pmap.c revision 110747
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 110747 2003-02-12 04:35:37Z 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 int nkpt; 166vm_offset_t kernel_vm_end; 167extern u_int32_t KERNend; 168 169/* 170 * Data for the pv entry allocation mechanism 171 */ 172static uma_zone_t pvzone; 173static struct vm_object pvzone_obj; 174static int pv_entry_count = 0, pv_entry_max = 0, pv_entry_high_water = 0; 175int pmap_pagedaemon_waken; 176 177/* 178 * All those kernel PT submaps that BSD is so fond of 179 */ 180pt_entry_t *CMAP1 = 0; 181static pt_entry_t *CMAP2, *CMAP3, *ptmmap; 182caddr_t CADDR1 = 0, ptvmmap = 0; 183static caddr_t CADDR2, CADDR3; 184static pt_entry_t *msgbufmap; 185struct msgbuf *msgbufp = 0; 186 187/* 188 * Crashdump maps. 189 */ 190static pt_entry_t *pt_crashdumpmap; 191static caddr_t crashdumpmap; 192 193#ifdef SMP 194extern pt_entry_t *SMPpt; 195#endif 196static pt_entry_t *PMAP1 = 0; 197static pt_entry_t *PADDR1 = 0; 198 199static PMAP_INLINE void free_pv_entry(pv_entry_t pv); 200static pt_entry_t *get_ptbase(pmap_t pmap); 201static pv_entry_t get_pv_entry(void); 202static void i386_protection_init(void); 203static __inline void pmap_changebit(vm_page_t m, int bit, boolean_t setem); 204 205static vm_page_t pmap_enter_quick(pmap_t pmap, vm_offset_t va, 206 vm_page_t m, vm_page_t mpte); 207static int pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t sva); 208static void pmap_remove_page(struct pmap *pmap, vm_offset_t va); 209static int pmap_remove_entry(struct pmap *pmap, vm_page_t m, 210 vm_offset_t va); 211static void pmap_insert_entry(pmap_t pmap, vm_offset_t va, 212 vm_page_t mpte, vm_page_t m); 213 214static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va); 215 216static int pmap_release_free_page(pmap_t pmap, vm_page_t p); 217static vm_page_t _pmap_allocpte(pmap_t pmap, unsigned ptepindex); 218static pt_entry_t *pmap_pte_quick(pmap_t pmap, vm_offset_t va); 219static vm_page_t pmap_page_lookup(vm_object_t object, vm_pindex_t pindex); 220static int pmap_unuse_pt(pmap_t, vm_offset_t, vm_page_t); 221static vm_offset_t pmap_kmem_choose(vm_offset_t addr); 222static void *pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait); 223 224static pd_entry_t pdir4mb; 225 226/* 227 * Routine: pmap_pte 228 * Function: 229 * Extract the page table entry associated 230 * with the given map/virtual_address pair. 231 */ 232 233PMAP_INLINE pt_entry_t * 234pmap_pte(pmap, va) 235 register pmap_t pmap; 236 vm_offset_t va; 237{ 238 pd_entry_t *pdeaddr; 239 240 if (pmap) { 241 pdeaddr = pmap_pde(pmap, va); 242 if (*pdeaddr & PG_PS) 243 return pdeaddr; 244 if (*pdeaddr) { 245 return get_ptbase(pmap) + i386_btop(va); 246 } 247 } 248 return (0); 249} 250 251/* 252 * Move the kernel virtual free pointer to the next 253 * 4MB. This is used to help improve performance 254 * by using a large (4MB) page for much of the kernel 255 * (.text, .data, .bss) 256 */ 257static vm_offset_t 258pmap_kmem_choose(vm_offset_t addr) 259{ 260 vm_offset_t newaddr = addr; 261 262#ifndef DISABLE_PSE 263 if (cpu_feature & CPUID_PSE) 264 newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 265#endif 266 return newaddr; 267} 268 269/* 270 * Bootstrap the system enough to run with virtual memory. 271 * 272 * On the i386 this is called after mapping has already been enabled 273 * and just syncs the pmap module with what has already been done. 274 * [We can't call it easily with mapping off since the kernel is not 275 * mapped with PA == VA, hence we would have to relocate every address 276 * from the linked base (virtual) address "KERNBASE" to the actual 277 * (physical) address starting relative to 0] 278 */ 279void 280pmap_bootstrap(firstaddr, loadaddr) 281 vm_offset_t firstaddr; 282 vm_offset_t loadaddr; 283{ 284 vm_offset_t va; 285 pt_entry_t *pte; 286 int i; 287 288 avail_start = firstaddr; 289 290 /* 291 * XXX The calculation of virtual_avail is wrong. It's NKPT*PAGE_SIZE too 292 * large. It should instead be correctly calculated in locore.s and 293 * not based on 'first' (which is a physical address, not a virtual 294 * address, for the start of unused physical memory). The kernel 295 * page tables are NOT double mapped and thus should not be included 296 * in this calculation. 297 */ 298 virtual_avail = (vm_offset_t) KERNBASE + firstaddr; 299 virtual_avail = pmap_kmem_choose(virtual_avail); 300 301 virtual_end = VM_MAX_KERNEL_ADDRESS; 302 303 /* 304 * Initialize protection array. 305 */ 306 i386_protection_init(); 307 308 /* 309 * Initialize the kernel pmap (which is statically allocated). 310 */ 311 kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD); 312 kernel_pmap->pm_active = -1; /* don't allow deactivation */ 313 TAILQ_INIT(&kernel_pmap->pm_pvlist); 314 LIST_INIT(&allpmaps); 315 mtx_init(&allpmaps_lock, "allpmaps", NULL, MTX_SPIN); 316 mtx_lock_spin(&allpmaps_lock); 317 LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list); 318 mtx_unlock_spin(&allpmaps_lock); 319 nkpt = NKPT; 320 321 /* 322 * Reserve some special page table entries/VA space for temporary 323 * mapping of pages. 324 */ 325#define SYSMAP(c, p, v, n) \ 326 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n); 327 328 va = virtual_avail; 329 pte = (pt_entry_t *) pmap_pte(kernel_pmap, va); 330 331 /* 332 * CMAP1/CMAP2 are used for zeroing and copying pages. 333 * CMAP3 is used for the idle process page zeroing. 334 */ 335 SYSMAP(caddr_t, CMAP1, CADDR1, 1) 336 SYSMAP(caddr_t, CMAP2, CADDR2, 1) 337 SYSMAP(caddr_t, CMAP3, CADDR3, 1) 338 339 /* 340 * Crashdump maps. 341 */ 342 SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS); 343 344 /* 345 * ptvmmap is used for reading arbitrary physical pages via /dev/mem. 346 * XXX ptmmap is not used. 347 */ 348 SYSMAP(caddr_t, ptmmap, ptvmmap, 1) 349 350 /* 351 * msgbufp is used to map the system message buffer. 352 * XXX msgbufmap is not used. 353 */ 354 SYSMAP(struct msgbuf *, msgbufmap, msgbufp, 355 atop(round_page(MSGBUF_SIZE))) 356 357 /* 358 * ptemap is used for pmap_pte_quick 359 */ 360 SYSMAP(pt_entry_t *, PMAP1, PADDR1, 1); 361 362 virtual_avail = va; 363 364 *CMAP1 = *CMAP2 = 0; 365 for (i = 0; i < NKPT; i++) 366 PTD[i] = 0; 367 368 pgeflag = 0; 369#ifndef DISABLE_PG_G 370 if (cpu_feature & CPUID_PGE) 371 pgeflag = PG_G; 372#endif 373 374/* 375 * Initialize the 4MB page size flag 376 */ 377 pseflag = 0; 378/* 379 * The 4MB page version of the initial 380 * kernel page mapping. 381 */ 382 pdir4mb = 0; 383 384#ifndef DISABLE_PSE 385 if (cpu_feature & CPUID_PSE) { 386 pd_entry_t ptditmp; 387 /* 388 * Note that we have enabled PSE mode 389 */ 390 pseflag = PG_PS; 391 ptditmp = *(PTmap + i386_btop(KERNBASE)); 392 ptditmp &= ~(NBPDR - 1); 393 ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag; 394 pdir4mb = ptditmp; 395 } 396#endif 397#ifndef SMP 398 /* 399 * Turn on PGE/PSE. SMP does this later on since the 400 * 4K page tables are required for AP boot (for now). 401 * XXX fixme. 402 */ 403 pmap_set_opt(); 404#endif 405#ifdef SMP 406 if (cpu_apic_address == 0) 407 panic("pmap_bootstrap: no local apic! (non-SMP hardware?)"); 408 409 /* local apic is mapped on last page */ 410 SMPpt[NPTEPG - 1] = (pt_entry_t)(PG_V | PG_RW | PG_N | pgeflag | 411 (cpu_apic_address & PG_FRAME)); 412#endif 413 invltlb(); 414} 415 416/* 417 * Enable 4MB page mode for MP startup. Turn on PG_G support. 418 * BSP will run this after all the AP's have started up. 419 */ 420void 421pmap_set_opt(void) 422{ 423 pt_entry_t *pte; 424 vm_offset_t va, endva; 425 426 if (pgeflag && (cpu_feature & CPUID_PGE)) { 427 load_cr4(rcr4() | CR4_PGE); 428 invltlb(); /* Insurance */ 429 } 430#ifndef DISABLE_PSE 431 if (pseflag && (cpu_feature & CPUID_PSE)) { 432 load_cr4(rcr4() | CR4_PSE); 433 invltlb(); /* Insurance */ 434 } 435#endif 436 if (PCPU_GET(cpuid) == 0) { 437#ifndef DISABLE_PSE 438 if (pdir4mb) { 439 kernel_pmap->pm_pdir[KPTDI] = PTD[KPTDI] = pdir4mb; 440 invltlb(); /* Insurance */ 441 } 442#endif 443 if (pgeflag) { 444 /* Turn on PG_G for text, data, bss pages. */ 445 va = (vm_offset_t)btext; 446#ifndef DISABLE_PSE 447 if (pseflag && (cpu_feature & CPUID_PSE)) { 448 if (va < KERNBASE + (1 << PDRSHIFT)) 449 va = KERNBASE + (1 << PDRSHIFT); 450 } 451#endif 452 endva = KERNBASE + KERNend; 453 while (va < endva) { 454 pte = vtopte(va); 455 if (*pte) 456 *pte |= pgeflag; 457 va += PAGE_SIZE; 458 } 459 invltlb(); /* Insurance */ 460 } 461 /* 462 * We do not need to broadcast the invltlb here, because 463 * each AP does it the moment it is released from the boot 464 * lock. See ap_init(). 465 */ 466 } 467} 468 469static void * 470pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait) 471{ 472 *flags = UMA_SLAB_PRIV; 473 return (void *)kmem_alloc(kernel_map, bytes); 474} 475 476/* 477 * Initialize the pmap module. 478 * Called by vm_init, to initialize any structures that the pmap 479 * system needs to map virtual memory. 480 * pmap_init has been enhanced to support in a fairly consistant 481 * way, discontiguous physical memory. 482 */ 483void 484pmap_init(phys_start, phys_end) 485 vm_offset_t phys_start, phys_end; 486{ 487 int i; 488 int initial_pvs; 489 490 /* 491 * Allocate memory for random pmap data structures. Includes the 492 * pv_head_table. 493 */ 494 495 for(i = 0; i < vm_page_array_size; i++) { 496 vm_page_t m; 497 498 m = &vm_page_array[i]; 499 TAILQ_INIT(&m->md.pv_list); 500 m->md.pv_list_count = 0; 501 } 502 503 /* 504 * init the pv free list 505 */ 506 initial_pvs = vm_page_array_size; 507 if (initial_pvs < MINPV) 508 initial_pvs = MINPV; 509 pvzone = uma_zcreate("PV ENTRY", sizeof (struct pv_entry), NULL, NULL, 510 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM); 511 uma_zone_set_allocf(pvzone, pmap_allocf); 512 uma_prealloc(pvzone, initial_pvs); 513 514 /* 515 * Now it is safe to enable pv_table recording. 516 */ 517 pmap_initialized = TRUE; 518} 519 520/* 521 * Initialize the address space (zone) for the pv_entries. Set a 522 * high water mark so that the system can recover from excessive 523 * numbers of pv entries. 524 */ 525void 526pmap_init2() 527{ 528 int shpgperproc = PMAP_SHPGPERPROC; 529 530 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc); 531 pv_entry_max = shpgperproc * maxproc + vm_page_array_size; 532 TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max); 533 pv_entry_high_water = 9 * (pv_entry_max / 10); 534 uma_zone_set_obj(pvzone, &pvzone_obj, pv_entry_max); 535} 536 537 538/*************************************************** 539 * Low level helper routines..... 540 ***************************************************/ 541 542#if defined(PMAP_DIAGNOSTIC) 543 544/* 545 * This code checks for non-writeable/modified pages. 546 * This should be an invalid condition. 547 */ 548static int 549pmap_nw_modified(pt_entry_t ptea) 550{ 551 int pte; 552 553 pte = (int) ptea; 554 555 if ((pte & (PG_M|PG_RW)) == PG_M) 556 return 1; 557 else 558 return 0; 559} 560#endif 561 562 563/* 564 * this routine defines the region(s) of memory that should 565 * not be tested for the modified bit. 566 */ 567static PMAP_INLINE int 568pmap_track_modified(vm_offset_t va) 569{ 570 if ((va < kmi.clean_sva) || (va >= kmi.clean_eva)) 571 return 1; 572 else 573 return 0; 574} 575 576#ifdef I386_CPU 577/* 578 * i386 only has "invalidate everything" and no SMP to worry about. 579 */ 580PMAP_INLINE void 581pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 582{ 583 584 if (pmap == kernel_pmap || pmap->pm_active) 585 invltlb(); 586} 587 588PMAP_INLINE void 589pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 590{ 591 592 if (pmap == kernel_pmap || pmap->pm_active) 593 invltlb(); 594} 595 596PMAP_INLINE void 597pmap_invalidate_all(pmap_t pmap) 598{ 599 600 if (pmap == kernel_pmap || pmap->pm_active) 601 invltlb(); 602} 603#else /* !I386_CPU */ 604#ifdef SMP 605/* 606 * For SMP, these functions have to use the IPI mechanism for coherence. 607 */ 608void 609pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 610{ 611 u_int cpumask; 612 u_int other_cpus; 613 614 critical_enter(); 615 /* 616 * We need to disable interrupt preemption but MUST NOT have 617 * interrupts disabled here. 618 * XXX we may need to hold schedlock to get a coherent pm_active 619 */ 620 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 621 invlpg(va); 622 smp_invlpg(va); 623 } else { 624 cpumask = PCPU_GET(cpumask); 625 other_cpus = PCPU_GET(other_cpus); 626 if (pmap->pm_active & cpumask) 627 invlpg(va); 628 if (pmap->pm_active & other_cpus) 629 smp_masked_invlpg(pmap->pm_active & other_cpus, va); 630 } 631 critical_exit(); 632} 633 634void 635pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 636{ 637 u_int cpumask; 638 u_int other_cpus; 639 vm_offset_t addr; 640 641 critical_enter(); 642 /* 643 * We need to disable interrupt preemption but MUST NOT have 644 * interrupts disabled here. 645 * XXX we may need to hold schedlock to get a coherent pm_active 646 */ 647 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 648 for (addr = sva; addr < eva; addr += PAGE_SIZE) 649 invlpg(addr); 650 smp_invlpg_range(sva, eva); 651 } else { 652 cpumask = PCPU_GET(cpumask); 653 other_cpus = PCPU_GET(other_cpus); 654 if (pmap->pm_active & cpumask) 655 for (addr = sva; addr < eva; addr += PAGE_SIZE) 656 invlpg(addr); 657 if (pmap->pm_active & other_cpus) 658 smp_masked_invlpg_range(pmap->pm_active & other_cpus, 659 sva, eva); 660 } 661 critical_exit(); 662} 663 664void 665pmap_invalidate_all(pmap_t pmap) 666{ 667 u_int cpumask; 668 u_int other_cpus; 669 670#ifdef SWTCH_OPTIM_STATS 671 tlb_flush_count++; 672#endif 673 critical_enter(); 674 /* 675 * We need to disable interrupt preemption but MUST NOT have 676 * interrupts disabled here. 677 * XXX we may need to hold schedlock to get a coherent pm_active 678 */ 679 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 680 invltlb(); 681 smp_invltlb(); 682 } else { 683 cpumask = PCPU_GET(cpumask); 684 other_cpus = PCPU_GET(other_cpus); 685 if (pmap->pm_active & cpumask) 686 invltlb(); 687 if (pmap->pm_active & other_cpus) 688 smp_masked_invltlb(pmap->pm_active & other_cpus); 689 } 690 critical_exit(); 691} 692#else /* !SMP */ 693/* 694 * Normal, non-SMP, 486+ invalidation functions. 695 * We inline these within pmap.c for speed. 696 */ 697PMAP_INLINE void 698pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 699{ 700 701 if (pmap == kernel_pmap || pmap->pm_active) 702 invlpg(va); 703} 704 705PMAP_INLINE void 706pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 707{ 708 vm_offset_t addr; 709 710 if (pmap == kernel_pmap || pmap->pm_active) 711 for (addr = sva; addr < eva; addr += PAGE_SIZE) 712 invlpg(addr); 713} 714 715PMAP_INLINE void 716pmap_invalidate_all(pmap_t pmap) 717{ 718 719 if (pmap == kernel_pmap || pmap->pm_active) 720 invltlb(); 721} 722#endif /* !SMP */ 723#endif /* !I386_CPU */ 724 725/* 726 * Return an address which is the base of the Virtual mapping of 727 * all the PTEs for the given pmap. Note this doesn't say that 728 * all the PTEs will be present or that the pages there are valid. 729 * The PTEs are made available by the recursive mapping trick. 730 * It will map in the alternate PTE space if needed. 731 */ 732static pt_entry_t * 733get_ptbase(pmap) 734 pmap_t pmap; 735{ 736 pd_entry_t frame; 737 738 /* are we current address space or kernel? */ 739 if (pmap == kernel_pmap) 740 return PTmap; 741 frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 742 if (frame == (PTDpde & PG_FRAME)) 743 return PTmap; 744 /* otherwise, we are alternate address space */ 745 if (frame != (APTDpde & PG_FRAME)) { 746 APTDpde = (pd_entry_t) (frame | PG_RW | PG_V); 747 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 748 } 749 return APTmap; 750} 751 752/* 753 * Super fast pmap_pte routine best used when scanning 754 * the pv lists. This eliminates many coarse-grained 755 * invltlb calls. Note that many of the pv list 756 * scans are across different pmaps. It is very wasteful 757 * to do an entire invltlb for checking a single mapping. 758 */ 759 760static pt_entry_t * 761pmap_pte_quick(pmap, va) 762 register pmap_t pmap; 763 vm_offset_t va; 764{ 765 pd_entry_t pde, newpf; 766 pde = pmap->pm_pdir[va >> PDRSHIFT]; 767 if (pde != 0) { 768 pd_entry_t frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 769 unsigned index = i386_btop(va); 770 /* are we current address space or kernel? */ 771 if (pmap == kernel_pmap || frame == (PTDpde & PG_FRAME)) 772 return PTmap + index; 773 newpf = pde & PG_FRAME; 774 if (((*PMAP1) & PG_FRAME) != newpf) { 775 *PMAP1 = newpf | PG_RW | PG_V; 776 pmap_invalidate_page(kernel_pmap, (vm_offset_t)PADDR1); 777 } 778 return PADDR1 + (index & (NPTEPG - 1)); 779 } 780 return (0); 781} 782 783/* 784 * Routine: pmap_extract 785 * Function: 786 * Extract the physical page address associated 787 * with the given map/virtual_address pair. 788 */ 789vm_offset_t 790pmap_extract(pmap, va) 791 register pmap_t pmap; 792 vm_offset_t va; 793{ 794 vm_offset_t rtval; /* XXX FIXME */ 795 vm_offset_t pdirindex; 796 797 if (pmap == 0) 798 return 0; 799 pdirindex = va >> PDRSHIFT; 800 rtval = pmap->pm_pdir[pdirindex]; 801 if (rtval != 0) { 802 pt_entry_t *pte; 803 if ((rtval & PG_PS) != 0) { 804 rtval &= ~(NBPDR - 1); 805 rtval |= va & (NBPDR - 1); 806 return rtval; 807 } 808 pte = get_ptbase(pmap) + i386_btop(va); 809 rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); 810 return rtval; 811 } 812 return 0; 813 814} 815 816/*************************************************** 817 * Low level mapping routines..... 818 ***************************************************/ 819 820/* 821 * Add a wired page to the kva. 822 * Note: not SMP coherent. 823 */ 824PMAP_INLINE void 825pmap_kenter(vm_offset_t va, vm_offset_t pa) 826{ 827 pt_entry_t *pte; 828 829 pte = vtopte(va); 830 *pte = pa | PG_RW | PG_V | pgeflag; 831} 832 833/* 834 * Remove a page from the kernel pagetables. 835 * Note: not SMP coherent. 836 */ 837PMAP_INLINE void 838pmap_kremove(vm_offset_t va) 839{ 840 pt_entry_t *pte; 841 842 pte = vtopte(va); 843 *pte = 0; 844} 845 846/* 847 * Used to map a range of physical addresses into kernel 848 * virtual address space. 849 * 850 * The value passed in '*virt' is a suggested virtual address for 851 * the mapping. Architectures which can support a direct-mapped 852 * physical to virtual region can return the appropriate address 853 * within that region, leaving '*virt' unchanged. Other 854 * architectures should map the pages starting at '*virt' and 855 * update '*virt' with the first usable address after the mapped 856 * region. 857 */ 858vm_offset_t 859pmap_map(vm_offset_t *virt, vm_offset_t start, vm_offset_t end, int prot) 860{ 861 vm_offset_t va, sva; 862 863 va = sva = *virt; 864 while (start < end) { 865 pmap_kenter(va, start); 866 va += PAGE_SIZE; 867 start += PAGE_SIZE; 868 } 869 pmap_invalidate_range(kernel_pmap, sva, va); 870 *virt = va; 871 return (sva); 872} 873 874 875/* 876 * Add a list of wired pages to the kva 877 * this routine is only used for temporary 878 * kernel mappings that do not need to have 879 * page modification or references recorded. 880 * Note that old mappings are simply written 881 * over. The page *must* be wired. 882 * Note: SMP coherent. Uses a ranged shootdown IPI. 883 */ 884void 885pmap_qenter(vm_offset_t sva, vm_page_t *m, int count) 886{ 887 vm_offset_t va; 888 889 va = sva; 890 while (count-- > 0) { 891 pmap_kenter(va, VM_PAGE_TO_PHYS(*m)); 892 va += PAGE_SIZE; 893 m++; 894 } 895 pmap_invalidate_range(kernel_pmap, sva, va); 896} 897 898/* 899 * This routine tears out page mappings from the 900 * kernel -- it is meant only for temporary mappings. 901 * Note: SMP coherent. Uses a ranged shootdown IPI. 902 */ 903void 904pmap_qremove(vm_offset_t sva, int count) 905{ 906 vm_offset_t va; 907 908 va = sva; 909 while (count-- > 0) { 910 pmap_kremove(va); 911 va += PAGE_SIZE; 912 } 913 pmap_invalidate_range(kernel_pmap, sva, va); 914} 915 916static vm_page_t 917pmap_page_lookup(vm_object_t object, vm_pindex_t pindex) 918{ 919 vm_page_t m; 920 921retry: 922 m = vm_page_lookup(object, pindex); 923 if (m != NULL) { 924 vm_page_lock_queues(); 925 if (vm_page_sleep_if_busy(m, FALSE, "pplookp")) 926 goto retry; 927 vm_page_unlock_queues(); 928 } 929 return m; 930} 931 932#ifndef KSTACK_MAX_PAGES 933#define KSTACK_MAX_PAGES 32 934#endif 935 936/* 937 * Create the kernel stack (including pcb for i386) for a new thread. 938 * This routine directly affects the fork perf for a process and 939 * create performance for a thread. 940 */ 941void 942pmap_new_thread(struct thread *td, int pages) 943{ 944 int i; 945 vm_page_t ma[KSTACK_MAX_PAGES]; 946 vm_object_t ksobj; 947 vm_page_t m; 948 vm_offset_t ks; 949 950 /* Bounds check */ 951 if (pages <= 1) 952 pages = KSTACK_PAGES; 953 else if (pages > KSTACK_MAX_PAGES) 954 pages = KSTACK_MAX_PAGES; 955 956 /* 957 * allocate object for the kstack 958 */ 959 ksobj = vm_object_allocate(OBJT_DEFAULT, pages); 960 td->td_kstack_obj = ksobj; 961 962 /* get a kernel virtual address for the kstack for this thread */ 963#ifdef KSTACK_GUARD 964 ks = kmem_alloc_nofault(kernel_map, (pages + 1) * PAGE_SIZE); 965 if (ks == 0) 966 panic("pmap_new_thread: kstack allocation failed"); 967 if (*vtopte(ks) != 0) 968 pmap_qremove(ks, 1); 969 ks += PAGE_SIZE; 970 td->td_kstack = ks; 971#else 972 /* get a kernel virtual address for the kstack for this thread */ 973 ks = kmem_alloc_nofault(kernel_map, pages * PAGE_SIZE); 974 if (ks == 0) 975 panic("pmap_new_thread: kstack allocation failed"); 976 td->td_kstack = ks; 977#endif 978 /* 979 * Knowing the number of pages allocated is useful when you 980 * want to deallocate them. 981 */ 982 td->td_kstack_pages = pages; 983 984 /* 985 * For the length of the stack, link in a real page of ram for each 986 * page of stack. 987 */ 988 for (i = 0; i < pages; i++) { 989 /* 990 * Get a kernel stack page 991 */ 992 m = vm_page_grab(ksobj, i, 993 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED); 994 ma[i] = m; 995 996 vm_page_lock_queues(); 997 vm_page_wakeup(m); 998 vm_page_flag_clear(m, PG_ZERO); 999 m->valid = VM_PAGE_BITS_ALL; 1000 vm_page_unlock_queues(); 1001 } 1002 pmap_qenter(ks, ma, pages); 1003} 1004 1005/* 1006 * Dispose the kernel stack for a thread that has exited. 1007 * This routine directly impacts the exit perf of a process and thread. 1008 */ 1009void 1010pmap_dispose_thread(td) 1011 struct thread *td; 1012{ 1013 int i; 1014 int pages; 1015 vm_object_t ksobj; 1016 vm_offset_t ks; 1017 vm_page_t m; 1018 1019 pages = td->td_kstack_pages; 1020 ksobj = td->td_kstack_obj; 1021 ks = td->td_kstack; 1022 pmap_qremove(ks, pages); 1023 for (i = 0; i < pages; i++) { 1024 m = vm_page_lookup(ksobj, i); 1025 if (m == NULL) 1026 panic("pmap_dispose_thread: kstack already missing?"); 1027 vm_page_lock_queues(); 1028 vm_page_busy(m); 1029 vm_page_unwire(m, 0); 1030 vm_page_free(m); 1031 vm_page_unlock_queues(); 1032 } 1033 /* 1034 * Free the space that this stack was mapped to in the kernel 1035 * address map. 1036 */ 1037#ifdef KSTACK_GUARD 1038 kmem_free(kernel_map, ks - PAGE_SIZE, (pages + 1) * PAGE_SIZE); 1039#else 1040 kmem_free(kernel_map, ks, pages * PAGE_SIZE); 1041#endif 1042 vm_object_deallocate(ksobj); 1043} 1044 1045/* 1046 * Set up a variable sized alternate kstack. Though it may look MI, it may 1047 * need to be different on certain arches like ia64. 1048 */ 1049void 1050pmap_new_altkstack(struct thread *td, int pages) 1051{ 1052 /* shuffle the original stack */ 1053 td->td_altkstack_obj = td->td_kstack_obj; 1054 td->td_altkstack = td->td_kstack; 1055 td->td_altkstack_pages = td->td_kstack_pages; 1056 1057 pmap_new_thread(td, pages); 1058} 1059 1060void 1061pmap_dispose_altkstack(td) 1062 struct thread *td; 1063{ 1064 pmap_dispose_thread(td); 1065 1066 /* restore the original kstack */ 1067 td->td_kstack = td->td_altkstack; 1068 td->td_kstack_obj = td->td_altkstack_obj; 1069 td->td_kstack_pages = td->td_altkstack_pages; 1070 td->td_altkstack = 0; 1071 td->td_altkstack_obj = NULL; 1072 td->td_altkstack_pages = 0; 1073} 1074 1075/* 1076 * Allow the Kernel stack for a thread to be prejudicially paged out. 1077 */ 1078void 1079pmap_swapout_thread(td) 1080 struct thread *td; 1081{ 1082 int i; 1083 int pages; 1084 vm_object_t ksobj; 1085 vm_offset_t ks; 1086 vm_page_t m; 1087 1088 pages = td->td_kstack_pages; 1089 ksobj = td->td_kstack_obj; 1090 ks = td->td_kstack; 1091 pmap_qremove(ks, pages); 1092 for (i = 0; i < pages; i++) { 1093 m = vm_page_lookup(ksobj, i); 1094 if (m == NULL) 1095 panic("pmap_swapout_thread: kstack already missing?"); 1096 vm_page_lock_queues(); 1097 vm_page_dirty(m); 1098 vm_page_unwire(m, 0); 1099 vm_page_unlock_queues(); 1100 } 1101} 1102 1103/* 1104 * Bring the kernel stack for a specified thread back in. 1105 */ 1106void 1107pmap_swapin_thread(td) 1108 struct thread *td; 1109{ 1110 int i, rv; 1111 int pages; 1112 vm_page_t ma[KSTACK_MAX_PAGES]; 1113 vm_object_t ksobj; 1114 vm_offset_t ks; 1115 vm_page_t m; 1116 1117 pages = td->td_kstack_pages; 1118 ksobj = td->td_kstack_obj; 1119 ks = td->td_kstack; 1120 for (i = 0; i < pages; i++) { 1121 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1122 if (m->valid != VM_PAGE_BITS_ALL) { 1123 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1124 if (rv != VM_PAGER_OK) 1125 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1126 m = vm_page_lookup(ksobj, i); 1127 m->valid = VM_PAGE_BITS_ALL; 1128 } 1129 ma[i] = m; 1130 vm_page_lock_queues(); 1131 vm_page_wire(m); 1132 vm_page_wakeup(m); 1133 vm_page_unlock_queues(); 1134 } 1135 pmap_qenter(ks, ma, pages); 1136} 1137 1138/*************************************************** 1139 * Page table page management routines..... 1140 ***************************************************/ 1141 1142/* 1143 * This routine unholds page table pages, and if the hold count 1144 * drops to zero, then it decrements the wire count. 1145 */ 1146static int 1147_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1148{ 1149 1150 while (vm_page_sleep_if_busy(m, FALSE, "pmuwpt")) 1151 vm_page_lock_queues(); 1152 1153 if (m->hold_count == 0) { 1154 vm_offset_t pteva; 1155 /* 1156 * unmap the page table page 1157 */ 1158 pmap->pm_pdir[m->pindex] = 0; 1159 --pmap->pm_stats.resident_count; 1160 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1161 (PTDpde & PG_FRAME)) { 1162 /* 1163 * Do an invltlb to make the invalidated mapping 1164 * take effect immediately. 1165 */ 1166 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); 1167 pmap_invalidate_page(pmap, pteva); 1168 } 1169 1170 if (pmap->pm_ptphint == m) 1171 pmap->pm_ptphint = NULL; 1172 1173 /* 1174 * If the page is finally unwired, simply free it. 1175 */ 1176 --m->wire_count; 1177 if (m->wire_count == 0) { 1178 vm_page_busy(m); 1179 vm_page_free_zero(m); 1180 atomic_subtract_int(&cnt.v_wire_count, 1); 1181 } 1182 return 1; 1183 } 1184 return 0; 1185} 1186 1187static PMAP_INLINE int 1188pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1189{ 1190 vm_page_unhold(m); 1191 if (m->hold_count == 0) 1192 return _pmap_unwire_pte_hold(pmap, m); 1193 else 1194 return 0; 1195} 1196 1197/* 1198 * After removing a page table entry, this routine is used to 1199 * conditionally free the page, and manage the hold/wire counts. 1200 */ 1201static int 1202pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1203{ 1204 unsigned ptepindex; 1205 if (va >= VM_MAXUSER_ADDRESS) 1206 return 0; 1207 1208 if (mpte == NULL) { 1209 ptepindex = (va >> PDRSHIFT); 1210 if (pmap->pm_ptphint && 1211 (pmap->pm_ptphint->pindex == ptepindex)) { 1212 mpte = pmap->pm_ptphint; 1213 } else { 1214 while ((mpte = vm_page_lookup(pmap->pm_pteobj, ptepindex)) != NULL && 1215 vm_page_sleep_if_busy(mpte, FALSE, "pulook")) 1216 vm_page_lock_queues(); 1217 pmap->pm_ptphint = mpte; 1218 } 1219 } 1220 1221 return pmap_unwire_pte_hold(pmap, mpte); 1222} 1223 1224void 1225pmap_pinit0(pmap) 1226 struct pmap *pmap; 1227{ 1228 pmap->pm_pdir = 1229 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1230 pmap_kenter((vm_offset_t)pmap->pm_pdir, (vm_offset_t)IdlePTD); 1231#ifndef I386_CPU 1232 invlpg((vm_offset_t)pmap->pm_pdir); 1233#else 1234 invltlb(); 1235#endif 1236 pmap->pm_ptphint = NULL; 1237 pmap->pm_active = 0; 1238 TAILQ_INIT(&pmap->pm_pvlist); 1239 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1240 mtx_lock_spin(&allpmaps_lock); 1241 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1242 mtx_unlock_spin(&allpmaps_lock); 1243} 1244 1245/* 1246 * Initialize a preallocated and zeroed pmap structure, 1247 * such as one in a vmspace structure. 1248 */ 1249void 1250pmap_pinit(pmap) 1251 register struct pmap *pmap; 1252{ 1253 vm_page_t ptdpg; 1254 1255 /* 1256 * No need to allocate page table space yet but we do need a valid 1257 * page directory table. 1258 */ 1259 if (pmap->pm_pdir == NULL) 1260 pmap->pm_pdir = 1261 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1262 1263 /* 1264 * allocate object for the ptes 1265 */ 1266 if (pmap->pm_pteobj == NULL) 1267 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1268 1269 /* 1270 * allocate the page directory page 1271 */ 1272 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1273 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED | VM_ALLOC_ZERO); 1274 vm_page_lock_queues(); 1275 vm_page_flag_clear(ptdpg, PG_BUSY); 1276 ptdpg->valid = VM_PAGE_BITS_ALL; 1277 vm_page_unlock_queues(); 1278 1279 pmap_qenter((vm_offset_t) pmap->pm_pdir, &ptdpg, 1); 1280 if ((ptdpg->flags & PG_ZERO) == 0) 1281 bzero(pmap->pm_pdir, PAGE_SIZE); 1282 1283 mtx_lock_spin(&allpmaps_lock); 1284 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1285 mtx_unlock_spin(&allpmaps_lock); 1286 /* Wire in kernel global address entries. */ 1287 /* XXX copies current process, does not fill in MPPTDI */ 1288 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1289#ifdef SMP 1290 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1291#endif 1292 1293 /* install self-referential address mapping entry */ 1294 pmap->pm_pdir[PTDPTDI] = 1295 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1296 1297 pmap->pm_active = 0; 1298 pmap->pm_ptphint = NULL; 1299 TAILQ_INIT(&pmap->pm_pvlist); 1300 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1301} 1302 1303/* 1304 * Wire in kernel global address entries. To avoid a race condition 1305 * between pmap initialization and pmap_growkernel, this procedure 1306 * should be called after the vmspace is attached to the process 1307 * but before this pmap is activated. 1308 */ 1309void 1310pmap_pinit2(pmap) 1311 struct pmap *pmap; 1312{ 1313 /* XXX: Remove this stub when no longer called */ 1314} 1315 1316static int 1317pmap_release_free_page(pmap_t pmap, vm_page_t p) 1318{ 1319 pd_entry_t *pde = pmap->pm_pdir; 1320 1321 /* 1322 * This code optimizes the case of freeing non-busy 1323 * page-table pages. Those pages are zero now, and 1324 * might as well be placed directly into the zero queue. 1325 */ 1326 vm_page_lock_queues(); 1327 if (vm_page_sleep_if_busy(p, FALSE, "pmaprl")) 1328 return (0); 1329 vm_page_busy(p); 1330 1331 /* 1332 * Remove the page table page from the processes address space. 1333 */ 1334 pde[p->pindex] = 0; 1335 pmap->pm_stats.resident_count--; 1336 1337 if (p->hold_count) { 1338 panic("pmap_release: freeing held page table page"); 1339 } 1340 /* 1341 * Page directory pages need to have the kernel 1342 * stuff cleared, so they can go into the zero queue also. 1343 */ 1344 if (p->pindex == PTDPTDI) { 1345 bzero(pde + KPTDI, nkpt * PTESIZE); 1346#ifdef SMP 1347 pde[MPPTDI] = 0; 1348#endif 1349 pde[APTDPTDI] = 0; 1350 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1351 } 1352 1353 if (pmap->pm_ptphint == p) 1354 pmap->pm_ptphint = NULL; 1355 1356 p->wire_count--; 1357 atomic_subtract_int(&cnt.v_wire_count, 1); 1358 vm_page_free_zero(p); 1359 vm_page_unlock_queues(); 1360 return 1; 1361} 1362 1363/* 1364 * this routine is called if the page table page is not 1365 * mapped correctly. 1366 */ 1367static vm_page_t 1368_pmap_allocpte(pmap, ptepindex) 1369 pmap_t pmap; 1370 unsigned ptepindex; 1371{ 1372 vm_offset_t pteva, ptepa; /* XXXPA */ 1373 vm_page_t m; 1374 1375 /* 1376 * Find or fabricate a new pagetable page 1377 */ 1378 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1379 VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1380 1381 KASSERT(m->queue == PQ_NONE, 1382 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1383 1384 /* 1385 * Increment the hold count for the page table page 1386 * (denoting a new mapping.) 1387 */ 1388 m->hold_count++; 1389 1390 /* 1391 * Map the pagetable page into the process address space, if 1392 * it isn't already there. 1393 */ 1394 1395 pmap->pm_stats.resident_count++; 1396 1397 ptepa = VM_PAGE_TO_PHYS(m); 1398 pmap->pm_pdir[ptepindex] = 1399 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1400 1401 /* 1402 * Set the page table hint 1403 */ 1404 pmap->pm_ptphint = m; 1405 1406 /* 1407 * Try to use the new mapping, but if we cannot, then 1408 * do it with the routine that maps the page explicitly. 1409 */ 1410 if ((m->flags & PG_ZERO) == 0) { 1411 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1412 (PTDpde & PG_FRAME)) { 1413 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1414 bzero((caddr_t) pteva, PAGE_SIZE); 1415 } else { 1416 pmap_zero_page(m); 1417 } 1418 } 1419 vm_page_lock_queues(); 1420 m->valid = VM_PAGE_BITS_ALL; 1421 vm_page_flag_clear(m, PG_ZERO); 1422 vm_page_wakeup(m); 1423 vm_page_unlock_queues(); 1424 1425 return m; 1426} 1427 1428static vm_page_t 1429pmap_allocpte(pmap_t pmap, vm_offset_t va) 1430{ 1431 unsigned ptepindex; 1432 pd_entry_t ptepa; 1433 vm_page_t m; 1434 1435 /* 1436 * Calculate pagetable page index 1437 */ 1438 ptepindex = va >> PDRSHIFT; 1439 1440 /* 1441 * Get the page directory entry 1442 */ 1443 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1444 1445 /* 1446 * This supports switching from a 4MB page to a 1447 * normal 4K page. 1448 */ 1449 if (ptepa & PG_PS) { 1450 pmap->pm_pdir[ptepindex] = 0; 1451 ptepa = 0; 1452 pmap_invalidate_all(kernel_pmap); 1453 } 1454 1455 /* 1456 * If the page table page is mapped, we just increment the 1457 * hold count, and activate it. 1458 */ 1459 if (ptepa) { 1460 /* 1461 * In order to get the page table page, try the 1462 * hint first. 1463 */ 1464 if (pmap->pm_ptphint && 1465 (pmap->pm_ptphint->pindex == ptepindex)) { 1466 m = pmap->pm_ptphint; 1467 } else { 1468 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1469 pmap->pm_ptphint = m; 1470 } 1471 m->hold_count++; 1472 return m; 1473 } 1474 /* 1475 * Here if the pte page isn't mapped, or if it has been deallocated. 1476 */ 1477 return _pmap_allocpte(pmap, ptepindex); 1478} 1479 1480 1481/*************************************************** 1482* Pmap allocation/deallocation routines. 1483 ***************************************************/ 1484 1485/* 1486 * Release any resources held by the given physical map. 1487 * Called when a pmap initialized by pmap_pinit is being released. 1488 * Should only be called if the map contains no valid mappings. 1489 */ 1490void 1491pmap_release(pmap_t pmap) 1492{ 1493 vm_page_t p,n,ptdpg; 1494 vm_object_t object = pmap->pm_pteobj; 1495 int curgeneration; 1496 1497#if defined(DIAGNOSTIC) 1498 if (object->ref_count != 1) 1499 panic("pmap_release: pteobj reference count != 1"); 1500#endif 1501 1502 ptdpg = NULL; 1503 mtx_lock_spin(&allpmaps_lock); 1504 LIST_REMOVE(pmap, pm_list); 1505 mtx_unlock_spin(&allpmaps_lock); 1506retry: 1507 curgeneration = object->generation; 1508 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1509 n = TAILQ_NEXT(p, listq); 1510 if (p->pindex == PTDPTDI) { 1511 ptdpg = p; 1512 continue; 1513 } 1514 while (1) { 1515 if (!pmap_release_free_page(pmap, p) && 1516 (object->generation != curgeneration)) 1517 goto retry; 1518 } 1519 } 1520 1521 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1522 goto retry; 1523} 1524 1525static int 1526kvm_size(SYSCTL_HANDLER_ARGS) 1527{ 1528 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1529 1530 return sysctl_handle_long(oidp, &ksize, 0, req); 1531} 1532SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1533 0, 0, kvm_size, "IU", "Size of KVM"); 1534 1535static int 1536kvm_free(SYSCTL_HANDLER_ARGS) 1537{ 1538 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1539 1540 return sysctl_handle_long(oidp, &kfree, 0, req); 1541} 1542SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1543 0, 0, kvm_free, "IU", "Amount of KVM free"); 1544 1545/* 1546 * grow the number of kernel page table entries, if needed 1547 */ 1548void 1549pmap_growkernel(vm_offset_t addr) 1550{ 1551 struct pmap *pmap; 1552 int s; 1553 vm_offset_t ptppaddr; 1554 vm_page_t nkpg; 1555 pd_entry_t newpdir; 1556 1557 s = splhigh(); 1558 if (kernel_vm_end == 0) { 1559 kernel_vm_end = KERNBASE; 1560 nkpt = 0; 1561 while (pdir_pde(PTD, kernel_vm_end)) { 1562 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1563 nkpt++; 1564 } 1565 } 1566 addr = roundup2(addr, PAGE_SIZE * NPTEPG); 1567 while (kernel_vm_end < addr) { 1568 if (pdir_pde(PTD, kernel_vm_end)) { 1569 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1570 continue; 1571 } 1572 1573 /* 1574 * This index is bogus, but out of the way 1575 */ 1576 nkpg = vm_page_alloc(NULL, nkpt, 1577 VM_ALLOC_NOOBJ | VM_ALLOC_SYSTEM | VM_ALLOC_WIRED); 1578 if (!nkpg) 1579 panic("pmap_growkernel: no memory to grow kernel"); 1580 1581 nkpt++; 1582 1583 pmap_zero_page(nkpg); 1584 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1585 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1586 pdir_pde(PTD, kernel_vm_end) = newpdir; 1587 1588 mtx_lock_spin(&allpmaps_lock); 1589 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1590 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1591 } 1592 mtx_unlock_spin(&allpmaps_lock); 1593 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1594 } 1595 splx(s); 1596} 1597 1598 1599/*************************************************** 1600 * page management routines. 1601 ***************************************************/ 1602 1603/* 1604 * free the pv_entry back to the free list 1605 */ 1606static PMAP_INLINE void 1607free_pv_entry(pv_entry_t pv) 1608{ 1609 pv_entry_count--; 1610 uma_zfree(pvzone, pv); 1611} 1612 1613/* 1614 * get a new pv_entry, allocating a block from the system 1615 * when needed. 1616 * the memory allocation is performed bypassing the malloc code 1617 * because of the possibility of allocations at interrupt time. 1618 */ 1619static pv_entry_t 1620get_pv_entry(void) 1621{ 1622 pv_entry_count++; 1623 if (pv_entry_high_water && 1624 (pv_entry_count > pv_entry_high_water) && 1625 (pmap_pagedaemon_waken == 0)) { 1626 pmap_pagedaemon_waken = 1; 1627 wakeup (&vm_pages_needed); 1628 } 1629 return uma_zalloc(pvzone, M_NOWAIT); 1630} 1631 1632/* 1633 * If it is the first entry on the list, it is actually 1634 * in the header and we must copy the following entry up 1635 * to the header. Otherwise we must search the list for 1636 * the entry. In either case we free the now unused entry. 1637 */ 1638 1639static int 1640pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1641{ 1642 pv_entry_t pv; 1643 int rtval; 1644 int s; 1645 1646 s = splvm(); 1647 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1648 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1649 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1650 if (pmap == pv->pv_pmap && va == pv->pv_va) 1651 break; 1652 } 1653 } else { 1654 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1655 if (va == pv->pv_va) 1656 break; 1657 } 1658 } 1659 1660 rtval = 0; 1661 if (pv) { 1662 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1663 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1664 m->md.pv_list_count--; 1665 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1666 vm_page_flag_clear(m, PG_WRITEABLE); 1667 1668 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1669 free_pv_entry(pv); 1670 } 1671 1672 splx(s); 1673 return rtval; 1674} 1675 1676/* 1677 * Create a pv entry for page at pa for 1678 * (pmap, va). 1679 */ 1680static void 1681pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1682{ 1683 1684 int s; 1685 pv_entry_t pv; 1686 1687 s = splvm(); 1688 pv = get_pv_entry(); 1689 pv->pv_va = va; 1690 pv->pv_pmap = pmap; 1691 pv->pv_ptem = mpte; 1692 1693 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1694 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1695 m->md.pv_list_count++; 1696 1697 splx(s); 1698} 1699 1700/* 1701 * pmap_remove_pte: do the things to unmap a page in a process 1702 */ 1703static int 1704pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1705{ 1706 pt_entry_t oldpte; 1707 vm_page_t m; 1708 1709 oldpte = atomic_readandclear_int(ptq); 1710 if (oldpte & PG_W) 1711 pmap->pm_stats.wired_count -= 1; 1712 /* 1713 * Machines that don't support invlpg, also don't support 1714 * PG_G. 1715 */ 1716 if (oldpte & PG_G) 1717 pmap_invalidate_page(kernel_pmap, va); 1718 pmap->pm_stats.resident_count -= 1; 1719 if (oldpte & PG_MANAGED) { 1720 m = PHYS_TO_VM_PAGE(oldpte); 1721 if (oldpte & PG_M) { 1722#if defined(PMAP_DIAGNOSTIC) 1723 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1724 printf( 1725 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1726 va, oldpte); 1727 } 1728#endif 1729 if (pmap_track_modified(va)) 1730 vm_page_dirty(m); 1731 } 1732 if (oldpte & PG_A) 1733 vm_page_flag_set(m, PG_REFERENCED); 1734 return pmap_remove_entry(pmap, m, va); 1735 } else { 1736 return pmap_unuse_pt(pmap, va, NULL); 1737 } 1738 1739 return 0; 1740} 1741 1742/* 1743 * Remove a single page from a process address space 1744 */ 1745static void 1746pmap_remove_page(pmap_t pmap, vm_offset_t va) 1747{ 1748 register pt_entry_t *ptq; 1749 1750 /* 1751 * if there is no pte for this address, just skip it!!! 1752 */ 1753 if (*pmap_pde(pmap, va) == 0) { 1754 return; 1755 } 1756 1757 /* 1758 * get a local va for mappings for this pmap. 1759 */ 1760 ptq = get_ptbase(pmap) + i386_btop(va); 1761 if (*ptq) { 1762 (void) pmap_remove_pte(pmap, ptq, va); 1763 pmap_invalidate_page(pmap, va); 1764 } 1765 return; 1766} 1767 1768/* 1769 * Remove the given range of addresses from the specified map. 1770 * 1771 * It is assumed that the start and end are properly 1772 * rounded to the page size. 1773 */ 1774void 1775pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1776{ 1777 register pt_entry_t *ptbase; 1778 vm_offset_t pdnxt; 1779 pd_entry_t ptpaddr; 1780 vm_offset_t sindex, eindex; 1781 int anyvalid; 1782 1783 if (pmap == NULL) 1784 return; 1785 1786 if (pmap->pm_stats.resident_count == 0) 1787 return; 1788 1789 /* 1790 * special handling of removing one page. a very 1791 * common operation and easy to short circuit some 1792 * code. 1793 */ 1794 if ((sva + PAGE_SIZE == eva) && 1795 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1796 pmap_remove_page(pmap, sva); 1797 return; 1798 } 1799 1800 anyvalid = 0; 1801 1802 /* 1803 * Get a local virtual address for the mappings that are being 1804 * worked with. 1805 */ 1806 ptbase = get_ptbase(pmap); 1807 1808 sindex = i386_btop(sva); 1809 eindex = i386_btop(eva); 1810 1811 for (; sindex < eindex; sindex = pdnxt) { 1812 unsigned pdirindex; 1813 1814 /* 1815 * Calculate index for next page table. 1816 */ 1817 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1818 if (pmap->pm_stats.resident_count == 0) 1819 break; 1820 1821 pdirindex = sindex / NPDEPG; 1822 ptpaddr = pmap->pm_pdir[pdirindex]; 1823 if ((ptpaddr & PG_PS) != 0) { 1824 pmap->pm_pdir[pdirindex] = 0; 1825 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1826 anyvalid++; 1827 continue; 1828 } 1829 1830 /* 1831 * Weed out invalid mappings. Note: we assume that the page 1832 * directory table is always allocated, and in kernel virtual. 1833 */ 1834 if (ptpaddr == 0) 1835 continue; 1836 1837 /* 1838 * Limit our scan to either the end of the va represented 1839 * by the current page table page, or to the end of the 1840 * range being removed. 1841 */ 1842 if (pdnxt > eindex) { 1843 pdnxt = eindex; 1844 } 1845 1846 for (; sindex != pdnxt; sindex++) { 1847 vm_offset_t va; 1848 if (ptbase[sindex] == 0) { 1849 continue; 1850 } 1851 va = i386_ptob(sindex); 1852 1853 anyvalid++; 1854 if (pmap_remove_pte(pmap, ptbase + sindex, va)) 1855 break; 1856 } 1857 } 1858 1859 if (anyvalid) 1860 pmap_invalidate_all(pmap); 1861} 1862 1863/* 1864 * Routine: pmap_remove_all 1865 * Function: 1866 * Removes this physical page from 1867 * all physical maps in which it resides. 1868 * Reflects back modify bits to the pager. 1869 * 1870 * Notes: 1871 * Original versions of this routine were very 1872 * inefficient because they iteratively called 1873 * pmap_remove (slow...) 1874 */ 1875 1876void 1877pmap_remove_all(vm_page_t m) 1878{ 1879 register pv_entry_t pv; 1880 pt_entry_t *pte, tpte; 1881 int s; 1882 1883#if defined(PMAP_DIAGNOSTIC) 1884 /* 1885 * XXX This makes pmap_remove_all() illegal for non-managed pages! 1886 */ 1887 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1888 panic("pmap_remove_all: illegal for unmanaged page, va: 0x%x", 1889 VM_PAGE_TO_PHYS(m)); 1890 } 1891#endif 1892 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1893 s = splvm(); 1894 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1895 pv->pv_pmap->pm_stats.resident_count--; 1896 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1897 tpte = atomic_readandclear_int(pte); 1898 if (tpte & PG_W) 1899 pv->pv_pmap->pm_stats.wired_count--; 1900 if (tpte & PG_A) 1901 vm_page_flag_set(m, PG_REFERENCED); 1902 1903 /* 1904 * Update the vm_page_t clean and reference bits. 1905 */ 1906 if (tpte & PG_M) { 1907#if defined(PMAP_DIAGNOSTIC) 1908 if (pmap_nw_modified((pt_entry_t) tpte)) { 1909 printf( 1910 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1911 pv->pv_va, tpte); 1912 } 1913#endif 1914 if (pmap_track_modified(pv->pv_va)) 1915 vm_page_dirty(m); 1916 } 1917 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1918 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1919 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1920 m->md.pv_list_count--; 1921 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1922 free_pv_entry(pv); 1923 } 1924 vm_page_flag_clear(m, PG_WRITEABLE); 1925 splx(s); 1926} 1927 1928/* 1929 * Set the physical protection on the 1930 * specified range of this map as requested. 1931 */ 1932void 1933pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1934{ 1935 register pt_entry_t *ptbase; 1936 vm_offset_t pdnxt; 1937 pd_entry_t ptpaddr; 1938 vm_offset_t sindex, eindex; 1939 int anychanged; 1940 1941 if (pmap == NULL) 1942 return; 1943 1944 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1945 pmap_remove(pmap, sva, eva); 1946 return; 1947 } 1948 1949 if (prot & VM_PROT_WRITE) 1950 return; 1951 1952 anychanged = 0; 1953 1954 ptbase = get_ptbase(pmap); 1955 1956 sindex = i386_btop(sva); 1957 eindex = i386_btop(eva); 1958 1959 for (; sindex < eindex; sindex = pdnxt) { 1960 1961 unsigned pdirindex; 1962 1963 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1964 1965 pdirindex = sindex / NPDEPG; 1966 ptpaddr = pmap->pm_pdir[pdirindex]; 1967 if ((ptpaddr & PG_PS) != 0) { 1968 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1969 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1970 anychanged++; 1971 continue; 1972 } 1973 1974 /* 1975 * Weed out invalid mappings. Note: we assume that the page 1976 * directory table is always allocated, and in kernel virtual. 1977 */ 1978 if (ptpaddr == 0) 1979 continue; 1980 1981 if (pdnxt > eindex) { 1982 pdnxt = eindex; 1983 } 1984 1985 for (; sindex != pdnxt; sindex++) { 1986 1987 pt_entry_t pbits; 1988 vm_page_t m; 1989 1990 pbits = ptbase[sindex]; 1991 1992 if (pbits & PG_MANAGED) { 1993 m = NULL; 1994 if (pbits & PG_A) { 1995 m = PHYS_TO_VM_PAGE(pbits); 1996 vm_page_flag_set(m, PG_REFERENCED); 1997 pbits &= ~PG_A; 1998 } 1999 if (pbits & PG_M) { 2000 if (pmap_track_modified(i386_ptob(sindex))) { 2001 if (m == NULL) 2002 m = PHYS_TO_VM_PAGE(pbits); 2003 vm_page_dirty(m); 2004 pbits &= ~PG_M; 2005 } 2006 } 2007 } 2008 2009 pbits &= ~PG_RW; 2010 2011 if (pbits != ptbase[sindex]) { 2012 ptbase[sindex] = pbits; 2013 anychanged = 1; 2014 } 2015 } 2016 } 2017 if (anychanged) 2018 pmap_invalidate_all(pmap); 2019} 2020 2021/* 2022 * Insert the given physical page (p) at 2023 * the specified virtual address (v) in the 2024 * target physical map with the protection requested. 2025 * 2026 * If specified, the page will be wired down, meaning 2027 * that the related pte can not be reclaimed. 2028 * 2029 * NB: This is the only routine which MAY NOT lazy-evaluate 2030 * or lose information. That is, this routine must actually 2031 * insert this page into the given map NOW. 2032 */ 2033void 2034pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2035 boolean_t wired) 2036{ 2037 vm_offset_t pa; 2038 register pt_entry_t *pte; 2039 vm_offset_t opa; 2040 pt_entry_t origpte, newpte; 2041 vm_page_t mpte; 2042 2043 if (pmap == NULL) 2044 return; 2045 2046 va &= PG_FRAME; 2047#ifdef PMAP_DIAGNOSTIC 2048 if (va > VM_MAX_KERNEL_ADDRESS) 2049 panic("pmap_enter: toobig"); 2050 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2051 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2052#endif 2053 2054 mpte = NULL; 2055 /* 2056 * In the case that a page table page is not 2057 * resident, we are creating it here. 2058 */ 2059 if (va < VM_MAXUSER_ADDRESS) { 2060 mpte = pmap_allocpte(pmap, va); 2061 } 2062#if 0 && defined(PMAP_DIAGNOSTIC) 2063 else { 2064 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2065 origpte = *pdeaddr; 2066 if ((origpte & PG_V) == 0) { 2067 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2068 pmap->pm_pdir[PTDPTDI], origpte, va); 2069 } 2070 } 2071#endif 2072 2073 pte = pmap_pte(pmap, va); 2074 2075 /* 2076 * Page Directory table entry not valid, we need a new PT page 2077 */ 2078 if (pte == NULL) { 2079 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2080 (void *)pmap->pm_pdir[PTDPTDI], va); 2081 } 2082 2083 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2084 origpte = *(vm_offset_t *)pte; 2085 opa = origpte & PG_FRAME; 2086 2087 if (origpte & PG_PS) 2088 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2089 2090 /* 2091 * Mapping has not changed, must be protection or wiring change. 2092 */ 2093 if (origpte && (opa == pa)) { 2094 /* 2095 * Wiring change, just update stats. We don't worry about 2096 * wiring PT pages as they remain resident as long as there 2097 * are valid mappings in them. Hence, if a user page is wired, 2098 * the PT page will be also. 2099 */ 2100 if (wired && ((origpte & PG_W) == 0)) 2101 pmap->pm_stats.wired_count++; 2102 else if (!wired && (origpte & PG_W)) 2103 pmap->pm_stats.wired_count--; 2104 2105#if defined(PMAP_DIAGNOSTIC) 2106 if (pmap_nw_modified((pt_entry_t) origpte)) { 2107 printf( 2108 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2109 va, origpte); 2110 } 2111#endif 2112 2113 /* 2114 * Remove extra pte reference 2115 */ 2116 if (mpte) 2117 mpte->hold_count--; 2118 2119 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2120 if ((origpte & PG_RW) == 0) { 2121 *pte |= PG_RW; 2122 pmap_invalidate_page(pmap, va); 2123 } 2124 return; 2125 } 2126 2127 /* 2128 * We might be turning off write access to the page, 2129 * so we go ahead and sense modify status. 2130 */ 2131 if (origpte & PG_MANAGED) { 2132 if ((origpte & PG_M) && pmap_track_modified(va)) { 2133 vm_page_t om; 2134 om = PHYS_TO_VM_PAGE(opa); 2135 vm_page_dirty(om); 2136 } 2137 pa |= PG_MANAGED; 2138 } 2139 goto validate; 2140 } 2141 /* 2142 * Mapping has changed, invalidate old range and fall through to 2143 * handle validating new mapping. 2144 */ 2145 if (opa) { 2146 int err; 2147 vm_page_lock_queues(); 2148 err = pmap_remove_pte(pmap, pte, va); 2149 vm_page_unlock_queues(); 2150 if (err) 2151 panic("pmap_enter: pte vanished, va: 0x%x", va); 2152 } 2153 2154 /* 2155 * Enter on the PV list if part of our managed memory. Note that we 2156 * raise IPL while manipulating pv_table since pmap_enter can be 2157 * called at interrupt time. 2158 */ 2159 if (pmap_initialized && 2160 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2161 pmap_insert_entry(pmap, va, mpte, m); 2162 pa |= PG_MANAGED; 2163 } 2164 2165 /* 2166 * Increment counters 2167 */ 2168 pmap->pm_stats.resident_count++; 2169 if (wired) 2170 pmap->pm_stats.wired_count++; 2171 2172validate: 2173 /* 2174 * Now validate mapping with desired protection/wiring. 2175 */ 2176 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2177 2178 if (wired) 2179 newpte |= PG_W; 2180 if (va < VM_MAXUSER_ADDRESS) 2181 newpte |= PG_U; 2182 if (pmap == kernel_pmap) 2183 newpte |= pgeflag; 2184 2185 /* 2186 * if the mapping or permission bits are different, we need 2187 * to update the pte. 2188 */ 2189 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2190 *pte = newpte | PG_A; 2191 /*if (origpte)*/ { 2192 pmap_invalidate_page(pmap, va); 2193 } 2194 } 2195} 2196 2197/* 2198 * this code makes some *MAJOR* assumptions: 2199 * 1. Current pmap & pmap exists. 2200 * 2. Not wired. 2201 * 3. Read access. 2202 * 4. No page table pages. 2203 * 5. Tlbflush is deferred to calling procedure. 2204 * 6. Page IS managed. 2205 * but is *MUCH* faster than pmap_enter... 2206 */ 2207 2208static vm_page_t 2209pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2210{ 2211 pt_entry_t *pte; 2212 vm_offset_t pa; 2213 2214 /* 2215 * In the case that a page table page is not 2216 * resident, we are creating it here. 2217 */ 2218 if (va < VM_MAXUSER_ADDRESS) { 2219 unsigned ptepindex; 2220 pd_entry_t ptepa; 2221 2222 /* 2223 * Calculate pagetable page index 2224 */ 2225 ptepindex = va >> PDRSHIFT; 2226 if (mpte && (mpte->pindex == ptepindex)) { 2227 mpte->hold_count++; 2228 } else { 2229retry: 2230 /* 2231 * Get the page directory entry 2232 */ 2233 ptepa = pmap->pm_pdir[ptepindex]; 2234 2235 /* 2236 * If the page table page is mapped, we just increment 2237 * the hold count, and activate it. 2238 */ 2239 if (ptepa) { 2240 if (ptepa & PG_PS) 2241 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2242 if (pmap->pm_ptphint && 2243 (pmap->pm_ptphint->pindex == ptepindex)) { 2244 mpte = pmap->pm_ptphint; 2245 } else { 2246 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2247 pmap->pm_ptphint = mpte; 2248 } 2249 if (mpte == NULL) 2250 goto retry; 2251 mpte->hold_count++; 2252 } else { 2253 mpte = _pmap_allocpte(pmap, ptepindex); 2254 } 2255 } 2256 } else { 2257 mpte = NULL; 2258 } 2259 2260 /* 2261 * This call to vtopte makes the assumption that we are 2262 * entering the page into the current pmap. In order to support 2263 * quick entry into any pmap, one would likely use pmap_pte_quick. 2264 * But that isn't as quick as vtopte. 2265 */ 2266 pte = vtopte(va); 2267 if (*pte) { 2268 if (mpte != NULL) { 2269 vm_page_lock_queues(); 2270 pmap_unwire_pte_hold(pmap, mpte); 2271 vm_page_unlock_queues(); 2272 } 2273 return 0; 2274 } 2275 2276 /* 2277 * Enter on the PV list if part of our managed memory. Note that we 2278 * raise IPL while manipulating pv_table since pmap_enter can be 2279 * called at interrupt time. 2280 */ 2281 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2282 pmap_insert_entry(pmap, va, mpte, m); 2283 2284 /* 2285 * Increment counters 2286 */ 2287 pmap->pm_stats.resident_count++; 2288 2289 pa = VM_PAGE_TO_PHYS(m); 2290 2291 /* 2292 * Now validate mapping with RO protection 2293 */ 2294 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2295 *pte = pa | PG_V | PG_U; 2296 else 2297 *pte = pa | PG_V | PG_U | PG_MANAGED; 2298 2299 return mpte; 2300} 2301 2302/* 2303 * Make a temporary mapping for a physical address. This is only intended 2304 * to be used for panic dumps. 2305 */ 2306void * 2307pmap_kenter_temporary(vm_offset_t pa, int i) 2308{ 2309 vm_offset_t va; 2310 2311 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE); 2312 pmap_kenter(va, pa); 2313#ifndef I386_CPU 2314 invlpg(va); 2315#else 2316 invltlb(); 2317#endif 2318 return ((void *)crashdumpmap); 2319} 2320 2321#define MAX_INIT_PT (96) 2322/* 2323 * pmap_object_init_pt preloads the ptes for a given object 2324 * into the specified pmap. This eliminates the blast of soft 2325 * faults on process startup and immediately after an mmap. 2326 */ 2327void 2328pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2329 vm_object_t object, vm_pindex_t pindex, 2330 vm_size_t size, int limit) 2331{ 2332 vm_offset_t tmpidx; 2333 int psize; 2334 vm_page_t p, mpte; 2335 2336 if (pmap == NULL || object == NULL) 2337 return; 2338 2339 /* 2340 * This code maps large physical mmap regions into the 2341 * processor address space. Note that some shortcuts 2342 * are taken, but the code works. 2343 */ 2344 if (pseflag && (object->type == OBJT_DEVICE) && 2345 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2346 int i; 2347 vm_page_t m[1]; 2348 unsigned int ptepindex; 2349 int npdes; 2350 pd_entry_t ptepa; 2351 2352 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2353 return; 2354 2355retry: 2356 p = vm_page_lookup(object, pindex); 2357 if (p != NULL) { 2358 vm_page_lock_queues(); 2359 if (vm_page_sleep_if_busy(p, FALSE, "init4p")) 2360 goto retry; 2361 } else { 2362 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2363 if (p == NULL) 2364 return; 2365 m[0] = p; 2366 2367 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2368 vm_page_lock_queues(); 2369 vm_page_free(p); 2370 vm_page_unlock_queues(); 2371 return; 2372 } 2373 2374 p = vm_page_lookup(object, pindex); 2375 vm_page_lock_queues(); 2376 vm_page_wakeup(p); 2377 } 2378 vm_page_unlock_queues(); 2379 2380 ptepa = VM_PAGE_TO_PHYS(p); 2381 if (ptepa & (NBPDR - 1)) { 2382 return; 2383 } 2384 2385 p->valid = VM_PAGE_BITS_ALL; 2386 2387 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2388 npdes = size >> PDRSHIFT; 2389 for(i = 0; i < npdes; i++) { 2390 pmap->pm_pdir[ptepindex] = 2391 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2392 ptepa += NBPDR; 2393 ptepindex += 1; 2394 } 2395 pmap_invalidate_all(kernel_pmap); 2396 return; 2397 } 2398 2399 psize = i386_btop(size); 2400 2401 if ((object->type != OBJT_VNODE) || 2402 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2403 (object->resident_page_count > MAX_INIT_PT))) { 2404 return; 2405 } 2406 2407 if (psize + pindex > object->size) { 2408 if (object->size < pindex) 2409 return; 2410 psize = object->size - pindex; 2411 } 2412 2413 mpte = NULL; 2414 2415 if ((p = TAILQ_FIRST(&object->memq)) != NULL) { 2416 if (p->pindex < pindex) { 2417 p = vm_page_splay(pindex, object->root); 2418 if ((object->root = p)->pindex < pindex) 2419 p = TAILQ_NEXT(p, listq); 2420 } 2421 } 2422 /* 2423 * Assert: the variable p is either (1) the page with the 2424 * least pindex greater than or equal to the parameter pindex 2425 * or (2) NULL. 2426 */ 2427 for (; 2428 p != NULL && (tmpidx = p->pindex - pindex) < psize; 2429 p = TAILQ_NEXT(p, listq)) { 2430 /* 2431 * don't allow an madvise to blow away our really 2432 * free pages allocating pv entries. 2433 */ 2434 if ((limit & MAP_PREFAULT_MADVISE) && 2435 cnt.v_free_count < cnt.v_free_reserved) { 2436 break; 2437 } 2438 vm_page_lock_queues(); 2439 if ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL && 2440 (p->busy == 0) && 2441 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2442 if ((p->queue - p->pc) == PQ_CACHE) 2443 vm_page_deactivate(p); 2444 vm_page_busy(p); 2445 vm_page_unlock_queues(); 2446 mpte = pmap_enter_quick(pmap, 2447 addr + i386_ptob(tmpidx), p, mpte); 2448 vm_page_lock_queues(); 2449 vm_page_wakeup(p); 2450 } 2451 vm_page_unlock_queues(); 2452 } 2453 return; 2454} 2455 2456/* 2457 * pmap_prefault provides a quick way of clustering 2458 * pagefaults into a processes address space. It is a "cousin" 2459 * of pmap_object_init_pt, except it runs at page fault time instead 2460 * of mmap time. 2461 */ 2462#define PFBAK 4 2463#define PFFOR 4 2464#define PAGEORDER_SIZE (PFBAK+PFFOR) 2465 2466static int pmap_prefault_pageorder[] = { 2467 -1 * PAGE_SIZE, 1 * PAGE_SIZE, 2468 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2469 -3 * PAGE_SIZE, 3 * PAGE_SIZE, 2470 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2471}; 2472 2473void 2474pmap_prefault(pmap, addra, entry) 2475 pmap_t pmap; 2476 vm_offset_t addra; 2477 vm_map_entry_t entry; 2478{ 2479 int i; 2480 vm_offset_t starta; 2481 vm_offset_t addr; 2482 vm_pindex_t pindex; 2483 vm_page_t m, mpte; 2484 vm_object_t object; 2485 2486 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2487 return; 2488 2489 object = entry->object.vm_object; 2490 2491 starta = addra - PFBAK * PAGE_SIZE; 2492 if (starta < entry->start) { 2493 starta = entry->start; 2494 } else if (starta > addra) { 2495 starta = 0; 2496 } 2497 2498 mpte = NULL; 2499 for (i = 0; i < PAGEORDER_SIZE; i++) { 2500 vm_object_t lobject; 2501 pt_entry_t *pte; 2502 2503 addr = addra + pmap_prefault_pageorder[i]; 2504 if (addr > addra + (PFFOR * PAGE_SIZE)) 2505 addr = 0; 2506 2507 if (addr < starta || addr >= entry->end) 2508 continue; 2509 2510 if ((*pmap_pde(pmap, addr)) == 0) 2511 continue; 2512 2513 pte = vtopte(addr); 2514 if (*pte) 2515 continue; 2516 2517 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2518 lobject = object; 2519 for (m = vm_page_lookup(lobject, pindex); 2520 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2521 lobject = lobject->backing_object) { 2522 if (lobject->backing_object_offset & PAGE_MASK) 2523 break; 2524 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2525 m = vm_page_lookup(lobject->backing_object, pindex); 2526 } 2527 2528 /* 2529 * give-up when a page is not in memory 2530 */ 2531 if (m == NULL) 2532 break; 2533 vm_page_lock_queues(); 2534 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2535 (m->busy == 0) && 2536 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2537 2538 if ((m->queue - m->pc) == PQ_CACHE) { 2539 vm_page_deactivate(m); 2540 } 2541 vm_page_busy(m); 2542 vm_page_unlock_queues(); 2543 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2544 vm_page_lock_queues(); 2545 vm_page_wakeup(m); 2546 } 2547 vm_page_unlock_queues(); 2548 } 2549} 2550 2551/* 2552 * Routine: pmap_change_wiring 2553 * Function: Change the wiring attribute for a map/virtual-address 2554 * pair. 2555 * In/out conditions: 2556 * The mapping must already exist in the pmap. 2557 */ 2558void 2559pmap_change_wiring(pmap, va, wired) 2560 register pmap_t pmap; 2561 vm_offset_t va; 2562 boolean_t wired; 2563{ 2564 register pt_entry_t *pte; 2565 2566 if (pmap == NULL) 2567 return; 2568 2569 pte = pmap_pte(pmap, va); 2570 2571 if (wired && !pmap_pte_w(pte)) 2572 pmap->pm_stats.wired_count++; 2573 else if (!wired && pmap_pte_w(pte)) 2574 pmap->pm_stats.wired_count--; 2575 2576 /* 2577 * Wiring is not a hardware characteristic so there is no need to 2578 * invalidate TLB. 2579 */ 2580 pmap_pte_set_w(pte, wired); 2581} 2582 2583 2584 2585/* 2586 * Copy the range specified by src_addr/len 2587 * from the source map to the range dst_addr/len 2588 * in the destination map. 2589 * 2590 * This routine is only advisory and need not do anything. 2591 */ 2592 2593void 2594pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2595 vm_offset_t src_addr) 2596{ 2597 vm_offset_t addr; 2598 vm_offset_t end_addr = src_addr + len; 2599 vm_offset_t pdnxt; 2600 pd_entry_t src_frame, dst_frame; 2601 vm_page_t m; 2602 2603 if (dst_addr != src_addr) 2604 return; 2605 2606 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2607 if (src_frame != (PTDpde & PG_FRAME)) 2608 return; 2609 2610 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2611 for (addr = src_addr; addr < end_addr; addr = pdnxt) { 2612 pt_entry_t *src_pte, *dst_pte; 2613 vm_page_t dstmpte, srcmpte; 2614 pd_entry_t srcptepaddr; 2615 unsigned ptepindex; 2616 2617 if (addr >= UPT_MIN_ADDRESS) 2618 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2619 2620 /* 2621 * Don't let optional prefaulting of pages make us go 2622 * way below the low water mark of free pages or way 2623 * above high water mark of used pv entries. 2624 */ 2625 if (cnt.v_free_count < cnt.v_free_reserved || 2626 pv_entry_count > pv_entry_high_water) 2627 break; 2628 2629 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2630 ptepindex = addr >> PDRSHIFT; 2631 2632 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2633 if (srcptepaddr == 0) 2634 continue; 2635 2636 if (srcptepaddr & PG_PS) { 2637 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2638 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2639 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2640 } 2641 continue; 2642 } 2643 2644 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2645 if ((srcmpte == NULL) || 2646 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2647 continue; 2648 2649 if (pdnxt > end_addr) 2650 pdnxt = end_addr; 2651 2652 /* 2653 * Have to recheck this before every avtopte() call below 2654 * in case we have blocked and something else used APTDpde. 2655 */ 2656 if (dst_frame != (APTDpde & PG_FRAME)) { 2657 APTDpde = dst_frame | PG_RW | PG_V; 2658 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 2659 } 2660 src_pte = vtopte(addr); 2661 dst_pte = avtopte(addr); 2662 while (addr < pdnxt) { 2663 pt_entry_t ptetemp; 2664 ptetemp = *src_pte; 2665 /* 2666 * we only virtual copy managed pages 2667 */ 2668 if ((ptetemp & PG_MANAGED) != 0) { 2669 /* 2670 * We have to check after allocpte for the 2671 * pte still being around... allocpte can 2672 * block. 2673 */ 2674 dstmpte = pmap_allocpte(dst_pmap, addr); 2675 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2676 /* 2677 * Clear the modified and 2678 * accessed (referenced) bits 2679 * during the copy. 2680 */ 2681 m = PHYS_TO_VM_PAGE(ptetemp); 2682 *dst_pte = ptetemp & ~(PG_M | PG_A); 2683 dst_pmap->pm_stats.resident_count++; 2684 pmap_insert_entry(dst_pmap, addr, 2685 dstmpte, m); 2686 } else { 2687 vm_page_lock_queues(); 2688 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2689 vm_page_unlock_queues(); 2690 } 2691 if (dstmpte->hold_count >= srcmpte->hold_count) 2692 break; 2693 } 2694 addr += PAGE_SIZE; 2695 src_pte++; 2696 dst_pte++; 2697 } 2698 } 2699} 2700 2701#ifdef SMP 2702 2703/* 2704 * pmap_zpi_switchin*() 2705 * 2706 * These functions allow us to avoid doing IPIs alltogether in certain 2707 * temporary page-mapping situations (page zeroing). Instead to deal 2708 * with being preempted and moved onto a different cpu we invalidate 2709 * the page when the scheduler switches us in. This does not occur 2710 * very often so we remain relatively optimal with very little effort. 2711 */ 2712static void 2713pmap_zpi_switchin12(void) 2714{ 2715 invlpg((u_int)CADDR1); 2716 invlpg((u_int)CADDR2); 2717} 2718 2719static void 2720pmap_zpi_switchin2(void) 2721{ 2722 invlpg((u_int)CADDR2); 2723} 2724 2725static void 2726pmap_zpi_switchin3(void) 2727{ 2728 invlpg((u_int)CADDR3); 2729} 2730 2731#endif 2732 2733/* 2734 * pmap_zero_page zeros the specified hardware page by mapping 2735 * the page into KVM and using bzero to clear its contents. 2736 */ 2737void 2738pmap_zero_page(vm_page_t m) 2739{ 2740 vm_offset_t phys; 2741 2742 phys = VM_PAGE_TO_PHYS(m); 2743 if (*CMAP2) 2744 panic("pmap_zero_page: CMAP2 busy"); 2745 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2746#ifdef I386_CPU 2747 invltlb(); 2748#else 2749#ifdef SMP 2750 curthread->td_switchin = pmap_zpi_switchin2; 2751#endif 2752 invlpg((u_int)CADDR2); 2753#endif 2754#if defined(I686_CPU) 2755 if (cpu_class == CPUCLASS_686) 2756 i686_pagezero(CADDR2); 2757 else 2758#endif 2759 bzero(CADDR2, PAGE_SIZE); 2760#ifdef SMP 2761 curthread->td_switchin = NULL; 2762#endif 2763 *CMAP2 = 0; 2764} 2765 2766/* 2767 * pmap_zero_page_area zeros the specified hardware page by mapping 2768 * the page into KVM and using bzero to clear its contents. 2769 * 2770 * off and size may not cover an area beyond a single hardware page. 2771 */ 2772void 2773pmap_zero_page_area(vm_page_t m, int off, int size) 2774{ 2775 vm_offset_t phys; 2776 2777 phys = VM_PAGE_TO_PHYS(m); 2778 if (*CMAP2) 2779 panic("pmap_zero_page: CMAP2 busy"); 2780 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2781#ifdef I386_CPU 2782 invltlb(); 2783#else 2784#ifdef SMP 2785 curthread->td_switchin = pmap_zpi_switchin2; 2786#endif 2787 invlpg((u_int)CADDR2); 2788#endif 2789#if defined(I686_CPU) 2790 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2791 i686_pagezero(CADDR2); 2792 else 2793#endif 2794 bzero((char *)CADDR2 + off, size); 2795#ifdef SMP 2796 curthread->td_switchin = NULL; 2797#endif 2798 *CMAP2 = 0; 2799} 2800 2801/* 2802 * pmap_zero_page_idle zeros the specified hardware page by mapping 2803 * the page into KVM and using bzero to clear its contents. This 2804 * is intended to be called from the vm_pagezero process only and 2805 * outside of Giant. 2806 */ 2807void 2808pmap_zero_page_idle(vm_page_t m) 2809{ 2810 vm_offset_t phys; 2811 2812 phys = VM_PAGE_TO_PHYS(m); 2813 if (*CMAP3) 2814 panic("pmap_zero_page: CMAP3 busy"); 2815 *CMAP3 = PG_V | PG_RW | phys | PG_A | PG_M; 2816#ifdef I386_CPU 2817 invltlb(); 2818#else 2819#ifdef SMP 2820 curthread->td_switchin = pmap_zpi_switchin3; 2821#endif 2822 invlpg((u_int)CADDR3); 2823#endif 2824#if defined(I686_CPU) 2825 if (cpu_class == CPUCLASS_686) 2826 i686_pagezero(CADDR3); 2827 else 2828#endif 2829 bzero(CADDR3, PAGE_SIZE); 2830#ifdef SMP 2831 curthread->td_switchin = NULL; 2832#endif 2833 *CMAP3 = 0; 2834} 2835 2836/* 2837 * pmap_copy_page copies the specified (machine independent) 2838 * page by mapping the page into virtual memory and using 2839 * bcopy to copy the page, one machine dependent page at a 2840 * time. 2841 */ 2842void 2843pmap_copy_page(vm_page_t src, vm_page_t dst) 2844{ 2845 2846 if (*CMAP1) 2847 panic("pmap_copy_page: CMAP1 busy"); 2848 if (*CMAP2) 2849 panic("pmap_copy_page: CMAP2 busy"); 2850 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2851 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2852#ifdef I386_CPU 2853 invltlb(); 2854#else 2855#ifdef SMP 2856 curthread->td_switchin = pmap_zpi_switchin12; 2857#endif 2858 invlpg((u_int)CADDR1); 2859 invlpg((u_int)CADDR2); 2860#endif 2861 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2862#ifdef SMP 2863 curthread->td_switchin = NULL; 2864#endif 2865 *CMAP1 = 0; 2866 *CMAP2 = 0; 2867} 2868 2869/* 2870 * Returns true if the pmap's pv is one of the first 2871 * 16 pvs linked to from this page. This count may 2872 * be changed upwards or downwards in the future; it 2873 * is only necessary that true be returned for a small 2874 * subset of pmaps for proper page aging. 2875 */ 2876boolean_t 2877pmap_page_exists_quick(pmap, m) 2878 pmap_t pmap; 2879 vm_page_t m; 2880{ 2881 pv_entry_t pv; 2882 int loops = 0; 2883 int s; 2884 2885 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2886 return FALSE; 2887 2888 s = splvm(); 2889 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 2890 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2891 if (pv->pv_pmap == pmap) { 2892 splx(s); 2893 return TRUE; 2894 } 2895 loops++; 2896 if (loops >= 16) 2897 break; 2898 } 2899 splx(s); 2900 return (FALSE); 2901} 2902 2903#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2904/* 2905 * Remove all pages from specified address space 2906 * this aids process exit speeds. Also, this code 2907 * is special cased for current process only, but 2908 * can have the more generic (and slightly slower) 2909 * mode enabled. This is much faster than pmap_remove 2910 * in the case of running down an entire address space. 2911 */ 2912void 2913pmap_remove_pages(pmap, sva, eva) 2914 pmap_t pmap; 2915 vm_offset_t sva, eva; 2916{ 2917 pt_entry_t *pte, tpte; 2918 vm_page_t m; 2919 pv_entry_t pv, npv; 2920 int s; 2921 2922#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2923 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2924 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2925 return; 2926 } 2927#endif 2928 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 2929 s = splvm(); 2930 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2931 2932 if (pv->pv_va >= eva || pv->pv_va < sva) { 2933 npv = TAILQ_NEXT(pv, pv_plist); 2934 continue; 2935 } 2936 2937#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2938 pte = vtopte(pv->pv_va); 2939#else 2940 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2941#endif 2942 tpte = *pte; 2943 2944 if (tpte == 0) { 2945 printf("TPTE at %p IS ZERO @ VA %08x\n", 2946 pte, pv->pv_va); 2947 panic("bad pte"); 2948 } 2949 2950/* 2951 * We cannot remove wired pages from a process' mapping at this time 2952 */ 2953 if (tpte & PG_W) { 2954 npv = TAILQ_NEXT(pv, pv_plist); 2955 continue; 2956 } 2957 2958 m = PHYS_TO_VM_PAGE(tpte); 2959 KASSERT(m->phys_addr == (tpte & PG_FRAME), 2960 ("vm_page_t %p phys_addr mismatch %08x %08x", 2961 m, m->phys_addr, tpte)); 2962 2963 KASSERT(m < &vm_page_array[vm_page_array_size], 2964 ("pmap_remove_pages: bad tpte %x", tpte)); 2965 2966 pv->pv_pmap->pm_stats.resident_count--; 2967 2968 *pte = 0; 2969 2970 /* 2971 * Update the vm_page_t clean and reference bits. 2972 */ 2973 if (tpte & PG_M) { 2974 vm_page_dirty(m); 2975 } 2976 2977 npv = TAILQ_NEXT(pv, pv_plist); 2978 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 2979 2980 m->md.pv_list_count--; 2981 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 2982 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 2983 vm_page_flag_clear(m, PG_WRITEABLE); 2984 } 2985 2986 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 2987 free_pv_entry(pv); 2988 } 2989 splx(s); 2990 pmap_invalidate_all(pmap); 2991} 2992 2993/* 2994 * pmap_is_modified: 2995 * 2996 * Return whether or not the specified physical page was modified 2997 * in any physical maps. 2998 */ 2999boolean_t 3000pmap_is_modified(vm_page_t m) 3001{ 3002 pv_entry_t pv; 3003 pt_entry_t *pte; 3004 int s; 3005 3006 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3007 return FALSE; 3008 3009 s = splvm(); 3010 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 3011 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3012 /* 3013 * if the bit being tested is the modified bit, then 3014 * mark clean_map and ptes as never 3015 * modified. 3016 */ 3017 if (!pmap_track_modified(pv->pv_va)) 3018 continue; 3019#if defined(PMAP_DIAGNOSTIC) 3020 if (!pv->pv_pmap) { 3021 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3022 continue; 3023 } 3024#endif 3025 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3026 if (*pte & PG_M) { 3027 splx(s); 3028 return TRUE; 3029 } 3030 } 3031 splx(s); 3032 return (FALSE); 3033} 3034 3035/* 3036 * this routine is used to modify bits in ptes 3037 */ 3038static __inline void 3039pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3040{ 3041 register pv_entry_t pv; 3042 register pt_entry_t *pte; 3043 int s; 3044 3045 if (!pmap_initialized || (m->flags & PG_FICTITIOUS) || 3046 (!setem && bit == PG_RW && (m->flags & PG_WRITEABLE) == 0)) 3047 return; 3048 3049 s = splvm(); 3050 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 3051 /* 3052 * Loop over all current mappings setting/clearing as appropos If 3053 * setting RO do we need to clear the VAC? 3054 */ 3055 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3056 /* 3057 * don't write protect pager mappings 3058 */ 3059 if (!setem && (bit == PG_RW)) { 3060 if (!pmap_track_modified(pv->pv_va)) 3061 continue; 3062 } 3063 3064#if defined(PMAP_DIAGNOSTIC) 3065 if (!pv->pv_pmap) { 3066 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3067 continue; 3068 } 3069#endif 3070 3071 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3072 3073 if (setem) { 3074 *pte |= bit; 3075 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3076 } else { 3077 pt_entry_t pbits = *pte; 3078 if (pbits & bit) { 3079 if (bit == PG_RW) { 3080 if (pbits & PG_M) { 3081 vm_page_dirty(m); 3082 } 3083 *pte = pbits & ~(PG_M|PG_RW); 3084 } else { 3085 *pte = pbits & ~bit; 3086 } 3087 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3088 } 3089 } 3090 } 3091 if (!setem && bit == PG_RW) 3092 vm_page_flag_clear(m, PG_WRITEABLE); 3093 splx(s); 3094} 3095 3096/* 3097 * pmap_page_protect: 3098 * 3099 * Lower the permission for all mappings to a given page. 3100 */ 3101void 3102pmap_page_protect(vm_page_t m, vm_prot_t prot) 3103{ 3104 if ((prot & VM_PROT_WRITE) == 0) { 3105 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3106 pmap_changebit(m, PG_RW, FALSE); 3107 } else { 3108 pmap_remove_all(m); 3109 } 3110 } 3111} 3112 3113vm_offset_t 3114pmap_phys_address(ppn) 3115 int ppn; 3116{ 3117 return (i386_ptob(ppn)); 3118} 3119 3120/* 3121 * pmap_ts_referenced: 3122 * 3123 * Return a count of reference bits for a page, clearing those bits. 3124 * It is not necessary for every reference bit to be cleared, but it 3125 * is necessary that 0 only be returned when there are truly no 3126 * reference bits set. 3127 * 3128 * XXX: The exact number of bits to check and clear is a matter that 3129 * should be tested and standardized at some point in the future for 3130 * optimal aging of shared pages. 3131 */ 3132int 3133pmap_ts_referenced(vm_page_t m) 3134{ 3135 register pv_entry_t pv, pvf, pvn; 3136 pt_entry_t *pte; 3137 int s; 3138 int rtval = 0; 3139 3140 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3141 return (rtval); 3142 3143 s = splvm(); 3144 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 3145 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3146 3147 pvf = pv; 3148 3149 do { 3150 pvn = TAILQ_NEXT(pv, pv_list); 3151 3152 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3153 3154 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3155 3156 if (!pmap_track_modified(pv->pv_va)) 3157 continue; 3158 3159 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3160 3161 if (pte && (*pte & PG_A)) { 3162 *pte &= ~PG_A; 3163 3164 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3165 3166 rtval++; 3167 if (rtval > 4) { 3168 break; 3169 } 3170 } 3171 } while ((pv = pvn) != NULL && pv != pvf); 3172 } 3173 splx(s); 3174 3175 return (rtval); 3176} 3177 3178/* 3179 * Clear the modify bits on the specified physical page. 3180 */ 3181void 3182pmap_clear_modify(vm_page_t m) 3183{ 3184 pmap_changebit(m, PG_M, FALSE); 3185} 3186 3187/* 3188 * pmap_clear_reference: 3189 * 3190 * Clear the reference bit on the specified physical page. 3191 */ 3192void 3193pmap_clear_reference(vm_page_t m) 3194{ 3195 pmap_changebit(m, PG_A, FALSE); 3196} 3197 3198/* 3199 * Miscellaneous support routines follow 3200 */ 3201 3202static void 3203i386_protection_init() 3204{ 3205 register int *kp, prot; 3206 3207 kp = protection_codes; 3208 for (prot = 0; prot < 8; prot++) { 3209 switch (prot) { 3210 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3211 /* 3212 * Read access is also 0. There isn't any execute bit, 3213 * so just make it readable. 3214 */ 3215 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3216 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3217 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3218 *kp++ = 0; 3219 break; 3220 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3221 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3222 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3223 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3224 *kp++ = PG_RW; 3225 break; 3226 } 3227 } 3228} 3229 3230/* 3231 * Map a set of physical memory pages into the kernel virtual 3232 * address space. Return a pointer to where it is mapped. This 3233 * routine is intended to be used for mapping device memory, 3234 * NOT real memory. 3235 */ 3236void * 3237pmap_mapdev(pa, size) 3238 vm_offset_t pa; 3239 vm_size_t size; 3240{ 3241 vm_offset_t va, tmpva, offset; 3242 3243 offset = pa & PAGE_MASK; 3244 size = roundup(offset + size, PAGE_SIZE); 3245 3246 GIANT_REQUIRED; 3247 3248 va = kmem_alloc_pageable(kernel_map, size); 3249 if (!va) 3250 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3251 3252 pa = pa & PG_FRAME; 3253 for (tmpva = va; size > 0; ) { 3254 pmap_kenter(tmpva, pa); 3255 size -= PAGE_SIZE; 3256 tmpva += PAGE_SIZE; 3257 pa += PAGE_SIZE; 3258 } 3259 pmap_invalidate_range(kernel_pmap, va, tmpva); 3260 return ((void *)(va + offset)); 3261} 3262 3263void 3264pmap_unmapdev(va, size) 3265 vm_offset_t va; 3266 vm_size_t size; 3267{ 3268 vm_offset_t base, offset, tmpva; 3269 pt_entry_t *pte; 3270 3271 base = va & PG_FRAME; 3272 offset = va & PAGE_MASK; 3273 size = roundup(offset + size, PAGE_SIZE); 3274 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE) { 3275 pte = vtopte(tmpva); 3276 *pte = 0; 3277 } 3278 pmap_invalidate_range(kernel_pmap, va, tmpva); 3279 kmem_free(kernel_map, base, size); 3280} 3281 3282/* 3283 * perform the pmap work for mincore 3284 */ 3285int 3286pmap_mincore(pmap, addr) 3287 pmap_t pmap; 3288 vm_offset_t addr; 3289{ 3290 pt_entry_t *ptep, pte; 3291 vm_page_t m; 3292 int val = 0; 3293 3294 ptep = pmap_pte(pmap, addr); 3295 if (ptep == 0) { 3296 return 0; 3297 } 3298 3299 if ((pte = *ptep) != 0) { 3300 vm_offset_t pa; 3301 3302 val = MINCORE_INCORE; 3303 if ((pte & PG_MANAGED) == 0) 3304 return val; 3305 3306 pa = pte & PG_FRAME; 3307 3308 m = PHYS_TO_VM_PAGE(pa); 3309 3310 /* 3311 * Modified by us 3312 */ 3313 if (pte & PG_M) 3314 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3315 else { 3316 /* 3317 * Modified by someone else 3318 */ 3319 vm_page_lock_queues(); 3320 if (m->dirty || pmap_is_modified(m)) 3321 val |= MINCORE_MODIFIED_OTHER; 3322 vm_page_unlock_queues(); 3323 } 3324 /* 3325 * Referenced by us 3326 */ 3327 if (pte & PG_A) 3328 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3329 else { 3330 /* 3331 * Referenced by someone else 3332 */ 3333 vm_page_lock_queues(); 3334 if ((m->flags & PG_REFERENCED) || 3335 pmap_ts_referenced(m)) { 3336 val |= MINCORE_REFERENCED_OTHER; 3337 vm_page_flag_set(m, PG_REFERENCED); 3338 } 3339 vm_page_unlock_queues(); 3340 } 3341 } 3342 return val; 3343} 3344 3345void 3346pmap_activate(struct thread *td) 3347{ 3348 struct proc *p = td->td_proc; 3349 pmap_t pmap; 3350 u_int32_t cr3; 3351 3352 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3353#if defined(SMP) 3354 pmap->pm_active |= PCPU_GET(cpumask); 3355#else 3356 pmap->pm_active |= 1; 3357#endif 3358 cr3 = vtophys(pmap->pm_pdir); 3359 /* XXXKSE this is wrong. 3360 * pmap_activate is for the current thread on the current cpu 3361 */ 3362 if (p->p_flag & P_KSES) { 3363 /* Make sure all other cr3 entries are updated. */ 3364 /* what if they are running? XXXKSE (maybe abort them) */ 3365 FOREACH_THREAD_IN_PROC(p, td) { 3366 td->td_pcb->pcb_cr3 = cr3; 3367 } 3368 } else { 3369 td->td_pcb->pcb_cr3 = cr3; 3370 } 3371 load_cr3(cr3); 3372#ifdef SWTCH_OPTIM_STATS 3373 tlb_flush_count++; 3374#endif 3375} 3376 3377vm_offset_t 3378pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3379{ 3380 3381 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3382 return addr; 3383 } 3384 3385 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3386 return addr; 3387} 3388 3389 3390#if defined(PMAP_DEBUG) 3391pmap_pid_dump(int pid) 3392{ 3393 pmap_t pmap; 3394 struct proc *p; 3395 int npte = 0; 3396 int index; 3397 3398 sx_slock(&allproc_lock); 3399 LIST_FOREACH(p, &allproc, p_list) { 3400 if (p->p_pid != pid) 3401 continue; 3402 3403 if (p->p_vmspace) { 3404 int i,j; 3405 index = 0; 3406 pmap = vmspace_pmap(p->p_vmspace); 3407 for (i = 0; i < NPDEPG; i++) { 3408 pd_entry_t *pde; 3409 pt_entry_t *pte; 3410 vm_offset_t base = i << PDRSHIFT; 3411 3412 pde = &pmap->pm_pdir[i]; 3413 if (pde && pmap_pde_v(pde)) { 3414 for (j = 0; j < NPTEPG; j++) { 3415 vm_offset_t va = base + (j << PAGE_SHIFT); 3416 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3417 if (index) { 3418 index = 0; 3419 printf("\n"); 3420 } 3421 sx_sunlock(&allproc_lock); 3422 return npte; 3423 } 3424 pte = pmap_pte_quick(pmap, va); 3425 if (pte && pmap_pte_v(pte)) { 3426 pt_entry_t pa; 3427 vm_page_t m; 3428 pa = *pte; 3429 m = PHYS_TO_VM_PAGE(pa); 3430 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3431 va, pa, m->hold_count, m->wire_count, m->flags); 3432 npte++; 3433 index++; 3434 if (index >= 2) { 3435 index = 0; 3436 printf("\n"); 3437 } else { 3438 printf(" "); 3439 } 3440 } 3441 } 3442 } 3443 } 3444 } 3445 } 3446 sx_sunlock(&allproc_lock); 3447 return npte; 3448} 3449#endif 3450 3451#if defined(DEBUG) 3452 3453static void pads(pmap_t pm); 3454void pmap_pvdump(vm_offset_t pa); 3455 3456/* print address space of pmap*/ 3457static void 3458pads(pm) 3459 pmap_t pm; 3460{ 3461 int i, j; 3462 vm_offset_t va; 3463 pt_entry_t *ptep; 3464 3465 if (pm == kernel_pmap) 3466 return; 3467 for (i = 0; i < NPDEPG; i++) 3468 if (pm->pm_pdir[i]) 3469 for (j = 0; j < NPTEPG; j++) { 3470 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3471 if (pm == kernel_pmap && va < KERNBASE) 3472 continue; 3473 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3474 continue; 3475 ptep = pmap_pte_quick(pm, va); 3476 if (pmap_pte_v(ptep)) 3477 printf("%x:%x ", va, *ptep); 3478 }; 3479 3480} 3481 3482void 3483pmap_pvdump(pa) 3484 vm_offset_t pa; 3485{ 3486 pv_entry_t pv; 3487 vm_page_t m; 3488 3489 printf("pa %x", pa); 3490 m = PHYS_TO_VM_PAGE(pa); 3491 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3492 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3493 pads(pv->pv_pmap); 3494 } 3495 printf(" "); 3496} 3497#endif 3498