pmap.c revision 110480
1264790Sbapt/* 2264790Sbapt * Copyright (c) 1991 Regents of the University of California. 3264790Sbapt * All rights reserved. 4264790Sbapt * Copyright (c) 1994 John S. Dyson 5264790Sbapt * All rights reserved. 6264790Sbapt * Copyright (c) 1994 David Greenman 7264790Sbapt * All rights reserved. 8264790Sbapt * 9264790Sbapt * This code is derived from software contributed to Berkeley by 10264790Sbapt * the Systems Programming Group of the University of Utah Computer 11264790Sbapt * Science Department and William Jolitz of UUNET Technologies Inc. 12264790Sbapt * 13264790Sbapt * Redistribution and use in source and binary forms, with or without 14264790Sbapt * modification, are permitted provided that the following conditions 15264790Sbapt * are met: 16264790Sbapt * 1. Redistributions of source code must retain the above copyright 17264790Sbapt * notice, this list of conditions and the following disclaimer. 18264790Sbapt * 2. Redistributions in binary form must reproduce the above copyright 19264790Sbapt * notice, this list of conditions and the following disclaimer in the 20264790Sbapt * documentation and/or other materials provided with the distribution. 21264790Sbapt * 3. All advertising materials mentioning features or use of this software 22264790Sbapt * must display the following acknowledgement: 23264790Sbapt * This product includes software developed by the University of 24264790Sbapt * California, Berkeley and its contributors. 25264790Sbapt * 4. Neither the name of the University nor the names of its contributors 26264790Sbapt * may be used to endorse or promote products derived from this software 27264790Sbapt * without specific prior written permission. 28264790Sbapt * 29264790Sbapt * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 30264790Sbapt * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 31264790Sbapt * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 32264790Sbapt * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 33264790Sbapt * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 34264790Sbapt * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 35264790Sbapt * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 36264790Sbapt * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 37264790Sbapt * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 38264790Sbapt * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 39264790Sbapt * SUCH DAMAGE. 40264790Sbapt * 41264790Sbapt * from: @(#)pmap.c 7.7 (Berkeley) 5/12/91 42264790Sbapt * $FreeBSD: head/sys/i386/i386/pmap.c 110480 2003-02-07 01:52:06Z peter $ 43264790Sbapt */ 44264790Sbapt 45264790Sbapt/* 46264790Sbapt * Manages physical address maps. 47264790Sbapt * 48264790Sbapt * In addition to hardware address maps, this 49264790Sbapt * module is called upon to provide software-use-only 50264790Sbapt * maps which may or may not be stored in the same 51264790Sbapt * 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; 155 156vm_offset_t avail_start; /* PA of first available physical page */ 157vm_offset_t avail_end; /* PA of last available physical page */ 158vm_offset_t virtual_avail; /* VA of first avail page (after kernel bss) */ 159vm_offset_t virtual_end; /* VA of last avail page (end of kernel AS) */ 160static boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */ 161static int pgeflag; /* PG_G or-in */ 162static int pseflag; /* PG_PS or-in */ 163 164static vm_object_t kptobj; 165 166static int nkpt; 167vm_offset_t kernel_vm_end; 168extern u_int32_t KERNend; 169 170/* 171 * Data for the pv entry allocation mechanism 172 */ 173static uma_zone_t pvzone; 174static struct vm_object pvzone_obj; 175static int pv_entry_count = 0, pv_entry_max = 0, pv_entry_high_water = 0; 176int pmap_pagedaemon_waken; 177 178/* 179 * All those kernel PT submaps that BSD is so fond of 180 */ 181pt_entry_t *CMAP1 = 0; 182static pt_entry_t *CMAP2, *CMAP3, *ptmmap; 183caddr_t CADDR1 = 0, ptvmmap = 0; 184static caddr_t CADDR2, CADDR3; 185static pt_entry_t *msgbufmap; 186struct msgbuf *msgbufp = 0; 187 188/* 189 * Crashdump maps. 190 */ 191static pt_entry_t *pt_crashdumpmap; 192static caddr_t crashdumpmap; 193 194#ifdef SMP 195extern pt_entry_t *SMPpt; 196#endif 197static pt_entry_t *PMAP1 = 0; 198static pt_entry_t *PADDR1 = 0; 199 200static PMAP_INLINE void free_pv_entry(pv_entry_t pv); 201static pt_entry_t *get_ptbase(pmap_t pmap); 202static pv_entry_t get_pv_entry(void); 203static void i386_protection_init(void); 204static __inline void pmap_changebit(vm_page_t m, int bit, boolean_t setem); 205 206static vm_page_t pmap_enter_quick(pmap_t pmap, vm_offset_t va, 207 vm_page_t m, vm_page_t mpte); 208static int pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t sva); 209static void pmap_remove_page(struct pmap *pmap, vm_offset_t va); 210static int pmap_remove_entry(struct pmap *pmap, vm_page_t m, 211 vm_offset_t va); 212static void pmap_insert_entry(pmap_t pmap, vm_offset_t va, 213 vm_page_t mpte, vm_page_t m); 214 215static vm_page_t pmap_allocpte(pmap_t pmap, vm_offset_t va); 216 217static int pmap_release_free_page(pmap_t pmap, vm_page_t p); 218static vm_page_t _pmap_allocpte(pmap_t pmap, unsigned ptepindex); 219static pt_entry_t *pmap_pte_quick(pmap_t pmap, vm_offset_t va); 220static vm_page_t pmap_page_lookup(vm_object_t object, vm_pindex_t pindex); 221static int pmap_unuse_pt(pmap_t, vm_offset_t, vm_page_t); 222static vm_offset_t pmap_kmem_choose(vm_offset_t addr); 223static void *pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait); 224 225static pd_entry_t pdir4mb; 226 227/* 228 * Routine: pmap_pte 229 * Function: 230 * Extract the page table entry associated 231 * with the given map/virtual_address pair. 232 */ 233 234PMAP_INLINE pt_entry_t * 235pmap_pte(pmap, va) 236 register pmap_t pmap; 237 vm_offset_t va; 238{ 239 pd_entry_t *pdeaddr; 240 241 if (pmap) { 242 pdeaddr = pmap_pde(pmap, va); 243 if (*pdeaddr & PG_PS) 244 return pdeaddr; 245 if (*pdeaddr) { 246 return get_ptbase(pmap) + i386_btop(va); 247 } 248 } 249 return (0); 250} 251 252/* 253 * Move the kernel virtual free pointer to the next 254 * 4MB. This is used to help improve performance 255 * by using a large (4MB) page for much of the kernel 256 * (.text, .data, .bss) 257 */ 258static vm_offset_t 259pmap_kmem_choose(vm_offset_t addr) 260{ 261 vm_offset_t newaddr = addr; 262 263#ifndef DISABLE_PSE 264 if (cpu_feature & CPUID_PSE) 265 newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 266#endif 267 return newaddr; 268} 269 270/* 271 * Bootstrap the system enough to run with virtual memory. 272 * 273 * On the i386 this is called after mapping has already been enabled 274 * and just syncs the pmap module with what has already been done. 275 * [We can't call it easily with mapping off since the kernel is not 276 * mapped with PA == VA, hence we would have to relocate every address 277 * from the linked base (virtual) address "KERNBASE" to the actual 278 * (physical) address starting relative to 0] 279 */ 280void 281pmap_bootstrap(firstaddr, loadaddr) 282 vm_offset_t firstaddr; 283 vm_offset_t loadaddr; 284{ 285 vm_offset_t va; 286 pt_entry_t *pte; 287 int i; 288 289 avail_start = firstaddr; 290 291 /* 292 * XXX The calculation of virtual_avail is wrong. It's NKPT*PAGE_SIZE too 293 * large. It should instead be correctly calculated in locore.s and 294 * not based on 'first' (which is a physical address, not a virtual 295 * address, for the start of unused physical memory). The kernel 296 * page tables are NOT double mapped and thus should not be included 297 * in this calculation. 298 */ 299 virtual_avail = (vm_offset_t) KERNBASE + firstaddr; 300 virtual_avail = pmap_kmem_choose(virtual_avail); 301 302 virtual_end = VM_MAX_KERNEL_ADDRESS; 303 304 /* 305 * Initialize protection array. 306 */ 307 i386_protection_init(); 308 309 /* 310 * Initialize the kernel pmap (which is statically allocated). 311 */ 312 kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD); 313 kernel_pmap->pm_active = -1; /* don't allow deactivation */ 314 TAILQ_INIT(&kernel_pmap->pm_pvlist); 315 LIST_INIT(&allpmaps); 316 LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list); 317 nkpt = NKPT; 318 319 /* 320 * Reserve some special page table entries/VA space for temporary 321 * mapping of pages. 322 */ 323#define SYSMAP(c, p, v, n) \ 324 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n); 325 326 va = virtual_avail; 327 pte = (pt_entry_t *) pmap_pte(kernel_pmap, va); 328 329 /* 330 * CMAP1/CMAP2 are used for zeroing and copying pages. 331 * CMAP3 is used for the idle process page zeroing. 332 */ 333 SYSMAP(caddr_t, CMAP1, CADDR1, 1) 334 SYSMAP(caddr_t, CMAP2, CADDR2, 1) 335 SYSMAP(caddr_t, CMAP3, CADDR3, 1) 336 337 /* 338 * Crashdump maps. 339 */ 340 SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS); 341 342 /* 343 * ptvmmap is used for reading arbitrary physical pages via /dev/mem. 344 * XXX ptmmap is not used. 345 */ 346 SYSMAP(caddr_t, ptmmap, ptvmmap, 1) 347 348 /* 349 * msgbufp is used to map the system message buffer. 350 * XXX msgbufmap is not used. 351 */ 352 SYSMAP(struct msgbuf *, msgbufmap, msgbufp, 353 atop(round_page(MSGBUF_SIZE))) 354 355 /* 356 * ptemap is used for pmap_pte_quick 357 */ 358 SYSMAP(pt_entry_t *, PMAP1, PADDR1, 1); 359 360 virtual_avail = va; 361 362 *CMAP1 = *CMAP2 = 0; 363 for (i = 0; i < NKPT; i++) 364 PTD[i] = 0; 365 366 pgeflag = 0; 367#ifndef DISABLE_PG_G 368 if (cpu_feature & CPUID_PGE) 369 pgeflag = PG_G; 370#endif 371 372/* 373 * Initialize the 4MB page size flag 374 */ 375 pseflag = 0; 376/* 377 * The 4MB page version of the initial 378 * kernel page mapping. 379 */ 380 pdir4mb = 0; 381 382#ifndef DISABLE_PSE 383 if (cpu_feature & CPUID_PSE) { 384 pd_entry_t ptditmp; 385 /* 386 * Note that we have enabled PSE mode 387 */ 388 pseflag = PG_PS; 389 ptditmp = *(PTmap + i386_btop(KERNBASE)); 390 ptditmp &= ~(NBPDR - 1); 391 ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag; 392 pdir4mb = ptditmp; 393 } 394#endif 395#ifndef SMP 396 /* 397 * Turn on PGE/PSE. SMP does this later on since the 398 * 4K page tables are required for AP boot (for now). 399 * XXX fixme. 400 */ 401 pmap_set_opt(); 402#endif 403#ifdef SMP 404 if (cpu_apic_address == 0) 405 panic("pmap_bootstrap: no local apic! (non-SMP hardware?)"); 406 407 /* local apic is mapped on last page */ 408 SMPpt[NPTEPG - 1] = (pt_entry_t)(PG_V | PG_RW | PG_N | pgeflag | 409 (cpu_apic_address & PG_FRAME)); 410#endif 411 invltlb(); 412} 413 414/* 415 * Enable 4MB page mode for MP startup. Turn on PG_G support. 416 * BSP will run this after all the AP's have started up. 417 */ 418void 419pmap_set_opt(void) 420{ 421 pt_entry_t *pte; 422 vm_offset_t va, endva; 423 424 if (pgeflag && (cpu_feature & CPUID_PGE)) { 425 load_cr4(rcr4() | CR4_PGE); 426 invltlb(); /* Insurance */ 427 } 428#ifndef DISABLE_PSE 429 if (pseflag && (cpu_feature & CPUID_PSE)) { 430 load_cr4(rcr4() | CR4_PSE); 431 invltlb(); /* Insurance */ 432 } 433#endif 434 if (PCPU_GET(cpuid) == 0) { 435#ifndef DISABLE_PSE 436 if (pdir4mb) { 437 kernel_pmap->pm_pdir[KPTDI] = PTD[KPTDI] = pdir4mb; 438 invltlb(); /* Insurance */ 439 } 440#endif 441 if (pgeflag) { 442 /* Turn on PG_G for text, data, bss pages. */ 443 va = (vm_offset_t)btext; 444#ifndef DISABLE_PSE 445 if (pseflag && (cpu_feature & CPUID_PSE)) { 446 if (va < KERNBASE + (1 << PDRSHIFT)) 447 va = KERNBASE + (1 << PDRSHIFT); 448 } 449#endif 450 endva = KERNBASE + KERNend; 451 while (va < endva) { 452 pte = vtopte(va); 453 if (*pte) 454 *pte |= pgeflag; 455 va += PAGE_SIZE; 456 } 457 invltlb(); /* Insurance */ 458 } 459 /* 460 * We do not need to broadcast the invltlb here, because 461 * each AP does it the moment it is released from the boot 462 * lock. See ap_init(). 463 */ 464 } 465} 466 467static void * 468pmap_allocf(uma_zone_t zone, int bytes, u_int8_t *flags, int wait) 469{ 470 *flags = UMA_SLAB_PRIV; 471 return (void *)kmem_alloc(kernel_map, bytes); 472} 473 474/* 475 * Initialize the pmap module. 476 * Called by vm_init, to initialize any structures that the pmap 477 * system needs to map virtual memory. 478 * pmap_init has been enhanced to support in a fairly consistant 479 * way, discontiguous physical memory. 480 */ 481void 482pmap_init(phys_start, phys_end) 483 vm_offset_t phys_start, phys_end; 484{ 485 int i; 486 int initial_pvs; 487 488 /* 489 * object for kernel page table pages 490 */ 491 kptobj = vm_object_allocate(OBJT_DEFAULT, NKPDE); 492 493 /* 494 * Allocate memory for random pmap data structures. Includes the 495 * pv_head_table. 496 */ 497 498 for(i = 0; i < vm_page_array_size; i++) { 499 vm_page_t m; 500 501 m = &vm_page_array[i]; 502 TAILQ_INIT(&m->md.pv_list); 503 m->md.pv_list_count = 0; 504 } 505 506 /* 507 * init the pv free list 508 */ 509 initial_pvs = vm_page_array_size; 510 if (initial_pvs < MINPV) 511 initial_pvs = MINPV; 512 pvzone = uma_zcreate("PV ENTRY", sizeof (struct pv_entry), NULL, NULL, 513 NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM); 514 uma_zone_set_allocf(pvzone, pmap_allocf); 515 uma_prealloc(pvzone, initial_pvs); 516 517 /* 518 * Now it is safe to enable pv_table recording. 519 */ 520 pmap_initialized = TRUE; 521} 522 523/* 524 * Initialize the address space (zone) for the pv_entries. Set a 525 * high water mark so that the system can recover from excessive 526 * numbers of pv entries. 527 */ 528void 529pmap_init2() 530{ 531 int shpgperproc = PMAP_SHPGPERPROC; 532 533 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc); 534 pv_entry_max = shpgperproc * maxproc + vm_page_array_size; 535 TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max); 536 pv_entry_high_water = 9 * (pv_entry_max / 10); 537 uma_zone_set_obj(pvzone, &pvzone_obj, pv_entry_max); 538} 539 540 541/*************************************************** 542 * Low level helper routines..... 543 ***************************************************/ 544 545#if defined(PMAP_DIAGNOSTIC) 546 547/* 548 * This code checks for non-writeable/modified pages. 549 * This should be an invalid condition. 550 */ 551static int 552pmap_nw_modified(pt_entry_t ptea) 553{ 554 int pte; 555 556 pte = (int) ptea; 557 558 if ((pte & (PG_M|PG_RW)) == PG_M) 559 return 1; 560 else 561 return 0; 562} 563#endif 564 565 566/* 567 * this routine defines the region(s) of memory that should 568 * not be tested for the modified bit. 569 */ 570static PMAP_INLINE int 571pmap_track_modified(vm_offset_t va) 572{ 573 if ((va < kmi.clean_sva) || (va >= kmi.clean_eva)) 574 return 1; 575 else 576 return 0; 577} 578 579#ifdef I386_CPU 580/* 581 * i386 only has "invalidate everything" and no SMP to worry about. 582 */ 583PMAP_INLINE void 584pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 585{ 586 587 if (pmap == kernel_pmap || pmap->pm_active) 588 invltlb(); 589} 590 591PMAP_INLINE void 592pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 593{ 594 595 if (pmap == kernel_pmap || pmap->pm_active) 596 invltlb(); 597} 598 599PMAP_INLINE void 600pmap_invalidate_all(pmap_t pmap) 601{ 602 603 if (pmap == kernel_pmap || pmap->pm_active) 604 invltlb(); 605} 606#else /* !I386_CPU */ 607#ifdef SMP 608/* 609 * For SMP, these functions have to use the IPI mechanism for coherence. 610 */ 611void 612pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 613{ 614 u_int cpumask; 615 u_int other_cpus; 616 617 critical_enter(); 618 /* 619 * We need to disable interrupt preemption but MUST NOT have 620 * interrupts disabled here. 621 * XXX we may need to hold schedlock to get a coherent pm_active 622 */ 623 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 624 invlpg(va); 625 smp_invlpg(va); 626 } else { 627 cpumask = PCPU_GET(cpumask); 628 other_cpus = PCPU_GET(other_cpus); 629 if (pmap->pm_active & cpumask) 630 invlpg(va); 631 if (pmap->pm_active & other_cpus) 632 smp_masked_invlpg(pmap->pm_active & other_cpus, va); 633 } 634 critical_exit(); 635} 636 637void 638pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 639{ 640 u_int cpumask; 641 u_int other_cpus; 642 vm_offset_t addr; 643 644 critical_enter(); 645 /* 646 * We need to disable interrupt preemption but MUST NOT have 647 * interrupts disabled here. 648 * XXX we may need to hold schedlock to get a coherent pm_active 649 */ 650 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 651 for (addr = sva; addr < eva; addr += PAGE_SIZE) 652 invlpg(addr); 653 smp_invlpg_range(sva, eva); 654 } else { 655 cpumask = PCPU_GET(cpumask); 656 other_cpus = PCPU_GET(other_cpus); 657 if (pmap->pm_active & cpumask) 658 for (addr = sva; addr < eva; addr += PAGE_SIZE) 659 invlpg(addr); 660 if (pmap->pm_active & other_cpus) 661 smp_masked_invlpg_range(pmap->pm_active & other_cpus, 662 sva, eva); 663 } 664 critical_exit(); 665} 666 667void 668pmap_invalidate_all(pmap_t pmap) 669{ 670 u_int cpumask; 671 u_int other_cpus; 672 673#ifdef SWTCH_OPTIM_STATS 674 tlb_flush_count++; 675#endif 676 critical_enter(); 677 /* 678 * We need to disable interrupt preemption but MUST NOT have 679 * interrupts disabled here. 680 * XXX we may need to hold schedlock to get a coherent pm_active 681 */ 682 if (pmap->pm_active == -1 || pmap->pm_active == all_cpus) { 683 invltlb(); 684 smp_invltlb(); 685 } else { 686 cpumask = PCPU_GET(cpumask); 687 other_cpus = PCPU_GET(other_cpus); 688 if (pmap->pm_active & cpumask) 689 invltlb(); 690 if (pmap->pm_active & other_cpus) 691 smp_masked_invltlb(pmap->pm_active & other_cpus); 692 } 693 critical_exit(); 694} 695#else /* !SMP */ 696/* 697 * Normal, non-SMP, 486+ invalidation functions. 698 * We inline these within pmap.c for speed. 699 */ 700PMAP_INLINE void 701pmap_invalidate_page(pmap_t pmap, vm_offset_t va) 702{ 703 704 if (pmap == kernel_pmap || pmap->pm_active) 705 invlpg(va); 706} 707 708PMAP_INLINE void 709pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 710{ 711 vm_offset_t addr; 712 713 if (pmap == kernel_pmap || pmap->pm_active) 714 for (addr = sva; addr < eva; addr += PAGE_SIZE) 715 invlpg(addr); 716} 717 718PMAP_INLINE void 719pmap_invalidate_all(pmap_t pmap) 720{ 721 722 if (pmap == kernel_pmap || pmap->pm_active) 723 invltlb(); 724} 725#endif /* !SMP */ 726#endif /* !I386_CPU */ 727 728/* 729 * Return an address which is the base of the Virtual mapping of 730 * all the PTEs for the given pmap. Note this doesn't say that 731 * all the PTEs will be present or that the pages there are valid. 732 * The PTEs are made available by the recursive mapping trick. 733 * It will map in the alternate PTE space if needed. 734 */ 735static pt_entry_t * 736get_ptbase(pmap) 737 pmap_t pmap; 738{ 739 pd_entry_t frame; 740 741 /* are we current address space or kernel? */ 742 if (pmap == kernel_pmap) 743 return PTmap; 744 frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 745 if (frame == (PTDpde & PG_FRAME)) 746 return PTmap; 747 /* otherwise, we are alternate address space */ 748 if (frame != (APTDpde & PG_FRAME)) { 749 APTDpde = (pd_entry_t) (frame | PG_RW | PG_V); 750 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 751 } 752 return APTmap; 753} 754 755/* 756 * Super fast pmap_pte routine best used when scanning 757 * the pv lists. This eliminates many coarse-grained 758 * invltlb calls. Note that many of the pv list 759 * scans are across different pmaps. It is very wasteful 760 * to do an entire invltlb for checking a single mapping. 761 */ 762 763static pt_entry_t * 764pmap_pte_quick(pmap, va) 765 register pmap_t pmap; 766 vm_offset_t va; 767{ 768 pd_entry_t pde, newpf; 769 pde = pmap->pm_pdir[va >> PDRSHIFT]; 770 if (pde != 0) { 771 pd_entry_t frame = pmap->pm_pdir[PTDPTDI] & PG_FRAME; 772 unsigned index = i386_btop(va); 773 /* are we current address space or kernel? */ 774 if (pmap == kernel_pmap || frame == (PTDpde & PG_FRAME)) 775 return PTmap + index; 776 newpf = pde & PG_FRAME; 777 if (((*PMAP1) & PG_FRAME) != newpf) { 778 *PMAP1 = newpf | PG_RW | PG_V; 779 pmap_invalidate_page(kernel_pmap, (vm_offset_t)PADDR1); 780 } 781 return PADDR1 + (index & (NPTEPG - 1)); 782 } 783 return (0); 784} 785 786/* 787 * Routine: pmap_extract 788 * Function: 789 * Extract the physical page address associated 790 * with the given map/virtual_address pair. 791 */ 792vm_offset_t 793pmap_extract(pmap, va) 794 register pmap_t pmap; 795 vm_offset_t va; 796{ 797 vm_offset_t rtval; /* XXX FIXME */ 798 vm_offset_t pdirindex; 799 800 if (pmap == 0) 801 return 0; 802 pdirindex = va >> PDRSHIFT; 803 rtval = pmap->pm_pdir[pdirindex]; 804 if (rtval != 0) { 805 pt_entry_t *pte; 806 if ((rtval & PG_PS) != 0) { 807 rtval &= ~(NBPDR - 1); 808 rtval |= va & (NBPDR - 1); 809 return rtval; 810 } 811 pte = get_ptbase(pmap) + i386_btop(va); 812 rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); 813 return rtval; 814 } 815 return 0; 816 817} 818 819/*************************************************** 820 * Low level mapping routines..... 821 ***************************************************/ 822 823/* 824 * Add a wired page to the kva. 825 * Note: not SMP coherent. 826 */ 827PMAP_INLINE void 828pmap_kenter(vm_offset_t va, vm_offset_t pa) 829{ 830 pt_entry_t *pte; 831 832 pte = vtopte(va); 833 *pte = pa | PG_RW | PG_V | pgeflag; 834} 835 836/* 837 * Remove a page from the kernel pagetables. 838 * Note: not SMP coherent. 839 */ 840PMAP_INLINE void 841pmap_kremove(vm_offset_t va) 842{ 843 pt_entry_t *pte; 844 845 pte = vtopte(va); 846 *pte = 0; 847} 848 849/* 850 * Used to map a range of physical addresses into kernel 851 * virtual address space. 852 * 853 * The value passed in '*virt' is a suggested virtual address for 854 * the mapping. Architectures which can support a direct-mapped 855 * physical to virtual region can return the appropriate address 856 * within that region, leaving '*virt' unchanged. Other 857 * architectures should map the pages starting at '*virt' and 858 * update '*virt' with the first usable address after the mapped 859 * region. 860 */ 861vm_offset_t 862pmap_map(vm_offset_t *virt, vm_offset_t start, vm_offset_t end, int prot) 863{ 864 vm_offset_t va, sva; 865 866 va = sva = *virt; 867 while (start < end) { 868 pmap_kenter(va, start); 869 va += PAGE_SIZE; 870 start += PAGE_SIZE; 871 } 872 pmap_invalidate_range(kernel_pmap, sva, va); 873 *virt = va; 874 return (sva); 875} 876 877 878/* 879 * Add a list of wired pages to the kva 880 * this routine is only used for temporary 881 * kernel mappings that do not need to have 882 * page modification or references recorded. 883 * Note that old mappings are simply written 884 * over. The page *must* be wired. 885 * Note: SMP coherent. Uses a ranged shootdown IPI. 886 */ 887void 888pmap_qenter(vm_offset_t sva, vm_page_t *m, int count) 889{ 890 vm_offset_t va; 891 892 va = sva; 893 while (count-- > 0) { 894 pmap_kenter(va, VM_PAGE_TO_PHYS(*m)); 895 va += PAGE_SIZE; 896 m++; 897 } 898 pmap_invalidate_range(kernel_pmap, sva, va); 899} 900 901/* 902 * This routine tears out page mappings from the 903 * kernel -- it is meant only for temporary mappings. 904 * Note: SMP coherent. Uses a ranged shootdown IPI. 905 */ 906void 907pmap_qremove(vm_offset_t sva, int count) 908{ 909 vm_offset_t va; 910 911 va = sva; 912 while (count-- > 0) { 913 pmap_kremove(va); 914 va += PAGE_SIZE; 915 } 916 pmap_invalidate_range(kernel_pmap, sva, va); 917} 918 919static vm_page_t 920pmap_page_lookup(vm_object_t object, vm_pindex_t pindex) 921{ 922 vm_page_t m; 923 924retry: 925 m = vm_page_lookup(object, pindex); 926 if (m != NULL) { 927 vm_page_lock_queues(); 928 if (vm_page_sleep_if_busy(m, FALSE, "pplookp")) 929 goto retry; 930 vm_page_unlock_queues(); 931 } 932 return m; 933} 934 935#ifndef KSTACK_MAX_PAGES 936#define KSTACK_MAX_PAGES 32 937#endif 938 939/* 940 * Create the kernel stack (including pcb for i386) for a new thread. 941 * This routine directly affects the fork perf for a process and 942 * create performance for a thread. 943 */ 944void 945pmap_new_thread(struct thread *td, int pages) 946{ 947 int i; 948 vm_page_t ma[KSTACK_MAX_PAGES]; 949 vm_object_t ksobj; 950 vm_page_t m; 951 vm_offset_t ks; 952 953 /* Bounds check */ 954 if (pages <= 1) 955 pages = KSTACK_PAGES; 956 else if (pages > KSTACK_MAX_PAGES) 957 pages = KSTACK_MAX_PAGES; 958 959 /* 960 * allocate object for the kstack 961 */ 962 ksobj = vm_object_allocate(OBJT_DEFAULT, pages); 963 td->td_kstack_obj = ksobj; 964 965 /* get a kernel virtual address for the kstack for this thread */ 966#ifdef KSTACK_GUARD 967 ks = kmem_alloc_nofault(kernel_map, (pages + 1) * PAGE_SIZE); 968 if (ks == 0) 969 panic("pmap_new_thread: kstack allocation failed"); 970 if (*vtopte(ks) != 0) 971 pmap_qremove(ks, 1); 972 ks += PAGE_SIZE; 973 td->td_kstack = ks; 974#else 975 /* get a kernel virtual address for the kstack for this thread */ 976 ks = kmem_alloc_nofault(kernel_map, pages * PAGE_SIZE); 977 if (ks == 0) 978 panic("pmap_new_thread: kstack allocation failed"); 979 td->td_kstack = ks; 980#endif 981 /* 982 * Knowing the number of pages allocated is useful when you 983 * want to deallocate them. 984 */ 985 td->td_kstack_pages = pages; 986 987 /* 988 * For the length of the stack, link in a real page of ram for each 989 * page of stack. 990 */ 991 for (i = 0; i < pages; i++) { 992 /* 993 * Get a kernel stack page 994 */ 995 m = vm_page_grab(ksobj, i, 996 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED); 997 ma[i] = m; 998 999 vm_page_lock_queues(); 1000 vm_page_wakeup(m); 1001 vm_page_flag_clear(m, PG_ZERO); 1002 m->valid = VM_PAGE_BITS_ALL; 1003 vm_page_unlock_queues(); 1004 } 1005 pmap_qenter(ks, ma, pages); 1006} 1007 1008/* 1009 * Dispose the kernel stack for a thread that has exited. 1010 * This routine directly impacts the exit perf of a process and thread. 1011 */ 1012void 1013pmap_dispose_thread(td) 1014 struct thread *td; 1015{ 1016 int i; 1017 int pages; 1018 vm_object_t ksobj; 1019 vm_offset_t ks; 1020 vm_page_t m; 1021 1022 pages = td->td_kstack_pages; 1023 ksobj = td->td_kstack_obj; 1024 ks = td->td_kstack; 1025 pmap_qremove(ks, pages); 1026 for (i = 0; i < pages; i++) { 1027 m = vm_page_lookup(ksobj, i); 1028 if (m == NULL) 1029 panic("pmap_dispose_thread: kstack already missing?"); 1030 vm_page_lock_queues(); 1031 vm_page_busy(m); 1032 vm_page_unwire(m, 0); 1033 vm_page_free(m); 1034 vm_page_unlock_queues(); 1035 } 1036 /* 1037 * Free the space that this stack was mapped to in the kernel 1038 * address map. 1039 */ 1040#ifdef KSTACK_GUARD 1041 kmem_free(kernel_map, ks - PAGE_SIZE, (pages + 1) * PAGE_SIZE); 1042#else 1043 kmem_free(kernel_map, ks, pages * PAGE_SIZE); 1044#endif 1045 vm_object_deallocate(ksobj); 1046} 1047 1048/* 1049 * Set up a variable sized alternate kstack. Though it may look MI, it may 1050 * need to be different on certain arches like ia64. 1051 */ 1052void 1053pmap_new_altkstack(struct thread *td, int pages) 1054{ 1055 /* shuffle the original stack */ 1056 td->td_altkstack_obj = td->td_kstack_obj; 1057 td->td_altkstack = td->td_kstack; 1058 td->td_altkstack_pages = td->td_kstack_pages; 1059 1060 pmap_new_thread(td, pages); 1061} 1062 1063void 1064pmap_dispose_altkstack(td) 1065 struct thread *td; 1066{ 1067 pmap_dispose_thread(td); 1068 1069 /* restore the original kstack */ 1070 td->td_kstack = td->td_altkstack; 1071 td->td_kstack_obj = td->td_altkstack_obj; 1072 td->td_kstack_pages = td->td_altkstack_pages; 1073 td->td_altkstack = 0; 1074 td->td_altkstack_obj = NULL; 1075 td->td_altkstack_pages = 0; 1076} 1077 1078/* 1079 * Allow the Kernel stack for a thread to be prejudicially paged out. 1080 */ 1081void 1082pmap_swapout_thread(td) 1083 struct thread *td; 1084{ 1085 int i; 1086 int pages; 1087 vm_object_t ksobj; 1088 vm_offset_t ks; 1089 vm_page_t m; 1090 1091 pages = td->td_kstack_pages; 1092 ksobj = td->td_kstack_obj; 1093 ks = td->td_kstack; 1094 pmap_qremove(ks, pages); 1095 for (i = 0; i < pages; i++) { 1096 m = vm_page_lookup(ksobj, i); 1097 if (m == NULL) 1098 panic("pmap_swapout_thread: kstack already missing?"); 1099 vm_page_lock_queues(); 1100 vm_page_dirty(m); 1101 vm_page_unwire(m, 0); 1102 vm_page_unlock_queues(); 1103 } 1104} 1105 1106/* 1107 * Bring the kernel stack for a specified thread back in. 1108 */ 1109void 1110pmap_swapin_thread(td) 1111 struct thread *td; 1112{ 1113 int i, rv; 1114 int pages; 1115 vm_page_t ma[KSTACK_MAX_PAGES]; 1116 vm_object_t ksobj; 1117 vm_offset_t ks; 1118 vm_page_t m; 1119 1120 pages = td->td_kstack_pages; 1121 ksobj = td->td_kstack_obj; 1122 ks = td->td_kstack; 1123 for (i = 0; i < pages; i++) { 1124 m = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1125 if (m->valid != VM_PAGE_BITS_ALL) { 1126 rv = vm_pager_get_pages(ksobj, &m, 1, 0); 1127 if (rv != VM_PAGER_OK) 1128 panic("pmap_swapin_thread: cannot get kstack for proc: %d\n", td->td_proc->p_pid); 1129 m = vm_page_lookup(ksobj, i); 1130 m->valid = VM_PAGE_BITS_ALL; 1131 } 1132 ma[i] = m; 1133 vm_page_lock_queues(); 1134 vm_page_wire(m); 1135 vm_page_wakeup(m); 1136 vm_page_unlock_queues(); 1137 } 1138 pmap_qenter(ks, ma, pages); 1139} 1140 1141/*************************************************** 1142 * Page table page management routines..... 1143 ***************************************************/ 1144 1145/* 1146 * This routine unholds page table pages, and if the hold count 1147 * drops to zero, then it decrements the wire count. 1148 */ 1149static int 1150_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1151{ 1152 1153 while (vm_page_sleep_if_busy(m, FALSE, "pmuwpt")) 1154 vm_page_lock_queues(); 1155 1156 if (m->hold_count == 0) { 1157 vm_offset_t pteva; 1158 /* 1159 * unmap the page table page 1160 */ 1161 pmap->pm_pdir[m->pindex] = 0; 1162 --pmap->pm_stats.resident_count; 1163 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1164 (PTDpde & PG_FRAME)) { 1165 /* 1166 * Do an invltlb to make the invalidated mapping 1167 * take effect immediately. 1168 */ 1169 pteva = VM_MAXUSER_ADDRESS + i386_ptob(m->pindex); 1170 pmap_invalidate_page(pmap, pteva); 1171 } 1172 1173 if (pmap->pm_ptphint == m) 1174 pmap->pm_ptphint = NULL; 1175 1176 /* 1177 * If the page is finally unwired, simply free it. 1178 */ 1179 --m->wire_count; 1180 if (m->wire_count == 0) { 1181 vm_page_busy(m); 1182 vm_page_free_zero(m); 1183 atomic_subtract_int(&cnt.v_wire_count, 1); 1184 } 1185 return 1; 1186 } 1187 return 0; 1188} 1189 1190static PMAP_INLINE int 1191pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1192{ 1193 vm_page_unhold(m); 1194 if (m->hold_count == 0) 1195 return _pmap_unwire_pte_hold(pmap, m); 1196 else 1197 return 0; 1198} 1199 1200/* 1201 * After removing a page table entry, this routine is used to 1202 * conditionally free the page, and manage the hold/wire counts. 1203 */ 1204static int 1205pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1206{ 1207 unsigned ptepindex; 1208 if (va >= VM_MAXUSER_ADDRESS) 1209 return 0; 1210 1211 if (mpte == NULL) { 1212 ptepindex = (va >> PDRSHIFT); 1213 if (pmap->pm_ptphint && 1214 (pmap->pm_ptphint->pindex == ptepindex)) { 1215 mpte = pmap->pm_ptphint; 1216 } else { 1217 while ((mpte = vm_page_lookup(pmap->pm_pteobj, ptepindex)) != NULL && 1218 vm_page_sleep_if_busy(mpte, FALSE, "pulook")) 1219 vm_page_lock_queues(); 1220 pmap->pm_ptphint = mpte; 1221 } 1222 } 1223 1224 return pmap_unwire_pte_hold(pmap, mpte); 1225} 1226 1227void 1228pmap_pinit0(pmap) 1229 struct pmap *pmap; 1230{ 1231 pmap->pm_pdir = 1232 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1233 pmap_kenter((vm_offset_t)pmap->pm_pdir, (vm_offset_t)IdlePTD); 1234#ifndef I386_CPU 1235 invlpg((vm_offset_t)pmap->pm_pdir); 1236#else 1237 invltlb(); 1238#endif 1239 pmap->pm_ptphint = NULL; 1240 pmap->pm_active = 0; 1241 TAILQ_INIT(&pmap->pm_pvlist); 1242 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1243 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1244} 1245 1246/* 1247 * Initialize a preallocated and zeroed pmap structure, 1248 * such as one in a vmspace structure. 1249 */ 1250void 1251pmap_pinit(pmap) 1252 register struct pmap *pmap; 1253{ 1254 vm_page_t ptdpg; 1255 1256 /* 1257 * No need to allocate page table space yet but we do need a valid 1258 * page directory table. 1259 */ 1260 if (pmap->pm_pdir == NULL) 1261 pmap->pm_pdir = 1262 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1263 1264 /* 1265 * allocate object for the ptes 1266 */ 1267 if (pmap->pm_pteobj == NULL) 1268 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, PTDPTDI + 1); 1269 1270 /* 1271 * allocate the page directory page 1272 */ 1273 ptdpg = vm_page_grab(pmap->pm_pteobj, PTDPTDI, 1274 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | VM_ALLOC_WIRED | VM_ALLOC_ZERO); 1275 vm_page_lock_queues(); 1276 vm_page_flag_clear(ptdpg, PG_BUSY); 1277 ptdpg->valid = VM_PAGE_BITS_ALL; 1278 vm_page_unlock_queues(); 1279 1280 pmap_qenter((vm_offset_t) pmap->pm_pdir, &ptdpg, 1); 1281 if ((ptdpg->flags & PG_ZERO) == 0) 1282 bzero(pmap->pm_pdir, PAGE_SIZE); 1283 1284 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1285 /* Wire in kernel global address entries. */ 1286 /* XXX copies current process, does not fill in MPPTDI */ 1287 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1288#ifdef SMP 1289 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1290#endif 1291 1292 /* install self-referential address mapping entry */ 1293 pmap->pm_pdir[PTDPTDI] = 1294 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1295 1296 pmap->pm_active = 0; 1297 pmap->pm_ptphint = NULL; 1298 TAILQ_INIT(&pmap->pm_pvlist); 1299 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1300} 1301 1302/* 1303 * Wire in kernel global address entries. To avoid a race condition 1304 * between pmap initialization and pmap_growkernel, this procedure 1305 * should be called after the vmspace is attached to the process 1306 * but before this pmap is activated. 1307 */ 1308void 1309pmap_pinit2(pmap) 1310 struct pmap *pmap; 1311{ 1312 /* XXX: Remove this stub when no longer called */ 1313} 1314 1315static int 1316pmap_release_free_page(pmap_t pmap, vm_page_t p) 1317{ 1318 pd_entry_t *pde = pmap->pm_pdir; 1319 1320 /* 1321 * This code optimizes the case of freeing non-busy 1322 * page-table pages. Those pages are zero now, and 1323 * might as well be placed directly into the zero queue. 1324 */ 1325 vm_page_lock_queues(); 1326 if (vm_page_sleep_if_busy(p, FALSE, "pmaprl")) 1327 return (0); 1328 vm_page_busy(p); 1329 1330 /* 1331 * Remove the page table page from the processes address space. 1332 */ 1333 pde[p->pindex] = 0; 1334 pmap->pm_stats.resident_count--; 1335 1336 if (p->hold_count) { 1337 panic("pmap_release: freeing held page table page"); 1338 } 1339 /* 1340 * Page directory pages need to have the kernel 1341 * stuff cleared, so they can go into the zero queue also. 1342 */ 1343 if (p->pindex == PTDPTDI) { 1344 bzero(pde + KPTDI, nkpt * PTESIZE); 1345#ifdef SMP 1346 pde[MPPTDI] = 0; 1347#endif 1348 pde[APTDPTDI] = 0; 1349 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1350 } 1351 1352 if (pmap->pm_ptphint == p) 1353 pmap->pm_ptphint = NULL; 1354 1355 p->wire_count--; 1356 atomic_subtract_int(&cnt.v_wire_count, 1); 1357 vm_page_free_zero(p); 1358 vm_page_unlock_queues(); 1359 return 1; 1360} 1361 1362/* 1363 * this routine is called if the page table page is not 1364 * mapped correctly. 1365 */ 1366static vm_page_t 1367_pmap_allocpte(pmap, ptepindex) 1368 pmap_t pmap; 1369 unsigned ptepindex; 1370{ 1371 vm_offset_t pteva, ptepa; /* XXXPA */ 1372 vm_page_t m; 1373 1374 /* 1375 * Find or fabricate a new pagetable page 1376 */ 1377 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1378 VM_ALLOC_WIRED | VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1379 1380 KASSERT(m->queue == PQ_NONE, 1381 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1382 1383 /* 1384 * Increment the hold count for the page table page 1385 * (denoting a new mapping.) 1386 */ 1387 m->hold_count++; 1388 1389 /* 1390 * Map the pagetable page into the process address space, if 1391 * it isn't already there. 1392 */ 1393 1394 pmap->pm_stats.resident_count++; 1395 1396 ptepa = VM_PAGE_TO_PHYS(m); 1397 pmap->pm_pdir[ptepindex] = 1398 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1399 1400 /* 1401 * Set the page table hint 1402 */ 1403 pmap->pm_ptphint = m; 1404 1405 /* 1406 * Try to use the new mapping, but if we cannot, then 1407 * do it with the routine that maps the page explicitly. 1408 */ 1409 if ((m->flags & PG_ZERO) == 0) { 1410 if ((pmap->pm_pdir[PTDPTDI] & PG_FRAME) == 1411 (PTDpde & PG_FRAME)) { 1412 pteva = VM_MAXUSER_ADDRESS + i386_ptob(ptepindex); 1413 bzero((caddr_t) pteva, PAGE_SIZE); 1414 } else { 1415 pmap_zero_page(m); 1416 } 1417 } 1418 vm_page_lock_queues(); 1419 m->valid = VM_PAGE_BITS_ALL; 1420 vm_page_flag_clear(m, PG_ZERO); 1421 vm_page_wakeup(m); 1422 vm_page_unlock_queues(); 1423 1424 return m; 1425} 1426 1427static vm_page_t 1428pmap_allocpte(pmap_t pmap, vm_offset_t va) 1429{ 1430 unsigned ptepindex; 1431 pd_entry_t ptepa; 1432 vm_page_t m; 1433 1434 /* 1435 * Calculate pagetable page index 1436 */ 1437 ptepindex = va >> PDRSHIFT; 1438 1439 /* 1440 * Get the page directory entry 1441 */ 1442 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1443 1444 /* 1445 * This supports switching from a 4MB page to a 1446 * normal 4K page. 1447 */ 1448 if (ptepa & PG_PS) { 1449 pmap->pm_pdir[ptepindex] = 0; 1450 ptepa = 0; 1451 pmap_invalidate_all(kernel_pmap); 1452 } 1453 1454 /* 1455 * If the page table page is mapped, we just increment the 1456 * hold count, and activate it. 1457 */ 1458 if (ptepa) { 1459 /* 1460 * In order to get the page table page, try the 1461 * hint first. 1462 */ 1463 if (pmap->pm_ptphint && 1464 (pmap->pm_ptphint->pindex == ptepindex)) { 1465 m = pmap->pm_ptphint; 1466 } else { 1467 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1468 pmap->pm_ptphint = m; 1469 } 1470 m->hold_count++; 1471 return m; 1472 } 1473 /* 1474 * Here if the pte page isn't mapped, or if it has been deallocated. 1475 */ 1476 return _pmap_allocpte(pmap, ptepindex); 1477} 1478 1479 1480/*************************************************** 1481* Pmap allocation/deallocation routines. 1482 ***************************************************/ 1483 1484/* 1485 * Release any resources held by the given physical map. 1486 * Called when a pmap initialized by pmap_pinit is being released. 1487 * Should only be called if the map contains no valid mappings. 1488 */ 1489void 1490pmap_release(pmap_t pmap) 1491{ 1492 vm_page_t p,n,ptdpg; 1493 vm_object_t object = pmap->pm_pteobj; 1494 int curgeneration; 1495 1496#if defined(DIAGNOSTIC) 1497 if (object->ref_count != 1) 1498 panic("pmap_release: pteobj reference count != 1"); 1499#endif 1500 1501 ptdpg = NULL; 1502 LIST_REMOVE(pmap, pm_list); 1503retry: 1504 curgeneration = object->generation; 1505 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1506 n = TAILQ_NEXT(p, listq); 1507 if (p->pindex == PTDPTDI) { 1508 ptdpg = p; 1509 continue; 1510 } 1511 while (1) { 1512 if (!pmap_release_free_page(pmap, p) && 1513 (object->generation != curgeneration)) 1514 goto retry; 1515 } 1516 } 1517 1518 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1519 goto retry; 1520} 1521 1522static int 1523kvm_size(SYSCTL_HANDLER_ARGS) 1524{ 1525 unsigned long ksize = VM_MAX_KERNEL_ADDRESS - KERNBASE; 1526 1527 return sysctl_handle_long(oidp, &ksize, 0, req); 1528} 1529SYSCTL_PROC(_vm, OID_AUTO, kvm_size, CTLTYPE_LONG|CTLFLAG_RD, 1530 0, 0, kvm_size, "IU", "Size of KVM"); 1531 1532static int 1533kvm_free(SYSCTL_HANDLER_ARGS) 1534{ 1535 unsigned long kfree = VM_MAX_KERNEL_ADDRESS - kernel_vm_end; 1536 1537 return sysctl_handle_long(oidp, &kfree, 0, req); 1538} 1539SYSCTL_PROC(_vm, OID_AUTO, kvm_free, CTLTYPE_LONG|CTLFLAG_RD, 1540 0, 0, kvm_free, "IU", "Amount of KVM free"); 1541 1542/* 1543 * grow the number of kernel page table entries, if needed 1544 */ 1545void 1546pmap_growkernel(vm_offset_t addr) 1547{ 1548 struct pmap *pmap; 1549 int s; 1550 vm_offset_t ptppaddr; 1551 vm_page_t nkpg; 1552 pd_entry_t newpdir; 1553 1554 s = splhigh(); 1555 if (kernel_vm_end == 0) { 1556 kernel_vm_end = KERNBASE; 1557 nkpt = 0; 1558 while (pdir_pde(PTD, kernel_vm_end)) { 1559 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1560 nkpt++; 1561 } 1562 } 1563 addr = roundup2(addr, PAGE_SIZE * NPTEPG); 1564 while (kernel_vm_end < addr) { 1565 if (pdir_pde(PTD, kernel_vm_end)) { 1566 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1567 continue; 1568 } 1569 1570 /* 1571 * This index is bogus, but out of the way 1572 */ 1573 nkpg = vm_page_alloc(kptobj, nkpt, 1574 VM_ALLOC_SYSTEM | VM_ALLOC_WIRED); 1575 if (!nkpg) 1576 panic("pmap_growkernel: no memory to grow kernel"); 1577 1578 nkpt++; 1579 1580 pmap_zero_page(nkpg); 1581 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1582 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1583 pdir_pde(PTD, kernel_vm_end) = newpdir; 1584 1585 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1586 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1587 } 1588 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1589 } 1590 splx(s); 1591} 1592 1593 1594/*************************************************** 1595 * page management routines. 1596 ***************************************************/ 1597 1598/* 1599 * free the pv_entry back to the free list 1600 */ 1601static PMAP_INLINE void 1602free_pv_entry(pv_entry_t pv) 1603{ 1604 pv_entry_count--; 1605 uma_zfree(pvzone, pv); 1606} 1607 1608/* 1609 * get a new pv_entry, allocating a block from the system 1610 * when needed. 1611 * the memory allocation is performed bypassing the malloc code 1612 * because of the possibility of allocations at interrupt time. 1613 */ 1614static pv_entry_t 1615get_pv_entry(void) 1616{ 1617 pv_entry_count++; 1618 if (pv_entry_high_water && 1619 (pv_entry_count > pv_entry_high_water) && 1620 (pmap_pagedaemon_waken == 0)) { 1621 pmap_pagedaemon_waken = 1; 1622 wakeup (&vm_pages_needed); 1623 } 1624 return uma_zalloc(pvzone, M_NOWAIT); 1625} 1626 1627/* 1628 * If it is the first entry on the list, it is actually 1629 * in the header and we must copy the following entry up 1630 * to the header. Otherwise we must search the list for 1631 * the entry. In either case we free the now unused entry. 1632 */ 1633 1634static int 1635pmap_remove_entry(pmap_t pmap, vm_page_t m, vm_offset_t va) 1636{ 1637 pv_entry_t pv; 1638 int rtval; 1639 int s; 1640 1641 s = splvm(); 1642 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1643 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1644 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1645 if (pmap == pv->pv_pmap && va == pv->pv_va) 1646 break; 1647 } 1648 } else { 1649 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1650 if (va == pv->pv_va) 1651 break; 1652 } 1653 } 1654 1655 rtval = 0; 1656 if (pv) { 1657 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1658 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1659 m->md.pv_list_count--; 1660 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1661 vm_page_flag_clear(m, PG_WRITEABLE); 1662 1663 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1664 free_pv_entry(pv); 1665 } 1666 1667 splx(s); 1668 return rtval; 1669} 1670 1671/* 1672 * Create a pv entry for page at pa for 1673 * (pmap, va). 1674 */ 1675static void 1676pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1677{ 1678 1679 int s; 1680 pv_entry_t pv; 1681 1682 s = splvm(); 1683 pv = get_pv_entry(); 1684 pv->pv_va = va; 1685 pv->pv_pmap = pmap; 1686 pv->pv_ptem = mpte; 1687 1688 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1689 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1690 m->md.pv_list_count++; 1691 1692 splx(s); 1693} 1694 1695/* 1696 * pmap_remove_pte: do the things to unmap a page in a process 1697 */ 1698static int 1699pmap_remove_pte(pmap_t pmap, pt_entry_t *ptq, vm_offset_t va) 1700{ 1701 pt_entry_t oldpte; 1702 vm_page_t m; 1703 1704 oldpte = atomic_readandclear_int(ptq); 1705 if (oldpte & PG_W) 1706 pmap->pm_stats.wired_count -= 1; 1707 /* 1708 * Machines that don't support invlpg, also don't support 1709 * PG_G. 1710 */ 1711 if (oldpte & PG_G) 1712 pmap_invalidate_page(kernel_pmap, va); 1713 pmap->pm_stats.resident_count -= 1; 1714 if (oldpte & PG_MANAGED) { 1715 m = PHYS_TO_VM_PAGE(oldpte); 1716 if (oldpte & PG_M) { 1717#if defined(PMAP_DIAGNOSTIC) 1718 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1719 printf( 1720 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1721 va, oldpte); 1722 } 1723#endif 1724 if (pmap_track_modified(va)) 1725 vm_page_dirty(m); 1726 } 1727 if (oldpte & PG_A) 1728 vm_page_flag_set(m, PG_REFERENCED); 1729 return pmap_remove_entry(pmap, m, va); 1730 } else { 1731 return pmap_unuse_pt(pmap, va, NULL); 1732 } 1733 1734 return 0; 1735} 1736 1737/* 1738 * Remove a single page from a process address space 1739 */ 1740static void 1741pmap_remove_page(pmap_t pmap, vm_offset_t va) 1742{ 1743 register pt_entry_t *ptq; 1744 1745 /* 1746 * if there is no pte for this address, just skip it!!! 1747 */ 1748 if (*pmap_pde(pmap, va) == 0) { 1749 return; 1750 } 1751 1752 /* 1753 * get a local va for mappings for this pmap. 1754 */ 1755 ptq = get_ptbase(pmap) + i386_btop(va); 1756 if (*ptq) { 1757 (void) pmap_remove_pte(pmap, ptq, va); 1758 pmap_invalidate_page(pmap, va); 1759 } 1760 return; 1761} 1762 1763/* 1764 * Remove the given range of addresses from the specified map. 1765 * 1766 * It is assumed that the start and end are properly 1767 * rounded to the page size. 1768 */ 1769void 1770pmap_remove(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1771{ 1772 register pt_entry_t *ptbase; 1773 vm_offset_t pdnxt; 1774 pd_entry_t ptpaddr; 1775 vm_offset_t sindex, eindex; 1776 int anyvalid; 1777 1778 if (pmap == NULL) 1779 return; 1780 1781 if (pmap->pm_stats.resident_count == 0) 1782 return; 1783 1784 /* 1785 * special handling of removing one page. a very 1786 * common operation and easy to short circuit some 1787 * code. 1788 */ 1789 if ((sva + PAGE_SIZE == eva) && 1790 ((pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1791 pmap_remove_page(pmap, sva); 1792 return; 1793 } 1794 1795 anyvalid = 0; 1796 1797 /* 1798 * Get a local virtual address for the mappings that are being 1799 * worked with. 1800 */ 1801 ptbase = get_ptbase(pmap); 1802 1803 sindex = i386_btop(sva); 1804 eindex = i386_btop(eva); 1805 1806 for (; sindex < eindex; sindex = pdnxt) { 1807 unsigned pdirindex; 1808 1809 /* 1810 * Calculate index for next page table. 1811 */ 1812 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1813 if (pmap->pm_stats.resident_count == 0) 1814 break; 1815 1816 pdirindex = sindex / NPDEPG; 1817 ptpaddr = pmap->pm_pdir[pdirindex]; 1818 if ((ptpaddr & PG_PS) != 0) { 1819 pmap->pm_pdir[pdirindex] = 0; 1820 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1821 anyvalid++; 1822 continue; 1823 } 1824 1825 /* 1826 * Weed out invalid mappings. Note: we assume that the page 1827 * directory table is always allocated, and in kernel virtual. 1828 */ 1829 if (ptpaddr == 0) 1830 continue; 1831 1832 /* 1833 * Limit our scan to either the end of the va represented 1834 * by the current page table page, or to the end of the 1835 * range being removed. 1836 */ 1837 if (pdnxt > eindex) { 1838 pdnxt = eindex; 1839 } 1840 1841 for (; sindex != pdnxt; sindex++) { 1842 vm_offset_t va; 1843 if (ptbase[sindex] == 0) { 1844 continue; 1845 } 1846 va = i386_ptob(sindex); 1847 1848 anyvalid++; 1849 if (pmap_remove_pte(pmap, ptbase + sindex, va)) 1850 break; 1851 } 1852 } 1853 1854 if (anyvalid) 1855 pmap_invalidate_all(pmap); 1856} 1857 1858/* 1859 * Routine: pmap_remove_all 1860 * Function: 1861 * Removes this physical page from 1862 * all physical maps in which it resides. 1863 * Reflects back modify bits to the pager. 1864 * 1865 * Notes: 1866 * Original versions of this routine were very 1867 * inefficient because they iteratively called 1868 * pmap_remove (slow...) 1869 */ 1870 1871void 1872pmap_remove_all(vm_page_t m) 1873{ 1874 register pv_entry_t pv; 1875 pt_entry_t *pte, tpte; 1876 int s; 1877 1878#if defined(PMAP_DIAGNOSTIC) 1879 /* 1880 * XXX This makes pmap_remove_all() illegal for non-managed pages! 1881 */ 1882 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1883 panic("pmap_remove_all: illegal for unmanaged page, va: 0x%x", 1884 VM_PAGE_TO_PHYS(m)); 1885 } 1886#endif 1887 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 1888 s = splvm(); 1889 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1890 pv->pv_pmap->pm_stats.resident_count--; 1891 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1892 tpte = atomic_readandclear_int(pte); 1893 if (tpte & PG_W) 1894 pv->pv_pmap->pm_stats.wired_count--; 1895 if (tpte & PG_A) 1896 vm_page_flag_set(m, PG_REFERENCED); 1897 1898 /* 1899 * Update the vm_page_t clean and reference bits. 1900 */ 1901 if (tpte & PG_M) { 1902#if defined(PMAP_DIAGNOSTIC) 1903 if (pmap_nw_modified((pt_entry_t) tpte)) { 1904 printf( 1905 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1906 pv->pv_va, tpte); 1907 } 1908#endif 1909 if (pmap_track_modified(pv->pv_va)) 1910 vm_page_dirty(m); 1911 } 1912 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 1913 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1914 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1915 m->md.pv_list_count--; 1916 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1917 free_pv_entry(pv); 1918 } 1919 vm_page_flag_clear(m, PG_WRITEABLE); 1920 splx(s); 1921} 1922 1923/* 1924 * Set the physical protection on the 1925 * specified range of this map as requested. 1926 */ 1927void 1928pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1929{ 1930 register pt_entry_t *ptbase; 1931 vm_offset_t pdnxt; 1932 pd_entry_t ptpaddr; 1933 vm_offset_t sindex, eindex; 1934 int anychanged; 1935 1936 if (pmap == NULL) 1937 return; 1938 1939 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1940 pmap_remove(pmap, sva, eva); 1941 return; 1942 } 1943 1944 if (prot & VM_PROT_WRITE) 1945 return; 1946 1947 anychanged = 0; 1948 1949 ptbase = get_ptbase(pmap); 1950 1951 sindex = i386_btop(sva); 1952 eindex = i386_btop(eva); 1953 1954 for (; sindex < eindex; sindex = pdnxt) { 1955 1956 unsigned pdirindex; 1957 1958 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1959 1960 pdirindex = sindex / NPDEPG; 1961 ptpaddr = pmap->pm_pdir[pdirindex]; 1962 if ((ptpaddr & PG_PS) != 0) { 1963 pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1964 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1965 anychanged++; 1966 continue; 1967 } 1968 1969 /* 1970 * Weed out invalid mappings. Note: we assume that the page 1971 * directory table is always allocated, and in kernel virtual. 1972 */ 1973 if (ptpaddr == 0) 1974 continue; 1975 1976 if (pdnxt > eindex) { 1977 pdnxt = eindex; 1978 } 1979 1980 for (; sindex != pdnxt; sindex++) { 1981 1982 pt_entry_t pbits; 1983 vm_page_t m; 1984 1985 pbits = ptbase[sindex]; 1986 1987 if (pbits & PG_MANAGED) { 1988 m = NULL; 1989 if (pbits & PG_A) { 1990 m = PHYS_TO_VM_PAGE(pbits); 1991 vm_page_flag_set(m, PG_REFERENCED); 1992 pbits &= ~PG_A; 1993 } 1994 if (pbits & PG_M) { 1995 if (pmap_track_modified(i386_ptob(sindex))) { 1996 if (m == NULL) 1997 m = PHYS_TO_VM_PAGE(pbits); 1998 vm_page_dirty(m); 1999 pbits &= ~PG_M; 2000 } 2001 } 2002 } 2003 2004 pbits &= ~PG_RW; 2005 2006 if (pbits != ptbase[sindex]) { 2007 ptbase[sindex] = pbits; 2008 anychanged = 1; 2009 } 2010 } 2011 } 2012 if (anychanged) 2013 pmap_invalidate_all(pmap); 2014} 2015 2016/* 2017 * Insert the given physical page (p) at 2018 * the specified virtual address (v) in the 2019 * target physical map with the protection requested. 2020 * 2021 * If specified, the page will be wired down, meaning 2022 * that the related pte can not be reclaimed. 2023 * 2024 * NB: This is the only routine which MAY NOT lazy-evaluate 2025 * or lose information. That is, this routine must actually 2026 * insert this page into the given map NOW. 2027 */ 2028void 2029pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2030 boolean_t wired) 2031{ 2032 vm_offset_t pa; 2033 register pt_entry_t *pte; 2034 vm_offset_t opa; 2035 pt_entry_t origpte, newpte; 2036 vm_page_t mpte; 2037 2038 if (pmap == NULL) 2039 return; 2040 2041 va &= PG_FRAME; 2042#ifdef PMAP_DIAGNOSTIC 2043 if (va > VM_MAX_KERNEL_ADDRESS) 2044 panic("pmap_enter: toobig"); 2045 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 2046 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 2047#endif 2048 2049 mpte = NULL; 2050 /* 2051 * In the case that a page table page is not 2052 * resident, we are creating it here. 2053 */ 2054 if (va < VM_MAXUSER_ADDRESS) { 2055 mpte = pmap_allocpte(pmap, va); 2056 } 2057#if 0 && defined(PMAP_DIAGNOSTIC) 2058 else { 2059 pd_entry_t *pdeaddr = pmap_pde(pmap, va); 2060 origpte = *pdeaddr; 2061 if ((origpte & PG_V) == 0) { 2062 panic("pmap_enter: invalid kernel page table page, pdir=%p, pde=%p, va=%p\n", 2063 pmap->pm_pdir[PTDPTDI], origpte, va); 2064 } 2065 } 2066#endif 2067 2068 pte = pmap_pte(pmap, va); 2069 2070 /* 2071 * Page Directory table entry not valid, we need a new PT page 2072 */ 2073 if (pte == NULL) { 2074 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 2075 (void *)pmap->pm_pdir[PTDPTDI], va); 2076 } 2077 2078 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 2079 origpte = *(vm_offset_t *)pte; 2080 opa = origpte & PG_FRAME; 2081 2082 if (origpte & PG_PS) 2083 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2084 2085 /* 2086 * Mapping has not changed, must be protection or wiring change. 2087 */ 2088 if (origpte && (opa == pa)) { 2089 /* 2090 * Wiring change, just update stats. We don't worry about 2091 * wiring PT pages as they remain resident as long as there 2092 * are valid mappings in them. Hence, if a user page is wired, 2093 * the PT page will be also. 2094 */ 2095 if (wired && ((origpte & PG_W) == 0)) 2096 pmap->pm_stats.wired_count++; 2097 else if (!wired && (origpte & PG_W)) 2098 pmap->pm_stats.wired_count--; 2099 2100#if defined(PMAP_DIAGNOSTIC) 2101 if (pmap_nw_modified((pt_entry_t) origpte)) { 2102 printf( 2103 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2104 va, origpte); 2105 } 2106#endif 2107 2108 /* 2109 * Remove extra pte reference 2110 */ 2111 if (mpte) 2112 mpte->hold_count--; 2113 2114 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2115 if ((origpte & PG_RW) == 0) { 2116 *pte |= PG_RW; 2117 pmap_invalidate_page(pmap, va); 2118 } 2119 return; 2120 } 2121 2122 /* 2123 * We might be turning off write access to the page, 2124 * so we go ahead and sense modify status. 2125 */ 2126 if (origpte & PG_MANAGED) { 2127 if ((origpte & PG_M) && pmap_track_modified(va)) { 2128 vm_page_t om; 2129 om = PHYS_TO_VM_PAGE(opa); 2130 vm_page_dirty(om); 2131 } 2132 pa |= PG_MANAGED; 2133 } 2134 goto validate; 2135 } 2136 /* 2137 * Mapping has changed, invalidate old range and fall through to 2138 * handle validating new mapping. 2139 */ 2140 if (opa) { 2141 int err; 2142 vm_page_lock_queues(); 2143 err = pmap_remove_pte(pmap, pte, va); 2144 vm_page_unlock_queues(); 2145 if (err) 2146 panic("pmap_enter: pte vanished, va: 0x%x", va); 2147 } 2148 2149 /* 2150 * Enter on the PV list if part of our managed memory. Note that we 2151 * raise IPL while manipulating pv_table since pmap_enter can be 2152 * called at interrupt time. 2153 */ 2154 if (pmap_initialized && 2155 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2156 pmap_insert_entry(pmap, va, mpte, m); 2157 pa |= PG_MANAGED; 2158 } 2159 2160 /* 2161 * Increment counters 2162 */ 2163 pmap->pm_stats.resident_count++; 2164 if (wired) 2165 pmap->pm_stats.wired_count++; 2166 2167validate: 2168 /* 2169 * Now validate mapping with desired protection/wiring. 2170 */ 2171 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2172 2173 if (wired) 2174 newpte |= PG_W; 2175 if (va < VM_MAXUSER_ADDRESS) 2176 newpte |= PG_U; 2177 if (pmap == kernel_pmap) 2178 newpte |= pgeflag; 2179 2180 /* 2181 * if the mapping or permission bits are different, we need 2182 * to update the pte. 2183 */ 2184 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2185 *pte = newpte | PG_A; 2186 /*if (origpte)*/ { 2187 pmap_invalidate_page(pmap, va); 2188 } 2189 } 2190} 2191 2192/* 2193 * this code makes some *MAJOR* assumptions: 2194 * 1. Current pmap & pmap exists. 2195 * 2. Not wired. 2196 * 3. Read access. 2197 * 4. No page table pages. 2198 * 5. Tlbflush is deferred to calling procedure. 2199 * 6. Page IS managed. 2200 * but is *MUCH* faster than pmap_enter... 2201 */ 2202 2203static vm_page_t 2204pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_page_t mpte) 2205{ 2206 pt_entry_t *pte; 2207 vm_offset_t pa; 2208 2209 /* 2210 * In the case that a page table page is not 2211 * resident, we are creating it here. 2212 */ 2213 if (va < VM_MAXUSER_ADDRESS) { 2214 unsigned ptepindex; 2215 pd_entry_t ptepa; 2216 2217 /* 2218 * Calculate pagetable page index 2219 */ 2220 ptepindex = va >> PDRSHIFT; 2221 if (mpte && (mpte->pindex == ptepindex)) { 2222 mpte->hold_count++; 2223 } else { 2224retry: 2225 /* 2226 * Get the page directory entry 2227 */ 2228 ptepa = pmap->pm_pdir[ptepindex]; 2229 2230 /* 2231 * If the page table page is mapped, we just increment 2232 * the hold count, and activate it. 2233 */ 2234 if (ptepa) { 2235 if (ptepa & PG_PS) 2236 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2237 if (pmap->pm_ptphint && 2238 (pmap->pm_ptphint->pindex == ptepindex)) { 2239 mpte = pmap->pm_ptphint; 2240 } else { 2241 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 2242 pmap->pm_ptphint = mpte; 2243 } 2244 if (mpte == NULL) 2245 goto retry; 2246 mpte->hold_count++; 2247 } else { 2248 mpte = _pmap_allocpte(pmap, ptepindex); 2249 } 2250 } 2251 } else { 2252 mpte = NULL; 2253 } 2254 2255 /* 2256 * This call to vtopte makes the assumption that we are 2257 * entering the page into the current pmap. In order to support 2258 * quick entry into any pmap, one would likely use pmap_pte_quick. 2259 * But that isn't as quick as vtopte. 2260 */ 2261 pte = vtopte(va); 2262 if (*pte) { 2263 if (mpte != NULL) { 2264 vm_page_lock_queues(); 2265 pmap_unwire_pte_hold(pmap, mpte); 2266 vm_page_unlock_queues(); 2267 } 2268 return 0; 2269 } 2270 2271 /* 2272 * Enter on the PV list if part of our managed memory. Note that we 2273 * raise IPL while manipulating pv_table since pmap_enter can be 2274 * called at interrupt time. 2275 */ 2276 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2277 pmap_insert_entry(pmap, va, mpte, m); 2278 2279 /* 2280 * Increment counters 2281 */ 2282 pmap->pm_stats.resident_count++; 2283 2284 pa = VM_PAGE_TO_PHYS(m); 2285 2286 /* 2287 * Now validate mapping with RO protection 2288 */ 2289 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2290 *pte = pa | PG_V | PG_U; 2291 else 2292 *pte = pa | PG_V | PG_U | PG_MANAGED; 2293 2294 return mpte; 2295} 2296 2297/* 2298 * Make a temporary mapping for a physical address. This is only intended 2299 * to be used for panic dumps. 2300 */ 2301void * 2302pmap_kenter_temporary(vm_offset_t pa, int i) 2303{ 2304 vm_offset_t va; 2305 2306 va = (vm_offset_t)crashdumpmap + (i * PAGE_SIZE); 2307 pmap_kenter(va, pa); 2308#ifndef I386_CPU 2309 invlpg(va); 2310#else 2311 invltlb(); 2312#endif 2313 return ((void *)crashdumpmap); 2314} 2315 2316#define MAX_INIT_PT (96) 2317/* 2318 * pmap_object_init_pt preloads the ptes for a given object 2319 * into the specified pmap. This eliminates the blast of soft 2320 * faults on process startup and immediately after an mmap. 2321 */ 2322void 2323pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, 2324 vm_object_t object, vm_pindex_t pindex, 2325 vm_size_t size, int limit) 2326{ 2327 vm_offset_t tmpidx; 2328 int psize; 2329 vm_page_t p, mpte; 2330 2331 if (pmap == NULL || object == NULL) 2332 return; 2333 2334 /* 2335 * This code maps large physical mmap regions into the 2336 * processor address space. Note that some shortcuts 2337 * are taken, but the code works. 2338 */ 2339 if (pseflag && (object->type == OBJT_DEVICE) && 2340 ((addr & (NBPDR - 1)) == 0) && ((size & (NBPDR - 1)) == 0)) { 2341 int i; 2342 vm_page_t m[1]; 2343 unsigned int ptepindex; 2344 int npdes; 2345 pd_entry_t ptepa; 2346 2347 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2348 return; 2349 2350retry: 2351 p = vm_page_lookup(object, pindex); 2352 if (p != NULL) { 2353 vm_page_lock_queues(); 2354 if (vm_page_sleep_if_busy(p, FALSE, "init4p")) 2355 goto retry; 2356 } else { 2357 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2358 if (p == NULL) 2359 return; 2360 m[0] = p; 2361 2362 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2363 vm_page_lock_queues(); 2364 vm_page_free(p); 2365 vm_page_unlock_queues(); 2366 return; 2367 } 2368 2369 p = vm_page_lookup(object, pindex); 2370 vm_page_lock_queues(); 2371 vm_page_wakeup(p); 2372 } 2373 vm_page_unlock_queues(); 2374 2375 ptepa = VM_PAGE_TO_PHYS(p); 2376 if (ptepa & (NBPDR - 1)) { 2377 return; 2378 } 2379 2380 p->valid = VM_PAGE_BITS_ALL; 2381 2382 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2383 npdes = size >> PDRSHIFT; 2384 for(i = 0; i < npdes; i++) { 2385 pmap->pm_pdir[ptepindex] = 2386 ptepa | PG_U | PG_RW | PG_V | PG_PS; 2387 ptepa += NBPDR; 2388 ptepindex += 1; 2389 } 2390 pmap_invalidate_all(kernel_pmap); 2391 return; 2392 } 2393 2394 psize = i386_btop(size); 2395 2396 if ((object->type != OBJT_VNODE) || 2397 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2398 (object->resident_page_count > MAX_INIT_PT))) { 2399 return; 2400 } 2401 2402 if (psize + pindex > object->size) { 2403 if (object->size < pindex) 2404 return; 2405 psize = object->size - pindex; 2406 } 2407 2408 mpte = NULL; 2409 2410 if ((p = TAILQ_FIRST(&object->memq)) != NULL) { 2411 if (p->pindex < pindex) { 2412 p = vm_page_splay(pindex, object->root); 2413 if ((object->root = p)->pindex < pindex) 2414 p = TAILQ_NEXT(p, listq); 2415 } 2416 } 2417 /* 2418 * Assert: the variable p is either (1) the page with the 2419 * least pindex greater than or equal to the parameter pindex 2420 * or (2) NULL. 2421 */ 2422 for (; 2423 p != NULL && (tmpidx = p->pindex - pindex) < psize; 2424 p = TAILQ_NEXT(p, listq)) { 2425 /* 2426 * don't allow an madvise to blow away our really 2427 * free pages allocating pv entries. 2428 */ 2429 if ((limit & MAP_PREFAULT_MADVISE) && 2430 cnt.v_free_count < cnt.v_free_reserved) { 2431 break; 2432 } 2433 vm_page_lock_queues(); 2434 if ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL && 2435 (p->busy == 0) && 2436 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2437 if ((p->queue - p->pc) == PQ_CACHE) 2438 vm_page_deactivate(p); 2439 vm_page_busy(p); 2440 vm_page_unlock_queues(); 2441 mpte = pmap_enter_quick(pmap, 2442 addr + i386_ptob(tmpidx), p, mpte); 2443 vm_page_lock_queues(); 2444 vm_page_wakeup(p); 2445 } 2446 vm_page_unlock_queues(); 2447 } 2448 return; 2449} 2450 2451/* 2452 * pmap_prefault provides a quick way of clustering 2453 * pagefaults into a processes address space. It is a "cousin" 2454 * of pmap_object_init_pt, except it runs at page fault time instead 2455 * of mmap time. 2456 */ 2457#define PFBAK 4 2458#define PFFOR 4 2459#define PAGEORDER_SIZE (PFBAK+PFFOR) 2460 2461static int pmap_prefault_pageorder[] = { 2462 -1 * PAGE_SIZE, 1 * PAGE_SIZE, 2463 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2464 -3 * PAGE_SIZE, 3 * PAGE_SIZE, 2465 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2466}; 2467 2468void 2469pmap_prefault(pmap, addra, entry) 2470 pmap_t pmap; 2471 vm_offset_t addra; 2472 vm_map_entry_t entry; 2473{ 2474 int i; 2475 vm_offset_t starta; 2476 vm_offset_t addr; 2477 vm_pindex_t pindex; 2478 vm_page_t m, mpte; 2479 vm_object_t object; 2480 2481 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) 2482 return; 2483 2484 object = entry->object.vm_object; 2485 2486 starta = addra - PFBAK * PAGE_SIZE; 2487 if (starta < entry->start) { 2488 starta = entry->start; 2489 } else if (starta > addra) { 2490 starta = 0; 2491 } 2492 2493 mpte = NULL; 2494 for (i = 0; i < PAGEORDER_SIZE; i++) { 2495 vm_object_t lobject; 2496 pt_entry_t *pte; 2497 2498 addr = addra + pmap_prefault_pageorder[i]; 2499 if (addr > addra + (PFFOR * PAGE_SIZE)) 2500 addr = 0; 2501 2502 if (addr < starta || addr >= entry->end) 2503 continue; 2504 2505 if ((*pmap_pde(pmap, addr)) == 0) 2506 continue; 2507 2508 pte = vtopte(addr); 2509 if (*pte) 2510 continue; 2511 2512 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2513 lobject = object; 2514 for (m = vm_page_lookup(lobject, pindex); 2515 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2516 lobject = lobject->backing_object) { 2517 if (lobject->backing_object_offset & PAGE_MASK) 2518 break; 2519 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2520 m = vm_page_lookup(lobject->backing_object, pindex); 2521 } 2522 2523 /* 2524 * give-up when a page is not in memory 2525 */ 2526 if (m == NULL) 2527 break; 2528 vm_page_lock_queues(); 2529 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2530 (m->busy == 0) && 2531 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2532 2533 if ((m->queue - m->pc) == PQ_CACHE) { 2534 vm_page_deactivate(m); 2535 } 2536 vm_page_busy(m); 2537 vm_page_unlock_queues(); 2538 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2539 vm_page_lock_queues(); 2540 vm_page_wakeup(m); 2541 } 2542 vm_page_unlock_queues(); 2543 } 2544} 2545 2546/* 2547 * Routine: pmap_change_wiring 2548 * Function: Change the wiring attribute for a map/virtual-address 2549 * pair. 2550 * In/out conditions: 2551 * The mapping must already exist in the pmap. 2552 */ 2553void 2554pmap_change_wiring(pmap, va, wired) 2555 register pmap_t pmap; 2556 vm_offset_t va; 2557 boolean_t wired; 2558{ 2559 register pt_entry_t *pte; 2560 2561 if (pmap == NULL) 2562 return; 2563 2564 pte = pmap_pte(pmap, va); 2565 2566 if (wired && !pmap_pte_w(pte)) 2567 pmap->pm_stats.wired_count++; 2568 else if (!wired && pmap_pte_w(pte)) 2569 pmap->pm_stats.wired_count--; 2570 2571 /* 2572 * Wiring is not a hardware characteristic so there is no need to 2573 * invalidate TLB. 2574 */ 2575 pmap_pte_set_w(pte, wired); 2576} 2577 2578 2579 2580/* 2581 * Copy the range specified by src_addr/len 2582 * from the source map to the range dst_addr/len 2583 * in the destination map. 2584 * 2585 * This routine is only advisory and need not do anything. 2586 */ 2587 2588void 2589pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, vm_size_t len, 2590 vm_offset_t src_addr) 2591{ 2592 vm_offset_t addr; 2593 vm_offset_t end_addr = src_addr + len; 2594 vm_offset_t pdnxt; 2595 pd_entry_t src_frame, dst_frame; 2596 vm_page_t m; 2597 2598 if (dst_addr != src_addr) 2599 return; 2600 2601 src_frame = src_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2602 if (src_frame != (PTDpde & PG_FRAME)) 2603 return; 2604 2605 dst_frame = dst_pmap->pm_pdir[PTDPTDI] & PG_FRAME; 2606 for (addr = src_addr; addr < end_addr; addr = pdnxt) { 2607 pt_entry_t *src_pte, *dst_pte; 2608 vm_page_t dstmpte, srcmpte; 2609 pd_entry_t srcptepaddr; 2610 unsigned ptepindex; 2611 2612 if (addr >= UPT_MIN_ADDRESS) 2613 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2614 2615 /* 2616 * Don't let optional prefaulting of pages make us go 2617 * way below the low water mark of free pages or way 2618 * above high water mark of used pv entries. 2619 */ 2620 if (cnt.v_free_count < cnt.v_free_reserved || 2621 pv_entry_count > pv_entry_high_water) 2622 break; 2623 2624 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2625 ptepindex = addr >> PDRSHIFT; 2626 2627 srcptepaddr = src_pmap->pm_pdir[ptepindex]; 2628 if (srcptepaddr == 0) 2629 continue; 2630 2631 if (srcptepaddr & PG_PS) { 2632 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2633 dst_pmap->pm_pdir[ptepindex] = srcptepaddr; 2634 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2635 } 2636 continue; 2637 } 2638 2639 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2640 if ((srcmpte == NULL) || 2641 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2642 continue; 2643 2644 if (pdnxt > end_addr) 2645 pdnxt = end_addr; 2646 2647 /* 2648 * Have to recheck this before every avtopte() call below 2649 * in case we have blocked and something else used APTDpde. 2650 */ 2651 if (dst_frame != (APTDpde & PG_FRAME)) { 2652 APTDpde = dst_frame | PG_RW | PG_V; 2653 pmap_invalidate_all(kernel_pmap); /* XXX Bandaid */ 2654 } 2655 src_pte = vtopte(addr); 2656 dst_pte = avtopte(addr); 2657 while (addr < pdnxt) { 2658 pt_entry_t ptetemp; 2659 ptetemp = *src_pte; 2660 /* 2661 * we only virtual copy managed pages 2662 */ 2663 if ((ptetemp & PG_MANAGED) != 0) { 2664 /* 2665 * We have to check after allocpte for the 2666 * pte still being around... allocpte can 2667 * block. 2668 */ 2669 dstmpte = pmap_allocpte(dst_pmap, addr); 2670 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2671 /* 2672 * Clear the modified and 2673 * accessed (referenced) bits 2674 * during the copy. 2675 */ 2676 m = PHYS_TO_VM_PAGE(ptetemp); 2677 *dst_pte = ptetemp & ~(PG_M | PG_A); 2678 dst_pmap->pm_stats.resident_count++; 2679 pmap_insert_entry(dst_pmap, addr, 2680 dstmpte, m); 2681 } else { 2682 vm_page_lock_queues(); 2683 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2684 vm_page_unlock_queues(); 2685 } 2686 if (dstmpte->hold_count >= srcmpte->hold_count) 2687 break; 2688 } 2689 addr += PAGE_SIZE; 2690 src_pte++; 2691 dst_pte++; 2692 } 2693 } 2694} 2695 2696#ifdef SMP 2697 2698/* 2699 * pmap_zpi_switchin*() 2700 * 2701 * These functions allow us to avoid doing IPIs alltogether in certain 2702 * temporary page-mapping situations (page zeroing). Instead to deal 2703 * with being preempted and moved onto a different cpu we invalidate 2704 * the page when the scheduler switches us in. This does not occur 2705 * very often so we remain relatively optimal with very little effort. 2706 */ 2707static void 2708pmap_zpi_switchin12(void) 2709{ 2710 invlpg((u_int)CADDR1); 2711 invlpg((u_int)CADDR2); 2712} 2713 2714static void 2715pmap_zpi_switchin2(void) 2716{ 2717 invlpg((u_int)CADDR2); 2718} 2719 2720static void 2721pmap_zpi_switchin3(void) 2722{ 2723 invlpg((u_int)CADDR3); 2724} 2725 2726#endif 2727 2728/* 2729 * pmap_zero_page zeros the specified hardware page by mapping 2730 * the page into KVM and using bzero to clear its contents. 2731 */ 2732void 2733pmap_zero_page(vm_page_t m) 2734{ 2735 vm_offset_t phys; 2736 2737 phys = VM_PAGE_TO_PHYS(m); 2738 if (*CMAP2) 2739 panic("pmap_zero_page: CMAP2 busy"); 2740 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2741#ifdef I386_CPU 2742 invltlb(); 2743#else 2744#ifdef SMP 2745 curthread->td_switchin = pmap_zpi_switchin2; 2746#endif 2747 invlpg((u_int)CADDR2); 2748#endif 2749#if defined(I686_CPU) 2750 if (cpu_class == CPUCLASS_686) 2751 i686_pagezero(CADDR2); 2752 else 2753#endif 2754 bzero(CADDR2, PAGE_SIZE); 2755#ifdef SMP 2756 curthread->td_switchin = NULL; 2757#endif 2758 *CMAP2 = 0; 2759} 2760 2761/* 2762 * pmap_zero_page_area zeros the specified hardware page by mapping 2763 * the page into KVM and using bzero to clear its contents. 2764 * 2765 * off and size may not cover an area beyond a single hardware page. 2766 */ 2767void 2768pmap_zero_page_area(vm_page_t m, int off, int size) 2769{ 2770 vm_offset_t phys; 2771 2772 phys = VM_PAGE_TO_PHYS(m); 2773 if (*CMAP2) 2774 panic("pmap_zero_page: CMAP2 busy"); 2775 *CMAP2 = PG_V | PG_RW | phys | PG_A | PG_M; 2776#ifdef I386_CPU 2777 invltlb(); 2778#else 2779#ifdef SMP 2780 curthread->td_switchin = pmap_zpi_switchin2; 2781#endif 2782 invlpg((u_int)CADDR2); 2783#endif 2784#if defined(I686_CPU) 2785 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2786 i686_pagezero(CADDR2); 2787 else 2788#endif 2789 bzero((char *)CADDR2 + off, size); 2790#ifdef SMP 2791 curthread->td_switchin = NULL; 2792#endif 2793 *CMAP2 = 0; 2794} 2795 2796/* 2797 * pmap_zero_page_idle zeros the specified hardware page by mapping 2798 * the page into KVM and using bzero to clear its contents. This 2799 * is intended to be called from the vm_pagezero process only and 2800 * outside of Giant. 2801 */ 2802void 2803pmap_zero_page_idle(vm_page_t m) 2804{ 2805 vm_offset_t phys; 2806 2807 phys = VM_PAGE_TO_PHYS(m); 2808 if (*CMAP3) 2809 panic("pmap_zero_page: CMAP3 busy"); 2810 *CMAP3 = PG_V | PG_RW | phys | PG_A | PG_M; 2811#ifdef I386_CPU 2812 invltlb(); 2813#else 2814#ifdef SMP 2815 curthread->td_switchin = pmap_zpi_switchin3; 2816#endif 2817 invlpg((u_int)CADDR3); 2818#endif 2819#if defined(I686_CPU) 2820 if (cpu_class == CPUCLASS_686) 2821 i686_pagezero(CADDR3); 2822 else 2823#endif 2824 bzero(CADDR3, PAGE_SIZE); 2825#ifdef SMP 2826 curthread->td_switchin = NULL; 2827#endif 2828 *CMAP3 = 0; 2829} 2830 2831/* 2832 * pmap_copy_page copies the specified (machine independent) 2833 * page by mapping the page into virtual memory and using 2834 * bcopy to copy the page, one machine dependent page at a 2835 * time. 2836 */ 2837void 2838pmap_copy_page(vm_page_t src, vm_page_t dst) 2839{ 2840 2841 if (*CMAP1) 2842 panic("pmap_copy_page: CMAP1 busy"); 2843 if (*CMAP2) 2844 panic("pmap_copy_page: CMAP2 busy"); 2845 *CMAP1 = PG_V | VM_PAGE_TO_PHYS(src) | PG_A; 2846 *CMAP2 = PG_V | PG_RW | VM_PAGE_TO_PHYS(dst) | PG_A | PG_M; 2847#ifdef I386_CPU 2848 invltlb(); 2849#else 2850#ifdef SMP 2851 curthread->td_switchin = pmap_zpi_switchin12; 2852#endif 2853 invlpg((u_int)CADDR1); 2854 invlpg((u_int)CADDR2); 2855#endif 2856 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2857#ifdef SMP 2858 curthread->td_switchin = NULL; 2859#endif 2860 *CMAP1 = 0; 2861 *CMAP2 = 0; 2862} 2863 2864/* 2865 * Returns true if the pmap's pv is one of the first 2866 * 16 pvs linked to from this page. This count may 2867 * be changed upwards or downwards in the future; it 2868 * is only necessary that true be returned for a small 2869 * subset of pmaps for proper page aging. 2870 */ 2871boolean_t 2872pmap_page_exists_quick(pmap, m) 2873 pmap_t pmap; 2874 vm_page_t m; 2875{ 2876 pv_entry_t pv; 2877 int loops = 0; 2878 int s; 2879 2880 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2881 return FALSE; 2882 2883 s = splvm(); 2884 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 2885 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2886 if (pv->pv_pmap == pmap) { 2887 splx(s); 2888 return TRUE; 2889 } 2890 loops++; 2891 if (loops >= 16) 2892 break; 2893 } 2894 splx(s); 2895 return (FALSE); 2896} 2897 2898#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2899/* 2900 * Remove all pages from specified address space 2901 * this aids process exit speeds. Also, this code 2902 * is special cased for current process only, but 2903 * can have the more generic (and slightly slower) 2904 * mode enabled. This is much faster than pmap_remove 2905 * in the case of running down an entire address space. 2906 */ 2907void 2908pmap_remove_pages(pmap, sva, eva) 2909 pmap_t pmap; 2910 vm_offset_t sva, eva; 2911{ 2912 pt_entry_t *pte, tpte; 2913 vm_page_t m; 2914 pv_entry_t pv, npv; 2915 int s; 2916 2917#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2918 if (!curthread || (pmap != vmspace_pmap(curthread->td_proc->p_vmspace))) { 2919 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2920 return; 2921 } 2922#endif 2923 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 2924 s = splvm(); 2925 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2926 2927 if (pv->pv_va >= eva || pv->pv_va < sva) { 2928 npv = TAILQ_NEXT(pv, pv_plist); 2929 continue; 2930 } 2931 2932#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2933 pte = vtopte(pv->pv_va); 2934#else 2935 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2936#endif 2937 tpte = *pte; 2938 2939 if (tpte == 0) { 2940 printf("TPTE at %p IS ZERO @ VA %08x\n", 2941 pte, pv->pv_va); 2942 panic("bad pte"); 2943 } 2944 2945/* 2946 * We cannot remove wired pages from a process' mapping at this time 2947 */ 2948 if (tpte & PG_W) { 2949 npv = TAILQ_NEXT(pv, pv_plist); 2950 continue; 2951 } 2952 2953 m = PHYS_TO_VM_PAGE(tpte); 2954 KASSERT(m->phys_addr == (tpte & PG_FRAME), 2955 ("vm_page_t %p phys_addr mismatch %08x %08x", 2956 m, m->phys_addr, tpte)); 2957 2958 KASSERT(m < &vm_page_array[vm_page_array_size], 2959 ("pmap_remove_pages: bad tpte %x", tpte)); 2960 2961 pv->pv_pmap->pm_stats.resident_count--; 2962 2963 *pte = 0; 2964 2965 /* 2966 * Update the vm_page_t clean and reference bits. 2967 */ 2968 if (tpte & PG_M) { 2969 vm_page_dirty(m); 2970 } 2971 2972 npv = TAILQ_NEXT(pv, pv_plist); 2973 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 2974 2975 m->md.pv_list_count--; 2976 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 2977 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 2978 vm_page_flag_clear(m, PG_WRITEABLE); 2979 } 2980 2981 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 2982 free_pv_entry(pv); 2983 } 2984 splx(s); 2985 pmap_invalidate_all(pmap); 2986} 2987 2988/* 2989 * pmap_is_modified: 2990 * 2991 * Return whether or not the specified physical page was modified 2992 * in any physical maps. 2993 */ 2994boolean_t 2995pmap_is_modified(vm_page_t m) 2996{ 2997 pv_entry_t pv; 2998 pt_entry_t *pte; 2999 int s; 3000 3001 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3002 return FALSE; 3003 3004 s = splvm(); 3005 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 3006 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3007 /* 3008 * if the bit being tested is the modified bit, then 3009 * mark clean_map and ptes as never 3010 * modified. 3011 */ 3012 if (!pmap_track_modified(pv->pv_va)) 3013 continue; 3014#if defined(PMAP_DIAGNOSTIC) 3015 if (!pv->pv_pmap) { 3016 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 3017 continue; 3018 } 3019#endif 3020 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3021 if (*pte & PG_M) { 3022 splx(s); 3023 return TRUE; 3024 } 3025 } 3026 splx(s); 3027 return (FALSE); 3028} 3029 3030/* 3031 * this routine is used to modify bits in ptes 3032 */ 3033static __inline void 3034pmap_changebit(vm_page_t m, int bit, boolean_t setem) 3035{ 3036 register pv_entry_t pv; 3037 register pt_entry_t *pte; 3038 int s; 3039 3040 if (!pmap_initialized || (m->flags & PG_FICTITIOUS) || 3041 (!setem && bit == PG_RW && (m->flags & PG_WRITEABLE) == 0)) 3042 return; 3043 3044 s = splvm(); 3045 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 3046 /* 3047 * Loop over all current mappings setting/clearing as appropos If 3048 * setting RO do we need to clear the VAC? 3049 */ 3050 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3051 /* 3052 * don't write protect pager mappings 3053 */ 3054 if (!setem && (bit == PG_RW)) { 3055 if (!pmap_track_modified(pv->pv_va)) 3056 continue; 3057 } 3058 3059#if defined(PMAP_DIAGNOSTIC) 3060 if (!pv->pv_pmap) { 3061 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 3062 continue; 3063 } 3064#endif 3065 3066 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3067 3068 if (setem) { 3069 *pte |= bit; 3070 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3071 } else { 3072 pt_entry_t pbits = *pte; 3073 if (pbits & bit) { 3074 if (bit == PG_RW) { 3075 if (pbits & PG_M) { 3076 vm_page_dirty(m); 3077 } 3078 *pte = pbits & ~(PG_M|PG_RW); 3079 } else { 3080 *pte = pbits & ~bit; 3081 } 3082 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3083 } 3084 } 3085 } 3086 if (!setem && bit == PG_RW) 3087 vm_page_flag_clear(m, PG_WRITEABLE); 3088 splx(s); 3089} 3090 3091/* 3092 * pmap_page_protect: 3093 * 3094 * Lower the permission for all mappings to a given page. 3095 */ 3096void 3097pmap_page_protect(vm_page_t m, vm_prot_t prot) 3098{ 3099 if ((prot & VM_PROT_WRITE) == 0) { 3100 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3101 pmap_changebit(m, PG_RW, FALSE); 3102 } else { 3103 pmap_remove_all(m); 3104 } 3105 } 3106} 3107 3108vm_offset_t 3109pmap_phys_address(ppn) 3110 int ppn; 3111{ 3112 return (i386_ptob(ppn)); 3113} 3114 3115/* 3116 * pmap_ts_referenced: 3117 * 3118 * Return a count of reference bits for a page, clearing those bits. 3119 * It is not necessary for every reference bit to be cleared, but it 3120 * is necessary that 0 only be returned when there are truly no 3121 * reference bits set. 3122 * 3123 * XXX: The exact number of bits to check and clear is a matter that 3124 * should be tested and standardized at some point in the future for 3125 * optimal aging of shared pages. 3126 */ 3127int 3128pmap_ts_referenced(vm_page_t m) 3129{ 3130 register pv_entry_t pv, pvf, pvn; 3131 pt_entry_t *pte; 3132 int s; 3133 int rtval = 0; 3134 3135 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3136 return (rtval); 3137 3138 s = splvm(); 3139 mtx_assert(&vm_page_queue_mtx, MA_OWNED); 3140 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3141 3142 pvf = pv; 3143 3144 do { 3145 pvn = TAILQ_NEXT(pv, pv_list); 3146 3147 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3148 3149 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3150 3151 if (!pmap_track_modified(pv->pv_va)) 3152 continue; 3153 3154 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3155 3156 if (pte && (*pte & PG_A)) { 3157 *pte &= ~PG_A; 3158 3159 pmap_invalidate_page(pv->pv_pmap, pv->pv_va); 3160 3161 rtval++; 3162 if (rtval > 4) { 3163 break; 3164 } 3165 } 3166 } while ((pv = pvn) != NULL && pv != pvf); 3167 } 3168 splx(s); 3169 3170 return (rtval); 3171} 3172 3173/* 3174 * Clear the modify bits on the specified physical page. 3175 */ 3176void 3177pmap_clear_modify(vm_page_t m) 3178{ 3179 pmap_changebit(m, PG_M, FALSE); 3180} 3181 3182/* 3183 * pmap_clear_reference: 3184 * 3185 * Clear the reference bit on the specified physical page. 3186 */ 3187void 3188pmap_clear_reference(vm_page_t m) 3189{ 3190 pmap_changebit(m, PG_A, FALSE); 3191} 3192 3193/* 3194 * Miscellaneous support routines follow 3195 */ 3196 3197static void 3198i386_protection_init() 3199{ 3200 register int *kp, prot; 3201 3202 kp = protection_codes; 3203 for (prot = 0; prot < 8; prot++) { 3204 switch (prot) { 3205 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3206 /* 3207 * Read access is also 0. There isn't any execute bit, 3208 * so just make it readable. 3209 */ 3210 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3211 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3212 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3213 *kp++ = 0; 3214 break; 3215 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3216 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3217 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3218 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3219 *kp++ = PG_RW; 3220 break; 3221 } 3222 } 3223} 3224 3225/* 3226 * Map a set of physical memory pages into the kernel virtual 3227 * address space. Return a pointer to where it is mapped. This 3228 * routine is intended to be used for mapping device memory, 3229 * NOT real memory. 3230 */ 3231void * 3232pmap_mapdev(pa, size) 3233 vm_offset_t pa; 3234 vm_size_t size; 3235{ 3236 vm_offset_t va, tmpva, offset; 3237 3238 offset = pa & PAGE_MASK; 3239 size = roundup(offset + size, PAGE_SIZE); 3240 3241 GIANT_REQUIRED; 3242 3243 va = kmem_alloc_pageable(kernel_map, size); 3244 if (!va) 3245 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3246 3247 pa = pa & PG_FRAME; 3248 for (tmpva = va; size > 0; ) { 3249 pmap_kenter(tmpva, pa); 3250 size -= PAGE_SIZE; 3251 tmpva += PAGE_SIZE; 3252 pa += PAGE_SIZE; 3253 } 3254 pmap_invalidate_range(kernel_pmap, va, tmpva); 3255 return ((void *)(va + offset)); 3256} 3257 3258void 3259pmap_unmapdev(va, size) 3260 vm_offset_t va; 3261 vm_size_t size; 3262{ 3263 vm_offset_t base, offset, tmpva; 3264 pt_entry_t *pte; 3265 3266 base = va & PG_FRAME; 3267 offset = va & PAGE_MASK; 3268 size = roundup(offset + size, PAGE_SIZE); 3269 for (tmpva = base; tmpva < (base + size); tmpva += PAGE_SIZE) { 3270 pte = vtopte(tmpva); 3271 *pte = 0; 3272 } 3273 pmap_invalidate_range(kernel_pmap, va, tmpva); 3274 kmem_free(kernel_map, base, size); 3275} 3276 3277/* 3278 * perform the pmap work for mincore 3279 */ 3280int 3281pmap_mincore(pmap, addr) 3282 pmap_t pmap; 3283 vm_offset_t addr; 3284{ 3285 pt_entry_t *ptep, pte; 3286 vm_page_t m; 3287 int val = 0; 3288 3289 ptep = pmap_pte(pmap, addr); 3290 if (ptep == 0) { 3291 return 0; 3292 } 3293 3294 if ((pte = *ptep) != 0) { 3295 vm_offset_t pa; 3296 3297 val = MINCORE_INCORE; 3298 if ((pte & PG_MANAGED) == 0) 3299 return val; 3300 3301 pa = pte & PG_FRAME; 3302 3303 m = PHYS_TO_VM_PAGE(pa); 3304 3305 /* 3306 * Modified by us 3307 */ 3308 if (pte & PG_M) 3309 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3310 else { 3311 /* 3312 * Modified by someone else 3313 */ 3314 vm_page_lock_queues(); 3315 if (m->dirty || pmap_is_modified(m)) 3316 val |= MINCORE_MODIFIED_OTHER; 3317 vm_page_unlock_queues(); 3318 } 3319 /* 3320 * Referenced by us 3321 */ 3322 if (pte & PG_A) 3323 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3324 else { 3325 /* 3326 * Referenced by someone else 3327 */ 3328 vm_page_lock_queues(); 3329 if ((m->flags & PG_REFERENCED) || 3330 pmap_ts_referenced(m)) { 3331 val |= MINCORE_REFERENCED_OTHER; 3332 vm_page_flag_set(m, PG_REFERENCED); 3333 } 3334 vm_page_unlock_queues(); 3335 } 3336 } 3337 return val; 3338} 3339 3340void 3341pmap_activate(struct thread *td) 3342{ 3343 struct proc *p = td->td_proc; 3344 pmap_t pmap; 3345 u_int32_t cr3; 3346 3347 pmap = vmspace_pmap(td->td_proc->p_vmspace); 3348#if defined(SMP) 3349 pmap->pm_active |= PCPU_GET(cpumask); 3350#else 3351 pmap->pm_active |= 1; 3352#endif 3353 cr3 = vtophys(pmap->pm_pdir); 3354 /* XXXKSE this is wrong. 3355 * pmap_activate is for the current thread on the current cpu 3356 */ 3357 if (p->p_flag & P_KSES) { 3358 /* Make sure all other cr3 entries are updated. */ 3359 /* what if they are running? XXXKSE (maybe abort them) */ 3360 FOREACH_THREAD_IN_PROC(p, td) { 3361 td->td_pcb->pcb_cr3 = cr3; 3362 } 3363 } else { 3364 td->td_pcb->pcb_cr3 = cr3; 3365 } 3366 load_cr3(cr3); 3367#ifdef SWTCH_OPTIM_STATS 3368 tlb_flush_count++; 3369#endif 3370} 3371 3372vm_offset_t 3373pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3374{ 3375 3376 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3377 return addr; 3378 } 3379 3380 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3381 return addr; 3382} 3383 3384 3385#if defined(PMAP_DEBUG) 3386pmap_pid_dump(int pid) 3387{ 3388 pmap_t pmap; 3389 struct proc *p; 3390 int npte = 0; 3391 int index; 3392 3393 sx_slock(&allproc_lock); 3394 LIST_FOREACH(p, &allproc, p_list) { 3395 if (p->p_pid != pid) 3396 continue; 3397 3398 if (p->p_vmspace) { 3399 int i,j; 3400 index = 0; 3401 pmap = vmspace_pmap(p->p_vmspace); 3402 for (i = 0; i < NPDEPG; i++) { 3403 pd_entry_t *pde; 3404 pt_entry_t *pte; 3405 vm_offset_t base = i << PDRSHIFT; 3406 3407 pde = &pmap->pm_pdir[i]; 3408 if (pde && pmap_pde_v(pde)) { 3409 for (j = 0; j < NPTEPG; j++) { 3410 vm_offset_t va = base + (j << PAGE_SHIFT); 3411 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3412 if (index) { 3413 index = 0; 3414 printf("\n"); 3415 } 3416 sx_sunlock(&allproc_lock); 3417 return npte; 3418 } 3419 pte = pmap_pte_quick(pmap, va); 3420 if (pte && pmap_pte_v(pte)) { 3421 pt_entry_t pa; 3422 vm_page_t m; 3423 pa = *pte; 3424 m = PHYS_TO_VM_PAGE(pa); 3425 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3426 va, pa, m->hold_count, m->wire_count, m->flags); 3427 npte++; 3428 index++; 3429 if (index >= 2) { 3430 index = 0; 3431 printf("\n"); 3432 } else { 3433 printf(" "); 3434 } 3435 } 3436 } 3437 } 3438 } 3439 } 3440 } 3441 sx_sunlock(&allproc_lock); 3442 return npte; 3443} 3444#endif 3445 3446#if defined(DEBUG) 3447 3448static void pads(pmap_t pm); 3449void pmap_pvdump(vm_offset_t pa); 3450 3451/* print address space of pmap*/ 3452static void 3453pads(pm) 3454 pmap_t pm; 3455{ 3456 int i, j; 3457 vm_offset_t va; 3458 pt_entry_t *ptep; 3459 3460 if (pm == kernel_pmap) 3461 return; 3462 for (i = 0; i < NPDEPG; i++) 3463 if (pm->pm_pdir[i]) 3464 for (j = 0; j < NPTEPG; j++) { 3465 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3466 if (pm == kernel_pmap && va < KERNBASE) 3467 continue; 3468 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3469 continue; 3470 ptep = pmap_pte_quick(pm, va); 3471 if (pmap_pte_v(ptep)) 3472 printf("%x:%x ", va, *ptep); 3473 }; 3474 3475} 3476 3477void 3478pmap_pvdump(pa) 3479 vm_offset_t pa; 3480{ 3481 pv_entry_t pv; 3482 vm_page_t m; 3483 3484 printf("pa %x", pa); 3485 m = PHYS_TO_VM_PAGE(pa); 3486 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3487 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3488 pads(pv->pv_pmap); 3489 } 3490 printf(" "); 3491} 3492#endif 3493