pmap.c revision 99987
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 99987 2002-07-14 20:24:40Z 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 endva = KERNBASE + KERNend; 447 while (va < endva) { 448 pte = vtopte(va); 449 if (*pte) 450 *pte |= pgeflag; 451 va += PAGE_SIZE; 452 } 453 invltlb(); /* Insurance */ 454 } 455 /* 456 * We do not need to broadcast the invltlb here, because 457 * each AP does it the moment it is released from the boot 458 * lock. See ap_init(). 459 */ 460 } 461} 462 463void * 464pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait) 465{ 466 *flags = UMA_SLAB_PRIV; 467 return (void *)kmem_alloc(kernel_map, bytes); 468} 469 470/* 471 * Initialize the pmap module. 472 * Called by vm_init, to initialize any structures that the pmap 473 * system needs to map virtual memory. 474 * pmap_init has been enhanced to support in a fairly consistant 475 * way, discontiguous physical memory. 476 */ 477void 478pmap_init(phys_start, phys_end) 479 vm_offset_t phys_start, phys_end; 480{ 481 int i; 482 int initial_pvs; 483 484 /* 485 * object for kernel page table pages 486 */ 487 kptobj = vm_object_allocate(OBJT_DEFAULT, NKPDE); 488 489 /* 490 * Allocate memory for random pmap data structures. Includes the 491 * pv_head_table. 492 */ 493 494 for(i = 0; i < vm_page_array_size; i++) { 495 vm_page_t m; 496 497 m = &vm_page_array[i]; 498 TAILQ_INIT(&m->md.pv_list); 499 m->md.pv_list_count = 0; 500 } 501 502 /* 503 * init the pv free list 504 */ 505 initial_pvs = vm_page_array_size; 506 if (initial_pvs < MINPV) 507 initial_pvs = MINPV; 508 pvzone = uma_zcreate("PV ENTRY", sizeof (struct pv_entry), NULL, NULL, 509 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM); 510 uma_zone_set_allocf(pvzone, pmap_allocf); 511 uma_prealloc(pvzone, initial_pvs); 512 513 /* 514 * Now it is safe to enable pv_table recording. 515 */ 516 pmap_initialized = TRUE; 517} 518 519/* 520 * Initialize the address space (zone) for the pv_entries. Set a 521 * high water mark so that the system can recover from excessive 522 * numbers of pv entries. 523 */ 524void 525pmap_init2() 526{ 527 int shpgperproc = PMAP_SHPGPERPROC; 528 529 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc); 530 pv_entry_max = shpgperproc * maxproc + vm_page_array_size; 531 TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max); 532 pv_entry_high_water = 9 * (pv_entry_max / 10); 533 uma_zone_set_obj(pvzone, &pvzone_obj, pv_entry_max); 534} 535 536 537/*************************************************** 538 * Low level helper routines..... 539 ***************************************************/ 540 541#if defined(PMAP_DIAGNOSTIC) 542 543/* 544 * This code checks for non-writeable/modified pages. 545 * This should be an invalid condition. 546 */ 547static int 548pmap_nw_modified(pt_entry_t ptea) 549{ 550 int pte; 551 552 pte = (int) ptea; 553 554 if ((pte & (PG_M|PG_RW)) == PG_M) 555 return 1; 556 else 557 return 0; 558} 559#endif 560 561 562/* 563 * this routine defines the region(s) of memory that should 564 * not be tested for the modified bit. 565 */ 566static PMAP_INLINE int 567pmap_track_modified(vm_offset_t va) 568{ 569 if ((va < kmi.clean_sva) || (va >= kmi.clean_eva)) 570 return 1; 571 else 572 return 0; 573} 574 575#ifdef I386_CPU 576/* 577 * i386 only has "invalidate everything" and no SMP to worry about. 578 */ 579PMAP_INLINE void 580pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 581{ 582 583 if (pmap == kernel_pmap || pmap->pm_active) 584 invltlb(); 585} 586 587PMAP_INLINE void 588pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 589{ 590 591 if (pmap == kernel_pmap || pmap->pm_active) 592 invltlb(); 593} 594 595PMAP_INLINE void 596pmap_invalidate_all(pmap_t pmap) 597{ 598 599 if (pmap == kernel_pmap || pmap->pm_active) 600 invltlb(); 601} 602#else /* !I386_CPU */ 603#ifdef SMP 604/* 605 * For SMP, these functions have to use the IPI mechanism for coherence. 606 */ 607void 608pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 609{ 610 u_int cpumask; 611 u_int other_cpus; 612 613 critical_enter(); 614 /* 615 * We need to disable interrupt preemption but MUST NOT have 616 * interrupts disabled here. 617 * XXX we may need to hold schedlock to get a coherent pm_active 618 */ 619 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 620 invlpg(va); 621 smp_invlpg(va); 622 } else { 623 cpumask = PCPU_GET(cpumask); 624 other_cpus = PCPU_GET(other_cpus); 625 if (pmap->pm_active & cpumask) 626 invlpg(va); 627 if (pmap->pm_active & other_cpus) 628 smp_masked_invlpg(pmap->pm_active & other_cpus, va); 629 } 630 critical_exit(); 631} 632 633void 634pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 635{ 636 u_int cpumask; 637 u_int other_cpus; 638 vm_offset_t addr; 639 640 critical_enter(); 641 /* 642 * We need to disable interrupt preemption but MUST NOT have 643 * interrupts disabled here. 644 * XXX we may need to hold schedlock to get a coherent pm_active 645 */ 646 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 647 for (addr = sva; addr < eva; addr += PAGE_SIZE) 648 invlpg(addr); 649 smp_invlpg_range(sva, eva); 650 } else { 651 cpumask = PCPU_GET(cpumask); 652 other_cpus = PCPU_GET(other_cpus); 653 if (pmap->pm_active & cpumask) 654 for (addr = sva; addr < eva; addr += PAGE_SIZE) 655 invlpg(addr); 656 if (pmap->pm_active & other_cpus) 657 smp_masked_invlpg_range(pmap->pm_active & other_cpus, 658 sva, eva); 659 } 660 critical_exit(); 661} 662 663void 664pmap_invalidate_all(pmap_t pmap) 665{ 666 u_int cpumask; 667 u_int other_cpus; 668 669 critical_enter(); 670 /* 671 * We need to disable interrupt preemption but MUST NOT have 672 * interrupts disabled here. 673 * XXX we may need to hold schedlock to get a coherent pm_active 674 */ 675 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 676 invltlb(); 677 smp_invltlb(); 678 } else { 679 cpumask = PCPU_GET(cpumask); 680 other_cpus = PCPU_GET(other_cpus); 681 if (pmap->pm_active & cpumask) 682 invltlb(); 683 if (pmap->pm_active & other_cpus) 684 smp_masked_invltlb(pmap->pm_active & other_cpus); 685 } 686 critical_exit(); 687} 688#else /* !SMP */ 689/* 690 * Normal, non-SMP, 486+ invalidation functions. 691 * We inline these within pmap.c for speed. 692 */ 693PMAP_INLINE void 694pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 695{ 696 697 if (pmap == kernel_pmap || pmap->pm_active) 698 invlpg(va); 699} 700 701PMAP_INLINE void 702pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 703{ 704 vm_offset_t addr; 705 706 if (pmap == kernel_pmap || pmap->pm_active) 707 for (addr = sva; addr < eva; addr += PAGE_SIZE) 708 invlpg(addr); 709} 710 711PMAP_INLINE void 712pmap_invalidate_all(pmap_t pmap) 713{ 714 715 if (pmap == kernel_pmap || pmap->pm_active) 716 invltlb(); 717} 718#endif /* !SMP */ 719#endif /* !I386_CPU */ 720 721/* 722 * Return an address which is the base of the Virtual mapping of 723 * all the PTEs for the given pmap. Note this doesn't say that 724 * all the PTEs will be present or that the pages there are valid. 725 * The PTEs are made available by the recursive mapping trick. 726 * It will map in the alternate PTE space if needed. 727 */ 728static pt_entry_t * 729get_ptbase(pmap) 730 pmap_t pmap; 731{ 732 pd_entry_t frame; 733 734 /* are we current address space or kernel? */ 735 if (pmap == kernel_pmap) 736 return PTmap; 737 frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 738 if (frame == (PTDpde & PG_FRAME)) 739 return PTmap; 740 /* otherwise, we are alternate address space */ 741 if (frame != (APTDpde & PG_FRAME)) { 742 APTDpde = (pd_entry_t) (frame | PG_RW | PG_V); 743 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 744 } 745 return APTmap; 746} 747 748/* 749 * Super fast pmap_pte routine best used when scanning 750 * the pv lists. This eliminates many coarse-grained 751 * invltlb calls. Note that many of the pv list 752 * scans are across different pmaps. It is very wasteful 753 * to do an entire invltlb for checking a single mapping. 754 */ 755 756static pt_entry_t * 757pmap_pte_quick(pmap, va) 758 register pmap_t pmap; 759 vm_offset_t va; 760{ 761 pd_entry_t pde, newpf; 762 pde = pmap->pm_pdir[va >> PDRSHIFT]; 763 if (pde != 0) { 764 pd_entry_t frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 765 unsigned index = i386_btop(va); 766 /* are we current address space or kernel? */ 767 if (pmap == kernel_pmap || frame == (PTDpde & PG_FRAME)) 768 return PTmap + index; 769 newpf = pde & PG_FRAME; 770 if (((*PMAP1) & PG_FRAME) != newpf) { 771 *PMAP1 = newpf | PG_RW | PG_V; 772 pmap_invalidate_page(kernel_pmap, (vm_offset_t)PADDR1); 773 } 774 return PADDR1 + (index & (NPTEPG - 1)); 775 } 776 return (0); 777} 778 779/* 780 * Routine: pmap_extract 781 * Function: 782 * Extract the physical page address associated 783 * with the given map/virtual_address pair. 784 */ 785vm_offset_t 786pmap_extract(pmap, va) 787 register pmap_t pmap; 788 vm_offset_t va; 789{ 790 vm_offset_t rtval; /* XXX FIXME */ 791 vm_offset_t pdirindex; 792 793 if (pmap == 0) 794 return 0; 795 pdirindex = va >> PDRSHIFT; 796 rtval = pmap->pm_pdir[pdirindex]; 797 if (rtval != 0) { 798 pt_entry_t *pte; 799 if ((rtval & PG_PS) != 0) { 800 rtval &= ~(NBPDR - 1); 801 rtval |= va & (NBPDR - 1); 802 return rtval; 803 } 804 pte = get_ptbase(pmap) + i386_btop(va); 805 rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); 806 return rtval; 807 } 808 return 0; 809 810} 811 812/*************************************************** 813 * Low level mapping routines..... 814 ***************************************************/ 815 816/* 817 * Add a wired page to the kva. 818 * Note: not SMP coherent. 819 */ 820PMAP_INLINE void 821pmap_kenter(vm_offset_t va, vm_offset_t pa) 822{ 823 pt_entry_t *pte; 824 825 pte = vtopte(va); 826 *pte = pa | PG_RW | PG_V | pgeflag; 827} 828 829/* 830 * Remove a page from the kernel pagetables. 831 * Note: not SMP coherent. 832 */ 833PMAP_INLINE void 834pmap_kremove(vm_offset_t va) 835{ 836 pt_entry_t *pte; 837 838 pte = vtopte(va); 839 *pte = 0; 840} 841 842/* 843 * Used to map a range of physical addresses into kernel 844 * virtual address space. 845 * 846 * The value passed in '*virt' is a suggested virtual address for 847 * the mapping. Architectures which can support a direct-mapped 848 * physical to virtual region can return the appropriate address 849 * within that region, leaving '*virt' unchanged. Other 850 * architectures should map the pages starting at '*virt' and 851 * update '*virt' with the first usable address after the mapped 852 * region. 853 */ 854vm_offset_t 855pmap_map(vm_offset_t *virt, vm_offset_t start, vm_offset_t end, int prot) 856{ 857 vm_offset_t va, sva; 858 859 va = sva = *virt; 860 while (start < end) { 861 pmap_kenter(va, start); 862 va += PAGE_SIZE; 863 start += PAGE_SIZE; 864 } 865 pmap_invalidate_range(kernel_pmap, sva, va); 866 *virt = va; 867 return (sva); 868} 869 870 871/* 872 * Add a list of wired pages to the kva 873 * this routine is only used for temporary 874 * kernel mappings that do not need to have 875 * page modification or references recorded. 876 * Note that old mappings are simply written 877 * over. The page *must* be wired. 878 * Note: SMP coherent. Uses a ranged shootdown IPI. 879 */ 880void 881pmap_qenter(vm_offset_t sva, vm_page_t *m, int count) 882{ 883 vm_offset_t va; 884 885 va = sva; 886 while (count-- > 0) { 887 pmap_kenter(va, VM_PAGE_TO_PHYS(*m)); 888 va += PAGE_SIZE; 889 m++; 890 } 891 pmap_invalidate_range(kernel_pmap, sva, va); 892} 893 894/* 895 * This routine tears out page mappings from the 896 * kernel -- it is meant only for temporary mappings. 897 * Note: SMP coherent. Uses a ranged shootdown IPI. 898 */ 899void 900pmap_qremove(vm_offset_t sva, int count) 901{ 902 vm_offset_t va; 903 904 va = sva; 905 while (count-- > 0) { 906 pmap_kremove(va); 907 va += PAGE_SIZE; 908 } 909 pmap_invalidate_range(kernel_pmap, sva, va); 910} 911 912static vm_page_t 913pmap_page_lookup(vm_object_t object, vm_pindex_t pindex) 914{ 915 vm_page_t m; 916 917retry: 918 m = vm_page_lookup(object, pindex); 919 if (m && vm_page_sleep_busy(m, FALSE, "pplookp")) 920 goto retry; 921 return m; 922} 923 924/* 925 * Create the kernel stack (including pcb for i386) for a new thread. 926 * This routine directly affects the fork perf for a process and 927 * create performance for a thread. 928 */ 929void 930pmap_new_thread(struct thread *td) 931{ 932 int i; 933 vm_page_t ma[KSTACK_PAGES]; 934 vm_object_t ksobj; 935 vm_page_t m; 936 vm_offset_t ks; 937 938 /* 939 * allocate object for the kstack 940 */ 941 ksobj = vm_object_allocate(OBJT_DEFAULT, KSTACK_PAGES); 942 td->td_kstack_obj = ksobj; 943 944 /* get a kernel virtual address for the kstack for this thread */ 945#ifdef KSTACK_GUARD 946 ks = kmem_alloc_nofault(kernel_map, (KSTACK_PAGES + 1) * PAGE_SIZE); 947 if (ks == 0) 948 panic("pmap_new_thread: kstack allocation failed"); 949 if (*vtopte(ks) != 0) 950 pmap_qremove(ks, 1); 951 ks += PAGE_SIZE; 952 td->td_kstack = ks; 953#else 954 /* get a kernel virtual address for the kstack for this thread */ 955 ks = kmem_alloc_nofault(kernel_map, KSTACK_PAGES * PAGE_SIZE); 956 if (ks == 0) 957 panic("pmap_new_thread: kstack allocation failed"); 958 td->td_kstack = ks; 959#endif 960 /* 961 * For the length of the stack, link in a real page of ram for each 962 * page of stack. 963 */ 964 for (i = 0; i < KSTACK_PAGES; i++) { 965 /* 966 * Get a kernel stack page 967 */ 968 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 969 ma[i] = m; 970 971 /* 972 * Wire the page 973 */ 974 m->wire_count++; 975 cnt.v_wire_count++; 976 977 vm_page_wakeup(m); 978 vm_page_flag_clear(m, PG_ZERO); 979 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 980 m->valid = VM_PAGE_BITS_ALL; 981 } 982 pmap_qenter(ks, ma, KSTACK_PAGES); 983} 984 985/* 986 * Dispose the kernel stack for a thread that has exited. 987 * This routine directly impacts the exit perf of a process and thread. 988 */ 989void 990pmap_dispose_thread(td) 991 struct thread *td; 992{ 993 int i; 994 vm_object_t ksobj; 995 vm_offset_t ks; 996 vm_page_t m; 997 998 ksobj = td->td_kstack_obj; 999 ks = td->td_kstack; 1000 pmap_qremove(ks, KSTACK_PAGES); 1001 for (i = 0; i < KSTACK_PAGES; i++) { 1002 m = vm_page_lookup(ksobj, i); 1003 if (m == NULL) 1004 panic("pmap_dispose_thread: kstack already missing?"); 1005 vm_page_lock_queues(); 1006 vm_page_busy(m); 1007 vm_page_unwire(m, 0); 1008 vm_page_free(m); 1009 vm_page_unlock_queues(); 1010 } 1011 /* 1012 * Free the space that this stack was mapped to in the kernel 1013 * address map. 1014 */ 1015#ifdef KSTACK_GUARD 1016 kmem_free(kernel_map, ks - PAGE_SIZE, (KSTACK_PAGES + 1) * PAGE_SIZE); 1017#else 1018 kmem_free(kernel_map, ks, KSTACK_PAGES * PAGE_SIZE); 1019#endif 1020 vm_object_deallocate(ksobj); 1021} 1022 1023/* 1024 * Allow the Kernel stack for a thread to be prejudicially paged out. 1025 */ 1026void 1027pmap_swapout_thread(td) 1028 struct thread *td; 1029{ 1030 int i; 1031 vm_object_t ksobj; 1032 vm_offset_t ks; 1033 vm_page_t m; 1034 1035 ksobj = td->td_kstack_obj; 1036 ks = td->td_kstack; 1037 pmap_qremove(ks, KSTACK_PAGES); 1038 for (i = 0; i < KSTACK_PAGES; i++) { 1039 m = vm_page_lookup(ksobj, i); 1040 if (m == NULL) 1041 panic("pmap_swapout_thread: kstack already missing?"); 1042 vm_page_lock_queues(); 1043 vm_page_dirty(m); 1044 vm_page_unwire(m, 0); 1045 vm_page_unlock_queues(); 1046 } 1047} 1048 1049/* 1050 * Bring the kernel stack for a specified thread back in. 1051 */ 1052void 1053pmap_swapin_thread(td) 1054 struct thread *td; 1055{ 1056 int i, rv; 1057 vm_page_t ma[KSTACK_PAGES]; 1058 vm_object_t ksobj; 1059 vm_offset_t ks; 1060 vm_page_t m; 1061 1062 ksobj = td->td_kstack_obj; 1063 ks = td->td_kstack; 1064 for (i = 0; i < KSTACK_PAGES; i++) { 1065 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1066 if (m->valid != VM_PAGE_BITS_ALL) { 1067 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1068 if (rv != VM_PAGER_OK) 1069 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1070 m = vm_page_lookup(ksobj, i); 1071 m->valid = VM_PAGE_BITS_ALL; 1072 } 1073 ma[i] = m; 1074 vm_page_lock_queues(); 1075 vm_page_wire(m); 1076 vm_page_wakeup(m); 1077 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 1078 vm_page_unlock_queues(); 1079 } 1080 pmap_qenter(ks, ma, KSTACK_PAGES); 1081} 1082 1083/*************************************************** 1084 * Page table page management routines..... 1085 ***************************************************/ 1086 1087/* 1088 * This routine unholds page table pages, and if the hold count 1089 * drops to zero, then it decrements the wire count. 1090 */ 1091static int 1092_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1093{ 1094 1095 while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) 1096 ; 1097 1098 if (m->hold_count == 0) { 1099 vm_offset_t pteva; 1100 /* 1101 * unmap the page table page 1102 */ 1103 pmap->pm_pdir[m->pindex] = 0; 1104 --pmap->pm_stats.resident_count; 1105 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1106 (PTDpde & PG_FRAME)) { 1107 /* 1108 * Do a invltlb to make the invalidated mapping 1109 * take effect immediately. 1110 */ 1111 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); 1112 pmap_invalidate_page(pmap, pteva); 1113 } 1114 1115 if (pmap->pm_ptphint == m) 1116 pmap->pm_ptphint = NULL; 1117 1118 /* 1119 * If the page is finally unwired, simply free it. 1120 */ 1121 --m->wire_count; 1122 if (m->wire_count == 0) { 1123 1124 vm_page_flash(m); 1125 vm_page_busy(m); 1126 vm_page_free_zero(m); 1127 --cnt.v_wire_count; 1128 } 1129 return 1; 1130 } 1131 return 0; 1132} 1133 1134static PMAP_INLINE int 1135pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1136{ 1137 vm_page_unhold(m); 1138 if (m->hold_count == 0) 1139 return _pmap_unwire_pte_hold(pmap, m); 1140 else 1141 return 0; 1142} 1143 1144/* 1145 * After removing a page table entry, this routine is used to 1146 * conditionally free the page, and manage the hold/wire counts. 1147 */ 1148static int 1149pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1150{ 1151 unsigned ptepindex; 1152 if (va >= VM_MAXUSER_ADDRESS) 1153 return 0; 1154 1155 if (mpte == NULL) { 1156 ptepindex = (va >> PDRSHIFT); 1157 if (pmap->pm_ptphint && 1158 (pmap->pm_ptphint->pindex == ptepindex)) { 1159 mpte = pmap->pm_ptphint; 1160 } else { 1161 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1162 pmap->pm_ptphint = mpte; 1163 } 1164 } 1165 1166 return pmap_unwire_pte_hold(pmap, mpte); 1167} 1168 1169void 1170pmap_pinit0(pmap) 1171 struct pmap *pmap; 1172{ 1173 pmap->pm_pdir = 1174 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1175 pmap_kenter((vm_offset_t)pmap->pm_pdir, (vm_offset_t)IdlePTD); 1176#ifndef I386_CPU 1177 invlpg((vm_offset_t)pmap->pm_pdir); 1178#else 1179 invltlb(); 1180#endif 1181 pmap->pm_ptphint = NULL; 1182 pmap->pm_active = 0; 1183 TAILQ_INIT(&pmap->pm_pvlist); 1184 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1185 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1186} 1187 1188/* 1189 * Initialize a preallocated and zeroed pmap structure, 1190 * such as one in a vmspace structure. 1191 */ 1192void 1193pmap_pinit(pmap) 1194 register struct pmap *pmap; 1195{ 1196 vm_page_t ptdpg; 1197 1198 /* 1199 * No need to allocate page table space yet but we do need a valid 1200 * page directory table. 1201 */ 1202 if (pmap->pm_pdir == NULL) 1203 pmap->pm_pdir = 1204 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1205 1206 /* 1207 * allocate object for the ptes 1208 */ 1209 if (pmap->pm_pteobj == NULL) 1210 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1211 1212 /* 1213 * allocate the page directory page 1214 */ 1215 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1216 VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1217 1218 ptdpg->wire_count = 1; 1219 ++cnt.v_wire_count; 1220 1221 1222 vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/ 1223 ptdpg->valid = VM_PAGE_BITS_ALL; 1224 1225 pmap_qenter((vm_offset_t) pmap->pm_pdir, &ptdpg, 1); 1226 if ((ptdpg->flags & PG_ZERO) == 0) 1227 bzero(pmap->pm_pdir, PAGE_SIZE); 1228 1229 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1230 /* Wire in kernel global address entries. */ 1231 /* XXX copies current process, does not fill in MPPTDI */ 1232 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1233#ifdef SMP 1234 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1235#endif 1236 1237 /* install self-referential address mapping entry */ 1238 pmap->pm_pdir[PTDPTDI] = 1239 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1240 1241 pmap->pm_active = 0; 1242 pmap->pm_ptphint = NULL; 1243 TAILQ_INIT(&pmap->pm_pvlist); 1244 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1245} 1246 1247/* 1248 * Wire in kernel global address entries. To avoid a race condition 1249 * between pmap initialization and pmap_growkernel, this procedure 1250 * should be called after the vmspace is attached to the process 1251 * but before this pmap is activated. 1252 */ 1253void 1254pmap_pinit2(pmap) 1255 struct pmap *pmap; 1256{ 1257 /* XXX: Remove this stub when no longer called */ 1258} 1259 1260static int 1261pmap_release_free_page(pmap_t pmap, vm_page_t p) 1262{ 1263 pd_entry_t *pde = pmap->pm_pdir; 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 if (vm_page_sleep_busy(p, FALSE, "pmaprl")) 1270 return 0; 1271 1272 vm_page_busy(p); 1273 1274 /* 1275 * Remove the page table page from the processes address space. 1276 */ 1277 pde[p->pindex] = 0; 1278 pmap->pm_stats.resident_count--; 1279 1280 if (p->hold_count) { 1281 panic("pmap_release: freeing held page table page"); 1282 } 1283 /* 1284 * Page directory pages need to have the kernel 1285 * stuff cleared, so they can go into the zero queue also. 1286 */ 1287 if (p->pindex == PTDPTDI) { 1288 bzero(pde + KPTDI, nkpt * PTESIZE); 1289#ifdef SMP 1290 pde[MPPTDI] = 0; 1291#endif 1292 pde[APTDPTDI] = 0; 1293 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1294 } 1295 1296 if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex)) 1297 pmap->pm_ptphint = NULL; 1298 1299 p->wire_count--; 1300 cnt.v_wire_count--; 1301 vm_page_free_zero(p); 1302 return 1; 1303} 1304 1305/* 1306 * this routine is called if the page table page is not 1307 * mapped correctly. 1308 */ 1309static vm_page_t 1310_pmap_allocpte(pmap, ptepindex) 1311 pmap_t pmap; 1312 unsigned ptepindex; 1313{ 1314 vm_offset_t pteva, ptepa; /* XXXPA */ 1315 vm_page_t m; 1316 1317 /* 1318 * Find or fabricate a new pagetable page 1319 */ 1320 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1321 VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1322 1323 KASSERT(m->queue == PQ_NONE, 1324 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1325 1326 if (m->wire_count == 0) 1327 cnt.v_wire_count++; 1328 m->wire_count++; 1329 1330 /* 1331 * Increment the hold count for the page table page 1332 * (denoting a new mapping.) 1333 */ 1334 m->hold_count++; 1335 1336 /* 1337 * Map the pagetable page into the process address space, if 1338 * it isn't already there. 1339 */ 1340 1341 pmap->pm_stats.resident_count++; 1342 1343 ptepa = VM_PAGE_TO_PHYS(m); 1344 pmap->pm_pdir[ptepindex] = 1345 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1346 1347 /* 1348 * Set the page table hint 1349 */ 1350 pmap->pm_ptphint = m; 1351 1352 /* 1353 * Try to use the new mapping, but if we cannot, then 1354 * do it with the routine that maps the page explicitly. 1355 */ 1356 if ((m->flags & PG_ZERO) == 0) { 1357 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1358 (PTDpde & PG_FRAME)) { 1359 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1360 bzero((caddr_t) pteva, PAGE_SIZE); 1361 } else { 1362 pmap_zero_page(m); 1363 } 1364 } 1365 1366 m->valid = VM_PAGE_BITS_ALL; 1367 vm_page_flag_clear(m, PG_ZERO); 1368 vm_page_flag_set(m, PG_MAPPED); 1369 vm_page_wakeup(m); 1370 1371 return m; 1372} 1373 1374static vm_page_t 1375pmap_allocpte(pmap_t pmap, vm_offset_t va) 1376{ 1377 unsigned ptepindex; 1378 pd_entry_t ptepa; 1379 vm_page_t m; 1380 1381 /* 1382 * Calculate pagetable page index 1383 */ 1384 ptepindex = va >> PDRSHIFT; 1385 1386 /* 1387 * Get the page directory entry 1388 */ 1389 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1390 1391 /* 1392 * This supports switching from a 4MB page to a 1393 * normal 4K page. 1394 */ 1395 if (ptepa & PG_PS) { 1396 pmap->pm_pdir[ptepindex] = 0; 1397 ptepa = 0; 1398 pmap_invalidate_all(kernel_pmap); 1399 } 1400 1401 /* 1402 * If the page table page is mapped, we just increment the 1403 * hold count, and activate it. 1404 */ 1405 if (ptepa) { 1406 /* 1407 * In order to get the page table page, try the 1408 * hint first. 1409 */ 1410 if (pmap->pm_ptphint && 1411 (pmap->pm_ptphint->pindex == ptepindex)) { 1412 m = pmap->pm_ptphint; 1413 } else { 1414 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1415 pmap->pm_ptphint = m; 1416 } 1417 m->hold_count++; 1418 return m; 1419 } 1420 /* 1421 * Here if the pte page isn't mapped, or if it has been deallocated. 1422 */ 1423 return _pmap_allocpte(pmap, ptepindex); 1424} 1425 1426 1427/*************************************************** 1428* Pmap allocation/deallocation routines. 1429 ***************************************************/ 1430 1431/* 1432 * Release any resources held by the given physical map. 1433 * Called when a pmap initialized by pmap_pinit is being released. 1434 * Should only be called if the map contains no valid mappings. 1435 */ 1436void 1437pmap_release(pmap_t pmap) 1438{ 1439 vm_page_t p,n,ptdpg; 1440 vm_object_t object = pmap->pm_pteobj; 1441 int curgeneration; 1442 1443#if defined(DIAGNOSTIC) 1444 if (object->ref_count != 1) 1445 panic("pmap_release: pteobj reference count != 1"); 1446#endif 1447 1448 ptdpg = NULL; 1449 LIST_REMOVE(pmap, pm_list); 1450retry: 1451 curgeneration = object->generation; 1452 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1453 n = TAILQ_NEXT(p, listq); 1454 if (p->pindex == PTDPTDI) { 1455 ptdpg = p; 1456 continue; 1457 } 1458 while (1) { 1459 if (!pmap_release_free_page(pmap, p) && 1460 (object->generation != curgeneration)) 1461 goto retry; 1462 } 1463 } 1464 1465 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1466 goto retry; 1467} 1468 1469static int 1470kvm_size(SYSCTL_HANDLER_ARGS) 1471{ 1472 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1473 1474 return sysctl_handle_long(oidp, &ksize, 0, req); 1475} 1476SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1477 0, 0, kvm_size, "IU", "Size of KVM"); 1478 1479static int 1480kvm_free(SYSCTL_HANDLER_ARGS) 1481{ 1482 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1483 1484 return sysctl_handle_long(oidp, &kfree, 0, req); 1485} 1486SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1487 0, 0, kvm_free, "IU", "Amount of KVM free"); 1488 1489/* 1490 * grow the number of kernel page table entries, if needed 1491 */ 1492void 1493pmap_growkernel(vm_offset_t addr) 1494{ 1495 struct pmap *pmap; 1496 int s; 1497 vm_offset_t ptppaddr; 1498 vm_page_t nkpg; 1499 pd_entry_t newpdir; 1500 1501 s = splhigh(); 1502 if (kernel_vm_end == 0) { 1503 kernel_vm_end = KERNBASE; 1504 nkpt = 0; 1505 while (pdir_pde(PTD, kernel_vm_end)) { 1506 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1507 nkpt++; 1508 } 1509 } 1510 addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1511 while (kernel_vm_end < addr) { 1512 if (pdir_pde(PTD, kernel_vm_end)) { 1513 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1514 continue; 1515 } 1516 1517 /* 1518 * This index is bogus, but out of the way 1519 */ 1520 nkpg = vm_page_alloc(kptobj, nkpt, VM_ALLOC_SYSTEM); 1521 if (!nkpg) 1522 panic("pmap_growkernel: no memory to grow kernel"); 1523 1524 nkpt++; 1525 1526 vm_page_lock_queues(); 1527 vm_page_wire(nkpg); 1528 vm_page_unlock_queues(); 1529 pmap_zero_page(nkpg); 1530 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1531 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1532 pdir_pde(PTD, kernel_vm_end) = newpdir; 1533 1534 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1535 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1536 } 1537 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1538 } 1539 splx(s); 1540} 1541 1542 1543/*************************************************** 1544 * page management routines. 1545 ***************************************************/ 1546 1547/* 1548 * free the pv_entry back to the free list 1549 */ 1550static PMAP_INLINE void 1551free_pv_entry(pv_entry_t pv) 1552{ 1553 pv_entry_count--; 1554 uma_zfree(pvzone, pv); 1555} 1556 1557/* 1558 * get a new pv_entry, allocating a block from the system 1559 * when needed. 1560 * the memory allocation is performed bypassing the malloc code 1561 * because of the possibility of allocations at interrupt time. 1562 */ 1563static pv_entry_t 1564get_pv_entry(void) 1565{ 1566 pv_entry_count++; 1567 if (pv_entry_high_water && 1568 (pv_entry_count > pv_entry_high_water) && 1569 (pmap_pagedaemon_waken == 0)) { 1570 pmap_pagedaemon_waken = 1; 1571 wakeup (&vm_pages_needed); 1572 } 1573 return uma_zalloc(pvzone, M_NOWAIT); 1574} 1575 1576/* 1577 * This routine is very drastic, but can save the system 1578 * in a pinch. 1579 */ 1580void 1581pmap_collect() 1582{ 1583 int i; 1584 vm_page_t m; 1585 static int warningdone = 0; 1586 1587 if (pmap_pagedaemon_waken == 0) 1588 return; 1589 1590 if (warningdone < 5) { 1591 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1592 warningdone++; 1593 } 1594 1595 for(i = 0; i < vm_page_array_size; i++) { 1596 m = &vm_page_array[i]; 1597 if (m->wire_count || m->hold_count || m->busy || 1598 (m->flags & (PG_BUSY | PG_UNMANAGED))) 1599 continue; 1600 pmap_remove_all(m); 1601 } 1602 pmap_pagedaemon_waken = 0; 1603} 1604 1605 1606/* 1607 * If it is the first entry on the list, it is actually 1608 * in the header and we must copy the following entry up 1609 * to the header. Otherwise we must search the list for 1610 * the entry. In either case we free the now unused entry. 1611 */ 1612 1613static int 1614pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1615{ 1616 pv_entry_t pv; 1617 int rtval; 1618 int s; 1619 1620 s = splvm(); 1621 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1622 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1623 if (pmap == pv->pv_pmap && va == pv->pv_va) 1624 break; 1625 } 1626 } else { 1627 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1628 if (va == pv->pv_va) 1629 break; 1630 } 1631 } 1632 1633 rtval = 0; 1634 if (pv) { 1635 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1636 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1637 m->md.pv_list_count--; 1638 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1639 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1640 1641 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1642 free_pv_entry(pv); 1643 } 1644 1645 splx(s); 1646 return rtval; 1647} 1648 1649/* 1650 * Create a pv entry for page at pa for 1651 * (pmap, va). 1652 */ 1653static void 1654pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1655{ 1656 1657 int s; 1658 pv_entry_t pv; 1659 1660 s = splvm(); 1661 pv = get_pv_entry(); 1662 pv->pv_va = va; 1663 pv->pv_pmap = pmap; 1664 pv->pv_ptem = mpte; 1665 1666 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1667 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1668 m->md.pv_list_count++; 1669 1670 splx(s); 1671} 1672 1673/* 1674 * pmap_remove_pte: do the things to unmap a page in a process 1675 */ 1676static int 1677pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1678{ 1679 pt_entry_t oldpte; 1680 vm_page_t m; 1681 1682 oldpte = atomic_readandclear_int(ptq); 1683 if (oldpte & PG_W) 1684 pmap->pm_stats.wired_count -= 1; 1685 /* 1686 * Machines that don't support invlpg, also don't support 1687 * PG_G. 1688 */ 1689 if (oldpte & PG_G) 1690 pmap_invalidate_page(kernel_pmap, va); 1691 pmap->pm_stats.resident_count -= 1; 1692 if (oldpte & PG_MANAGED) { 1693 m = PHYS_TO_VM_PAGE(oldpte); 1694 if (oldpte & PG_M) { 1695#if defined(PMAP_DIAGNOSTIC) 1696 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1697 printf( 1698 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1699 va, oldpte); 1700 } 1701#endif 1702 if (pmap_track_modified(va)) 1703 vm_page_dirty(m); 1704 } 1705 if (oldpte & PG_A) 1706 vm_page_flag_set(m, PG_REFERENCED); 1707 return pmap_remove_entry(pmap, m, va); 1708 } else { 1709 return pmap_unuse_pt(pmap, va, NULL); 1710 } 1711 1712 return 0; 1713} 1714 1715/* 1716 * Remove a single page from a process address space 1717 */ 1718static void 1719pmap_remove_page(pmap_t pmap, vm_offset_t va) 1720{ 1721 register pt_entry_t *ptq; 1722 1723 /* 1724 * if there is no pte for this address, just skip it!!! 1725 */ 1726 if (*pmap_pde(pmap, va) == 0) { 1727 return; 1728 } 1729 1730 /* 1731 * get a local va for mappings for this pmap. 1732 */ 1733 ptq = get_ptbase(pmap) + i386_btop(va); 1734 if (*ptq) { 1735 (void) pmap_remove_pte(pmap, ptq, va); 1736 pmap_invalidate_page(pmap, va); 1737 } 1738 return; 1739} 1740 1741/* 1742 * Remove the given range of addresses from the specified map. 1743 * 1744 * It is assumed that the start and end are properly 1745 * rounded to the page size. 1746 */ 1747void 1748pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1749{ 1750 register pt_entry_t *ptbase; 1751 vm_offset_t pdnxt; 1752 pd_entry_t ptpaddr; 1753 vm_offset_t sindex, eindex; 1754 int anyvalid; 1755 1756 if (pmap == NULL) 1757 return; 1758 1759 if (pmap->pm_stats.resident_count == 0) 1760 return; 1761 1762 /* 1763 * special handling of removing one page. a very 1764 * common operation and easy to short circuit some 1765 * code. 1766 */ 1767 if ((sva + PAGE_SIZE == eva) && 1768 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1769 pmap_remove_page(pmap, sva); 1770 return; 1771 } 1772 1773 anyvalid = 0; 1774 1775 /* 1776 * Get a local virtual address for the mappings that are being 1777 * worked with. 1778 */ 1779 ptbase = get_ptbase(pmap); 1780 1781 sindex = i386_btop(sva); 1782 eindex = i386_btop(eva); 1783 1784 for (; sindex < eindex; sindex = pdnxt) { 1785 unsigned pdirindex; 1786 1787 /* 1788 * Calculate index for next page table. 1789 */ 1790 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1791 if (pmap->pm_stats.resident_count == 0) 1792 break; 1793 1794 pdirindex = sindex / NPDEPG; 1795 ptpaddr = pmap->pm_pdir[pdirindex]; 1796 if ((ptpaddr & PG_PS) != 0) { 1797 pmap->pm_pdir[pdirindex] = 0; 1798 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1799 anyvalid++; 1800 continue; 1801 } 1802 1803 /* 1804 * Weed out invalid mappings. Note: we assume that the page 1805 * directory table is always allocated, and in kernel virtual. 1806 */ 1807 if (ptpaddr == 0) 1808 continue; 1809 1810 /* 1811 * Limit our scan to either the end of the va represented 1812 * by the current page table page, or to the end of the 1813 * range being removed. 1814 */ 1815 if (pdnxt > eindex) { 1816 pdnxt = eindex; 1817 } 1818 1819 for (; sindex != pdnxt; sindex++) { 1820 vm_offset_t va; 1821 if (ptbase[sindex] == 0) { 1822 continue; 1823 } 1824 va = i386_ptob(sindex); 1825 1826 anyvalid++; 1827 if (pmap_remove_pte(pmap, 1828 ptbase + sindex, va)) 1829 break; 1830 } 1831 } 1832 1833 if (anyvalid) 1834 pmap_invalidate_all(pmap); 1835} 1836 1837/* 1838 * Routine: pmap_remove_all 1839 * Function: 1840 * Removes this physical page from 1841 * all physical maps in which it resides. 1842 * Reflects back modify bits to the pager. 1843 * 1844 * Notes: 1845 * Original versions of this routine were very 1846 * inefficient because they iteratively called 1847 * pmap_remove (slow...) 1848 */ 1849 1850static void 1851pmap_remove_all(vm_page_t m) 1852{ 1853 register pv_entry_t pv; 1854 pt_entry_t *pte, tpte; 1855 int s; 1856 1857#if defined(PMAP_DIAGNOSTIC) 1858 /* 1859 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1860 * pages! 1861 */ 1862 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1863 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1864 } 1865#endif 1866 1867 s = splvm(); 1868 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1869 pv->pv_pmap->pm_stats.resident_count--; 1870 1871 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1872 1873 tpte = atomic_readandclear_int(pte); 1874 if (tpte & PG_W) 1875 pv->pv_pmap->pm_stats.wired_count--; 1876 1877 if (tpte & PG_A) 1878 vm_page_flag_set(m, PG_REFERENCED); 1879 1880 /* 1881 * Update the vm_page_t clean and reference bits. 1882 */ 1883 if (tpte & PG_M) { 1884#if defined(PMAP_DIAGNOSTIC) 1885 if (pmap_nw_modified((pt_entry_t) tpte)) { 1886 printf( 1887 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1888 pv->pv_va, tpte); 1889 } 1890#endif 1891 if (pmap_track_modified(pv->pv_va)) 1892 vm_page_dirty(m); 1893 } 1894 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1895 1896 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1897 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1898 m->md.pv_list_count--; 1899 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1900 free_pv_entry(pv); 1901 } 1902 1903 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1904 1905 splx(s); 1906} 1907 1908/* 1909 * Set the physical protection on the 1910 * specified range of this map as requested. 1911 */ 1912void 1913pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1914{ 1915 register pt_entry_t *ptbase; 1916 vm_offset_t pdnxt; 1917 pd_entry_t ptpaddr; 1918 vm_offset_t sindex, eindex; 1919 int anychanged; 1920 1921 if (pmap == NULL) 1922 return; 1923 1924 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1925 pmap_remove(pmap, sva, eva); 1926 return; 1927 } 1928 1929 if (prot & VM_PROT_WRITE) 1930 return; 1931 1932 anychanged = 0; 1933 1934 ptbase = get_ptbase(pmap); 1935 1936 sindex = i386_btop(sva); 1937 eindex = i386_btop(eva); 1938 1939 for (; sindex < eindex; sindex = pdnxt) { 1940 1941 unsigned pdirindex; 1942 1943 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1944 1945 pdirindex = sindex / NPDEPG; 1946 ptpaddr = pmap->pm_pdir[pdirindex]; 1947 if ((ptpaddr & PG_PS) != 0) { 1948 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1949 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1950 anychanged++; 1951 continue; 1952 } 1953 1954 /* 1955 * Weed out invalid mappings. Note: we assume that the page 1956 * directory table is always allocated, and in kernel virtual. 1957 */ 1958 if (ptpaddr == 0) 1959 continue; 1960 1961 if (pdnxt > eindex) { 1962 pdnxt = eindex; 1963 } 1964 1965 for (; sindex != pdnxt; sindex++) { 1966 1967 pt_entry_t pbits; 1968 vm_page_t m; 1969 1970 pbits = ptbase[sindex]; 1971 1972 if (pbits & PG_MANAGED) { 1973 m = NULL; 1974 if (pbits & PG_A) { 1975 m = PHYS_TO_VM_PAGE(pbits); 1976 vm_page_flag_set(m, PG_REFERENCED); 1977 pbits &= ~PG_A; 1978 } 1979 if (pbits & PG_M) { 1980 if (pmap_track_modified(i386_ptob(sindex))) { 1981 if (m == NULL) 1982 m = PHYS_TO_VM_PAGE(pbits); 1983 vm_page_dirty(m); 1984 pbits &= ~PG_M; 1985 } 1986 } 1987 } 1988 1989 pbits &= ~PG_RW; 1990 1991 if (pbits != ptbase[sindex]) { 1992 ptbase[sindex] = pbits; 1993 anychanged = 1; 1994 } 1995 } 1996 } 1997 if (anychanged) 1998 pmap_invalidate_all(pmap); 1999} 2000 2001/* 2002 * Insert the given physical page (p) at 2003 * the specified virtual address (v) in the 2004 * target physical map with the protection requested. 2005 * 2006 * If specified, the page will be wired down, meaning 2007 * that the related pte can not be reclaimed. 2008 * 2009 * NB: This is the only routine which MAY NOT lazy-evaluate 2010 * or lose information. That is, this routine must actually 2011 * insert this page into the given map NOW. 2012 */ 2013void 2014pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2015 boolean_t wired) 2016{ 2017 vm_offset_t pa; 2018 register pt_entry_t *pte; 2019 vm_offset_t opa; 2020 pt_entry_t origpte, newpte; 2021 vm_page_t mpte; 2022 2023 if (pmap == NULL) 2024 return; 2025 2026 va &= PG_FRAME; 2027#ifdef PMAP_DIAGNOSTIC 2028 if (va > VM_MAX_KERNEL_ADDRESS) 2029 panic("pmap_enter: toobig"); 2030 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2031 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2032#endif 2033 2034 mpte = NULL; 2035 /* 2036 * In the case that a page table page is not 2037 * resident, we are creating it here. 2038 */ 2039 if (va < VM_MAXUSER_ADDRESS) { 2040 mpte = pmap_allocpte(pmap, va); 2041 } 2042#if 0 && defined(PMAP_DIAGNOSTIC) 2043 else { 2044 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2045 origpte = *pdeaddr; 2046 if ((origpte & PG_V) == 0) { 2047 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2048 pmap->pm_pdir[PTDPTDI], origpte, va); 2049 } 2050 } 2051#endif 2052 2053 pte = pmap_pte(pmap, va); 2054 2055 /* 2056 * Page Directory table entry not valid, we need a new PT page 2057 */ 2058 if (pte == NULL) { 2059 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2060 (void *)pmap->pm_pdir[PTDPTDI], va); 2061 } 2062 2063 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2064 origpte = *(vm_offset_t *)pte; 2065 opa = origpte & PG_FRAME; 2066 2067 if (origpte & PG_PS) 2068 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2069 2070 /* 2071 * Mapping has not changed, must be protection or wiring change. 2072 */ 2073 if (origpte && (opa == pa)) { 2074 /* 2075 * Wiring change, just update stats. We don't worry about 2076 * wiring PT pages as they remain resident as long as there 2077 * are valid mappings in them. Hence, if a user page is wired, 2078 * the PT page will be also. 2079 */ 2080 if (wired && ((origpte & PG_W) == 0)) 2081 pmap->pm_stats.wired_count++; 2082 else if (!wired && (origpte & PG_W)) 2083 pmap->pm_stats.wired_count--; 2084 2085#if defined(PMAP_DIAGNOSTIC) 2086 if (pmap_nw_modified((pt_entry_t) origpte)) { 2087 printf( 2088 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2089 va, origpte); 2090 } 2091#endif 2092 2093 /* 2094 * Remove extra pte reference 2095 */ 2096 if (mpte) 2097 mpte->hold_count--; 2098 2099 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2100 if ((origpte & PG_RW) == 0) { 2101 *pte |= PG_RW; 2102 pmap_invalidate_page(pmap, va); 2103 } 2104 return; 2105 } 2106 2107 /* 2108 * We might be turning off write access to the page, 2109 * so we go ahead and sense modify status. 2110 */ 2111 if (origpte & PG_MANAGED) { 2112 if ((origpte & PG_M) && pmap_track_modified(va)) { 2113 vm_page_t om; 2114 om = PHYS_TO_VM_PAGE(opa); 2115 vm_page_dirty(om); 2116 } 2117 pa |= PG_MANAGED; 2118 } 2119 goto validate; 2120 } 2121 /* 2122 * Mapping has changed, invalidate old range and fall through to 2123 * handle validating new mapping. 2124 */ 2125 if (opa) { 2126 int err; 2127 err = pmap_remove_pte(pmap, pte, va); 2128 if (err) 2129 panic("pmap_enter: pte vanished, va: 0x%x", va); 2130 } 2131 2132 /* 2133 * Enter on the PV list if part of our managed memory. Note that we 2134 * raise IPL while manipulating pv_table since pmap_enter can be 2135 * called at interrupt time. 2136 */ 2137 if (pmap_initialized && 2138 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2139 pmap_insert_entry(pmap, va, mpte, m); 2140 pa |= PG_MANAGED; 2141 } 2142 2143 /* 2144 * Increment counters 2145 */ 2146 pmap->pm_stats.resident_count++; 2147 if (wired) 2148 pmap->pm_stats.wired_count++; 2149 2150validate: 2151 /* 2152 * Now validate mapping with desired protection/wiring. 2153 */ 2154 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2155 2156 if (wired) 2157 newpte |= PG_W; 2158 if (va < VM_MAXUSER_ADDRESS) 2159 newpte |= PG_U; 2160 if (pmap == kernel_pmap) 2161 newpte |= pgeflag; 2162 2163 /* 2164 * if the mapping or permission bits are different, we need 2165 * to update the pte. 2166 */ 2167 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2168 *pte = newpte | PG_A; 2169 /*if (origpte)*/ { 2170 pmap_invalidate_page(pmap, va); 2171 } 2172 } 2173} 2174 2175/* 2176 * this code makes some *MAJOR* assumptions: 2177 * 1. Current pmap & pmap exists. 2178 * 2. Not wired. 2179 * 3. Read access. 2180 * 4. No page table pages. 2181 * 5. Tlbflush is deferred to calling procedure. 2182 * 6. Page IS managed. 2183 * but is *MUCH* faster than pmap_enter... 2184 */ 2185 2186static vm_page_t 2187pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2188{ 2189 pt_entry_t *pte; 2190 vm_offset_t pa; 2191 2192 /* 2193 * In the case that a page table page is not 2194 * resident, we are creating it here. 2195 */ 2196 if (va < VM_MAXUSER_ADDRESS) { 2197 unsigned ptepindex; 2198 pd_entry_t ptepa; 2199 2200 /* 2201 * Calculate pagetable page index 2202 */ 2203 ptepindex = va >> PDRSHIFT; 2204 if (mpte && (mpte->pindex == ptepindex)) { 2205 mpte->hold_count++; 2206 } else { 2207retry: 2208 /* 2209 * Get the page directory entry 2210 */ 2211 ptepa = pmap->pm_pdir[ptepindex]; 2212 2213 /* 2214 * If the page table page is mapped, we just increment 2215 * the hold count, and activate it. 2216 */ 2217 if (ptepa) { 2218 if (ptepa & PG_PS) 2219 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2220 if (pmap->pm_ptphint && 2221 (pmap->pm_ptphint->pindex == ptepindex)) { 2222 mpte = pmap->pm_ptphint; 2223 } else { 2224 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2225 pmap->pm_ptphint = mpte; 2226 } 2227 if (mpte == NULL) 2228 goto retry; 2229 mpte->hold_count++; 2230 } else { 2231 mpte = _pmap_allocpte(pmap, ptepindex); 2232 } 2233 } 2234 } else { 2235 mpte = NULL; 2236 } 2237 2238 /* 2239 * This call to vtopte makes the assumption that we are 2240 * entering the page into the current pmap. In order to support 2241 * quick entry into any pmap, one would likely use pmap_pte_quick. 2242 * But that isn't as quick as vtopte. 2243 */ 2244 pte = vtopte(va); 2245 if (*pte) { 2246 if (mpte) 2247 pmap_unwire_pte_hold(pmap, mpte); 2248 return 0; 2249 } 2250 2251 /* 2252 * Enter on the PV list if part of our managed memory. Note that we 2253 * raise IPL while manipulating pv_table since pmap_enter can be 2254 * called at interrupt time. 2255 */ 2256 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2257 pmap_insert_entry(pmap, va, mpte, m); 2258 2259 /* 2260 * Increment counters 2261 */ 2262 pmap->pm_stats.resident_count++; 2263 2264 pa = VM_PAGE_TO_PHYS(m); 2265 2266 /* 2267 * Now validate mapping with RO protection 2268 */ 2269 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2270 *pte = pa | PG_V | PG_U; 2271 else 2272 *pte = pa | PG_V | PG_U | PG_MANAGED; 2273 2274 return mpte; 2275} 2276 2277/* 2278 * Make a temporary mapping for a physical address. This is only intended 2279 * to be used for panic dumps. 2280 */ 2281void * 2282pmap_kenter_temporary(vm_offset_t pa, int i) 2283{ 2284 vm_offset_t va; 2285 2286 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE); 2287 pmap_kenter(va, pa); 2288#ifndef I386_CPU 2289 invlpg(va); 2290#else 2291 invltlb(); 2292#endif 2293 return ((void *)crashdumpmap); 2294} 2295 2296#define MAX_INIT_PT (96) 2297/* 2298 * pmap_object_init_pt preloads the ptes for a given object 2299 * into the specified pmap. This eliminates the blast of soft 2300 * faults on process startup and immediately after an mmap. 2301 */ 2302void 2303pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2304 vm_object_t object, vm_pindex_t pindex, 2305 vm_size_t size, int limit) 2306{ 2307 vm_offset_t tmpidx; 2308 int psize; 2309 vm_page_t p, mpte; 2310 int objpgs; 2311 2312 if (pmap == NULL || object == NULL) 2313 return; 2314 2315 /* 2316 * This code maps large physical mmap regions into the 2317 * processor address space. Note that some shortcuts 2318 * are taken, but the code works. 2319 */ 2320 if (pseflag && (object->type == OBJT_DEVICE) && 2321 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2322 int i; 2323 vm_page_t m[1]; 2324 unsigned int ptepindex; 2325 int npdes; 2326 pd_entry_t ptepa; 2327 2328 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2329 return; 2330 2331retry: 2332 p = vm_page_lookup(object, pindex); 2333 if (p && vm_page_sleep_busy(p, FALSE, "init4p")) 2334 goto retry; 2335 2336 if (p == NULL) { 2337 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2338 if (p == NULL) 2339 return; 2340 m[0] = p; 2341 2342 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2343 vm_page_free(p); 2344 return; 2345 } 2346 2347 p = vm_page_lookup(object, pindex); 2348 vm_page_wakeup(p); 2349 } 2350 2351 ptepa = VM_PAGE_TO_PHYS(p); 2352 if (ptepa & (NBPDR - 1)) { 2353 return; 2354 } 2355 2356 p->valid = VM_PAGE_BITS_ALL; 2357 2358 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2359 npdes = size >> PDRSHIFT; 2360 for(i = 0; i < npdes; i++) { 2361 pmap->pm_pdir[ptepindex] = 2362 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2363 ptepa += NBPDR; 2364 ptepindex += 1; 2365 } 2366 vm_page_flag_set(p, PG_MAPPED); 2367 pmap_invalidate_all(kernel_pmap); 2368 return; 2369 } 2370 2371 psize = i386_btop(size); 2372 2373 if ((object->type != OBJT_VNODE) || 2374 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2375 (object->resident_page_count > MAX_INIT_PT))) { 2376 return; 2377 } 2378 2379 if (psize + pindex > object->size) { 2380 if (object->size < pindex) 2381 return; 2382 psize = object->size - pindex; 2383 } 2384 2385 mpte = NULL; 2386 /* 2387 * if we are processing a major portion of the object, then scan the 2388 * entire thing. 2389 */ 2390 if (psize > (object->resident_page_count >> 2)) { 2391 objpgs = psize; 2392 2393 for (p = TAILQ_FIRST(&object->memq); 2394 ((objpgs > 0) && (p != NULL)); 2395 p = TAILQ_NEXT(p, listq)) { 2396 2397 if (p->pindex < pindex || p->pindex - pindex >= psize) { 2398 continue; 2399 } 2400 tmpidx = p->pindex - pindex; 2401 /* 2402 * don't allow an madvise to blow away our really 2403 * free pages allocating pv entries. 2404 */ 2405 if ((limit & MAP_PREFAULT_MADVISE) && 2406 cnt.v_free_count < cnt.v_free_reserved) { 2407 break; 2408 } 2409 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2410 (p->busy == 0) && 2411 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2412 if ((p->queue - p->pc) == PQ_CACHE) 2413 vm_page_deactivate(p); 2414 vm_page_busy(p); 2415 mpte = pmap_enter_quick(pmap, 2416 addr + i386_ptob(tmpidx), p, mpte); 2417 vm_page_flag_set(p, PG_MAPPED); 2418 vm_page_wakeup(p); 2419 } 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 && 2437 ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2438 (p->busy == 0) && 2439 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2440 if ((p->queue - p->pc) == PQ_CACHE) 2441 vm_page_deactivate(p); 2442 vm_page_busy(p); 2443 mpte = pmap_enter_quick(pmap, 2444 addr + i386_ptob(tmpidx), p, mpte); 2445 vm_page_flag_set(p, PG_MAPPED); 2446 vm_page_wakeup(p); 2447 } 2448 } 2449 } 2450 return; 2451} 2452 2453/* 2454 * pmap_prefault provides a quick way of clustering 2455 * pagefaults into a processes address space. It is a "cousin" 2456 * of pmap_object_init_pt, except it runs at page fault time instead 2457 * of mmap time. 2458 */ 2459#define PFBAK 4 2460#define PFFOR 4 2461#define PAGEORDER_SIZE (PFBAK+PFFOR) 2462 2463static int pmap_prefault_pageorder[] = { 2464 -PAGE_SIZE, PAGE_SIZE, 2465 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2466 -3 * PAGE_SIZE, 3 * PAGE_SIZE 2467 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2468}; 2469 2470void 2471pmap_prefault(pmap, addra, entry) 2472 pmap_t pmap; 2473 vm_offset_t addra; 2474 vm_map_entry_t entry; 2475{ 2476 int i; 2477 vm_offset_t starta; 2478 vm_offset_t addr; 2479 vm_pindex_t pindex; 2480 vm_page_t m, mpte; 2481 vm_object_t object; 2482 2483 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2484 return; 2485 2486 object = entry->object.vm_object; 2487 2488 starta = addra - PFBAK * PAGE_SIZE; 2489 if (starta < entry->start) { 2490 starta = entry->start; 2491 } else if (starta > addra) { 2492 starta = 0; 2493 } 2494 2495 mpte = NULL; 2496 for (i = 0; i < PAGEORDER_SIZE; i++) { 2497 vm_object_t lobject; 2498 pt_entry_t *pte; 2499 2500 addr = addra + pmap_prefault_pageorder[i]; 2501 if (addr > addra + (PFFOR * PAGE_SIZE)) 2502 addr = 0; 2503 2504 if (addr < starta || addr >= entry->end) 2505 continue; 2506 2507 if ((*pmap_pde(pmap, addr)) == NULL) 2508 continue; 2509 2510 pte = vtopte(addr); 2511 if (*pte) 2512 continue; 2513 2514 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2515 lobject = object; 2516 for (m = vm_page_lookup(lobject, pindex); 2517 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2518 lobject = lobject->backing_object) { 2519 if (lobject->backing_object_offset & PAGE_MASK) 2520 break; 2521 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2522 m = vm_page_lookup(lobject->backing_object, pindex); 2523 } 2524 2525 /* 2526 * give-up when a page is not in memory 2527 */ 2528 if (m == NULL) 2529 break; 2530 2531 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2532 (m->busy == 0) && 2533 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2534 2535 if ((m->queue - m->pc) == PQ_CACHE) { 2536 vm_page_deactivate(m); 2537 } 2538 vm_page_busy(m); 2539 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2540 vm_page_flag_set(m, PG_MAPPED); 2541 vm_page_wakeup(m); 2542 } 2543 } 2544} 2545 2546/* 2547 * Routine: pmap_change_wiring 2548 * Function: Change the wiring attribute for a map/virtual-address 2549 * pair. 2550 * In/out conditions: 2551 * The mapping must already exist in the pmap. 2552 */ 2553void 2554pmap_change_wiring(pmap, va, wired) 2555 register pmap_t pmap; 2556 vm_offset_t va; 2557 boolean_t wired; 2558{ 2559 register pt_entry_t *pte; 2560 2561 if (pmap == NULL) 2562 return; 2563 2564 pte = pmap_pte(pmap, va); 2565 2566 if (wired && !pmap_pte_w(pte)) 2567 pmap->pm_stats.wired_count++; 2568 else if (!wired && pmap_pte_w(pte)) 2569 pmap->pm_stats.wired_count--; 2570 2571 /* 2572 * Wiring is not a hardware characteristic so there is no need to 2573 * invalidate TLB. 2574 */ 2575 pmap_pte_set_w(pte, wired); 2576} 2577 2578 2579 2580/* 2581 * Copy the range specified by src_addr/len 2582 * from the source map to the range dst_addr/len 2583 * in the destination map. 2584 * 2585 * This routine is only advisory and need not do anything. 2586 */ 2587 2588void 2589pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2590 vm_offset_t src_addr) 2591{ 2592 vm_offset_t addr; 2593 vm_offset_t end_addr = src_addr + len; 2594 vm_offset_t pdnxt; 2595 pd_entry_t src_frame, dst_frame; 2596 vm_page_t m; 2597 2598 if (dst_addr != src_addr) 2599 return; 2600 2601 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2602 if (src_frame != (PTDpde & PG_FRAME)) 2603 return; 2604 2605 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2606 for (addr = src_addr; addr < end_addr; addr = pdnxt) { 2607 pt_entry_t *src_pte, *dst_pte; 2608 vm_page_t dstmpte, srcmpte; 2609 pd_entry_t srcptepaddr; 2610 unsigned ptepindex; 2611 2612 if (addr >= UPT_MIN_ADDRESS) 2613 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2614 2615 /* 2616 * Don't let optional prefaulting of pages make us go 2617 * way below the low water mark of free pages or way 2618 * above high water mark of used pv entries. 2619 */ 2620 if (cnt.v_free_count < cnt.v_free_reserved || 2621 pv_entry_count > pv_entry_high_water) 2622 break; 2623 2624 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2625 ptepindex = addr >> PDRSHIFT; 2626 2627 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2628 if (srcptepaddr == 0) 2629 continue; 2630 2631 if (srcptepaddr & PG_PS) { 2632 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2633 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2634 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2635 } 2636 continue; 2637 } 2638 2639 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2640 if ((srcmpte == NULL) || 2641 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2642 continue; 2643 2644 if (pdnxt > end_addr) 2645 pdnxt = end_addr; 2646 2647 /* 2648 * Have to recheck this before every avtopte() call below 2649 * in case we have blocked and something else used APTDpde. 2650 */ 2651 if (dst_frame != (APTDpde & PG_FRAME)) { 2652 APTDpde = dst_frame | PG_RW | PG_V; 2653 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 2654 } 2655 src_pte = vtopte(addr); 2656 dst_pte = avtopte(addr); 2657 while (addr < pdnxt) { 2658 pt_entry_t ptetemp; 2659 ptetemp = *src_pte; 2660 /* 2661 * we only virtual copy managed pages 2662 */ 2663 if ((ptetemp & PG_MANAGED) != 0) { 2664 /* 2665 * We have to check after allocpte for the 2666 * pte still being around... allocpte can 2667 * block. 2668 */ 2669 dstmpte = pmap_allocpte(dst_pmap, addr); 2670 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2671 /* 2672 * Clear the modified and 2673 * accessed (referenced) bits 2674 * during the copy. 2675 */ 2676 m = PHYS_TO_VM_PAGE(ptetemp); 2677 *dst_pte = ptetemp & ~(PG_M | PG_A); 2678 dst_pmap->pm_stats.resident_count++; 2679 pmap_insert_entry(dst_pmap, addr, 2680 dstmpte, m); 2681 } else { 2682 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2683 } 2684 if (dstmpte->hold_count >= srcmpte->hold_count) 2685 break; 2686 } 2687 addr += PAGE_SIZE; 2688 src_pte++; 2689 dst_pte++; 2690 } 2691 } 2692} 2693 2694#ifdef SMP 2695 2696/* 2697 * pmap_zpi_switchin*() 2698 * 2699 * These functions allow us to avoid doing IPIs alltogether in certain 2700 * temporary page-mapping situations (page zeroing). Instead to deal 2701 * with being preempted and moved onto a different cpu we invalidate 2702 * the page when the scheduler switches us in. This does not occur 2703 * very often so we remain relatively optimal with very little effort. 2704 */ 2705static void 2706pmap_zpi_switchin12(void) 2707{ 2708 invlpg((u_int)CADDR1); 2709 invlpg((u_int)CADDR2); 2710} 2711 2712static void 2713pmap_zpi_switchin2(void) 2714{ 2715 invlpg((u_int)CADDR2); 2716} 2717 2718static void 2719pmap_zpi_switchin3(void) 2720{ 2721 invlpg((u_int)CADDR3); 2722} 2723 2724#endif 2725 2726/* 2727 * pmap_zero_page zeros the specified hardware page by mapping 2728 * the page into KVM and using bzero to clear its contents. 2729 */ 2730void 2731pmap_zero_page(vm_page_t m) 2732{ 2733 vm_offset_t phys; 2734 2735 phys = VM_PAGE_TO_PHYS(m); 2736 if (*CMAP2) 2737 panic("pmap_zero_page: CMAP2 busy"); 2738 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2739#ifdef I386_CPU 2740 invltlb(); 2741#else 2742#ifdef SMP 2743 curthread->td_switchin = pmap_zpi_switchin2; 2744#endif 2745 invlpg((u_int)CADDR2); 2746#endif 2747#if defined(I686_CPU) 2748 if (cpu_class == CPUCLASS_686) 2749 i686_pagezero(CADDR2); 2750 else 2751#endif 2752 bzero(CADDR2, PAGE_SIZE); 2753#ifdef SMP 2754 curthread->td_switchin = NULL; 2755#endif 2756 *CMAP2 = 0; 2757} 2758 2759/* 2760 * pmap_zero_page_area zeros the specified hardware page by mapping 2761 * the page into KVM and using bzero to clear its contents. 2762 * 2763 * off and size may not cover an area beyond a single hardware page. 2764 */ 2765void 2766pmap_zero_page_area(vm_page_t m, int off, int size) 2767{ 2768 vm_offset_t phys; 2769 2770 phys = VM_PAGE_TO_PHYS(m); 2771 if (*CMAP2) 2772 panic("pmap_zero_page: CMAP2 busy"); 2773 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2774#ifdef I386_CPU 2775 invltlb(); 2776#else 2777#ifdef SMP 2778 curthread->td_switchin = pmap_zpi_switchin2; 2779#endif 2780 invlpg((u_int)CADDR2); 2781#endif 2782#if defined(I686_CPU) 2783 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2784 i686_pagezero(CADDR2); 2785 else 2786#endif 2787 bzero((char *)CADDR2 + off, size); 2788#ifdef SMP 2789 curthread->td_switchin = NULL; 2790#endif 2791 *CMAP2 = 0; 2792} 2793 2794/* 2795 * pmap_zero_page_idle zeros the specified hardware page by mapping 2796 * the page into KVM and using bzero to clear its contents. This 2797 * is intended to be called from the vm_pagezero process only and 2798 * outside of Giant. 2799 */ 2800void 2801pmap_zero_page_idle(vm_page_t m) 2802{ 2803 vm_offset_t phys; 2804 2805 phys = VM_PAGE_TO_PHYS(m); 2806 if (*CMAP3) 2807 panic("pmap_zero_page: CMAP3 busy"); 2808 *CMAP3 = PG_V | PG_RW | phys | PG_A | PG_M; 2809#ifdef I386_CPU 2810 invltlb(); 2811#else 2812#ifdef SMP 2813 curthread->td_switchin = pmap_zpi_switchin3; 2814#endif 2815 invlpg((u_int)CADDR3); 2816#endif 2817#if defined(I686_CPU) 2818 if (cpu_class == CPUCLASS_686) 2819 i686_pagezero(CADDR3); 2820 else 2821#endif 2822 bzero(CADDR3, PAGE_SIZE); 2823#ifdef SMP 2824 curthread->td_switchin = NULL; 2825#endif 2826 *CMAP3 = 0; 2827} 2828 2829/* 2830 * pmap_copy_page copies the specified (machine independent) 2831 * page by mapping the page into virtual memory and using 2832 * bcopy to copy the page, one machine dependent page at a 2833 * time. 2834 */ 2835void 2836pmap_copy_page(vm_page_t src, vm_page_t dst) 2837{ 2838 2839 if (*CMAP1) 2840 panic("pmap_copy_page: CMAP1 busy"); 2841 if (*CMAP2) 2842 panic("pmap_copy_page: CMAP2 busy"); 2843 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2844 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2845#ifdef I386_CPU 2846 invltlb(); 2847#else 2848#ifdef SMP 2849 curthread->td_switchin = pmap_zpi_switchin12; 2850#endif 2851 invlpg((u_int)CADDR1); 2852 invlpg((u_int)CADDR2); 2853#endif 2854 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2855#ifdef SMP 2856 curthread->td_switchin = NULL; 2857#endif 2858 *CMAP1 = 0; 2859 *CMAP2 = 0; 2860} 2861 2862 2863/* 2864 * Routine: pmap_pageable 2865 * Function: 2866 * Make the specified pages (by pmap, offset) 2867 * pageable (or not) as requested. 2868 * 2869 * A page which is not pageable may not take 2870 * a fault; therefore, its page table entry 2871 * must remain valid for the duration. 2872 * 2873 * This routine is merely advisory; pmap_enter 2874 * will specify that these pages are to be wired 2875 * down (or not) as appropriate. 2876 */ 2877void 2878pmap_pageable(pmap, sva, eva, pageable) 2879 pmap_t pmap; 2880 vm_offset_t sva, eva; 2881 boolean_t pageable; 2882{ 2883} 2884 2885/* 2886 * Returns true if the pmap's pv is one of the first 2887 * 16 pvs linked to from this page. This count may 2888 * be changed upwards or downwards in the future; it 2889 * is only necessary that true be returned for a small 2890 * subset of pmaps for proper page aging. 2891 */ 2892boolean_t 2893pmap_page_exists_quick(pmap, m) 2894 pmap_t pmap; 2895 vm_page_t m; 2896{ 2897 pv_entry_t pv; 2898 int loops = 0; 2899 int s; 2900 2901 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2902 return FALSE; 2903 2904 s = splvm(); 2905 2906 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2907 if (pv->pv_pmap == pmap) { 2908 splx(s); 2909 return TRUE; 2910 } 2911 loops++; 2912 if (loops >= 16) 2913 break; 2914 } 2915 splx(s); 2916 return (FALSE); 2917} 2918 2919#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2920/* 2921 * Remove all pages from specified address space 2922 * this aids process exit speeds. Also, this code 2923 * is special cased for current process only, but 2924 * can have the more generic (and slightly slower) 2925 * mode enabled. This is much faster than pmap_remove 2926 * in the case of running down an entire address space. 2927 */ 2928void 2929pmap_remove_pages(pmap, sva, eva) 2930 pmap_t pmap; 2931 vm_offset_t sva, eva; 2932{ 2933 pt_entry_t *pte, tpte; 2934 vm_page_t m; 2935 pv_entry_t pv, npv; 2936 int s; 2937 2938#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2939 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2940 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2941 return; 2942 } 2943#endif 2944 2945 s = splvm(); 2946 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2947 2948 if (pv->pv_va >= eva || pv->pv_va < sva) { 2949 npv = TAILQ_NEXT(pv, pv_plist); 2950 continue; 2951 } 2952 2953#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2954 pte = vtopte(pv->pv_va); 2955#else 2956 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2957#endif 2958 tpte = *pte; 2959 2960 if (tpte == 0) { 2961 printf("TPTE at %p IS ZERO @ VA %08x\n", 2962 pte, pv->pv_va); 2963 panic("bad pte"); 2964 } 2965 2966/* 2967 * We cannot remove wired pages from a process' mapping at this time 2968 */ 2969 if (tpte & PG_W) { 2970 npv = TAILQ_NEXT(pv, pv_plist); 2971 continue; 2972 } 2973 2974 m = PHYS_TO_VM_PAGE(tpte); 2975 KASSERT(m->phys_addr == (tpte & PG_FRAME), 2976 ("vm_page_t %p phys_addr mismatch %08x %08x", 2977 m, m->phys_addr, tpte)); 2978 2979 KASSERT(m < &vm_page_array[vm_page_array_size], 2980 ("pmap_remove_pages: bad tpte %x", tpte)); 2981 2982 pv->pv_pmap->pm_stats.resident_count--; 2983 2984 *pte = 0; 2985 2986 /* 2987 * Update the vm_page_t clean and reference bits. 2988 */ 2989 if (tpte & PG_M) { 2990 vm_page_dirty(m); 2991 } 2992 2993 npv = TAILQ_NEXT(pv, pv_plist); 2994 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 2995 2996 m->md.pv_list_count--; 2997 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 2998 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 2999 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 3000 } 3001 3002 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 3003 free_pv_entry(pv); 3004 } 3005 splx(s); 3006 pmap_invalidate_all(pmap); 3007} 3008 3009/* 3010 * pmap_testbit tests bits in pte's 3011 * note that the testbit/changebit routines are inline, 3012 * and a lot of things compile-time evaluate. 3013 */ 3014static boolean_t 3015pmap_testbit(m, bit) 3016 vm_page_t m; 3017 int bit; 3018{ 3019 pv_entry_t pv; 3020 pt_entry_t *pte; 3021 int s; 3022 3023 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3024 return FALSE; 3025 3026 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 3027 return FALSE; 3028 3029 s = splvm(); 3030 3031 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3032 /* 3033 * if the bit being tested is the modified bit, then 3034 * mark clean_map and ptes as never 3035 * modified. 3036 */ 3037 if (bit & (PG_A|PG_M)) { 3038 if (!pmap_track_modified(pv->pv_va)) 3039 continue; 3040 } 3041 3042#if defined(PMAP_DIAGNOSTIC) 3043 if (!pv->pv_pmap) { 3044 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3045 continue; 3046 } 3047#endif 3048 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3049 if (*pte & bit) { 3050 splx(s); 3051 return TRUE; 3052 } 3053 } 3054 splx(s); 3055 return (FALSE); 3056} 3057 3058/* 3059 * this routine is used to modify bits in ptes 3060 */ 3061static __inline void 3062pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3063{ 3064 register pv_entry_t pv; 3065 register pt_entry_t *pte; 3066 int s; 3067 3068 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3069 return; 3070 3071 s = splvm(); 3072 3073 /* 3074 * Loop over all current mappings setting/clearing as appropos If 3075 * setting RO do we need to clear the VAC? 3076 */ 3077 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3078 /* 3079 * don't write protect pager mappings 3080 */ 3081 if (!setem && (bit == PG_RW)) { 3082 if (!pmap_track_modified(pv->pv_va)) 3083 continue; 3084 } 3085 3086#if defined(PMAP_DIAGNOSTIC) 3087 if (!pv->pv_pmap) { 3088 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3089 continue; 3090 } 3091#endif 3092 3093 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3094 3095 if (setem) { 3096 *pte |= bit; 3097 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3098 } else { 3099 pt_entry_t pbits = *pte; 3100 if (pbits & bit) { 3101 if (bit == PG_RW) { 3102 if (pbits & PG_M) { 3103 vm_page_dirty(m); 3104 } 3105 *pte = pbits & ~(PG_M|PG_RW); 3106 } else { 3107 *pte = pbits & ~bit; 3108 } 3109 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3110 } 3111 } 3112 } 3113 splx(s); 3114} 3115 3116/* 3117 * pmap_page_protect: 3118 * 3119 * Lower the permission for all mappings to a given page. 3120 */ 3121void 3122pmap_page_protect(vm_page_t m, vm_prot_t prot) 3123{ 3124 if ((prot & VM_PROT_WRITE) == 0) { 3125 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3126 pmap_changebit(m, PG_RW, FALSE); 3127 } else { 3128 pmap_remove_all(m); 3129 } 3130 } 3131} 3132 3133vm_offset_t 3134pmap_phys_address(ppn) 3135 int ppn; 3136{ 3137 return (i386_ptob(ppn)); 3138} 3139 3140/* 3141 * pmap_ts_referenced: 3142 * 3143 * Return a count of reference bits for a page, clearing those bits. 3144 * It is not necessary for every reference bit to be cleared, but it 3145 * is necessary that 0 only be returned when there are truly no 3146 * reference bits set. 3147 * 3148 * XXX: The exact number of bits to check and clear is a matter that 3149 * should be tested and standardized at some point in the future for 3150 * optimal aging of shared pages. 3151 */ 3152int 3153pmap_ts_referenced(vm_page_t m) 3154{ 3155 register pv_entry_t pv, pvf, pvn; 3156 pt_entry_t *pte; 3157 int s; 3158 int rtval = 0; 3159 3160 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3161 return (rtval); 3162 3163 s = splvm(); 3164 3165 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3166 3167 pvf = pv; 3168 3169 do { 3170 pvn = TAILQ_NEXT(pv, pv_list); 3171 3172 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3173 3174 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3175 3176 if (!pmap_track_modified(pv->pv_va)) 3177 continue; 3178 3179 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3180 3181 if (pte && (*pte & PG_A)) { 3182 *pte &= ~PG_A; 3183 3184 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3185 3186 rtval++; 3187 if (rtval > 4) { 3188 break; 3189 } 3190 } 3191 } while ((pv = pvn) != NULL && pv != pvf); 3192 } 3193 splx(s); 3194 3195 return (rtval); 3196} 3197 3198/* 3199 * pmap_is_modified: 3200 * 3201 * Return whether or not the specified physical page was modified 3202 * in any physical maps. 3203 */ 3204boolean_t 3205pmap_is_modified(vm_page_t m) 3206{ 3207 return pmap_testbit(m, PG_M); 3208} 3209 3210/* 3211 * Clear the modify bits on the specified physical page. 3212 */ 3213void 3214pmap_clear_modify(vm_page_t m) 3215{ 3216 pmap_changebit(m, PG_M, FALSE); 3217} 3218 3219/* 3220 * pmap_clear_reference: 3221 * 3222 * Clear the reference bit on the specified physical page. 3223 */ 3224void 3225pmap_clear_reference(vm_page_t m) 3226{ 3227 pmap_changebit(m, PG_A, FALSE); 3228} 3229 3230/* 3231 * Miscellaneous support routines follow 3232 */ 3233 3234static void 3235i386_protection_init() 3236{ 3237 register int *kp, prot; 3238 3239 kp = protection_codes; 3240 for (prot = 0; prot < 8; prot++) { 3241 switch (prot) { 3242 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3243 /* 3244 * Read access is also 0. There isn't any execute bit, 3245 * so just make it readable. 3246 */ 3247 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3248 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3249 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3250 *kp++ = 0; 3251 break; 3252 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3253 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3254 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3255 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3256 *kp++ = PG_RW; 3257 break; 3258 } 3259 } 3260} 3261 3262/* 3263 * Map a set of physical memory pages into the kernel virtual 3264 * address space. Return a pointer to where it is mapped. This 3265 * routine is intended to be used for mapping device memory, 3266 * NOT real memory. 3267 */ 3268void * 3269pmap_mapdev(pa, size) 3270 vm_offset_t pa; 3271 vm_size_t size; 3272{ 3273 vm_offset_t va, tmpva, offset; 3274 pt_entry_t *pte; 3275 3276 offset = pa & PAGE_MASK; 3277 size = roundup(offset + size, PAGE_SIZE); 3278 3279 GIANT_REQUIRED; 3280 3281 va = kmem_alloc_pageable(kernel_map, size); 3282 if (!va) 3283 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3284 3285 pa = pa & PG_FRAME; 3286 for (tmpva = va; size > 0; ) { 3287 pte = vtopte(tmpva); 3288 *pte = pa | PG_RW | PG_V | pgeflag; 3289 size -= PAGE_SIZE; 3290 tmpva += PAGE_SIZE; 3291 pa += PAGE_SIZE; 3292 } 3293 pmap_invalidate_range(kernel_pmap, va, tmpva); 3294 return ((void *)(va + offset)); 3295} 3296 3297void 3298pmap_unmapdev(va, size) 3299 vm_offset_t va; 3300 vm_size_t size; 3301{ 3302 vm_offset_t base, offset, tmpva; 3303 pt_entry_t *pte; 3304 3305 base = va & PG_FRAME; 3306 offset = va & PAGE_MASK; 3307 size = roundup(offset + size, PAGE_SIZE); 3308 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE) { 3309 pte = vtopte(tmpva); 3310 *pte = 0; 3311 } 3312 pmap_invalidate_range(kernel_pmap, va, tmpva); 3313 kmem_free(kernel_map, base, size); 3314} 3315 3316/* 3317 * perform the pmap work for mincore 3318 */ 3319int 3320pmap_mincore(pmap, addr) 3321 pmap_t pmap; 3322 vm_offset_t addr; 3323{ 3324 pt_entry_t *ptep, pte; 3325 vm_page_t m; 3326 int val = 0; 3327 3328 ptep = pmap_pte(pmap, addr); 3329 if (ptep == 0) { 3330 return 0; 3331 } 3332 3333 if ((pte = *ptep) != 0) { 3334 vm_offset_t pa; 3335 3336 val = MINCORE_INCORE; 3337 if ((pte & PG_MANAGED) == 0) 3338 return val; 3339 3340 pa = pte & PG_FRAME; 3341 3342 m = PHYS_TO_VM_PAGE(pa); 3343 3344 /* 3345 * Modified by us 3346 */ 3347 if (pte & PG_M) 3348 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3349 /* 3350 * Modified by someone 3351 */ 3352 else if (m->dirty || pmap_is_modified(m)) 3353 val |= MINCORE_MODIFIED_OTHER; 3354 /* 3355 * Referenced by us 3356 */ 3357 if (pte & PG_A) 3358 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3359 3360 /* 3361 * Referenced by someone 3362 */ 3363 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3364 val |= MINCORE_REFERENCED_OTHER; 3365 vm_page_flag_set(m, PG_REFERENCED); 3366 } 3367 } 3368 return val; 3369} 3370 3371void 3372pmap_activate(struct thread *td) 3373{ 3374 struct proc *p = td->td_proc; 3375 pmap_t pmap; 3376 u_int32_t cr3; 3377 3378 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3379#if defined(SMP) 3380 pmap->pm_active |= PCPU_GET(cpumask); 3381#else 3382 pmap->pm_active |= 1; 3383#endif 3384#if defined(SWTCH_OPTIM_STATS) 3385 tlb_flush_count++; 3386#endif 3387 cr3 = vtophys(pmap->pm_pdir); 3388 /* XXXKSE this is wrong. 3389 * pmap_activate is for the current thread on the current cpu 3390 */ 3391 if (p->p_flag & P_KSES) { 3392 /* Make sure all other cr3 entries are updated. */ 3393 /* what if they are running? XXXKSE (maybe abort them) */ 3394 FOREACH_THREAD_IN_PROC(p, td) { 3395 td->td_pcb->pcb_cr3 = cr3; 3396 } 3397 } else { 3398 td->td_pcb->pcb_cr3 = cr3; 3399 } 3400 load_cr3(cr3); 3401} 3402 3403vm_offset_t 3404pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3405{ 3406 3407 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3408 return addr; 3409 } 3410 3411 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3412 return addr; 3413} 3414 3415 3416#if defined(PMAP_DEBUG) 3417pmap_pid_dump(int pid) 3418{ 3419 pmap_t pmap; 3420 struct proc *p; 3421 int npte = 0; 3422 int index; 3423 3424 sx_slock(&allproc_lock); 3425 LIST_FOREACH(p, &allproc, p_list) { 3426 if (p->p_pid != pid) 3427 continue; 3428 3429 if (p->p_vmspace) { 3430 int i,j; 3431 index = 0; 3432 pmap = vmspace_pmap(p->p_vmspace); 3433 for (i = 0; i < NPDEPG; i++) { 3434 pd_entry_t *pde; 3435 pt_entry_t *pte; 3436 vm_offset_t base = i << PDRSHIFT; 3437 3438 pde = &pmap->pm_pdir[i]; 3439 if (pde && pmap_pde_v(pde)) { 3440 for (j = 0; j < NPTEPG; j++) { 3441 vm_offset_t va = base + (j << PAGE_SHIFT); 3442 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3443 if (index) { 3444 index = 0; 3445 printf("\n"); 3446 } 3447 sx_sunlock(&allproc_lock); 3448 return npte; 3449 } 3450 pte = pmap_pte_quick(pmap, va); 3451 if (pte && pmap_pte_v(pte)) { 3452 pt_entry_t pa; 3453 vm_page_t m; 3454 pa = *pte; 3455 m = PHYS_TO_VM_PAGE(pa); 3456 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3457 va, pa, m->hold_count, m->wire_count, m->flags); 3458 npte++; 3459 index++; 3460 if (index >= 2) { 3461 index = 0; 3462 printf("\n"); 3463 } else { 3464 printf(" "); 3465 } 3466 } 3467 } 3468 } 3469 } 3470 } 3471 } 3472 sx_sunlock(&allproc_lock); 3473 return npte; 3474} 3475#endif 3476 3477#if defined(DEBUG) 3478 3479static void pads(pmap_t pm); 3480void pmap_pvdump(vm_offset_t pa); 3481 3482/* print address space of pmap*/ 3483static void 3484pads(pm) 3485 pmap_t pm; 3486{ 3487 int i, j; 3488 vm_offset_t va; 3489 pt_entry_t *ptep; 3490 3491 if (pm == kernel_pmap) 3492 return; 3493 for (i = 0; i < NPDEPG; i++) 3494 if (pm->pm_pdir[i]) 3495 for (j = 0; j < NPTEPG; j++) { 3496 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3497 if (pm == kernel_pmap && va < KERNBASE) 3498 continue; 3499 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3500 continue; 3501 ptep = pmap_pte_quick(pm, va); 3502 if (pmap_pte_v(ptep)) 3503 printf("%x:%x ", va, *ptep); 3504 }; 3505 3506} 3507 3508void 3509pmap_pvdump(pa) 3510 vm_offset_t pa; 3511{ 3512 pv_entry_t pv; 3513 vm_page_t m; 3514 3515 printf("pa %x", pa); 3516 m = PHYS_TO_VM_PAGE(pa); 3517 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3518 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3519 pads(pv->pv_pmap); 3520 } 3521 printf(" "); 3522} 3523#endif 3524