pmap.c revision 100378
10SN/A/* 2157SN/A * Copyright (c) 1991 Regents of the University of California. 30SN/A * All rights reserved. 40SN/A * Copyright (c) 1994 John S. Dyson 50SN/A * All rights reserved. 60SN/A * Copyright (c) 1994 David Greenman 7157SN/A * All rights reserved. 80SN/A * 9157SN/A * This code is derived from software contributed to Berkeley by 100SN/A * the Systems Programming Group of the University of Utah Computer 110SN/A * Science Department and William Jolitz of UUNET Technologies Inc. 120SN/A * 130SN/A * Redistribution and use in source and binary forms, with or without 140SN/A * modification, are permitted provided that the following conditions 150SN/A * are met: 160SN/A * 1. Redistributions of source code must retain the above copyright 170SN/A * notice, this list of conditions and the following disclaimer. 180SN/A * 2. Redistributions in binary form must reproduce the above copyright 190SN/A * notice, this list of conditions and the following disclaimer in the 200SN/A * documentation and/or other materials provided with the distribution. 21157SN/A * 3. All advertising materials mentioning features or use of this software 22157SN/A * must display the following acknowledgement: 23157SN/A * This product includes software developed by the University of 240SN/A * California, Berkeley and its contributors. 250SN/A * 4. Neither the name of the University nor the names of its contributors 260SN/A * may be used to endorse or promote products derived from this software 270SN/A * without specific prior written permission. 280SN/A * 290SN/A * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 300SN/A * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 310SN/A * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 320SN/A * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 330SN/A * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 340SN/A * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 350SN/A * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 360SN/A * 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 100378 2002-07-19 19:35:06Z 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 critical_enter(); 676 /* 677 * We need to disable interrupt preemption but MUST NOT have 678 * interrupts disabled here. 679 * XXX we may need to hold schedlock to get a coherent pm_active 680 */ 681 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 682 invltlb(); 683 smp_invltlb(); 684 } else { 685 cpumask = PCPU_GET(cpumask); 686 other_cpus = PCPU_GET(other_cpus); 687 if (pmap->pm_active & cpumask) 688 invltlb(); 689 if (pmap->pm_active & other_cpus) 690 smp_masked_invltlb(pmap->pm_active & other_cpus); 691 } 692 critical_exit(); 693} 694#else /* !SMP */ 695/* 696 * Normal, non-SMP, 486+ invalidation functions. 697 * We inline these within pmap.c for speed. 698 */ 699PMAP_INLINE void 700pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 701{ 702 703 if (pmap == kernel_pmap || pmap->pm_active) 704 invlpg(va); 705} 706 707PMAP_INLINE void 708pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 709{ 710 vm_offset_t addr; 711 712 if (pmap == kernel_pmap || pmap->pm_active) 713 for (addr = sva; addr < eva; addr += PAGE_SIZE) 714 invlpg(addr); 715} 716 717PMAP_INLINE void 718pmap_invalidate_all(pmap_t pmap) 719{ 720 721 if (pmap == kernel_pmap || pmap->pm_active) 722 invltlb(); 723} 724#endif /* !SMP */ 725#endif /* !I386_CPU */ 726 727/* 728 * Return an address which is the base of the Virtual mapping of 729 * all the PTEs for the given pmap. Note this doesn't say that 730 * all the PTEs will be present or that the pages there are valid. 731 * The PTEs are made available by the recursive mapping trick. 732 * It will map in the alternate PTE space if needed. 733 */ 734static pt_entry_t * 735get_ptbase(pmap) 736 pmap_t pmap; 737{ 738 pd_entry_t frame; 739 740 /* are we current address space or kernel? */ 741 if (pmap == kernel_pmap) 742 return PTmap; 743 frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 744 if (frame == (PTDpde & PG_FRAME)) 745 return PTmap; 746 /* otherwise, we are alternate address space */ 747 if (frame != (APTDpde & PG_FRAME)) { 748 APTDpde = (pd_entry_t) (frame | PG_RW | PG_V); 749 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 750 } 751 return APTmap; 752} 753 754/* 755 * Super fast pmap_pte routine best used when scanning 756 * the pv lists. This eliminates many coarse-grained 757 * invltlb calls. Note that many of the pv list 758 * scans are across different pmaps. It is very wasteful 759 * to do an entire invltlb for checking a single mapping. 760 */ 761 762static pt_entry_t * 763pmap_pte_quick(pmap, va) 764 register pmap_t pmap; 765 vm_offset_t va; 766{ 767 pd_entry_t pde, newpf; 768 pde = pmap->pm_pdir[va >> PDRSHIFT]; 769 if (pde != 0) { 770 pd_entry_t frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 771 unsigned index = i386_btop(va); 772 /* are we current address space or kernel? */ 773 if (pmap == kernel_pmap || frame == (PTDpde & PG_FRAME)) 774 return PTmap + index; 775 newpf = pde & PG_FRAME; 776 if (((*PMAP1) & PG_FRAME) != newpf) { 777 *PMAP1 = newpf | PG_RW | PG_V; 778 pmap_invalidate_page(kernel_pmap, (vm_offset_t)PADDR1); 779 } 780 return PADDR1 + (index & (NPTEPG - 1)); 781 } 782 return (0); 783} 784 785/* 786 * Routine: pmap_extract 787 * Function: 788 * Extract the physical page address associated 789 * with the given map/virtual_address pair. 790 */ 791vm_offset_t 792pmap_extract(pmap, va) 793 register pmap_t pmap; 794 vm_offset_t va; 795{ 796 vm_offset_t rtval; /* XXX FIXME */ 797 vm_offset_t pdirindex; 798 799 if (pmap == 0) 800 return 0; 801 pdirindex = va >> PDRSHIFT; 802 rtval = pmap->pm_pdir[pdirindex]; 803 if (rtval != 0) { 804 pt_entry_t *pte; 805 if ((rtval & PG_PS) != 0) { 806 rtval &= ~(NBPDR - 1); 807 rtval |= va & (NBPDR - 1); 808 return rtval; 809 } 810 pte = get_ptbase(pmap) + i386_btop(va); 811 rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); 812 return rtval; 813 } 814 return 0; 815 816} 817 818/*************************************************** 819 * Low level mapping routines..... 820 ***************************************************/ 821 822/* 823 * Add a wired page to the kva. 824 * Note: not SMP coherent. 825 */ 826PMAP_INLINE void 827pmap_kenter(vm_offset_t va, vm_offset_t pa) 828{ 829 pt_entry_t *pte; 830 831 pte = vtopte(va); 832 *pte = pa | PG_RW | PG_V | pgeflag; 833} 834 835/* 836 * Remove a page from the kernel pagetables. 837 * Note: not SMP coherent. 838 */ 839PMAP_INLINE void 840pmap_kremove(vm_offset_t va) 841{ 842 pt_entry_t *pte; 843 844 pte = vtopte(va); 845 *pte = 0; 846} 847 848/* 849 * Used to map a range of physical addresses into kernel 850 * virtual address space. 851 * 852 * The value passed in '*virt' is a suggested virtual address for 853 * the mapping. Architectures which can support a direct-mapped 854 * physical to virtual region can return the appropriate address 855 * within that region, leaving '*virt' unchanged. Other 856 * architectures should map the pages starting at '*virt' and 857 * update '*virt' with the first usable address after the mapped 858 * region. 859 */ 860vm_offset_t 861pmap_map(vm_offset_t *virt, vm_offset_t start, vm_offset_t end, int prot) 862{ 863 vm_offset_t va, sva; 864 865 va = sva = *virt; 866 while (start < end) { 867 pmap_kenter(va, start); 868 va += PAGE_SIZE; 869 start += PAGE_SIZE; 870 } 871 pmap_invalidate_range(kernel_pmap, sva, va); 872 *virt = va; 873 return (sva); 874} 875 876 877/* 878 * Add a list of wired pages to the kva 879 * this routine is only used for temporary 880 * kernel mappings that do not need to have 881 * page modification or references recorded. 882 * Note that old mappings are simply written 883 * over. The page *must* be wired. 884 * Note: SMP coherent. Uses a ranged shootdown IPI. 885 */ 886void 887pmap_qenter(vm_offset_t sva, vm_page_t *m, int count) 888{ 889 vm_offset_t va; 890 891 va = sva; 892 while (count-- > 0) { 893 pmap_kenter(va, VM_PAGE_TO_PHYS(*m)); 894 va += PAGE_SIZE; 895 m++; 896 } 897 pmap_invalidate_range(kernel_pmap, sva, va); 898} 899 900/* 901 * This routine tears out page mappings from the 902 * kernel -- it is meant only for temporary mappings. 903 * Note: SMP coherent. Uses a ranged shootdown IPI. 904 */ 905void 906pmap_qremove(vm_offset_t sva, int count) 907{ 908 vm_offset_t va; 909 910 va = sva; 911 while (count-- > 0) { 912 pmap_kremove(va); 913 va += PAGE_SIZE; 914 } 915 pmap_invalidate_range(kernel_pmap, sva, va); 916} 917 918static vm_page_t 919pmap_page_lookup(vm_object_t object, vm_pindex_t pindex) 920{ 921 vm_page_t m; 922 923retry: 924 m = vm_page_lookup(object, pindex); 925 if (m && vm_page_sleep_busy(m, FALSE, "pplookp")) 926 goto retry; 927 return m; 928} 929 930/* 931 * Create the kernel stack (including pcb for i386) for a new thread. 932 * This routine directly affects the fork perf for a process and 933 * create performance for a thread. 934 */ 935void 936pmap_new_thread(struct thread *td) 937{ 938 int i; 939 vm_page_t ma[KSTACK_PAGES]; 940 vm_object_t ksobj; 941 vm_page_t m; 942 vm_offset_t ks; 943 944 /* 945 * allocate object for the kstack 946 */ 947 ksobj = vm_object_allocate(OBJT_DEFAULT, KSTACK_PAGES); 948 td->td_kstack_obj = ksobj; 949 950 /* get a kernel virtual address for the kstack for this thread */ 951#ifdef KSTACK_GUARD 952 ks = kmem_alloc_nofault(kernel_map, (KSTACK_PAGES + 1) * PAGE_SIZE); 953 if (ks == 0) 954 panic("pmap_new_thread: kstack allocation failed"); 955 if (*vtopte(ks) != 0) 956 pmap_qremove(ks, 1); 957 ks += PAGE_SIZE; 958 td->td_kstack = ks; 959#else 960 /* get a kernel virtual address for the kstack for this thread */ 961 ks = kmem_alloc_nofault(kernel_map, KSTACK_PAGES * PAGE_SIZE); 962 if (ks == 0) 963 panic("pmap_new_thread: kstack allocation failed"); 964 td->td_kstack = ks; 965#endif 966 /* 967 * For the length of the stack, link in a real page of ram for each 968 * page of stack. 969 */ 970 for (i = 0; i < KSTACK_PAGES; i++) { 971 /* 972 * Get a kernel stack page 973 */ 974 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 975 ma[i] = m; 976 977 /* 978 * Wire the page 979 */ 980 m->wire_count++; 981 cnt.v_wire_count++; 982 983 vm_page_wakeup(m); 984 vm_page_flag_clear(m, PG_ZERO); 985 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 986 m->valid = VM_PAGE_BITS_ALL; 987 } 988 pmap_qenter(ks, ma, KSTACK_PAGES); 989} 990 991/* 992 * Dispose the kernel stack for a thread that has exited. 993 * This routine directly impacts the exit perf of a process and thread. 994 */ 995void 996pmap_dispose_thread(td) 997 struct thread *td; 998{ 999 int i; 1000 vm_object_t ksobj; 1001 vm_offset_t ks; 1002 vm_page_t m; 1003 1004 ksobj = td->td_kstack_obj; 1005 ks = td->td_kstack; 1006 pmap_qremove(ks, KSTACK_PAGES); 1007 for (i = 0; i < KSTACK_PAGES; i++) { 1008 m = vm_page_lookup(ksobj, i); 1009 if (m == NULL) 1010 panic("pmap_dispose_thread: kstack already missing?"); 1011 vm_page_lock_queues(); 1012 vm_page_busy(m); 1013 vm_page_unwire(m, 0); 1014 vm_page_free(m); 1015 vm_page_unlock_queues(); 1016 } 1017 /* 1018 * Free the space that this stack was mapped to in the kernel 1019 * address map. 1020 */ 1021#ifdef KSTACK_GUARD 1022 kmem_free(kernel_map, ks - PAGE_SIZE, (KSTACK_PAGES + 1) * PAGE_SIZE); 1023#else 1024 kmem_free(kernel_map, ks, KSTACK_PAGES * PAGE_SIZE); 1025#endif 1026 vm_object_deallocate(ksobj); 1027} 1028 1029/* 1030 * Allow the Kernel stack for a thread to be prejudicially paged out. 1031 */ 1032void 1033pmap_swapout_thread(td) 1034 struct thread *td; 1035{ 1036 int i; 1037 vm_object_t ksobj; 1038 vm_offset_t ks; 1039 vm_page_t m; 1040 1041 ksobj = td->td_kstack_obj; 1042 ks = td->td_kstack; 1043 pmap_qremove(ks, KSTACK_PAGES); 1044 for (i = 0; i < KSTACK_PAGES; i++) { 1045 m = vm_page_lookup(ksobj, i); 1046 if (m == NULL) 1047 panic("pmap_swapout_thread: kstack already missing?"); 1048 vm_page_lock_queues(); 1049 vm_page_dirty(m); 1050 vm_page_unwire(m, 0); 1051 vm_page_unlock_queues(); 1052 } 1053} 1054 1055/* 1056 * Bring the kernel stack for a specified thread back in. 1057 */ 1058void 1059pmap_swapin_thread(td) 1060 struct thread *td; 1061{ 1062 int i, rv; 1063 vm_page_t ma[KSTACK_PAGES]; 1064 vm_object_t ksobj; 1065 vm_offset_t ks; 1066 vm_page_t m; 1067 1068 ksobj = td->td_kstack_obj; 1069 ks = td->td_kstack; 1070 for (i = 0; i < KSTACK_PAGES; i++) { 1071 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1072 if (m->valid != VM_PAGE_BITS_ALL) { 1073 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1074 if (rv != VM_PAGER_OK) 1075 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1076 m = vm_page_lookup(ksobj, i); 1077 m->valid = VM_PAGE_BITS_ALL; 1078 } 1079 ma[i] = m; 1080 vm_page_lock_queues(); 1081 vm_page_wire(m); 1082 vm_page_wakeup(m); 1083 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 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 1130 vm_page_flash(m); 1131 vm_page_busy(m); 1132 vm_page_free_zero(m); 1133 --cnt.v_wire_count; 1134 } 1135 return 1; 1136 } 1137 return 0; 1138} 1139 1140static PMAP_INLINE int 1141pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1142{ 1143 vm_page_unhold(m); 1144 if (m->hold_count == 0) 1145 return _pmap_unwire_pte_hold(pmap, m); 1146 else 1147 return 0; 1148} 1149 1150/* 1151 * After removing a page table entry, this routine is used to 1152 * conditionally free the page, and manage the hold/wire counts. 1153 */ 1154static int 1155pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1156{ 1157 unsigned ptepindex; 1158 if (va >= VM_MAXUSER_ADDRESS) 1159 return 0; 1160 1161 if (mpte == NULL) { 1162 ptepindex = (va >> PDRSHIFT); 1163 if (pmap->pm_ptphint && 1164 (pmap->pm_ptphint->pindex == ptepindex)) { 1165 mpte = pmap->pm_ptphint; 1166 } else { 1167 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1168 pmap->pm_ptphint = mpte; 1169 } 1170 } 1171 1172 return pmap_unwire_pte_hold(pmap, mpte); 1173} 1174 1175void 1176pmap_pinit0(pmap) 1177 struct pmap *pmap; 1178{ 1179 pmap->pm_pdir = 1180 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1181 pmap_kenter((vm_offset_t)pmap->pm_pdir, (vm_offset_t)IdlePTD); 1182#ifndef I386_CPU 1183 invlpg((vm_offset_t)pmap->pm_pdir); 1184#else 1185 invltlb(); 1186#endif 1187 pmap->pm_ptphint = NULL; 1188 pmap->pm_active = 0; 1189 TAILQ_INIT(&pmap->pm_pvlist); 1190 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1191 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1192} 1193 1194/* 1195 * Initialize a preallocated and zeroed pmap structure, 1196 * such as one in a vmspace structure. 1197 */ 1198void 1199pmap_pinit(pmap) 1200 register struct pmap *pmap; 1201{ 1202 vm_page_t ptdpg; 1203 1204 /* 1205 * No need to allocate page table space yet but we do need a valid 1206 * page directory table. 1207 */ 1208 if (pmap->pm_pdir == NULL) 1209 pmap->pm_pdir = 1210 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1211 1212 /* 1213 * allocate object for the ptes 1214 */ 1215 if (pmap->pm_pteobj == NULL) 1216 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1217 1218 /* 1219 * allocate the page directory page 1220 */ 1221 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1222 VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1223 1224 ptdpg->wire_count = 1; 1225 ++cnt.v_wire_count; 1226 1227 1228 vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/ 1229 ptdpg->valid = VM_PAGE_BITS_ALL; 1230 1231 pmap_qenter((vm_offset_t) pmap->pm_pdir, &ptdpg, 1); 1232 if ((ptdpg->flags & PG_ZERO) == 0) 1233 bzero(pmap->pm_pdir, PAGE_SIZE); 1234 1235 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1236 /* Wire in kernel global address entries. */ 1237 /* XXX copies current process, does not fill in MPPTDI */ 1238 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1239#ifdef SMP 1240 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1241#endif 1242 1243 /* install self-referential address mapping entry */ 1244 pmap->pm_pdir[PTDPTDI] = 1245 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1246 1247 pmap->pm_active = 0; 1248 pmap->pm_ptphint = NULL; 1249 TAILQ_INIT(&pmap->pm_pvlist); 1250 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1251} 1252 1253/* 1254 * Wire in kernel global address entries. To avoid a race condition 1255 * between pmap initialization and pmap_growkernel, this procedure 1256 * should be called after the vmspace is attached to the process 1257 * but before this pmap is activated. 1258 */ 1259void 1260pmap_pinit2(pmap) 1261 struct pmap *pmap; 1262{ 1263 /* XXX: Remove this stub when no longer called */ 1264} 1265 1266static int 1267pmap_release_free_page(pmap_t pmap, vm_page_t p) 1268{ 1269 pd_entry_t *pde = pmap->pm_pdir; 1270 /* 1271 * This code optimizes the case of freeing non-busy 1272 * page-table pages. Those pages are zero now, and 1273 * might as well be placed directly into the zero queue. 1274 */ 1275 if (vm_page_sleep_busy(p, FALSE, "pmaprl")) 1276 return 0; 1277 1278 vm_page_busy(p); 1279 1280 /* 1281 * Remove the page table page from the processes address space. 1282 */ 1283 pde[p->pindex] = 0; 1284 pmap->pm_stats.resident_count--; 1285 1286 if (p->hold_count) { 1287 panic("pmap_release: freeing held page table page"); 1288 } 1289 /* 1290 * Page directory pages need to have the kernel 1291 * stuff cleared, so they can go into the zero queue also. 1292 */ 1293 if (p->pindex == PTDPTDI) { 1294 bzero(pde + KPTDI, nkpt * PTESIZE); 1295#ifdef SMP 1296 pde[MPPTDI] = 0; 1297#endif 1298 pde[APTDPTDI] = 0; 1299 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1300 } 1301 1302 if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex)) 1303 pmap->pm_ptphint = NULL; 1304 1305 p->wire_count--; 1306 cnt.v_wire_count--; 1307 vm_page_free_zero(p); 1308 return 1; 1309} 1310 1311/* 1312 * this routine is called if the page table page is not 1313 * mapped correctly. 1314 */ 1315static vm_page_t 1316_pmap_allocpte(pmap, ptepindex) 1317 pmap_t pmap; 1318 unsigned ptepindex; 1319{ 1320 vm_offset_t pteva, ptepa; /* XXXPA */ 1321 vm_page_t m; 1322 1323 /* 1324 * Find or fabricate a new pagetable page 1325 */ 1326 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1327 VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1328 1329 KASSERT(m->queue == PQ_NONE, 1330 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1331 1332 if (m->wire_count == 0) 1333 cnt.v_wire_count++; 1334 m->wire_count++; 1335 1336 /* 1337 * Increment the hold count for the page table page 1338 * (denoting a new mapping.) 1339 */ 1340 m->hold_count++; 1341 1342 /* 1343 * Map the pagetable page into the process address space, if 1344 * it isn't already there. 1345 */ 1346 1347 pmap->pm_stats.resident_count++; 1348 1349 ptepa = VM_PAGE_TO_PHYS(m); 1350 pmap->pm_pdir[ptepindex] = 1351 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1352 1353 /* 1354 * Set the page table hint 1355 */ 1356 pmap->pm_ptphint = m; 1357 1358 /* 1359 * Try to use the new mapping, but if we cannot, then 1360 * do it with the routine that maps the page explicitly. 1361 */ 1362 if ((m->flags & PG_ZERO) == 0) { 1363 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1364 (PTDpde & PG_FRAME)) { 1365 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1366 bzero((caddr_t) pteva, PAGE_SIZE); 1367 } else { 1368 pmap_zero_page(m); 1369 } 1370 } 1371 1372 m->valid = VM_PAGE_BITS_ALL; 1373 vm_page_flag_clear(m, PG_ZERO); 1374 vm_page_flag_set(m, PG_MAPPED); 1375 vm_page_wakeup(m); 1376 1377 return m; 1378} 1379 1380static vm_page_t 1381pmap_allocpte(pmap_t pmap, vm_offset_t va) 1382{ 1383 unsigned ptepindex; 1384 pd_entry_t ptepa; 1385 vm_page_t m; 1386 1387 /* 1388 * Calculate pagetable page index 1389 */ 1390 ptepindex = va >> PDRSHIFT; 1391 1392 /* 1393 * Get the page directory entry 1394 */ 1395 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1396 1397 /* 1398 * This supports switching from a 4MB page to a 1399 * normal 4K page. 1400 */ 1401 if (ptepa & PG_PS) { 1402 pmap->pm_pdir[ptepindex] = 0; 1403 ptepa = 0; 1404 pmap_invalidate_all(kernel_pmap); 1405 } 1406 1407 /* 1408 * If the page table page is mapped, we just increment the 1409 * hold count, and activate it. 1410 */ 1411 if (ptepa) { 1412 /* 1413 * In order to get the page table page, try the 1414 * hint first. 1415 */ 1416 if (pmap->pm_ptphint && 1417 (pmap->pm_ptphint->pindex == ptepindex)) { 1418 m = pmap->pm_ptphint; 1419 } else { 1420 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1421 pmap->pm_ptphint = m; 1422 } 1423 m->hold_count++; 1424 return m; 1425 } 1426 /* 1427 * Here if the pte page isn't mapped, or if it has been deallocated. 1428 */ 1429 return _pmap_allocpte(pmap, ptepindex); 1430} 1431 1432 1433/*************************************************** 1434* Pmap allocation/deallocation routines. 1435 ***************************************************/ 1436 1437/* 1438 * Release any resources held by the given physical map. 1439 * Called when a pmap initialized by pmap_pinit is being released. 1440 * Should only be called if the map contains no valid mappings. 1441 */ 1442void 1443pmap_release(pmap_t pmap) 1444{ 1445 vm_page_t p,n,ptdpg; 1446 vm_object_t object = pmap->pm_pteobj; 1447 int curgeneration; 1448 1449#if defined(DIAGNOSTIC) 1450 if (object->ref_count != 1) 1451 panic("pmap_release: pteobj reference count != 1"); 1452#endif 1453 1454 ptdpg = NULL; 1455 LIST_REMOVE(pmap, pm_list); 1456retry: 1457 curgeneration = object->generation; 1458 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1459 n = TAILQ_NEXT(p, listq); 1460 if (p->pindex == PTDPTDI) { 1461 ptdpg = p; 1462 continue; 1463 } 1464 while (1) { 1465 if (!pmap_release_free_page(pmap, p) && 1466 (object->generation != curgeneration)) 1467 goto retry; 1468 } 1469 } 1470 1471 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1472 goto retry; 1473} 1474 1475static int 1476kvm_size(SYSCTL_HANDLER_ARGS) 1477{ 1478 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1479 1480 return sysctl_handle_long(oidp, &ksize, 0, req); 1481} 1482SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1483 0, 0, kvm_size, "IU", "Size of KVM"); 1484 1485static int 1486kvm_free(SYSCTL_HANDLER_ARGS) 1487{ 1488 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1489 1490 return sysctl_handle_long(oidp, &kfree, 0, req); 1491} 1492SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1493 0, 0, kvm_free, "IU", "Amount of KVM free"); 1494 1495/* 1496 * grow the number of kernel page table entries, if needed 1497 */ 1498void 1499pmap_growkernel(vm_offset_t addr) 1500{ 1501 struct pmap *pmap; 1502 int s; 1503 vm_offset_t ptppaddr; 1504 vm_page_t nkpg; 1505 pd_entry_t newpdir; 1506 1507 s = splhigh(); 1508 if (kernel_vm_end == 0) { 1509 kernel_vm_end = KERNBASE; 1510 nkpt = 0; 1511 while (pdir_pde(PTD, kernel_vm_end)) { 1512 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1513 nkpt++; 1514 } 1515 } 1516 addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1517 while (kernel_vm_end < addr) { 1518 if (pdir_pde(PTD, kernel_vm_end)) { 1519 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1520 continue; 1521 } 1522 1523 /* 1524 * This index is bogus, but out of the way 1525 */ 1526 nkpg = vm_page_alloc(kptobj, nkpt, 1527 VM_ALLOC_SYSTEM | VM_ALLOC_WIRED); 1528 if (!nkpg) 1529 panic("pmap_growkernel: no memory to grow kernel"); 1530 1531 nkpt++; 1532 1533 pmap_zero_page(nkpg); 1534 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1535 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1536 pdir_pde(PTD, kernel_vm_end) = newpdir; 1537 1538 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1539 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1540 } 1541 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1542 } 1543 splx(s); 1544} 1545 1546 1547/*************************************************** 1548 * page management routines. 1549 ***************************************************/ 1550 1551/* 1552 * free the pv_entry back to the free list 1553 */ 1554static PMAP_INLINE void 1555free_pv_entry(pv_entry_t pv) 1556{ 1557 pv_entry_count--; 1558 uma_zfree(pvzone, pv); 1559} 1560 1561/* 1562 * get a new pv_entry, allocating a block from the system 1563 * when needed. 1564 * the memory allocation is performed bypassing the malloc code 1565 * because of the possibility of allocations at interrupt time. 1566 */ 1567static pv_entry_t 1568get_pv_entry(void) 1569{ 1570 pv_entry_count++; 1571 if (pv_entry_high_water && 1572 (pv_entry_count > pv_entry_high_water) && 1573 (pmap_pagedaemon_waken == 0)) { 1574 pmap_pagedaemon_waken = 1; 1575 wakeup (&vm_pages_needed); 1576 } 1577 return uma_zalloc(pvzone, M_NOWAIT); 1578} 1579 1580/* 1581 * This routine is very drastic, but can save the system 1582 * in a pinch. 1583 */ 1584void 1585pmap_collect() 1586{ 1587 int i; 1588 vm_page_t m; 1589 static int warningdone = 0; 1590 1591 if (pmap_pagedaemon_waken == 0) 1592 return; 1593 1594 if (warningdone < 5) { 1595 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1596 warningdone++; 1597 } 1598 1599 for(i = 0; i < vm_page_array_size; i++) { 1600 m = &vm_page_array[i]; 1601 if (m->wire_count || m->hold_count || m->busy || 1602 (m->flags & (PG_BUSY | PG_UNMANAGED))) 1603 continue; 1604 pmap_remove_all(m); 1605 } 1606 pmap_pagedaemon_waken = 0; 1607} 1608 1609 1610/* 1611 * If it is the first entry on the list, it is actually 1612 * in the header and we must copy the following entry up 1613 * to the header. Otherwise we must search the list for 1614 * the entry. In either case we free the now unused entry. 1615 */ 1616 1617static int 1618pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1619{ 1620 pv_entry_t pv; 1621 int rtval; 1622 int s; 1623 1624 s = splvm(); 1625 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1626 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1627 if (pmap == pv->pv_pmap && va == pv->pv_va) 1628 break; 1629 } 1630 } else { 1631 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1632 if (va == pv->pv_va) 1633 break; 1634 } 1635 } 1636 1637 rtval = 0; 1638 if (pv) { 1639 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1640 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1641 m->md.pv_list_count--; 1642 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1643 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1644 1645 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1646 free_pv_entry(pv); 1647 } 1648 1649 splx(s); 1650 return rtval; 1651} 1652 1653/* 1654 * Create a pv entry for page at pa for 1655 * (pmap, va). 1656 */ 1657static void 1658pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1659{ 1660 1661 int s; 1662 pv_entry_t pv; 1663 1664 s = splvm(); 1665 pv = get_pv_entry(); 1666 pv->pv_va = va; 1667 pv->pv_pmap = pmap; 1668 pv->pv_ptem = mpte; 1669 1670 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1671 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1672 m->md.pv_list_count++; 1673 1674 splx(s); 1675} 1676 1677/* 1678 * pmap_remove_pte: do the things to unmap a page in a process 1679 */ 1680static int 1681pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1682{ 1683 pt_entry_t oldpte; 1684 vm_page_t m; 1685 1686 oldpte = atomic_readandclear_int(ptq); 1687 if (oldpte & PG_W) 1688 pmap->pm_stats.wired_count -= 1; 1689 /* 1690 * Machines that don't support invlpg, also don't support 1691 * PG_G. 1692 */ 1693 if (oldpte & PG_G) 1694 pmap_invalidate_page(kernel_pmap, va); 1695 pmap->pm_stats.resident_count -= 1; 1696 if (oldpte & PG_MANAGED) { 1697 m = PHYS_TO_VM_PAGE(oldpte); 1698 if (oldpte & PG_M) { 1699#if defined(PMAP_DIAGNOSTIC) 1700 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1701 printf( 1702 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1703 va, oldpte); 1704 } 1705#endif 1706 if (pmap_track_modified(va)) 1707 vm_page_dirty(m); 1708 } 1709 if (oldpte & PG_A) 1710 vm_page_flag_set(m, PG_REFERENCED); 1711 return pmap_remove_entry(pmap, m, va); 1712 } else { 1713 return pmap_unuse_pt(pmap, va, NULL); 1714 } 1715 1716 return 0; 1717} 1718 1719/* 1720 * Remove a single page from a process address space 1721 */ 1722static void 1723pmap_remove_page(pmap_t pmap, vm_offset_t va) 1724{ 1725 register pt_entry_t *ptq; 1726 1727 /* 1728 * if there is no pte for this address, just skip it!!! 1729 */ 1730 if (*pmap_pde(pmap, va) == 0) { 1731 return; 1732 } 1733 1734 /* 1735 * get a local va for mappings for this pmap. 1736 */ 1737 ptq = get_ptbase(pmap) + i386_btop(va); 1738 if (*ptq) { 1739 (void) pmap_remove_pte(pmap, ptq, va); 1740 pmap_invalidate_page(pmap, va); 1741 } 1742 return; 1743} 1744 1745/* 1746 * Remove the given range of addresses from the specified map. 1747 * 1748 * It is assumed that the start and end are properly 1749 * rounded to the page size. 1750 */ 1751void 1752pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1753{ 1754 register pt_entry_t *ptbase; 1755 vm_offset_t pdnxt; 1756 pd_entry_t ptpaddr; 1757 vm_offset_t sindex, eindex; 1758 int anyvalid; 1759 1760 if (pmap == NULL) 1761 return; 1762 1763 if (pmap->pm_stats.resident_count == 0) 1764 return; 1765 1766 /* 1767 * special handling of removing one page. a very 1768 * common operation and easy to short circuit some 1769 * code. 1770 */ 1771 if ((sva + PAGE_SIZE == eva) && 1772 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1773 pmap_remove_page(pmap, sva); 1774 return; 1775 } 1776 1777 anyvalid = 0; 1778 1779 /* 1780 * Get a local virtual address for the mappings that are being 1781 * worked with. 1782 */ 1783 ptbase = get_ptbase(pmap); 1784 1785 sindex = i386_btop(sva); 1786 eindex = i386_btop(eva); 1787 1788 for (; sindex < eindex; sindex = pdnxt) { 1789 unsigned pdirindex; 1790 1791 /* 1792 * Calculate index for next page table. 1793 */ 1794 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1795 if (pmap->pm_stats.resident_count == 0) 1796 break; 1797 1798 pdirindex = sindex / NPDEPG; 1799 ptpaddr = pmap->pm_pdir[pdirindex]; 1800 if ((ptpaddr & PG_PS) != 0) { 1801 pmap->pm_pdir[pdirindex] = 0; 1802 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1803 anyvalid++; 1804 continue; 1805 } 1806 1807 /* 1808 * Weed out invalid mappings. Note: we assume that the page 1809 * directory table is always allocated, and in kernel virtual. 1810 */ 1811 if (ptpaddr == 0) 1812 continue; 1813 1814 /* 1815 * Limit our scan to either the end of the va represented 1816 * by the current page table page, or to the end of the 1817 * range being removed. 1818 */ 1819 if (pdnxt > eindex) { 1820 pdnxt = eindex; 1821 } 1822 1823 for (; sindex != pdnxt; sindex++) { 1824 vm_offset_t va; 1825 if (ptbase[sindex] == 0) { 1826 continue; 1827 } 1828 va = i386_ptob(sindex); 1829 1830 anyvalid++; 1831 if (pmap_remove_pte(pmap, 1832 ptbase + sindex, va)) 1833 break; 1834 } 1835 } 1836 1837 if (anyvalid) 1838 pmap_invalidate_all(pmap); 1839} 1840 1841/* 1842 * Routine: pmap_remove_all 1843 * Function: 1844 * Removes this physical page from 1845 * all physical maps in which it resides. 1846 * Reflects back modify bits to the pager. 1847 * 1848 * Notes: 1849 * Original versions of this routine were very 1850 * inefficient because they iteratively called 1851 * pmap_remove (slow...) 1852 */ 1853 1854static void 1855pmap_remove_all(vm_page_t m) 1856{ 1857 register pv_entry_t pv; 1858 pt_entry_t *pte, tpte; 1859 int s; 1860 1861#if defined(PMAP_DIAGNOSTIC) 1862 /* 1863 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1864 * pages! 1865 */ 1866 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1867 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1868 } 1869#endif 1870 1871 s = splvm(); 1872 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1873 pv->pv_pmap->pm_stats.resident_count--; 1874 1875 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1876 1877 tpte = atomic_readandclear_int(pte); 1878 if (tpte & PG_W) 1879 pv->pv_pmap->pm_stats.wired_count--; 1880 1881 if (tpte & PG_A) 1882 vm_page_flag_set(m, PG_REFERENCED); 1883 1884 /* 1885 * Update the vm_page_t clean and reference bits. 1886 */ 1887 if (tpte & PG_M) { 1888#if defined(PMAP_DIAGNOSTIC) 1889 if (pmap_nw_modified((pt_entry_t) tpte)) { 1890 printf( 1891 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1892 pv->pv_va, tpte); 1893 } 1894#endif 1895 if (pmap_track_modified(pv->pv_va)) 1896 vm_page_dirty(m); 1897 } 1898 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1899 1900 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1901 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1902 m->md.pv_list_count--; 1903 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1904 free_pv_entry(pv); 1905 } 1906 1907 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1908 1909 splx(s); 1910} 1911 1912/* 1913 * Set the physical protection on the 1914 * specified range of this map as requested. 1915 */ 1916void 1917pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1918{ 1919 register pt_entry_t *ptbase; 1920 vm_offset_t pdnxt; 1921 pd_entry_t ptpaddr; 1922 vm_offset_t sindex, eindex; 1923 int anychanged; 1924 1925 if (pmap == NULL) 1926 return; 1927 1928 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1929 pmap_remove(pmap, sva, eva); 1930 return; 1931 } 1932 1933 if (prot & VM_PROT_WRITE) 1934 return; 1935 1936 anychanged = 0; 1937 1938 ptbase = get_ptbase(pmap); 1939 1940 sindex = i386_btop(sva); 1941 eindex = i386_btop(eva); 1942 1943 for (; sindex < eindex; sindex = pdnxt) { 1944 1945 unsigned pdirindex; 1946 1947 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1948 1949 pdirindex = sindex / NPDEPG; 1950 ptpaddr = pmap->pm_pdir[pdirindex]; 1951 if ((ptpaddr & PG_PS) != 0) { 1952 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1953 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1954 anychanged++; 1955 continue; 1956 } 1957 1958 /* 1959 * Weed out invalid mappings. Note: we assume that the page 1960 * directory table is always allocated, and in kernel virtual. 1961 */ 1962 if (ptpaddr == 0) 1963 continue; 1964 1965 if (pdnxt > eindex) { 1966 pdnxt = eindex; 1967 } 1968 1969 for (; sindex != pdnxt; sindex++) { 1970 1971 pt_entry_t pbits; 1972 vm_page_t m; 1973 1974 pbits = ptbase[sindex]; 1975 1976 if (pbits & PG_MANAGED) { 1977 m = NULL; 1978 if (pbits & PG_A) { 1979 m = PHYS_TO_VM_PAGE(pbits); 1980 vm_page_flag_set(m, PG_REFERENCED); 1981 pbits &= ~PG_A; 1982 } 1983 if (pbits & PG_M) { 1984 if (pmap_track_modified(i386_ptob(sindex))) { 1985 if (m == NULL) 1986 m = PHYS_TO_VM_PAGE(pbits); 1987 vm_page_dirty(m); 1988 pbits &= ~PG_M; 1989 } 1990 } 1991 } 1992 1993 pbits &= ~PG_RW; 1994 1995 if (pbits != ptbase[sindex]) { 1996 ptbase[sindex] = pbits; 1997 anychanged = 1; 1998 } 1999 } 2000 } 2001 if (anychanged) 2002 pmap_invalidate_all(pmap); 2003} 2004 2005/* 2006 * Insert the given physical page (p) at 2007 * the specified virtual address (v) in the 2008 * target physical map with the protection requested. 2009 * 2010 * If specified, the page will be wired down, meaning 2011 * that the related pte can not be reclaimed. 2012 * 2013 * NB: This is the only routine which MAY NOT lazy-evaluate 2014 * or lose information. That is, this routine must actually 2015 * insert this page into the given map NOW. 2016 */ 2017void 2018pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2019 boolean_t wired) 2020{ 2021 vm_offset_t pa; 2022 register pt_entry_t *pte; 2023 vm_offset_t opa; 2024 pt_entry_t origpte, newpte; 2025 vm_page_t mpte; 2026 2027 if (pmap == NULL) 2028 return; 2029 2030 va &= PG_FRAME; 2031#ifdef PMAP_DIAGNOSTIC 2032 if (va > VM_MAX_KERNEL_ADDRESS) 2033 panic("pmap_enter: toobig"); 2034 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2035 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2036#endif 2037 2038 mpte = NULL; 2039 /* 2040 * In the case that a page table page is not 2041 * resident, we are creating it here. 2042 */ 2043 if (va < VM_MAXUSER_ADDRESS) { 2044 mpte = pmap_allocpte(pmap, va); 2045 } 2046#if 0 && defined(PMAP_DIAGNOSTIC) 2047 else { 2048 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2049 origpte = *pdeaddr; 2050 if ((origpte & PG_V) == 0) { 2051 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2052 pmap->pm_pdir[PTDPTDI], origpte, va); 2053 } 2054 } 2055#endif 2056 2057 pte = pmap_pte(pmap, va); 2058 2059 /* 2060 * Page Directory table entry not valid, we need a new PT page 2061 */ 2062 if (pte == NULL) { 2063 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2064 (void *)pmap->pm_pdir[PTDPTDI], va); 2065 } 2066 2067 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2068 origpte = *(vm_offset_t *)pte; 2069 opa = origpte & PG_FRAME; 2070 2071 if (origpte & PG_PS) 2072 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2073 2074 /* 2075 * Mapping has not changed, must be protection or wiring change. 2076 */ 2077 if (origpte && (opa == pa)) { 2078 /* 2079 * Wiring change, just update stats. We don't worry about 2080 * wiring PT pages as they remain resident as long as there 2081 * are valid mappings in them. Hence, if a user page is wired, 2082 * the PT page will be also. 2083 */ 2084 if (wired && ((origpte & PG_W) == 0)) 2085 pmap->pm_stats.wired_count++; 2086 else if (!wired && (origpte & PG_W)) 2087 pmap->pm_stats.wired_count--; 2088 2089#if defined(PMAP_DIAGNOSTIC) 2090 if (pmap_nw_modified((pt_entry_t) origpte)) { 2091 printf( 2092 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2093 va, origpte); 2094 } 2095#endif 2096 2097 /* 2098 * Remove extra pte reference 2099 */ 2100 if (mpte) 2101 mpte->hold_count--; 2102 2103 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2104 if ((origpte & PG_RW) == 0) { 2105 *pte |= PG_RW; 2106 pmap_invalidate_page(pmap, va); 2107 } 2108 return; 2109 } 2110 2111 /* 2112 * We might be turning off write access to the page, 2113 * so we go ahead and sense modify status. 2114 */ 2115 if (origpte & PG_MANAGED) { 2116 if ((origpte & PG_M) && pmap_track_modified(va)) { 2117 vm_page_t om; 2118 om = PHYS_TO_VM_PAGE(opa); 2119 vm_page_dirty(om); 2120 } 2121 pa |= PG_MANAGED; 2122 } 2123 goto validate; 2124 } 2125 /* 2126 * Mapping has changed, invalidate old range and fall through to 2127 * handle validating new mapping. 2128 */ 2129 if (opa) { 2130 int err; 2131 err = pmap_remove_pte(pmap, pte, va); 2132 if (err) 2133 panic("pmap_enter: pte vanished, va: 0x%x", va); 2134 } 2135 2136 /* 2137 * Enter on the PV list if part of our managed memory. Note that we 2138 * raise IPL while manipulating pv_table since pmap_enter can be 2139 * called at interrupt time. 2140 */ 2141 if (pmap_initialized && 2142 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2143 pmap_insert_entry(pmap, va, mpte, m); 2144 pa |= PG_MANAGED; 2145 } 2146 2147 /* 2148 * Increment counters 2149 */ 2150 pmap->pm_stats.resident_count++; 2151 if (wired) 2152 pmap->pm_stats.wired_count++; 2153 2154validate: 2155 /* 2156 * Now validate mapping with desired protection/wiring. 2157 */ 2158 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2159 2160 if (wired) 2161 newpte |= PG_W; 2162 if (va < VM_MAXUSER_ADDRESS) 2163 newpte |= PG_U; 2164 if (pmap == kernel_pmap) 2165 newpte |= pgeflag; 2166 2167 /* 2168 * if the mapping or permission bits are different, we need 2169 * to update the pte. 2170 */ 2171 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2172 *pte = newpte | PG_A; 2173 /*if (origpte)*/ { 2174 pmap_invalidate_page(pmap, va); 2175 } 2176 } 2177} 2178 2179/* 2180 * this code makes some *MAJOR* assumptions: 2181 * 1. Current pmap & pmap exists. 2182 * 2. Not wired. 2183 * 3. Read access. 2184 * 4. No page table pages. 2185 * 5. Tlbflush is deferred to calling procedure. 2186 * 6. Page IS managed. 2187 * but is *MUCH* faster than pmap_enter... 2188 */ 2189 2190static vm_page_t 2191pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2192{ 2193 pt_entry_t *pte; 2194 vm_offset_t pa; 2195 2196 /* 2197 * In the case that a page table page is not 2198 * resident, we are creating it here. 2199 */ 2200 if (va < VM_MAXUSER_ADDRESS) { 2201 unsigned ptepindex; 2202 pd_entry_t ptepa; 2203 2204 /* 2205 * Calculate pagetable page index 2206 */ 2207 ptepindex = va >> PDRSHIFT; 2208 if (mpte && (mpte->pindex == ptepindex)) { 2209 mpte->hold_count++; 2210 } else { 2211retry: 2212 /* 2213 * Get the page directory entry 2214 */ 2215 ptepa = pmap->pm_pdir[ptepindex]; 2216 2217 /* 2218 * If the page table page is mapped, we just increment 2219 * the hold count, and activate it. 2220 */ 2221 if (ptepa) { 2222 if (ptepa & PG_PS) 2223 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2224 if (pmap->pm_ptphint && 2225 (pmap->pm_ptphint->pindex == ptepindex)) { 2226 mpte = pmap->pm_ptphint; 2227 } else { 2228 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2229 pmap->pm_ptphint = mpte; 2230 } 2231 if (mpte == NULL) 2232 goto retry; 2233 mpte->hold_count++; 2234 } else { 2235 mpte = _pmap_allocpte(pmap, ptepindex); 2236 } 2237 } 2238 } else { 2239 mpte = NULL; 2240 } 2241 2242 /* 2243 * This call to vtopte makes the assumption that we are 2244 * entering the page into the current pmap. In order to support 2245 * quick entry into any pmap, one would likely use pmap_pte_quick. 2246 * But that isn't as quick as vtopte. 2247 */ 2248 pte = vtopte(va); 2249 if (*pte) { 2250 if (mpte) 2251 pmap_unwire_pte_hold(pmap, mpte); 2252 return 0; 2253 } 2254 2255 /* 2256 * Enter on the PV list if part of our managed memory. Note that we 2257 * raise IPL while manipulating pv_table since pmap_enter can be 2258 * called at interrupt time. 2259 */ 2260 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2261 pmap_insert_entry(pmap, va, mpte, m); 2262 2263 /* 2264 * Increment counters 2265 */ 2266 pmap->pm_stats.resident_count++; 2267 2268 pa = VM_PAGE_TO_PHYS(m); 2269 2270 /* 2271 * Now validate mapping with RO protection 2272 */ 2273 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2274 *pte = pa | PG_V | PG_U; 2275 else 2276 *pte = pa | PG_V | PG_U | PG_MANAGED; 2277 2278 return mpte; 2279} 2280 2281/* 2282 * Make a temporary mapping for a physical address. This is only intended 2283 * to be used for panic dumps. 2284 */ 2285void * 2286pmap_kenter_temporary(vm_offset_t pa, int i) 2287{ 2288 vm_offset_t va; 2289 2290 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE); 2291 pmap_kenter(va, pa); 2292#ifndef I386_CPU 2293 invlpg(va); 2294#else 2295 invltlb(); 2296#endif 2297 return ((void *)crashdumpmap); 2298} 2299 2300#define MAX_INIT_PT (96) 2301/* 2302 * pmap_object_init_pt preloads the ptes for a given object 2303 * into the specified pmap. This eliminates the blast of soft 2304 * faults on process startup and immediately after an mmap. 2305 */ 2306void 2307pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2308 vm_object_t object, vm_pindex_t pindex, 2309 vm_size_t size, int limit) 2310{ 2311 vm_offset_t tmpidx; 2312 int psize; 2313 vm_page_t p, mpte; 2314 int objpgs; 2315 2316 if (pmap == NULL || object == NULL) 2317 return; 2318 2319 /* 2320 * This code maps large physical mmap regions into the 2321 * processor address space. Note that some shortcuts 2322 * are taken, but the code works. 2323 */ 2324 if (pseflag && (object->type == OBJT_DEVICE) && 2325 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2326 int i; 2327 vm_page_t m[1]; 2328 unsigned int ptepindex; 2329 int npdes; 2330 pd_entry_t ptepa; 2331 2332 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2333 return; 2334 2335retry: 2336 p = vm_page_lookup(object, pindex); 2337 if (p && vm_page_sleep_busy(p, FALSE, "init4p")) 2338 goto retry; 2339 2340 if (p == NULL) { 2341 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2342 if (p == NULL) 2343 return; 2344 m[0] = p; 2345 2346 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2347 vm_page_free(p); 2348 return; 2349 } 2350 2351 p = vm_page_lookup(object, pindex); 2352 vm_page_wakeup(p); 2353 } 2354 2355 ptepa = VM_PAGE_TO_PHYS(p); 2356 if (ptepa & (NBPDR - 1)) { 2357 return; 2358 } 2359 2360 p->valid = VM_PAGE_BITS_ALL; 2361 2362 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2363 npdes = size >> PDRSHIFT; 2364 for(i = 0; i < npdes; i++) { 2365 pmap->pm_pdir[ptepindex] = 2366 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2367 ptepa += NBPDR; 2368 ptepindex += 1; 2369 } 2370 vm_page_flag_set(p, PG_MAPPED); 2371 pmap_invalidate_all(kernel_pmap); 2372 return; 2373 } 2374 2375 psize = i386_btop(size); 2376 2377 if ((object->type != OBJT_VNODE) || 2378 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2379 (object->resident_page_count > MAX_INIT_PT))) { 2380 return; 2381 } 2382 2383 if (psize + pindex > object->size) { 2384 if (object->size < pindex) 2385 return; 2386 psize = object->size - pindex; 2387 } 2388 2389 mpte = NULL; 2390 /* 2391 * if we are processing a major portion of the object, then scan the 2392 * entire thing. 2393 */ 2394 if (psize > (object->resident_page_count >> 2)) { 2395 objpgs = psize; 2396 2397 for (p = TAILQ_FIRST(&object->memq); 2398 ((objpgs > 0) && (p != NULL)); 2399 p = TAILQ_NEXT(p, listq)) { 2400 2401 if (p->pindex < pindex || p->pindex - pindex >= psize) { 2402 continue; 2403 } 2404 tmpidx = p->pindex - pindex; 2405 /* 2406 * don't allow an madvise to blow away our really 2407 * free pages allocating pv entries. 2408 */ 2409 if ((limit & MAP_PREFAULT_MADVISE) && 2410 cnt.v_free_count < cnt.v_free_reserved) { 2411 break; 2412 } 2413 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2414 (p->busy == 0) && 2415 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2416 if ((p->queue - p->pc) == PQ_CACHE) 2417 vm_page_deactivate(p); 2418 vm_page_busy(p); 2419 mpte = pmap_enter_quick(pmap, 2420 addr + i386_ptob(tmpidx), p, mpte); 2421 vm_page_flag_set(p, PG_MAPPED); 2422 vm_page_wakeup(p); 2423 } 2424 objpgs -= 1; 2425 } 2426 } else { 2427 /* 2428 * else lookup the pages one-by-one. 2429 */ 2430 for (tmpidx = 0; tmpidx < psize; tmpidx += 1) { 2431 /* 2432 * don't allow an madvise to blow away our really 2433 * free pages allocating pv entries. 2434 */ 2435 if ((limit & MAP_PREFAULT_MADVISE) && 2436 cnt.v_free_count < cnt.v_free_reserved) { 2437 break; 2438 } 2439 p = vm_page_lookup(object, tmpidx + pindex); 2440 if (p && 2441 ((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 mpte = pmap_enter_quick(pmap, 2448 addr + i386_ptob(tmpidx), p, mpte); 2449 vm_page_flag_set(p, PG_MAPPED); 2450 vm_page_wakeup(p); 2451 } 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)) == NULL) 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 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 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2544 vm_page_flag_set(m, PG_MAPPED); 2545 vm_page_wakeup(m); 2546 } 2547 } 2548} 2549 2550/* 2551 * Routine: pmap_change_wiring 2552 * Function: Change the wiring attribute for a map/virtual-address 2553 * pair. 2554 * In/out conditions: 2555 * The mapping must already exist in the pmap. 2556 */ 2557void 2558pmap_change_wiring(pmap, va, wired) 2559 register pmap_t pmap; 2560 vm_offset_t va; 2561 boolean_t wired; 2562{ 2563 register pt_entry_t *pte; 2564 2565 if (pmap == NULL) 2566 return; 2567 2568 pte = pmap_pte(pmap, va); 2569 2570 if (wired && !pmap_pte_w(pte)) 2571 pmap->pm_stats.wired_count++; 2572 else if (!wired && pmap_pte_w(pte)) 2573 pmap->pm_stats.wired_count--; 2574 2575 /* 2576 * Wiring is not a hardware characteristic so there is no need to 2577 * invalidate TLB. 2578 */ 2579 pmap_pte_set_w(pte, wired); 2580} 2581 2582 2583 2584/* 2585 * Copy the range specified by src_addr/len 2586 * from the source map to the range dst_addr/len 2587 * in the destination map. 2588 * 2589 * This routine is only advisory and need not do anything. 2590 */ 2591 2592void 2593pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2594 vm_offset_t src_addr) 2595{ 2596 vm_offset_t addr; 2597 vm_offset_t end_addr = src_addr + len; 2598 vm_offset_t pdnxt; 2599 pd_entry_t src_frame, dst_frame; 2600 vm_page_t m; 2601 2602 if (dst_addr != src_addr) 2603 return; 2604 2605 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2606 if (src_frame != (PTDpde & PG_FRAME)) 2607 return; 2608 2609 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2610 for (addr = src_addr; addr < end_addr; addr = pdnxt) { 2611 pt_entry_t *src_pte, *dst_pte; 2612 vm_page_t dstmpte, srcmpte; 2613 pd_entry_t srcptepaddr; 2614 unsigned ptepindex; 2615 2616 if (addr >= UPT_MIN_ADDRESS) 2617 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2618 2619 /* 2620 * Don't let optional prefaulting of pages make us go 2621 * way below the low water mark of free pages or way 2622 * above high water mark of used pv entries. 2623 */ 2624 if (cnt.v_free_count < cnt.v_free_reserved || 2625 pv_entry_count > pv_entry_high_water) 2626 break; 2627 2628 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2629 ptepindex = addr >> PDRSHIFT; 2630 2631 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2632 if (srcptepaddr == 0) 2633 continue; 2634 2635 if (srcptepaddr & PG_PS) { 2636 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2637 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2638 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2639 } 2640 continue; 2641 } 2642 2643 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2644 if ((srcmpte == NULL) || 2645 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2646 continue; 2647 2648 if (pdnxt > end_addr) 2649 pdnxt = end_addr; 2650 2651 /* 2652 * Have to recheck this before every avtopte() call below 2653 * in case we have blocked and something else used APTDpde. 2654 */ 2655 if (dst_frame != (APTDpde & PG_FRAME)) { 2656 APTDpde = dst_frame | PG_RW | PG_V; 2657 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 2658 } 2659 src_pte = vtopte(addr); 2660 dst_pte = avtopte(addr); 2661 while (addr < pdnxt) { 2662 pt_entry_t ptetemp; 2663 ptetemp = *src_pte; 2664 /* 2665 * we only virtual copy managed pages 2666 */ 2667 if ((ptetemp & PG_MANAGED) != 0) { 2668 /* 2669 * We have to check after allocpte for the 2670 * pte still being around... allocpte can 2671 * block. 2672 */ 2673 dstmpte = pmap_allocpte(dst_pmap, addr); 2674 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2675 /* 2676 * Clear the modified and 2677 * accessed (referenced) bits 2678 * during the copy. 2679 */ 2680 m = PHYS_TO_VM_PAGE(ptetemp); 2681 *dst_pte = ptetemp & ~(PG_M | PG_A); 2682 dst_pmap->pm_stats.resident_count++; 2683 pmap_insert_entry(dst_pmap, addr, 2684 dstmpte, m); 2685 } else { 2686 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2687 } 2688 if (dstmpte->hold_count >= srcmpte->hold_count) 2689 break; 2690 } 2691 addr += PAGE_SIZE; 2692 src_pte++; 2693 dst_pte++; 2694 } 2695 } 2696} 2697 2698#ifdef SMP 2699 2700/* 2701 * pmap_zpi_switchin*() 2702 * 2703 * These functions allow us to avoid doing IPIs alltogether in certain 2704 * temporary page-mapping situations (page zeroing). Instead to deal 2705 * with being preempted and moved onto a different cpu we invalidate 2706 * the page when the scheduler switches us in. This does not occur 2707 * very often so we remain relatively optimal with very little effort. 2708 */ 2709static void 2710pmap_zpi_switchin12(void) 2711{ 2712 invlpg((u_int)CADDR1); 2713 invlpg((u_int)CADDR2); 2714} 2715 2716static void 2717pmap_zpi_switchin2(void) 2718{ 2719 invlpg((u_int)CADDR2); 2720} 2721 2722static void 2723pmap_zpi_switchin3(void) 2724{ 2725 invlpg((u_int)CADDR3); 2726} 2727 2728#endif 2729 2730/* 2731 * pmap_zero_page zeros the specified hardware page by mapping 2732 * the page into KVM and using bzero to clear its contents. 2733 */ 2734void 2735pmap_zero_page(vm_page_t m) 2736{ 2737 vm_offset_t phys; 2738 2739 phys = VM_PAGE_TO_PHYS(m); 2740 if (*CMAP2) 2741 panic("pmap_zero_page: CMAP2 busy"); 2742 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2743#ifdef I386_CPU 2744 invltlb(); 2745#else 2746#ifdef SMP 2747 curthread->td_switchin = pmap_zpi_switchin2; 2748#endif 2749 invlpg((u_int)CADDR2); 2750#endif 2751#if defined(I686_CPU) 2752 if (cpu_class == CPUCLASS_686) 2753 i686_pagezero(CADDR2); 2754 else 2755#endif 2756 bzero(CADDR2, PAGE_SIZE); 2757#ifdef SMP 2758 curthread->td_switchin = NULL; 2759#endif 2760 *CMAP2 = 0; 2761} 2762 2763/* 2764 * pmap_zero_page_area zeros the specified hardware page by mapping 2765 * the page into KVM and using bzero to clear its contents. 2766 * 2767 * off and size may not cover an area beyond a single hardware page. 2768 */ 2769void 2770pmap_zero_page_area(vm_page_t m, int off, int size) 2771{ 2772 vm_offset_t phys; 2773 2774 phys = VM_PAGE_TO_PHYS(m); 2775 if (*CMAP2) 2776 panic("pmap_zero_page: CMAP2 busy"); 2777 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2778#ifdef I386_CPU 2779 invltlb(); 2780#else 2781#ifdef SMP 2782 curthread->td_switchin = pmap_zpi_switchin2; 2783#endif 2784 invlpg((u_int)CADDR2); 2785#endif 2786#if defined(I686_CPU) 2787 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2788 i686_pagezero(CADDR2); 2789 else 2790#endif 2791 bzero((char *)CADDR2 + off, size); 2792#ifdef SMP 2793 curthread->td_switchin = NULL; 2794#endif 2795 *CMAP2 = 0; 2796} 2797 2798/* 2799 * pmap_zero_page_idle zeros the specified hardware page by mapping 2800 * the page into KVM and using bzero to clear its contents. This 2801 * is intended to be called from the vm_pagezero process only and 2802 * outside of Giant. 2803 */ 2804void 2805pmap_zero_page_idle(vm_page_t m) 2806{ 2807 vm_offset_t phys; 2808 2809 phys = VM_PAGE_TO_PHYS(m); 2810 if (*CMAP3) 2811 panic("pmap_zero_page: CMAP3 busy"); 2812 *CMAP3 = PG_V | PG_RW | phys | PG_A | PG_M; 2813#ifdef I386_CPU 2814 invltlb(); 2815#else 2816#ifdef SMP 2817 curthread->td_switchin = pmap_zpi_switchin3; 2818#endif 2819 invlpg((u_int)CADDR3); 2820#endif 2821#if defined(I686_CPU) 2822 if (cpu_class == CPUCLASS_686) 2823 i686_pagezero(CADDR3); 2824 else 2825#endif 2826 bzero(CADDR3, PAGE_SIZE); 2827#ifdef SMP 2828 curthread->td_switchin = NULL; 2829#endif 2830 *CMAP3 = 0; 2831} 2832 2833/* 2834 * pmap_copy_page copies the specified (machine independent) 2835 * page by mapping the page into virtual memory and using 2836 * bcopy to copy the page, one machine dependent page at a 2837 * time. 2838 */ 2839void 2840pmap_copy_page(vm_page_t src, vm_page_t dst) 2841{ 2842 2843 if (*CMAP1) 2844 panic("pmap_copy_page: CMAP1 busy"); 2845 if (*CMAP2) 2846 panic("pmap_copy_page: CMAP2 busy"); 2847 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2848 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2849#ifdef I386_CPU 2850 invltlb(); 2851#else 2852#ifdef SMP 2853 curthread->td_switchin = pmap_zpi_switchin12; 2854#endif 2855 invlpg((u_int)CADDR1); 2856 invlpg((u_int)CADDR2); 2857#endif 2858 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2859#ifdef SMP 2860 curthread->td_switchin = NULL; 2861#endif 2862 *CMAP1 = 0; 2863 *CMAP2 = 0; 2864} 2865 2866 2867/* 2868 * Routine: pmap_pageable 2869 * Function: 2870 * Make the specified pages (by pmap, offset) 2871 * pageable (or not) as requested. 2872 * 2873 * A page which is not pageable may not take 2874 * a fault; therefore, its page table entry 2875 * must remain valid for the duration. 2876 * 2877 * This routine is merely advisory; pmap_enter 2878 * will specify that these pages are to be wired 2879 * down (or not) as appropriate. 2880 */ 2881void 2882pmap_pageable(pmap, sva, eva, pageable) 2883 pmap_t pmap; 2884 vm_offset_t sva, eva; 2885 boolean_t pageable; 2886{ 2887} 2888 2889/* 2890 * Returns true if the pmap's pv is one of the first 2891 * 16 pvs linked to from this page. This count may 2892 * be changed upwards or downwards in the future; it 2893 * is only necessary that true be returned for a small 2894 * subset of pmaps for proper page aging. 2895 */ 2896boolean_t 2897pmap_page_exists_quick(pmap, m) 2898 pmap_t pmap; 2899 vm_page_t m; 2900{ 2901 pv_entry_t pv; 2902 int loops = 0; 2903 int s; 2904 2905 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2906 return FALSE; 2907 2908 s = splvm(); 2909 2910 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2911 if (pv->pv_pmap == pmap) { 2912 splx(s); 2913 return TRUE; 2914 } 2915 loops++; 2916 if (loops >= 16) 2917 break; 2918 } 2919 splx(s); 2920 return (FALSE); 2921} 2922 2923#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2924/* 2925 * Remove all pages from specified address space 2926 * this aids process exit speeds. Also, this code 2927 * is special cased for current process only, but 2928 * can have the more generic (and slightly slower) 2929 * mode enabled. This is much faster than pmap_remove 2930 * in the case of running down an entire address space. 2931 */ 2932void 2933pmap_remove_pages(pmap, sva, eva) 2934 pmap_t pmap; 2935 vm_offset_t sva, eva; 2936{ 2937 pt_entry_t *pte, tpte; 2938 vm_page_t m; 2939 pv_entry_t pv, npv; 2940 int s; 2941 2942#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2943 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2944 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2945 return; 2946 } 2947#endif 2948 2949 s = splvm(); 2950 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2951 2952 if (pv->pv_va >= eva || pv->pv_va < sva) { 2953 npv = TAILQ_NEXT(pv, pv_plist); 2954 continue; 2955 } 2956 2957#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2958 pte = vtopte(pv->pv_va); 2959#else 2960 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2961#endif 2962 tpte = *pte; 2963 2964 if (tpte == 0) { 2965 printf("TPTE at %p IS ZERO @ VA %08x\n", 2966 pte, pv->pv_va); 2967 panic("bad pte"); 2968 } 2969 2970/* 2971 * We cannot remove wired pages from a process' mapping at this time 2972 */ 2973 if (tpte & PG_W) { 2974 npv = TAILQ_NEXT(pv, pv_plist); 2975 continue; 2976 } 2977 2978 m = PHYS_TO_VM_PAGE(tpte); 2979 KASSERT(m->phys_addr == (tpte & PG_FRAME), 2980 ("vm_page_t %p phys_addr mismatch %08x %08x", 2981 m, m->phys_addr, tpte)); 2982 2983 KASSERT(m < &vm_page_array[vm_page_array_size], 2984 ("pmap_remove_pages: bad tpte %x", tpte)); 2985 2986 pv->pv_pmap->pm_stats.resident_count--; 2987 2988 *pte = 0; 2989 2990 /* 2991 * Update the vm_page_t clean and reference bits. 2992 */ 2993 if (tpte & PG_M) { 2994 vm_page_dirty(m); 2995 } 2996 2997 npv = TAILQ_NEXT(pv, pv_plist); 2998 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 2999 3000 m->md.pv_list_count--; 3001 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3002 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 3003 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 3004 } 3005 3006 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 3007 free_pv_entry(pv); 3008 } 3009 splx(s); 3010 pmap_invalidate_all(pmap); 3011} 3012 3013/* 3014 * pmap_testbit tests bits in pte's 3015 * note that the testbit/changebit routines are inline, 3016 * and a lot of things compile-time evaluate. 3017 */ 3018static boolean_t 3019pmap_testbit(m, bit) 3020 vm_page_t m; 3021 int bit; 3022{ 3023 pv_entry_t pv; 3024 pt_entry_t *pte; 3025 int s; 3026 3027 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3028 return FALSE; 3029 3030 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 3031 return FALSE; 3032 3033 s = splvm(); 3034 3035 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3036 /* 3037 * if the bit being tested is the modified bit, then 3038 * mark clean_map and ptes as never 3039 * modified. 3040 */ 3041 if (bit & (PG_A|PG_M)) { 3042 if (!pmap_track_modified(pv->pv_va)) 3043 continue; 3044 } 3045 3046#if defined(PMAP_DIAGNOSTIC) 3047 if (!pv->pv_pmap) { 3048 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3049 continue; 3050 } 3051#endif 3052 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3053 if (*pte & bit) { 3054 splx(s); 3055 return TRUE; 3056 } 3057 } 3058 splx(s); 3059 return (FALSE); 3060} 3061 3062/* 3063 * this routine is used to modify bits in ptes 3064 */ 3065static __inline void 3066pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3067{ 3068 register pv_entry_t pv; 3069 register pt_entry_t *pte; 3070 int s; 3071 3072 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3073 return; 3074 3075 s = splvm(); 3076 3077 /* 3078 * Loop over all current mappings setting/clearing as appropos If 3079 * setting RO do we need to clear the VAC? 3080 */ 3081 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3082 /* 3083 * don't write protect pager mappings 3084 */ 3085 if (!setem && (bit == PG_RW)) { 3086 if (!pmap_track_modified(pv->pv_va)) 3087 continue; 3088 } 3089 3090#if defined(PMAP_DIAGNOSTIC) 3091 if (!pv->pv_pmap) { 3092 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3093 continue; 3094 } 3095#endif 3096 3097 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3098 3099 if (setem) { 3100 *pte |= bit; 3101 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3102 } else { 3103 pt_entry_t pbits = *pte; 3104 if (pbits & bit) { 3105 if (bit == PG_RW) { 3106 if (pbits & PG_M) { 3107 vm_page_dirty(m); 3108 } 3109 *pte = pbits & ~(PG_M|PG_RW); 3110 } else { 3111 *pte = pbits & ~bit; 3112 } 3113 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3114 } 3115 } 3116 } 3117 splx(s); 3118} 3119 3120/* 3121 * pmap_page_protect: 3122 * 3123 * Lower the permission for all mappings to a given page. 3124 */ 3125void 3126pmap_page_protect(vm_page_t m, vm_prot_t prot) 3127{ 3128 if ((prot & VM_PROT_WRITE) == 0) { 3129 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3130 pmap_changebit(m, PG_RW, FALSE); 3131 } else { 3132 pmap_remove_all(m); 3133 } 3134 } 3135} 3136 3137vm_offset_t 3138pmap_phys_address(ppn) 3139 int ppn; 3140{ 3141 return (i386_ptob(ppn)); 3142} 3143 3144/* 3145 * pmap_ts_referenced: 3146 * 3147 * Return a count of reference bits for a page, clearing those bits. 3148 * It is not necessary for every reference bit to be cleared, but it 3149 * is necessary that 0 only be returned when there are truly no 3150 * reference bits set. 3151 * 3152 * XXX: The exact number of bits to check and clear is a matter that 3153 * should be tested and standardized at some point in the future for 3154 * optimal aging of shared pages. 3155 */ 3156int 3157pmap_ts_referenced(vm_page_t m) 3158{ 3159 register pv_entry_t pv, pvf, pvn; 3160 pt_entry_t *pte; 3161 int s; 3162 int rtval = 0; 3163 3164 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3165 return (rtval); 3166 3167 s = splvm(); 3168 3169 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3170 3171 pvf = pv; 3172 3173 do { 3174 pvn = TAILQ_NEXT(pv, pv_list); 3175 3176 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3177 3178 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3179 3180 if (!pmap_track_modified(pv->pv_va)) 3181 continue; 3182 3183 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3184 3185 if (pte && (*pte & PG_A)) { 3186 *pte &= ~PG_A; 3187 3188 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3189 3190 rtval++; 3191 if (rtval > 4) { 3192 break; 3193 } 3194 } 3195 } while ((pv = pvn) != NULL && pv != pvf); 3196 } 3197 splx(s); 3198 3199 return (rtval); 3200} 3201 3202/* 3203 * pmap_is_modified: 3204 * 3205 * Return whether or not the specified physical page was modified 3206 * in any physical maps. 3207 */ 3208boolean_t 3209pmap_is_modified(vm_page_t m) 3210{ 3211 return pmap_testbit(m, PG_M); 3212} 3213 3214/* 3215 * Clear the modify bits on the specified physical page. 3216 */ 3217void 3218pmap_clear_modify(vm_page_t m) 3219{ 3220 pmap_changebit(m, PG_M, FALSE); 3221} 3222 3223/* 3224 * pmap_clear_reference: 3225 * 3226 * Clear the reference bit on the specified physical page. 3227 */ 3228void 3229pmap_clear_reference(vm_page_t m) 3230{ 3231 pmap_changebit(m, PG_A, FALSE); 3232} 3233 3234/* 3235 * Miscellaneous support routines follow 3236 */ 3237 3238static void 3239i386_protection_init() 3240{ 3241 register int *kp, prot; 3242 3243 kp = protection_codes; 3244 for (prot = 0; prot < 8; prot++) { 3245 switch (prot) { 3246 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3247 /* 3248 * Read access is also 0. There isn't any execute bit, 3249 * so just make it readable. 3250 */ 3251 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3252 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3253 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3254 *kp++ = 0; 3255 break; 3256 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3257 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3258 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3259 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3260 *kp++ = PG_RW; 3261 break; 3262 } 3263 } 3264} 3265 3266/* 3267 * Map a set of physical memory pages into the kernel virtual 3268 * address space. Return a pointer to where it is mapped. This 3269 * routine is intended to be used for mapping device memory, 3270 * NOT real memory. 3271 */ 3272void * 3273pmap_mapdev(pa, size) 3274 vm_offset_t pa; 3275 vm_size_t size; 3276{ 3277 vm_offset_t va, tmpva, offset; 3278 pt_entry_t *pte; 3279 3280 offset = pa & PAGE_MASK; 3281 size = roundup(offset + size, PAGE_SIZE); 3282 3283 GIANT_REQUIRED; 3284 3285 va = kmem_alloc_pageable(kernel_map, size); 3286 if (!va) 3287 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3288 3289 pa = pa & PG_FRAME; 3290 for (tmpva = va; size > 0; ) { 3291 pte = vtopte(tmpva); 3292 *pte = pa | PG_RW | PG_V | pgeflag; 3293 size -= PAGE_SIZE; 3294 tmpva += PAGE_SIZE; 3295 pa += PAGE_SIZE; 3296 } 3297 pmap_invalidate_range(kernel_pmap, va, tmpva); 3298 return ((void *)(va + offset)); 3299} 3300 3301void 3302pmap_unmapdev(va, size) 3303 vm_offset_t va; 3304 vm_size_t size; 3305{ 3306 vm_offset_t base, offset, tmpva; 3307 pt_entry_t *pte; 3308 3309 base = va & PG_FRAME; 3310 offset = va & PAGE_MASK; 3311 size = roundup(offset + size, PAGE_SIZE); 3312 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE) { 3313 pte = vtopte(tmpva); 3314 *pte = 0; 3315 } 3316 pmap_invalidate_range(kernel_pmap, va, tmpva); 3317 kmem_free(kernel_map, base, size); 3318} 3319 3320/* 3321 * perform the pmap work for mincore 3322 */ 3323int 3324pmap_mincore(pmap, addr) 3325 pmap_t pmap; 3326 vm_offset_t addr; 3327{ 3328 pt_entry_t *ptep, pte; 3329 vm_page_t m; 3330 int val = 0; 3331 3332 ptep = pmap_pte(pmap, addr); 3333 if (ptep == 0) { 3334 return 0; 3335 } 3336 3337 if ((pte = *ptep) != 0) { 3338 vm_offset_t pa; 3339 3340 val = MINCORE_INCORE; 3341 if ((pte & PG_MANAGED) == 0) 3342 return val; 3343 3344 pa = pte & PG_FRAME; 3345 3346 m = PHYS_TO_VM_PAGE(pa); 3347 3348 /* 3349 * Modified by us 3350 */ 3351 if (pte & PG_M) 3352 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3353 /* 3354 * Modified by someone 3355 */ 3356 else if (m->dirty || pmap_is_modified(m)) 3357 val |= MINCORE_MODIFIED_OTHER; 3358 /* 3359 * Referenced by us 3360 */ 3361 if (pte & PG_A) 3362 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3363 3364 /* 3365 * Referenced by someone 3366 */ 3367 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3368 val |= MINCORE_REFERENCED_OTHER; 3369 vm_page_flag_set(m, PG_REFERENCED); 3370 } 3371 } 3372 return val; 3373} 3374 3375void 3376pmap_activate(struct thread *td) 3377{ 3378 struct proc *p = td->td_proc; 3379 pmap_t pmap; 3380 u_int32_t cr3; 3381 3382 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3383#if defined(SMP) 3384 pmap->pm_active |= PCPU_GET(cpumask); 3385#else 3386 pmap->pm_active |= 1; 3387#endif 3388#if defined(SWTCH_OPTIM_STATS) 3389 tlb_flush_count++; 3390#endif 3391 cr3 = vtophys(pmap->pm_pdir); 3392 /* XXXKSE this is wrong. 3393 * pmap_activate is for the current thread on the current cpu 3394 */ 3395 if (p->p_flag & P_KSES) { 3396 /* Make sure all other cr3 entries are updated. */ 3397 /* what if they are running? XXXKSE (maybe abort them) */ 3398 FOREACH_THREAD_IN_PROC(p, td) { 3399 td->td_pcb->pcb_cr3 = cr3; 3400 } 3401 } else { 3402 td->td_pcb->pcb_cr3 = cr3; 3403 } 3404 load_cr3(cr3); 3405} 3406 3407vm_offset_t 3408pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3409{ 3410 3411 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3412 return addr; 3413 } 3414 3415 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3416 return addr; 3417} 3418 3419 3420#if defined(PMAP_DEBUG) 3421pmap_pid_dump(int pid) 3422{ 3423 pmap_t pmap; 3424 struct proc *p; 3425 int npte = 0; 3426 int index; 3427 3428 sx_slock(&allproc_lock); 3429 LIST_FOREACH(p, &allproc, p_list) { 3430 if (p->p_pid != pid) 3431 continue; 3432 3433 if (p->p_vmspace) { 3434 int i,j; 3435 index = 0; 3436 pmap = vmspace_pmap(p->p_vmspace); 3437 for (i = 0; i < NPDEPG; i++) { 3438 pd_entry_t *pde; 3439 pt_entry_t *pte; 3440 vm_offset_t base = i << PDRSHIFT; 3441 3442 pde = &pmap->pm_pdir[i]; 3443 if (pde && pmap_pde_v(pde)) { 3444 for (j = 0; j < NPTEPG; j++) { 3445 vm_offset_t va = base + (j << PAGE_SHIFT); 3446 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3447 if (index) { 3448 index = 0; 3449 printf("\n"); 3450 } 3451 sx_sunlock(&allproc_lock); 3452 return npte; 3453 } 3454 pte = pmap_pte_quick(pmap, va); 3455 if (pte && pmap_pte_v(pte)) { 3456 pt_entry_t pa; 3457 vm_page_t m; 3458 pa = *pte; 3459 m = PHYS_TO_VM_PAGE(pa); 3460 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3461 va, pa, m->hold_count, m->wire_count, m->flags); 3462 npte++; 3463 index++; 3464 if (index >= 2) { 3465 index = 0; 3466 printf("\n"); 3467 } else { 3468 printf(" "); 3469 } 3470 } 3471 } 3472 } 3473 } 3474 } 3475 } 3476 sx_sunlock(&allproc_lock); 3477 return npte; 3478} 3479#endif 3480 3481#if defined(DEBUG) 3482 3483static void pads(pmap_t pm); 3484void pmap_pvdump(vm_offset_t pa); 3485 3486/* print address space of pmap*/ 3487static void 3488pads(pm) 3489 pmap_t pm; 3490{ 3491 int i, j; 3492 vm_offset_t va; 3493 pt_entry_t *ptep; 3494 3495 if (pm == kernel_pmap) 3496 return; 3497 for (i = 0; i < NPDEPG; i++) 3498 if (pm->pm_pdir[i]) 3499 for (j = 0; j < NPTEPG; j++) { 3500 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3501 if (pm == kernel_pmap && va < KERNBASE) 3502 continue; 3503 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3504 continue; 3505 ptep = pmap_pte_quick(pm, va); 3506 if (pmap_pte_v(ptep)) 3507 printf("%x:%x ", va, *ptep); 3508 }; 3509 3510} 3511 3512void 3513pmap_pvdump(pa) 3514 vm_offset_t pa; 3515{ 3516 pv_entry_t pv; 3517 vm_page_t m; 3518 3519 printf("pa %x", pa); 3520 m = PHYS_TO_VM_PAGE(pa); 3521 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3522 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3523 pads(pv->pv_pmap); 3524 } 3525 printf(" "); 3526} 3527#endif 3528