pmap.c revision 102241
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 102241 2002-08-21 23:39:52Z archie $ 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 != NULL) { 929 vm_page_lock_queues(); 930 if (vm_page_sleep_if_busy(m, FALSE, "pplookp")) 931 goto retry; 932 vm_page_unlock_queues(); 933 } 934 return m; 935} 936 937/* 938 * Create the kernel stack (including pcb for i386) for a new thread. 939 * This routine directly affects the fork perf for a process and 940 * create performance for a thread. 941 */ 942void 943pmap_new_thread(struct thread *td) 944{ 945 int i; 946 vm_page_t ma[KSTACK_PAGES]; 947 vm_object_t ksobj; 948 vm_page_t m; 949 vm_offset_t ks; 950 951 /* 952 * allocate object for the kstack 953 */ 954 ksobj = vm_object_allocate(OBJT_DEFAULT, KSTACK_PAGES); 955 td->td_kstack_obj = ksobj; 956 957 /* get a kernel virtual address for the kstack for this thread */ 958#ifdef KSTACK_GUARD 959 ks = kmem_alloc_nofault(kernel_map, (KSTACK_PAGES + 1) * PAGE_SIZE); 960 if (ks == 0) 961 panic("pmap_new_thread: kstack allocation failed"); 962 if (*vtopte(ks) != 0) 963 pmap_qremove(ks, 1); 964 ks += PAGE_SIZE; 965 td->td_kstack = ks; 966#else 967 /* get a kernel virtual address for the kstack for this thread */ 968 ks = kmem_alloc_nofault(kernel_map, KSTACK_PAGES * PAGE_SIZE); 969 if (ks == 0) 970 panic("pmap_new_thread: kstack allocation failed"); 971 td->td_kstack = ks; 972#endif 973 /* 974 * For the length of the stack, link in a real page of ram for each 975 * page of stack. 976 */ 977 for (i = 0; i < KSTACK_PAGES; i++) { 978 /* 979 * Get a kernel stack page 980 */ 981 m = vm_page_grab(ksobj, i, 982 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED); 983 ma[i] = m; 984 985 vm_page_wakeup(m); 986 vm_page_flag_clear(m, PG_ZERO); 987 m->valid = VM_PAGE_BITS_ALL; 988 } 989 pmap_qenter(ks, ma, KSTACK_PAGES); 990} 991 992/* 993 * Dispose the kernel stack for a thread that has exited. 994 * This routine directly impacts the exit perf of a process and thread. 995 */ 996void 997pmap_dispose_thread(td) 998 struct thread *td; 999{ 1000 int i; 1001 vm_object_t ksobj; 1002 vm_offset_t ks; 1003 vm_page_t m; 1004 1005 ksobj = td->td_kstack_obj; 1006 ks = td->td_kstack; 1007 pmap_qremove(ks, KSTACK_PAGES); 1008 for (i = 0; i < KSTACK_PAGES; i++) { 1009 m = vm_page_lookup(ksobj, i); 1010 if (m == NULL) 1011 panic("pmap_dispose_thread: kstack already missing?"); 1012 vm_page_lock_queues(); 1013 vm_page_busy(m); 1014 vm_page_unwire(m, 0); 1015 vm_page_free(m); 1016 vm_page_unlock_queues(); 1017 } 1018 /* 1019 * Free the space that this stack was mapped to in the kernel 1020 * address map. 1021 */ 1022#ifdef KSTACK_GUARD 1023 kmem_free(kernel_map, ks - PAGE_SIZE, (KSTACK_PAGES + 1) * PAGE_SIZE); 1024#else 1025 kmem_free(kernel_map, ks, KSTACK_PAGES * PAGE_SIZE); 1026#endif 1027 vm_object_deallocate(ksobj); 1028} 1029 1030/* 1031 * Allow the Kernel stack for a thread to be prejudicially paged out. 1032 */ 1033void 1034pmap_swapout_thread(td) 1035 struct thread *td; 1036{ 1037 int i; 1038 vm_object_t ksobj; 1039 vm_offset_t ks; 1040 vm_page_t m; 1041 1042 ksobj = td->td_kstack_obj; 1043 ks = td->td_kstack; 1044 pmap_qremove(ks, KSTACK_PAGES); 1045 for (i = 0; i < KSTACK_PAGES; i++) { 1046 m = vm_page_lookup(ksobj, i); 1047 if (m == NULL) 1048 panic("pmap_swapout_thread: kstack already missing?"); 1049 vm_page_lock_queues(); 1050 vm_page_dirty(m); 1051 vm_page_unwire(m, 0); 1052 vm_page_unlock_queues(); 1053 } 1054} 1055 1056/* 1057 * Bring the kernel stack for a specified thread back in. 1058 */ 1059void 1060pmap_swapin_thread(td) 1061 struct thread *td; 1062{ 1063 int i, rv; 1064 vm_page_t ma[KSTACK_PAGES]; 1065 vm_object_t ksobj; 1066 vm_offset_t ks; 1067 vm_page_t m; 1068 1069 ksobj = td->td_kstack_obj; 1070 ks = td->td_kstack; 1071 for (i = 0; i < KSTACK_PAGES; i++) { 1072 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1073 if (m->valid != VM_PAGE_BITS_ALL) { 1074 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1075 if (rv != VM_PAGER_OK) 1076 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1077 m = vm_page_lookup(ksobj, i); 1078 m->valid = VM_PAGE_BITS_ALL; 1079 } 1080 ma[i] = m; 1081 vm_page_lock_queues(); 1082 vm_page_wire(m); 1083 vm_page_wakeup(m); 1084 vm_page_unlock_queues(); 1085 } 1086 pmap_qenter(ks, ma, KSTACK_PAGES); 1087} 1088 1089/*************************************************** 1090 * Page table page management routines..... 1091 ***************************************************/ 1092 1093/* 1094 * This routine unholds page table pages, and if the hold count 1095 * drops to zero, then it decrements the wire count. 1096 */ 1097static int 1098_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1099{ 1100 1101 while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) 1102 ; 1103 1104 if (m->hold_count == 0) { 1105 vm_offset_t pteva; 1106 /* 1107 * unmap the page table page 1108 */ 1109 pmap->pm_pdir[m->pindex] = 0; 1110 --pmap->pm_stats.resident_count; 1111 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1112 (PTDpde & PG_FRAME)) { 1113 /* 1114 * Do a invltlb to make the invalidated mapping 1115 * take effect immediately. 1116 */ 1117 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); 1118 pmap_invalidate_page(pmap, pteva); 1119 } 1120 1121 if (pmap->pm_ptphint == m) 1122 pmap->pm_ptphint = NULL; 1123 1124 /* 1125 * If the page is finally unwired, simply free it. 1126 */ 1127 --m->wire_count; 1128 if (m->wire_count == 0) { 1129 vm_page_busy(m); 1130 vm_page_free_zero(m); 1131 --cnt.v_wire_count; 1132 } 1133 return 1; 1134 } 1135 return 0; 1136} 1137 1138static PMAP_INLINE int 1139pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1140{ 1141 vm_page_unhold(m); 1142 if (m->hold_count == 0) 1143 return _pmap_unwire_pte_hold(pmap, m); 1144 else 1145 return 0; 1146} 1147 1148/* 1149 * After removing a page table entry, this routine is used to 1150 * conditionally free the page, and manage the hold/wire counts. 1151 */ 1152static int 1153pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1154{ 1155 unsigned ptepindex; 1156 if (va >= VM_MAXUSER_ADDRESS) 1157 return 0; 1158 1159 if (mpte == NULL) { 1160 ptepindex = (va >> PDRSHIFT); 1161 if (pmap->pm_ptphint && 1162 (pmap->pm_ptphint->pindex == ptepindex)) { 1163 mpte = pmap->pm_ptphint; 1164 } else { 1165 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1166 pmap->pm_ptphint = mpte; 1167 } 1168 } 1169 1170 return pmap_unwire_pte_hold(pmap, mpte); 1171} 1172 1173void 1174pmap_pinit0(pmap) 1175 struct pmap *pmap; 1176{ 1177 pmap->pm_pdir = 1178 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1179 pmap_kenter((vm_offset_t)pmap->pm_pdir, (vm_offset_t)IdlePTD); 1180#ifndef I386_CPU 1181 invlpg((vm_offset_t)pmap->pm_pdir); 1182#else 1183 invltlb(); 1184#endif 1185 pmap->pm_ptphint = NULL; 1186 pmap->pm_active = 0; 1187 TAILQ_INIT(&pmap->pm_pvlist); 1188 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1189 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1190} 1191 1192/* 1193 * Initialize a preallocated and zeroed pmap structure, 1194 * such as one in a vmspace structure. 1195 */ 1196void 1197pmap_pinit(pmap) 1198 register struct pmap *pmap; 1199{ 1200 vm_page_t ptdpg; 1201 1202 /* 1203 * No need to allocate page table space yet but we do need a valid 1204 * page directory table. 1205 */ 1206 if (pmap->pm_pdir == NULL) 1207 pmap->pm_pdir = 1208 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1209 1210 /* 1211 * allocate object for the ptes 1212 */ 1213 if (pmap->pm_pteobj == NULL) 1214 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1215 1216 /* 1217 * allocate the page directory page 1218 */ 1219 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1220 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED | VM_ALLOC_ZERO); 1221 vm_page_flag_clear(ptdpg, PG_BUSY); 1222 ptdpg->valid = VM_PAGE_BITS_ALL; 1223 1224 pmap_qenter((vm_offset_t) pmap->pm_pdir, &ptdpg, 1); 1225 if ((ptdpg->flags & PG_ZERO) == 0) 1226 bzero(pmap->pm_pdir, PAGE_SIZE); 1227 1228 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1229 /* Wire in kernel global address entries. */ 1230 /* XXX copies current process, does not fill in MPPTDI */ 1231 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1232#ifdef SMP 1233 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1234#endif 1235 1236 /* install self-referential address mapping entry */ 1237 pmap->pm_pdir[PTDPTDI] = 1238 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1239 1240 pmap->pm_active = 0; 1241 pmap->pm_ptphint = NULL; 1242 TAILQ_INIT(&pmap->pm_pvlist); 1243 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1244} 1245 1246/* 1247 * Wire in kernel global address entries. To avoid a race condition 1248 * between pmap initialization and pmap_growkernel, this procedure 1249 * should be called after the vmspace is attached to the process 1250 * but before this pmap is activated. 1251 */ 1252void 1253pmap_pinit2(pmap) 1254 struct pmap *pmap; 1255{ 1256 /* XXX: Remove this stub when no longer called */ 1257} 1258 1259static int 1260pmap_release_free_page(pmap_t pmap, vm_page_t p) 1261{ 1262 pd_entry_t *pde = pmap->pm_pdir; 1263 1264 /* 1265 * This code optimizes the case of freeing non-busy 1266 * page-table pages. Those pages are zero now, and 1267 * might as well be placed directly into the zero queue. 1268 */ 1269 vm_page_lock_queues(); 1270 if (vm_page_sleep_if_busy(p, FALSE, "pmaprl")) 1271 return (0); 1272 vm_page_busy(p); 1273 1274 /* 1275 * Remove the page table page from the processes address space. 1276 */ 1277 pde[p->pindex] = 0; 1278 pmap->pm_stats.resident_count--; 1279 1280 if (p->hold_count) { 1281 panic("pmap_release: freeing held page table page"); 1282 } 1283 /* 1284 * Page directory pages need to have the kernel 1285 * stuff cleared, so they can go into the zero queue also. 1286 */ 1287 if (p->pindex == PTDPTDI) { 1288 bzero(pde + KPTDI, nkpt * PTESIZE); 1289#ifdef SMP 1290 pde[MPPTDI] = 0; 1291#endif 1292 pde[APTDPTDI] = 0; 1293 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1294 } 1295 1296 if (pmap->pm_ptphint == p) 1297 pmap->pm_ptphint = NULL; 1298 1299 p->wire_count--; 1300 cnt.v_wire_count--; 1301 vm_page_free_zero(p); 1302 vm_page_unlock_queues(); 1303 return 1; 1304} 1305 1306/* 1307 * this routine is called if the page table page is not 1308 * mapped correctly. 1309 */ 1310static vm_page_t 1311_pmap_allocpte(pmap, ptepindex) 1312 pmap_t pmap; 1313 unsigned ptepindex; 1314{ 1315 vm_offset_t pteva, ptepa; /* XXXPA */ 1316 vm_page_t m; 1317 1318 /* 1319 * Find or fabricate a new pagetable page 1320 */ 1321 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1322 VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1323 1324 KASSERT(m->queue == PQ_NONE, 1325 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1326 1327 /* 1328 * Increment the hold count for the page table page 1329 * (denoting a new mapping.) 1330 */ 1331 m->hold_count++; 1332 1333 /* 1334 * Map the pagetable page into the process address space, if 1335 * it isn't already there. 1336 */ 1337 1338 pmap->pm_stats.resident_count++; 1339 1340 ptepa = VM_PAGE_TO_PHYS(m); 1341 pmap->pm_pdir[ptepindex] = 1342 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1343 1344 /* 1345 * Set the page table hint 1346 */ 1347 pmap->pm_ptphint = m; 1348 1349 /* 1350 * Try to use the new mapping, but if we cannot, then 1351 * do it with the routine that maps the page explicitly. 1352 */ 1353 if ((m->flags & PG_ZERO) == 0) { 1354 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1355 (PTDpde & PG_FRAME)) { 1356 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1357 bzero((caddr_t) pteva, PAGE_SIZE); 1358 } else { 1359 pmap_zero_page(m); 1360 } 1361 } 1362 1363 m->valid = VM_PAGE_BITS_ALL; 1364 vm_page_flag_clear(m, PG_ZERO); 1365 vm_page_wakeup(m); 1366 1367 return m; 1368} 1369 1370static vm_page_t 1371pmap_allocpte(pmap_t pmap, vm_offset_t va) 1372{ 1373 unsigned ptepindex; 1374 pd_entry_t ptepa; 1375 vm_page_t m; 1376 1377 /* 1378 * Calculate pagetable page index 1379 */ 1380 ptepindex = va >> PDRSHIFT; 1381 1382 /* 1383 * Get the page directory entry 1384 */ 1385 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1386 1387 /* 1388 * This supports switching from a 4MB page to a 1389 * normal 4K page. 1390 */ 1391 if (ptepa & PG_PS) { 1392 pmap->pm_pdir[ptepindex] = 0; 1393 ptepa = 0; 1394 pmap_invalidate_all(kernel_pmap); 1395 } 1396 1397 /* 1398 * If the page table page is mapped, we just increment the 1399 * hold count, and activate it. 1400 */ 1401 if (ptepa) { 1402 /* 1403 * In order to get the page table page, try the 1404 * hint first. 1405 */ 1406 if (pmap->pm_ptphint && 1407 (pmap->pm_ptphint->pindex == ptepindex)) { 1408 m = pmap->pm_ptphint; 1409 } else { 1410 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1411 pmap->pm_ptphint = m; 1412 } 1413 m->hold_count++; 1414 return m; 1415 } 1416 /* 1417 * Here if the pte page isn't mapped, or if it has been deallocated. 1418 */ 1419 return _pmap_allocpte(pmap, ptepindex); 1420} 1421 1422 1423/*************************************************** 1424* Pmap allocation/deallocation routines. 1425 ***************************************************/ 1426 1427/* 1428 * Release any resources held by the given physical map. 1429 * Called when a pmap initialized by pmap_pinit is being released. 1430 * Should only be called if the map contains no valid mappings. 1431 */ 1432void 1433pmap_release(pmap_t pmap) 1434{ 1435 vm_page_t p,n,ptdpg; 1436 vm_object_t object = pmap->pm_pteobj; 1437 int curgeneration; 1438 1439#if defined(DIAGNOSTIC) 1440 if (object->ref_count != 1) 1441 panic("pmap_release: pteobj reference count != 1"); 1442#endif 1443 1444 ptdpg = NULL; 1445 LIST_REMOVE(pmap, pm_list); 1446retry: 1447 curgeneration = object->generation; 1448 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1449 n = TAILQ_NEXT(p, listq); 1450 if (p->pindex == PTDPTDI) { 1451 ptdpg = p; 1452 continue; 1453 } 1454 while (1) { 1455 if (!pmap_release_free_page(pmap, p) && 1456 (object->generation != curgeneration)) 1457 goto retry; 1458 } 1459 } 1460 1461 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1462 goto retry; 1463} 1464 1465static int 1466kvm_size(SYSCTL_HANDLER_ARGS) 1467{ 1468 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1469 1470 return sysctl_handle_long(oidp, &ksize, 0, req); 1471} 1472SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1473 0, 0, kvm_size, "IU", "Size of KVM"); 1474 1475static int 1476kvm_free(SYSCTL_HANDLER_ARGS) 1477{ 1478 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1479 1480 return sysctl_handle_long(oidp, &kfree, 0, req); 1481} 1482SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1483 0, 0, kvm_free, "IU", "Amount of KVM free"); 1484 1485/* 1486 * grow the number of kernel page table entries, if needed 1487 */ 1488void 1489pmap_growkernel(vm_offset_t addr) 1490{ 1491 struct pmap *pmap; 1492 int s; 1493 vm_offset_t ptppaddr; 1494 vm_page_t nkpg; 1495 pd_entry_t newpdir; 1496 1497 s = splhigh(); 1498 if (kernel_vm_end == 0) { 1499 kernel_vm_end = KERNBASE; 1500 nkpt = 0; 1501 while (pdir_pde(PTD, kernel_vm_end)) { 1502 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1503 nkpt++; 1504 } 1505 } 1506 addr = roundup2(addr, PAGE_SIZE * NPTEPG); 1507 while (kernel_vm_end < addr) { 1508 if (pdir_pde(PTD, kernel_vm_end)) { 1509 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1510 continue; 1511 } 1512 1513 /* 1514 * This index is bogus, but out of the way 1515 */ 1516 nkpg = vm_page_alloc(kptobj, nkpt, 1517 VM_ALLOC_SYSTEM | VM_ALLOC_WIRED); 1518 if (!nkpg) 1519 panic("pmap_growkernel: no memory to grow kernel"); 1520 1521 nkpt++; 1522 1523 pmap_zero_page(nkpg); 1524 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1525 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1526 pdir_pde(PTD, kernel_vm_end) = newpdir; 1527 1528 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1529 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1530 } 1531 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1532 } 1533 splx(s); 1534} 1535 1536 1537/*************************************************** 1538 * page management routines. 1539 ***************************************************/ 1540 1541/* 1542 * free the pv_entry back to the free list 1543 */ 1544static PMAP_INLINE void 1545free_pv_entry(pv_entry_t pv) 1546{ 1547 pv_entry_count--; 1548 uma_zfree(pvzone, pv); 1549} 1550 1551/* 1552 * get a new pv_entry, allocating a block from the system 1553 * when needed. 1554 * the memory allocation is performed bypassing the malloc code 1555 * because of the possibility of allocations at interrupt time. 1556 */ 1557static pv_entry_t 1558get_pv_entry(void) 1559{ 1560 pv_entry_count++; 1561 if (pv_entry_high_water && 1562 (pv_entry_count > pv_entry_high_water) && 1563 (pmap_pagedaemon_waken == 0)) { 1564 pmap_pagedaemon_waken = 1; 1565 wakeup (&vm_pages_needed); 1566 } 1567 return uma_zalloc(pvzone, M_NOWAIT); 1568} 1569 1570/* 1571 * This routine is very drastic, but can save the system 1572 * in a pinch. 1573 */ 1574void 1575pmap_collect() 1576{ 1577 int i; 1578 vm_page_t m; 1579 static int warningdone = 0; 1580 1581 if (pmap_pagedaemon_waken == 0) 1582 return; 1583 1584 if (warningdone < 5) { 1585 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1586 warningdone++; 1587 } 1588 1589 for(i = 0; i < vm_page_array_size; i++) { 1590 m = &vm_page_array[i]; 1591 if (m->wire_count || m->hold_count || m->busy || 1592 (m->flags & (PG_BUSY | PG_UNMANAGED))) 1593 continue; 1594 pmap_remove_all(m); 1595 } 1596 pmap_pagedaemon_waken = 0; 1597} 1598 1599 1600/* 1601 * If it is the first entry on the list, it is actually 1602 * in the header and we must copy the following entry up 1603 * to the header. Otherwise we must search the list for 1604 * the entry. In either case we free the now unused entry. 1605 */ 1606 1607static int 1608pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1609{ 1610 pv_entry_t pv; 1611 int rtval; 1612 int s; 1613 1614 s = splvm(); 1615 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1616 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1617 if (pmap == pv->pv_pmap && va == pv->pv_va) 1618 break; 1619 } 1620 } else { 1621 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1622 if (va == pv->pv_va) 1623 break; 1624 } 1625 } 1626 1627 rtval = 0; 1628 if (pv) { 1629 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1630 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1631 m->md.pv_list_count--; 1632 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1633 vm_page_flag_clear(m, PG_WRITEABLE); 1634 1635 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1636 free_pv_entry(pv); 1637 } 1638 1639 splx(s); 1640 return rtval; 1641} 1642 1643/* 1644 * Create a pv entry for page at pa for 1645 * (pmap, va). 1646 */ 1647static void 1648pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1649{ 1650 1651 int s; 1652 pv_entry_t pv; 1653 1654 s = splvm(); 1655 pv = get_pv_entry(); 1656 pv->pv_va = va; 1657 pv->pv_pmap = pmap; 1658 pv->pv_ptem = mpte; 1659 1660 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1661 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1662 m->md.pv_list_count++; 1663 1664 splx(s); 1665} 1666 1667/* 1668 * pmap_remove_pte: do the things to unmap a page in a process 1669 */ 1670static int 1671pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1672{ 1673 pt_entry_t oldpte; 1674 vm_page_t m; 1675 1676 oldpte = atomic_readandclear_int(ptq); 1677 if (oldpte & PG_W) 1678 pmap->pm_stats.wired_count -= 1; 1679 /* 1680 * Machines that don't support invlpg, also don't support 1681 * PG_G. 1682 */ 1683 if (oldpte & PG_G) 1684 pmap_invalidate_page(kernel_pmap, va); 1685 pmap->pm_stats.resident_count -= 1; 1686 if (oldpte & PG_MANAGED) { 1687 m = PHYS_TO_VM_PAGE(oldpte); 1688 if (oldpte & PG_M) { 1689#if defined(PMAP_DIAGNOSTIC) 1690 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1691 printf( 1692 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1693 va, oldpte); 1694 } 1695#endif 1696 if (pmap_track_modified(va)) 1697 vm_page_dirty(m); 1698 } 1699 if (oldpte & PG_A) 1700 vm_page_flag_set(m, PG_REFERENCED); 1701 return pmap_remove_entry(pmap, m, va); 1702 } else { 1703 return pmap_unuse_pt(pmap, va, NULL); 1704 } 1705 1706 return 0; 1707} 1708 1709/* 1710 * Remove a single page from a process address space 1711 */ 1712static void 1713pmap_remove_page(pmap_t pmap, vm_offset_t va) 1714{ 1715 register pt_entry_t *ptq; 1716 1717 /* 1718 * if there is no pte for this address, just skip it!!! 1719 */ 1720 if (*pmap_pde(pmap, va) == 0) { 1721 return; 1722 } 1723 1724 /* 1725 * get a local va for mappings for this pmap. 1726 */ 1727 ptq = get_ptbase(pmap) + i386_btop(va); 1728 if (*ptq) { 1729 (void) pmap_remove_pte(pmap, ptq, va); 1730 pmap_invalidate_page(pmap, va); 1731 } 1732 return; 1733} 1734 1735/* 1736 * Remove the given range of addresses from the specified map. 1737 * 1738 * It is assumed that the start and end are properly 1739 * rounded to the page size. 1740 */ 1741void 1742pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1743{ 1744 register pt_entry_t *ptbase; 1745 vm_offset_t pdnxt; 1746 pd_entry_t ptpaddr; 1747 vm_offset_t sindex, eindex; 1748 int anyvalid; 1749 1750 if (pmap == NULL) 1751 return; 1752 1753 if (pmap->pm_stats.resident_count == 0) 1754 return; 1755 1756 /* 1757 * special handling of removing one page. a very 1758 * common operation and easy to short circuit some 1759 * code. 1760 */ 1761 if ((sva + PAGE_SIZE == eva) && 1762 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1763 pmap_remove_page(pmap, sva); 1764 return; 1765 } 1766 1767 anyvalid = 0; 1768 1769 /* 1770 * Get a local virtual address for the mappings that are being 1771 * worked with. 1772 */ 1773 ptbase = get_ptbase(pmap); 1774 1775 sindex = i386_btop(sva); 1776 eindex = i386_btop(eva); 1777 1778 for (; sindex < eindex; sindex = pdnxt) { 1779 unsigned pdirindex; 1780 1781 /* 1782 * Calculate index for next page table. 1783 */ 1784 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1785 if (pmap->pm_stats.resident_count == 0) 1786 break; 1787 1788 pdirindex = sindex / NPDEPG; 1789 ptpaddr = pmap->pm_pdir[pdirindex]; 1790 if ((ptpaddr & PG_PS) != 0) { 1791 pmap->pm_pdir[pdirindex] = 0; 1792 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1793 anyvalid++; 1794 continue; 1795 } 1796 1797 /* 1798 * Weed out invalid mappings. Note: we assume that the page 1799 * directory table is always allocated, and in kernel virtual. 1800 */ 1801 if (ptpaddr == 0) 1802 continue; 1803 1804 /* 1805 * Limit our scan to either the end of the va represented 1806 * by the current page table page, or to the end of the 1807 * range being removed. 1808 */ 1809 if (pdnxt > eindex) { 1810 pdnxt = eindex; 1811 } 1812 1813 for (; sindex != pdnxt; sindex++) { 1814 vm_offset_t va; 1815 if (ptbase[sindex] == 0) { 1816 continue; 1817 } 1818 va = i386_ptob(sindex); 1819 1820 anyvalid++; 1821 if (pmap_remove_pte(pmap, 1822 ptbase + sindex, va)) 1823 break; 1824 } 1825 } 1826 1827 if (anyvalid) 1828 pmap_invalidate_all(pmap); 1829} 1830 1831/* 1832 * Routine: pmap_remove_all 1833 * Function: 1834 * Removes this physical page from 1835 * all physical maps in which it resides. 1836 * Reflects back modify bits to the pager. 1837 * 1838 * Notes: 1839 * Original versions of this routine were very 1840 * inefficient because they iteratively called 1841 * pmap_remove (slow...) 1842 */ 1843 1844static void 1845pmap_remove_all(vm_page_t m) 1846{ 1847 register pv_entry_t pv; 1848 pt_entry_t *pte, tpte; 1849 int s; 1850 1851#if defined(PMAP_DIAGNOSTIC) 1852 /* 1853 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1854 * pages! 1855 */ 1856 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1857 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1858 } 1859#endif 1860 1861 s = splvm(); 1862 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1863 pv->pv_pmap->pm_stats.resident_count--; 1864 1865 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1866 1867 tpte = atomic_readandclear_int(pte); 1868 if (tpte & PG_W) 1869 pv->pv_pmap->pm_stats.wired_count--; 1870 1871 if (tpte & PG_A) 1872 vm_page_flag_set(m, PG_REFERENCED); 1873 1874 /* 1875 * Update the vm_page_t clean and reference bits. 1876 */ 1877 if (tpte & PG_M) { 1878#if defined(PMAP_DIAGNOSTIC) 1879 if (pmap_nw_modified((pt_entry_t) tpte)) { 1880 printf( 1881 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1882 pv->pv_va, tpte); 1883 } 1884#endif 1885 if (pmap_track_modified(pv->pv_va)) 1886 vm_page_dirty(m); 1887 } 1888 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1889 1890 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1891 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1892 m->md.pv_list_count--; 1893 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1894 free_pv_entry(pv); 1895 } 1896 1897 vm_page_flag_clear(m, PG_WRITEABLE); 1898 1899 splx(s); 1900} 1901 1902/* 1903 * Set the physical protection on the 1904 * specified range of this map as requested. 1905 */ 1906void 1907pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1908{ 1909 register pt_entry_t *ptbase; 1910 vm_offset_t pdnxt; 1911 pd_entry_t ptpaddr; 1912 vm_offset_t sindex, eindex; 1913 int anychanged; 1914 1915 if (pmap == NULL) 1916 return; 1917 1918 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1919 pmap_remove(pmap, sva, eva); 1920 return; 1921 } 1922 1923 if (prot & VM_PROT_WRITE) 1924 return; 1925 1926 anychanged = 0; 1927 1928 ptbase = get_ptbase(pmap); 1929 1930 sindex = i386_btop(sva); 1931 eindex = i386_btop(eva); 1932 1933 for (; sindex < eindex; sindex = pdnxt) { 1934 1935 unsigned pdirindex; 1936 1937 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1938 1939 pdirindex = sindex / NPDEPG; 1940 ptpaddr = pmap->pm_pdir[pdirindex]; 1941 if ((ptpaddr & PG_PS) != 0) { 1942 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1943 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1944 anychanged++; 1945 continue; 1946 } 1947 1948 /* 1949 * Weed out invalid mappings. Note: we assume that the page 1950 * directory table is always allocated, and in kernel virtual. 1951 */ 1952 if (ptpaddr == 0) 1953 continue; 1954 1955 if (pdnxt > eindex) { 1956 pdnxt = eindex; 1957 } 1958 1959 for (; sindex != pdnxt; sindex++) { 1960 1961 pt_entry_t pbits; 1962 vm_page_t m; 1963 1964 pbits = ptbase[sindex]; 1965 1966 if (pbits & PG_MANAGED) { 1967 m = NULL; 1968 if (pbits & PG_A) { 1969 m = PHYS_TO_VM_PAGE(pbits); 1970 vm_page_flag_set(m, PG_REFERENCED); 1971 pbits &= ~PG_A; 1972 } 1973 if (pbits & PG_M) { 1974 if (pmap_track_modified(i386_ptob(sindex))) { 1975 if (m == NULL) 1976 m = PHYS_TO_VM_PAGE(pbits); 1977 vm_page_dirty(m); 1978 pbits &= ~PG_M; 1979 } 1980 } 1981 } 1982 1983 pbits &= ~PG_RW; 1984 1985 if (pbits != ptbase[sindex]) { 1986 ptbase[sindex] = pbits; 1987 anychanged = 1; 1988 } 1989 } 1990 } 1991 if (anychanged) 1992 pmap_invalidate_all(pmap); 1993} 1994 1995/* 1996 * Insert the given physical page (p) at 1997 * the specified virtual address (v) in the 1998 * target physical map with the protection requested. 1999 * 2000 * If specified, the page will be wired down, meaning 2001 * that the related pte can not be reclaimed. 2002 * 2003 * NB: This is the only routine which MAY NOT lazy-evaluate 2004 * or lose information. That is, this routine must actually 2005 * insert this page into the given map NOW. 2006 */ 2007void 2008pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2009 boolean_t wired) 2010{ 2011 vm_offset_t pa; 2012 register pt_entry_t *pte; 2013 vm_offset_t opa; 2014 pt_entry_t origpte, newpte; 2015 vm_page_t mpte; 2016 2017 if (pmap == NULL) 2018 return; 2019 2020 va &= PG_FRAME; 2021#ifdef PMAP_DIAGNOSTIC 2022 if (va > VM_MAX_KERNEL_ADDRESS) 2023 panic("pmap_enter: toobig"); 2024 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2025 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2026#endif 2027 2028 mpte = NULL; 2029 /* 2030 * In the case that a page table page is not 2031 * resident, we are creating it here. 2032 */ 2033 if (va < VM_MAXUSER_ADDRESS) { 2034 mpte = pmap_allocpte(pmap, va); 2035 } 2036#if 0 && defined(PMAP_DIAGNOSTIC) 2037 else { 2038 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2039 origpte = *pdeaddr; 2040 if ((origpte & PG_V) == 0) { 2041 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2042 pmap->pm_pdir[PTDPTDI], origpte, va); 2043 } 2044 } 2045#endif 2046 2047 pte = pmap_pte(pmap, va); 2048 2049 /* 2050 * Page Directory table entry not valid, we need a new PT page 2051 */ 2052 if (pte == NULL) { 2053 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2054 (void *)pmap->pm_pdir[PTDPTDI], va); 2055 } 2056 2057 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2058 origpte = *(vm_offset_t *)pte; 2059 opa = origpte & PG_FRAME; 2060 2061 if (origpte & PG_PS) 2062 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2063 2064 /* 2065 * Mapping has not changed, must be protection or wiring change. 2066 */ 2067 if (origpte && (opa == pa)) { 2068 /* 2069 * Wiring change, just update stats. We don't worry about 2070 * wiring PT pages as they remain resident as long as there 2071 * are valid mappings in them. Hence, if a user page is wired, 2072 * the PT page will be also. 2073 */ 2074 if (wired && ((origpte & PG_W) == 0)) 2075 pmap->pm_stats.wired_count++; 2076 else if (!wired && (origpte & PG_W)) 2077 pmap->pm_stats.wired_count--; 2078 2079#if defined(PMAP_DIAGNOSTIC) 2080 if (pmap_nw_modified((pt_entry_t) origpte)) { 2081 printf( 2082 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2083 va, origpte); 2084 } 2085#endif 2086 2087 /* 2088 * Remove extra pte reference 2089 */ 2090 if (mpte) 2091 mpte->hold_count--; 2092 2093 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2094 if ((origpte & PG_RW) == 0) { 2095 *pte |= PG_RW; 2096 pmap_invalidate_page(pmap, va); 2097 } 2098 return; 2099 } 2100 2101 /* 2102 * We might be turning off write access to the page, 2103 * so we go ahead and sense modify status. 2104 */ 2105 if (origpte & PG_MANAGED) { 2106 if ((origpte & PG_M) && pmap_track_modified(va)) { 2107 vm_page_t om; 2108 om = PHYS_TO_VM_PAGE(opa); 2109 vm_page_dirty(om); 2110 } 2111 pa |= PG_MANAGED; 2112 } 2113 goto validate; 2114 } 2115 /* 2116 * Mapping has changed, invalidate old range and fall through to 2117 * handle validating new mapping. 2118 */ 2119 if (opa) { 2120 int err; 2121 err = pmap_remove_pte(pmap, pte, va); 2122 if (err) 2123 panic("pmap_enter: pte vanished, va: 0x%x", va); 2124 } 2125 2126 /* 2127 * Enter on the PV list if part of our managed memory. Note that we 2128 * raise IPL while manipulating pv_table since pmap_enter can be 2129 * called at interrupt time. 2130 */ 2131 if (pmap_initialized && 2132 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2133 pmap_insert_entry(pmap, va, mpte, m); 2134 pa |= PG_MANAGED; 2135 } 2136 2137 /* 2138 * Increment counters 2139 */ 2140 pmap->pm_stats.resident_count++; 2141 if (wired) 2142 pmap->pm_stats.wired_count++; 2143 2144validate: 2145 /* 2146 * Now validate mapping with desired protection/wiring. 2147 */ 2148 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2149 2150 if (wired) 2151 newpte |= PG_W; 2152 if (va < VM_MAXUSER_ADDRESS) 2153 newpte |= PG_U; 2154 if (pmap == kernel_pmap) 2155 newpte |= pgeflag; 2156 2157 /* 2158 * if the mapping or permission bits are different, we need 2159 * to update the pte. 2160 */ 2161 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2162 *pte = newpte | PG_A; 2163 /*if (origpte)*/ { 2164 pmap_invalidate_page(pmap, va); 2165 } 2166 } 2167} 2168 2169/* 2170 * this code makes some *MAJOR* assumptions: 2171 * 1. Current pmap & pmap exists. 2172 * 2. Not wired. 2173 * 3. Read access. 2174 * 4. No page table pages. 2175 * 5. Tlbflush is deferred to calling procedure. 2176 * 6. Page IS managed. 2177 * but is *MUCH* faster than pmap_enter... 2178 */ 2179 2180static vm_page_t 2181pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2182{ 2183 pt_entry_t *pte; 2184 vm_offset_t pa; 2185 2186 /* 2187 * In the case that a page table page is not 2188 * resident, we are creating it here. 2189 */ 2190 if (va < VM_MAXUSER_ADDRESS) { 2191 unsigned ptepindex; 2192 pd_entry_t ptepa; 2193 2194 /* 2195 * Calculate pagetable page index 2196 */ 2197 ptepindex = va >> PDRSHIFT; 2198 if (mpte && (mpte->pindex == ptepindex)) { 2199 mpte->hold_count++; 2200 } else { 2201retry: 2202 /* 2203 * Get the page directory entry 2204 */ 2205 ptepa = pmap->pm_pdir[ptepindex]; 2206 2207 /* 2208 * If the page table page is mapped, we just increment 2209 * the hold count, and activate it. 2210 */ 2211 if (ptepa) { 2212 if (ptepa & PG_PS) 2213 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2214 if (pmap->pm_ptphint && 2215 (pmap->pm_ptphint->pindex == ptepindex)) { 2216 mpte = pmap->pm_ptphint; 2217 } else { 2218 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2219 pmap->pm_ptphint = mpte; 2220 } 2221 if (mpte == NULL) 2222 goto retry; 2223 mpte->hold_count++; 2224 } else { 2225 mpte = _pmap_allocpte(pmap, ptepindex); 2226 } 2227 } 2228 } else { 2229 mpte = NULL; 2230 } 2231 2232 /* 2233 * This call to vtopte makes the assumption that we are 2234 * entering the page into the current pmap. In order to support 2235 * quick entry into any pmap, one would likely use pmap_pte_quick. 2236 * But that isn't as quick as vtopte. 2237 */ 2238 pte = vtopte(va); 2239 if (*pte) { 2240 if (mpte) 2241 pmap_unwire_pte_hold(pmap, mpte); 2242 return 0; 2243 } 2244 2245 /* 2246 * Enter on the PV list if part of our managed memory. Note that we 2247 * raise IPL while manipulating pv_table since pmap_enter can be 2248 * called at interrupt time. 2249 */ 2250 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2251 pmap_insert_entry(pmap, va, mpte, m); 2252 2253 /* 2254 * Increment counters 2255 */ 2256 pmap->pm_stats.resident_count++; 2257 2258 pa = VM_PAGE_TO_PHYS(m); 2259 2260 /* 2261 * Now validate mapping with RO protection 2262 */ 2263 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2264 *pte = pa | PG_V | PG_U; 2265 else 2266 *pte = pa | PG_V | PG_U | PG_MANAGED; 2267 2268 return mpte; 2269} 2270 2271/* 2272 * Make a temporary mapping for a physical address. This is only intended 2273 * to be used for panic dumps. 2274 */ 2275void * 2276pmap_kenter_temporary(vm_offset_t pa, int i) 2277{ 2278 vm_offset_t va; 2279 2280 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE); 2281 pmap_kenter(va, pa); 2282#ifndef I386_CPU 2283 invlpg(va); 2284#else 2285 invltlb(); 2286#endif 2287 return ((void *)crashdumpmap); 2288} 2289 2290#define MAX_INIT_PT (96) 2291/* 2292 * pmap_object_init_pt preloads the ptes for a given object 2293 * into the specified pmap. This eliminates the blast of soft 2294 * faults on process startup and immediately after an mmap. 2295 */ 2296void 2297pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2298 vm_object_t object, vm_pindex_t pindex, 2299 vm_size_t size, int limit) 2300{ 2301 vm_offset_t tmpidx; 2302 int psize; 2303 vm_page_t p, mpte; 2304 int objpgs; 2305 2306 if (pmap == NULL || object == NULL) 2307 return; 2308 2309 /* 2310 * This code maps large physical mmap regions into the 2311 * processor address space. Note that some shortcuts 2312 * are taken, but the code works. 2313 */ 2314 if (pseflag && (object->type == OBJT_DEVICE) && 2315 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2316 int i; 2317 vm_page_t m[1]; 2318 unsigned int ptepindex; 2319 int npdes; 2320 pd_entry_t ptepa; 2321 2322 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2323 return; 2324 2325retry: 2326 p = vm_page_lookup(object, pindex); 2327 if (p != NULL) { 2328 vm_page_lock_queues(); 2329 if (vm_page_sleep_if_busy(p, FALSE, "init4p")) 2330 goto retry; 2331 vm_page_unlock_queues(); 2332 } else { 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 pmap_invalidate_all(kernel_pmap); 2365 return; 2366 } 2367 2368 psize = i386_btop(size); 2369 2370 if ((object->type != OBJT_VNODE) || 2371 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2372 (object->resident_page_count > MAX_INIT_PT))) { 2373 return; 2374 } 2375 2376 if (psize + pindex > object->size) { 2377 if (object->size < pindex) 2378 return; 2379 psize = object->size - pindex; 2380 } 2381 2382 mpte = NULL; 2383 /* 2384 * if we are processing a major portion of the object, then scan the 2385 * entire thing. 2386 */ 2387 if (psize > (object->resident_page_count >> 2)) { 2388 objpgs = psize; 2389 2390 for (p = TAILQ_FIRST(&object->memq); 2391 ((objpgs > 0) && (p != NULL)); 2392 p = TAILQ_NEXT(p, listq)) { 2393 2394 if (p->pindex < pindex || p->pindex - pindex >= psize) { 2395 continue; 2396 } 2397 tmpidx = p->pindex - pindex; 2398 /* 2399 * don't allow an madvise to blow away our really 2400 * free pages allocating pv entries. 2401 */ 2402 if ((limit & MAP_PREFAULT_MADVISE) && 2403 cnt.v_free_count < cnt.v_free_reserved) { 2404 break; 2405 } 2406 vm_page_lock_queues(); 2407 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2408 (p->busy == 0) && 2409 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2410 if ((p->queue - p->pc) == PQ_CACHE) 2411 vm_page_deactivate(p); 2412 vm_page_busy(p); 2413 vm_page_unlock_queues(); 2414 mpte = pmap_enter_quick(pmap, 2415 addr + i386_ptob(tmpidx), p, mpte); 2416 vm_page_lock_queues(); 2417 vm_page_wakeup(p); 2418 } 2419 vm_page_unlock_queues(); 2420 objpgs -= 1; 2421 } 2422 } else { 2423 /* 2424 * else lookup the pages one-by-one. 2425 */ 2426 for (tmpidx = 0; tmpidx < psize; tmpidx += 1) { 2427 /* 2428 * don't allow an madvise to blow away our really 2429 * free pages allocating pv entries. 2430 */ 2431 if ((limit & MAP_PREFAULT_MADVISE) && 2432 cnt.v_free_count < cnt.v_free_reserved) { 2433 break; 2434 } 2435 p = vm_page_lookup(object, tmpidx + pindex); 2436 if (p == NULL) 2437 continue; 2438 vm_page_lock_queues(); 2439 if ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL && 2440 (p->busy == 0) && 2441 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2442 if ((p->queue - p->pc) == PQ_CACHE) 2443 vm_page_deactivate(p); 2444 vm_page_busy(p); 2445 vm_page_unlock_queues(); 2446 mpte = pmap_enter_quick(pmap, 2447 addr + i386_ptob(tmpidx), p, mpte); 2448 vm_page_lock_queues(); 2449 vm_page_wakeup(p); 2450 } 2451 vm_page_unlock_queues(); 2452 } 2453 } 2454 return; 2455} 2456 2457/* 2458 * pmap_prefault provides a quick way of clustering 2459 * pagefaults into a processes address space. It is a "cousin" 2460 * of pmap_object_init_pt, except it runs at page fault time instead 2461 * of mmap time. 2462 */ 2463#define PFBAK 4 2464#define PFFOR 4 2465#define PAGEORDER_SIZE (PFBAK+PFFOR) 2466 2467static int pmap_prefault_pageorder[] = { 2468 -PAGE_SIZE, PAGE_SIZE, 2469 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2470 -3 * PAGE_SIZE, 3 * PAGE_SIZE 2471 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2472}; 2473 2474void 2475pmap_prefault(pmap, addra, entry) 2476 pmap_t pmap; 2477 vm_offset_t addra; 2478 vm_map_entry_t entry; 2479{ 2480 int i; 2481 vm_offset_t starta; 2482 vm_offset_t addr; 2483 vm_pindex_t pindex; 2484 vm_page_t m, mpte; 2485 vm_object_t object; 2486 2487 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2488 return; 2489 2490 object = entry->object.vm_object; 2491 2492 starta = addra - PFBAK * PAGE_SIZE; 2493 if (starta < entry->start) { 2494 starta = entry->start; 2495 } else if (starta > addra) { 2496 starta = 0; 2497 } 2498 2499 mpte = NULL; 2500 for (i = 0; i < PAGEORDER_SIZE; i++) { 2501 vm_object_t lobject; 2502 pt_entry_t *pte; 2503 2504 addr = addra + pmap_prefault_pageorder[i]; 2505 if (addr > addra + (PFFOR * PAGE_SIZE)) 2506 addr = 0; 2507 2508 if (addr < starta || addr >= entry->end) 2509 continue; 2510 2511 if ((*pmap_pde(pmap, addr)) == 0) 2512 continue; 2513 2514 pte = vtopte(addr); 2515 if (*pte) 2516 continue; 2517 2518 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2519 lobject = object; 2520 for (m = vm_page_lookup(lobject, pindex); 2521 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2522 lobject = lobject->backing_object) { 2523 if (lobject->backing_object_offset & PAGE_MASK) 2524 break; 2525 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2526 m = vm_page_lookup(lobject->backing_object, pindex); 2527 } 2528 2529 /* 2530 * give-up when a page is not in memory 2531 */ 2532 if (m == NULL) 2533 break; 2534 vm_page_lock_queues(); 2535 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2536 (m->busy == 0) && 2537 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2538 2539 if ((m->queue - m->pc) == PQ_CACHE) { 2540 vm_page_deactivate(m); 2541 } 2542 vm_page_busy(m); 2543 vm_page_unlock_queues(); 2544 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2545 vm_page_lock_queues(); 2546 vm_page_wakeup(m); 2547 } 2548 vm_page_unlock_queues(); 2549 } 2550} 2551 2552/* 2553 * Routine: pmap_change_wiring 2554 * Function: Change the wiring attribute for a map/virtual-address 2555 * pair. 2556 * In/out conditions: 2557 * The mapping must already exist in the pmap. 2558 */ 2559void 2560pmap_change_wiring(pmap, va, wired) 2561 register pmap_t pmap; 2562 vm_offset_t va; 2563 boolean_t wired; 2564{ 2565 register pt_entry_t *pte; 2566 2567 if (pmap == NULL) 2568 return; 2569 2570 pte = pmap_pte(pmap, va); 2571 2572 if (wired && !pmap_pte_w(pte)) 2573 pmap->pm_stats.wired_count++; 2574 else if (!wired && pmap_pte_w(pte)) 2575 pmap->pm_stats.wired_count--; 2576 2577 /* 2578 * Wiring is not a hardware characteristic so there is no need to 2579 * invalidate TLB. 2580 */ 2581 pmap_pte_set_w(pte, wired); 2582} 2583 2584 2585 2586/* 2587 * Copy the range specified by src_addr/len 2588 * from the source map to the range dst_addr/len 2589 * in the destination map. 2590 * 2591 * This routine is only advisory and need not do anything. 2592 */ 2593 2594void 2595pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2596 vm_offset_t src_addr) 2597{ 2598 vm_offset_t addr; 2599 vm_offset_t end_addr = src_addr + len; 2600 vm_offset_t pdnxt; 2601 pd_entry_t src_frame, dst_frame; 2602 vm_page_t m; 2603 2604 if (dst_addr != src_addr) 2605 return; 2606 2607 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2608 if (src_frame != (PTDpde & PG_FRAME)) 2609 return; 2610 2611 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2612 for (addr = src_addr; addr < end_addr; addr = pdnxt) { 2613 pt_entry_t *src_pte, *dst_pte; 2614 vm_page_t dstmpte, srcmpte; 2615 pd_entry_t srcptepaddr; 2616 unsigned ptepindex; 2617 2618 if (addr >= UPT_MIN_ADDRESS) 2619 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2620 2621 /* 2622 * Don't let optional prefaulting of pages make us go 2623 * way below the low water mark of free pages or way 2624 * above high water mark of used pv entries. 2625 */ 2626 if (cnt.v_free_count < cnt.v_free_reserved || 2627 pv_entry_count > pv_entry_high_water) 2628 break; 2629 2630 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2631 ptepindex = addr >> PDRSHIFT; 2632 2633 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2634 if (srcptepaddr == 0) 2635 continue; 2636 2637 if (srcptepaddr & PG_PS) { 2638 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2639 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2640 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2641 } 2642 continue; 2643 } 2644 2645 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2646 if ((srcmpte == NULL) || 2647 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2648 continue; 2649 2650 if (pdnxt > end_addr) 2651 pdnxt = end_addr; 2652 2653 /* 2654 * Have to recheck this before every avtopte() call below 2655 * in case we have blocked and something else used APTDpde. 2656 */ 2657 if (dst_frame != (APTDpde & PG_FRAME)) { 2658 APTDpde = dst_frame | PG_RW | PG_V; 2659 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 2660 } 2661 src_pte = vtopte(addr); 2662 dst_pte = avtopte(addr); 2663 while (addr < pdnxt) { 2664 pt_entry_t ptetemp; 2665 ptetemp = *src_pte; 2666 /* 2667 * we only virtual copy managed pages 2668 */ 2669 if ((ptetemp & PG_MANAGED) != 0) { 2670 /* 2671 * We have to check after allocpte for the 2672 * pte still being around... allocpte can 2673 * block. 2674 */ 2675 dstmpte = pmap_allocpte(dst_pmap, addr); 2676 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2677 /* 2678 * Clear the modified and 2679 * accessed (referenced) bits 2680 * during the copy. 2681 */ 2682 m = PHYS_TO_VM_PAGE(ptetemp); 2683 *dst_pte = ptetemp & ~(PG_M | PG_A); 2684 dst_pmap->pm_stats.resident_count++; 2685 pmap_insert_entry(dst_pmap, addr, 2686 dstmpte, m); 2687 } else { 2688 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2689 } 2690 if (dstmpte->hold_count >= srcmpte->hold_count) 2691 break; 2692 } 2693 addr += PAGE_SIZE; 2694 src_pte++; 2695 dst_pte++; 2696 } 2697 } 2698} 2699 2700#ifdef SMP 2701 2702/* 2703 * pmap_zpi_switchin*() 2704 * 2705 * These functions allow us to avoid doing IPIs alltogether in certain 2706 * temporary page-mapping situations (page zeroing). Instead to deal 2707 * with being preempted and moved onto a different cpu we invalidate 2708 * the page when the scheduler switches us in. This does not occur 2709 * very often so we remain relatively optimal with very little effort. 2710 */ 2711static void 2712pmap_zpi_switchin12(void) 2713{ 2714 invlpg((u_int)CADDR1); 2715 invlpg((u_int)CADDR2); 2716} 2717 2718static void 2719pmap_zpi_switchin2(void) 2720{ 2721 invlpg((u_int)CADDR2); 2722} 2723 2724static void 2725pmap_zpi_switchin3(void) 2726{ 2727 invlpg((u_int)CADDR3); 2728} 2729 2730#endif 2731 2732/* 2733 * pmap_zero_page zeros the specified hardware page by mapping 2734 * the page into KVM and using bzero to clear its contents. 2735 */ 2736void 2737pmap_zero_page(vm_page_t m) 2738{ 2739 vm_offset_t phys; 2740 2741 phys = VM_PAGE_TO_PHYS(m); 2742 if (*CMAP2) 2743 panic("pmap_zero_page: CMAP2 busy"); 2744 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2745#ifdef I386_CPU 2746 invltlb(); 2747#else 2748#ifdef SMP 2749 curthread->td_switchin = pmap_zpi_switchin2; 2750#endif 2751 invlpg((u_int)CADDR2); 2752#endif 2753#if defined(I686_CPU) 2754 if (cpu_class == CPUCLASS_686) 2755 i686_pagezero(CADDR2); 2756 else 2757#endif 2758 bzero(CADDR2, PAGE_SIZE); 2759#ifdef SMP 2760 curthread->td_switchin = NULL; 2761#endif 2762 *CMAP2 = 0; 2763} 2764 2765/* 2766 * pmap_zero_page_area zeros the specified hardware page by mapping 2767 * the page into KVM and using bzero to clear its contents. 2768 * 2769 * off and size may not cover an area beyond a single hardware page. 2770 */ 2771void 2772pmap_zero_page_area(vm_page_t m, int off, int size) 2773{ 2774 vm_offset_t phys; 2775 2776 phys = VM_PAGE_TO_PHYS(m); 2777 if (*CMAP2) 2778 panic("pmap_zero_page: CMAP2 busy"); 2779 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2780#ifdef I386_CPU 2781 invltlb(); 2782#else 2783#ifdef SMP 2784 curthread->td_switchin = pmap_zpi_switchin2; 2785#endif 2786 invlpg((u_int)CADDR2); 2787#endif 2788#if defined(I686_CPU) 2789 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2790 i686_pagezero(CADDR2); 2791 else 2792#endif 2793 bzero((char *)CADDR2 + off, size); 2794#ifdef SMP 2795 curthread->td_switchin = NULL; 2796#endif 2797 *CMAP2 = 0; 2798} 2799 2800/* 2801 * pmap_zero_page_idle zeros the specified hardware page by mapping 2802 * the page into KVM and using bzero to clear its contents. This 2803 * is intended to be called from the vm_pagezero process only and 2804 * outside of Giant. 2805 */ 2806void 2807pmap_zero_page_idle(vm_page_t m) 2808{ 2809 vm_offset_t phys; 2810 2811 phys = VM_PAGE_TO_PHYS(m); 2812 if (*CMAP3) 2813 panic("pmap_zero_page: CMAP3 busy"); 2814 *CMAP3 = PG_V | PG_RW | phys | PG_A | PG_M; 2815#ifdef I386_CPU 2816 invltlb(); 2817#else 2818#ifdef SMP 2819 curthread->td_switchin = pmap_zpi_switchin3; 2820#endif 2821 invlpg((u_int)CADDR3); 2822#endif 2823#if defined(I686_CPU) 2824 if (cpu_class == CPUCLASS_686) 2825 i686_pagezero(CADDR3); 2826 else 2827#endif 2828 bzero(CADDR3, PAGE_SIZE); 2829#ifdef SMP 2830 curthread->td_switchin = NULL; 2831#endif 2832 *CMAP3 = 0; 2833} 2834 2835/* 2836 * pmap_copy_page copies the specified (machine independent) 2837 * page by mapping the page into virtual memory and using 2838 * bcopy to copy the page, one machine dependent page at a 2839 * time. 2840 */ 2841void 2842pmap_copy_page(vm_page_t src, vm_page_t dst) 2843{ 2844 2845 if (*CMAP1) 2846 panic("pmap_copy_page: CMAP1 busy"); 2847 if (*CMAP2) 2848 panic("pmap_copy_page: CMAP2 busy"); 2849 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2850 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2851#ifdef I386_CPU 2852 invltlb(); 2853#else 2854#ifdef SMP 2855 curthread->td_switchin = pmap_zpi_switchin12; 2856#endif 2857 invlpg((u_int)CADDR1); 2858 invlpg((u_int)CADDR2); 2859#endif 2860 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2861#ifdef SMP 2862 curthread->td_switchin = NULL; 2863#endif 2864 *CMAP1 = 0; 2865 *CMAP2 = 0; 2866} 2867 2868 2869/* 2870 * Routine: pmap_pageable 2871 * Function: 2872 * Make the specified pages (by pmap, offset) 2873 * pageable (or not) as requested. 2874 * 2875 * A page which is not pageable may not take 2876 * a fault; therefore, its page table entry 2877 * must remain valid for the duration. 2878 * 2879 * This routine is merely advisory; pmap_enter 2880 * will specify that these pages are to be wired 2881 * down (or not) as appropriate. 2882 */ 2883void 2884pmap_pageable(pmap, sva, eva, pageable) 2885 pmap_t pmap; 2886 vm_offset_t sva, eva; 2887 boolean_t pageable; 2888{ 2889} 2890 2891/* 2892 * Returns true if the pmap's pv is one of the first 2893 * 16 pvs linked to from this page. This count may 2894 * be changed upwards or downwards in the future; it 2895 * is only necessary that true be returned for a small 2896 * subset of pmaps for proper page aging. 2897 */ 2898boolean_t 2899pmap_page_exists_quick(pmap, m) 2900 pmap_t pmap; 2901 vm_page_t m; 2902{ 2903 pv_entry_t pv; 2904 int loops = 0; 2905 int s; 2906 2907 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2908 return FALSE; 2909 2910 s = splvm(); 2911 2912 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2913 if (pv->pv_pmap == pmap) { 2914 splx(s); 2915 return TRUE; 2916 } 2917 loops++; 2918 if (loops >= 16) 2919 break; 2920 } 2921 splx(s); 2922 return (FALSE); 2923} 2924 2925#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2926/* 2927 * Remove all pages from specified address space 2928 * this aids process exit speeds. Also, this code 2929 * is special cased for current process only, but 2930 * can have the more generic (and slightly slower) 2931 * mode enabled. This is much faster than pmap_remove 2932 * in the case of running down an entire address space. 2933 */ 2934void 2935pmap_remove_pages(pmap, sva, eva) 2936 pmap_t pmap; 2937 vm_offset_t sva, eva; 2938{ 2939 pt_entry_t *pte, tpte; 2940 vm_page_t m; 2941 pv_entry_t pv, npv; 2942 int s; 2943 2944#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2945 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2946 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2947 return; 2948 } 2949#endif 2950 2951 s = splvm(); 2952 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2953 2954 if (pv->pv_va >= eva || pv->pv_va < sva) { 2955 npv = TAILQ_NEXT(pv, pv_plist); 2956 continue; 2957 } 2958 2959#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2960 pte = vtopte(pv->pv_va); 2961#else 2962 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2963#endif 2964 tpte = *pte; 2965 2966 if (tpte == 0) { 2967 printf("TPTE at %p IS ZERO @ VA %08x\n", 2968 pte, pv->pv_va); 2969 panic("bad pte"); 2970 } 2971 2972/* 2973 * We cannot remove wired pages from a process' mapping at this time 2974 */ 2975 if (tpte & PG_W) { 2976 npv = TAILQ_NEXT(pv, pv_plist); 2977 continue; 2978 } 2979 2980 m = PHYS_TO_VM_PAGE(tpte); 2981 KASSERT(m->phys_addr == (tpte & PG_FRAME), 2982 ("vm_page_t %p phys_addr mismatch %08x %08x", 2983 m, m->phys_addr, tpte)); 2984 2985 KASSERT(m < &vm_page_array[vm_page_array_size], 2986 ("pmap_remove_pages: bad tpte %x", tpte)); 2987 2988 pv->pv_pmap->pm_stats.resident_count--; 2989 2990 *pte = 0; 2991 2992 /* 2993 * Update the vm_page_t clean and reference bits. 2994 */ 2995 if (tpte & PG_M) { 2996 vm_page_dirty(m); 2997 } 2998 2999 npv = TAILQ_NEXT(pv, pv_plist); 3000 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 3001 3002 m->md.pv_list_count--; 3003 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3004 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 3005 vm_page_flag_clear(m, PG_WRITEABLE); 3006 } 3007 3008 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 3009 free_pv_entry(pv); 3010 } 3011 splx(s); 3012 pmap_invalidate_all(pmap); 3013} 3014 3015/* 3016 * pmap_testbit tests bits in pte's 3017 * note that the testbit/changebit routines are inline, 3018 * and a lot of things compile-time evaluate. 3019 */ 3020static boolean_t 3021pmap_testbit(m, bit) 3022 vm_page_t m; 3023 int bit; 3024{ 3025 pv_entry_t pv; 3026 pt_entry_t *pte; 3027 int s; 3028 3029 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3030 return FALSE; 3031 3032 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 3033 return FALSE; 3034 3035 s = splvm(); 3036 3037 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3038 /* 3039 * if the bit being tested is the modified bit, then 3040 * mark clean_map and ptes as never 3041 * modified. 3042 */ 3043 if (bit & (PG_A|PG_M)) { 3044 if (!pmap_track_modified(pv->pv_va)) 3045 continue; 3046 } 3047 3048#if defined(PMAP_DIAGNOSTIC) 3049 if (!pv->pv_pmap) { 3050 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3051 continue; 3052 } 3053#endif 3054 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3055 if (*pte & bit) { 3056 splx(s); 3057 return TRUE; 3058 } 3059 } 3060 splx(s); 3061 return (FALSE); 3062} 3063 3064/* 3065 * this routine is used to modify bits in ptes 3066 */ 3067static __inline void 3068pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3069{ 3070 register pv_entry_t pv; 3071 register pt_entry_t *pte; 3072 int s; 3073 3074 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3075 return; 3076 3077 s = splvm(); 3078 3079 /* 3080 * Loop over all current mappings setting/clearing as appropos If 3081 * setting RO do we need to clear the VAC? 3082 */ 3083 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3084 /* 3085 * don't write protect pager mappings 3086 */ 3087 if (!setem && (bit == PG_RW)) { 3088 if (!pmap_track_modified(pv->pv_va)) 3089 continue; 3090 } 3091 3092#if defined(PMAP_DIAGNOSTIC) 3093 if (!pv->pv_pmap) { 3094 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3095 continue; 3096 } 3097#endif 3098 3099 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3100 3101 if (setem) { 3102 *pte |= bit; 3103 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3104 } else { 3105 pt_entry_t pbits = *pte; 3106 if (pbits & bit) { 3107 if (bit == PG_RW) { 3108 if (pbits & PG_M) { 3109 vm_page_dirty(m); 3110 } 3111 *pte = pbits & ~(PG_M|PG_RW); 3112 } else { 3113 *pte = pbits & ~bit; 3114 } 3115 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3116 } 3117 } 3118 } 3119 splx(s); 3120} 3121 3122/* 3123 * pmap_page_protect: 3124 * 3125 * Lower the permission for all mappings to a given page. 3126 */ 3127void 3128pmap_page_protect(vm_page_t m, vm_prot_t prot) 3129{ 3130 if ((prot & VM_PROT_WRITE) == 0) { 3131 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3132 pmap_changebit(m, PG_RW, FALSE); 3133 } else { 3134 pmap_remove_all(m); 3135 } 3136 } 3137} 3138 3139vm_offset_t 3140pmap_phys_address(ppn) 3141 int ppn; 3142{ 3143 return (i386_ptob(ppn)); 3144} 3145 3146/* 3147 * pmap_ts_referenced: 3148 * 3149 * Return a count of reference bits for a page, clearing those bits. 3150 * It is not necessary for every reference bit to be cleared, but it 3151 * is necessary that 0 only be returned when there are truly no 3152 * reference bits set. 3153 * 3154 * XXX: The exact number of bits to check and clear is a matter that 3155 * should be tested and standardized at some point in the future for 3156 * optimal aging of shared pages. 3157 */ 3158int 3159pmap_ts_referenced(vm_page_t m) 3160{ 3161 register pv_entry_t pv, pvf, pvn; 3162 pt_entry_t *pte; 3163 int s; 3164 int rtval = 0; 3165 3166 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3167 return (rtval); 3168 3169 s = splvm(); 3170 3171 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3172 3173 pvf = pv; 3174 3175 do { 3176 pvn = TAILQ_NEXT(pv, pv_list); 3177 3178 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3179 3180 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3181 3182 if (!pmap_track_modified(pv->pv_va)) 3183 continue; 3184 3185 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3186 3187 if (pte && (*pte & PG_A)) { 3188 *pte &= ~PG_A; 3189 3190 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3191 3192 rtval++; 3193 if (rtval > 4) { 3194 break; 3195 } 3196 } 3197 } while ((pv = pvn) != NULL && pv != pvf); 3198 } 3199 splx(s); 3200 3201 return (rtval); 3202} 3203 3204/* 3205 * pmap_is_modified: 3206 * 3207 * Return whether or not the specified physical page was modified 3208 * in any physical maps. 3209 */ 3210boolean_t 3211pmap_is_modified(vm_page_t m) 3212{ 3213 return pmap_testbit(m, PG_M); 3214} 3215 3216/* 3217 * Clear the modify bits on the specified physical page. 3218 */ 3219void 3220pmap_clear_modify(vm_page_t m) 3221{ 3222 pmap_changebit(m, PG_M, FALSE); 3223} 3224 3225/* 3226 * pmap_clear_reference: 3227 * 3228 * Clear the reference bit on the specified physical page. 3229 */ 3230void 3231pmap_clear_reference(vm_page_t m) 3232{ 3233 pmap_changebit(m, PG_A, FALSE); 3234} 3235 3236/* 3237 * Miscellaneous support routines follow 3238 */ 3239 3240static void 3241i386_protection_init() 3242{ 3243 register int *kp, prot; 3244 3245 kp = protection_codes; 3246 for (prot = 0; prot < 8; prot++) { 3247 switch (prot) { 3248 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3249 /* 3250 * Read access is also 0. There isn't any execute bit, 3251 * so just make it readable. 3252 */ 3253 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3254 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3255 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3256 *kp++ = 0; 3257 break; 3258 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3259 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3260 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3261 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3262 *kp++ = PG_RW; 3263 break; 3264 } 3265 } 3266} 3267 3268/* 3269 * Map a set of physical memory pages into the kernel virtual 3270 * address space. Return a pointer to where it is mapped. This 3271 * routine is intended to be used for mapping device memory, 3272 * NOT real memory. 3273 */ 3274void * 3275pmap_mapdev(pa, size) 3276 vm_offset_t pa; 3277 vm_size_t size; 3278{ 3279 vm_offset_t va, tmpva, offset; 3280 pt_entry_t *pte; 3281 3282 offset = pa & PAGE_MASK; 3283 size = roundup(offset + size, PAGE_SIZE); 3284 3285 GIANT_REQUIRED; 3286 3287 va = kmem_alloc_pageable(kernel_map, size); 3288 if (!va) 3289 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3290 3291 pa = pa & PG_FRAME; 3292 for (tmpva = va; size > 0; ) { 3293 pte = vtopte(tmpva); 3294 *pte = pa | PG_RW | PG_V | pgeflag; 3295 size -= PAGE_SIZE; 3296 tmpva += PAGE_SIZE; 3297 pa += PAGE_SIZE; 3298 } 3299 pmap_invalidate_range(kernel_pmap, va, tmpva); 3300 return ((void *)(va + offset)); 3301} 3302 3303void 3304pmap_unmapdev(va, size) 3305 vm_offset_t va; 3306 vm_size_t size; 3307{ 3308 vm_offset_t base, offset, tmpva; 3309 pt_entry_t *pte; 3310 3311 base = va & PG_FRAME; 3312 offset = va & PAGE_MASK; 3313 size = roundup(offset + size, PAGE_SIZE); 3314 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE) { 3315 pte = vtopte(tmpva); 3316 *pte = 0; 3317 } 3318 pmap_invalidate_range(kernel_pmap, va, tmpva); 3319 kmem_free(kernel_map, base, size); 3320} 3321 3322/* 3323 * perform the pmap work for mincore 3324 */ 3325int 3326pmap_mincore(pmap, addr) 3327 pmap_t pmap; 3328 vm_offset_t addr; 3329{ 3330 pt_entry_t *ptep, pte; 3331 vm_page_t m; 3332 int val = 0; 3333 3334 ptep = pmap_pte(pmap, addr); 3335 if (ptep == 0) { 3336 return 0; 3337 } 3338 3339 if ((pte = *ptep) != 0) { 3340 vm_offset_t pa; 3341 3342 val = MINCORE_INCORE; 3343 if ((pte & PG_MANAGED) == 0) 3344 return val; 3345 3346 pa = pte & PG_FRAME; 3347 3348 m = PHYS_TO_VM_PAGE(pa); 3349 3350 /* 3351 * Modified by us 3352 */ 3353 if (pte & PG_M) 3354 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3355 /* 3356 * Modified by someone 3357 */ 3358 else if (m->dirty || pmap_is_modified(m)) 3359 val |= MINCORE_MODIFIED_OTHER; 3360 /* 3361 * Referenced by us 3362 */ 3363 if (pte & PG_A) 3364 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3365 3366 /* 3367 * Referenced by someone 3368 */ 3369 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3370 val |= MINCORE_REFERENCED_OTHER; 3371 vm_page_flag_set(m, PG_REFERENCED); 3372 } 3373 } 3374 return val; 3375} 3376 3377void 3378pmap_activate(struct thread *td) 3379{ 3380 struct proc *p = td->td_proc; 3381 pmap_t pmap; 3382 u_int32_t cr3; 3383 3384 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3385#if defined(SMP) 3386 pmap->pm_active |= PCPU_GET(cpumask); 3387#else 3388 pmap->pm_active |= 1; 3389#endif 3390 cr3 = vtophys(pmap->pm_pdir); 3391 /* XXXKSE this is wrong. 3392 * pmap_activate is for the current thread on the current cpu 3393 */ 3394 if (p->p_flag & P_KSES) { 3395 /* Make sure all other cr3 entries are updated. */ 3396 /* what if they are running? XXXKSE (maybe abort them) */ 3397 FOREACH_THREAD_IN_PROC(p, td) { 3398 td->td_pcb->pcb_cr3 = cr3; 3399 } 3400 } else { 3401 td->td_pcb->pcb_cr3 = cr3; 3402 } 3403 load_cr3(cr3); 3404#ifdef SWTCH_OPTIM_STATS 3405 tlb_flush_count++; 3406#endif 3407} 3408 3409vm_offset_t 3410pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3411{ 3412 3413 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3414 return addr; 3415 } 3416 3417 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3418 return addr; 3419} 3420 3421 3422#if defined(PMAP_DEBUG) 3423pmap_pid_dump(int pid) 3424{ 3425 pmap_t pmap; 3426 struct proc *p; 3427 int npte = 0; 3428 int index; 3429 3430 sx_slock(&allproc_lock); 3431 LIST_FOREACH(p, &allproc, p_list) { 3432 if (p->p_pid != pid) 3433 continue; 3434 3435 if (p->p_vmspace) { 3436 int i,j; 3437 index = 0; 3438 pmap = vmspace_pmap(p->p_vmspace); 3439 for (i = 0; i < NPDEPG; i++) { 3440 pd_entry_t *pde; 3441 pt_entry_t *pte; 3442 vm_offset_t base = i << PDRSHIFT; 3443 3444 pde = &pmap->pm_pdir[i]; 3445 if (pde && pmap_pde_v(pde)) { 3446 for (j = 0; j < NPTEPG; j++) { 3447 vm_offset_t va = base + (j << PAGE_SHIFT); 3448 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3449 if (index) { 3450 index = 0; 3451 printf("\n"); 3452 } 3453 sx_sunlock(&allproc_lock); 3454 return npte; 3455 } 3456 pte = pmap_pte_quick(pmap, va); 3457 if (pte && pmap_pte_v(pte)) { 3458 pt_entry_t pa; 3459 vm_page_t m; 3460 pa = *pte; 3461 m = PHYS_TO_VM_PAGE(pa); 3462 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3463 va, pa, m->hold_count, m->wire_count, m->flags); 3464 npte++; 3465 index++; 3466 if (index >= 2) { 3467 index = 0; 3468 printf("\n"); 3469 } else { 3470 printf(" "); 3471 } 3472 } 3473 } 3474 } 3475 } 3476 } 3477 } 3478 sx_sunlock(&allproc_lock); 3479 return npte; 3480} 3481#endif 3482 3483#if defined(DEBUG) 3484 3485static void pads(pmap_t pm); 3486void pmap_pvdump(vm_offset_t pa); 3487 3488/* print address space of pmap*/ 3489static void 3490pads(pm) 3491 pmap_t pm; 3492{ 3493 int i, j; 3494 vm_offset_t va; 3495 pt_entry_t *ptep; 3496 3497 if (pm == kernel_pmap) 3498 return; 3499 for (i = 0; i < NPDEPG; i++) 3500 if (pm->pm_pdir[i]) 3501 for (j = 0; j < NPTEPG; j++) { 3502 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3503 if (pm == kernel_pmap && va < KERNBASE) 3504 continue; 3505 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3506 continue; 3507 ptep = pmap_pte_quick(pm, va); 3508 if (pmap_pte_v(ptep)) 3509 printf("%x:%x ", va, *ptep); 3510 }; 3511 3512} 3513 3514void 3515pmap_pvdump(pa) 3516 vm_offset_t pa; 3517{ 3518 pv_entry_t pv; 3519 vm_page_t m; 3520 3521 printf("pa %x", pa); 3522 m = PHYS_TO_VM_PAGE(pa); 3523 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3524 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3525 pads(pv->pv_pmap); 3526 } 3527 printf(" "); 3528} 3529#endif 3530