULL; 1973 if (pbits & PG_A) { 1974 m = PHYS_TO_VM_PAGE(pbits); 1975 vm_page_flag_set(m, PG_REFERENCED); 1976 pbits &= ~PG_A; 1977 } 1978 if (pbits & PG_M) { 1979 if (pmap_track_modified(i386_ptob(sindex))) { 1980 if (m == NULL) 1981 m = PHYS_TO_VM_PAGE(pbits); 1982 vm_page_dirty(m); 1983 pbits &= ~PG_M; 1984 } 1985 } 1986 } 1987 1988 pbits &= ~PG_RW; 1989 1990 if (pbits != ptbase[sindex]) { 1991 ptbase[sindex] = pbits; 1992 anychanged = 1; 1993 } 1994 } 1995 } 1996 if (anychanged) 1997 pmap_invalidate_all(pmap); 1998} 1999 2000/* 2001 * Insert the given physical page (p) at 2002 * the specified virtual address (v) in the 2003 * target physical map with the protection requested. 2004 * 2005 * If specified, the page will be wired down, meaning 2006 * that the related pte can not be reclaimed. 2007 * 2008 * NB: This is the only routine which MAY NOT lazy-evaluate 2009 * or lose information. That is, this routine must actually 2010 * insert this page into the given map NOW. 2011 */ 2012void 2013pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2014 boolean_t wired) 2015{ 2016 vm_offset_t pa; 2017 register pt_entry_t *pte; 2018 vm_offset_t opa; 2019 pt_entry_t origpte, newpte; 2020 vm_page_t mpte; 2021 2022 if (pmap == NULL) 2023 return; 2024 2025 va &= PG_FRAME; 2026#ifdef PMAP_DIAGNOSTIC 2027 if (va > VM_MAX_KERNEL_ADDRESS) 2028 panic("pmap_enter: toobig"); 2029 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2030 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2031#endif 2032 2033 mpte = NULL; 2034 /* 2035 * In the case that a page table page is not 2036 * resident, we are creating it here. 2037 */ 2038 if (va < VM_MAXUSER_ADDRESS) { 2039 mpte = pmap_allocpte(pmap, va); 2040 } 2041#if 0 && defined(PMAP_DIAGNOSTIC) 2042 else { 2043 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2044 origpte = *pdeaddr; 2045 if ((origpte & PG_V) == 0) { 2046 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2047 pmap->pm_pdir[PTDPTDI], origpte, va); 2048 } 2049 } 2050#endif 2051 2052 pte = pmap_pte(pmap, va); 2053 2054 /* 2055 * Page Directory table entry not valid, we need a new PT page 2056 */ 2057 if (pte == NULL) { 2058 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2059 (void *)pmap->pm_pdir[PTDPTDI], va); 2060 } 2061 2062 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2063 origpte = *(vm_offset_t *)pte; 2064 opa = origpte & PG_FRAME; 2065 2066 if (origpte & PG_PS) 2067 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2068 2069 /* 2070 * Mapping has not changed, must be protection or wiring change. 2071 */ 2072 if (origpte && (opa == pa)) { 2073 /* 2074 * Wiring change, just update stats. We don't worry about 2075 * wiring PT pages as they remain resident as long as there 2076 * are valid mappings in them. Hence, if a user page is wired, 2077 * the PT page will be also. 2078 */ 2079 if (wired && ((origpte & PG_W) == 0)) 2080 pmap->pm_stats.wired_count++; 2081 else if (!wired && (origpte & PG_W)) 2082 pmap->pm_stats.wired_count--; 2083 2084#if defined(PMAP_DIAGNOSTIC) 2085 if (pmap_nw_modified((pt_entry_t) origpte)) { 2086 printf( 2087 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2088 va, origpte); 2089 } 2090#endif 2091 2092 /* 2093 * Remove extra pte reference 2094 */ 2095 if (mpte) 2096 mpte->hold_count--; 2097 2098 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2099 if ((origpte & PG_RW) == 0) { 2100 *pte |= PG_RW; 2101 pmap_invalidate_page(pmap, va); 2102 } 2103 return; 2104 } 2105 2106 /* 2107 * We might be turning off write access to the page, 2108 * so we go ahead and sense modify status. 2109 */ 2110 if (origpte & PG_MANAGED) { 2111 if ((origpte & PG_M) && pmap_track_modified(va)) { 2112 vm_page_t om; 2113 om = PHYS_TO_VM_PAGE(opa); 2114 vm_page_dirty(om); 2115 } 2116 pa |= PG_MANAGED; 2117 } 2118 goto validate; 2119 } 2120 /* 2121 * Mapping has changed, invalidate old range and fall through to 2122 * handle validating new mapping. 2123 */ 2124 if (opa) { 2125 int err; 2126 err = pmap_remove_pte(pmap, pte, va); 2127 if (err) 2128 panic("pmap_enter: pte vanished, va: 0x%x", va); 2129 } 2130 2131 /* 2132 * Enter on the PV list if part of our managed memory. Note that we 2133 * raise IPL while manipulating pv_table since pmap_enter can be 2134 * called at interrupt time. 2135 */ 2136 if (pmap_initialized && 2137 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2138 pmap_insert_entry(pmap, va, mpte, m); 2139 pa |= PG_MANAGED; 2140 } 2141 2142 /* 2143 * Increment counters 2144 */ 2145 pmap->pm_stats.resident_count++; 2146 if (wired) 2147 pmap->pm_stats.wired_count++; 2148 2149validate: 2150 /* 2151 * Now validate mapping with desired protection/wiring. 2152 */ 2153 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2154 2155 if (wired) 2156 newpte |= PG_W; 2157 if (va < VM_MAXUSER_ADDRESS) 2158 newpte |= PG_U; 2159 if (pmap == kernel_pmap) 2160 newpte |= pgeflag; 2161 2162 /* 2163 * if the mapping or permission bits are different, we need 2164 * to update the pte. 2165 */ 2166 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2167 *pte = newpte | PG_A; 2168 /*if (origpte)*/ { 2169 pmap_invalidate_page(pmap, va); 2170 } 2171 } 2172} 2173 2174/* 2175 * this code makes some *MAJOR* assumptions: 2176 * 1. Current pmap & pmap exists. 2177 * 2. Not wired. 2178 * 3. Read access. 2179 * 4. No page table pages. 2180 * 5. Tlbflush is deferred to calling procedure. 2181 * 6. Page IS managed. 2182 * but is *MUCH* faster than pmap_enter... 2183 */ 2184 2185static vm_page_t 2186pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2187{ 2188 pt_entry_t *pte; 2189 vm_offset_t pa; 2190 2191 /* 2192 * In the case that a page table page is not 2193 * resident, we are creating it here. 2194 */ 2195 if (va < VM_MAXUSER_ADDRESS) { 2196 unsigned ptepindex; 2197 pd_entry_t ptepa; 2198 2199 /* 2200 * Calculate pagetable page index 2201 */ 2202 ptepindex = va >> PDRSHIFT; 2203 if (mpte && (mpte->pindex == ptepindex)) { 2204 mpte->hold_count++; 2205 } else { 2206retry: 2207 /* 2208 * Get the page directory entry 2209 */ 2210 ptepa = pmap->pm_pdir[ptepindex]; 2211 2212 /* 2213 * If the page table page is mapped, we just increment 2214 * the hold count, and activate it. 2215 */ 2216 if (ptepa) { 2217 if (ptepa & PG_PS) 2218 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2219 if (pmap->pm_ptphint && 2220 (pmap->pm_ptphint->pindex == ptepindex)) { 2221 mpte = pmap->pm_ptphint; 2222 } else { 2223 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2224 pmap->pm_ptphint = mpte; 2225 } 2226 if (mpte == NULL) 2227 goto retry; 2228 mpte->hold_count++; 2229 } else { 2230 mpte = _pmap_allocpte(pmap, ptepindex); 2231 } 2232 } 2233 } else { 2234 mpte = NULL; 2235 } 2236 2237 /* 2238 * This call to vtopte makes the assumption that we are 2239 * entering the page into the current pmap. In order to support 2240 * quick entry into any pmap, one would likely use pmap_pte_quick. 2241 * But that isn't as quick as vtopte. 2242 */ 2243 pte = vtopte(va); 2244 if (*pte) { 2245 if (mpte) 2246 pmap_unwire_pte_hold(pmap, mpte); 2247 return 0; 2248 } 2249 2250 /* 2251 * Enter on the PV list if part of our managed memory. Note that we 2252 * raise IPL while manipulating pv_table since pmap_enter can be 2253 * called at interrupt time. 2254 */ 2255 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2256 pmap_insert_entry(pmap, va, mpte, m); 2257 2258 /* 2259 * Increment counters 2260 */ 2261 pmap->pm_stats.resident_count++; 2262 2263 pa = VM_PAGE_TO_PHYS(m); 2264 2265 /* 2266 * Now validate mapping with RO protection 2267 */ 2268 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2269 *pte = pa | PG_V | PG_U; 2270 else 2271 *pte = pa | PG_V | PG_U | PG_MANAGED; 2272 2273 return mpte; 2274} 2275 2276/* 2277 * Make a temporary mapping for a physical address. This is only intended 2278 * to be used for panic dumps. 2279 */ 2280void * 2281pmap_kenter_temporary(vm_offset_t pa, int i) 2282{ 2283 vm_offset_t va; 2284 2285 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE); 2286 pmap_kenter(va, pa); 2287#ifndef I386_CPU 2288 invlpg(va); 2289#else 2290 invltlb(); 2291#endif 2292 return ((void *)crashdumpmap); 2293} 2294 2295#define MAX_INIT_PT (96) 2296/* 2297 * pmap_object_init_pt preloads the ptes for a given object 2298 * into the specified pmap. This eliminates the blast of soft 2299 * faults on process startup and immediately after an mmap. 2300 */ 2301void 2302pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2303 vm_object_t object, vm_pindex_t pindex, 2304 vm_size_t size, int limit) 2305{ 2306 vm_offset_t tmpidx; 2307 int psize; 2308 vm_page_t p, mpte; 2309 int objpgs; 2310 2311 if (pmap == NULL || object == NULL) 2312 return; 2313 2314 /* 2315 * This code maps large physical mmap regions into the 2316 * processor address space. Note that some shortcuts 2317 * are taken, but the code works. 2318 */ 2319 if (pseflag && (object->type == OBJT_DEVICE) && 2320 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2321 int i; 2322 vm_page_t m[1]; 2323 unsigned int ptepindex; 2324 int npdes; 2325 pd_entry_t ptepa; 2326 2327 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2328 return; 2329 2330retry: 2331 p = vm_page_lookup(object, pindex); 2332 if (p && vm_page_sleep_busy(p, FALSE, "init4p")) 2333 goto retry; 2334 2335 if (p == NULL) { 2336 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2337 if (p == NULL) 2338 return; 2339 m[0] = p; 2340 2341 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2342 vm_page_lock_queues(); 2343 vm_page_free(p); 2344 vm_page_unlock_queues(); 2345 return; 2346 } 2347 2348 p = vm_page_lookup(object, pindex); 2349 vm_page_wakeup(p); 2350 } 2351 2352 ptepa = VM_PAGE_TO_PHYS(p); 2353 if (ptepa & (NBPDR - 1)) { 2354 return; 2355 } 2356 2357 p->valid = VM_PAGE_BITS_ALL; 2358 2359 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2360 npdes = size >> PDRSHIFT; 2361 for(i = 0; i < npdes; i++) { 2362 pmap->pm_pdir[ptepindex] = 2363 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2364 ptepa += NBPDR; 2365 ptepindex += 1; 2366 } 2367 vm_page_flag_set(p, PG_MAPPED); 2368 pmap_invalidate_all(kernel_pmap); 2369 return; 2370 } 2371 2372 psize = i386_btop(size); 2373 2374 if ((object->type != OBJT_VNODE) || 2375 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2376 (object->resident_page_count > MAX_INIT_PT))) { 2377 return; 2378 } 2379 2380 if (psize + pindex > object->size) { 2381 if (object->size < pindex) 2382 return; 2383 psize = object->size - pindex; 2384 } 2385 2386 mpte = NULL; 2387 /* 2388 * if we are processing a major portion of the object, then scan the 2389 * entire thing. 2390 */ 2391 if (psize > (object->resident_page_count >> 2)) { 2392 objpgs = psize; 2393 2394 for (p = TAILQ_FIRST(&object->memq); 2395 ((objpgs > 0) && (p != NULL)); 2396 p = TAILQ_NEXT(p, listq)) { 2397 2398 if (p->pindex < pindex || p->pindex - pindex >= psize) { 2399 continue; 2400 } 2401 tmpidx = p->pindex - pindex; 2402 /* 2403 * don't allow an madvise to blow away our really 2404 * free pages allocating pv entries. 2405 */ 2406 if ((limit & MAP_PREFAULT_MADVISE) && 2407 cnt.v_free_count < cnt.v_free_reserved) { 2408 break; 2409 } 2410 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2411 (p->busy == 0) && 2412 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2413 if ((p->queue - p->pc) == PQ_CACHE) 2414 vm_page_deactivate(p); 2415 vm_page_busy(p); 2416 mpte = pmap_enter_quick(pmap, 2417 addr + i386_ptob(tmpidx), p, mpte); 2418 vm_page_flag_set(p, PG_MAPPED); 2419 vm_page_wakeup(p); 2420 } 2421 objpgs -= 1; 2422 } 2423 } else { 2424 /* 2425 * else lookup the pages one-by-one. 2426 */ 2427 for (tmpidx = 0; tmpidx < psize; tmpidx += 1) { 2428 /* 2429 * don't allow an madvise to blow away our really 2430 * free pages allocating pv entries. 2431 */ 2432 if ((limit & MAP_PREFAULT_MADVISE) && 2433 cnt.v_free_count < cnt.v_free_reserved) { 2434 break; 2435 } 2436 p = vm_page_lookup(object, tmpidx + pindex); 2437 if (p && 2438 ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2439 (p->busy == 0) && 2440 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2441 if ((p->queue - p->pc) == PQ_CACHE) 2442 vm_page_deactivate(p); 2443 vm_page_busy(p); 2444 mpte = pmap_enter_quick(pmap, 2445 addr + i386_ptob(tmpidx), p, mpte); 2446 vm_page_flag_set(p, PG_MAPPED); 2447 vm_page_wakeup(p); 2448 } 2449 } 2450 } 2451 return; 2452} 2453 2454/* 2455 * pmap_prefault provides a quick way of clustering 2456 * pagefaults into a processes address space. It is a "cousin" 2457 * of pmap_object_init_pt, except it runs at page fault time instead 2458 * of mmap time. 2459 */ 2460#define PFBAK 4 2461#define PFFOR 4 2462#define PAGEORDER_SIZE (PFBAK+PFFOR) 2463 2464static int pmap_prefault_pageorder[] = { 2465 -PAGE_SIZE, PAGE_SIZE, 2466 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2467 -3 * PAGE_SIZE, 3 * PAGE_SIZE 2468 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2469}; 2470 2471void 2472pmap_prefault(pmap, addra, entry) 2473 pmap_t pmap; 2474 vm_offset_t addra; 2475 vm_map_entry_t entry; 2476{ 2477 int i; 2478 vm_offset_t starta; 2479 vm_offset_t addr; 2480 vm_pindex_t pindex; 2481 vm_page_t m, mpte; 2482 vm_object_t object; 2483 2484 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2485 return; 2486 2487 object = entry->object.vm_object; 2488 2489 starta = addra - PFBAK * PAGE_SIZE; 2490 if (starta < entry->start) { 2491 starta = entry->start; 2492 } else if (starta > addra) { 2493 starta = 0; 2494 } 2495 2496 mpte = NULL; 2497 for (i = 0; i < PAGEORDER_SIZE; i++) { 2498 vm_object_t lobject; 2499 pt_entry_t *pte; 2500 2501 addr = addra + pmap_prefault_pageorder[i]; 2502 if (addr > addra + (PFFOR * PAGE_SIZE)) 2503 addr = 0; 2504 2505 if (addr < starta || addr >= entry->end) 2506 continue; 2507 2508 if ((*pmap_pde(pmap, addr)) == NULL) 2509 continue; 2510 2511 pte = vtopte(addr); 2512 if (*pte) 2513 continue; 2514 2515 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2516 lobject = object; 2517 for (m = vm_page_lookup(lobject, pindex); 2518 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2519 lobject = lobject->backing_object) { 2520 if (lobject->backing_object_offset & PAGE_MASK) 2521 break; 2522 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2523 m = vm_page_lookup(lobject->backing_object, pindex); 2524 } 2525 2526 /* 2527 * give-up when a page is not in memory 2528 */ 2529 if (m == NULL) 2530 break; 2531 2532 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2533 (m->busy == 0) && 2534 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2535 2536 if ((m->queue - m->pc) == PQ_CACHE) { 2537 vm_page_deactivate(m); 2538 } 2539 vm_page_busy(m); 2540 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2541 vm_page_flag_set(m, PG_MAPPED); 2542 vm_page_wakeup(m); 2543 } 2544 } 2545} 2546 2547/* 2548 * Routine: pmap_change_wiring 2549 * Function: Change the wiring attribute for a map/virtual-address 2550 * pair. 2551 * In/out conditions: 2552 * The mapping must already exist in the pmap. 2553 */ 2554void 2555pmap_change_wiring(pmap, va, wired) 2556 register pmap_t pmap; 2557 vm_offset_t va; 2558 boolean_t wired; 2559{ 2560 register pt_entry_t *pte; 2561 2562 if (pmap == NULL) 2563 return; 2564 2565 pte = pmap_pte(pmap, va); 2566 2567 if (wired && !pmap_pte_w(pte)) 2568 pmap->pm_stats.wired_count++; 2569 else if (!wired && pmap_pte_w(pte)) 2570 pmap->pm_stats.wired_count--; 2571 2572 /* 2573 * Wiring is not a hardware characteristic so there is no need to 2574 * invalidate TLB. 2575 */ 2576 pmap_pte_set_w(pte, wired); 2577} 2578 2579 2580 2581/* 2582 * Copy the range specified by src_addr/len 2583 * from the source map to the range dst_addr/len 2584 * in the destination map. 2585 * 2586 * This routine is only advisory and need not do anything. 2587 */ 2588 2589void 2590pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2591 vm_offset_t src_addr) 2592{ 2593 vm_offset_t addr; 2594 vm_offset_t end_addr = src_addr + len; 2595 vm_offset_t pdnxt; 2596 pd_entry_t src_frame, dst_frame; 2597 vm_page_t m; 2598 2599 if (dst_addr != src_addr) 2600 return; 2601 2602 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2603 if (src_frame != (PTDpde & PG_FRAME)) 2604 return; 2605 2606 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2607 for (addr = src_addr; addr < end_addr; addr = pdnxt) { 2608 pt_entry_t *src_pte, *dst_pte; 2609 vm_page_t dstmpte, srcmpte; 2610 pd_entry_t srcptepaddr; 2611 unsigned ptepindex; 2612 2613 if (addr >= UPT_MIN_ADDRESS) 2614 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2615 2616 /* 2617 * Don't let optional prefaulting of pages make us go 2618 * way below the low water mark of free pages or way 2619 * above high water mark of used pv entries. 2620 */ 2621 if (cnt.v_free_count < cnt.v_free_reserved || 2622 pv_entry_count > pv_entry_high_water) 2623 break; 2624 2625 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2626 ptepindex = addr >> PDRSHIFT; 2627 2628 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2629 if (srcptepaddr == 0) 2630 continue; 2631 2632 if (srcptepaddr & PG_PS) { 2633 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2634 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2635 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2636 } 2637 continue; 2638 } 2639 2640 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2641 if ((srcmpte == NULL) || 2642 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2643 continue; 2644 2645 if (pdnxt > end_addr) 2646 pdnxt = end_addr; 2647 2648 /* 2649 * Have to recheck this before every avtopte() call below 2650 * in case we have blocked and something else used APTDpde. 2651 */ 2652 if (dst_frame != (APTDpde & PG_FRAME)) { 2653 APTDpde = dst_frame | PG_RW | PG_V; 2654 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 2655 } 2656 src_pte = vtopte(addr); 2657 dst_pte = avtopte(addr); 2658 while (addr < pdnxt) { 2659 pt_entry_t ptetemp; 2660 ptetemp = *src_pte; 2661 /* 2662 * we only virtual copy managed pages 2663 */ 2664 if ((ptetemp & PG_MANAGED) != 0) { 2665 /* 2666 * We have to check after allocpte for the 2667 * pte still being around... allocpte can 2668 * block. 2669 */ 2670 dstmpte = pmap_allocpte(dst_pmap, addr); 2671 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2672 /* 2673 * Clear the modified and 2674 * accessed (referenced) bits 2675 * during the copy. 2676 */ 2677 m = PHYS_TO_VM_PAGE(ptetemp); 2678 *dst_pte = ptetemp & ~(PG_M | PG_A); 2679 dst_pmap->pm_stats.resident_count++; 2680 pmap_insert_entry(dst_pmap, addr, 2681 dstmpte, m); 2682 } else { 2683 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2684 } 2685 if (dstmpte->hold_count >= srcmpte->hold_count) 2686 break; 2687 } 2688 addr += PAGE_SIZE; 2689 src_pte++; 2690 dst_pte++; 2691 } 2692 } 2693} 2694 2695#ifdef SMP 2696 2697/* 2698 * pmap_zpi_switchin*() 2699 * 2700 * These functions allow us to avoid doing IPIs alltogether in certain 2701 * temporary page-mapping situations (page zeroing). Instead to deal 2702 * with being preempted and moved onto a different cpu we invalidate 2703 * the page when the scheduler switches us in. This does not occur 2704 * very often so we remain relatively optimal with very little effort. 2705 */ 2706static void 2707pmap_zpi_switchin12(void) 2708{ 2709 invlpg((u_int)CADDR1); 2710 invlpg((u_int)CADDR2); 2711} 2712 2713static void 2714pmap_zpi_switchin2(void) 2715{ 2716 invlpg((u_int)CADDR2); 2717} 2718 2719static void 2720pmap_zpi_switchin3(void) 2721{ 2722 invlpg((u_int)CADDR3); 2723} 2724 2725#endif 2726 2727/* 2728 * pmap_zero_page zeros the specified hardware page by mapping 2729 * the page into KVM and using bzero to clear its contents. 2730 */ 2731void 2732pmap_zero_page(vm_page_t m) 2733{ 2734 vm_offset_t phys; 2735 2736 phys = VM_PAGE_TO_PHYS(m); 2737 if (*CMAP2) 2738 panic("pmap_zero_page: CMAP2 busy"); 2739 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2740#ifdef I386_CPU 2741 invltlb(); 2742#else 2743#ifdef SMP 2744 curthread->td_switchin = pmap_zpi_switchin2; 2745#endif 2746 invlpg((u_int)CADDR2); 2747#endif 2748#if defined(I686_CPU) 2749 if (cpu_class == CPUCLASS_686) 2750 i686_pagezero(CADDR2); 2751 else 2752#endif 2753 bzero(CADDR2, PAGE_SIZE); 2754#ifdef SMP 2755 curthread->td_switchin = NULL; 2756#endif 2757 *CMAP2 = 0; 2758} 2759 2760/* 2761 * pmap_zero_page_area zeros the specified hardware page by mapping 2762 * the page into KVM and using bzero to clear its contents. 2763 * 2764 * off and size may not cover an area beyond a single hardware page. 2765 */ 2766void 2767pmap_zero_page_area(vm_page_t m, int off, int size) 2768{ 2769 vm_offset_t phys; 2770 2771 phys = VM_PAGE_TO_PHYS(m); 2772 if (*CMAP2) 2773 panic("pmap_zero_page: CMAP2 busy"); 2774 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2775#ifdef I386_CPU 2776 invltlb(); 2777#else 2778#ifdef SMP 2779 curthread->td_switchin = pmap_zpi_switchin2; 2780#endif 2781 invlpg((u_int)CADDR2); 2782#endif 2783#if defined(I686_CPU) 2784 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2785 i686_pagezero(CADDR2); 2786 else 2787#endif 2788 bzero((char *)CADDR2 + off, size); 2789#ifdef SMP 2790 curthread->td_switchin = NULL; 2791#endif 2792 *CMAP2 = 0; 2793} 2794 2795/* 2796 * pmap_zero_page_idle zeros the specified hardware page by mapping 2797 * the page into KVM and using bzero to clear its contents. This 2798 * is intended to be called from the vm_pagezero process only and 2799 * outside of Giant. 2800 */ 2801void 2802pmap_zero_page_idle(vm_page_t m) 2803{ 2804 vm_offset_t phys; 2805 2806 phys = VM_PAGE_TO_PHYS(m); 2807 if (*CMAP3) 2808 panic("pmap_zero_page: CMAP3 busy"); 2809 *CMAP3 = PG_V | PG_RW | phys | PG_A | PG_M; 2810#ifdef I386_CPU 2811 invltlb(); 2812#else 2813#ifdef SMP 2814 curthread->td_switchin = pmap_zpi_switchin3; 2815#endif 2816 invlpg((u_int)CADDR3); 2817#endif 2818#if defined(I686_CPU) 2819 if (cpu_class == CPUCLASS_686) 2820 i686_pagezero(CADDR3); 2821 else 2822#endif 2823 bzero(CADDR3, PAGE_SIZE); 2824#ifdef SMP 2825 curthread->td_switchin = NULL; 2826#endif 2827 *CMAP3 = 0; 2828} 2829 2830/* 2831 * pmap_copy_page copies the specified (machine independent) 2832 * page by mapping the page into virtual memory and using 2833 * bcopy to copy the page, one machine dependent page at a 2834 * time. 2835 */ 2836void 2837pmap_copy_page(vm_page_t src, vm_page_t dst) 2838{ 2839 2840 if (*CMAP1) 2841 panic("pmap_copy_page: CMAP1 busy"); 2842 if (*CMAP2) 2843 panic("pmap_copy_page: CMAP2 busy"); 2844 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2845 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2846#ifdef I386_CPU 2847 invltlb(); 2848#else 2849#ifdef SMP 2850 curthread->td_switchin = pmap_zpi_switchin12; 2851#endif 2852 invlpg((u_int)CADDR1); 2853 invlpg((u_int)CADDR2); 2854#endif 2855 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2856#ifdef SMP 2857 curthread->td_switchin = NULL; 2858#endif 2859 *CMAP1 = 0; 2860 *CMAP2 = 0; 2861} 2862 2863 2864/* 2865 * Routine: pmap_pageable 2866 * Function: 2867 * Make the specified pages (by pmap, offset) 2868 * pageable (or not) as requested. 2869 * 2870 * A page which is not pageable may not take 2871 * a fault; therefore, its page table entry 2872 * must remain valid for the duration. 2873 * 2874 * This routine is merely advisory; pmap_enter 2875 * will specify that these pages are to be wired 2876 * down (or not) as appropriate. 2877 */ 2878void 2879pmap_pageable(pmap, sva, eva, pageable) 2880 pmap_t pmap; 2881 vm_offset_t sva, eva; 2882 boolean_t pageable; 2883{ 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_MAPPED | 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 return; 3071 3072 s = splvm(); 3073 3074 /* 3075 * Loop over all current mappings setting/clearing as appropos If 3076 * setting RO do we need to clear the VAC? 3077 */ 3078 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3079 /* 3080 * don't write protect pager mappings 3081 */ 3082 if (!setem && (bit == PG_RW)) { 3083 if (!pmap_track_modified(pv->pv_va)) 3084 continue; 3085 } 3086 3087#if defined(PMAP_DIAGNOSTIC) 3088 if (!pv->pv_pmap) { 3089 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3090 continue; 3091 } 3092#endif 3093 3094 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3095 3096 if (setem) { 3097 *pte |= bit; 3098 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3099 } else { 3100 pt_entry_t pbits = *pte; 3101 if (pbits & bit) { 3102 if (bit == PG_RW) { 3103 if (pbits & PG_M) { 3104 vm_page_dirty(m); 3105 } 3106 *pte = pbits & ~(PG_M|PG_RW); 3107 } else { 3108 *pte = pbits & ~bit; 3109 } 3110 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3111 } 3112 } 3113 } 3114 splx(s); 3115} 3116 3117/* 3118 * pmap_page_protect: 3119 * 3120 * Lower the permission for all mappings to a given page. 3121 */ 3122void 3123pmap_page_protect(vm_page_t m, vm_prot_t prot) 3124{ 3125 if ((prot & VM_PROT_WRITE) == 0) { 3126 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3127 pmap_changebit(m, PG_RW, FALSE); 3128 } else { 3129 pmap_remove_all(m); 3130 } 3131 } 3132} 3133 3134vm_offset_t 3135pmap_phys_address(ppn) 3136 int ppn; 3137{ 3138 return (i386_ptob(ppn)); 3139} 3140 3141/* 3142 * pmap_ts_referenced: 3143 * 3144 * Return a count of reference bits for a page, clearing those bits. 3145 * It is not necessary for every reference bit to be cleared, but it 3146 * is necessary that 0 only be returned when there are truly no 3147 * reference bits set. 3148 * 3149 * XXX: The exact number of bits to check and clear is a matter that 3150 * should be tested and standardized at some point in the future for 3151 * optimal aging of shared pages. 3152 */ 3153int 3154pmap_ts_referenced(vm_page_t m) 3155{ 3156 register pv_entry_t pv, pvf, pvn; 3157 pt_entry_t *pte; 3158 int s; 3159 int rtval = 0; 3160 3161 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3162 return (rtval); 3163 3164 s = splvm(); 3165 3166 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3167 3168 pvf = pv; 3169 3170 do { 3171 pvn = TAILQ_NEXT(pv, pv_list); 3172 3173 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3174 3175 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3176 3177 if (!pmap_track_modified(pv->pv_va)) 3178 continue; 3179 3180 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3181 3182 if (pte && (*pte & PG_A)) { 3183 *pte &= ~PG_A; 3184 3185 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3186 3187 rtval++; 3188 if (rtval > 4) { 3189 break; 3190 } 3191 } 3192 } while ((pv = pvn) != NULL && pv != pvf); 3193 } 3194 splx(s); 3195 3196 return (rtval); 3197} 3198 3199/* 3200 * pmap_is_modified: 3201 * 3202 * Return whether or not the specified physical page was modified 3203 * in any physical maps. 3204 */ 3205boolean_t 3206pmap_is_modified(vm_page_t m) 3207{ 3208 return pmap_testbit(m, PG_M); 3209} 3210 3211/* 3212 * Clear the modify bits on the specified physical page. 3213 */ 3214void 3215pmap_clear_modify(vm_page_t m) 3216{ 3217 pmap_changebit(m, PG_M, FALSE); 3218} 3219 3220/* 3221 * pmap_clear_reference: 3222 * 3223 * Clear the reference bit on the specified physical page. 3224 */ 3225void 3226pmap_clear_reference(vm_page_t m) 3227{ 3228 pmap_changebit(m, PG_A, FALSE); 3229} 3230 3231/* 3232 * Miscellaneous support routines follow 3233 */ 3234 3235static void 3236i386_protection_init() 3237{ 3238 register int *kp, prot; 3239 3240 kp = protection_codes; 3241 for (prot = 0; prot < 8; prot++) { 3242 switch (prot) { 3243 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3244 /* 3245 * Read access is also 0. There isn't any execute bit, 3246 * so just make it readable. 3247 */ 3248 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3249 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3250 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3251 *kp++ = 0; 3252 break; 3253 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3254 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3255 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3256 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3257 *kp++ = PG_RW; 3258 break; 3259 } 3260 } 3261} 3262 3263/* 3264 * Map a set of physical memory pages into the kernel virtual 3265 * address space. Return a pointer to where it is mapped. This 3266 * routine is intended to be used for mapping device memory, 3267 * NOT real memory. 3268 */ 3269void * 3270pmap_mapdev(pa, size) 3271 vm_offset_t pa; 3272 vm_size_t size; 3273{ 3274 vm_offset_t va, tmpva, offset; 3275 pt_entry_t *pte; 3276 3277 offset = pa & PAGE_MASK; 3278 size = roundup(offset + size, PAGE_SIZE); 3279 3280 GIANT_REQUIRED; 3281 3282 va = kmem_alloc_pageable(kernel_map, size); 3283 if (!va) 3284 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3285 3286 pa = pa & PG_FRAME; 3287 for (tmpva = va; size > 0; ) { 3288 pte = vtopte(tmpva); 3289 *pte = pa | PG_RW | PG_V | pgeflag; 3290 size -= PAGE_SIZE; 3291 tmpva += PAGE_SIZE; 3292 pa += PAGE_SIZE; 3293 } 3294 pmap_invalidate_range(kernel_pmap, va, tmpva); 3295 return ((void *)(va + offset)); 3296} 3297 3298void 3299pmap_unmapdev(va, size) 3300 vm_offset_t va; 3301 vm_size_t size; 3302{ 3303 vm_offset_t base, offset, tmpva; 3304 pt_entry_t *pte; 3305 3306 base = va & PG_FRAME; 3307 offset = va & PAGE_MASK; 3308 size = roundup(offset + size, PAGE_SIZE); 3309 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE) { 3310 pte = vtopte(tmpva); 3311 *pte = 0; 3312 } 3313 pmap_invalidate_range(kernel_pmap, va, tmpva); 3314 kmem_free(kernel_map, base, size); 3315} 3316 3317/* 3318 * perform the pmap work for mincore 3319 */ 3320int 3321pmap_mincore(pmap, addr) 3322 pmap_t pmap; 3323 vm_offset_t addr; 3324{ 3325 pt_entry_t *ptep, pte; 3326 vm_page_t m; 3327 int val = 0; 3328 3329 ptep = pmap_pte(pmap, addr); 3330 if (ptep == 0) { 3331 return 0; 3332 } 3333 3334 if ((pte = *ptep) != 0) { 3335 vm_offset_t pa; 3336 3337 val = MINCORE_INCORE; 3338 if ((pte & PG_MANAGED) == 0) 3339 return val; 3340 3341 pa = pte & PG_FRAME; 3342 3343 m = PHYS_TO_VM_PAGE(pa); 3344 3345 /* 3346 * Modified by us 3347 */ 3348 if (pte & PG_M) 3349 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3350 /* 3351 * Modified by someone 3352 */ 3353 else if (m->dirty || pmap_is_modified(m)) 3354 val |= MINCORE_MODIFIED_OTHER; 3355 /* 3356 * Referenced by us 3357 */ 3358 if (pte & PG_A) 3359 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3360 3361 /* 3362 * Referenced by someone 3363 */ 3364 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3365 val |= MINCORE_REFERENCED_OTHER; 3366 vm_page_flag_set(m, PG_REFERENCED); 3367 } 3368 } 3369 return val; 3370} 3371 3372void 3373pmap_activate(struct thread *td) 3374{ 3375 struct proc *p = td->td_proc; 3376 pmap_t pmap; 3377 u_int32_t cr3; 3378 3379 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3380#if defined(SMP) 3381 pmap->pm_active |= PCPU_GET(cpumask); 3382#else 3383 pmap->pm_active |= 1; 3384#endif 3385 cr3 = vtophys(pmap->pm_pdir); 3386 /* XXXKSE this is wrong. 3387 * pmap_activate is for the current thread on the current cpu 3388 */ 3389 if (p->p_flag & P_KSES) { 3390 /* Make sure all other cr3 entries are updated. */ 3391 /* what if they are running? XXXKSE (maybe abort them) */ 3392 FOREACH_THREAD_IN_PROC(p, td) { 3393 td->td_pcb->pcb_cr3 = cr3; 3394 } 3395 } else { 3396 td->td_pcb->pcb_cr3 = cr3; 3397 } 3398 load_cr3(cr3); 3399#ifdef SWTCH_OPTIM_STATS 3400 tlb_flush_count++; 3401#endif 3402} 3403 3404vm_offset_t 3405pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3406{ 3407 3408 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3409 return addr; 3410 } 3411 3412 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3413 return addr; 3414} 3415 3416 3417#if defined(PMAP_DEBUG) 3418pmap_pid_dump(int pid) 3419{ 3420 pmap_t pmap; 3421 struct proc *p; 3422 int npte = 0; 3423 int index; 3424 3425 sx_slock(&allproc_lock); 3426 LIST_FOREACH(p, &allproc, p_list) { 3427 if (p->p_pid != pid) 3428 continue; 3429 3430 if (p->p_vmspace) { 3431 int i,j; 3432 index = 0; 3433 pmap = vmspace_pmap(p->p_vmspace); 3434 for (i = 0; i < NPDEPG; i++) { 3435 pd_entry_t *pde; 3436 pt_entry_t *pte; 3437 vm_offset_t base = i << PDRSHIFT; 3438 3439 pde = &pmap->pm_pdir[i]; 3440 if (pde && pmap_pde_v(pde)) { 3441 for (j = 0; j < NPTEPG; j++) { 3442 vm_offset_t va = base + (j << PAGE_SHIFT); 3443 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3444 if (index) { 3445 index = 0; 3446 printf("\n"); 3447 } 3448 sx_sunlock(&allproc_lock); 3449 return npte; 3450 } 3451 pte = pmap_pte_quick(pmap, va); 3452 if (pte && pmap_pte_v(pte)) { 3453 pt_entry_t pa; 3454 vm_page_t m; 3455 pa = *pte; 3456 m = PHYS_TO_VM_PAGE(pa); 3457 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3458 va, pa, m->hold_count, m->wire_count, m->flags); 3459 npte++; 3460 index++; 3461 if (index >= 2) { 3462 index = 0; 3463 printf("\n"); 3464 } else { 3465 printf(" "); 3466 } 3467 } 3468 } 3469 } 3470 } 3471 } 3472 } 3473 sx_sunlock(&allproc_lock); 3474 return npte; 3475} 3476#endif 3477 3478#if defined(DEBUG) 3479 3480static void pads(pmap_t pm); 3481void pmap_pvdump(vm_offset_t pa); 3482 3483/* print address space of pmap*/ 3484static void 3485pads(pm) 3486 pmap_t pm; 3487{ 3488 int i, j; 3489 vm_offset_t va; 3490 pt_entry_t *ptep; 3491 3492 if (pm == kernel_pmap) 3493 return; 3494 for (i = 0; i < NPDEPG; i++) 3495 if (pm->pm_pdir[i]) 3496 for (j = 0; j < NPTEPG; j++) { 3497 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3498 if (pm == kernel_pmap && va < KERNBASE) 3499 continue; 3500 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3501 continue; 3502 ptep = pmap_pte_quick(pm, va); 3503 if (pmap_pte_v(ptep)) 3504 printf("%x:%x ", va, *ptep); 3505 }; 3506 3507} 3508 3509void 3510pmap_pvdump(pa) 3511 vm_offset_t pa; 3512{ 3513 pv_entry_t pv; 3514 vm_page_t m; 3515 3516 printf("pa %x", pa); 3517 m = PHYS_TO_VM_PAGE(pa); 3518 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3519 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3520 pads(pv->pv_pmap); 3521 } 3522 printf(" "); 3523} 3524#endif 3525