pmap.c revision 101197
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 101197 2002-08-02 04:14:19Z 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 m->valid = VM_PAGE_BITS_ALL; 984 } 985 pmap_qenter(ks, ma, KSTACK_PAGES); 986} 987 988/* 989 * Dispose the kernel stack for a thread that has exited. 990 * This routine directly impacts the exit perf of a process and thread. 991 */ 992void 993pmap_dispose_thread(td) 994 struct thread *td; 995{ 996 int i; 997 vm_object_t ksobj; 998 vm_offset_t ks; 999 vm_page_t m; 1000 1001 ksobj = td->td_kstack_obj; 1002 ks = td->td_kstack; 1003 pmap_qremove(ks, KSTACK_PAGES); 1004 for (i = 0; i < KSTACK_PAGES; i++) { 1005 m = vm_page_lookup(ksobj, i); 1006 if (m == NULL) 1007 panic("pmap_dispose_thread: kstack already missing?"); 1008 vm_page_lock_queues(); 1009 vm_page_busy(m); 1010 vm_page_unwire(m, 0); 1011 vm_page_free(m); 1012 vm_page_unlock_queues(); 1013 } 1014 /* 1015 * Free the space that this stack was mapped to in the kernel 1016 * address map. 1017 */ 1018#ifdef KSTACK_GUARD 1019 kmem_free(kernel_map, ks - PAGE_SIZE, (KSTACK_PAGES + 1) * PAGE_SIZE); 1020#else 1021 kmem_free(kernel_map, ks, KSTACK_PAGES * PAGE_SIZE); 1022#endif 1023 vm_object_deallocate(ksobj); 1024} 1025 1026/* 1027 * Allow the Kernel stack for a thread to be prejudicially paged out. 1028 */ 1029void 1030pmap_swapout_thread(td) 1031 struct thread *td; 1032{ 1033 int i; 1034 vm_object_t ksobj; 1035 vm_offset_t ks; 1036 vm_page_t m; 1037 1038 ksobj = td->td_kstack_obj; 1039 ks = td->td_kstack; 1040 pmap_qremove(ks, KSTACK_PAGES); 1041 for (i = 0; i < KSTACK_PAGES; i++) { 1042 m = vm_page_lookup(ksobj, i); 1043 if (m == NULL) 1044 panic("pmap_swapout_thread: kstack already missing?"); 1045 vm_page_lock_queues(); 1046 vm_page_dirty(m); 1047 vm_page_unwire(m, 0); 1048 vm_page_unlock_queues(); 1049 } 1050} 1051 1052/* 1053 * Bring the kernel stack for a specified thread back in. 1054 */ 1055void 1056pmap_swapin_thread(td) 1057 struct thread *td; 1058{ 1059 int i, rv; 1060 vm_page_t ma[KSTACK_PAGES]; 1061 vm_object_t ksobj; 1062 vm_offset_t ks; 1063 vm_page_t m; 1064 1065 ksobj = td->td_kstack_obj; 1066 ks = td->td_kstack; 1067 for (i = 0; i < KSTACK_PAGES; i++) { 1068 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1069 if (m->valid != VM_PAGE_BITS_ALL) { 1070 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1071 if (rv != VM_PAGER_OK) 1072 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1073 m = vm_page_lookup(ksobj, i); 1074 m->valid = VM_PAGE_BITS_ALL; 1075 } 1076 ma[i] = m; 1077 vm_page_lock_queues(); 1078 vm_page_wire(m); 1079 vm_page_wakeup(m); 1080 vm_page_unlock_queues(); 1081 } 1082 pmap_qenter(ks, ma, KSTACK_PAGES); 1083} 1084 1085/*************************************************** 1086 * Page table page management routines..... 1087 ***************************************************/ 1088 1089/* 1090 * This routine unholds page table pages, and if the hold count 1091 * drops to zero, then it decrements the wire count. 1092 */ 1093static int 1094_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1095{ 1096 1097 while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) 1098 ; 1099 1100 if (m->hold_count == 0) { 1101 vm_offset_t pteva; 1102 /* 1103 * unmap the page table page 1104 */ 1105 pmap->pm_pdir[m->pindex] = 0; 1106 --pmap->pm_stats.resident_count; 1107 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1108 (PTDpde & PG_FRAME)) { 1109 /* 1110 * Do a invltlb to make the invalidated mapping 1111 * take effect immediately. 1112 */ 1113 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); 1114 pmap_invalidate_page(pmap, pteva); 1115 } 1116 1117 if (pmap->pm_ptphint == m) 1118 pmap->pm_ptphint = NULL; 1119 1120 /* 1121 * If the page is finally unwired, simply free it. 1122 */ 1123 --m->wire_count; 1124 if (m->wire_count == 0) { 1125 1126 vm_page_flash(m); 1127 vm_page_busy(m); 1128 vm_page_free_zero(m); 1129 --cnt.v_wire_count; 1130 } 1131 return 1; 1132 } 1133 return 0; 1134} 1135 1136static PMAP_INLINE int 1137pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1138{ 1139 vm_page_unhold(m); 1140 if (m->hold_count == 0) 1141 return _pmap_unwire_pte_hold(pmap, m); 1142 else 1143 return 0; 1144} 1145 1146/* 1147 * After removing a page table entry, this routine is used to 1148 * conditionally free the page, and manage the hold/wire counts. 1149 */ 1150static int 1151pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1152{ 1153 unsigned ptepindex; 1154 if (va >= VM_MAXUSER_ADDRESS) 1155 return 0; 1156 1157 if (mpte == NULL) { 1158 ptepindex = (va >> PDRSHIFT); 1159 if (pmap->pm_ptphint && 1160 (pmap->pm_ptphint->pindex == ptepindex)) { 1161 mpte = pmap->pm_ptphint; 1162 } else { 1163 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1164 pmap->pm_ptphint = mpte; 1165 } 1166 } 1167 1168 return pmap_unwire_pte_hold(pmap, mpte); 1169} 1170 1171void 1172pmap_pinit0(pmap) 1173 struct pmap *pmap; 1174{ 1175 pmap->pm_pdir = 1176 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1177 pmap_kenter((vm_offset_t)pmap->pm_pdir, (vm_offset_t)IdlePTD); 1178#ifndef I386_CPU 1179 invlpg((vm_offset_t)pmap->pm_pdir); 1180#else 1181 invltlb(); 1182#endif 1183 pmap->pm_ptphint = NULL; 1184 pmap->pm_active = 0; 1185 TAILQ_INIT(&pmap->pm_pvlist); 1186 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1187 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1188} 1189 1190/* 1191 * Initialize a preallocated and zeroed pmap structure, 1192 * such as one in a vmspace structure. 1193 */ 1194void 1195pmap_pinit(pmap) 1196 register struct pmap *pmap; 1197{ 1198 vm_page_t ptdpg; 1199 1200 /* 1201 * No need to allocate page table space yet but we do need a valid 1202 * page directory table. 1203 */ 1204 if (pmap->pm_pdir == NULL) 1205 pmap->pm_pdir = 1206 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1207 1208 /* 1209 * allocate object for the ptes 1210 */ 1211 if (pmap->pm_pteobj == NULL) 1212 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1213 1214 /* 1215 * allocate the page directory page 1216 */ 1217 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1218 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED); 1219 vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/ 1220 ptdpg->valid = VM_PAGE_BITS_ALL; 1221 1222 pmap_qenter((vm_offset_t) pmap->pm_pdir, &ptdpg, 1); 1223 if ((ptdpg->flags & PG_ZERO) == 0) 1224 bzero(pmap->pm_pdir, PAGE_SIZE); 1225 1226 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1227 /* Wire in kernel global address entries. */ 1228 /* XXX copies current process, does not fill in MPPTDI */ 1229 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1230#ifdef SMP 1231 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1232#endif 1233 1234 /* install self-referential address mapping entry */ 1235 pmap->pm_pdir[PTDPTDI] = 1236 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1237 1238 pmap->pm_active = 0; 1239 pmap->pm_ptphint = NULL; 1240 TAILQ_INIT(&pmap->pm_pvlist); 1241 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1242} 1243 1244/* 1245 * Wire in kernel global address entries. To avoid a race condition 1246 * between pmap initialization and pmap_growkernel, this procedure 1247 * should be called after the vmspace is attached to the process 1248 * but before this pmap is activated. 1249 */ 1250void 1251pmap_pinit2(pmap) 1252 struct pmap *pmap; 1253{ 1254 /* XXX: Remove this stub when no longer called */ 1255} 1256 1257static int 1258pmap_release_free_page(pmap_t pmap, vm_page_t p) 1259{ 1260 pd_entry_t *pde = pmap->pm_pdir; 1261 /* 1262 * This code optimizes the case of freeing non-busy 1263 * page-table pages. Those pages are zero now, and 1264 * might as well be placed directly into the zero queue. 1265 */ 1266 if (vm_page_sleep_busy(p, FALSE, "pmaprl")) 1267 return 0; 1268 1269 vm_page_lock_queues(); 1270 vm_page_busy(p); 1271 1272 /* 1273 * Remove the page table page from the processes address space. 1274 */ 1275 pde[p->pindex] = 0; 1276 pmap->pm_stats.resident_count--; 1277 1278 if (p->hold_count) { 1279 panic("pmap_release: freeing held page table page"); 1280 } 1281 /* 1282 * Page directory pages need to have the kernel 1283 * stuff cleared, so they can go into the zero queue also. 1284 */ 1285 if (p->pindex == PTDPTDI) { 1286 bzero(pde + KPTDI, nkpt * PTESIZE); 1287#ifdef SMP 1288 pde[MPPTDI] = 0; 1289#endif 1290 pde[APTDPTDI] = 0; 1291 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1292 } 1293 1294 if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex)) 1295 pmap->pm_ptphint = NULL; 1296 1297 p->wire_count--; 1298 cnt.v_wire_count--; 1299 vm_page_free_zero(p); 1300 vm_page_unlock_queues(); 1301 return 1; 1302} 1303 1304/* 1305 * this routine is called if the page table page is not 1306 * mapped correctly. 1307 */ 1308static vm_page_t 1309_pmap_allocpte(pmap, ptepindex) 1310 pmap_t pmap; 1311 unsigned ptepindex; 1312{ 1313 vm_offset_t pteva, ptepa; /* XXXPA */ 1314 vm_page_t m; 1315 1316 /* 1317 * Find or fabricate a new pagetable page 1318 */ 1319 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1320 VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1321 1322 KASSERT(m->queue == PQ_NONE, 1323 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1324 1325 if (m->wire_count == 0) 1326 cnt.v_wire_count++; 1327 m->wire_count++; 1328 1329 /* 1330 * Increment the hold count for the page table page 1331 * (denoting a new mapping.) 1332 */ 1333 m->hold_count++; 1334 1335 /* 1336 * Map the pagetable page into the process address space, if 1337 * it isn't already there. 1338 */ 1339 1340 pmap->pm_stats.resident_count++; 1341 1342 ptepa = VM_PAGE_TO_PHYS(m); 1343 pmap->pm_pdir[ptepindex] = 1344 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1345 1346 /* 1347 * Set the page table hint 1348 */ 1349 pmap->pm_ptphint = m; 1350 1351 /* 1352 * Try to use the new mapping, but if we cannot, then 1353 * do it with the routine that maps the page explicitly. 1354 */ 1355 if ((m->flags & PG_ZERO) == 0) { 1356 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1357 (PTDpde & PG_FRAME)) { 1358 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1359 bzero((caddr_t) pteva, PAGE_SIZE); 1360 } else { 1361 pmap_zero_page(m); 1362 } 1363 } 1364 1365 m->valid = VM_PAGE_BITS_ALL; 1366 vm_page_flag_clear(m, PG_ZERO); 1367 vm_page_flag_set(m, PG_MAPPED); 1368 vm_page_wakeup(m); 1369 1370 return m; 1371} 1372 1373static vm_page_t 1374pmap_allocpte(pmap_t pmap, vm_offset_t va) 1375{ 1376 unsigned ptepindex; 1377 pd_entry_t ptepa; 1378 vm_page_t m; 1379 1380 /* 1381 * Calculate pagetable page index 1382 */ 1383 ptepindex = va >> PDRSHIFT; 1384 1385 /* 1386 * Get the page directory entry 1387 */ 1388 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1389 1390 /* 1391 * This supports switching from a 4MB page to a 1392 * normal 4K page. 1393 */ 1394 if (ptepa & PG_PS) { 1395 pmap->pm_pdir[ptepindex] = 0; 1396 ptepa = 0; 1397 pmap_invalidate_all(kernel_pmap); 1398 } 1399 1400 /* 1401 * If the page table page is mapped, we just increment the 1402 * hold count, and activate it. 1403 */ 1404 if (ptepa) { 1405 /* 1406 * In order to get the page table page, try the 1407 * hint first. 1408 */ 1409 if (pmap->pm_ptphint && 1410 (pmap->pm_ptphint->pindex == ptepindex)) { 1411 m = pmap->pm_ptphint; 1412 } else { 1413 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1414 pmap->pm_ptphint = m; 1415 } 1416 m->hold_count++; 1417 return m; 1418 } 1419 /* 1420 * Here if the pte page isn't mapped, or if it has been deallocated. 1421 */ 1422 return _pmap_allocpte(pmap, ptepindex); 1423} 1424 1425 1426/*************************************************** 1427* Pmap allocation/deallocation routines. 1428 ***************************************************/ 1429 1430/* 1431 * Release any resources held by the given physical map. 1432 * Called when a pmap initialized by pmap_pinit is being released. 1433 * Should only be called if the map contains no valid mappings. 1434 */ 1435void 1436pmap_release(pmap_t pmap) 1437{ 1438 vm_page_t p,n,ptdpg; 1439 vm_object_t object = pmap->pm_pteobj; 1440 int curgeneration; 1441 1442#if defined(DIAGNOSTIC) 1443 if (object->ref_count != 1) 1444 panic("pmap_release: pteobj reference count != 1"); 1445#endif 1446 1447 ptdpg = NULL; 1448 LIST_REMOVE(pmap, pm_list); 1449retry: 1450 curgeneration = object->generation; 1451 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1452 n = TAILQ_NEXT(p, listq); 1453 if (p->pindex == PTDPTDI) { 1454 ptdpg = p; 1455 continue; 1456 } 1457 while (1) { 1458 if (!pmap_release_free_page(pmap, p) && 1459 (object->generation != curgeneration)) 1460 goto retry; 1461 } 1462 } 1463 1464 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1465 goto retry; 1466} 1467 1468static int 1469kvm_size(SYSCTL_HANDLER_ARGS) 1470{ 1471 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1472 1473 return sysctl_handle_long(oidp, &ksize, 0, req); 1474} 1475SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1476 0, 0, kvm_size, "IU", "Size of KVM"); 1477 1478static int 1479kvm_free(SYSCTL_HANDLER_ARGS) 1480{ 1481 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1482 1483 return sysctl_handle_long(oidp, &kfree, 0, req); 1484} 1485SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1486 0, 0, kvm_free, "IU", "Amount of KVM free"); 1487 1488/* 1489 * grow the number of kernel page table entries, if needed 1490 */ 1491void 1492pmap_growkernel(vm_offset_t addr) 1493{ 1494 struct pmap *pmap; 1495 int s; 1496 vm_offset_t ptppaddr; 1497 vm_page_t nkpg; 1498 pd_entry_t newpdir; 1499 1500 s = splhigh(); 1501 if (kernel_vm_end == 0) { 1502 kernel_vm_end = KERNBASE; 1503 nkpt = 0; 1504 while (pdir_pde(PTD, kernel_vm_end)) { 1505 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1506 nkpt++; 1507 } 1508 } 1509 addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1510 while (kernel_vm_end < addr) { 1511 if (pdir_pde(PTD, kernel_vm_end)) { 1512 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1513 continue; 1514 } 1515 1516 /* 1517 * This index is bogus, but out of the way 1518 */ 1519 nkpg = vm_page_alloc(kptobj, nkpt, 1520 VM_ALLOC_SYSTEM | VM_ALLOC_WIRED); 1521 if (!nkpg) 1522 panic("pmap_growkernel: no memory to grow kernel"); 1523 1524 nkpt++; 1525 1526 pmap_zero_page(nkpg); 1527 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1528 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1529 pdir_pde(PTD, kernel_vm_end) = newpdir; 1530 1531 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1532 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1533 } 1534 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1535 } 1536 splx(s); 1537} 1538 1539 1540/*************************************************** 1541 * page management routines. 1542 ***************************************************/ 1543 1544/* 1545 * free the pv_entry back to the free list 1546 */ 1547static PMAP_INLINE void 1548free_pv_entry(pv_entry_t pv) 1549{ 1550 pv_entry_count--; 1551 uma_zfree(pvzone, pv); 1552} 1553 1554/* 1555 * get a new pv_entry, allocating a block from the system 1556 * when needed. 1557 * the memory allocation is performed bypassing the malloc code 1558 * because of the possibility of allocations at interrupt time. 1559 */ 1560static pv_entry_t 1561get_pv_entry(void) 1562{ 1563 pv_entry_count++; 1564 if (pv_entry_high_water && 1565 (pv_entry_count > pv_entry_high_water) && 1566 (pmap_pagedaemon_waken == 0)) { 1567 pmap_pagedaemon_waken = 1; 1568 wakeup (&vm_pages_needed); 1569 } 1570 return uma_zalloc(pvzone, M_NOWAIT); 1571} 1572 1573/* 1574 * This routine is very drastic, but can save the system 1575 * in a pinch. 1576 */ 1577void 1578pmap_collect() 1579{ 1580 int i; 1581 vm_page_t m; 1582 static int warningdone = 0; 1583 1584 if (pmap_pagedaemon_waken == 0) 1585 return; 1586 1587 if (warningdone < 5) { 1588 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1589 warningdone++; 1590 } 1591 1592 for(i = 0; i < vm_page_array_size; i++) { 1593 m = &vm_page_array[i]; 1594 if (m->wire_count || m->hold_count || m->busy || 1595 (m->flags & (PG_BUSY | PG_UNMANAGED))) 1596 continue; 1597 pmap_remove_all(m); 1598 } 1599 pmap_pagedaemon_waken = 0; 1600} 1601 1602 1603/* 1604 * If it is the first entry on the list, it is actually 1605 * in the header and we must copy the following entry up 1606 * to the header. Otherwise we must search the list for 1607 * the entry. In either case we free the now unused entry. 1608 */ 1609 1610static int 1611pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1612{ 1613 pv_entry_t pv; 1614 int rtval; 1615 int s; 1616 1617 s = splvm(); 1618 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1619 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1620 if (pmap == pv->pv_pmap && va == pv->pv_va) 1621 break; 1622 } 1623 } else { 1624 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1625 if (va == pv->pv_va) 1626 break; 1627 } 1628 } 1629 1630 rtval = 0; 1631 if (pv) { 1632 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1633 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1634 m->md.pv_list_count--; 1635 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1636 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1637 1638 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1639 free_pv_entry(pv); 1640 } 1641 1642 splx(s); 1643 return rtval; 1644} 1645 1646/* 1647 * Create a pv entry for page at pa for 1648 * (pmap, va). 1649 */ 1650static void 1651pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1652{ 1653 1654 int s; 1655 pv_entry_t pv; 1656 1657 s = splvm(); 1658 pv = get_pv_entry(); 1659 pv->pv_va = va; 1660 pv->pv_pmap = pmap; 1661 pv->pv_ptem = mpte; 1662 1663 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1664 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1665 m->md.pv_list_count++; 1666 1667 splx(s); 1668} 1669 1670/* 1671 * pmap_remove_pte: do the things to unmap a page in a process 1672 */ 1673static int 1674pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1675{ 1676 pt_entry_t oldpte; 1677 vm_page_t m; 1678 1679 oldpte = atomic_readandclear_int(ptq); 1680 if (oldpte & PG_W) 1681 pmap->pm_stats.wired_count -= 1; 1682 /* 1683 * Machines that don't support invlpg, also don't support 1684 * PG_G. 1685 */ 1686 if (oldpte & PG_G) 1687 pmap_invalidate_page(kernel_pmap, va); 1688 pmap->pm_stats.resident_count -= 1; 1689 if (oldpte & PG_MANAGED) { 1690 m = PHYS_TO_VM_PAGE(oldpte); 1691 if (oldpte & PG_M) { 1692#if defined(PMAP_DIAGNOSTIC) 1693 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1694 printf( 1695 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1696 va, oldpte); 1697 } 1698#endif 1699 if (pmap_track_modified(va)) 1700 vm_page_dirty(m); 1701 } 1702 if (oldpte & PG_A) 1703 vm_page_flag_set(m, PG_REFERENCED); 1704 return pmap_remove_entry(pmap, m, va); 1705 } else { 1706 return pmap_unuse_pt(pmap, va, NULL); 1707 } 1708 1709 return 0; 1710} 1711 1712/* 1713 * Remove a single page from a process address space 1714 */ 1715static void 1716pmap_remove_page(pmap_t pmap, vm_offset_t va) 1717{ 1718 register pt_entry_t *ptq; 1719 1720 /* 1721 * if there is no pte for this address, just skip it!!! 1722 */ 1723 if (*pmap_pde(pmap, va) == 0) { 1724 return; 1725 } 1726 1727 /* 1728 * get a local va for mappings for this pmap. 1729 */ 1730 ptq = get_ptbase(pmap) + i386_btop(va); 1731 if (*ptq) { 1732 (void) pmap_remove_pte(pmap, ptq, va); 1733 pmap_invalidate_page(pmap, va); 1734 } 1735 return; 1736} 1737 1738/* 1739 * Remove the given range of addresses from the specified map. 1740 * 1741 * It is assumed that the start and end are properly 1742 * rounded to the page size. 1743 */ 1744void 1745pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1746{ 1747 register pt_entry_t *ptbase; 1748 vm_offset_t pdnxt; 1749 pd_entry_t ptpaddr; 1750 vm_offset_t sindex, eindex; 1751 int anyvalid; 1752 1753 if (pmap == NULL) 1754 return; 1755 1756 if (pmap->pm_stats.resident_count == 0) 1757 return; 1758 1759 /* 1760 * special handling of removing one page. a very 1761 * common operation and easy to short circuit some 1762 * code. 1763 */ 1764 if ((sva + PAGE_SIZE == eva) && 1765 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1766 pmap_remove_page(pmap, sva); 1767 return; 1768 } 1769 1770 anyvalid = 0; 1771 1772 /* 1773 * Get a local virtual address for the mappings that are being 1774 * worked with. 1775 */ 1776 ptbase = get_ptbase(pmap); 1777 1778 sindex = i386_btop(sva); 1779 eindex = i386_btop(eva); 1780 1781 for (; sindex < eindex; sindex = pdnxt) { 1782 unsigned pdirindex; 1783 1784 /* 1785 * Calculate index for next page table. 1786 */ 1787 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1788 if (pmap->pm_stats.resident_count == 0) 1789 break; 1790 1791 pdirindex = sindex / NPDEPG; 1792 ptpaddr = pmap->pm_pdir[pdirindex]; 1793 if ((ptpaddr & PG_PS) != 0) { 1794 pmap->pm_pdir[pdirindex] = 0; 1795 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1796 anyvalid++; 1797 continue; 1798 } 1799 1800 /* 1801 * Weed out invalid mappings. Note: we assume that the page 1802 * directory table is always allocated, and in kernel virtual. 1803 */ 1804 if (ptpaddr == 0) 1805 continue; 1806 1807 /* 1808 * Limit our scan to either the end of the va represented 1809 * by the current page table page, or to the end of the 1810 * range being removed. 1811 */ 1812 if (pdnxt > eindex) { 1813 pdnxt = eindex; 1814 } 1815 1816 for (; sindex != pdnxt; sindex++) { 1817 vm_offset_t va; 1818 if (ptbase[sindex] == 0) { 1819 continue; 1820 } 1821 va = i386_ptob(sindex); 1822 1823 anyvalid++; 1824 if (pmap_remove_pte(pmap, 1825 ptbase + sindex, va)) 1826 break; 1827 } 1828 } 1829 1830 if (anyvalid) 1831 pmap_invalidate_all(pmap); 1832} 1833 1834/* 1835 * Routine: pmap_remove_all 1836 * Function: 1837 * Removes this physical page from 1838 * all physical maps in which it resides. 1839 * Reflects back modify bits to the pager. 1840 * 1841 * Notes: 1842 * Original versions of this routine were very 1843 * inefficient because they iteratively called 1844 * pmap_remove (slow...) 1845 */ 1846 1847static void 1848pmap_remove_all(vm_page_t m) 1849{ 1850 register pv_entry_t pv; 1851 pt_entry_t *pte, tpte; 1852 int s; 1853 1854#if defined(PMAP_DIAGNOSTIC) 1855 /* 1856 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1857 * pages! 1858 */ 1859 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1860 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1861 } 1862#endif 1863 1864 s = splvm(); 1865 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1866 pv->pv_pmap->pm_stats.resident_count--; 1867 1868 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1869 1870 tpte = atomic_readandclear_int(pte); 1871 if (tpte & PG_W) 1872 pv->pv_pmap->pm_stats.wired_count--; 1873 1874 if (tpte & PG_A) 1875 vm_page_flag_set(m, PG_REFERENCED); 1876 1877 /* 1878 * Update the vm_page_t clean and reference bits. 1879 */ 1880 if (tpte & PG_M) { 1881#if defined(PMAP_DIAGNOSTIC) 1882 if (pmap_nw_modified((pt_entry_t) tpte)) { 1883 printf( 1884 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1885 pv->pv_va, tpte); 1886 } 1887#endif 1888 if (pmap_track_modified(pv->pv_va)) 1889 vm_page_dirty(m); 1890 } 1891 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1892 1893 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1894 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1895 m->md.pv_list_count--; 1896 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1897 free_pv_entry(pv); 1898 } 1899 1900 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1901 1902 splx(s); 1903} 1904 1905/* 1906 * Set the physical protection on the 1907 * specified range of this map as requested. 1908 */ 1909void 1910pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1911{ 1912 register pt_entry_t *ptbase; 1913 vm_offset_t pdnxt; 1914 pd_entry_t ptpaddr; 1915 vm_offset_t sindex, eindex; 1916 int anychanged; 1917 1918 if (pmap == NULL) 1919 return; 1920 1921 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1922 pmap_remove(pmap, sva, eva); 1923 return; 1924 } 1925 1926 if (prot & VM_PROT_WRITE) 1927 return; 1928 1929 anychanged = 0; 1930 1931 ptbase = get_ptbase(pmap); 1932 1933 sindex = i386_btop(sva); 1934 eindex = i386_btop(eva); 1935 1936 for (; sindex < eindex; sindex = pdnxt) { 1937 1938 unsigned pdirindex; 1939 1940 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1941 1942 pdirindex = sindex / NPDEPG; 1943 ptpaddr = pmap->pm_pdir[pdirindex]; 1944 if ((ptpaddr & PG_PS) != 0) { 1945 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1946 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1947 anychanged++; 1948 continue; 1949 } 1950 1951 /* 1952 * Weed out invalid mappings. Note: we assume that the page 1953 * directory table is always allocated, and in kernel virtual. 1954 */ 1955 if (ptpaddr == 0) 1956 continue; 1957 1958 if (pdnxt > eindex) { 1959 pdnxt = eindex; 1960 } 1961 1962 for (; sindex != pdnxt; sindex++) { 1963 1964 pt_entry_t pbits; 1965 vm_page_t m; 1966 1967 pbits = ptbase[sindex]; 1968 1969 if (pbits & PG_MANAGED) { 1970 m = NULL; 1971 if (pbits & PG_A) { 1972 m = PHYS_TO_VM_PAGE(pbits); 1973 vm_page_flag_set(m, PG_REFERENCED); 1974 pbits &= ~PG_A; 1975 } 1976 if (pbits & PG_M) { 1977 if (pmap_track_modified(i386_ptob(sindex))) { 1978 if (m == NULL) 1979 m = PHYS_TO_VM_PAGE(pbits); 1980 vm_page_dirty(m); 1981 pbits &= ~PG_M; 1982 } 1983 } 1984 } 1985 1986 pbits &= ~PG_RW; 1987 1988 if (pbits != ptbase[sindex]) { 1989 ptbase[sindex] = pbits; 1990 anychanged = 1; 1991 } 1992 } 1993 } 1994 if (anychanged) 1995 pmap_invalidate_all(pmap); 1996} 1997 1998/* 1999 * Insert the given physical page (p) at 2000 * the specified virtual address (v) in the 2001 * target physical map with the protection requested. 2002 * 2003 * If specified, the page will be wired down, meaning 2004 * that the related pte can not be reclaimed. 2005 * 2006 * NB: This is the only routine which MAY NOT lazy-evaluate 2007 * or lose information. That is, this routine must actually 2008 * insert this page into the given map NOW. 2009 */ 2010void 2011pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2012 boolean_t wired) 2013{ 2014 vm_offset_t pa; 2015 register pt_entry_t *pte; 2016 vm_offset_t opa; 2017 pt_entry_t origpte, newpte; 2018 vm_page_t mpte; 2019 2020 if (pmap == NULL) 2021 return; 2022 2023 va &= PG_FRAME; 2024#ifdef PMAP_DIAGNOSTIC 2025 if (va > VM_MAX_KERNEL_ADDRESS) 2026 panic("pmap_enter: toobig"); 2027 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2028 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2029#endif 2030 2031 mpte = NULL; 2032 /* 2033 * In the case that a page table page is not 2034 * resident, we are creating it here. 2035 */ 2036 if (va < VM_MAXUSER_ADDRESS) { 2037 mpte = pmap_allocpte(pmap, va); 2038 } 2039#if 0 && defined(PMAP_DIAGNOSTIC) 2040 else { 2041 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2042 origpte = *pdeaddr; 2043 if ((origpte & PG_V) == 0) { 2044 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2045 pmap->pm_pdir[PTDPTDI], origpte, va); 2046 } 2047 } 2048#endif 2049 2050 pte = pmap_pte(pmap, va); 2051 2052 /* 2053 * Page Directory table entry not valid, we need a new PT page 2054 */ 2055 if (pte == NULL) { 2056 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2057 (void *)pmap->pm_pdir[PTDPTDI], va); 2058 } 2059 2060 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2061 origpte = *(vm_offset_t *)pte; 2062 opa = origpte & PG_FRAME; 2063 2064 if (origpte & PG_PS) 2065 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2066 2067 /* 2068 * Mapping has not changed, must be protection or wiring change. 2069 */ 2070 if (origpte && (opa == pa)) { 2071 /* 2072 * Wiring change, just update stats. We don't worry about 2073 * wiring PT pages as they remain resident as long as there 2074 * are valid mappings in them. Hence, if a user page is wired, 2075 * the PT page will be also. 2076 */ 2077 if (wired && ((origpte & PG_W) == 0)) 2078 pmap->pm_stats.wired_count++; 2079 else if (!wired && (origpte & PG_W)) 2080 pmap->pm_stats.wired_count--; 2081 2082#if defined(PMAP_DIAGNOSTIC) 2083 if (pmap_nw_modified((pt_entry_t) origpte)) { 2084 printf( 2085 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2086 va, origpte); 2087 } 2088#endif 2089 2090 /* 2091 * Remove extra pte reference 2092 */ 2093 if (mpte) 2094 mpte->hold_count--; 2095 2096 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2097 if ((origpte & PG_RW) == 0) { 2098 *pte |= PG_RW; 2099 pmap_invalidate_page(pmap, va); 2100 } 2101 return; 2102 } 2103 2104 /* 2105 * We might be turning off write access to the page, 2106 * so we go ahead and sense modify status. 2107 */ 2108 if (origpte & PG_MANAGED) { 2109 if ((origpte & PG_M) && pmap_track_modified(va)) { 2110 vm_page_t om; 2111 om = PHYS_TO_VM_PAGE(opa); 2112 vm_page_dirty(om); 2113 } 2114 pa |= PG_MANAGED; 2115 } 2116 goto validate; 2117 } 2118 /* 2119 * Mapping has changed, invalidate old range and fall through to 2120 * handle validating new mapping. 2121 */ 2122 if (opa) { 2123 int err; 2124 err = pmap_remove_pte(pmap, pte, va); 2125 if (err) 2126 panic("pmap_enter: pte vanished, va: 0x%x", va); 2127 } 2128 2129 /* 2130 * Enter on the PV list if part of our managed memory. Note that we 2131 * raise IPL while manipulating pv_table since pmap_enter can be 2132 * called at interrupt time. 2133 */ 2134 if (pmap_initialized && 2135 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2136 pmap_insert_entry(pmap, va, mpte, m); 2137 pa |= PG_MANAGED; 2138 } 2139 2140 /* 2141 * Increment counters 2142 */ 2143 pmap->pm_stats.resident_count++; 2144 if (wired) 2145 pmap->pm_stats.wired_count++; 2146 2147validate: 2148 /* 2149 * Now validate mapping with desired protection/wiring. 2150 */ 2151 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2152 2153 if (wired) 2154 newpte |= PG_W; 2155 if (va < VM_MAXUSER_ADDRESS) 2156 newpte |= PG_U; 2157 if (pmap == kernel_pmap) 2158 newpte |= pgeflag; 2159 2160 /* 2161 * if the mapping or permission bits are different, we need 2162 * to update the pte. 2163 */ 2164 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2165 *pte = newpte | PG_A; 2166 /*if (origpte)*/ { 2167 pmap_invalidate_page(pmap, va); 2168 } 2169 } 2170} 2171 2172/* 2173 * this code makes some *MAJOR* assumptions: 2174 * 1. Current pmap & pmap exists. 2175 * 2. Not wired. 2176 * 3. Read access. 2177 * 4. No page table pages. 2178 * 5. Tlbflush is deferred to calling procedure. 2179 * 6. Page IS managed. 2180 * but is *MUCH* faster than pmap_enter... 2181 */ 2182 2183static vm_page_t 2184pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2185{ 2186 pt_entry_t *pte; 2187 vm_offset_t pa; 2188 2189 /* 2190 * In the case that a page table page is not 2191 * resident, we are creating it here. 2192 */ 2193 if (va < VM_MAXUSER_ADDRESS) { 2194 unsigned ptepindex; 2195 pd_entry_t ptepa; 2196 2197 /* 2198 * Calculate pagetable page index 2199 */ 2200 ptepindex = va >> PDRSHIFT; 2201 if (mpte && (mpte->pindex == ptepindex)) { 2202 mpte->hold_count++; 2203 } else { 2204retry: 2205 /* 2206 * Get the page directory entry 2207 */ 2208 ptepa = pmap->pm_pdir[ptepindex]; 2209 2210 /* 2211 * If the page table page is mapped, we just increment 2212 * the hold count, and activate it. 2213 */ 2214 if (ptepa) { 2215 if (ptepa & PG_PS) 2216 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2217 if (pmap->pm_ptphint && 2218 (pmap->pm_ptphint->pindex == ptepindex)) { 2219 mpte = pmap->pm_ptphint; 2220 } else { 2221 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2222 pmap->pm_ptphint = mpte; 2223 } 2224 if (mpte == NULL) 2225 goto retry; 2226 mpte->hold_count++; 2227 } else { 2228 mpte = _pmap_allocpte(pmap, ptepindex); 2229 } 2230 } 2231 } else { 2232 mpte = NULL; 2233 } 2234 2235 /* 2236 * This call to vtopte makes the assumption that we are 2237 * entering the page into the current pmap. In order to support 2238 * quick entry into any pmap, one would likely use pmap_pte_quick. 2239 * But that isn't as quick as vtopte. 2240 */ 2241 pte = vtopte(va); 2242 if (*pte) { 2243 if (mpte) 2244 pmap_unwire_pte_hold(pmap, mpte); 2245 return 0; 2246 } 2247 2248 /* 2249 * Enter on the PV list if part of our managed memory. Note that we 2250 * raise IPL while manipulating pv_table since pmap_enter can be 2251 * called at interrupt time. 2252 */ 2253 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2254 pmap_insert_entry(pmap, va, mpte, m); 2255 2256 /* 2257 * Increment counters 2258 */ 2259 pmap->pm_stats.resident_count++; 2260 2261 pa = VM_PAGE_TO_PHYS(m); 2262 2263 /* 2264 * Now validate mapping with RO protection 2265 */ 2266 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2267 *pte = pa | PG_V | PG_U; 2268 else 2269 *pte = pa | PG_V | PG_U | PG_MANAGED; 2270 2271 return mpte; 2272} 2273 2274/* 2275 * Make a temporary mapping for a physical address. This is only intended 2276 * to be used for panic dumps. 2277 */ 2278void * 2279pmap_kenter_temporary(vm_offset_t pa, int i) 2280{ 2281 vm_offset_t va; 2282 2283 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE); 2284 pmap_kenter(va, pa); 2285#ifndef I386_CPU 2286 invlpg(va); 2287#else 2288 invltlb(); 2289#endif 2290 return ((void *)crashdumpmap); 2291} 2292 2293#define MAX_INIT_PT (96) 2294/* 2295 * pmap_object_init_pt preloads the ptes for a given object 2296 * into the specified pmap. This eliminates the blast of soft 2297 * faults on process startup and immediately after an mmap. 2298 */ 2299void 2300pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2301 vm_object_t object, vm_pindex_t pindex, 2302 vm_size_t size, int limit) 2303{ 2304 vm_offset_t tmpidx; 2305 int psize; 2306 vm_page_t p, mpte; 2307 int objpgs; 2308 2309 if (pmap == NULL || object == NULL) 2310 return; 2311 2312 /* 2313 * This code maps large physical mmap regions into the 2314 * processor address space. Note that some shortcuts 2315 * are taken, but the code works. 2316 */ 2317 if (pseflag && (object->type == OBJT_DEVICE) && 2318 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2319 int i; 2320 vm_page_t m[1]; 2321 unsigned int ptepindex; 2322 int npdes; 2323 pd_entry_t ptepa; 2324 2325 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2326 return; 2327 2328retry: 2329 p = vm_page_lookup(object, pindex); 2330 if (p && vm_page_sleep_busy(p, FALSE, "init4p")) 2331 goto retry; 2332 2333 if (p == NULL) { 2334 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2335 if (p == NULL) 2336 return; 2337 m[0] = p; 2338 2339 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2340 vm_page_lock_queues(); 2341 vm_page_free(p); 2342 vm_page_unlock_queues(); 2343 return; 2344 } 2345 2346 p = vm_page_lookup(object, pindex); 2347 vm_page_wakeup(p); 2348 } 2349 2350 ptepa = VM_PAGE_TO_PHYS(p); 2351 if (ptepa & (NBPDR - 1)) { 2352 return; 2353 } 2354 2355 p->valid = VM_PAGE_BITS_ALL; 2356 2357 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2358 npdes = size >> PDRSHIFT; 2359 for(i = 0; i < npdes; i++) { 2360 pmap->pm_pdir[ptepindex] = 2361 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2362 ptepa += NBPDR; 2363 ptepindex += 1; 2364 } 2365 vm_page_flag_set(p, PG_MAPPED); 2366 pmap_invalidate_all(kernel_pmap); 2367 return; 2368 } 2369 2370 psize = i386_btop(size); 2371 2372 if ((object->type != OBJT_VNODE) || 2373 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2374 (object->resident_page_count > MAX_INIT_PT))) { 2375 return; 2376 } 2377 2378 if (psize + pindex > object->size) { 2379 if (object->size < pindex) 2380 return; 2381 psize = object->size - pindex; 2382 } 2383 2384 mpte = NULL; 2385 /* 2386 * if we are processing a major portion of the object, then scan the 2387 * entire thing. 2388 */ 2389 if (psize > (object->resident_page_count >> 2)) { 2390 objpgs = psize; 2391 2392 for (p = TAILQ_FIRST(&object->memq); 2393 ((objpgs > 0) && (p != NULL)); 2394 p = TAILQ_NEXT(p, listq)) { 2395 2396 if (p->pindex < pindex || p->pindex - pindex >= psize) { 2397 continue; 2398 } 2399 tmpidx = p->pindex - pindex; 2400 /* 2401 * don't allow an madvise to blow away our really 2402 * free pages allocating pv entries. 2403 */ 2404 if ((limit & MAP_PREFAULT_MADVISE) && 2405 cnt.v_free_count < cnt.v_free_reserved) { 2406 break; 2407 } 2408 vm_page_lock_queues(); 2409 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2410 (p->busy == 0) && 2411 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2412 if ((p->queue - p->pc) == PQ_CACHE) 2413 vm_page_deactivate(p); 2414 vm_page_busy(p); 2415 vm_page_unlock_queues(); 2416 mpte = pmap_enter_quick(pmap, 2417 addr + i386_ptob(tmpidx), p, mpte); 2418 vm_page_lock_queues(); 2419 vm_page_flag_set(p, PG_MAPPED); 2420 vm_page_wakeup(p); 2421 } 2422 vm_page_unlock_queues(); 2423 objpgs -= 1; 2424 } 2425 } else { 2426 /* 2427 * else lookup the pages one-by-one. 2428 */ 2429 for (tmpidx = 0; tmpidx < psize; tmpidx += 1) { 2430 /* 2431 * don't allow an madvise to blow away our really 2432 * free pages allocating pv entries. 2433 */ 2434 if ((limit & MAP_PREFAULT_MADVISE) && 2435 cnt.v_free_count < cnt.v_free_reserved) { 2436 break; 2437 } 2438 p = vm_page_lookup(object, tmpidx + pindex); 2439 if (p == NULL) 2440 continue; 2441 vm_page_lock_queues(); 2442 if ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL && 2443 (p->busy == 0) && 2444 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2445 if ((p->queue - p->pc) == PQ_CACHE) 2446 vm_page_deactivate(p); 2447 vm_page_busy(p); 2448 vm_page_unlock_queues(); 2449 mpte = pmap_enter_quick(pmap, 2450 addr + i386_ptob(tmpidx), p, mpte); 2451 vm_page_lock_queues(); 2452 vm_page_flag_set(p, PG_MAPPED); 2453 vm_page_wakeup(p); 2454 } 2455 vm_page_unlock_queues(); 2456 } 2457 } 2458 return; 2459} 2460 2461/* 2462 * pmap_prefault provides a quick way of clustering 2463 * pagefaults into a processes address space. It is a "cousin" 2464 * of pmap_object_init_pt, except it runs at page fault time instead 2465 * of mmap time. 2466 */ 2467#define PFBAK 4 2468#define PFFOR 4 2469#define PAGEORDER_SIZE (PFBAK+PFFOR) 2470 2471static int pmap_prefault_pageorder[] = { 2472 -PAGE_SIZE, PAGE_SIZE, 2473 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2474 -3 * PAGE_SIZE, 3 * PAGE_SIZE 2475 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2476}; 2477 2478void 2479pmap_prefault(pmap, addra, entry) 2480 pmap_t pmap; 2481 vm_offset_t addra; 2482 vm_map_entry_t entry; 2483{ 2484 int i; 2485 vm_offset_t starta; 2486 vm_offset_t addr; 2487 vm_pindex_t pindex; 2488 vm_page_t m, mpte; 2489 vm_object_t object; 2490 2491 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2492 return; 2493 2494 object = entry->object.vm_object; 2495 2496 starta = addra - PFBAK * PAGE_SIZE; 2497 if (starta < entry->start) { 2498 starta = entry->start; 2499 } else if (starta > addra) { 2500 starta = 0; 2501 } 2502 2503 mpte = NULL; 2504 for (i = 0; i < PAGEORDER_SIZE; i++) { 2505 vm_object_t lobject; 2506 pt_entry_t *pte; 2507 2508 addr = addra + pmap_prefault_pageorder[i]; 2509 if (addr > addra + (PFFOR * PAGE_SIZE)) 2510 addr = 0; 2511 2512 if (addr < starta || addr >= entry->end) 2513 continue; 2514 2515 if ((*pmap_pde(pmap, addr)) == NULL) 2516 continue; 2517 2518 pte = vtopte(addr); 2519 if (*pte) 2520 continue; 2521 2522 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2523 lobject = object; 2524 for (m = vm_page_lookup(lobject, pindex); 2525 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2526 lobject = lobject->backing_object) { 2527 if (lobject->backing_object_offset & PAGE_MASK) 2528 break; 2529 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2530 m = vm_page_lookup(lobject->backing_object, pindex); 2531 } 2532 2533 /* 2534 * give-up when a page is not in memory 2535 */ 2536 if (m == NULL) 2537 break; 2538 vm_page_lock_queues(); 2539 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2540 (m->busy == 0) && 2541 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2542 2543 if ((m->queue - m->pc) == PQ_CACHE) { 2544 vm_page_deactivate(m); 2545 } 2546 vm_page_busy(m); 2547 vm_page_unlock_queues(); 2548 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2549 vm_page_lock_queues(); 2550 vm_page_flag_set(m, PG_MAPPED); 2551 vm_page_wakeup(m); 2552 } 2553 vm_page_unlock_queues(); 2554 } 2555} 2556 2557/* 2558 * Routine: pmap_change_wiring 2559 * Function: Change the wiring attribute for a map/virtual-address 2560 * pair. 2561 * In/out conditions: 2562 * The mapping must already exist in the pmap. 2563 */ 2564void 2565pmap_change_wiring(pmap, va, wired) 2566 register pmap_t pmap; 2567 vm_offset_t va; 2568 boolean_t wired; 2569{ 2570 register pt_entry_t *pte; 2571 2572 if (pmap == NULL) 2573 return; 2574 2575 pte = pmap_pte(pmap, va); 2576 2577 if (wired && !pmap_pte_w(pte)) 2578 pmap->pm_stats.wired_count++; 2579 else if (!wired && pmap_pte_w(pte)) 2580 pmap->pm_stats.wired_count--; 2581 2582 /* 2583 * Wiring is not a hardware characteristic so there is no need to 2584 * invalidate TLB. 2585 */ 2586 pmap_pte_set_w(pte, wired); 2587} 2588 2589 2590 2591/* 2592 * Copy the range specified by src_addr/len 2593 * from the source map to the range dst_addr/len 2594 * in the destination map. 2595 * 2596 * This routine is only advisory and need not do anything. 2597 */ 2598 2599void 2600pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2601 vm_offset_t src_addr) 2602{ 2603 vm_offset_t addr; 2604 vm_offset_t end_addr = src_addr + len; 2605 vm_offset_t pdnxt; 2606 pd_entry_t src_frame, dst_frame; 2607 vm_page_t m; 2608 2609 if (dst_addr != src_addr) 2610 return; 2611 2612 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2613 if (src_frame != (PTDpde & PG_FRAME)) 2614 return; 2615 2616 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2617 for (addr = src_addr; addr < end_addr; addr = pdnxt) { 2618 pt_entry_t *src_pte, *dst_pte; 2619 vm_page_t dstmpte, srcmpte; 2620 pd_entry_t srcptepaddr; 2621 unsigned ptepindex; 2622 2623 if (addr >= UPT_MIN_ADDRESS) 2624 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2625 2626 /* 2627 * Don't let optional prefaulting of pages make us go 2628 * way below the low water mark of free pages or way 2629 * above high water mark of used pv entries. 2630 */ 2631 if (cnt.v_free_count < cnt.v_free_reserved || 2632 pv_entry_count > pv_entry_high_water) 2633 break; 2634 2635 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2636 ptepindex = addr >> PDRSHIFT; 2637 2638 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2639 if (srcptepaddr == 0) 2640 continue; 2641 2642 if (srcptepaddr & PG_PS) { 2643 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2644 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2645 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2646 } 2647 continue; 2648 } 2649 2650 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2651 if ((srcmpte == NULL) || 2652 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2653 continue; 2654 2655 if (pdnxt > end_addr) 2656 pdnxt = end_addr; 2657 2658 /* 2659 * Have to recheck this before every avtopte() call below 2660 * in case we have blocked and something else used APTDpde. 2661 */ 2662 if (dst_frame != (APTDpde & PG_FRAME)) { 2663 APTDpde = dst_frame | PG_RW | PG_V; 2664 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 2665 } 2666 src_pte = vtopte(addr); 2667 dst_pte = avtopte(addr); 2668 while (addr < pdnxt) { 2669 pt_entry_t ptetemp; 2670 ptetemp = *src_pte; 2671 /* 2672 * we only virtual copy managed pages 2673 */ 2674 if ((ptetemp & PG_MANAGED) != 0) { 2675 /* 2676 * We have to check after allocpte for the 2677 * pte still being around... allocpte can 2678 * block. 2679 */ 2680 dstmpte = pmap_allocpte(dst_pmap, addr); 2681 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2682 /* 2683 * Clear the modified and 2684 * accessed (referenced) bits 2685 * during the copy. 2686 */ 2687 m = PHYS_TO_VM_PAGE(ptetemp); 2688 *dst_pte = ptetemp & ~(PG_M | PG_A); 2689 dst_pmap->pm_stats.resident_count++; 2690 pmap_insert_entry(dst_pmap, addr, 2691 dstmpte, m); 2692 } else { 2693 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2694 } 2695 if (dstmpte->hold_count >= srcmpte->hold_count) 2696 break; 2697 } 2698 addr += PAGE_SIZE; 2699 src_pte++; 2700 dst_pte++; 2701 } 2702 } 2703} 2704 2705#ifdef SMP 2706 2707/* 2708 * pmap_zpi_switchin*() 2709 * 2710 * These functions allow us to avoid doing IPIs alltogether in certain 2711 * temporary page-mapping situations (page zeroing). Instead to deal 2712 * with being preempted and moved onto a different cpu we invalidate 2713 * the page when the scheduler switches us in. This does not occur 2714 * very often so we remain relatively optimal with very little effort. 2715 */ 2716static void 2717pmap_zpi_switchin12(void) 2718{ 2719 invlpg((u_int)CADDR1); 2720 invlpg((u_int)CADDR2); 2721} 2722 2723static void 2724pmap_zpi_switchin2(void) 2725{ 2726 invlpg((u_int)CADDR2); 2727} 2728 2729static void 2730pmap_zpi_switchin3(void) 2731{ 2732 invlpg((u_int)CADDR3); 2733} 2734 2735#endif 2736 2737/* 2738 * pmap_zero_page zeros the specified hardware page by mapping 2739 * the page into KVM and using bzero to clear its contents. 2740 */ 2741void 2742pmap_zero_page(vm_page_t m) 2743{ 2744 vm_offset_t phys; 2745 2746 phys = VM_PAGE_TO_PHYS(m); 2747 if (*CMAP2) 2748 panic("pmap_zero_page: CMAP2 busy"); 2749 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2750#ifdef I386_CPU 2751 invltlb(); 2752#else 2753#ifdef SMP 2754 curthread->td_switchin = pmap_zpi_switchin2; 2755#endif 2756 invlpg((u_int)CADDR2); 2757#endif 2758#if defined(I686_CPU) 2759 if (cpu_class == CPUCLASS_686) 2760 i686_pagezero(CADDR2); 2761 else 2762#endif 2763 bzero(CADDR2, PAGE_SIZE); 2764#ifdef SMP 2765 curthread->td_switchin = NULL; 2766#endif 2767 *CMAP2 = 0; 2768} 2769 2770/* 2771 * pmap_zero_page_area zeros the specified hardware page by mapping 2772 * the page into KVM and using bzero to clear its contents. 2773 * 2774 * off and size may not cover an area beyond a single hardware page. 2775 */ 2776void 2777pmap_zero_page_area(vm_page_t m, int off, int size) 2778{ 2779 vm_offset_t phys; 2780 2781 phys = VM_PAGE_TO_PHYS(m); 2782 if (*CMAP2) 2783 panic("pmap_zero_page: CMAP2 busy"); 2784 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2785#ifdef I386_CPU 2786 invltlb(); 2787#else 2788#ifdef SMP 2789 curthread->td_switchin = pmap_zpi_switchin2; 2790#endif 2791 invlpg((u_int)CADDR2); 2792#endif 2793#if defined(I686_CPU) 2794 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2795 i686_pagezero(CADDR2); 2796 else 2797#endif 2798 bzero((char *)CADDR2 + off, size); 2799#ifdef SMP 2800 curthread->td_switchin = NULL; 2801#endif 2802 *CMAP2 = 0; 2803} 2804 2805/* 2806 * pmap_zero_page_idle zeros the specified hardware page by mapping 2807 * the page into KVM and using bzero to clear its contents. This 2808 * is intended to be called from the vm_pagezero process only and 2809 * outside of Giant. 2810 */ 2811void 2812pmap_zero_page_idle(vm_page_t m) 2813{ 2814 vm_offset_t phys; 2815 2816 phys = VM_PAGE_TO_PHYS(m); 2817 if (*CMAP3) 2818 panic("pmap_zero_page: CMAP3 busy"); 2819 *CMAP3 = PG_V | PG_RW | phys | PG_A | PG_M; 2820#ifdef I386_CPU 2821 invltlb(); 2822#else 2823#ifdef SMP 2824 curthread->td_switchin = pmap_zpi_switchin3; 2825#endif 2826 invlpg((u_int)CADDR3); 2827#endif 2828#if defined(I686_CPU) 2829 if (cpu_class == CPUCLASS_686) 2830 i686_pagezero(CADDR3); 2831 else 2832#endif 2833 bzero(CADDR3, PAGE_SIZE); 2834#ifdef SMP 2835 curthread->td_switchin = NULL; 2836#endif 2837 *CMAP3 = 0; 2838} 2839 2840/* 2841 * pmap_copy_page copies the specified (machine independent) 2842 * page by mapping the page into virtual memory and using 2843 * bcopy to copy the page, one machine dependent page at a 2844 * time. 2845 */ 2846void 2847pmap_copy_page(vm_page_t src, vm_page_t dst) 2848{ 2849 2850 if (*CMAP1) 2851 panic("pmap_copy_page: CMAP1 busy"); 2852 if (*CMAP2) 2853 panic("pmap_copy_page: CMAP2 busy"); 2854 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2855 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2856#ifdef I386_CPU 2857 invltlb(); 2858#else 2859#ifdef SMP 2860 curthread->td_switchin = pmap_zpi_switchin12; 2861#endif 2862 invlpg((u_int)CADDR1); 2863 invlpg((u_int)CADDR2); 2864#endif 2865 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2866#ifdef SMP 2867 curthread->td_switchin = NULL; 2868#endif 2869 *CMAP1 = 0; 2870 *CMAP2 = 0; 2871} 2872 2873 2874/* 2875 * Routine: pmap_pageable 2876 * Function: 2877 * Make the specified pages (by pmap, offset) 2878 * pageable (or not) as requested. 2879 * 2880 * A page which is not pageable may not take 2881 * a fault; therefore, its page table entry 2882 * must remain valid for the duration. 2883 * 2884 * This routine is merely advisory; pmap_enter 2885 * will specify that these pages are to be wired 2886 * down (or not) as appropriate. 2887 */ 2888void 2889pmap_pageable(pmap, sva, eva, pageable) 2890 pmap_t pmap; 2891 vm_offset_t sva, eva; 2892 boolean_t pageable; 2893{ 2894} 2895 2896/* 2897 * Returns true if the pmap's pv is one of the first 2898 * 16 pvs linked to from this page. This count may 2899 * be changed upwards or downwards in the future; it 2900 * is only necessary that true be returned for a small 2901 * subset of pmaps for proper page aging. 2902 */ 2903boolean_t 2904pmap_page_exists_quick(pmap, m) 2905 pmap_t pmap; 2906 vm_page_t m; 2907{ 2908 pv_entry_t pv; 2909 int loops = 0; 2910 int s; 2911 2912 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2913 return FALSE; 2914 2915 s = splvm(); 2916 2917 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2918 if (pv->pv_pmap == pmap) { 2919 splx(s); 2920 return TRUE; 2921 } 2922 loops++; 2923 if (loops >= 16) 2924 break; 2925 } 2926 splx(s); 2927 return (FALSE); 2928} 2929 2930#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2931/* 2932 * Remove all pages from specified address space 2933 * this aids process exit speeds. Also, this code 2934 * is special cased for current process only, but 2935 * can have the more generic (and slightly slower) 2936 * mode enabled. This is much faster than pmap_remove 2937 * in the case of running down an entire address space. 2938 */ 2939void 2940pmap_remove_pages(pmap, sva, eva) 2941 pmap_t pmap; 2942 vm_offset_t sva, eva; 2943{ 2944 pt_entry_t *pte, tpte; 2945 vm_page_t m; 2946 pv_entry_t pv, npv; 2947 int s; 2948 2949#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2950 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2951 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2952 return; 2953 } 2954#endif 2955 2956 s = splvm(); 2957 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2958 2959 if (pv->pv_va >= eva || pv->pv_va < sva) { 2960 npv = TAILQ_NEXT(pv, pv_plist); 2961 continue; 2962 } 2963 2964#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2965 pte = vtopte(pv->pv_va); 2966#else 2967 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2968#endif 2969 tpte = *pte; 2970 2971 if (tpte == 0) { 2972 printf("TPTE at %p IS ZERO @ VA %08x\n", 2973 pte, pv->pv_va); 2974 panic("bad pte"); 2975 } 2976 2977/* 2978 * We cannot remove wired pages from a process' mapping at this time 2979 */ 2980 if (tpte & PG_W) { 2981 npv = TAILQ_NEXT(pv, pv_plist); 2982 continue; 2983 } 2984 2985 m = PHYS_TO_VM_PAGE(tpte); 2986 KASSERT(m->phys_addr == (tpte & PG_FRAME), 2987 ("vm_page_t %p phys_addr mismatch %08x %08x", 2988 m, m->phys_addr, tpte)); 2989 2990 KASSERT(m < &vm_page_array[vm_page_array_size], 2991 ("pmap_remove_pages: bad tpte %x", tpte)); 2992 2993 pv->pv_pmap->pm_stats.resident_count--; 2994 2995 *pte = 0; 2996 2997 /* 2998 * Update the vm_page_t clean and reference bits. 2999 */ 3000 if (tpte & PG_M) { 3001 vm_page_dirty(m); 3002 } 3003 3004 npv = TAILQ_NEXT(pv, pv_plist); 3005 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 3006 3007 m->md.pv_list_count--; 3008 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3009 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 3010 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 3011 } 3012 3013 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 3014 free_pv_entry(pv); 3015 } 3016 splx(s); 3017 pmap_invalidate_all(pmap); 3018} 3019 3020/* 3021 * pmap_testbit tests bits in pte's 3022 * note that the testbit/changebit routines are inline, 3023 * and a lot of things compile-time evaluate. 3024 */ 3025static boolean_t 3026pmap_testbit(m, bit) 3027 vm_page_t m; 3028 int bit; 3029{ 3030 pv_entry_t pv; 3031 pt_entry_t *pte; 3032 int s; 3033 3034 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3035 return FALSE; 3036 3037 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 3038 return FALSE; 3039 3040 s = splvm(); 3041 3042 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3043 /* 3044 * if the bit being tested is the modified bit, then 3045 * mark clean_map and ptes as never 3046 * modified. 3047 */ 3048 if (bit & (PG_A|PG_M)) { 3049 if (!pmap_track_modified(pv->pv_va)) 3050 continue; 3051 } 3052 3053#if defined(PMAP_DIAGNOSTIC) 3054 if (!pv->pv_pmap) { 3055 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3056 continue; 3057 } 3058#endif 3059 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3060 if (*pte & bit) { 3061 splx(s); 3062 return TRUE; 3063 } 3064 } 3065 splx(s); 3066 return (FALSE); 3067} 3068 3069/* 3070 * this routine is used to modify bits in ptes 3071 */ 3072static __inline void 3073pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3074{ 3075 register pv_entry_t pv; 3076 register pt_entry_t *pte; 3077 int s; 3078 3079 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3080 return; 3081 3082 s = splvm(); 3083 3084 /* 3085 * Loop over all current mappings setting/clearing as appropos If 3086 * setting RO do we need to clear the VAC? 3087 */ 3088 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3089 /* 3090 * don't write protect pager mappings 3091 */ 3092 if (!setem && (bit == PG_RW)) { 3093 if (!pmap_track_modified(pv->pv_va)) 3094 continue; 3095 } 3096 3097#if defined(PMAP_DIAGNOSTIC) 3098 if (!pv->pv_pmap) { 3099 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3100 continue; 3101 } 3102#endif 3103 3104 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3105 3106 if (setem) { 3107 *pte |= bit; 3108 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3109 } else { 3110 pt_entry_t pbits = *pte; 3111 if (pbits & bit) { 3112 if (bit == PG_RW) { 3113 if (pbits & PG_M) { 3114 vm_page_dirty(m); 3115 } 3116 *pte = pbits & ~(PG_M|PG_RW); 3117 } else { 3118 *pte = pbits & ~bit; 3119 } 3120 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3121 } 3122 } 3123 } 3124 splx(s); 3125} 3126 3127/* 3128 * pmap_page_protect: 3129 * 3130 * Lower the permission for all mappings to a given page. 3131 */ 3132void 3133pmap_page_protect(vm_page_t m, vm_prot_t prot) 3134{ 3135 if ((prot & VM_PROT_WRITE) == 0) { 3136 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3137 pmap_changebit(m, PG_RW, FALSE); 3138 } else { 3139 pmap_remove_all(m); 3140 } 3141 } 3142} 3143 3144vm_offset_t 3145pmap_phys_address(ppn) 3146 int ppn; 3147{ 3148 return (i386_ptob(ppn)); 3149} 3150 3151/* 3152 * pmap_ts_referenced: 3153 * 3154 * Return a count of reference bits for a page, clearing those bits. 3155 * It is not necessary for every reference bit to be cleared, but it 3156 * is necessary that 0 only be returned when there are truly no 3157 * reference bits set. 3158 * 3159 * XXX: The exact number of bits to check and clear is a matter that 3160 * should be tested and standardized at some point in the future for 3161 * optimal aging of shared pages. 3162 */ 3163int 3164pmap_ts_referenced(vm_page_t m) 3165{ 3166 register pv_entry_t pv, pvf, pvn; 3167 pt_entry_t *pte; 3168 int s; 3169 int rtval = 0; 3170 3171 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3172 return (rtval); 3173 3174 s = splvm(); 3175 3176 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3177 3178 pvf = pv; 3179 3180 do { 3181 pvn = TAILQ_NEXT(pv, pv_list); 3182 3183 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3184 3185 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3186 3187 if (!pmap_track_modified(pv->pv_va)) 3188 continue; 3189 3190 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3191 3192 if (pte && (*pte & PG_A)) { 3193 *pte &= ~PG_A; 3194 3195 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3196 3197 rtval++; 3198 if (rtval > 4) { 3199 break; 3200 } 3201 } 3202 } while ((pv = pvn) != NULL && pv != pvf); 3203 } 3204 splx(s); 3205 3206 return (rtval); 3207} 3208 3209/* 3210 * pmap_is_modified: 3211 * 3212 * Return whether or not the specified physical page was modified 3213 * in any physical maps. 3214 */ 3215boolean_t 3216pmap_is_modified(vm_page_t m) 3217{ 3218 return pmap_testbit(m, PG_M); 3219} 3220 3221/* 3222 * Clear the modify bits on the specified physical page. 3223 */ 3224void 3225pmap_clear_modify(vm_page_t m) 3226{ 3227 pmap_changebit(m, PG_M, FALSE); 3228} 3229 3230/* 3231 * pmap_clear_reference: 3232 * 3233 * Clear the reference bit on the specified physical page. 3234 */ 3235void 3236pmap_clear_reference(vm_page_t m) 3237{ 3238 pmap_changebit(m, PG_A, FALSE); 3239} 3240 3241/* 3242 * Miscellaneous support routines follow 3243 */ 3244 3245static void 3246i386_protection_init() 3247{ 3248 register int *kp, prot; 3249 3250 kp = protection_codes; 3251 for (prot = 0; prot < 8; prot++) { 3252 switch (prot) { 3253 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3254 /* 3255 * Read access is also 0. There isn't any execute bit, 3256 * so just make it readable. 3257 */ 3258 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3259 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3260 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3261 *kp++ = 0; 3262 break; 3263 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3264 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3265 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3266 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3267 *kp++ = PG_RW; 3268 break; 3269 } 3270 } 3271} 3272 3273/* 3274 * Map a set of physical memory pages into the kernel virtual 3275 * address space. Return a pointer to where it is mapped. This 3276 * routine is intended to be used for mapping device memory, 3277 * NOT real memory. 3278 */ 3279void * 3280pmap_mapdev(pa, size) 3281 vm_offset_t pa; 3282 vm_size_t size; 3283{ 3284 vm_offset_t va, tmpva, offset; 3285 pt_entry_t *pte; 3286 3287 offset = pa & PAGE_MASK; 3288 size = roundup(offset + size, PAGE_SIZE); 3289 3290 GIANT_REQUIRED; 3291 3292 va = kmem_alloc_pageable(kernel_map, size); 3293 if (!va) 3294 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3295 3296 pa = pa & PG_FRAME; 3297 for (tmpva = va; size > 0; ) { 3298 pte = vtopte(tmpva); 3299 *pte = pa | PG_RW | PG_V | pgeflag; 3300 size -= PAGE_SIZE; 3301 tmpva += PAGE_SIZE; 3302 pa += PAGE_SIZE; 3303 } 3304 pmap_invalidate_range(kernel_pmap, va, tmpva); 3305 return ((void *)(va + offset)); 3306} 3307 3308void 3309pmap_unmapdev(va, size) 3310 vm_offset_t va; 3311 vm_size_t size; 3312{ 3313 vm_offset_t base, offset, tmpva; 3314 pt_entry_t *pte; 3315 3316 base = va & PG_FRAME; 3317 offset = va & PAGE_MASK; 3318 size = roundup(offset + size, PAGE_SIZE); 3319 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE) { 3320 pte = vtopte(tmpva); 3321 *pte = 0; 3322 } 3323 pmap_invalidate_range(kernel_pmap, va, tmpva); 3324 kmem_free(kernel_map, base, size); 3325} 3326 3327/* 3328 * perform the pmap work for mincore 3329 */ 3330int 3331pmap_mincore(pmap, addr) 3332 pmap_t pmap; 3333 vm_offset_t addr; 3334{ 3335 pt_entry_t *ptep, pte; 3336 vm_page_t m; 3337 int val = 0; 3338 3339 ptep = pmap_pte(pmap, addr); 3340 if (ptep == 0) { 3341 return 0; 3342 } 3343 3344 if ((pte = *ptep) != 0) { 3345 vm_offset_t pa; 3346 3347 val = MINCORE_INCORE; 3348 if ((pte & PG_MANAGED) == 0) 3349 return val; 3350 3351 pa = pte & PG_FRAME; 3352 3353 m = PHYS_TO_VM_PAGE(pa); 3354 3355 /* 3356 * Modified by us 3357 */ 3358 if (pte & PG_M) 3359 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3360 /* 3361 * Modified by someone 3362 */ 3363 else if (m->dirty || pmap_is_modified(m)) 3364 val |= MINCORE_MODIFIED_OTHER; 3365 /* 3366 * Referenced by us 3367 */ 3368 if (pte & PG_A) 3369 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3370 3371 /* 3372 * Referenced by someone 3373 */ 3374 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3375 val |= MINCORE_REFERENCED_OTHER; 3376 vm_page_flag_set(m, PG_REFERENCED); 3377 } 3378 } 3379 return val; 3380} 3381 3382void 3383pmap_activate(struct thread *td) 3384{ 3385 struct proc *p = td->td_proc; 3386 pmap_t pmap; 3387 u_int32_t cr3; 3388 3389 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3390#if defined(SMP) 3391 pmap->pm_active |= PCPU_GET(cpumask); 3392#else 3393 pmap->pm_active |= 1; 3394#endif 3395 cr3 = vtophys(pmap->pm_pdir); 3396 /* XXXKSE this is wrong. 3397 * pmap_activate is for the current thread on the current cpu 3398 */ 3399 if (p->p_flag & P_KSES) { 3400 /* Make sure all other cr3 entries are updated. */ 3401 /* what if they are running? XXXKSE (maybe abort them) */ 3402 FOREACH_THREAD_IN_PROC(p, td) { 3403 td->td_pcb->pcb_cr3 = cr3; 3404 } 3405 } else { 3406 td->td_pcb->pcb_cr3 = cr3; 3407 } 3408 load_cr3(cr3); 3409#ifdef SWTCH_OPTIM_STATS 3410 tlb_flush_count++; 3411#endif 3412} 3413 3414vm_offset_t 3415pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3416{ 3417 3418 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3419 return addr; 3420 } 3421 3422 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3423 return addr; 3424} 3425 3426 3427#if defined(PMAP_DEBUG) 3428pmap_pid_dump(int pid) 3429{ 3430 pmap_t pmap; 3431 struct proc *p; 3432 int npte = 0; 3433 int index; 3434 3435 sx_slock(&allproc_lock); 3436 LIST_FOREACH(p, &allproc, p_list) { 3437 if (p->p_pid != pid) 3438 continue; 3439 3440 if (p->p_vmspace) { 3441 int i,j; 3442 index = 0; 3443 pmap = vmspace_pmap(p->p_vmspace); 3444 for (i = 0; i < NPDEPG; i++) { 3445 pd_entry_t *pde; 3446 pt_entry_t *pte; 3447 vm_offset_t base = i << PDRSHIFT; 3448 3449 pde = &pmap->pm_pdir[i]; 3450 if (pde && pmap_pde_v(pde)) { 3451 for (j = 0; j < NPTEPG; j++) { 3452 vm_offset_t va = base + (j << PAGE_SHIFT); 3453 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3454 if (index) { 3455 index = 0; 3456 printf("\n"); 3457 } 3458 sx_sunlock(&allproc_lock); 3459 return npte; 3460 } 3461 pte = pmap_pte_quick(pmap, va); 3462 if (pte && pmap_pte_v(pte)) { 3463 pt_entry_t pa; 3464 vm_page_t m; 3465 pa = *pte; 3466 m = PHYS_TO_VM_PAGE(pa); 3467 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3468 va, pa, m->hold_count, m->wire_count, m->flags); 3469 npte++; 3470 index++; 3471 if (index >= 2) { 3472 index = 0; 3473 printf("\n"); 3474 } else { 3475 printf(" "); 3476 } 3477 } 3478 } 3479 } 3480 } 3481 } 3482 } 3483 sx_sunlock(&allproc_lock); 3484 return npte; 3485} 3486#endif 3487 3488#if defined(DEBUG) 3489 3490static void pads(pmap_t pm); 3491void pmap_pvdump(vm_offset_t pa); 3492 3493/* print address space of pmap*/ 3494static void 3495pads(pm) 3496 pmap_t pm; 3497{ 3498 int i, j; 3499 vm_offset_t va; 3500 pt_entry_t *ptep; 3501 3502 if (pm == kernel_pmap) 3503 return; 3504 for (i = 0; i < NPDEPG; i++) 3505 if (pm->pm_pdir[i]) 3506 for (j = 0; j < NPTEPG; j++) { 3507 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3508 if (pm == kernel_pmap && va < KERNBASE) 3509 continue; 3510 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3511 continue; 3512 ptep = pmap_pte_quick(pm, va); 3513 if (pmap_pte_v(ptep)) 3514 printf("%x:%x ", va, *ptep); 3515 }; 3516 3517} 3518 3519void 3520pmap_pvdump(pa) 3521 vm_offset_t pa; 3522{ 3523 pv_entry_t pv; 3524 vm_page_t m; 3525 3526 printf("pa %x", pa); 3527 m = PHYS_TO_VM_PAGE(pa); 3528 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3529 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3530 pads(pv->pv_pmap); 3531 } 3532 printf(" "); 3533} 3534#endif 3535