pmap.c revision 101254
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 101254 2002-08-03 06:42:30Z 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_wakeup(m); 1368 1369 return m; 1370} 1371 1372static vm_page_t 1373pmap_allocpte(pmap_t pmap, vm_offset_t va) 1374{ 1375 unsigned ptepindex; 1376 pd_entry_t ptepa; 1377 vm_page_t m; 1378 1379 /* 1380 * Calculate pagetable page index 1381 */ 1382 ptepindex = va >> PDRSHIFT; 1383 1384 /* 1385 * Get the page directory entry 1386 */ 1387 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1388 1389 /* 1390 * This supports switching from a 4MB page to a 1391 * normal 4K page. 1392 */ 1393 if (ptepa & PG_PS) { 1394 pmap->pm_pdir[ptepindex] = 0; 1395 ptepa = 0; 1396 pmap_invalidate_all(kernel_pmap); 1397 } 1398 1399 /* 1400 * If the page table page is mapped, we just increment the 1401 * hold count, and activate it. 1402 */ 1403 if (ptepa) { 1404 /* 1405 * In order to get the page table page, try the 1406 * hint first. 1407 */ 1408 if (pmap->pm_ptphint && 1409 (pmap->pm_ptphint->pindex == ptepindex)) { 1410 m = pmap->pm_ptphint; 1411 } else { 1412 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1413 pmap->pm_ptphint = m; 1414 } 1415 m->hold_count++; 1416 return m; 1417 } 1418 /* 1419 * Here if the pte page isn't mapped, or if it has been deallocated. 1420 */ 1421 return _pmap_allocpte(pmap, ptepindex); 1422} 1423 1424 1425/*************************************************** 1426* Pmap allocation/deallocation routines. 1427 ***************************************************/ 1428 1429/* 1430 * Release any resources held by the given physical map. 1431 * Called when a pmap initialized by pmap_pinit is being released. 1432 * Should only be called if the map contains no valid mappings. 1433 */ 1434void 1435pmap_release(pmap_t pmap) 1436{ 1437 vm_page_t p,n,ptdpg; 1438 vm_object_t object = pmap->pm_pteobj; 1439 int curgeneration; 1440 1441#if defined(DIAGNOSTIC) 1442 if (object->ref_count != 1) 1443 panic("pmap_release: pteobj reference count != 1"); 1444#endif 1445 1446 ptdpg = NULL; 1447 LIST_REMOVE(pmap, pm_list); 1448retry: 1449 curgeneration = object->generation; 1450 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1451 n = TAILQ_NEXT(p, listq); 1452 if (p->pindex == PTDPTDI) { 1453 ptdpg = p; 1454 continue; 1455 } 1456 while (1) { 1457 if (!pmap_release_free_page(pmap, p) && 1458 (object->generation != curgeneration)) 1459 goto retry; 1460 } 1461 } 1462 1463 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1464 goto retry; 1465} 1466 1467static int 1468kvm_size(SYSCTL_HANDLER_ARGS) 1469{ 1470 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1471 1472 return sysctl_handle_long(oidp, &ksize, 0, req); 1473} 1474SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1475 0, 0, kvm_size, "IU", "Size of KVM"); 1476 1477static int 1478kvm_free(SYSCTL_HANDLER_ARGS) 1479{ 1480 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1481 1482 return sysctl_handle_long(oidp, &kfree, 0, req); 1483} 1484SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1485 0, 0, kvm_free, "IU", "Amount of KVM free"); 1486 1487/* 1488 * grow the number of kernel page table entries, if needed 1489 */ 1490void 1491pmap_growkernel(vm_offset_t addr) 1492{ 1493 struct pmap *pmap; 1494 int s; 1495 vm_offset_t ptppaddr; 1496 vm_page_t nkpg; 1497 pd_entry_t newpdir; 1498 1499 s = splhigh(); 1500 if (kernel_vm_end == 0) { 1501 kernel_vm_end = KERNBASE; 1502 nkpt = 0; 1503 while (pdir_pde(PTD, kernel_vm_end)) { 1504 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1505 nkpt++; 1506 } 1507 } 1508 addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1509 while (kernel_vm_end < addr) { 1510 if (pdir_pde(PTD, kernel_vm_end)) { 1511 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1512 continue; 1513 } 1514 1515 /* 1516 * This index is bogus, but out of the way 1517 */ 1518 nkpg = vm_page_alloc(kptobj, nkpt, 1519 VM_ALLOC_SYSTEM | VM_ALLOC_WIRED); 1520 if (!nkpg) 1521 panic("pmap_growkernel: no memory to grow kernel"); 1522 1523 nkpt++; 1524 1525 pmap_zero_page(nkpg); 1526 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1527 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1528 pdir_pde(PTD, kernel_vm_end) = newpdir; 1529 1530 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1531 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1532 } 1533 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1534 } 1535 splx(s); 1536} 1537 1538 1539/*************************************************** 1540 * page management routines. 1541 ***************************************************/ 1542 1543/* 1544 * free the pv_entry back to the free list 1545 */ 1546static PMAP_INLINE void 1547free_pv_entry(pv_entry_t pv) 1548{ 1549 pv_entry_count--; 1550 uma_zfree(pvzone, pv); 1551} 1552 1553/* 1554 * get a new pv_entry, allocating a block from the system 1555 * when needed. 1556 * the memory allocation is performed bypassing the malloc code 1557 * because of the possibility of allocations at interrupt time. 1558 */ 1559static pv_entry_t 1560get_pv_entry(void) 1561{ 1562 pv_entry_count++; 1563 if (pv_entry_high_water && 1564 (pv_entry_count > pv_entry_high_water) && 1565 (pmap_pagedaemon_waken == 0)) { 1566 pmap_pagedaemon_waken = 1; 1567 wakeup (&vm_pages_needed); 1568 } 1569 return uma_zalloc(pvzone, M_NOWAIT); 1570} 1571 1572/* 1573 * This routine is very drastic, but can save the system 1574 * in a pinch. 1575 */ 1576void 1577pmap_collect() 1578{ 1579 int i; 1580 vm_page_t m; 1581 static int warningdone = 0; 1582 1583 if (pmap_pagedaemon_waken == 0) 1584 return; 1585 1586 if (warningdone < 5) { 1587 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1588 warningdone++; 1589 } 1590 1591 for(i = 0; i < vm_page_array_size; i++) { 1592 m = &vm_page_array[i]; 1593 if (m->wire_count || m->hold_count || m->busy || 1594 (m->flags & (PG_BUSY | PG_UNMANAGED))) 1595 continue; 1596 pmap_remove_all(m); 1597 } 1598 pmap_pagedaemon_waken = 0; 1599} 1600 1601 1602/* 1603 * If it is the first entry on the list, it is actually 1604 * in the header and we must copy the following entry up 1605 * to the header. Otherwise we must search the list for 1606 * the entry. In either case we free the now unused entry. 1607 */ 1608 1609static int 1610pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1611{ 1612 pv_entry_t pv; 1613 int rtval; 1614 int s; 1615 1616 s = splvm(); 1617 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1618 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1619 if (pmap == pv->pv_pmap && va == pv->pv_va) 1620 break; 1621 } 1622 } else { 1623 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1624 if (va == pv->pv_va) 1625 break; 1626 } 1627 } 1628 1629 rtval = 0; 1630 if (pv) { 1631 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1632 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1633 m->md.pv_list_count--; 1634 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1635 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1636 1637 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1638 free_pv_entry(pv); 1639 } 1640 1641 splx(s); 1642 return rtval; 1643} 1644 1645/* 1646 * Create a pv entry for page at pa for 1647 * (pmap, va). 1648 */ 1649static void 1650pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1651{ 1652 1653 int s; 1654 pv_entry_t pv; 1655 1656 s = splvm(); 1657 pv = get_pv_entry(); 1658 pv->pv_va = va; 1659 pv->pv_pmap = pmap; 1660 pv->pv_ptem = mpte; 1661 1662 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1663 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1664 m->md.pv_list_count++; 1665 1666 splx(s); 1667} 1668 1669/* 1670 * pmap_remove_pte: do the things to unmap a page in a process 1671 */ 1672static int 1673pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1674{ 1675 pt_entry_t oldpte; 1676 vm_page_t m; 1677 1678 oldpte = atomic_readandclear_int(ptq); 1679 if (oldpte & PG_W) 1680 pmap->pm_stats.wired_count -= 1; 1681 /* 1682 * Machines that don't support invlpg, also don't support 1683 * PG_G. 1684 */ 1685 if (oldpte & PG_G) 1686 pmap_invalidate_page(kernel_pmap, va); 1687 pmap->pm_stats.resident_count -= 1; 1688 if (oldpte & PG_MANAGED) { 1689 m = PHYS_TO_VM_PAGE(oldpte); 1690 if (oldpte & PG_M) { 1691#if defined(PMAP_DIAGNOSTIC) 1692 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1693 printf( 1694 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1695 va, oldpte); 1696 } 1697#endif 1698 if (pmap_track_modified(va)) 1699 vm_page_dirty(m); 1700 } 1701 if (oldpte & PG_A) 1702 vm_page_flag_set(m, PG_REFERENCED); 1703 return pmap_remove_entry(pmap, m, va); 1704 } else { 1705 return pmap_unuse_pt(pmap, va, NULL); 1706 } 1707 1708 return 0; 1709} 1710 1711/* 1712 * Remove a single page from a process address space 1713 */ 1714static void 1715pmap_remove_page(pmap_t pmap, vm_offset_t va) 1716{ 1717 register pt_entry_t *ptq; 1718 1719 /* 1720 * if there is no pte for this address, just skip it!!! 1721 */ 1722 if (*pmap_pde(pmap, va) == 0) { 1723 return; 1724 } 1725 1726 /* 1727 * get a local va for mappings for this pmap. 1728 */ 1729 ptq = get_ptbase(pmap) + i386_btop(va); 1730 if (*ptq) { 1731 (void) pmap_remove_pte(pmap, ptq, va); 1732 pmap_invalidate_page(pmap, va); 1733 } 1734 return; 1735} 1736 1737/* 1738 * Remove the given range of addresses from the specified map. 1739 * 1740 * It is assumed that the start and end are properly 1741 * rounded to the page size. 1742 */ 1743void 1744pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1745{ 1746 register pt_entry_t *ptbase; 1747 vm_offset_t pdnxt; 1748 pd_entry_t ptpaddr; 1749 vm_offset_t sindex, eindex; 1750 int anyvalid; 1751 1752 if (pmap == NULL) 1753 return; 1754 1755 if (pmap->pm_stats.resident_count == 0) 1756 return; 1757 1758 /* 1759 * special handling of removing one page. a very 1760 * common operation and easy to short circuit some 1761 * code. 1762 */ 1763 if ((sva + PAGE_SIZE == eva) && 1764 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1765 pmap_remove_page(pmap, sva); 1766 return; 1767 } 1768 1769 anyvalid = 0; 1770 1771 /* 1772 * Get a local virtual address for the mappings that are being 1773 * worked with. 1774 */ 1775 ptbase = get_ptbase(pmap); 1776 1777 sindex = i386_btop(sva); 1778 eindex = i386_btop(eva); 1779 1780 for (; sindex < eindex; sindex = pdnxt) { 1781 unsigned pdirindex; 1782 1783 /* 1784 * Calculate index for next page table. 1785 */ 1786 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1787 if (pmap->pm_stats.resident_count == 0) 1788 break; 1789 1790 pdirindex = sindex / NPDEPG; 1791 ptpaddr = pmap->pm_pdir[pdirindex]; 1792 if ((ptpaddr & PG_PS) != 0) { 1793 pmap->pm_pdir[pdirindex] = 0; 1794 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1795 anyvalid++; 1796 continue; 1797 } 1798 1799 /* 1800 * Weed out invalid mappings. Note: we assume that the page 1801 * directory table is always allocated, and in kernel virtual. 1802 */ 1803 if (ptpaddr == 0) 1804 continue; 1805 1806 /* 1807 * Limit our scan to either the end of the va represented 1808 * by the current page table page, or to the end of the 1809 * range being removed. 1810 */ 1811 if (pdnxt > eindex) { 1812 pdnxt = eindex; 1813 } 1814 1815 for (; sindex != pdnxt; sindex++) { 1816 vm_offset_t va; 1817 if (ptbase[sindex] == 0) { 1818 continue; 1819 } 1820 va = i386_ptob(sindex); 1821 1822 anyvalid++; 1823 if (pmap_remove_pte(pmap, 1824 ptbase + sindex, va)) 1825 break; 1826 } 1827 } 1828 1829 if (anyvalid) 1830 pmap_invalidate_all(pmap); 1831} 1832 1833/* 1834 * Routine: pmap_remove_all 1835 * Function: 1836 * Removes this physical page from 1837 * all physical maps in which it resides. 1838 * Reflects back modify bits to the pager. 1839 * 1840 * Notes: 1841 * Original versions of this routine were very 1842 * inefficient because they iteratively called 1843 * pmap_remove (slow...) 1844 */ 1845 1846static void 1847pmap_remove_all(vm_page_t m) 1848{ 1849 register pv_entry_t pv; 1850 pt_entry_t *pte, tpte; 1851 int s; 1852 1853#if defined(PMAP_DIAGNOSTIC) 1854 /* 1855 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1856 * pages! 1857 */ 1858 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1859 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1860 } 1861#endif 1862 1863 s = splvm(); 1864 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1865 pv->pv_pmap->pm_stats.resident_count--; 1866 1867 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1868 1869 tpte = atomic_readandclear_int(pte); 1870 if (tpte & PG_W) 1871 pv->pv_pmap->pm_stats.wired_count--; 1872 1873 if (tpte & PG_A) 1874 vm_page_flag_set(m, PG_REFERENCED); 1875 1876 /* 1877 * Update the vm_page_t clean and reference bits. 1878 */ 1879 if (tpte & PG_M) { 1880#if defined(PMAP_DIAGNOSTIC) 1881 if (pmap_nw_modified((pt_entry_t) tpte)) { 1882 printf( 1883 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1884 pv->pv_va, tpte); 1885 } 1886#endif 1887 if (pmap_track_modified(pv->pv_va)) 1888 vm_page_dirty(m); 1889 } 1890 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1891 1892 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1893 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1894 m->md.pv_list_count--; 1895 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1896 free_pv_entry(pv); 1897 } 1898 1899 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1900 1901 splx(s); 1902} 1903 1904/* 1905 * Set the physical protection on the 1906 * specified range of this map as requested. 1907 */ 1908void 1909pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1910{ 1911 register pt_entry_t *ptbase; 1912 vm_offset_t pdnxt; 1913 pd_entry_t ptpaddr; 1914 vm_offset_t sindex, eindex; 1915 int anychanged; 1916 1917 if (pmap == NULL) 1918 return; 1919 1920 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1921 pmap_remove(pmap, sva, eva); 1922 return; 1923 } 1924 1925 if (prot & VM_PROT_WRITE) 1926 return; 1927 1928 anychanged = 0; 1929 1930 ptbase = get_ptbase(pmap); 1931 1932 sindex = i386_btop(sva); 1933 eindex = i386_btop(eva); 1934 1935 for (; sindex < eindex; sindex = pdnxt) { 1936 1937 unsigned pdirindex; 1938 1939 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1940 1941 pdirindex = sindex / NPDEPG; 1942 ptpaddr = pmap->pm_pdir[pdirindex]; 1943 if ((ptpaddr & PG_PS) != 0) { 1944 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1945 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1946 anychanged++; 1947 continue; 1948 } 1949 1950 /* 1951 * Weed out invalid mappings. Note: we assume that the page 1952 * directory table is always allocated, and in kernel virtual. 1953 */ 1954 if (ptpaddr == 0) 1955 continue; 1956 1957 if (pdnxt > eindex) { 1958 pdnxt = eindex; 1959 } 1960 1961 for (; sindex != pdnxt; sindex++) { 1962 1963 pt_entry_t pbits; 1964 vm_page_t m; 1965 1966 pbits = ptbase[sindex]; 1967 1968 if (pbits & PG_MANAGED) { 1969 m = NULL; 1970 if (pbits & PG_A) { 1971 m = PHYS_TO_VM_PAGE(pbits); 1972 vm_page_flag_set(m, PG_REFERENCED); 1973 pbits &= ~PG_A; 1974 } 1975 if (pbits & PG_M) { 1976 if (pmap_track_modified(i386_ptob(sindex))) { 1977 if (m == NULL) 1978 m = PHYS_TO_VM_PAGE(pbits); 1979 vm_page_dirty(m); 1980 pbits &= ~PG_M; 1981 } 1982 } 1983 } 1984 1985 pbits &= ~PG_RW; 1986 1987 if (pbits != ptbase[sindex]) { 1988 ptbase[sindex] = pbits; 1989 anychanged = 1; 1990 } 1991 } 1992 } 1993 if (anychanged) 1994 pmap_invalidate_all(pmap); 1995} 1996 1997/* 1998 * Insert the given physical page (p) at 1999 * the specified virtual address (v) in the 2000 * target physical map with the protection requested. 2001 * 2002 * If specified, the page will be wired down, meaning 2003 * that the related pte can not be reclaimed. 2004 * 2005 * NB: This is the only routine which MAY NOT lazy-evaluate 2006 * or lose information. That is, this routine must actually 2007 * insert this page into the given map NOW. 2008 */ 2009void 2010pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2011 boolean_t wired) 2012{ 2013 vm_offset_t pa; 2014 register pt_entry_t *pte; 2015 vm_offset_t opa; 2016 pt_entry_t origpte, newpte; 2017 vm_page_t mpte; 2018 2019 if (pmap == NULL) 2020 return; 2021 2022 va &= PG_FRAME; 2023#ifdef PMAP_DIAGNOSTIC 2024 if (va > VM_MAX_KERNEL_ADDRESS) 2025 panic("pmap_enter: toobig"); 2026 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2027 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2028#endif 2029 2030 mpte = NULL; 2031 /* 2032 * In the case that a page table page is not 2033 * resident, we are creating it here. 2034 */ 2035 if (va < VM_MAXUSER_ADDRESS) { 2036 mpte = pmap_allocpte(pmap, va); 2037 } 2038#if 0 && defined(PMAP_DIAGNOSTIC) 2039 else { 2040 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2041 origpte = *pdeaddr; 2042 if ((origpte & PG_V) == 0) { 2043 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2044 pmap->pm_pdir[PTDPTDI], origpte, va); 2045 } 2046 } 2047#endif 2048 2049 pte = pmap_pte(pmap, va); 2050 2051 /* 2052 * Page Directory table entry not valid, we need a new PT page 2053 */ 2054 if (pte == NULL) { 2055 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2056 (void *)pmap->pm_pdir[PTDPTDI], va); 2057 } 2058 2059 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2060 origpte = *(vm_offset_t *)pte; 2061 opa = origpte & PG_FRAME; 2062 2063 if (origpte & PG_PS) 2064 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2065 2066 /* 2067 * Mapping has not changed, must be protection or wiring change. 2068 */ 2069 if (origpte && (opa == pa)) { 2070 /* 2071 * Wiring change, just update stats. We don't worry about 2072 * wiring PT pages as they remain resident as long as there 2073 * are valid mappings in them. Hence, if a user page is wired, 2074 * the PT page will be also. 2075 */ 2076 if (wired && ((origpte & PG_W) == 0)) 2077 pmap->pm_stats.wired_count++; 2078 else if (!wired && (origpte & PG_W)) 2079 pmap->pm_stats.wired_count--; 2080 2081#if defined(PMAP_DIAGNOSTIC) 2082 if (pmap_nw_modified((pt_entry_t) origpte)) { 2083 printf( 2084 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2085 va, origpte); 2086 } 2087#endif 2088 2089 /* 2090 * Remove extra pte reference 2091 */ 2092 if (mpte) 2093 mpte->hold_count--; 2094 2095 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2096 if ((origpte & PG_RW) == 0) { 2097 *pte |= PG_RW; 2098 pmap_invalidate_page(pmap, va); 2099 } 2100 return; 2101 } 2102 2103 /* 2104 * We might be turning off write access to the page, 2105 * so we go ahead and sense modify status. 2106 */ 2107 if (origpte & PG_MANAGED) { 2108 if ((origpte & PG_M) && pmap_track_modified(va)) { 2109 vm_page_t om; 2110 om = PHYS_TO_VM_PAGE(opa); 2111 vm_page_dirty(om); 2112 } 2113 pa |= PG_MANAGED; 2114 } 2115 goto validate; 2116 } 2117 /* 2118 * Mapping has changed, invalidate old range and fall through to 2119 * handle validating new mapping. 2120 */ 2121 if (opa) { 2122 int err; 2123 err = pmap_remove_pte(pmap, pte, va); 2124 if (err) 2125 panic("pmap_enter: pte vanished, va: 0x%x", va); 2126 } 2127 2128 /* 2129 * Enter on the PV list if part of our managed memory. Note that we 2130 * raise IPL while manipulating pv_table since pmap_enter can be 2131 * called at interrupt time. 2132 */ 2133 if (pmap_initialized && 2134 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2135 pmap_insert_entry(pmap, va, mpte, m); 2136 pa |= PG_MANAGED; 2137 } 2138 2139 /* 2140 * Increment counters 2141 */ 2142 pmap->pm_stats.resident_count++; 2143 if (wired) 2144 pmap->pm_stats.wired_count++; 2145 2146validate: 2147 /* 2148 * Now validate mapping with desired protection/wiring. 2149 */ 2150 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2151 2152 if (wired) 2153 newpte |= PG_W; 2154 if (va < VM_MAXUSER_ADDRESS) 2155 newpte |= PG_U; 2156 if (pmap == kernel_pmap) 2157 newpte |= pgeflag; 2158 2159 /* 2160 * if the mapping or permission bits are different, we need 2161 * to update the pte. 2162 */ 2163 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2164 *pte = newpte | PG_A; 2165 /*if (origpte)*/ { 2166 pmap_invalidate_page(pmap, va); 2167 } 2168 } 2169} 2170 2171/* 2172 * this code makes some *MAJOR* assumptions: 2173 * 1. Current pmap & pmap exists. 2174 * 2. Not wired. 2175 * 3. Read access. 2176 * 4. No page table pages. 2177 * 5. Tlbflush is deferred to calling procedure. 2178 * 6. Page IS managed. 2179 * but is *MUCH* faster than pmap_enter... 2180 */ 2181 2182static vm_page_t 2183pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2184{ 2185 pt_entry_t *pte; 2186 vm_offset_t pa; 2187 2188 /* 2189 * In the case that a page table page is not 2190 * resident, we are creating it here. 2191 */ 2192 if (va < VM_MAXUSER_ADDRESS) { 2193 unsigned ptepindex; 2194 pd_entry_t ptepa; 2195 2196 /* 2197 * Calculate pagetable page index 2198 */ 2199 ptepindex = va >> PDRSHIFT; 2200 if (mpte && (mpte->pindex == ptepindex)) { 2201 mpte->hold_count++; 2202 } else { 2203retry: 2204 /* 2205 * Get the page directory entry 2206 */ 2207 ptepa = pmap->pm_pdir[ptepindex]; 2208 2209 /* 2210 * If the page table page is mapped, we just increment 2211 * the hold count, and activate it. 2212 */ 2213 if (ptepa) { 2214 if (ptepa & PG_PS) 2215 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2216 if (pmap->pm_ptphint && 2217 (pmap->pm_ptphint->pindex == ptepindex)) { 2218 mpte = pmap->pm_ptphint; 2219 } else { 2220 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2221 pmap->pm_ptphint = mpte; 2222 } 2223 if (mpte == NULL) 2224 goto retry; 2225 mpte->hold_count++; 2226 } else { 2227 mpte = _pmap_allocpte(pmap, ptepindex); 2228 } 2229 } 2230 } else { 2231 mpte = NULL; 2232 } 2233 2234 /* 2235 * This call to vtopte makes the assumption that we are 2236 * entering the page into the current pmap. In order to support 2237 * quick entry into any pmap, one would likely use pmap_pte_quick. 2238 * But that isn't as quick as vtopte. 2239 */ 2240 pte = vtopte(va); 2241 if (*pte) { 2242 if (mpte) 2243 pmap_unwire_pte_hold(pmap, mpte); 2244 return 0; 2245 } 2246 2247 /* 2248 * Enter on the PV list if part of our managed memory. Note that we 2249 * raise IPL while manipulating pv_table since pmap_enter can be 2250 * called at interrupt time. 2251 */ 2252 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2253 pmap_insert_entry(pmap, va, mpte, m); 2254 2255 /* 2256 * Increment counters 2257 */ 2258 pmap->pm_stats.resident_count++; 2259 2260 pa = VM_PAGE_TO_PHYS(m); 2261 2262 /* 2263 * Now validate mapping with RO protection 2264 */ 2265 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2266 *pte = pa | PG_V | PG_U; 2267 else 2268 *pte = pa | PG_V | PG_U | PG_MANAGED; 2269 2270 return mpte; 2271} 2272 2273/* 2274 * Make a temporary mapping for a physical address. This is only intended 2275 * to be used for panic dumps. 2276 */ 2277void * 2278pmap_kenter_temporary(vm_offset_t pa, int i) 2279{ 2280 vm_offset_t va; 2281 2282 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE); 2283 pmap_kenter(va, pa); 2284#ifndef I386_CPU 2285 invlpg(va); 2286#else 2287 invltlb(); 2288#endif 2289 return ((void *)crashdumpmap); 2290} 2291 2292#define MAX_INIT_PT (96) 2293/* 2294 * pmap_object_init_pt preloads the ptes for a given object 2295 * into the specified pmap. This eliminates the blast of soft 2296 * faults on process startup and immediately after an mmap. 2297 */ 2298void 2299pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2300 vm_object_t object, vm_pindex_t pindex, 2301 vm_size_t size, int limit) 2302{ 2303 vm_offset_t tmpidx; 2304 int psize; 2305 vm_page_t p, mpte; 2306 int objpgs; 2307 2308 if (pmap == NULL || object == NULL) 2309 return; 2310 2311 /* 2312 * This code maps large physical mmap regions into the 2313 * processor address space. Note that some shortcuts 2314 * are taken, but the code works. 2315 */ 2316 if (pseflag && (object->type == OBJT_DEVICE) && 2317 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2318 int i; 2319 vm_page_t m[1]; 2320 unsigned int ptepindex; 2321 int npdes; 2322 pd_entry_t ptepa; 2323 2324 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2325 return; 2326 2327retry: 2328 p = vm_page_lookup(object, pindex); 2329 if (p && vm_page_sleep_busy(p, FALSE, "init4p")) 2330 goto retry; 2331 2332 if (p == NULL) { 2333 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2334 if (p == NULL) 2335 return; 2336 m[0] = p; 2337 2338 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2339 vm_page_lock_queues(); 2340 vm_page_free(p); 2341 vm_page_unlock_queues(); 2342 return; 2343 } 2344 2345 p = vm_page_lookup(object, pindex); 2346 vm_page_wakeup(p); 2347 } 2348 2349 ptepa = VM_PAGE_TO_PHYS(p); 2350 if (ptepa & (NBPDR - 1)) { 2351 return; 2352 } 2353 2354 p->valid = VM_PAGE_BITS_ALL; 2355 2356 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2357 npdes = size >> PDRSHIFT; 2358 for(i = 0; i < npdes; i++) { 2359 pmap->pm_pdir[ptepindex] = 2360 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2361 ptepa += NBPDR; 2362 ptepindex += 1; 2363 } 2364 vm_page_flag_set(p, PG_MAPPED); 2365 pmap_invalidate_all(kernel_pmap); 2366 return; 2367 } 2368 2369 psize = i386_btop(size); 2370 2371 if ((object->type != OBJT_VNODE) || 2372 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2373 (object->resident_page_count > MAX_INIT_PT))) { 2374 return; 2375 } 2376 2377 if (psize + pindex > object->size) { 2378 if (object->size < pindex) 2379 return; 2380 psize = object->size - pindex; 2381 } 2382 2383 mpte = NULL; 2384 /* 2385 * if we are processing a major portion of the object, then scan the 2386 * entire thing. 2387 */ 2388 if (psize > (object->resident_page_count >> 2)) { 2389 objpgs = psize; 2390 2391 for (p = TAILQ_FIRST(&object->memq); 2392 ((objpgs > 0) && (p != NULL)); 2393 p = TAILQ_NEXT(p, listq)) { 2394 2395 if (p->pindex < pindex || p->pindex - pindex >= psize) { 2396 continue; 2397 } 2398 tmpidx = p->pindex - pindex; 2399 /* 2400 * don't allow an madvise to blow away our really 2401 * free pages allocating pv entries. 2402 */ 2403 if ((limit & MAP_PREFAULT_MADVISE) && 2404 cnt.v_free_count < cnt.v_free_reserved) { 2405 break; 2406 } 2407 vm_page_lock_queues(); 2408 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2409 (p->busy == 0) && 2410 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2411 if ((p->queue - p->pc) == PQ_CACHE) 2412 vm_page_deactivate(p); 2413 vm_page_busy(p); 2414 vm_page_unlock_queues(); 2415 mpte = pmap_enter_quick(pmap, 2416 addr + i386_ptob(tmpidx), p, mpte); 2417 vm_page_lock_queues(); 2418 vm_page_flag_set(p, PG_MAPPED); 2419 vm_page_wakeup(p); 2420 } 2421 vm_page_unlock_queues(); 2422 objpgs -= 1; 2423 } 2424 } else { 2425 /* 2426 * else lookup the pages one-by-one. 2427 */ 2428 for (tmpidx = 0; tmpidx < psize; tmpidx += 1) { 2429 /* 2430 * don't allow an madvise to blow away our really 2431 * free pages allocating pv entries. 2432 */ 2433 if ((limit & MAP_PREFAULT_MADVISE) && 2434 cnt.v_free_count < cnt.v_free_reserved) { 2435 break; 2436 } 2437 p = vm_page_lookup(object, tmpidx + pindex); 2438 if (p == NULL) 2439 continue; 2440 vm_page_lock_queues(); 2441 if ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL && 2442 (p->busy == 0) && 2443 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2444 if ((p->queue - p->pc) == PQ_CACHE) 2445 vm_page_deactivate(p); 2446 vm_page_busy(p); 2447 vm_page_unlock_queues(); 2448 mpte = pmap_enter_quick(pmap, 2449 addr + i386_ptob(tmpidx), p, mpte); 2450 vm_page_lock_queues(); 2451 vm_page_flag_set(p, PG_MAPPED); 2452 vm_page_wakeup(p); 2453 } 2454 vm_page_unlock_queues(); 2455 } 2456 } 2457 return; 2458} 2459 2460/* 2461 * pmap_prefault provides a quick way of clustering 2462 * pagefaults into a processes address space. It is a "cousin" 2463 * of pmap_object_init_pt, except it runs at page fault time instead 2464 * of mmap time. 2465 */ 2466#define PFBAK 4 2467#define PFFOR 4 2468#define PAGEORDER_SIZE (PFBAK+PFFOR) 2469 2470static int pmap_prefault_pageorder[] = { 2471 -PAGE_SIZE, PAGE_SIZE, 2472 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2473 -3 * PAGE_SIZE, 3 * PAGE_SIZE 2474 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2475}; 2476 2477void 2478pmap_prefault(pmap, addra, entry) 2479 pmap_t pmap; 2480 vm_offset_t addra; 2481 vm_map_entry_t entry; 2482{ 2483 int i; 2484 vm_offset_t starta; 2485 vm_offset_t addr; 2486 vm_pindex_t pindex; 2487 vm_page_t m, mpte; 2488 vm_object_t object; 2489 2490 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2491 return; 2492 2493 object = entry->object.vm_object; 2494 2495 starta = addra - PFBAK * PAGE_SIZE; 2496 if (starta < entry->start) { 2497 starta = entry->start; 2498 } else if (starta > addra) { 2499 starta = 0; 2500 } 2501 2502 mpte = NULL; 2503 for (i = 0; i < PAGEORDER_SIZE; i++) { 2504 vm_object_t lobject; 2505 pt_entry_t *pte; 2506 2507 addr = addra + pmap_prefault_pageorder[i]; 2508 if (addr > addra + (PFFOR * PAGE_SIZE)) 2509 addr = 0; 2510 2511 if (addr < starta || addr >= entry->end) 2512 continue; 2513 2514 if ((*pmap_pde(pmap, addr)) == NULL) 2515 continue; 2516 2517 pte = vtopte(addr); 2518 if (*pte) 2519 continue; 2520 2521 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2522 lobject = object; 2523 for (m = vm_page_lookup(lobject, pindex); 2524 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2525 lobject = lobject->backing_object) { 2526 if (lobject->backing_object_offset & PAGE_MASK) 2527 break; 2528 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2529 m = vm_page_lookup(lobject->backing_object, pindex); 2530 } 2531 2532 /* 2533 * give-up when a page is not in memory 2534 */ 2535 if (m == NULL) 2536 break; 2537 vm_page_lock_queues(); 2538 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2539 (m->busy == 0) && 2540 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2541 2542 if ((m->queue - m->pc) == PQ_CACHE) { 2543 vm_page_deactivate(m); 2544 } 2545 vm_page_busy(m); 2546 vm_page_unlock_queues(); 2547 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2548 vm_page_lock_queues(); 2549 vm_page_flag_set(m, PG_MAPPED); 2550 vm_page_wakeup(m); 2551 } 2552 vm_page_unlock_queues(); 2553 } 2554} 2555 2556/* 2557 * Routine: pmap_change_wiring 2558 * Function: Change the wiring attribute for a map/virtual-address 2559 * pair. 2560 * In/out conditions: 2561 * The mapping must already exist in the pmap. 2562 */ 2563void 2564pmap_change_wiring(pmap, va, wired) 2565 register pmap_t pmap; 2566 vm_offset_t va; 2567 boolean_t wired; 2568{ 2569 register pt_entry_t *pte; 2570 2571 if (pmap == NULL) 2572 return; 2573 2574 pte = pmap_pte(pmap, va); 2575 2576 if (wired && !pmap_pte_w(pte)) 2577 pmap->pm_stats.wired_count++; 2578 else if (!wired && pmap_pte_w(pte)) 2579 pmap->pm_stats.wired_count--; 2580 2581 /* 2582 * Wiring is not a hardware characteristic so there is no need to 2583 * invalidate TLB. 2584 */ 2585 pmap_pte_set_w(pte, wired); 2586} 2587 2588 2589 2590/* 2591 * Copy the range specified by src_addr/len 2592 * from the source map to the range dst_addr/len 2593 * in the destination map. 2594 * 2595 * This routine is only advisory and need not do anything. 2596 */ 2597 2598void 2599pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2600 vm_offset_t src_addr) 2601{ 2602 vm_offset_t addr; 2603 vm_offset_t end_addr = src_addr + len; 2604 vm_offset_t pdnxt; 2605 pd_entry_t src_frame, dst_frame; 2606 vm_page_t m; 2607 2608 if (dst_addr != src_addr) 2609 return; 2610 2611 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2612 if (src_frame != (PTDpde & PG_FRAME)) 2613 return; 2614 2615 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2616 for (addr = src_addr; addr < end_addr; addr = pdnxt) { 2617 pt_entry_t *src_pte, *dst_pte; 2618 vm_page_t dstmpte, srcmpte; 2619 pd_entry_t srcptepaddr; 2620 unsigned ptepindex; 2621 2622 if (addr >= UPT_MIN_ADDRESS) 2623 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2624 2625 /* 2626 * Don't let optional prefaulting of pages make us go 2627 * way below the low water mark of free pages or way 2628 * above high water mark of used pv entries. 2629 */ 2630 if (cnt.v_free_count < cnt.v_free_reserved || 2631 pv_entry_count > pv_entry_high_water) 2632 break; 2633 2634 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2635 ptepindex = addr >> PDRSHIFT; 2636 2637 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2638 if (srcptepaddr == 0) 2639 continue; 2640 2641 if (srcptepaddr & PG_PS) { 2642 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2643 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2644 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2645 } 2646 continue; 2647 } 2648 2649 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2650 if ((srcmpte == NULL) || 2651 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2652 continue; 2653 2654 if (pdnxt > end_addr) 2655 pdnxt = end_addr; 2656 2657 /* 2658 * Have to recheck this before every avtopte() call below 2659 * in case we have blocked and something else used APTDpde. 2660 */ 2661 if (dst_frame != (APTDpde & PG_FRAME)) { 2662 APTDpde = dst_frame | PG_RW | PG_V; 2663 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 2664 } 2665 src_pte = vtopte(addr); 2666 dst_pte = avtopte(addr); 2667 while (addr < pdnxt) { 2668 pt_entry_t ptetemp; 2669 ptetemp = *src_pte; 2670 /* 2671 * we only virtual copy managed pages 2672 */ 2673 if ((ptetemp & PG_MANAGED) != 0) { 2674 /* 2675 * We have to check after allocpte for the 2676 * pte still being around... allocpte can 2677 * block. 2678 */ 2679 dstmpte = pmap_allocpte(dst_pmap, addr); 2680 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2681 /* 2682 * Clear the modified and 2683 * accessed (referenced) bits 2684 * during the copy. 2685 */ 2686 m = PHYS_TO_VM_PAGE(ptetemp); 2687 *dst_pte = ptetemp & ~(PG_M | PG_A); 2688 dst_pmap->pm_stats.resident_count++; 2689 pmap_insert_entry(dst_pmap, addr, 2690 dstmpte, m); 2691 } else { 2692 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2693 } 2694 if (dstmpte->hold_count >= srcmpte->hold_count) 2695 break; 2696 } 2697 addr += PAGE_SIZE; 2698 src_pte++; 2699 dst_pte++; 2700 } 2701 } 2702} 2703 2704#ifdef SMP 2705 2706/* 2707 * pmap_zpi_switchin*() 2708 * 2709 * These functions allow us to avoid doing IPIs alltogether in certain 2710 * temporary page-mapping situations (page zeroing). Instead to deal 2711 * with being preempted and moved onto a different cpu we invalidate 2712 * the page when the scheduler switches us in. This does not occur 2713 * very often so we remain relatively optimal with very little effort. 2714 */ 2715static void 2716pmap_zpi_switchin12(void) 2717{ 2718 invlpg((u_int)CADDR1); 2719 invlpg((u_int)CADDR2); 2720} 2721 2722static void 2723pmap_zpi_switchin2(void) 2724{ 2725 invlpg((u_int)CADDR2); 2726} 2727 2728static void 2729pmap_zpi_switchin3(void) 2730{ 2731 invlpg((u_int)CADDR3); 2732} 2733 2734#endif 2735 2736/* 2737 * pmap_zero_page zeros the specified hardware page by mapping 2738 * the page into KVM and using bzero to clear its contents. 2739 */ 2740void 2741pmap_zero_page(vm_page_t m) 2742{ 2743 vm_offset_t phys; 2744 2745 phys = VM_PAGE_TO_PHYS(m); 2746 if (*CMAP2) 2747 panic("pmap_zero_page: CMAP2 busy"); 2748 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2749#ifdef I386_CPU 2750 invltlb(); 2751#else 2752#ifdef SMP 2753 curthread->td_switchin = pmap_zpi_switchin2; 2754#endif 2755 invlpg((u_int)CADDR2); 2756#endif 2757#if defined(I686_CPU) 2758 if (cpu_class == CPUCLASS_686) 2759 i686_pagezero(CADDR2); 2760 else 2761#endif 2762 bzero(CADDR2, PAGE_SIZE); 2763#ifdef SMP 2764 curthread->td_switchin = NULL; 2765#endif 2766 *CMAP2 = 0; 2767} 2768 2769/* 2770 * pmap_zero_page_area zeros the specified hardware page by mapping 2771 * the page into KVM and using bzero to clear its contents. 2772 * 2773 * off and size may not cover an area beyond a single hardware page. 2774 */ 2775void 2776pmap_zero_page_area(vm_page_t m, int off, int size) 2777{ 2778 vm_offset_t phys; 2779 2780 phys = VM_PAGE_TO_PHYS(m); 2781 if (*CMAP2) 2782 panic("pmap_zero_page: CMAP2 busy"); 2783 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2784#ifdef I386_CPU 2785 invltlb(); 2786#else 2787#ifdef SMP 2788 curthread->td_switchin = pmap_zpi_switchin2; 2789#endif 2790 invlpg((u_int)CADDR2); 2791#endif 2792#if defined(I686_CPU) 2793 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2794 i686_pagezero(CADDR2); 2795 else 2796#endif 2797 bzero((char *)CADDR2 + off, size); 2798#ifdef SMP 2799 curthread->td_switchin = NULL; 2800#endif 2801 *CMAP2 = 0; 2802} 2803 2804/* 2805 * pmap_zero_page_idle zeros the specified hardware page by mapping 2806 * the page into KVM and using bzero to clear its contents. This 2807 * is intended to be called from the vm_pagezero process only and 2808 * outside of Giant. 2809 */ 2810void 2811pmap_zero_page_idle(vm_page_t m) 2812{ 2813 vm_offset_t phys; 2814 2815 phys = VM_PAGE_TO_PHYS(m); 2816 if (*CMAP3) 2817 panic("pmap_zero_page: CMAP3 busy"); 2818 *CMAP3 = PG_V | PG_RW | phys | PG_A | PG_M; 2819#ifdef I386_CPU 2820 invltlb(); 2821#else 2822#ifdef SMP 2823 curthread->td_switchin = pmap_zpi_switchin3; 2824#endif 2825 invlpg((u_int)CADDR3); 2826#endif 2827#if defined(I686_CPU) 2828 if (cpu_class == CPUCLASS_686) 2829 i686_pagezero(CADDR3); 2830 else 2831#endif 2832 bzero(CADDR3, PAGE_SIZE); 2833#ifdef SMP 2834 curthread->td_switchin = NULL; 2835#endif 2836 *CMAP3 = 0; 2837} 2838 2839/* 2840 * pmap_copy_page copies the specified (machine independent) 2841 * page by mapping the page into virtual memory and using 2842 * bcopy to copy the page, one machine dependent page at a 2843 * time. 2844 */ 2845void 2846pmap_copy_page(vm_page_t src, vm_page_t dst) 2847{ 2848 2849 if (*CMAP1) 2850 panic("pmap_copy_page: CMAP1 busy"); 2851 if (*CMAP2) 2852 panic("pmap_copy_page: CMAP2 busy"); 2853 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2854 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2855#ifdef I386_CPU 2856 invltlb(); 2857#else 2858#ifdef SMP 2859 curthread->td_switchin = pmap_zpi_switchin12; 2860#endif 2861 invlpg((u_int)CADDR1); 2862 invlpg((u_int)CADDR2); 2863#endif 2864 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2865#ifdef SMP 2866 curthread->td_switchin = NULL; 2867#endif 2868 *CMAP1 = 0; 2869 *CMAP2 = 0; 2870} 2871 2872 2873/* 2874 * Routine: pmap_pageable 2875 * Function: 2876 * Make the specified pages (by pmap, offset) 2877 * pageable (or not) as requested. 2878 * 2879 * A page which is not pageable may not take 2880 * a fault; therefore, its page table entry 2881 * must remain valid for the duration. 2882 * 2883 * This routine is merely advisory; pmap_enter 2884 * will specify that these pages are to be wired 2885 * down (or not) as appropriate. 2886 */ 2887void 2888pmap_pageable(pmap, sva, eva, pageable) 2889 pmap_t pmap; 2890 vm_offset_t sva, eva; 2891 boolean_t pageable; 2892{ 2893} 2894 2895/* 2896 * Returns true if the pmap's pv is one of the first 2897 * 16 pvs linked to from this page. This count may 2898 * be changed upwards or downwards in the future; it 2899 * is only necessary that true be returned for a small 2900 * subset of pmaps for proper page aging. 2901 */ 2902boolean_t 2903pmap_page_exists_quick(pmap, m) 2904 pmap_t pmap; 2905 vm_page_t m; 2906{ 2907 pv_entry_t pv; 2908 int loops = 0; 2909 int s; 2910 2911 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2912 return FALSE; 2913 2914 s = splvm(); 2915 2916 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2917 if (pv->pv_pmap == pmap) { 2918 splx(s); 2919 return TRUE; 2920 } 2921 loops++; 2922 if (loops >= 16) 2923 break; 2924 } 2925 splx(s); 2926 return (FALSE); 2927} 2928 2929#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2930/* 2931 * Remove all pages from specified address space 2932 * this aids process exit speeds. Also, this code 2933 * is special cased for current process only, but 2934 * can have the more generic (and slightly slower) 2935 * mode enabled. This is much faster than pmap_remove 2936 * in the case of running down an entire address space. 2937 */ 2938void 2939pmap_remove_pages(pmap, sva, eva) 2940 pmap_t pmap; 2941 vm_offset_t sva, eva; 2942{ 2943 pt_entry_t *pte, tpte; 2944 vm_page_t m; 2945 pv_entry_t pv, npv; 2946 int s; 2947 2948#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2949 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2950 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2951 return; 2952 } 2953#endif 2954 2955 s = splvm(); 2956 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2957 2958 if (pv->pv_va >= eva || pv->pv_va < sva) { 2959 npv = TAILQ_NEXT(pv, pv_plist); 2960 continue; 2961 } 2962 2963#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2964 pte = vtopte(pv->pv_va); 2965#else 2966 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2967#endif 2968 tpte = *pte; 2969 2970 if (tpte == 0) { 2971 printf("TPTE at %p IS ZERO @ VA %08x\n", 2972 pte, pv->pv_va); 2973 panic("bad pte"); 2974 } 2975 2976/* 2977 * We cannot remove wired pages from a process' mapping at this time 2978 */ 2979 if (tpte & PG_W) { 2980 npv = TAILQ_NEXT(pv, pv_plist); 2981 continue; 2982 } 2983 2984 m = PHYS_TO_VM_PAGE(tpte); 2985 KASSERT(m->phys_addr == (tpte & PG_FRAME), 2986 ("vm_page_t %p phys_addr mismatch %08x %08x", 2987 m, m->phys_addr, tpte)); 2988 2989 KASSERT(m < &vm_page_array[vm_page_array_size], 2990 ("pmap_remove_pages: bad tpte %x", tpte)); 2991 2992 pv->pv_pmap->pm_stats.resident_count--; 2993 2994 *pte = 0; 2995 2996 /* 2997 * Update the vm_page_t clean and reference bits. 2998 */ 2999 if (tpte & PG_M) { 3000 vm_page_dirty(m); 3001 } 3002 3003 npv = TAILQ_NEXT(pv, pv_plist); 3004 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 3005 3006 m->md.pv_list_count--; 3007 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3008 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 3009 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 3010 } 3011 3012 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 3013 free_pv_entry(pv); 3014 } 3015 splx(s); 3016 pmap_invalidate_all(pmap); 3017} 3018 3019/* 3020 * pmap_testbit tests bits in pte's 3021 * note that the testbit/changebit routines are inline, 3022 * and a lot of things compile-time evaluate. 3023 */ 3024static boolean_t 3025pmap_testbit(m, bit) 3026 vm_page_t m; 3027 int bit; 3028{ 3029 pv_entry_t pv; 3030 pt_entry_t *pte; 3031 int s; 3032 3033 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3034 return FALSE; 3035 3036 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 3037 return FALSE; 3038 3039 s = splvm(); 3040 3041 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3042 /* 3043 * if the bit being tested is the modified bit, then 3044 * mark clean_map and ptes as never 3045 * modified. 3046 */ 3047 if (bit & (PG_A|PG_M)) { 3048 if (!pmap_track_modified(pv->pv_va)) 3049 continue; 3050 } 3051 3052#if defined(PMAP_DIAGNOSTIC) 3053 if (!pv->pv_pmap) { 3054 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3055 continue; 3056 } 3057#endif 3058 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3059 if (*pte & bit) { 3060 splx(s); 3061 return TRUE; 3062 } 3063 } 3064 splx(s); 3065 return (FALSE); 3066} 3067 3068/* 3069 * this routine is used to modify bits in ptes 3070 */ 3071static __inline void 3072pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3073{ 3074 register pv_entry_t pv; 3075 register pt_entry_t *pte; 3076 int s; 3077 3078 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3079 return; 3080 3081 s = splvm(); 3082 3083 /* 3084 * Loop over all current mappings setting/clearing as appropos If 3085 * setting RO do we need to clear the VAC? 3086 */ 3087 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3088 /* 3089 * don't write protect pager mappings 3090 */ 3091 if (!setem && (bit == PG_RW)) { 3092 if (!pmap_track_modified(pv->pv_va)) 3093 continue; 3094 } 3095 3096#if defined(PMAP_DIAGNOSTIC) 3097 if (!pv->pv_pmap) { 3098 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3099 continue; 3100 } 3101#endif 3102 3103 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3104 3105 if (setem) { 3106 *pte |= bit; 3107 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3108 } else { 3109 pt_entry_t pbits = *pte; 3110 if (pbits & bit) { 3111 if (bit == PG_RW) { 3112 if (pbits & PG_M) { 3113 vm_page_dirty(m); 3114 } 3115 *pte = pbits & ~(PG_M|PG_RW); 3116 } else { 3117 *pte = pbits & ~bit; 3118 } 3119 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3120 } 3121 } 3122 } 3123 splx(s); 3124} 3125 3126/* 3127 * pmap_page_protect: 3128 * 3129 * Lower the permission for all mappings to a given page. 3130 */ 3131void 3132pmap_page_protect(vm_page_t m, vm_prot_t prot) 3133{ 3134 if ((prot & VM_PROT_WRITE) == 0) { 3135 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3136 pmap_changebit(m, PG_RW, FALSE); 3137 } else { 3138 pmap_remove_all(m); 3139 } 3140 } 3141} 3142 3143vm_offset_t 3144pmap_phys_address(ppn) 3145 int ppn; 3146{ 3147 return (i386_ptob(ppn)); 3148} 3149 3150/* 3151 * pmap_ts_referenced: 3152 * 3153 * Return a count of reference bits for a page, clearing those bits. 3154 * It is not necessary for every reference bit to be cleared, but it 3155 * is necessary that 0 only be returned when there are truly no 3156 * reference bits set. 3157 * 3158 * XXX: The exact number of bits to check and clear is a matter that 3159 * should be tested and standardized at some point in the future for 3160 * optimal aging of shared pages. 3161 */ 3162int 3163pmap_ts_referenced(vm_page_t m) 3164{ 3165 register pv_entry_t pv, pvf, pvn; 3166 pt_entry_t *pte; 3167 int s; 3168 int rtval = 0; 3169 3170 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3171 return (rtval); 3172 3173 s = splvm(); 3174 3175 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3176 3177 pvf = pv; 3178 3179 do { 3180 pvn = TAILQ_NEXT(pv, pv_list); 3181 3182 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3183 3184 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3185 3186 if (!pmap_track_modified(pv->pv_va)) 3187 continue; 3188 3189 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3190 3191 if (pte && (*pte & PG_A)) { 3192 *pte &= ~PG_A; 3193 3194 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3195 3196 rtval++; 3197 if (rtval > 4) { 3198 break; 3199 } 3200 } 3201 } while ((pv = pvn) != NULL && pv != pvf); 3202 } 3203 splx(s); 3204 3205 return (rtval); 3206} 3207 3208/* 3209 * pmap_is_modified: 3210 * 3211 * Return whether or not the specified physical page was modified 3212 * in any physical maps. 3213 */ 3214boolean_t 3215pmap_is_modified(vm_page_t m) 3216{ 3217 return pmap_testbit(m, PG_M); 3218} 3219 3220/* 3221 * Clear the modify bits on the specified physical page. 3222 */ 3223void 3224pmap_clear_modify(vm_page_t m) 3225{ 3226 pmap_changebit(m, PG_M, FALSE); 3227} 3228 3229/* 3230 * pmap_clear_reference: 3231 * 3232 * Clear the reference bit on the specified physical page. 3233 */ 3234void 3235pmap_clear_reference(vm_page_t m) 3236{ 3237 pmap_changebit(m, PG_A, FALSE); 3238} 3239 3240/* 3241 * Miscellaneous support routines follow 3242 */ 3243 3244static void 3245i386_protection_init() 3246{ 3247 register int *kp, prot; 3248 3249 kp = protection_codes; 3250 for (prot = 0; prot < 8; prot++) { 3251 switch (prot) { 3252 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3253 /* 3254 * Read access is also 0. There isn't any execute bit, 3255 * so just make it readable. 3256 */ 3257 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3258 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3259 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3260 *kp++ = 0; 3261 break; 3262 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3263 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3264 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3265 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3266 *kp++ = PG_RW; 3267 break; 3268 } 3269 } 3270} 3271 3272/* 3273 * Map a set of physical memory pages into the kernel virtual 3274 * address space. Return a pointer to where it is mapped. This 3275 * routine is intended to be used for mapping device memory, 3276 * NOT real memory. 3277 */ 3278void * 3279pmap_mapdev(pa, size) 3280 vm_offset_t pa; 3281 vm_size_t size; 3282{ 3283 vm_offset_t va, tmpva, offset; 3284 3285 offset = pa & PAGE_MASK; 3286 size = round_page(offset + size); 3287 pa = trunc_page(pa); 3288 3289 /* We have a 1MB direct mapped region at KERNBASE */ 3290 if (pa < 0x00100000 && pa + size <= 0x00100000) 3291 return (void *)(pa + KERNBASE); 3292 3293 GIANT_REQUIRED; 3294 va = kmem_alloc_pageable(kernel_map, size); 3295 if (!va) 3296 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3297 3298 for (tmpva = va; size > 0; ) { 3299 pmap_kenter(tmpva, pa); 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 = round_page(offset + size); 3319 if (base >= KERNBASE && va + size <= KERNBASE + 0x00100000) 3320 return; /* direct mapped */ 3321 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE) { 3322 pte = vtopte(tmpva); 3323 *pte = 0; 3324 } 3325 pmap_invalidate_range(kernel_pmap, va, tmpva); 3326 kmem_free(kernel_map, base, size); 3327} 3328 3329/* 3330 * perform the pmap work for mincore 3331 */ 3332int 3333pmap_mincore(pmap, addr) 3334 pmap_t pmap; 3335 vm_offset_t addr; 3336{ 3337 pt_entry_t *ptep, pte; 3338 vm_page_t m; 3339 int val = 0; 3340 3341 ptep = pmap_pte(pmap, addr); 3342 if (ptep == 0) { 3343 return 0; 3344 } 3345 3346 if ((pte = *ptep) != 0) { 3347 vm_offset_t pa; 3348 3349 val = MINCORE_INCORE; 3350 if ((pte & PG_MANAGED) == 0) 3351 return val; 3352 3353 pa = pte & PG_FRAME; 3354 3355 m = PHYS_TO_VM_PAGE(pa); 3356 3357 /* 3358 * Modified by us 3359 */ 3360 if (pte & PG_M) 3361 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3362 /* 3363 * Modified by someone 3364 */ 3365 else if (m->dirty || pmap_is_modified(m)) 3366 val |= MINCORE_MODIFIED_OTHER; 3367 /* 3368 * Referenced by us 3369 */ 3370 if (pte & PG_A) 3371 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3372 3373 /* 3374 * Referenced by someone 3375 */ 3376 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3377 val |= MINCORE_REFERENCED_OTHER; 3378 vm_page_flag_set(m, PG_REFERENCED); 3379 } 3380 } 3381 return val; 3382} 3383 3384void 3385pmap_activate(struct thread *td) 3386{ 3387 struct proc *p = td->td_proc; 3388 pmap_t pmap; 3389 u_int32_t cr3; 3390 3391 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3392#if defined(SMP) 3393 pmap->pm_active |= PCPU_GET(cpumask); 3394#else 3395 pmap->pm_active |= 1; 3396#endif 3397 cr3 = vtophys(pmap->pm_pdir); 3398 /* XXXKSE this is wrong. 3399 * pmap_activate is for the current thread on the current cpu 3400 */ 3401 if (p->p_flag & P_KSES) { 3402 /* Make sure all other cr3 entries are updated. */ 3403 /* what if they are running? XXXKSE (maybe abort them) */ 3404 FOREACH_THREAD_IN_PROC(p, td) { 3405 td->td_pcb->pcb_cr3 = cr3; 3406 } 3407 } else { 3408 td->td_pcb->pcb_cr3 = cr3; 3409 } 3410 load_cr3(cr3); 3411#ifdef SWTCH_OPTIM_STATS 3412 tlb_flush_count++; 3413#endif 3414} 3415 3416vm_offset_t 3417pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3418{ 3419 3420 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3421 return addr; 3422 } 3423 3424 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3425 return addr; 3426} 3427 3428 3429#if defined(PMAP_DEBUG) 3430pmap_pid_dump(int pid) 3431{ 3432 pmap_t pmap; 3433 struct proc *p; 3434 int npte = 0; 3435 int index; 3436 3437 sx_slock(&allproc_lock); 3438 LIST_FOREACH(p, &allproc, p_list) { 3439 if (p->p_pid != pid) 3440 continue; 3441 3442 if (p->p_vmspace) { 3443 int i,j; 3444 index = 0; 3445 pmap = vmspace_pmap(p->p_vmspace); 3446 for (i = 0; i < NPDEPG; i++) { 3447 pd_entry_t *pde; 3448 pt_entry_t *pte; 3449 vm_offset_t base = i << PDRSHIFT; 3450 3451 pde = &pmap->pm_pdir[i]; 3452 if (pde && pmap_pde_v(pde)) { 3453 for (j = 0; j < NPTEPG; j++) { 3454 vm_offset_t va = base + (j << PAGE_SHIFT); 3455 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3456 if (index) { 3457 index = 0; 3458 printf("\n"); 3459 } 3460 sx_sunlock(&allproc_lock); 3461 return npte; 3462 } 3463 pte = pmap_pte_quick(pmap, va); 3464 if (pte && pmap_pte_v(pte)) { 3465 pt_entry_t pa; 3466 vm_page_t m; 3467 pa = *pte; 3468 m = PHYS_TO_VM_PAGE(pa); 3469 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3470 va, pa, m->hold_count, m->wire_count, m->flags); 3471 npte++; 3472 index++; 3473 if (index >= 2) { 3474 index = 0; 3475 printf("\n"); 3476 } else { 3477 printf(" "); 3478 } 3479 } 3480 } 3481 } 3482 } 3483 } 3484 } 3485 sx_sunlock(&allproc_lock); 3486 return npte; 3487} 3488#endif 3489 3490#if defined(DEBUG) 3491 3492static void pads(pmap_t pm); 3493void pmap_pvdump(vm_offset_t pa); 3494 3495/* print address space of pmap*/ 3496static void 3497pads(pm) 3498 pmap_t pm; 3499{ 3500 int i, j; 3501 vm_offset_t va; 3502 pt_entry_t *ptep; 3503 3504 if (pm == kernel_pmap) 3505 return; 3506 for (i = 0; i < NPDEPG; i++) 3507 if (pm->pm_pdir[i]) 3508 for (j = 0; j < NPTEPG; j++) { 3509 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3510 if (pm == kernel_pmap && va < KERNBASE) 3511 continue; 3512 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3513 continue; 3514 ptep = pmap_pte_quick(pm, va); 3515 if (pmap_pte_v(ptep)) 3516 printf("%x:%x ", va, *ptep); 3517 }; 3518 3519} 3520 3521void 3522pmap_pvdump(pa) 3523 vm_offset_t pa; 3524{ 3525 pv_entry_t pv; 3526 vm_page_t m; 3527 3528 printf("pa %x", pa); 3529 m = PHYS_TO_VM_PAGE(pa); 3530 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3531 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3532 pads(pv->pv_pmap); 3533 } 3534 printf(" "); 3535} 3536#endif 3537