pmap.c revision 110532
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 110532 2003-02-08 05:41:41Z 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); 154static struct pmaplist allpmaps; 155static struct mtx allpmaps_lock; 156 157vm_offset_t avail_start; /* PA of first available physical page */ 158vm_offset_t avail_end; /* PA of last available physical page */ 159vm_offset_t virtual_avail; /* VA of first avail page (after kernel bss) */ 160vm_offset_t virtual_end; /* VA of last avail page (end of kernel AS) */ 161static boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */ 162static int pgeflag; /* PG_G or-in */ 163static int pseflag; /* PG_PS or-in */ 164 165static vm_object_t kptobj; 166 167static int nkpt; 168vm_offset_t kernel_vm_end; 169extern u_int32_t KERNend; 170 171/* 172 * Data for the pv entry allocation mechanism 173 */ 174static uma_zone_t pvzone; 175static struct vm_object pvzone_obj; 176static int pv_entry_count = 0, pv_entry_max = 0, pv_entry_high_water = 0; 177int pmap_pagedaemon_waken; 178 179/* 180 * All those kernel PT submaps that BSD is so fond of 181 */ 182pt_entry_t *CMAP1 = 0; 183static pt_entry_t *CMAP2, *CMAP3, *ptmmap; 184caddr_t CADDR1 = 0, ptvmmap = 0; 185static caddr_t CADDR2, CADDR3; 186static pt_entry_t *msgbufmap; 187struct msgbuf *msgbufp = 0; 188 189/* 190 * Crashdump maps. 191 */ 192static pt_entry_t *pt_crashdumpmap; 193static caddr_t crashdumpmap; 194 195#ifdef SMP 196extern pt_entry_t *SMPpt; 197#endif 198static pt_entry_t *PMAP1 = 0; 199static pt_entry_t *PADDR1 = 0; 200 201static PMAP_INLINE void free_pv_entry(pv_entry_t pv); 202static pt_entry_t *get_ptbase(pmap_t pmap); 203static pv_entry_t get_pv_entry(void); 204static void i386_protection_init(void); 205static __inline void pmap_changebit(vm_page_t m, int bit, boolean_t setem); 206 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 void pmap_insert_entry(pmap_t pmap, vm_offset_t va, 214 vm_page_t mpte, vm_page_t m); 215 216static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va); 217 218static int pmap_release_free_page(pmap_t pmap, vm_page_t p); 219static vm_page_t _pmap_allocpte(pmap_t pmap, unsigned ptepindex); 220static pt_entry_t *pmap_pte_quick(pmap_t pmap, vm_offset_t va); 221static vm_page_t pmap_page_lookup(vm_object_t object, vm_pindex_t pindex); 222static int pmap_unuse_pt(pmap_t, vm_offset_t, vm_page_t); 223static vm_offset_t pmap_kmem_choose(vm_offset_t addr); 224static void *pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait); 225 226static pd_entry_t pdir4mb; 227 228/* 229 * Routine: pmap_pte 230 * Function: 231 * Extract the page table entry associated 232 * with the given map/virtual_address pair. 233 */ 234 235PMAP_INLINE pt_entry_t * 236pmap_pte(pmap, va) 237 register pmap_t pmap; 238 vm_offset_t va; 239{ 240 pd_entry_t *pdeaddr; 241 242 if (pmap) { 243 pdeaddr = pmap_pde(pmap, va); 244 if (*pdeaddr & PG_PS) 245 return pdeaddr; 246 if (*pdeaddr) { 247 return get_ptbase(pmap) + i386_btop(va); 248 } 249 } 250 return (0); 251} 252 253/* 254 * Move the kernel virtual free pointer to the next 255 * 4MB. This is used to help improve performance 256 * by using a large (4MB) page for much of the kernel 257 * (.text, .data, .bss) 258 */ 259static vm_offset_t 260pmap_kmem_choose(vm_offset_t addr) 261{ 262 vm_offset_t newaddr = addr; 263 264#ifndef DISABLE_PSE 265 if (cpu_feature & CPUID_PSE) 266 newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 267#endif 268 return newaddr; 269} 270 271/* 272 * Bootstrap the system enough to run with virtual memory. 273 * 274 * On the i386 this is called after mapping has already been enabled 275 * and just syncs the pmap module with what has already been done. 276 * [We can't call it easily with mapping off since the kernel is not 277 * mapped with PA == VA, hence we would have to relocate every address 278 * from the linked base (virtual) address "KERNBASE" to the actual 279 * (physical) address starting relative to 0] 280 */ 281void 282pmap_bootstrap(firstaddr, loadaddr) 283 vm_offset_t firstaddr; 284 vm_offset_t loadaddr; 285{ 286 vm_offset_t va; 287 pt_entry_t *pte; 288 int i; 289 290 avail_start = firstaddr; 291 292 /* 293 * XXX The calculation of virtual_avail is wrong. It's NKPT*PAGE_SIZE too 294 * large. It should instead be correctly calculated in locore.s and 295 * not based on 'first' (which is a physical address, not a virtual 296 * address, for the start of unused physical memory). The kernel 297 * page tables are NOT double mapped and thus should not be included 298 * in this calculation. 299 */ 300 virtual_avail = (vm_offset_t) KERNBASE + firstaddr; 301 virtual_avail = pmap_kmem_choose(virtual_avail); 302 303 virtual_end = VM_MAX_KERNEL_ADDRESS; 304 305 /* 306 * Initialize protection array. 307 */ 308 i386_protection_init(); 309 310 /* 311 * Initialize the kernel pmap (which is statically allocated). 312 */ 313 kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD); 314 kernel_pmap->pm_active = -1; /* don't allow deactivation */ 315 TAILQ_INIT(&kernel_pmap->pm_pvlist); 316 LIST_INIT(&allpmaps); 317 mtx_init(&allpmaps_lock, "allpmaps", NULL, MTX_SPIN); 318 mtx_lock_spin(&allpmaps_lock); 319 LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list); 320 mtx_unlock_spin(&allpmaps_lock); 321 nkpt = NKPT; 322 323 /* 324 * Reserve some special page table entries/VA space for temporary 325 * mapping of pages. 326 */ 327#define SYSMAP(c, p, v, n) \ 328 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n); 329 330 va = virtual_avail; 331 pte = (pt_entry_t *) pmap_pte(kernel_pmap, va); 332 333 /* 334 * CMAP1/CMAP2 are used for zeroing and copying pages. 335 * CMAP3 is used for the idle process page zeroing. 336 */ 337 SYSMAP(caddr_t, CMAP1, CADDR1, 1) 338 SYSMAP(caddr_t, CMAP2, CADDR2, 1) 339 SYSMAP(caddr_t, CMAP3, CADDR3, 1) 340 341 /* 342 * Crashdump maps. 343 */ 344 SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS); 345 346 /* 347 * ptvmmap is used for reading arbitrary physical pages via /dev/mem. 348 * XXX ptmmap is not used. 349 */ 350 SYSMAP(caddr_t, ptmmap, ptvmmap, 1) 351 352 /* 353 * msgbufp is used to map the system message buffer. 354 * XXX msgbufmap is not used. 355 */ 356 SYSMAP(struct msgbuf *, msgbufmap, msgbufp, 357 atop(round_page(MSGBUF_SIZE))) 358 359 /* 360 * ptemap is used for pmap_pte_quick 361 */ 362 SYSMAP(pt_entry_t *, PMAP1, PADDR1, 1); 363 364 virtual_avail = va; 365 366 *CMAP1 = *CMAP2 = 0; 367 for (i = 0; i < NKPT; i++) 368 PTD[i] = 0; 369 370 pgeflag = 0; 371#ifndef DISABLE_PG_G 372 if (cpu_feature & CPUID_PGE) 373 pgeflag = PG_G; 374#endif 375 376/* 377 * Initialize the 4MB page size flag 378 */ 379 pseflag = 0; 380/* 381 * The 4MB page version of the initial 382 * kernel page mapping. 383 */ 384 pdir4mb = 0; 385 386#ifndef DISABLE_PSE 387 if (cpu_feature & CPUID_PSE) { 388 pd_entry_t ptditmp; 389 /* 390 * Note that we have enabled PSE mode 391 */ 392 pseflag = PG_PS; 393 ptditmp = *(PTmap + i386_btop(KERNBASE)); 394 ptditmp &= ~(NBPDR - 1); 395 ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag; 396 pdir4mb = ptditmp; 397 } 398#endif 399#ifndef SMP 400 /* 401 * Turn on PGE/PSE. SMP does this later on since the 402 * 4K page tables are required for AP boot (for now). 403 * XXX fixme. 404 */ 405 pmap_set_opt(); 406#endif 407#ifdef SMP 408 if (cpu_apic_address == 0) 409 panic("pmap_bootstrap: no local apic! (non-SMP hardware?)"); 410 411 /* local apic is mapped on last page */ 412 SMPpt[NPTEPG - 1] = (pt_entry_t)(PG_V | PG_RW | PG_N | pgeflag | 413 (cpu_apic_address & PG_FRAME)); 414#endif 415 invltlb(); 416} 417 418/* 419 * Enable 4MB page mode for MP startup. Turn on PG_G support. 420 * BSP will run this after all the AP's have started up. 421 */ 422void 423pmap_set_opt(void) 424{ 425 pt_entry_t *pte; 426 vm_offset_t va, endva; 427 428 if (pgeflag && (cpu_feature & CPUID_PGE)) { 429 load_cr4(rcr4() | CR4_PGE); 430 invltlb(); /* Insurance */ 431 } 432#ifndef DISABLE_PSE 433 if (pseflag && (cpu_feature & CPUID_PSE)) { 434 load_cr4(rcr4() | CR4_PSE); 435 invltlb(); /* Insurance */ 436 } 437#endif 438 if (PCPU_GET(cpuid) == 0) { 439#ifndef DISABLE_PSE 440 if (pdir4mb) { 441 kernel_pmap->pm_pdir[KPTDI] = PTD[KPTDI] = pdir4mb; 442 invltlb(); /* Insurance */ 443 } 444#endif 445 if (pgeflag) { 446 /* Turn on PG_G for text, data, bss pages. */ 447 va = (vm_offset_t)btext; 448#ifndef DISABLE_PSE 449 if (pseflag && (cpu_feature & CPUID_PSE)) { 450 if (va < KERNBASE + (1 << PDRSHIFT)) 451 va = KERNBASE + (1 << PDRSHIFT); 452 } 453#endif 454 endva = KERNBASE + KERNend; 455 while (va < endva) { 456 pte = vtopte(va); 457 if (*pte) 458 *pte |= pgeflag; 459 va += PAGE_SIZE; 460 } 461 invltlb(); /* Insurance */ 462 } 463 /* 464 * We do not need to broadcast the invltlb here, because 465 * each AP does it the moment it is released from the boot 466 * lock. See ap_init(). 467 */ 468 } 469} 470 471static void * 472pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait) 473{ 474 *flags = UMA_SLAB_PRIV; 475 return (void *)kmem_alloc(kernel_map, bytes); 476} 477 478/* 479 * Initialize the pmap module. 480 * Called by vm_init, to initialize any structures that the pmap 481 * system needs to map virtual memory. 482 * pmap_init has been enhanced to support in a fairly consistant 483 * way, discontiguous physical memory. 484 */ 485void 486pmap_init(phys_start, phys_end) 487 vm_offset_t phys_start, phys_end; 488{ 489 int i; 490 int initial_pvs; 491 492 /* 493 * object for kernel page table pages 494 */ 495 kptobj = vm_object_allocate(OBJT_DEFAULT, NKPDE); 496 497 /* 498 * Allocate memory for random pmap data structures. Includes the 499 * pv_head_table. 500 */ 501 502 for(i = 0; i < vm_page_array_size; i++) { 503 vm_page_t m; 504 505 m = &vm_page_array[i]; 506 TAILQ_INIT(&m->md.pv_list); 507 m->md.pv_list_count = 0; 508 } 509 510 /* 511 * init the pv free list 512 */ 513 initial_pvs = vm_page_array_size; 514 if (initial_pvs < MINPV) 515 initial_pvs = MINPV; 516 pvzone = uma_zcreate("PV ENTRY", sizeof (struct pv_entry), NULL, NULL, 517 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM); 518 uma_zone_set_allocf(pvzone, pmap_allocf); 519 uma_prealloc(pvzone, initial_pvs); 520 521 /* 522 * Now it is safe to enable pv_table recording. 523 */ 524 pmap_initialized = TRUE; 525} 526 527/* 528 * Initialize the address space (zone) for the pv_entries. Set a 529 * high water mark so that the system can recover from excessive 530 * numbers of pv entries. 531 */ 532void 533pmap_init2() 534{ 535 int shpgperproc = PMAP_SHPGPERPROC; 536 537 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc); 538 pv_entry_max = shpgperproc * maxproc + vm_page_array_size; 539 TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max); 540 pv_entry_high_water = 9 * (pv_entry_max / 10); 541 uma_zone_set_obj(pvzone, &pvzone_obj, pv_entry_max); 542} 543 544 545/*************************************************** 546 * Low level helper routines..... 547 ***************************************************/ 548 549#if defined(PMAP_DIAGNOSTIC) 550 551/* 552 * This code checks for non-writeable/modified pages. 553 * This should be an invalid condition. 554 */ 555static int 556pmap_nw_modified(pt_entry_t ptea) 557{ 558 int pte; 559 560 pte = (int) ptea; 561 562 if ((pte & (PG_M|PG_RW)) == PG_M) 563 return 1; 564 else 565 return 0; 566} 567#endif 568 569 570/* 571 * this routine defines the region(s) of memory that should 572 * not be tested for the modified bit. 573 */ 574static PMAP_INLINE int 575pmap_track_modified(vm_offset_t va) 576{ 577 if ((va < kmi.clean_sva) || (va >= kmi.clean_eva)) 578 return 1; 579 else 580 return 0; 581} 582 583#ifdef I386_CPU 584/* 585 * i386 only has "invalidate everything" and no SMP to worry about. 586 */ 587PMAP_INLINE void 588pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 589{ 590 591 if (pmap == kernel_pmap || pmap->pm_active) 592 invltlb(); 593} 594 595PMAP_INLINE void 596pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 597{ 598 599 if (pmap == kernel_pmap || pmap->pm_active) 600 invltlb(); 601} 602 603PMAP_INLINE void 604pmap_invalidate_all(pmap_t pmap) 605{ 606 607 if (pmap == kernel_pmap || pmap->pm_active) 608 invltlb(); 609} 610#else /* !I386_CPU */ 611#ifdef SMP 612/* 613 * For SMP, these functions have to use the IPI mechanism for coherence. 614 */ 615void 616pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 617{ 618 u_int cpumask; 619 u_int other_cpus; 620 621 critical_enter(); 622 /* 623 * We need to disable interrupt preemption but MUST NOT have 624 * interrupts disabled here. 625 * XXX we may need to hold schedlock to get a coherent pm_active 626 */ 627 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 628 invlpg(va); 629 smp_invlpg(va); 630 } else { 631 cpumask = PCPU_GET(cpumask); 632 other_cpus = PCPU_GET(other_cpus); 633 if (pmap->pm_active & cpumask) 634 invlpg(va); 635 if (pmap->pm_active & other_cpus) 636 smp_masked_invlpg(pmap->pm_active & other_cpus, va); 637 } 638 critical_exit(); 639} 640 641void 642pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 643{ 644 u_int cpumask; 645 u_int other_cpus; 646 vm_offset_t addr; 647 648 critical_enter(); 649 /* 650 * We need to disable interrupt preemption but MUST NOT have 651 * interrupts disabled here. 652 * XXX we may need to hold schedlock to get a coherent pm_active 653 */ 654 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 655 for (addr = sva; addr < eva; addr += PAGE_SIZE) 656 invlpg(addr); 657 smp_invlpg_range(sva, eva); 658 } else { 659 cpumask = PCPU_GET(cpumask); 660 other_cpus = PCPU_GET(other_cpus); 661 if (pmap->pm_active & cpumask) 662 for (addr = sva; addr < eva; addr += PAGE_SIZE) 663 invlpg(addr); 664 if (pmap->pm_active & other_cpus) 665 smp_masked_invlpg_range(pmap->pm_active & other_cpus, 666 sva, eva); 667 } 668 critical_exit(); 669} 670 671void 672pmap_invalidate_all(pmap_t pmap) 673{ 674 u_int cpumask; 675 u_int other_cpus; 676 677#ifdef SWTCH_OPTIM_STATS 678 tlb_flush_count++; 679#endif 680 critical_enter(); 681 /* 682 * We need to disable interrupt preemption but MUST NOT have 683 * interrupts disabled here. 684 * XXX we may need to hold schedlock to get a coherent pm_active 685 */ 686 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 687 invltlb(); 688 smp_invltlb(); 689 } else { 690 cpumask = PCPU_GET(cpumask); 691 other_cpus = PCPU_GET(other_cpus); 692 if (pmap->pm_active & cpumask) 693 invltlb(); 694 if (pmap->pm_active & other_cpus) 695 smp_masked_invltlb(pmap->pm_active & other_cpus); 696 } 697 critical_exit(); 698} 699#else /* !SMP */ 700/* 701 * Normal, non-SMP, 486+ invalidation functions. 702 * We inline these within pmap.c for speed. 703 */ 704PMAP_INLINE void 705pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 706{ 707 708 if (pmap == kernel_pmap || pmap->pm_active) 709 invlpg(va); 710} 711 712PMAP_INLINE void 713pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 714{ 715 vm_offset_t addr; 716 717 if (pmap == kernel_pmap || pmap->pm_active) 718 for (addr = sva; addr < eva; addr += PAGE_SIZE) 719 invlpg(addr); 720} 721 722PMAP_INLINE void 723pmap_invalidate_all(pmap_t pmap) 724{ 725 726 if (pmap == kernel_pmap || pmap->pm_active) 727 invltlb(); 728} 729#endif /* !SMP */ 730#endif /* !I386_CPU */ 731 732/* 733 * Return an address which is the base of the Virtual mapping of 734 * all the PTEs for the given pmap. Note this doesn't say that 735 * all the PTEs will be present or that the pages there are valid. 736 * The PTEs are made available by the recursive mapping trick. 737 * It will map in the alternate PTE space if needed. 738 */ 739static pt_entry_t * 740get_ptbase(pmap) 741 pmap_t pmap; 742{ 743 pd_entry_t frame; 744 745 /* are we current address space or kernel? */ 746 if (pmap == kernel_pmap) 747 return PTmap; 748 frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 749 if (frame == (PTDpde & PG_FRAME)) 750 return PTmap; 751 /* otherwise, we are alternate address space */ 752 if (frame != (APTDpde & PG_FRAME)) { 753 APTDpde = (pd_entry_t) (frame | PG_RW | PG_V); 754 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 755 } 756 return APTmap; 757} 758 759/* 760 * Super fast pmap_pte routine best used when scanning 761 * the pv lists. This eliminates many coarse-grained 762 * invltlb calls. Note that many of the pv list 763 * scans are across different pmaps. It is very wasteful 764 * to do an entire invltlb for checking a single mapping. 765 */ 766 767static pt_entry_t * 768pmap_pte_quick(pmap, va) 769 register pmap_t pmap; 770 vm_offset_t va; 771{ 772 pd_entry_t pde, newpf; 773 pde = pmap->pm_pdir[va >> PDRSHIFT]; 774 if (pde != 0) { 775 pd_entry_t frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 776 unsigned index = i386_btop(va); 777 /* are we current address space or kernel? */ 778 if (pmap == kernel_pmap || frame == (PTDpde & PG_FRAME)) 779 return PTmap + index; 780 newpf = pde & PG_FRAME; 781 if (((*PMAP1) & PG_FRAME) != newpf) { 782 *PMAP1 = newpf | PG_RW | PG_V; 783 pmap_invalidate_page(kernel_pmap, (vm_offset_t)PADDR1); 784 } 785 return PADDR1 + (index & (NPTEPG - 1)); 786 } 787 return (0); 788} 789 790/* 791 * Routine: pmap_extract 792 * Function: 793 * Extract the physical page address associated 794 * with the given map/virtual_address pair. 795 */ 796vm_offset_t 797pmap_extract(pmap, va) 798 register pmap_t pmap; 799 vm_offset_t va; 800{ 801 vm_offset_t rtval; /* XXX FIXME */ 802 vm_offset_t pdirindex; 803 804 if (pmap == 0) 805 return 0; 806 pdirindex = va >> PDRSHIFT; 807 rtval = pmap->pm_pdir[pdirindex]; 808 if (rtval != 0) { 809 pt_entry_t *pte; 810 if ((rtval & PG_PS) != 0) { 811 rtval &= ~(NBPDR - 1); 812 rtval |= va & (NBPDR - 1); 813 return rtval; 814 } 815 pte = get_ptbase(pmap) + i386_btop(va); 816 rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); 817 return rtval; 818 } 819 return 0; 820 821} 822 823/*************************************************** 824 * Low level mapping routines..... 825 ***************************************************/ 826 827/* 828 * Add a wired page to the kva. 829 * Note: not SMP coherent. 830 */ 831PMAP_INLINE void 832pmap_kenter(vm_offset_t va, vm_offset_t pa) 833{ 834 pt_entry_t *pte; 835 836 pte = vtopte(va); 837 *pte = pa | PG_RW | PG_V | pgeflag; 838} 839 840/* 841 * Remove a page from the kernel pagetables. 842 * Note: not SMP coherent. 843 */ 844PMAP_INLINE void 845pmap_kremove(vm_offset_t va) 846{ 847 pt_entry_t *pte; 848 849 pte = vtopte(va); 850 *pte = 0; 851} 852 853/* 854 * Used to map a range of physical addresses into kernel 855 * virtual address space. 856 * 857 * The value passed in '*virt' is a suggested virtual address for 858 * the mapping. Architectures which can support a direct-mapped 859 * physical to virtual region can return the appropriate address 860 * within that region, leaving '*virt' unchanged. Other 861 * architectures should map the pages starting at '*virt' and 862 * update '*virt' with the first usable address after the mapped 863 * region. 864 */ 865vm_offset_t 866pmap_map(vm_offset_t *virt, vm_offset_t start, vm_offset_t end, int prot) 867{ 868 vm_offset_t va, sva; 869 870 va = sva = *virt; 871 while (start < end) { 872 pmap_kenter(va, start); 873 va += PAGE_SIZE; 874 start += PAGE_SIZE; 875 } 876 pmap_invalidate_range(kernel_pmap, sva, va); 877 *virt = va; 878 return (sva); 879} 880 881 882/* 883 * Add a list of wired pages to the kva 884 * this routine is only used for temporary 885 * kernel mappings that do not need to have 886 * page modification or references recorded. 887 * Note that old mappings are simply written 888 * over. The page *must* be wired. 889 * Note: SMP coherent. Uses a ranged shootdown IPI. 890 */ 891void 892pmap_qenter(vm_offset_t sva, vm_page_t *m, int count) 893{ 894 vm_offset_t va; 895 896 va = sva; 897 while (count-- > 0) { 898 pmap_kenter(va, VM_PAGE_TO_PHYS(*m)); 899 va += PAGE_SIZE; 900 m++; 901 } 902 pmap_invalidate_range(kernel_pmap, sva, va); 903} 904 905/* 906 * This routine tears out page mappings from the 907 * kernel -- it is meant only for temporary mappings. 908 * Note: SMP coherent. Uses a ranged shootdown IPI. 909 */ 910void 911pmap_qremove(vm_offset_t sva, int count) 912{ 913 vm_offset_t va; 914 915 va = sva; 916 while (count-- > 0) { 917 pmap_kremove(va); 918 va += PAGE_SIZE; 919 } 920 pmap_invalidate_range(kernel_pmap, sva, va); 921} 922 923static vm_page_t 924pmap_page_lookup(vm_object_t object, vm_pindex_t pindex) 925{ 926 vm_page_t m; 927 928retry: 929 m = vm_page_lookup(object, pindex); 930 if (m != NULL) { 931 vm_page_lock_queues(); 932 if (vm_page_sleep_if_busy(m, FALSE, "pplookp")) 933 goto retry; 934 vm_page_unlock_queues(); 935 } 936 return m; 937} 938 939#ifndef KSTACK_MAX_PAGES 940#define KSTACK_MAX_PAGES 32 941#endif 942 943/* 944 * Create the kernel stack (including pcb for i386) for a new thread. 945 * This routine directly affects the fork perf for a process and 946 * create performance for a thread. 947 */ 948void 949pmap_new_thread(struct thread *td, int pages) 950{ 951 int i; 952 vm_page_t ma[KSTACK_MAX_PAGES]; 953 vm_object_t ksobj; 954 vm_page_t m; 955 vm_offset_t ks; 956 957 /* Bounds check */ 958 if (pages <= 1) 959 pages = KSTACK_PAGES; 960 else if (pages > KSTACK_MAX_PAGES) 961 pages = KSTACK_MAX_PAGES; 962 963 /* 964 * allocate object for the kstack 965 */ 966 ksobj = vm_object_allocate(OBJT_DEFAULT, pages); 967 td->td_kstack_obj = ksobj; 968 969 /* get a kernel virtual address for the kstack for this thread */ 970#ifdef KSTACK_GUARD 971 ks = kmem_alloc_nofault(kernel_map, (pages + 1) * PAGE_SIZE); 972 if (ks == 0) 973 panic("pmap_new_thread: kstack allocation failed"); 974 if (*vtopte(ks) != 0) 975 pmap_qremove(ks, 1); 976 ks += PAGE_SIZE; 977 td->td_kstack = ks; 978#else 979 /* get a kernel virtual address for the kstack for this thread */ 980 ks = kmem_alloc_nofault(kernel_map, pages * PAGE_SIZE); 981 if (ks == 0) 982 panic("pmap_new_thread: kstack allocation failed"); 983 td->td_kstack = ks; 984#endif 985 /* 986 * Knowing the number of pages allocated is useful when you 987 * want to deallocate them. 988 */ 989 td->td_kstack_pages = pages; 990 991 /* 992 * For the length of the stack, link in a real page of ram for each 993 * page of stack. 994 */ 995 for (i = 0; i < pages; i++) { 996 /* 997 * Get a kernel stack page 998 */ 999 m = vm_page_grab(ksobj, i, 1000 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED); 1001 ma[i] = m; 1002 1003 vm_page_lock_queues(); 1004 vm_page_wakeup(m); 1005 vm_page_flag_clear(m, PG_ZERO); 1006 m->valid = VM_PAGE_BITS_ALL; 1007 vm_page_unlock_queues(); 1008 } 1009 pmap_qenter(ks, ma, pages); 1010} 1011 1012/* 1013 * Dispose the kernel stack for a thread that has exited. 1014 * This routine directly impacts the exit perf of a process and thread. 1015 */ 1016void 1017pmap_dispose_thread(td) 1018 struct thread *td; 1019{ 1020 int i; 1021 int pages; 1022 vm_object_t ksobj; 1023 vm_offset_t ks; 1024 vm_page_t m; 1025 1026 pages = td->td_kstack_pages; 1027 ksobj = td->td_kstack_obj; 1028 ks = td->td_kstack; 1029 pmap_qremove(ks, pages); 1030 for (i = 0; i < pages; i++) { 1031 m = vm_page_lookup(ksobj, i); 1032 if (m == NULL) 1033 panic("pmap_dispose_thread: kstack already missing?"); 1034 vm_page_lock_queues(); 1035 vm_page_busy(m); 1036 vm_page_unwire(m, 0); 1037 vm_page_free(m); 1038 vm_page_unlock_queues(); 1039 } 1040 /* 1041 * Free the space that this stack was mapped to in the kernel 1042 * address map. 1043 */ 1044#ifdef KSTACK_GUARD 1045 kmem_free(kernel_map, ks - PAGE_SIZE, (pages + 1) * PAGE_SIZE); 1046#else 1047 kmem_free(kernel_map, ks, pages * PAGE_SIZE); 1048#endif 1049 vm_object_deallocate(ksobj); 1050} 1051 1052/* 1053 * Set up a variable sized alternate kstack. Though it may look MI, it may 1054 * need to be different on certain arches like ia64. 1055 */ 1056void 1057pmap_new_altkstack(struct thread *td, int pages) 1058{ 1059 /* shuffle the original stack */ 1060 td->td_altkstack_obj = td->td_kstack_obj; 1061 td->td_altkstack = td->td_kstack; 1062 td->td_altkstack_pages = td->td_kstack_pages; 1063 1064 pmap_new_thread(td, pages); 1065} 1066 1067void 1068pmap_dispose_altkstack(td) 1069 struct thread *td; 1070{ 1071 pmap_dispose_thread(td); 1072 1073 /* restore the original kstack */ 1074 td->td_kstack = td->td_altkstack; 1075 td->td_kstack_obj = td->td_altkstack_obj; 1076 td->td_kstack_pages = td->td_altkstack_pages; 1077 td->td_altkstack = 0; 1078 td->td_altkstack_obj = NULL; 1079 td->td_altkstack_pages = 0; 1080} 1081 1082/* 1083 * Allow the Kernel stack for a thread to be prejudicially paged out. 1084 */ 1085void 1086pmap_swapout_thread(td) 1087 struct thread *td; 1088{ 1089 int i; 1090 int pages; 1091 vm_object_t ksobj; 1092 vm_offset_t ks; 1093 vm_page_t m; 1094 1095 pages = td->td_kstack_pages; 1096 ksobj = td->td_kstack_obj; 1097 ks = td->td_kstack; 1098 pmap_qremove(ks, pages); 1099 for (i = 0; i < pages; i++) { 1100 m = vm_page_lookup(ksobj, i); 1101 if (m == NULL) 1102 panic("pmap_swapout_thread: kstack already missing?"); 1103 vm_page_lock_queues(); 1104 vm_page_dirty(m); 1105 vm_page_unwire(m, 0); 1106 vm_page_unlock_queues(); 1107 } 1108} 1109 1110/* 1111 * Bring the kernel stack for a specified thread back in. 1112 */ 1113void 1114pmap_swapin_thread(td) 1115 struct thread *td; 1116{ 1117 int i, rv; 1118 int pages; 1119 vm_page_t ma[KSTACK_MAX_PAGES]; 1120 vm_object_t ksobj; 1121 vm_offset_t ks; 1122 vm_page_t m; 1123 1124 pages = td->td_kstack_pages; 1125 ksobj = td->td_kstack_obj; 1126 ks = td->td_kstack; 1127 for (i = 0; i < pages; i++) { 1128 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1129 if (m->valid != VM_PAGE_BITS_ALL) { 1130 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1131 if (rv != VM_PAGER_OK) 1132 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1133 m = vm_page_lookup(ksobj, i); 1134 m->valid = VM_PAGE_BITS_ALL; 1135 } 1136 ma[i] = m; 1137 vm_page_lock_queues(); 1138 vm_page_wire(m); 1139 vm_page_wakeup(m); 1140 vm_page_unlock_queues(); 1141 } 1142 pmap_qenter(ks, ma, pages); 1143} 1144 1145/*************************************************** 1146 * Page table page management routines..... 1147 ***************************************************/ 1148 1149/* 1150 * This routine unholds page table pages, and if the hold count 1151 * drops to zero, then it decrements the wire count. 1152 */ 1153static int 1154_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1155{ 1156 1157 while (vm_page_sleep_if_busy(m, FALSE, "pmuwpt")) 1158 vm_page_lock_queues(); 1159 1160 if (m->hold_count == 0) { 1161 vm_offset_t pteva; 1162 /* 1163 * unmap the page table page 1164 */ 1165 pmap->pm_pdir[m->pindex] = 0; 1166 --pmap->pm_stats.resident_count; 1167 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1168 (PTDpde & PG_FRAME)) { 1169 /* 1170 * Do an invltlb to make the invalidated mapping 1171 * take effect immediately. 1172 */ 1173 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); 1174 pmap_invalidate_page(pmap, pteva); 1175 } 1176 1177 if (pmap->pm_ptphint == m) 1178 pmap->pm_ptphint = NULL; 1179 1180 /* 1181 * If the page is finally unwired, simply free it. 1182 */ 1183 --m->wire_count; 1184 if (m->wire_count == 0) { 1185 vm_page_busy(m); 1186 vm_page_free_zero(m); 1187 atomic_subtract_int(&cnt.v_wire_count, 1); 1188 } 1189 return 1; 1190 } 1191 return 0; 1192} 1193 1194static PMAP_INLINE int 1195pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1196{ 1197 vm_page_unhold(m); 1198 if (m->hold_count == 0) 1199 return _pmap_unwire_pte_hold(pmap, m); 1200 else 1201 return 0; 1202} 1203 1204/* 1205 * After removing a page table entry, this routine is used to 1206 * conditionally free the page, and manage the hold/wire counts. 1207 */ 1208static int 1209pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1210{ 1211 unsigned ptepindex; 1212 if (va >= VM_MAXUSER_ADDRESS) 1213 return 0; 1214 1215 if (mpte == NULL) { 1216 ptepindex = (va >> PDRSHIFT); 1217 if (pmap->pm_ptphint && 1218 (pmap->pm_ptphint->pindex == ptepindex)) { 1219 mpte = pmap->pm_ptphint; 1220 } else { 1221 while ((mpte = vm_page_lookup(pmap->pm_pteobj, ptepindex)) != NULL && 1222 vm_page_sleep_if_busy(mpte, FALSE, "pulook")) 1223 vm_page_lock_queues(); 1224 pmap->pm_ptphint = mpte; 1225 } 1226 } 1227 1228 return pmap_unwire_pte_hold(pmap, mpte); 1229} 1230 1231void 1232pmap_pinit0(pmap) 1233 struct pmap *pmap; 1234{ 1235 pmap->pm_pdir = 1236 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1237 pmap_kenter((vm_offset_t)pmap->pm_pdir, (vm_offset_t)IdlePTD); 1238#ifndef I386_CPU 1239 invlpg((vm_offset_t)pmap->pm_pdir); 1240#else 1241 invltlb(); 1242#endif 1243 pmap->pm_ptphint = NULL; 1244 pmap->pm_active = 0; 1245 TAILQ_INIT(&pmap->pm_pvlist); 1246 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1247 mtx_lock_spin(&allpmaps_lock); 1248 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1249 mtx_unlock_spin(&allpmaps_lock); 1250} 1251 1252/* 1253 * Initialize a preallocated and zeroed pmap structure, 1254 * such as one in a vmspace structure. 1255 */ 1256void 1257pmap_pinit(pmap) 1258 register struct pmap *pmap; 1259{ 1260 vm_page_t ptdpg; 1261 1262 /* 1263 * No need to allocate page table space yet but we do need a valid 1264 * page directory table. 1265 */ 1266 if (pmap->pm_pdir == NULL) 1267 pmap->pm_pdir = 1268 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1269 1270 /* 1271 * allocate object for the ptes 1272 */ 1273 if (pmap->pm_pteobj == NULL) 1274 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1275 1276 /* 1277 * allocate the page directory page 1278 */ 1279 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1280 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED | VM_ALLOC_ZERO); 1281 vm_page_lock_queues(); 1282 vm_page_flag_clear(ptdpg, PG_BUSY); 1283 ptdpg->valid = VM_PAGE_BITS_ALL; 1284 vm_page_unlock_queues(); 1285 1286 pmap_qenter((vm_offset_t) pmap->pm_pdir, &ptdpg, 1); 1287 if ((ptdpg->flags & PG_ZERO) == 0) 1288 bzero(pmap->pm_pdir, PAGE_SIZE); 1289 1290 mtx_lock_spin(&allpmaps_lock); 1291 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1292 mtx_unlock_spin(&allpmaps_lock); 1293 /* Wire in kernel global address entries. */ 1294 /* XXX copies current process, does not fill in MPPTDI */ 1295 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1296#ifdef SMP 1297 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1298#endif 1299 1300 /* install self-referential address mapping entry */ 1301 pmap->pm_pdir[PTDPTDI] = 1302 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1303 1304 pmap->pm_active = 0; 1305 pmap->pm_ptphint = NULL; 1306 TAILQ_INIT(&pmap->pm_pvlist); 1307 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1308} 1309 1310/* 1311 * Wire in kernel global address entries. To avoid a race condition 1312 * between pmap initialization and pmap_growkernel, this procedure 1313 * should be called after the vmspace is attached to the process 1314 * but before this pmap is activated. 1315 */ 1316void 1317pmap_pinit2(pmap) 1318 struct pmap *pmap; 1319{ 1320 /* XXX: Remove this stub when no longer called */ 1321} 1322 1323static int 1324pmap_release_free_page(pmap_t pmap, vm_page_t p) 1325{ 1326 pd_entry_t *pde = pmap->pm_pdir; 1327 1328 /* 1329 * This code optimizes the case of freeing non-busy 1330 * page-table pages. Those pages are zero now, and 1331 * might as well be placed directly into the zero queue. 1332 */ 1333 vm_page_lock_queues(); 1334 if (vm_page_sleep_if_busy(p, FALSE, "pmaprl")) 1335 return (0); 1336 vm_page_busy(p); 1337 1338 /* 1339 * Remove the page table page from the processes address space. 1340 */ 1341 pde[p->pindex] = 0; 1342 pmap->pm_stats.resident_count--; 1343 1344 if (p->hold_count) { 1345 panic("pmap_release: freeing held page table page"); 1346 } 1347 /* 1348 * Page directory pages need to have the kernel 1349 * stuff cleared, so they can go into the zero queue also. 1350 */ 1351 if (p->pindex == PTDPTDI) { 1352 bzero(pde + KPTDI, nkpt * PTESIZE); 1353#ifdef SMP 1354 pde[MPPTDI] = 0; 1355#endif 1356 pde[APTDPTDI] = 0; 1357 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1358 } 1359 1360 if (pmap->pm_ptphint == p) 1361 pmap->pm_ptphint = NULL; 1362 1363 p->wire_count--; 1364 atomic_subtract_int(&cnt.v_wire_count, 1); 1365 vm_page_free_zero(p); 1366 vm_page_unlock_queues(); 1367 return 1; 1368} 1369 1370/* 1371 * this routine is called if the page table page is not 1372 * mapped correctly. 1373 */ 1374static vm_page_t 1375_pmap_allocpte(pmap, ptepindex) 1376 pmap_t pmap; 1377 unsigned ptepindex; 1378{ 1379 vm_offset_t pteva, ptepa; /* XXXPA */ 1380 vm_page_t m; 1381 1382 /* 1383 * Find or fabricate a new pagetable page 1384 */ 1385 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1386 VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1387 1388 KASSERT(m->queue == PQ_NONE, 1389 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1390 1391 /* 1392 * Increment the hold count for the page table page 1393 * (denoting a new mapping.) 1394 */ 1395 m->hold_count++; 1396 1397 /* 1398 * Map the pagetable page into the process address space, if 1399 * it isn't already there. 1400 */ 1401 1402 pmap->pm_stats.resident_count++; 1403 1404 ptepa = VM_PAGE_TO_PHYS(m); 1405 pmap->pm_pdir[ptepindex] = 1406 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1407 1408 /* 1409 * Set the page table hint 1410 */ 1411 pmap->pm_ptphint = m; 1412 1413 /* 1414 * Try to use the new mapping, but if we cannot, then 1415 * do it with the routine that maps the page explicitly. 1416 */ 1417 if ((m->flags & PG_ZERO) == 0) { 1418 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1419 (PTDpde & PG_FRAME)) { 1420 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1421 bzero((caddr_t) pteva, PAGE_SIZE); 1422 } else { 1423 pmap_zero_page(m); 1424 } 1425 } 1426 vm_page_lock_queues(); 1427 m->valid = VM_PAGE_BITS_ALL; 1428 vm_page_flag_clear(m, PG_ZERO); 1429 vm_page_wakeup(m); 1430 vm_page_unlock_queues(); 1431 1432 return m; 1433} 1434 1435static vm_page_t 1436pmap_allocpte(pmap_t pmap, vm_offset_t va) 1437{ 1438 unsigned ptepindex; 1439 pd_entry_t ptepa; 1440 vm_page_t m; 1441 1442 /* 1443 * Calculate pagetable page index 1444 */ 1445 ptepindex = va >> PDRSHIFT; 1446 1447 /* 1448 * Get the page directory entry 1449 */ 1450 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1451 1452 /* 1453 * This supports switching from a 4MB page to a 1454 * normal 4K page. 1455 */ 1456 if (ptepa & PG_PS) { 1457 pmap->pm_pdir[ptepindex] = 0; 1458 ptepa = 0; 1459 pmap_invalidate_all(kernel_pmap); 1460 } 1461 1462 /* 1463 * If the page table page is mapped, we just increment the 1464 * hold count, and activate it. 1465 */ 1466 if (ptepa) { 1467 /* 1468 * In order to get the page table page, try the 1469 * hint first. 1470 */ 1471 if (pmap->pm_ptphint && 1472 (pmap->pm_ptphint->pindex == ptepindex)) { 1473 m = pmap->pm_ptphint; 1474 } else { 1475 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1476 pmap->pm_ptphint = m; 1477 } 1478 m->hold_count++; 1479 return m; 1480 } 1481 /* 1482 * Here if the pte page isn't mapped, or if it has been deallocated. 1483 */ 1484 return _pmap_allocpte(pmap, ptepindex); 1485} 1486 1487 1488/*************************************************** 1489* Pmap allocation/deallocation routines. 1490 ***************************************************/ 1491 1492/* 1493 * Release any resources held by the given physical map. 1494 * Called when a pmap initialized by pmap_pinit is being released. 1495 * Should only be called if the map contains no valid mappings. 1496 */ 1497void 1498pmap_release(pmap_t pmap) 1499{ 1500 vm_page_t p,n,ptdpg; 1501 vm_object_t object = pmap->pm_pteobj; 1502 int curgeneration; 1503 1504#if defined(DIAGNOSTIC) 1505 if (object->ref_count != 1) 1506 panic("pmap_release: pteobj reference count != 1"); 1507#endif 1508 1509 ptdpg = NULL; 1510 mtx_lock_spin(&allpmaps_lock); 1511 LIST_REMOVE(pmap, pm_list); 1512 mtx_unlock_spin(&allpmaps_lock); 1513retry: 1514 curgeneration = object->generation; 1515 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1516 n = TAILQ_NEXT(p, listq); 1517 if (p->pindex == PTDPTDI) { 1518 ptdpg = p; 1519 continue; 1520 } 1521 while (1) { 1522 if (!pmap_release_free_page(pmap, p) && 1523 (object->generation != curgeneration)) 1524 goto retry; 1525 } 1526 } 1527 1528 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1529 goto retry; 1530} 1531 1532static int 1533kvm_size(SYSCTL_HANDLER_ARGS) 1534{ 1535 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1536 1537 return sysctl_handle_long(oidp, &ksize, 0, req); 1538} 1539SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1540 0, 0, kvm_size, "IU", "Size of KVM"); 1541 1542static int 1543kvm_free(SYSCTL_HANDLER_ARGS) 1544{ 1545 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1546 1547 return sysctl_handle_long(oidp, &kfree, 0, req); 1548} 1549SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1550 0, 0, kvm_free, "IU", "Amount of KVM free"); 1551 1552/* 1553 * grow the number of kernel page table entries, if needed 1554 */ 1555void 1556pmap_growkernel(vm_offset_t addr) 1557{ 1558 struct pmap *pmap; 1559 int s; 1560 vm_offset_t ptppaddr; 1561 vm_page_t nkpg; 1562 pd_entry_t newpdir; 1563 1564 s = splhigh(); 1565 if (kernel_vm_end == 0) { 1566 kernel_vm_end = KERNBASE; 1567 nkpt = 0; 1568 while (pdir_pde(PTD, kernel_vm_end)) { 1569 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1570 nkpt++; 1571 } 1572 } 1573 addr = roundup2(addr, PAGE_SIZE * NPTEPG); 1574 while (kernel_vm_end < addr) { 1575 if (pdir_pde(PTD, kernel_vm_end)) { 1576 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1577 continue; 1578 } 1579 1580 /* 1581 * This index is bogus, but out of the way 1582 */ 1583 nkpg = vm_page_alloc(kptobj, nkpt, 1584 VM_ALLOC_SYSTEM | VM_ALLOC_WIRED); 1585 if (!nkpg) 1586 panic("pmap_growkernel: no memory to grow kernel"); 1587 1588 nkpt++; 1589 1590 pmap_zero_page(nkpg); 1591 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1592 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1593 pdir_pde(PTD, kernel_vm_end) = newpdir; 1594 1595 mtx_lock_spin(&allpmaps_lock); 1596 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1597 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1598 } 1599 mtx_unlock_spin(&allpmaps_lock); 1600 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1601 } 1602 splx(s); 1603} 1604 1605 1606/*************************************************** 1607 * page management routines. 1608 ***************************************************/ 1609 1610/* 1611 * free the pv_entry back to the free list 1612 */ 1613static PMAP_INLINE void 1614free_pv_entry(pv_entry_t pv) 1615{ 1616 pv_entry_count--; 1617 uma_zfree(pvzone, pv); 1618} 1619 1620/* 1621 * get a new pv_entry, allocating a block from the system 1622 * when needed. 1623 * the memory allocation is performed bypassing the malloc code 1624 * because of the possibility of allocations at interrupt time. 1625 */ 1626static pv_entry_t 1627get_pv_entry(void) 1628{ 1629 pv_entry_count++; 1630 if (pv_entry_high_water && 1631 (pv_entry_count > pv_entry_high_water) && 1632 (pmap_pagedaemon_waken == 0)) { 1633 pmap_pagedaemon_waken = 1; 1634 wakeup (&vm_pages_needed); 1635 } 1636 return uma_zalloc(pvzone, M_NOWAIT); 1637} 1638 1639/* 1640 * If it is the first entry on the list, it is actually 1641 * in the header and we must copy the following entry up 1642 * to the header. Otherwise we must search the list for 1643 * the entry. In either case we free the now unused entry. 1644 */ 1645 1646static int 1647pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1648{ 1649 pv_entry_t pv; 1650 int rtval; 1651 int s; 1652 1653 s = splvm(); 1654 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1655 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1656 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1657 if (pmap == pv->pv_pmap && va == pv->pv_va) 1658 break; 1659 } 1660 } else { 1661 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1662 if (va == pv->pv_va) 1663 break; 1664 } 1665 } 1666 1667 rtval = 0; 1668 if (pv) { 1669 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1670 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1671 m->md.pv_list_count--; 1672 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1673 vm_page_flag_clear(m, PG_WRITEABLE); 1674 1675 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1676 free_pv_entry(pv); 1677 } 1678 1679 splx(s); 1680 return rtval; 1681} 1682 1683/* 1684 * Create a pv entry for page at pa for 1685 * (pmap, va). 1686 */ 1687static void 1688pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1689{ 1690 1691 int s; 1692 pv_entry_t pv; 1693 1694 s = splvm(); 1695 pv = get_pv_entry(); 1696 pv->pv_va = va; 1697 pv->pv_pmap = pmap; 1698 pv->pv_ptem = mpte; 1699 1700 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1701 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1702 m->md.pv_list_count++; 1703 1704 splx(s); 1705} 1706 1707/* 1708 * pmap_remove_pte: do the things to unmap a page in a process 1709 */ 1710static int 1711pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1712{ 1713 pt_entry_t oldpte; 1714 vm_page_t m; 1715 1716 oldpte = atomic_readandclear_int(ptq); 1717 if (oldpte & PG_W) 1718 pmap->pm_stats.wired_count -= 1; 1719 /* 1720 * Machines that don't support invlpg, also don't support 1721 * PG_G. 1722 */ 1723 if (oldpte & PG_G) 1724 pmap_invalidate_page(kernel_pmap, va); 1725 pmap->pm_stats.resident_count -= 1; 1726 if (oldpte & PG_MANAGED) { 1727 m = PHYS_TO_VM_PAGE(oldpte); 1728 if (oldpte & PG_M) { 1729#if defined(PMAP_DIAGNOSTIC) 1730 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1731 printf( 1732 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1733 va, oldpte); 1734 } 1735#endif 1736 if (pmap_track_modified(va)) 1737 vm_page_dirty(m); 1738 } 1739 if (oldpte & PG_A) 1740 vm_page_flag_set(m, PG_REFERENCED); 1741 return pmap_remove_entry(pmap, m, va); 1742 } else { 1743 return pmap_unuse_pt(pmap, va, NULL); 1744 } 1745 1746 return 0; 1747} 1748 1749/* 1750 * Remove a single page from a process address space 1751 */ 1752static void 1753pmap_remove_page(pmap_t pmap, vm_offset_t va) 1754{ 1755 register pt_entry_t *ptq; 1756 1757 /* 1758 * if there is no pte for this address, just skip it!!! 1759 */ 1760 if (*pmap_pde(pmap, va) == 0) { 1761 return; 1762 } 1763 1764 /* 1765 * get a local va for mappings for this pmap. 1766 */ 1767 ptq = get_ptbase(pmap) + i386_btop(va); 1768 if (*ptq) { 1769 (void) pmap_remove_pte(pmap, ptq, va); 1770 pmap_invalidate_page(pmap, va); 1771 } 1772 return; 1773} 1774 1775/* 1776 * Remove the given range of addresses from the specified map. 1777 * 1778 * It is assumed that the start and end are properly 1779 * rounded to the page size. 1780 */ 1781void 1782pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1783{ 1784 register pt_entry_t *ptbase; 1785 vm_offset_t pdnxt; 1786 pd_entry_t ptpaddr; 1787 vm_offset_t sindex, eindex; 1788 int anyvalid; 1789 1790 if (pmap == NULL) 1791 return; 1792 1793 if (pmap->pm_stats.resident_count == 0) 1794 return; 1795 1796 /* 1797 * special handling of removing one page. a very 1798 * common operation and easy to short circuit some 1799 * code. 1800 */ 1801 if ((sva + PAGE_SIZE == eva) && 1802 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1803 pmap_remove_page(pmap, sva); 1804 return; 1805 } 1806 1807 anyvalid = 0; 1808 1809 /* 1810 * Get a local virtual address for the mappings that are being 1811 * worked with. 1812 */ 1813 ptbase = get_ptbase(pmap); 1814 1815 sindex = i386_btop(sva); 1816 eindex = i386_btop(eva); 1817 1818 for (; sindex < eindex; sindex = pdnxt) { 1819 unsigned pdirindex; 1820 1821 /* 1822 * Calculate index for next page table. 1823 */ 1824 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1825 if (pmap->pm_stats.resident_count == 0) 1826 break; 1827 1828 pdirindex = sindex / NPDEPG; 1829 ptpaddr = pmap->pm_pdir[pdirindex]; 1830 if ((ptpaddr & PG_PS) != 0) { 1831 pmap->pm_pdir[pdirindex] = 0; 1832 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1833 anyvalid++; 1834 continue; 1835 } 1836 1837 /* 1838 * Weed out invalid mappings. Note: we assume that the page 1839 * directory table is always allocated, and in kernel virtual. 1840 */ 1841 if (ptpaddr == 0) 1842 continue; 1843 1844 /* 1845 * Limit our scan to either the end of the va represented 1846 * by the current page table page, or to the end of the 1847 * range being removed. 1848 */ 1849 if (pdnxt > eindex) { 1850 pdnxt = eindex; 1851 } 1852 1853 for (; sindex != pdnxt; sindex++) { 1854 vm_offset_t va; 1855 if (ptbase[sindex] == 0) { 1856 continue; 1857 } 1858 va = i386_ptob(sindex); 1859 1860 anyvalid++; 1861 if (pmap_remove_pte(pmap, ptbase + sindex, va)) 1862 break; 1863 } 1864 } 1865 1866 if (anyvalid) 1867 pmap_invalidate_all(pmap); 1868} 1869 1870/* 1871 * Routine: pmap_remove_all 1872 * Function: 1873 * Removes this physical page from 1874 * all physical maps in which it resides. 1875 * Reflects back modify bits to the pager. 1876 * 1877 * Notes: 1878 * Original versions of this routine were very 1879 * inefficient because they iteratively called 1880 * pmap_remove (slow...) 1881 */ 1882 1883void 1884pmap_remove_all(vm_page_t m) 1885{ 1886 register pv_entry_t pv; 1887 pt_entry_t *pte, tpte; 1888 int s; 1889 1890#if defined(PMAP_DIAGNOSTIC) 1891 /* 1892 * XXX This makes pmap_remove_all() illegal for non-managed pages! 1893 */ 1894 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1895 panic("pmap_remove_all: illegal for unmanaged page, va: 0x%x", 1896 VM_PAGE_TO_PHYS(m)); 1897 } 1898#endif 1899 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1900 s = splvm(); 1901 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1902 pv->pv_pmap->pm_stats.resident_count--; 1903 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1904 tpte = atomic_readandclear_int(pte); 1905 if (tpte & PG_W) 1906 pv->pv_pmap->pm_stats.wired_count--; 1907 if (tpte & PG_A) 1908 vm_page_flag_set(m, PG_REFERENCED); 1909 1910 /* 1911 * Update the vm_page_t clean and reference bits. 1912 */ 1913 if (tpte & PG_M) { 1914#if defined(PMAP_DIAGNOSTIC) 1915 if (pmap_nw_modified((pt_entry_t) tpte)) { 1916 printf( 1917 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1918 pv->pv_va, tpte); 1919 } 1920#endif 1921 if (pmap_track_modified(pv->pv_va)) 1922 vm_page_dirty(m); 1923 } 1924 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1925 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1926 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1927 m->md.pv_list_count--; 1928 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1929 free_pv_entry(pv); 1930 } 1931 vm_page_flag_clear(m, PG_WRITEABLE); 1932 splx(s); 1933} 1934 1935/* 1936 * Set the physical protection on the 1937 * specified range of this map as requested. 1938 */ 1939void 1940pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1941{ 1942 register pt_entry_t *ptbase; 1943 vm_offset_t pdnxt; 1944 pd_entry_t ptpaddr; 1945 vm_offset_t sindex, eindex; 1946 int anychanged; 1947 1948 if (pmap == NULL) 1949 return; 1950 1951 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1952 pmap_remove(pmap, sva, eva); 1953 return; 1954 } 1955 1956 if (prot & VM_PROT_WRITE) 1957 return; 1958 1959 anychanged = 0; 1960 1961 ptbase = get_ptbase(pmap); 1962 1963 sindex = i386_btop(sva); 1964 eindex = i386_btop(eva); 1965 1966 for (; sindex < eindex; sindex = pdnxt) { 1967 1968 unsigned pdirindex; 1969 1970 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1971 1972 pdirindex = sindex / NPDEPG; 1973 ptpaddr = pmap->pm_pdir[pdirindex]; 1974 if ((ptpaddr & PG_PS) != 0) { 1975 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1976 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1977 anychanged++; 1978 continue; 1979 } 1980 1981 /* 1982 * Weed out invalid mappings. Note: we assume that the page 1983 * directory table is always allocated, and in kernel virtual. 1984 */ 1985 if (ptpaddr == 0) 1986 continue; 1987 1988 if (pdnxt > eindex) { 1989 pdnxt = eindex; 1990 } 1991 1992 for (; sindex != pdnxt; sindex++) { 1993 1994 pt_entry_t pbits; 1995 vm_page_t m; 1996 1997 pbits = ptbase[sindex]; 1998 1999 if (pbits & PG_MANAGED) { 2000 m = NULL; 2001 if (pbits & PG_A) { 2002 m = PHYS_TO_VM_PAGE(pbits); 2003 vm_page_flag_set(m, PG_REFERENCED); 2004 pbits &= ~PG_A; 2005 } 2006 if (pbits & PG_M) { 2007 if (pmap_track_modified(i386_ptob(sindex))) { 2008 if (m == NULL) 2009 m = PHYS_TO_VM_PAGE(pbits); 2010 vm_page_dirty(m); 2011 pbits &= ~PG_M; 2012 } 2013 } 2014 } 2015 2016 pbits &= ~PG_RW; 2017 2018 if (pbits != ptbase[sindex]) { 2019 ptbase[sindex] = pbits; 2020 anychanged = 1; 2021 } 2022 } 2023 } 2024 if (anychanged) 2025 pmap_invalidate_all(pmap); 2026} 2027 2028/* 2029 * Insert the given physical page (p) at 2030 * the specified virtual address (v) in the 2031 * target physical map with the protection requested. 2032 * 2033 * If specified, the page will be wired down, meaning 2034 * that the related pte can not be reclaimed. 2035 * 2036 * NB: This is the only routine which MAY NOT lazy-evaluate 2037 * or lose information. That is, this routine must actually 2038 * insert this page into the given map NOW. 2039 */ 2040void 2041pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2042 boolean_t wired) 2043{ 2044 vm_offset_t pa; 2045 register pt_entry_t *pte; 2046 vm_offset_t opa; 2047 pt_entry_t origpte, newpte; 2048 vm_page_t mpte; 2049 2050 if (pmap == NULL) 2051 return; 2052 2053 va &= PG_FRAME; 2054#ifdef PMAP_DIAGNOSTIC 2055 if (va > VM_MAX_KERNEL_ADDRESS) 2056 panic("pmap_enter: toobig"); 2057 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2058 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2059#endif 2060 2061 mpte = NULL; 2062 /* 2063 * In the case that a page table page is not 2064 * resident, we are creating it here. 2065 */ 2066 if (va < VM_MAXUSER_ADDRESS) { 2067 mpte = pmap_allocpte(pmap, va); 2068 } 2069#if 0 && defined(PMAP_DIAGNOSTIC) 2070 else { 2071 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2072 origpte = *pdeaddr; 2073 if ((origpte & PG_V) == 0) { 2074 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2075 pmap->pm_pdir[PTDPTDI], origpte, va); 2076 } 2077 } 2078#endif 2079 2080 pte = pmap_pte(pmap, va); 2081 2082 /* 2083 * Page Directory table entry not valid, we need a new PT page 2084 */ 2085 if (pte == NULL) { 2086 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2087 (void *)pmap->pm_pdir[PTDPTDI], va); 2088 } 2089 2090 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2091 origpte = *(vm_offset_t *)pte; 2092 opa = origpte & PG_FRAME; 2093 2094 if (origpte & PG_PS) 2095 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2096 2097 /* 2098 * Mapping has not changed, must be protection or wiring change. 2099 */ 2100 if (origpte && (opa == pa)) { 2101 /* 2102 * Wiring change, just update stats. We don't worry about 2103 * wiring PT pages as they remain resident as long as there 2104 * are valid mappings in them. Hence, if a user page is wired, 2105 * the PT page will be also. 2106 */ 2107 if (wired && ((origpte & PG_W) == 0)) 2108 pmap->pm_stats.wired_count++; 2109 else if (!wired && (origpte & PG_W)) 2110 pmap->pm_stats.wired_count--; 2111 2112#if defined(PMAP_DIAGNOSTIC) 2113 if (pmap_nw_modified((pt_entry_t) origpte)) { 2114 printf( 2115 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2116 va, origpte); 2117 } 2118#endif 2119 2120 /* 2121 * Remove extra pte reference 2122 */ 2123 if (mpte) 2124 mpte->hold_count--; 2125 2126 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2127 if ((origpte & PG_RW) == 0) { 2128 *pte |= PG_RW; 2129 pmap_invalidate_page(pmap, va); 2130 } 2131 return; 2132 } 2133 2134 /* 2135 * We might be turning off write access to the page, 2136 * so we go ahead and sense modify status. 2137 */ 2138 if (origpte & PG_MANAGED) { 2139 if ((origpte & PG_M) && pmap_track_modified(va)) { 2140 vm_page_t om; 2141 om = PHYS_TO_VM_PAGE(opa); 2142 vm_page_dirty(om); 2143 } 2144 pa |= PG_MANAGED; 2145 } 2146 goto validate; 2147 } 2148 /* 2149 * Mapping has changed, invalidate old range and fall through to 2150 * handle validating new mapping. 2151 */ 2152 if (opa) { 2153 int err; 2154 vm_page_lock_queues(); 2155 err = pmap_remove_pte(pmap, pte, va); 2156 vm_page_unlock_queues(); 2157 if (err) 2158 panic("pmap_enter: pte vanished, va: 0x%x", va); 2159 } 2160 2161 /* 2162 * Enter on the PV list if part of our managed memory. Note that we 2163 * raise IPL while manipulating pv_table since pmap_enter can be 2164 * called at interrupt time. 2165 */ 2166 if (pmap_initialized && 2167 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2168 pmap_insert_entry(pmap, va, mpte, m); 2169 pa |= PG_MANAGED; 2170 } 2171 2172 /* 2173 * Increment counters 2174 */ 2175 pmap->pm_stats.resident_count++; 2176 if (wired) 2177 pmap->pm_stats.wired_count++; 2178 2179validate: 2180 /* 2181 * Now validate mapping with desired protection/wiring. 2182 */ 2183 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2184 2185 if (wired) 2186 newpte |= PG_W; 2187 if (va < VM_MAXUSER_ADDRESS) 2188 newpte |= PG_U; 2189 if (pmap == kernel_pmap) 2190 newpte |= pgeflag; 2191 2192 /* 2193 * if the mapping or permission bits are different, we need 2194 * to update the pte. 2195 */ 2196 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2197 *pte = newpte | PG_A; 2198 /*if (origpte)*/ { 2199 pmap_invalidate_page(pmap, va); 2200 } 2201 } 2202} 2203 2204/* 2205 * this code makes some *MAJOR* assumptions: 2206 * 1. Current pmap & pmap exists. 2207 * 2. Not wired. 2208 * 3. Read access. 2209 * 4. No page table pages. 2210 * 5. Tlbflush is deferred to calling procedure. 2211 * 6. Page IS managed. 2212 * but is *MUCH* faster than pmap_enter... 2213 */ 2214 2215static vm_page_t 2216pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2217{ 2218 pt_entry_t *pte; 2219 vm_offset_t pa; 2220 2221 /* 2222 * In the case that a page table page is not 2223 * resident, we are creating it here. 2224 */ 2225 if (va < VM_MAXUSER_ADDRESS) { 2226 unsigned ptepindex; 2227 pd_entry_t ptepa; 2228 2229 /* 2230 * Calculate pagetable page index 2231 */ 2232 ptepindex = va >> PDRSHIFT; 2233 if (mpte && (mpte->pindex == ptepindex)) { 2234 mpte->hold_count++; 2235 } else { 2236retry: 2237 /* 2238 * Get the page directory entry 2239 */ 2240 ptepa = pmap->pm_pdir[ptepindex]; 2241 2242 /* 2243 * If the page table page is mapped, we just increment 2244 * the hold count, and activate it. 2245 */ 2246 if (ptepa) { 2247 if (ptepa & PG_PS) 2248 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2249 if (pmap->pm_ptphint && 2250 (pmap->pm_ptphint->pindex == ptepindex)) { 2251 mpte = pmap->pm_ptphint; 2252 } else { 2253 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2254 pmap->pm_ptphint = mpte; 2255 } 2256 if (mpte == NULL) 2257 goto retry; 2258 mpte->hold_count++; 2259 } else { 2260 mpte = _pmap_allocpte(pmap, ptepindex); 2261 } 2262 } 2263 } else { 2264 mpte = NULL; 2265 } 2266 2267 /* 2268 * This call to vtopte makes the assumption that we are 2269 * entering the page into the current pmap. In order to support 2270 * quick entry into any pmap, one would likely use pmap_pte_quick. 2271 * But that isn't as quick as vtopte. 2272 */ 2273 pte = vtopte(va); 2274 if (*pte) { 2275 if (mpte != NULL) { 2276 vm_page_lock_queues(); 2277 pmap_unwire_pte_hold(pmap, mpte); 2278 vm_page_unlock_queues(); 2279 } 2280 return 0; 2281 } 2282 2283 /* 2284 * Enter on the PV list if part of our managed memory. Note that we 2285 * raise IPL while manipulating pv_table since pmap_enter can be 2286 * called at interrupt time. 2287 */ 2288 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2289 pmap_insert_entry(pmap, va, mpte, m); 2290 2291 /* 2292 * Increment counters 2293 */ 2294 pmap->pm_stats.resident_count++; 2295 2296 pa = VM_PAGE_TO_PHYS(m); 2297 2298 /* 2299 * Now validate mapping with RO protection 2300 */ 2301 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2302 *pte = pa | PG_V | PG_U; 2303 else 2304 *pte = pa | PG_V | PG_U | PG_MANAGED; 2305 2306 return mpte; 2307} 2308 2309/* 2310 * Make a temporary mapping for a physical address. This is only intended 2311 * to be used for panic dumps. 2312 */ 2313void * 2314pmap_kenter_temporary(vm_offset_t pa, int i) 2315{ 2316 vm_offset_t va; 2317 2318 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE); 2319 pmap_kenter(va, pa); 2320#ifndef I386_CPU 2321 invlpg(va); 2322#else 2323 invltlb(); 2324#endif 2325 return ((void *)crashdumpmap); 2326} 2327 2328#define MAX_INIT_PT (96) 2329/* 2330 * pmap_object_init_pt preloads the ptes for a given object 2331 * into the specified pmap. This eliminates the blast of soft 2332 * faults on process startup and immediately after an mmap. 2333 */ 2334void 2335pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2336 vm_object_t object, vm_pindex_t pindex, 2337 vm_size_t size, int limit) 2338{ 2339 vm_offset_t tmpidx; 2340 int psize; 2341 vm_page_t p, mpte; 2342 2343 if (pmap == NULL || object == NULL) 2344 return; 2345 2346 /* 2347 * This code maps large physical mmap regions into the 2348 * processor address space. Note that some shortcuts 2349 * are taken, but the code works. 2350 */ 2351 if (pseflag && (object->type == OBJT_DEVICE) && 2352 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2353 int i; 2354 vm_page_t m[1]; 2355 unsigned int ptepindex; 2356 int npdes; 2357 pd_entry_t ptepa; 2358 2359 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2360 return; 2361 2362retry: 2363 p = vm_page_lookup(object, pindex); 2364 if (p != NULL) { 2365 vm_page_lock_queues(); 2366 if (vm_page_sleep_if_busy(p, FALSE, "init4p")) 2367 goto retry; 2368 } else { 2369 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2370 if (p == NULL) 2371 return; 2372 m[0] = p; 2373 2374 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2375 vm_page_lock_queues(); 2376 vm_page_free(p); 2377 vm_page_unlock_queues(); 2378 return; 2379 } 2380 2381 p = vm_page_lookup(object, pindex); 2382 vm_page_lock_queues(); 2383 vm_page_wakeup(p); 2384 } 2385 vm_page_unlock_queues(); 2386 2387 ptepa = VM_PAGE_TO_PHYS(p); 2388 if (ptepa & (NBPDR - 1)) { 2389 return; 2390 } 2391 2392 p->valid = VM_PAGE_BITS_ALL; 2393 2394 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2395 npdes = size >> PDRSHIFT; 2396 for(i = 0; i < npdes; i++) { 2397 pmap->pm_pdir[ptepindex] = 2398 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2399 ptepa += NBPDR; 2400 ptepindex += 1; 2401 } 2402 pmap_invalidate_all(kernel_pmap); 2403 return; 2404 } 2405 2406 psize = i386_btop(size); 2407 2408 if ((object->type != OBJT_VNODE) || 2409 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2410 (object->resident_page_count > MAX_INIT_PT))) { 2411 return; 2412 } 2413 2414 if (psize + pindex > object->size) { 2415 if (object->size < pindex) 2416 return; 2417 psize = object->size - pindex; 2418 } 2419 2420 mpte = NULL; 2421 2422 if ((p = TAILQ_FIRST(&object->memq)) != NULL) { 2423 if (p->pindex < pindex) { 2424 p = vm_page_splay(pindex, object->root); 2425 if ((object->root = p)->pindex < pindex) 2426 p = TAILQ_NEXT(p, listq); 2427 } 2428 } 2429 /* 2430 * Assert: the variable p is either (1) the page with the 2431 * least pindex greater than or equal to the parameter pindex 2432 * or (2) NULL. 2433 */ 2434 for (; 2435 p != NULL && (tmpidx = p->pindex - pindex) < psize; 2436 p = TAILQ_NEXT(p, listq)) { 2437 /* 2438 * don't allow an madvise to blow away our really 2439 * free pages allocating pv entries. 2440 */ 2441 if ((limit & MAP_PREFAULT_MADVISE) && 2442 cnt.v_free_count < cnt.v_free_reserved) { 2443 break; 2444 } 2445 vm_page_lock_queues(); 2446 if ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL && 2447 (p->busy == 0) && 2448 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2449 if ((p->queue - p->pc) == PQ_CACHE) 2450 vm_page_deactivate(p); 2451 vm_page_busy(p); 2452 vm_page_unlock_queues(); 2453 mpte = pmap_enter_quick(pmap, 2454 addr + i386_ptob(tmpidx), p, mpte); 2455 vm_page_lock_queues(); 2456 vm_page_wakeup(p); 2457 } 2458 vm_page_unlock_queues(); 2459 } 2460 return; 2461} 2462 2463/* 2464 * pmap_prefault provides a quick way of clustering 2465 * pagefaults into a processes address space. It is a "cousin" 2466 * of pmap_object_init_pt, except it runs at page fault time instead 2467 * of mmap time. 2468 */ 2469#define PFBAK 4 2470#define PFFOR 4 2471#define PAGEORDER_SIZE (PFBAK+PFFOR) 2472 2473static int pmap_prefault_pageorder[] = { 2474 -1 * PAGE_SIZE, 1 * PAGE_SIZE, 2475 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2476 -3 * PAGE_SIZE, 3 * PAGE_SIZE, 2477 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2478}; 2479 2480void 2481pmap_prefault(pmap, addra, entry) 2482 pmap_t pmap; 2483 vm_offset_t addra; 2484 vm_map_entry_t entry; 2485{ 2486 int i; 2487 vm_offset_t starta; 2488 vm_offset_t addr; 2489 vm_pindex_t pindex; 2490 vm_page_t m, mpte; 2491 vm_object_t object; 2492 2493 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2494 return; 2495 2496 object = entry->object.vm_object; 2497 2498 starta = addra - PFBAK * PAGE_SIZE; 2499 if (starta < entry->start) { 2500 starta = entry->start; 2501 } else if (starta > addra) { 2502 starta = 0; 2503 } 2504 2505 mpte = NULL; 2506 for (i = 0; i < PAGEORDER_SIZE; i++) { 2507 vm_object_t lobject; 2508 pt_entry_t *pte; 2509 2510 addr = addra + pmap_prefault_pageorder[i]; 2511 if (addr > addra + (PFFOR * PAGE_SIZE)) 2512 addr = 0; 2513 2514 if (addr < starta || addr >= entry->end) 2515 continue; 2516 2517 if ((*pmap_pde(pmap, addr)) == 0) 2518 continue; 2519 2520 pte = vtopte(addr); 2521 if (*pte) 2522 continue; 2523 2524 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2525 lobject = object; 2526 for (m = vm_page_lookup(lobject, pindex); 2527 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2528 lobject = lobject->backing_object) { 2529 if (lobject->backing_object_offset & PAGE_MASK) 2530 break; 2531 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2532 m = vm_page_lookup(lobject->backing_object, pindex); 2533 } 2534 2535 /* 2536 * give-up when a page is not in memory 2537 */ 2538 if (m == NULL) 2539 break; 2540 vm_page_lock_queues(); 2541 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2542 (m->busy == 0) && 2543 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2544 2545 if ((m->queue - m->pc) == PQ_CACHE) { 2546 vm_page_deactivate(m); 2547 } 2548 vm_page_busy(m); 2549 vm_page_unlock_queues(); 2550 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2551 vm_page_lock_queues(); 2552 vm_page_wakeup(m); 2553 } 2554 vm_page_unlock_queues(); 2555 } 2556} 2557 2558/* 2559 * Routine: pmap_change_wiring 2560 * Function: Change the wiring attribute for a map/virtual-address 2561 * pair. 2562 * In/out conditions: 2563 * The mapping must already exist in the pmap. 2564 */ 2565void 2566pmap_change_wiring(pmap, va, wired) 2567 register pmap_t pmap; 2568 vm_offset_t va; 2569 boolean_t wired; 2570{ 2571 register pt_entry_t *pte; 2572 2573 if (pmap == NULL) 2574 return; 2575 2576 pte = pmap_pte(pmap, va); 2577 2578 if (wired && !pmap_pte_w(pte)) 2579 pmap->pm_stats.wired_count++; 2580 else if (!wired && pmap_pte_w(pte)) 2581 pmap->pm_stats.wired_count--; 2582 2583 /* 2584 * Wiring is not a hardware characteristic so there is no need to 2585 * invalidate TLB. 2586 */ 2587 pmap_pte_set_w(pte, wired); 2588} 2589 2590 2591 2592/* 2593 * Copy the range specified by src_addr/len 2594 * from the source map to the range dst_addr/len 2595 * in the destination map. 2596 * 2597 * This routine is only advisory and need not do anything. 2598 */ 2599 2600void 2601pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2602 vm_offset_t src_addr) 2603{ 2604 vm_offset_t addr; 2605 vm_offset_t end_addr = src_addr + len; 2606 vm_offset_t pdnxt; 2607 pd_entry_t src_frame, dst_frame; 2608 vm_page_t m; 2609 2610 if (dst_addr != src_addr) 2611 return; 2612 2613 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2614 if (src_frame != (PTDpde & PG_FRAME)) 2615 return; 2616 2617 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2618 for (addr = src_addr; addr < end_addr; addr = pdnxt) { 2619 pt_entry_t *src_pte, *dst_pte; 2620 vm_page_t dstmpte, srcmpte; 2621 pd_entry_t srcptepaddr; 2622 unsigned ptepindex; 2623 2624 if (addr >= UPT_MIN_ADDRESS) 2625 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2626 2627 /* 2628 * Don't let optional prefaulting of pages make us go 2629 * way below the low water mark of free pages or way 2630 * above high water mark of used pv entries. 2631 */ 2632 if (cnt.v_free_count < cnt.v_free_reserved || 2633 pv_entry_count > pv_entry_high_water) 2634 break; 2635 2636 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2637 ptepindex = addr >> PDRSHIFT; 2638 2639 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2640 if (srcptepaddr == 0) 2641 continue; 2642 2643 if (srcptepaddr & PG_PS) { 2644 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2645 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2646 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2647 } 2648 continue; 2649 } 2650 2651 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2652 if ((srcmpte == NULL) || 2653 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2654 continue; 2655 2656 if (pdnxt > end_addr) 2657 pdnxt = end_addr; 2658 2659 /* 2660 * Have to recheck this before every avtopte() call below 2661 * in case we have blocked and something else used APTDpde. 2662 */ 2663 if (dst_frame != (APTDpde & PG_FRAME)) { 2664 APTDpde = dst_frame | PG_RW | PG_V; 2665 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 2666 } 2667 src_pte = vtopte(addr); 2668 dst_pte = avtopte(addr); 2669 while (addr < pdnxt) { 2670 pt_entry_t ptetemp; 2671 ptetemp = *src_pte; 2672 /* 2673 * we only virtual copy managed pages 2674 */ 2675 if ((ptetemp & PG_MANAGED) != 0) { 2676 /* 2677 * We have to check after allocpte for the 2678 * pte still being around... allocpte can 2679 * block. 2680 */ 2681 dstmpte = pmap_allocpte(dst_pmap, addr); 2682 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2683 /* 2684 * Clear the modified and 2685 * accessed (referenced) bits 2686 * during the copy. 2687 */ 2688 m = PHYS_TO_VM_PAGE(ptetemp); 2689 *dst_pte = ptetemp & ~(PG_M | PG_A); 2690 dst_pmap->pm_stats.resident_count++; 2691 pmap_insert_entry(dst_pmap, addr, 2692 dstmpte, m); 2693 } else { 2694 vm_page_lock_queues(); 2695 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2696 vm_page_unlock_queues(); 2697 } 2698 if (dstmpte->hold_count >= srcmpte->hold_count) 2699 break; 2700 } 2701 addr += PAGE_SIZE; 2702 src_pte++; 2703 dst_pte++; 2704 } 2705 } 2706} 2707 2708#ifdef SMP 2709 2710/* 2711 * pmap_zpi_switchin*() 2712 * 2713 * These functions allow us to avoid doing IPIs alltogether in certain 2714 * temporary page-mapping situations (page zeroing). Instead to deal 2715 * with being preempted and moved onto a different cpu we invalidate 2716 * the page when the scheduler switches us in. This does not occur 2717 * very often so we remain relatively optimal with very little effort. 2718 */ 2719static void 2720pmap_zpi_switchin12(void) 2721{ 2722 invlpg((u_int)CADDR1); 2723 invlpg((u_int)CADDR2); 2724} 2725 2726static void 2727pmap_zpi_switchin2(void) 2728{ 2729 invlpg((u_int)CADDR2); 2730} 2731 2732static void 2733pmap_zpi_switchin3(void) 2734{ 2735 invlpg((u_int)CADDR3); 2736} 2737 2738#endif 2739 2740/* 2741 * pmap_zero_page zeros the specified hardware page by mapping 2742 * the page into KVM and using bzero to clear its contents. 2743 */ 2744void 2745pmap_zero_page(vm_page_t m) 2746{ 2747 vm_offset_t phys; 2748 2749 phys = VM_PAGE_TO_PHYS(m); 2750 if (*CMAP2) 2751 panic("pmap_zero_page: CMAP2 busy"); 2752 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2753#ifdef I386_CPU 2754 invltlb(); 2755#else 2756#ifdef SMP 2757 curthread->td_switchin = pmap_zpi_switchin2; 2758#endif 2759 invlpg((u_int)CADDR2); 2760#endif 2761#if defined(I686_CPU) 2762 if (cpu_class == CPUCLASS_686) 2763 i686_pagezero(CADDR2); 2764 else 2765#endif 2766 bzero(CADDR2, PAGE_SIZE); 2767#ifdef SMP 2768 curthread->td_switchin = NULL; 2769#endif 2770 *CMAP2 = 0; 2771} 2772 2773/* 2774 * pmap_zero_page_area zeros the specified hardware page by mapping 2775 * the page into KVM and using bzero to clear its contents. 2776 * 2777 * off and size may not cover an area beyond a single hardware page. 2778 */ 2779void 2780pmap_zero_page_area(vm_page_t m, int off, int size) 2781{ 2782 vm_offset_t phys; 2783 2784 phys = VM_PAGE_TO_PHYS(m); 2785 if (*CMAP2) 2786 panic("pmap_zero_page: CMAP2 busy"); 2787 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2788#ifdef I386_CPU 2789 invltlb(); 2790#else 2791#ifdef SMP 2792 curthread->td_switchin = pmap_zpi_switchin2; 2793#endif 2794 invlpg((u_int)CADDR2); 2795#endif 2796#if defined(I686_CPU) 2797 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2798 i686_pagezero(CADDR2); 2799 else 2800#endif 2801 bzero((char *)CADDR2 + off, size); 2802#ifdef SMP 2803 curthread->td_switchin = NULL; 2804#endif 2805 *CMAP2 = 0; 2806} 2807 2808/* 2809 * pmap_zero_page_idle zeros the specified hardware page by mapping 2810 * the page into KVM and using bzero to clear its contents. This 2811 * is intended to be called from the vm_pagezero process only and 2812 * outside of Giant. 2813 */ 2814void 2815pmap_zero_page_idle(vm_page_t m) 2816{ 2817 vm_offset_t phys; 2818 2819 phys = VM_PAGE_TO_PHYS(m); 2820 if (*CMAP3) 2821 panic("pmap_zero_page: CMAP3 busy"); 2822 *CMAP3 = PG_V | PG_RW | phys | PG_A | PG_M; 2823#ifdef I386_CPU 2824 invltlb(); 2825#else 2826#ifdef SMP 2827 curthread->td_switchin = pmap_zpi_switchin3; 2828#endif 2829 invlpg((u_int)CADDR3); 2830#endif 2831#if defined(I686_CPU) 2832 if (cpu_class == CPUCLASS_686) 2833 i686_pagezero(CADDR3); 2834 else 2835#endif 2836 bzero(CADDR3, PAGE_SIZE); 2837#ifdef SMP 2838 curthread->td_switchin = NULL; 2839#endif 2840 *CMAP3 = 0; 2841} 2842 2843/* 2844 * pmap_copy_page copies the specified (machine independent) 2845 * page by mapping the page into virtual memory and using 2846 * bcopy to copy the page, one machine dependent page at a 2847 * time. 2848 */ 2849void 2850pmap_copy_page(vm_page_t src, vm_page_t dst) 2851{ 2852 2853 if (*CMAP1) 2854 panic("pmap_copy_page: CMAP1 busy"); 2855 if (*CMAP2) 2856 panic("pmap_copy_page: CMAP2 busy"); 2857 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2858 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2859#ifdef I386_CPU 2860 invltlb(); 2861#else 2862#ifdef SMP 2863 curthread->td_switchin = pmap_zpi_switchin12; 2864#endif 2865 invlpg((u_int)CADDR1); 2866 invlpg((u_int)CADDR2); 2867#endif 2868 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2869#ifdef SMP 2870 curthread->td_switchin = NULL; 2871#endif 2872 *CMAP1 = 0; 2873 *CMAP2 = 0; 2874} 2875 2876/* 2877 * Returns true if the pmap's pv is one of the first 2878 * 16 pvs linked to from this page. This count may 2879 * be changed upwards or downwards in the future; it 2880 * is only necessary that true be returned for a small 2881 * subset of pmaps for proper page aging. 2882 */ 2883boolean_t 2884pmap_page_exists_quick(pmap, m) 2885 pmap_t pmap; 2886 vm_page_t m; 2887{ 2888 pv_entry_t pv; 2889 int loops = 0; 2890 int s; 2891 2892 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2893 return FALSE; 2894 2895 s = splvm(); 2896 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 2897 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2898 if (pv->pv_pmap == pmap) { 2899 splx(s); 2900 return TRUE; 2901 } 2902 loops++; 2903 if (loops >= 16) 2904 break; 2905 } 2906 splx(s); 2907 return (FALSE); 2908} 2909 2910#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2911/* 2912 * Remove all pages from specified address space 2913 * this aids process exit speeds. Also, this code 2914 * is special cased for current process only, but 2915 * can have the more generic (and slightly slower) 2916 * mode enabled. This is much faster than pmap_remove 2917 * in the case of running down an entire address space. 2918 */ 2919void 2920pmap_remove_pages(pmap, sva, eva) 2921 pmap_t pmap; 2922 vm_offset_t sva, eva; 2923{ 2924 pt_entry_t *pte, tpte; 2925 vm_page_t m; 2926 pv_entry_t pv, npv; 2927 int s; 2928 2929#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2930 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2931 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2932 return; 2933 } 2934#endif 2935 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 2936 s = splvm(); 2937 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2938 2939 if (pv->pv_va >= eva || pv->pv_va < sva) { 2940 npv = TAILQ_NEXT(pv, pv_plist); 2941 continue; 2942 } 2943 2944#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2945 pte = vtopte(pv->pv_va); 2946#else 2947 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2948#endif 2949 tpte = *pte; 2950 2951 if (tpte == 0) { 2952 printf("TPTE at %p IS ZERO @ VA %08x\n", 2953 pte, pv->pv_va); 2954 panic("bad pte"); 2955 } 2956 2957/* 2958 * We cannot remove wired pages from a process' mapping at this time 2959 */ 2960 if (tpte & PG_W) { 2961 npv = TAILQ_NEXT(pv, pv_plist); 2962 continue; 2963 } 2964 2965 m = PHYS_TO_VM_PAGE(tpte); 2966 KASSERT(m->phys_addr == (tpte & PG_FRAME), 2967 ("vm_page_t %p phys_addr mismatch %08x %08x", 2968 m, m->phys_addr, tpte)); 2969 2970 KASSERT(m < &vm_page_array[vm_page_array_size], 2971 ("pmap_remove_pages: bad tpte %x", tpte)); 2972 2973 pv->pv_pmap->pm_stats.resident_count--; 2974 2975 *pte = 0; 2976 2977 /* 2978 * Update the vm_page_t clean and reference bits. 2979 */ 2980 if (tpte & PG_M) { 2981 vm_page_dirty(m); 2982 } 2983 2984 npv = TAILQ_NEXT(pv, pv_plist); 2985 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 2986 2987 m->md.pv_list_count--; 2988 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 2989 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 2990 vm_page_flag_clear(m, PG_WRITEABLE); 2991 } 2992 2993 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 2994 free_pv_entry(pv); 2995 } 2996 splx(s); 2997 pmap_invalidate_all(pmap); 2998} 2999 3000/* 3001 * pmap_is_modified: 3002 * 3003 * Return whether or not the specified physical page was modified 3004 * in any physical maps. 3005 */ 3006boolean_t 3007pmap_is_modified(vm_page_t m) 3008{ 3009 pv_entry_t pv; 3010 pt_entry_t *pte; 3011 int s; 3012 3013 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3014 return FALSE; 3015 3016 s = splvm(); 3017 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 3018 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3019 /* 3020 * if the bit being tested is the modified bit, then 3021 * mark clean_map and ptes as never 3022 * modified. 3023 */ 3024 if (!pmap_track_modified(pv->pv_va)) 3025 continue; 3026#if defined(PMAP_DIAGNOSTIC) 3027 if (!pv->pv_pmap) { 3028 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3029 continue; 3030 } 3031#endif 3032 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3033 if (*pte & PG_M) { 3034 splx(s); 3035 return TRUE; 3036 } 3037 } 3038 splx(s); 3039 return (FALSE); 3040} 3041 3042/* 3043 * this routine is used to modify bits in ptes 3044 */ 3045static __inline void 3046pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3047{ 3048 register pv_entry_t pv; 3049 register pt_entry_t *pte; 3050 int s; 3051 3052 if (!pmap_initialized || (m->flags & PG_FICTITIOUS) || 3053 (!setem && bit == PG_RW && (m->flags & PG_WRITEABLE) == 0)) 3054 return; 3055 3056 s = splvm(); 3057 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 3058 /* 3059 * Loop over all current mappings setting/clearing as appropos If 3060 * setting RO do we need to clear the VAC? 3061 */ 3062 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3063 /* 3064 * don't write protect pager mappings 3065 */ 3066 if (!setem && (bit == PG_RW)) { 3067 if (!pmap_track_modified(pv->pv_va)) 3068 continue; 3069 } 3070 3071#if defined(PMAP_DIAGNOSTIC) 3072 if (!pv->pv_pmap) { 3073 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3074 continue; 3075 } 3076#endif 3077 3078 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3079 3080 if (setem) { 3081 *pte |= bit; 3082 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3083 } else { 3084 pt_entry_t pbits = *pte; 3085 if (pbits & bit) { 3086 if (bit == PG_RW) { 3087 if (pbits & PG_M) { 3088 vm_page_dirty(m); 3089 } 3090 *pte = pbits & ~(PG_M|PG_RW); 3091 } else { 3092 *pte = pbits & ~bit; 3093 } 3094 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3095 } 3096 } 3097 } 3098 if (!setem && bit == PG_RW) 3099 vm_page_flag_clear(m, PG_WRITEABLE); 3100 splx(s); 3101} 3102 3103/* 3104 * pmap_page_protect: 3105 * 3106 * Lower the permission for all mappings to a given page. 3107 */ 3108void 3109pmap_page_protect(vm_page_t m, vm_prot_t prot) 3110{ 3111 if ((prot & VM_PROT_WRITE) == 0) { 3112 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3113 pmap_changebit(m, PG_RW, FALSE); 3114 } else { 3115 pmap_remove_all(m); 3116 } 3117 } 3118} 3119 3120vm_offset_t 3121pmap_phys_address(ppn) 3122 int ppn; 3123{ 3124 return (i386_ptob(ppn)); 3125} 3126 3127/* 3128 * pmap_ts_referenced: 3129 * 3130 * Return a count of reference bits for a page, clearing those bits. 3131 * It is not necessary for every reference bit to be cleared, but it 3132 * is necessary that 0 only be returned when there are truly no 3133 * reference bits set. 3134 * 3135 * XXX: The exact number of bits to check and clear is a matter that 3136 * should be tested and standardized at some point in the future for 3137 * optimal aging of shared pages. 3138 */ 3139int 3140pmap_ts_referenced(vm_page_t m) 3141{ 3142 register pv_entry_t pv, pvf, pvn; 3143 pt_entry_t *pte; 3144 int s; 3145 int rtval = 0; 3146 3147 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3148 return (rtval); 3149 3150 s = splvm(); 3151 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 3152 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3153 3154 pvf = pv; 3155 3156 do { 3157 pvn = TAILQ_NEXT(pv, pv_list); 3158 3159 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3160 3161 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3162 3163 if (!pmap_track_modified(pv->pv_va)) 3164 continue; 3165 3166 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3167 3168 if (pte && (*pte & PG_A)) { 3169 *pte &= ~PG_A; 3170 3171 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3172 3173 rtval++; 3174 if (rtval > 4) { 3175 break; 3176 } 3177 } 3178 } while ((pv = pvn) != NULL && pv != pvf); 3179 } 3180 splx(s); 3181 3182 return (rtval); 3183} 3184 3185/* 3186 * Clear the modify bits on the specified physical page. 3187 */ 3188void 3189pmap_clear_modify(vm_page_t m) 3190{ 3191 pmap_changebit(m, PG_M, FALSE); 3192} 3193 3194/* 3195 * pmap_clear_reference: 3196 * 3197 * Clear the reference bit on the specified physical page. 3198 */ 3199void 3200pmap_clear_reference(vm_page_t m) 3201{ 3202 pmap_changebit(m, PG_A, FALSE); 3203} 3204 3205/* 3206 * Miscellaneous support routines follow 3207 */ 3208 3209static void 3210i386_protection_init() 3211{ 3212 register int *kp, prot; 3213 3214 kp = protection_codes; 3215 for (prot = 0; prot < 8; prot++) { 3216 switch (prot) { 3217 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3218 /* 3219 * Read access is also 0. There isn't any execute bit, 3220 * so just make it readable. 3221 */ 3222 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3223 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3224 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3225 *kp++ = 0; 3226 break; 3227 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3228 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3229 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3230 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3231 *kp++ = PG_RW; 3232 break; 3233 } 3234 } 3235} 3236 3237/* 3238 * Map a set of physical memory pages into the kernel virtual 3239 * address space. Return a pointer to where it is mapped. This 3240 * routine is intended to be used for mapping device memory, 3241 * NOT real memory. 3242 */ 3243void * 3244pmap_mapdev(pa, size) 3245 vm_offset_t pa; 3246 vm_size_t size; 3247{ 3248 vm_offset_t va, tmpva, offset; 3249 3250 offset = pa & PAGE_MASK; 3251 size = roundup(offset + size, PAGE_SIZE); 3252 3253 GIANT_REQUIRED; 3254 3255 va = kmem_alloc_pageable(kernel_map, size); 3256 if (!va) 3257 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3258 3259 pa = pa & PG_FRAME; 3260 for (tmpva = va; size > 0; ) { 3261 pmap_kenter(tmpva, pa); 3262 size -= PAGE_SIZE; 3263 tmpva += PAGE_SIZE; 3264 pa += PAGE_SIZE; 3265 } 3266 pmap_invalidate_range(kernel_pmap, va, tmpva); 3267 return ((void *)(va + offset)); 3268} 3269 3270void 3271pmap_unmapdev(va, size) 3272 vm_offset_t va; 3273 vm_size_t size; 3274{ 3275 vm_offset_t base, offset, tmpva; 3276 pt_entry_t *pte; 3277 3278 base = va & PG_FRAME; 3279 offset = va & PAGE_MASK; 3280 size = roundup(offset + size, PAGE_SIZE); 3281 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE) { 3282 pte = vtopte(tmpva); 3283 *pte = 0; 3284 } 3285 pmap_invalidate_range(kernel_pmap, va, tmpva); 3286 kmem_free(kernel_map, base, size); 3287} 3288 3289/* 3290 * perform the pmap work for mincore 3291 */ 3292int 3293pmap_mincore(pmap, addr) 3294 pmap_t pmap; 3295 vm_offset_t addr; 3296{ 3297 pt_entry_t *ptep, pte; 3298 vm_page_t m; 3299 int val = 0; 3300 3301 ptep = pmap_pte(pmap, addr); 3302 if (ptep == 0) { 3303 return 0; 3304 } 3305 3306 if ((pte = *ptep) != 0) { 3307 vm_offset_t pa; 3308 3309 val = MINCORE_INCORE; 3310 if ((pte & PG_MANAGED) == 0) 3311 return val; 3312 3313 pa = pte & PG_FRAME; 3314 3315 m = PHYS_TO_VM_PAGE(pa); 3316 3317 /* 3318 * Modified by us 3319 */ 3320 if (pte & PG_M) 3321 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3322 else { 3323 /* 3324 * Modified by someone else 3325 */ 3326 vm_page_lock_queues(); 3327 if (m->dirty || pmap_is_modified(m)) 3328 val |= MINCORE_MODIFIED_OTHER; 3329 vm_page_unlock_queues(); 3330 } 3331 /* 3332 * Referenced by us 3333 */ 3334 if (pte & PG_A) 3335 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3336 else { 3337 /* 3338 * Referenced by someone else 3339 */ 3340 vm_page_lock_queues(); 3341 if ((m->flags & PG_REFERENCED) || 3342 pmap_ts_referenced(m)) { 3343 val |= MINCORE_REFERENCED_OTHER; 3344 vm_page_flag_set(m, PG_REFERENCED); 3345 } 3346 vm_page_unlock_queues(); 3347 } 3348 } 3349 return val; 3350} 3351 3352void 3353pmap_activate(struct thread *td) 3354{ 3355 struct proc *p = td->td_proc; 3356 pmap_t pmap; 3357 u_int32_t cr3; 3358 3359 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3360#if defined(SMP) 3361 pmap->pm_active |= PCPU_GET(cpumask); 3362#else 3363 pmap->pm_active |= 1; 3364#endif 3365 cr3 = vtophys(pmap->pm_pdir); 3366 /* XXXKSE this is wrong. 3367 * pmap_activate is for the current thread on the current cpu 3368 */ 3369 if (p->p_flag & P_KSES) { 3370 /* Make sure all other cr3 entries are updated. */ 3371 /* what if they are running? XXXKSE (maybe abort them) */ 3372 FOREACH_THREAD_IN_PROC(p, td) { 3373 td->td_pcb->pcb_cr3 = cr3; 3374 } 3375 } else { 3376 td->td_pcb->pcb_cr3 = cr3; 3377 } 3378 load_cr3(cr3); 3379#ifdef SWTCH_OPTIM_STATS 3380 tlb_flush_count++; 3381#endif 3382} 3383 3384vm_offset_t 3385pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3386{ 3387 3388 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3389 return addr; 3390 } 3391 3392 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3393 return addr; 3394} 3395 3396 3397#if defined(PMAP_DEBUG) 3398pmap_pid_dump(int pid) 3399{ 3400 pmap_t pmap; 3401 struct proc *p; 3402 int npte = 0; 3403 int index; 3404 3405 sx_slock(&allproc_lock); 3406 LIST_FOREACH(p, &allproc, p_list) { 3407 if (p->p_pid != pid) 3408 continue; 3409 3410 if (p->p_vmspace) { 3411 int i,j; 3412 index = 0; 3413 pmap = vmspace_pmap(p->p_vmspace); 3414 for (i = 0; i < NPDEPG; i++) { 3415 pd_entry_t *pde; 3416 pt_entry_t *pte; 3417 vm_offset_t base = i << PDRSHIFT; 3418 3419 pde = &pmap->pm_pdir[i]; 3420 if (pde && pmap_pde_v(pde)) { 3421 for (j = 0; j < NPTEPG; j++) { 3422 vm_offset_t va = base + (j << PAGE_SHIFT); 3423 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3424 if (index) { 3425 index = 0; 3426 printf("\n"); 3427 } 3428 sx_sunlock(&allproc_lock); 3429 return npte; 3430 } 3431 pte = pmap_pte_quick(pmap, va); 3432 if (pte && pmap_pte_v(pte)) { 3433 pt_entry_t pa; 3434 vm_page_t m; 3435 pa = *pte; 3436 m = PHYS_TO_VM_PAGE(pa); 3437 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3438 va, pa, m->hold_count, m->wire_count, m->flags); 3439 npte++; 3440 index++; 3441 if (index >= 2) { 3442 index = 0; 3443 printf("\n"); 3444 } else { 3445 printf(" "); 3446 } 3447 } 3448 } 3449 } 3450 } 3451 } 3452 } 3453 sx_sunlock(&allproc_lock); 3454 return npte; 3455} 3456#endif 3457 3458#if defined(DEBUG) 3459 3460static void pads(pmap_t pm); 3461void pmap_pvdump(vm_offset_t pa); 3462 3463/* print address space of pmap*/ 3464static void 3465pads(pm) 3466 pmap_t pm; 3467{ 3468 int i, j; 3469 vm_offset_t va; 3470 pt_entry_t *ptep; 3471 3472 if (pm == kernel_pmap) 3473 return; 3474 for (i = 0; i < NPDEPG; i++) 3475 if (pm->pm_pdir[i]) 3476 for (j = 0; j < NPTEPG; j++) { 3477 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3478 if (pm == kernel_pmap && va < KERNBASE) 3479 continue; 3480 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3481 continue; 3482 ptep = pmap_pte_quick(pm, va); 3483 if (pmap_pte_v(ptep)) 3484 printf("%x:%x ", va, *ptep); 3485 }; 3486 3487} 3488 3489void 3490pmap_pvdump(pa) 3491 vm_offset_t pa; 3492{ 3493 pv_entry_t pv; 3494 vm_page_t m; 3495 3496 printf("pa %x", pa); 3497 m = PHYS_TO_VM_PAGE(pa); 3498 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3499 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3500 pads(pv->pv_pmap); 3501 } 3502 printf(" "); 3503} 3504#endif 3505