pmap.c revision 76827
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 76827 2001-05-19 01:28:09Z alfred $ 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_disable_pse.h" 72#include "opt_pmap.h" 73#include "opt_msgbuf.h" 74 75#include <sys/param.h> 76#include <sys/systm.h> 77#include <sys/lock.h> 78#include <sys/mutex.h> 79#include <sys/mman.h> 80#include <sys/msgbuf.h> 81#include <sys/proc.h> 82#include <sys/sx.h> 83#include <sys/user.h> 84#include <sys/vmmeter.h> 85 86#include <vm/vm.h> 87#include <vm/vm_param.h> 88#include <vm/vm_kern.h> 89#include <vm/vm_page.h> 90#include <vm/vm_map.h> 91#include <vm/vm_object.h> 92#include <vm/vm_extern.h> 93#include <vm/vm_pageout.h> 94#include <vm/vm_pager.h> 95#include <vm/vm_zone.h> 96 97#include <machine/cputypes.h> 98#include <machine/md_var.h> 99#include <machine/specialreg.h> 100#if defined(SMP) || defined(APIC_IO) 101#include <machine/smp.h> 102#include <machine/apic.h> 103#include <machine/segments.h> 104#include <machine/tss.h> 105#include <machine/globaldata.h> 106#endif /* SMP || APIC_IO */ 107 108#define PMAP_KEEP_PDIRS 109#ifndef PMAP_SHPGPERPROC 110#define PMAP_SHPGPERPROC 200 111#endif 112 113#if defined(DIAGNOSTIC) 114#define PMAP_DIAGNOSTIC 115#endif 116 117#define MINPV 2048 118 119#if !defined(PMAP_DIAGNOSTIC) 120#define PMAP_INLINE __inline 121#else 122#define PMAP_INLINE 123#endif 124 125/* 126 * Get PDEs and PTEs for user/kernel address space 127 */ 128#define pmap_pde(m, v) (&((m)->pm_pdir[(vm_offset_t)(v) >> PDRSHIFT])) 129#define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT]) 130 131#define pmap_pde_v(pte) ((*(int *)pte & PG_V) != 0) 132#define pmap_pte_w(pte) ((*(int *)pte & PG_W) != 0) 133#define pmap_pte_m(pte) ((*(int *)pte & PG_M) != 0) 134#define pmap_pte_u(pte) ((*(int *)pte & PG_A) != 0) 135#define pmap_pte_v(pte) ((*(int *)pte & PG_V) != 0) 136 137#define pmap_pte_set_w(pte, v) ((v)?(*(int *)pte |= PG_W):(*(int *)pte &= ~PG_W)) 138#define pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v))) 139 140/* 141 * Given a map and a machine independent protection code, 142 * convert to a vax protection code. 143 */ 144#define pte_prot(m, p) (protection_codes[p]) 145static int protection_codes[8]; 146 147static struct pmap kernel_pmap_store; 148pmap_t kernel_pmap; 149LIST_HEAD(pmaplist, pmap); 150struct pmaplist allpmaps; 151 152vm_offset_t avail_start; /* PA of first available physical page */ 153vm_offset_t avail_end; /* PA of last available physical page */ 154vm_offset_t virtual_avail; /* VA of first avail page (after kernel bss) */ 155vm_offset_t virtual_end; /* VA of last avail page (end of kernel AS) */ 156static boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */ 157static int pgeflag; /* PG_G or-in */ 158static int pseflag; /* PG_PS or-in */ 159 160static vm_object_t kptobj; 161 162static int nkpt; 163vm_offset_t kernel_vm_end; 164 165/* 166 * Data for the pv entry allocation mechanism 167 */ 168static vm_zone_t pvzone; 169static struct vm_zone pvzone_store; 170static struct vm_object pvzone_obj; 171static int pv_entry_count=0, pv_entry_max=0, pv_entry_high_water=0; 172static int pmap_pagedaemon_waken = 0; 173static struct pv_entry *pvinit; 174 175/* 176 * All those kernel PT submaps that BSD is so fond of 177 */ 178pt_entry_t *CMAP1 = 0; 179static pt_entry_t *CMAP2, *ptmmap; 180caddr_t CADDR1 = 0, ptvmmap = 0; 181static caddr_t CADDR2; 182static pt_entry_t *msgbufmap; 183struct msgbuf *msgbufp=0; 184 185/* 186 * Crashdump maps. 187 */ 188static pt_entry_t *pt_crashdumpmap; 189static caddr_t crashdumpmap; 190 191#ifdef SMP 192extern pt_entry_t *SMPpt; 193#endif 194static pt_entry_t *PMAP1 = 0; 195static unsigned *PADDR1 = 0; 196 197static PMAP_INLINE void free_pv_entry __P((pv_entry_t pv)); 198static unsigned * get_ptbase __P((pmap_t pmap)); 199static pv_entry_t get_pv_entry __P((void)); 200static void i386_protection_init __P((void)); 201static __inline void pmap_changebit __P((vm_page_t m, int bit, boolean_t setem)); 202 203static void pmap_remove_all __P((vm_page_t m)); 204static vm_page_t pmap_enter_quick __P((pmap_t pmap, vm_offset_t va, 205 vm_page_t m, vm_page_t mpte)); 206static int pmap_remove_pte __P((struct pmap *pmap, unsigned *ptq, 207 vm_offset_t sva)); 208static void pmap_remove_page __P((struct pmap *pmap, vm_offset_t va)); 209static int pmap_remove_entry __P((struct pmap *pmap, vm_page_t m, 210 vm_offset_t va)); 211static boolean_t pmap_testbit __P((vm_page_t m, int bit)); 212static void pmap_insert_entry __P((pmap_t pmap, vm_offset_t va, 213 vm_page_t mpte, vm_page_t m)); 214 215static vm_page_t pmap_allocpte __P((pmap_t pmap, vm_offset_t va)); 216 217static int pmap_release_free_page __P((pmap_t pmap, vm_page_t p)); 218static vm_page_t _pmap_allocpte __P((pmap_t pmap, unsigned ptepindex)); 219static unsigned * pmap_pte_quick __P((pmap_t pmap, vm_offset_t va)); 220static vm_page_t pmap_page_lookup __P((vm_object_t object, vm_pindex_t pindex)); 221static int pmap_unuse_pt __P((pmap_t, vm_offset_t, vm_page_t)); 222static vm_offset_t pmap_kmem_choose(vm_offset_t addr); 223 224static unsigned 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 unsigned * 234pmap_pte(pmap, va) 235 register pmap_t pmap; 236 vm_offset_t va; 237{ 238 unsigned *pdeaddr; 239 240 if (pmap) { 241 pdeaddr = (unsigned *) 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#ifndef DISABLE_PSE 262 if (cpu_feature & CPUID_PSE) { 263 newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 264 } 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 * The kernel's pmap is statically allocated so we don't have to use 310 * pmap_create, which is unlikely to work correctly at this part of 311 * the boot sequence (XXX and which no longer exists). 312 */ 313 kernel_pmap = &kernel_pmap_store; 314 315 kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD); 316 kernel_pmap->pm_count = 1; 317 kernel_pmap->pm_active = -1; /* don't allow deactivation */ 318 TAILQ_INIT(&kernel_pmap->pm_pvlist); 319 LIST_INIT(&allpmaps); 320 LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list); 321 nkpt = NKPT; 322 323 /* 324 * Reserve some special page table entries/VA space for temporary 325 * mapping of pages. 326 */ 327#define SYSMAP(c, p, v, n) \ 328 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n); 329 330 va = virtual_avail; 331 pte = (pt_entry_t *) pmap_pte(kernel_pmap, va); 332 333 /* 334 * CMAP1/CMAP2 are used for zeroing and copying pages. 335 */ 336 SYSMAP(caddr_t, CMAP1, CADDR1, 1) 337 SYSMAP(caddr_t, CMAP2, CADDR2, 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(unsigned *, PMAP1, PADDR1, 1); 361 362 virtual_avail = va; 363 364 *(int *) CMAP1 = *(int *) CMAP2 = 0; 365 for (i = 0; i < NKPT; i++) 366 PTD[i] = 0; 367 368 pgeflag = 0; 369#if !defined(SMP) /* XXX - see also mp_machdep.c */ 370 if (cpu_feature & CPUID_PGE) { 371 pgeflag = PG_G; 372 } 373#endif 374 375/* 376 * Initialize the 4MB page size flag 377 */ 378 pseflag = 0; 379/* 380 * The 4MB page version of the initial 381 * kernel page mapping. 382 */ 383 pdir4mb = 0; 384 385#if !defined(DISABLE_PSE) 386 if (cpu_feature & CPUID_PSE) { 387 unsigned ptditmp; 388 /* 389 * Note that we have enabled PSE mode 390 */ 391 pseflag = PG_PS; 392 ptditmp = *((unsigned *)PTmap + i386_btop(KERNBASE)); 393 ptditmp &= ~(NBPDR - 1); 394 ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag; 395 pdir4mb = ptditmp; 396 397#if !defined(SMP) 398 /* 399 * Enable the PSE mode. 400 */ 401 load_cr4(rcr4() | CR4_PSE); 402 403 /* 404 * We can do the mapping here for the single processor 405 * case. We simply ignore the old page table page from 406 * now on. 407 */ 408 /* 409 * For SMP, we still need 4K pages to bootstrap APs, 410 * PSE will be enabled as soon as all APs are up. 411 */ 412 PTD[KPTDI] = (pd_entry_t) ptditmp; 413 kernel_pmap->pm_pdir[KPTDI] = (pd_entry_t) ptditmp; 414 invltlb(); 415#endif 416 } 417#endif 418 419#ifdef SMP 420 if (cpu_apic_address == 0) 421 panic("pmap_bootstrap: no local apic! (non-SMP hardware?)"); 422 423 /* local apic is mapped on last page */ 424 SMPpt[NPTEPG - 1] = (pt_entry_t)(PG_V | PG_RW | PG_N | pgeflag | 425 (cpu_apic_address & PG_FRAME)); 426#endif 427 428 invltlb(); 429} 430 431#ifdef SMP 432/* 433 * Set 4mb pdir for mp startup 434 */ 435void 436pmap_set_opt(void) 437{ 438 if (pseflag && (cpu_feature & CPUID_PSE)) { 439 load_cr4(rcr4() | CR4_PSE); 440 if (pdir4mb && PCPU_GET(cpuid) == 0) { /* only on BSP */ 441 kernel_pmap->pm_pdir[KPTDI] = 442 PTD[KPTDI] = (pd_entry_t)pdir4mb; 443 cpu_invltlb(); 444 } 445 } 446} 447#endif 448 449/* 450 * Initialize the pmap module. 451 * Called by vm_init, to initialize any structures that the pmap 452 * system needs to map virtual memory. 453 * pmap_init has been enhanced to support in a fairly consistant 454 * way, discontiguous physical memory. 455 */ 456void 457pmap_init(phys_start, phys_end) 458 vm_offset_t phys_start, phys_end; 459{ 460 int i; 461 int initial_pvs; 462 463 /* 464 * object for kernel page table pages 465 */ 466 kptobj = vm_object_allocate(OBJT_DEFAULT, NKPDE); 467 468 /* 469 * Allocate memory for random pmap data structures. Includes the 470 * pv_head_table. 471 */ 472 473 for(i = 0; i < vm_page_array_size; i++) { 474 vm_page_t m; 475 476 m = &vm_page_array[i]; 477 TAILQ_INIT(&m->md.pv_list); 478 m->md.pv_list_count = 0; 479 } 480 481 /* 482 * init the pv free list 483 */ 484 initial_pvs = vm_page_array_size; 485 if (initial_pvs < MINPV) 486 initial_pvs = MINPV; 487 pvzone = &pvzone_store; 488 pvinit = (struct pv_entry *) kmem_alloc(kernel_map, 489 initial_pvs * sizeof (struct pv_entry)); 490 zbootinit(pvzone, "PV ENTRY", sizeof (struct pv_entry), pvinit, 491 vm_page_array_size); 492 493 /* 494 * Now it is safe to enable pv_table recording. 495 */ 496 pmap_initialized = TRUE; 497} 498 499/* 500 * Initialize the address space (zone) for the pv_entries. Set a 501 * high water mark so that the system can recover from excessive 502 * numbers of pv entries. 503 */ 504void 505pmap_init2() 506{ 507 pv_entry_max = PMAP_SHPGPERPROC * maxproc + vm_page_array_size; 508 pv_entry_high_water = 9 * (pv_entry_max / 10); 509 zinitna(pvzone, &pvzone_obj, NULL, 0, pv_entry_max, ZONE_INTERRUPT, 1); 510} 511 512 513/*************************************************** 514 * Low level helper routines..... 515 ***************************************************/ 516 517#if defined(PMAP_DIAGNOSTIC) 518 519/* 520 * This code checks for non-writeable/modified pages. 521 * This should be an invalid condition. 522 */ 523static int 524pmap_nw_modified(pt_entry_t ptea) 525{ 526 int pte; 527 528 pte = (int) ptea; 529 530 if ((pte & (PG_M|PG_RW)) == PG_M) 531 return 1; 532 else 533 return 0; 534} 535#endif 536 537 538/* 539 * this routine defines the region(s) of memory that should 540 * not be tested for the modified bit. 541 */ 542static PMAP_INLINE int 543pmap_track_modified(vm_offset_t va) 544{ 545 if ((va < clean_sva) || (va >= clean_eva)) 546 return 1; 547 else 548 return 0; 549} 550 551static PMAP_INLINE void 552invltlb_1pg(vm_offset_t va) 553{ 554#ifdef I386_CPU 555 invltlb(); 556#else 557 invlpg(va); 558#endif 559} 560 561static __inline void 562pmap_TLB_invalidate(pmap_t pmap, vm_offset_t va) 563{ 564#if defined(SMP) 565 if (pmap->pm_active & (1 << PCPU_GET(cpuid))) 566 cpu_invlpg((void *)va); 567 if (pmap->pm_active & PCPU_GET(other_cpus)) 568 smp_invltlb(); 569#else 570 if (pmap->pm_active) 571 invltlb_1pg(va); 572#endif 573} 574 575static __inline void 576pmap_TLB_invalidate_all(pmap_t pmap) 577{ 578#if defined(SMP) 579 if (pmap->pm_active & (1 << PCPU_GET(cpuid))) 580 cpu_invltlb(); 581 if (pmap->pm_active & PCPU_GET(other_cpus)) 582 smp_invltlb(); 583#else 584 if (pmap->pm_active) 585 invltlb(); 586#endif 587} 588 589static unsigned * 590get_ptbase(pmap) 591 pmap_t pmap; 592{ 593 unsigned frame = (unsigned) pmap->pm_pdir[PTDPTDI] & PG_FRAME; 594 595 /* are we current address space or kernel? */ 596 if (pmap == kernel_pmap || frame == (((unsigned) PTDpde) & PG_FRAME)) { 597 return (unsigned *) PTmap; 598 } 599 /* otherwise, we are alternate address space */ 600 if (frame != (((unsigned) APTDpde) & PG_FRAME)) { 601 APTDpde = (pd_entry_t) (frame | PG_RW | PG_V); 602#if defined(SMP) 603 /* The page directory is not shared between CPUs */ 604 cpu_invltlb(); 605#else 606 invltlb(); 607#endif 608 } 609 return (unsigned *) APTmap; 610} 611 612/* 613 * Super fast pmap_pte routine best used when scanning 614 * the pv lists. This eliminates many coarse-grained 615 * invltlb calls. Note that many of the pv list 616 * scans are across different pmaps. It is very wasteful 617 * to do an entire invltlb for checking a single mapping. 618 */ 619 620static unsigned * 621pmap_pte_quick(pmap, va) 622 register pmap_t pmap; 623 vm_offset_t va; 624{ 625 unsigned pde, newpf; 626 if ((pde = (unsigned) pmap->pm_pdir[va >> PDRSHIFT]) != 0) { 627 unsigned frame = (unsigned) pmap->pm_pdir[PTDPTDI] & PG_FRAME; 628 unsigned index = i386_btop(va); 629 /* are we current address space or kernel? */ 630 if ((pmap == kernel_pmap) || 631 (frame == (((unsigned) PTDpde) & PG_FRAME))) { 632 return (unsigned *) PTmap + index; 633 } 634 newpf = pde & PG_FRAME; 635 if ( ((* (unsigned *) PMAP1) & PG_FRAME) != newpf) { 636 * (unsigned *) PMAP1 = newpf | PG_RW | PG_V; 637 invltlb_1pg((vm_offset_t) PADDR1); 638 } 639 return PADDR1 + ((unsigned) index & (NPTEPG - 1)); 640 } 641 return (0); 642} 643 644/* 645 * Routine: pmap_extract 646 * Function: 647 * Extract the physical page address associated 648 * with the given map/virtual_address pair. 649 */ 650vm_offset_t 651pmap_extract(pmap, va) 652 register pmap_t pmap; 653 vm_offset_t va; 654{ 655 vm_offset_t rtval; 656 vm_offset_t pdirindex; 657 pdirindex = va >> PDRSHIFT; 658 if (pmap && (rtval = (unsigned) pmap->pm_pdir[pdirindex])) { 659 unsigned *pte; 660 if ((rtval & PG_PS) != 0) { 661 rtval &= ~(NBPDR - 1); 662 rtval |= va & (NBPDR - 1); 663 return rtval; 664 } 665 pte = get_ptbase(pmap) + i386_btop(va); 666 rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK)); 667 return rtval; 668 } 669 return 0; 670 671} 672 673/*************************************************** 674 * Low level mapping routines..... 675 ***************************************************/ 676 677/* 678 * add a wired page to the kva 679 * note that in order for the mapping to take effect -- you 680 * should do a invltlb after doing the pmap_kenter... 681 */ 682PMAP_INLINE void 683pmap_kenter(va, pa) 684 vm_offset_t va; 685 register vm_offset_t pa; 686{ 687 register unsigned *pte; 688 unsigned npte, opte; 689 690 npte = pa | PG_RW | PG_V | pgeflag; 691 pte = (unsigned *)vtopte(va); 692 opte = *pte; 693 *pte = npte; 694 /*if (opte)*/ 695 invltlb_1pg(va); /* XXX what about SMP? */ 696} 697 698/* 699 * remove a page from the kernel pagetables 700 */ 701PMAP_INLINE void 702pmap_kremove(va) 703 vm_offset_t va; 704{ 705 register unsigned *pte; 706 707 pte = (unsigned *)vtopte(va); 708 *pte = 0; 709 invltlb_1pg(va); /* XXX what about SMP? */ 710} 711 712/* 713 * Used to map a range of physical addresses into kernel 714 * virtual address space. 715 * 716 * The value passed in '*virt' is a suggested virtual address for 717 * the mapping. Architectures which can support a direct-mapped 718 * physical to virtual region can return the appropriate address 719 * within that region, leaving '*virt' unchanged. Other 720 * architectures should map the pages starting at '*virt' and 721 * update '*virt' with the first usable address after the mapped 722 * region. 723 */ 724vm_offset_t 725pmap_map(virt, start, end, prot) 726 vm_offset_t *virt; 727 vm_offset_t start; 728 vm_offset_t end; 729 int prot; 730{ 731 vm_offset_t sva = *virt; 732 vm_offset_t va = sva; 733 while (start < end) { 734 pmap_kenter(va, start); 735 va += PAGE_SIZE; 736 start += PAGE_SIZE; 737 } 738 *virt = va; 739 return (sva); 740} 741 742 743/* 744 * Add a list of wired pages to the kva 745 * this routine is only used for temporary 746 * kernel mappings that do not need to have 747 * page modification or references recorded. 748 * Note that old mappings are simply written 749 * over. The page *must* be wired. 750 */ 751void 752pmap_qenter(va, m, count) 753 vm_offset_t va; 754 vm_page_t *m; 755 int count; 756{ 757 int i; 758 759 for (i = 0; i < count; i++) { 760 vm_offset_t tva = va + i * PAGE_SIZE; 761 pmap_kenter(tva, VM_PAGE_TO_PHYS(m[i])); 762 } 763} 764 765/* 766 * this routine jerks page mappings from the 767 * kernel -- it is meant only for temporary mappings. 768 */ 769void 770pmap_qremove(va, count) 771 vm_offset_t va; 772 int count; 773{ 774 vm_offset_t end_va; 775 776 end_va = va + count*PAGE_SIZE; 777 778 while (va < end_va) { 779 unsigned *pte; 780 781 pte = (unsigned *)vtopte(va); 782 *pte = 0; 783#ifdef SMP 784 cpu_invlpg((void *)va); 785#else 786 invltlb_1pg(va); 787#endif 788 va += PAGE_SIZE; 789 } 790#ifdef SMP 791 smp_invltlb(); 792#endif 793} 794 795static vm_page_t 796pmap_page_lookup(object, pindex) 797 vm_object_t object; 798 vm_pindex_t pindex; 799{ 800 vm_page_t m; 801retry: 802 m = vm_page_lookup(object, pindex); 803 if (m && vm_page_sleep_busy(m, FALSE, "pplookp")) 804 goto retry; 805 return m; 806} 807 808/* 809 * Create the UPAGES for a new process. 810 * This routine directly affects the fork perf for a process. 811 */ 812void 813pmap_new_proc(p) 814 struct proc *p; 815{ 816#ifdef I386_CPU 817 int updateneeded; 818#endif 819 int i; 820 vm_object_t upobj; 821 vm_page_t m; 822 struct user *up; 823 unsigned *ptek, oldpte; 824 825 /* 826 * allocate object for the upages 827 */ 828 if ((upobj = p->p_upages_obj) == NULL) { 829 upobj = vm_object_allocate( OBJT_DEFAULT, UPAGES); 830 p->p_upages_obj = upobj; 831 } 832 833 /* get a kernel virtual address for the UPAGES for this proc */ 834 if ((up = p->p_addr) == NULL) { 835 up = (struct user *) kmem_alloc_nofault(kernel_map, 836 UPAGES * PAGE_SIZE); 837 if (up == NULL) 838 panic("pmap_new_proc: u_map allocation failed"); 839 p->p_addr = up; 840 } 841 842 ptek = (unsigned *) vtopte((vm_offset_t) up); 843 844#ifdef I386_CPU 845 updateneeded = 0; 846#endif 847 for(i=0;i<UPAGES;i++) { 848 /* 849 * Get a kernel stack page 850 */ 851 m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 852 853 /* 854 * Wire the page 855 */ 856 m->wire_count++; 857 cnt.v_wire_count++; 858 859 oldpte = *(ptek + i); 860 /* 861 * Enter the page into the kernel address space. 862 */ 863 *(ptek + i) = VM_PAGE_TO_PHYS(m) | PG_RW | PG_V | pgeflag; 864 if (oldpte) { 865#ifdef I386_CPU 866 updateneeded = 1; 867#else 868 invlpg((vm_offset_t) up + i * PAGE_SIZE); 869#endif 870 } 871 872 vm_page_wakeup(m); 873 vm_page_flag_clear(m, PG_ZERO); 874 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 875 m->valid = VM_PAGE_BITS_ALL; 876 } 877#ifdef I386_CPU 878 if (updateneeded) 879 invltlb(); 880#endif 881} 882 883/* 884 * Dispose the UPAGES for a process that has exited. 885 * This routine directly impacts the exit perf of a process. 886 */ 887void 888pmap_dispose_proc(p) 889 struct proc *p; 890{ 891 int i; 892 vm_object_t upobj; 893 vm_page_t m; 894 unsigned *ptek, oldpte; 895 896 upobj = p->p_upages_obj; 897 898 ptek = (unsigned *) vtopte((vm_offset_t) p->p_addr); 899 for(i=0;i<UPAGES;i++) { 900 901 if ((m = vm_page_lookup(upobj, i)) == NULL) 902 panic("pmap_dispose_proc: upage already missing???"); 903 904 vm_page_busy(m); 905 906 oldpte = *(ptek + i); 907 *(ptek + i) = 0; 908#ifndef I386_CPU 909 invlpg((vm_offset_t) p->p_addr + i * PAGE_SIZE); 910#endif 911 vm_page_unwire(m, 0); 912 vm_page_free(m); 913 } 914#ifdef I386_CPU 915 invltlb(); 916#endif 917} 918 919/* 920 * Allow the UPAGES for a process to be prejudicially paged out. 921 */ 922void 923pmap_swapout_proc(p) 924 struct proc *p; 925{ 926 int i; 927 vm_object_t upobj; 928 vm_page_t m; 929 930 upobj = p->p_upages_obj; 931 /* 932 * let the upages be paged 933 */ 934 for(i=0;i<UPAGES;i++) { 935 if ((m = vm_page_lookup(upobj, i)) == NULL) 936 panic("pmap_swapout_proc: upage already missing???"); 937 vm_page_dirty(m); 938 vm_page_unwire(m, 0); 939 pmap_kremove( (vm_offset_t) p->p_addr + PAGE_SIZE * i); 940 } 941} 942 943/* 944 * Bring the UPAGES for a specified process back in. 945 */ 946void 947pmap_swapin_proc(p) 948 struct proc *p; 949{ 950 int i,rv; 951 vm_object_t upobj; 952 vm_page_t m; 953 954 upobj = p->p_upages_obj; 955 for(i=0;i<UPAGES;i++) { 956 957 m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 958 959 pmap_kenter(((vm_offset_t) p->p_addr) + i * PAGE_SIZE, 960 VM_PAGE_TO_PHYS(m)); 961 962 if (m->valid != VM_PAGE_BITS_ALL) { 963 rv = vm_pager_get_pages(upobj, &m, 1, 0); 964 if (rv != VM_PAGER_OK) 965 panic("pmap_swapin_proc: cannot get upages for proc: %d\n", p->p_pid); 966 m = vm_page_lookup(upobj, i); 967 m->valid = VM_PAGE_BITS_ALL; 968 } 969 970 vm_page_wire(m); 971 vm_page_wakeup(m); 972 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 973 } 974} 975 976/*************************************************** 977 * Page table page management routines..... 978 ***************************************************/ 979 980/* 981 * This routine unholds page table pages, and if the hold count 982 * drops to zero, then it decrements the wire count. 983 */ 984static int 985_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) { 986 987 while (vm_page_sleep_busy(m, FALSE, "pmuwpt")) 988 ; 989 990 if (m->hold_count == 0) { 991 vm_offset_t pteva; 992 /* 993 * unmap the page table page 994 */ 995 pmap->pm_pdir[m->pindex] = 0; 996 --pmap->pm_stats.resident_count; 997 if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) == 998 (((unsigned) PTDpde) & PG_FRAME)) { 999 /* 1000 * Do a invltlb to make the invalidated mapping 1001 * take effect immediately. 1002 */ 1003 pteva = UPT_MIN_ADDRESS + i386_ptob(m->pindex); 1004 pmap_TLB_invalidate(pmap, pteva); 1005 } 1006 1007 if (pmap->pm_ptphint == m) 1008 pmap->pm_ptphint = NULL; 1009 1010 /* 1011 * If the page is finally unwired, simply free it. 1012 */ 1013 --m->wire_count; 1014 if (m->wire_count == 0) { 1015 1016 vm_page_flash(m); 1017 vm_page_busy(m); 1018 vm_page_free_zero(m); 1019 --cnt.v_wire_count; 1020 } 1021 return 1; 1022 } 1023 return 0; 1024} 1025 1026static PMAP_INLINE int 1027pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) 1028{ 1029 vm_page_unhold(m); 1030 if (m->hold_count == 0) 1031 return _pmap_unwire_pte_hold(pmap, m); 1032 else 1033 return 0; 1034} 1035 1036/* 1037 * After removing a page table entry, this routine is used to 1038 * conditionally free the page, and manage the hold/wire counts. 1039 */ 1040static int 1041pmap_unuse_pt(pmap, va, mpte) 1042 pmap_t pmap; 1043 vm_offset_t va; 1044 vm_page_t mpte; 1045{ 1046 unsigned ptepindex; 1047 if (va >= UPT_MIN_ADDRESS) 1048 return 0; 1049 1050 if (mpte == NULL) { 1051 ptepindex = (va >> PDRSHIFT); 1052 if (pmap->pm_ptphint && 1053 (pmap->pm_ptphint->pindex == ptepindex)) { 1054 mpte = pmap->pm_ptphint; 1055 } else { 1056 mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex); 1057 pmap->pm_ptphint = mpte; 1058 } 1059 } 1060 1061 return pmap_unwire_pte_hold(pmap, mpte); 1062} 1063 1064void 1065pmap_pinit0(pmap) 1066 struct pmap *pmap; 1067{ 1068 pmap->pm_pdir = 1069 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1070 pmap_kenter((vm_offset_t) pmap->pm_pdir, (vm_offset_t) IdlePTD); 1071 pmap->pm_count = 1; 1072 pmap->pm_active = 0; 1073 pmap->pm_ptphint = NULL; 1074 TAILQ_INIT(&pmap->pm_pvlist); 1075 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1076 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1077} 1078 1079/* 1080 * Initialize a preallocated and zeroed pmap structure, 1081 * such as one in a vmspace structure. 1082 */ 1083void 1084pmap_pinit(pmap) 1085 register struct pmap *pmap; 1086{ 1087 vm_page_t ptdpg; 1088 1089 /* 1090 * No need to allocate page table space yet but we do need a valid 1091 * page directory table. 1092 */ 1093 if (pmap->pm_pdir == NULL) 1094 pmap->pm_pdir = 1095 (pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE); 1096 1097 /* 1098 * allocate object for the ptes 1099 */ 1100 if (pmap->pm_pteobj == NULL) 1101 pmap->pm_pteobj = vm_object_allocate( OBJT_DEFAULT, PTDPTDI + 1); 1102 1103 /* 1104 * allocate the page directory page 1105 */ 1106 ptdpg = vm_page_grab( pmap->pm_pteobj, PTDPTDI, 1107 VM_ALLOC_NORMAL | VM_ALLOC_RETRY); 1108 1109 ptdpg->wire_count = 1; 1110 ++cnt.v_wire_count; 1111 1112 1113 vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/ 1114 ptdpg->valid = VM_PAGE_BITS_ALL; 1115 1116 pmap_kenter((vm_offset_t) pmap->pm_pdir, VM_PAGE_TO_PHYS(ptdpg)); 1117 if ((ptdpg->flags & PG_ZERO) == 0) 1118 bzero(pmap->pm_pdir, PAGE_SIZE); 1119 1120 LIST_INSERT_HEAD(&allpmaps, pmap, pm_list); 1121 /* Wire in kernel global address entries. */ 1122 /* XXX copies current process, does not fill in MPPTDI */ 1123 bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE); 1124#ifdef SMP 1125 pmap->pm_pdir[MPPTDI] = PTD[MPPTDI]; 1126#endif 1127 1128 /* install self-referential address mapping entry */ 1129 *(unsigned *) (pmap->pm_pdir + PTDPTDI) = 1130 VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M; 1131 1132 pmap->pm_count = 1; 1133 pmap->pm_active = 0; 1134 pmap->pm_ptphint = NULL; 1135 TAILQ_INIT(&pmap->pm_pvlist); 1136 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1137} 1138 1139/* 1140 * Wire in kernel global address entries. To avoid a race condition 1141 * between pmap initialization and pmap_growkernel, this procedure 1142 * should be called after the vmspace is attached to the process 1143 * but before this pmap is activated. 1144 */ 1145void 1146pmap_pinit2(pmap) 1147 struct pmap *pmap; 1148{ 1149 /* XXX: Remove this stub when no longer called */ 1150} 1151 1152static int 1153pmap_release_free_page(pmap, p) 1154 struct pmap *pmap; 1155 vm_page_t p; 1156{ 1157 unsigned *pde = (unsigned *) pmap->pm_pdir; 1158 /* 1159 * This code optimizes the case of freeing non-busy 1160 * page-table pages. Those pages are zero now, and 1161 * might as well be placed directly into the zero queue. 1162 */ 1163 if (vm_page_sleep_busy(p, FALSE, "pmaprl")) 1164 return 0; 1165 1166 vm_page_busy(p); 1167 1168 /* 1169 * Remove the page table page from the processes address space. 1170 */ 1171 pde[p->pindex] = 0; 1172 pmap->pm_stats.resident_count--; 1173 1174 if (p->hold_count) { 1175 panic("pmap_release: freeing held page table page"); 1176 } 1177 /* 1178 * Page directory pages need to have the kernel 1179 * stuff cleared, so they can go into the zero queue also. 1180 */ 1181 if (p->pindex == PTDPTDI) { 1182 bzero(pde + KPTDI, nkpt * PTESIZE); 1183#ifdef SMP 1184 pde[MPPTDI] = 0; 1185#endif 1186 pde[APTDPTDI] = 0; 1187 pmap_kremove((vm_offset_t) pmap->pm_pdir); 1188 } 1189 1190 if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex)) 1191 pmap->pm_ptphint = NULL; 1192 1193 p->wire_count--; 1194 cnt.v_wire_count--; 1195 vm_page_free_zero(p); 1196 return 1; 1197} 1198 1199/* 1200 * this routine is called if the page table page is not 1201 * mapped correctly. 1202 */ 1203static vm_page_t 1204_pmap_allocpte(pmap, ptepindex) 1205 pmap_t pmap; 1206 unsigned ptepindex; 1207{ 1208 vm_offset_t pteva, ptepa; 1209 vm_page_t m; 1210 1211 /* 1212 * Find or fabricate a new pagetable page 1213 */ 1214 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1215 VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1216 1217 KASSERT(m->queue == PQ_NONE, 1218 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1219 1220 if (m->wire_count == 0) 1221 cnt.v_wire_count++; 1222 m->wire_count++; 1223 1224 /* 1225 * Increment the hold count for the page table page 1226 * (denoting a new mapping.) 1227 */ 1228 m->hold_count++; 1229 1230 /* 1231 * Map the pagetable page into the process address space, if 1232 * it isn't already there. 1233 */ 1234 1235 pmap->pm_stats.resident_count++; 1236 1237 ptepa = VM_PAGE_TO_PHYS(m); 1238 pmap->pm_pdir[ptepindex] = 1239 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M); 1240 1241 /* 1242 * Set the page table hint 1243 */ 1244 pmap->pm_ptphint = m; 1245 1246 /* 1247 * Try to use the new mapping, but if we cannot, then 1248 * do it with the routine that maps the page explicitly. 1249 */ 1250 if ((m->flags & PG_ZERO) == 0) { 1251 if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) == 1252 (((unsigned) PTDpde) & PG_FRAME)) { 1253 pteva = UPT_MIN_ADDRESS + i386_ptob(ptepindex); 1254 bzero((caddr_t) pteva, PAGE_SIZE); 1255 } else { 1256 pmap_zero_page(ptepa); 1257 } 1258 } 1259 1260 m->valid = VM_PAGE_BITS_ALL; 1261 vm_page_flag_clear(m, PG_ZERO); 1262 vm_page_flag_set(m, PG_MAPPED); 1263 vm_page_wakeup(m); 1264 1265 return m; 1266} 1267 1268static vm_page_t 1269pmap_allocpte(pmap, va) 1270 pmap_t pmap; 1271 vm_offset_t va; 1272{ 1273 unsigned ptepindex; 1274 vm_offset_t ptepa; 1275 vm_page_t m; 1276 1277 /* 1278 * Calculate pagetable page index 1279 */ 1280 ptepindex = va >> PDRSHIFT; 1281 1282 /* 1283 * Get the page directory entry 1284 */ 1285 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 1286 1287 /* 1288 * This supports switching from a 4MB page to a 1289 * normal 4K page. 1290 */ 1291 if (ptepa & PG_PS) { 1292 pmap->pm_pdir[ptepindex] = 0; 1293 ptepa = 0; 1294 invltlb(); 1295 } 1296 1297 /* 1298 * If the page table page is mapped, we just increment the 1299 * hold count, and activate it. 1300 */ 1301 if (ptepa) { 1302 /* 1303 * In order to get the page table page, try the 1304 * hint first. 1305 */ 1306 if (pmap->pm_ptphint && 1307 (pmap->pm_ptphint->pindex == ptepindex)) { 1308 m = pmap->pm_ptphint; 1309 } else { 1310 m = pmap_page_lookup( pmap->pm_pteobj, ptepindex); 1311 pmap->pm_ptphint = m; 1312 } 1313 m->hold_count++; 1314 return m; 1315 } 1316 /* 1317 * Here if the pte page isn't mapped, or if it has been deallocated. 1318 */ 1319 return _pmap_allocpte(pmap, ptepindex); 1320} 1321 1322 1323/*************************************************** 1324* Pmap allocation/deallocation routines. 1325 ***************************************************/ 1326 1327/* 1328 * Release any resources held by the given physical map. 1329 * Called when a pmap initialized by pmap_pinit is being released. 1330 * Should only be called if the map contains no valid mappings. 1331 */ 1332void 1333pmap_release(pmap) 1334 register struct pmap *pmap; 1335{ 1336 vm_page_t p,n,ptdpg; 1337 vm_object_t object = pmap->pm_pteobj; 1338 int curgeneration; 1339 1340#if defined(DIAGNOSTIC) 1341 if (object->ref_count != 1) 1342 panic("pmap_release: pteobj reference count != 1"); 1343#endif 1344 1345 ptdpg = NULL; 1346 LIST_REMOVE(pmap, pm_list); 1347retry: 1348 curgeneration = object->generation; 1349 for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) { 1350 n = TAILQ_NEXT(p, listq); 1351 if (p->pindex == PTDPTDI) { 1352 ptdpg = p; 1353 continue; 1354 } 1355 while (1) { 1356 if (!pmap_release_free_page(pmap, p) && 1357 (object->generation != curgeneration)) 1358 goto retry; 1359 } 1360 } 1361 1362 if (ptdpg && !pmap_release_free_page(pmap, ptdpg)) 1363 goto retry; 1364} 1365 1366/* 1367 * grow the number of kernel page table entries, if needed 1368 */ 1369void 1370pmap_growkernel(vm_offset_t addr) 1371{ 1372 struct pmap *pmap; 1373 int s; 1374 vm_offset_t ptppaddr; 1375 vm_page_t nkpg; 1376 pd_entry_t newpdir; 1377 1378 s = splhigh(); 1379 if (kernel_vm_end == 0) { 1380 kernel_vm_end = KERNBASE; 1381 nkpt = 0; 1382 while (pdir_pde(PTD, kernel_vm_end)) { 1383 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1384 nkpt++; 1385 } 1386 } 1387 addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1388 while (kernel_vm_end < addr) { 1389 if (pdir_pde(PTD, kernel_vm_end)) { 1390 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1391 continue; 1392 } 1393 1394 /* 1395 * This index is bogus, but out of the way 1396 */ 1397 nkpg = vm_page_alloc(kptobj, nkpt, VM_ALLOC_SYSTEM); 1398 if (!nkpg) 1399 panic("pmap_growkernel: no memory to grow kernel"); 1400 1401 nkpt++; 1402 1403 vm_page_wire(nkpg); 1404 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1405 pmap_zero_page(ptppaddr); 1406 newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M); 1407 pdir_pde(PTD, kernel_vm_end) = newpdir; 1408 1409 LIST_FOREACH(pmap, &allpmaps, pm_list) { 1410 *pmap_pde(pmap, kernel_vm_end) = newpdir; 1411 } 1412 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1413 } 1414 splx(s); 1415} 1416 1417/* 1418 * Retire the given physical map from service. 1419 * Should only be called if the map contains 1420 * no valid mappings. 1421 */ 1422void 1423pmap_destroy(pmap) 1424 register pmap_t pmap; 1425{ 1426 int count; 1427 1428 if (pmap == NULL) 1429 return; 1430 1431 count = --pmap->pm_count; 1432 if (count == 0) { 1433 pmap_release(pmap); 1434 panic("destroying a pmap is not yet implemented"); 1435 } 1436} 1437 1438/* 1439 * Add a reference to the specified pmap. 1440 */ 1441void 1442pmap_reference(pmap) 1443 pmap_t pmap; 1444{ 1445 if (pmap != NULL) { 1446 pmap->pm_count++; 1447 } 1448} 1449 1450/*************************************************** 1451* page management routines. 1452 ***************************************************/ 1453 1454/* 1455 * free the pv_entry back to the free list 1456 */ 1457static PMAP_INLINE void 1458free_pv_entry(pv) 1459 pv_entry_t pv; 1460{ 1461 pv_entry_count--; 1462 zfree(pvzone, pv); 1463} 1464 1465/* 1466 * get a new pv_entry, allocating a block from the system 1467 * when needed. 1468 * the memory allocation is performed bypassing the malloc code 1469 * because of the possibility of allocations at interrupt time. 1470 */ 1471static pv_entry_t 1472get_pv_entry(void) 1473{ 1474 pv_entry_count++; 1475 if (pv_entry_high_water && 1476 (pv_entry_count > pv_entry_high_water) && 1477 (pmap_pagedaemon_waken == 0)) { 1478 pmap_pagedaemon_waken = 1; 1479 wakeup (&vm_pages_needed); 1480 } 1481 return zalloc(pvzone); 1482} 1483 1484/* 1485 * This routine is very drastic, but can save the system 1486 * in a pinch. 1487 */ 1488void 1489pmap_collect() 1490{ 1491 int i; 1492 vm_page_t m; 1493 static int warningdone=0; 1494 1495 if (pmap_pagedaemon_waken == 0) 1496 return; 1497 1498 if (warningdone < 5) { 1499 printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1500 warningdone++; 1501 } 1502 1503 for(i = 0; i < vm_page_array_size; i++) { 1504 m = &vm_page_array[i]; 1505 if (m->wire_count || m->hold_count || m->busy || 1506 (m->flags & PG_BUSY)) 1507 continue; 1508 pmap_remove_all(m); 1509 } 1510 pmap_pagedaemon_waken = 0; 1511} 1512 1513 1514/* 1515 * If it is the first entry on the list, it is actually 1516 * in the header and we must copy the following entry up 1517 * to the header. Otherwise we must search the list for 1518 * the entry. In either case we free the now unused entry. 1519 */ 1520 1521static int 1522pmap_remove_entry(pmap, m, va) 1523 struct pmap *pmap; 1524 vm_page_t m; 1525 vm_offset_t va; 1526{ 1527 pv_entry_t pv; 1528 int rtval; 1529 int s; 1530 1531 s = splvm(); 1532 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1533 for (pv = TAILQ_FIRST(&m->md.pv_list); 1534 pv; 1535 pv = TAILQ_NEXT(pv, pv_list)) { 1536 if (pmap == pv->pv_pmap && va == pv->pv_va) 1537 break; 1538 } 1539 } else { 1540 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); 1541 pv; 1542 pv = TAILQ_NEXT(pv, pv_plist)) { 1543 if (va == pv->pv_va) 1544 break; 1545 } 1546 } 1547 1548 rtval = 0; 1549 if (pv) { 1550 1551 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1552 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1553 m->md.pv_list_count--; 1554 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 1555 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1556 1557 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1558 free_pv_entry(pv); 1559 } 1560 1561 splx(s); 1562 return rtval; 1563} 1564 1565/* 1566 * Create a pv entry for page at pa for 1567 * (pmap, va). 1568 */ 1569static void 1570pmap_insert_entry(pmap, va, mpte, m) 1571 pmap_t pmap; 1572 vm_offset_t va; 1573 vm_page_t mpte; 1574 vm_page_t m; 1575{ 1576 1577 int s; 1578 pv_entry_t pv; 1579 1580 s = splvm(); 1581 pv = get_pv_entry(); 1582 pv->pv_va = va; 1583 pv->pv_pmap = pmap; 1584 pv->pv_ptem = mpte; 1585 1586 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1587 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1588 m->md.pv_list_count++; 1589 1590 splx(s); 1591} 1592 1593/* 1594 * pmap_remove_pte: do the things to unmap a page in a process 1595 */ 1596static int 1597pmap_remove_pte(pmap, ptq, va) 1598 struct pmap *pmap; 1599 unsigned *ptq; 1600 vm_offset_t va; 1601{ 1602 unsigned oldpte; 1603 vm_page_t m; 1604 1605 oldpte = atomic_readandclear_int(ptq); 1606 if (oldpte & PG_W) 1607 pmap->pm_stats.wired_count -= 1; 1608 /* 1609 * Machines that don't support invlpg, also don't support 1610 * PG_G. 1611 */ 1612 if (oldpte & PG_G) 1613 invlpg(va); 1614 pmap->pm_stats.resident_count -= 1; 1615 if (oldpte & PG_MANAGED) { 1616 m = PHYS_TO_VM_PAGE(oldpte); 1617 if (oldpte & PG_M) { 1618#if defined(PMAP_DIAGNOSTIC) 1619 if (pmap_nw_modified((pt_entry_t) oldpte)) { 1620 printf( 1621 "pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n", 1622 va, oldpte); 1623 } 1624#endif 1625 if (pmap_track_modified(va)) 1626 vm_page_dirty(m); 1627 } 1628 if (oldpte & PG_A) 1629 vm_page_flag_set(m, PG_REFERENCED); 1630 return pmap_remove_entry(pmap, m, va); 1631 } else { 1632 return pmap_unuse_pt(pmap, va, NULL); 1633 } 1634 1635 return 0; 1636} 1637 1638/* 1639 * Remove a single page from a process address space 1640 */ 1641static void 1642pmap_remove_page(pmap, va) 1643 struct pmap *pmap; 1644 register vm_offset_t va; 1645{ 1646 register unsigned *ptq; 1647 1648 /* 1649 * if there is no pte for this address, just skip it!!! 1650 */ 1651 if (*pmap_pde(pmap, va) == 0) { 1652 return; 1653 } 1654 1655 /* 1656 * get a local va for mappings for this pmap. 1657 */ 1658 ptq = get_ptbase(pmap) + i386_btop(va); 1659 if (*ptq) { 1660 (void) pmap_remove_pte(pmap, ptq, va); 1661 pmap_TLB_invalidate(pmap, va); 1662 } 1663 return; 1664} 1665 1666/* 1667 * Remove the given range of addresses from the specified map. 1668 * 1669 * It is assumed that the start and end are properly 1670 * rounded to the page size. 1671 */ 1672void 1673pmap_remove(pmap, sva, eva) 1674 struct pmap *pmap; 1675 register vm_offset_t sva; 1676 register vm_offset_t eva; 1677{ 1678 register unsigned *ptbase; 1679 vm_offset_t pdnxt; 1680 vm_offset_t ptpaddr; 1681 vm_offset_t sindex, eindex; 1682 int anyvalid; 1683 1684 if (pmap == NULL) 1685 return; 1686 1687 if (pmap->pm_stats.resident_count == 0) 1688 return; 1689 1690 /* 1691 * special handling of removing one page. a very 1692 * common operation and easy to short circuit some 1693 * code. 1694 */ 1695 if (((sva + PAGE_SIZE) == eva) && 1696 (((unsigned) pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) { 1697 pmap_remove_page(pmap, sva); 1698 return; 1699 } 1700 1701 anyvalid = 0; 1702 1703 /* 1704 * Get a local virtual address for the mappings that are being 1705 * worked with. 1706 */ 1707 ptbase = get_ptbase(pmap); 1708 1709 sindex = i386_btop(sva); 1710 eindex = i386_btop(eva); 1711 1712 for (; sindex < eindex; sindex = pdnxt) { 1713 unsigned pdirindex; 1714 1715 /* 1716 * Calculate index for next page table. 1717 */ 1718 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1719 if (pmap->pm_stats.resident_count == 0) 1720 break; 1721 1722 pdirindex = sindex / NPDEPG; 1723 if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) { 1724 pmap->pm_pdir[pdirindex] = 0; 1725 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1726 anyvalid++; 1727 continue; 1728 } 1729 1730 /* 1731 * Weed out invalid mappings. Note: we assume that the page 1732 * directory table is always allocated, and in kernel virtual. 1733 */ 1734 if (ptpaddr == 0) 1735 continue; 1736 1737 /* 1738 * Limit our scan to either the end of the va represented 1739 * by the current page table page, or to the end of the 1740 * range being removed. 1741 */ 1742 if (pdnxt > eindex) { 1743 pdnxt = eindex; 1744 } 1745 1746 for ( ;sindex != pdnxt; sindex++) { 1747 vm_offset_t va; 1748 if (ptbase[sindex] == 0) { 1749 continue; 1750 } 1751 va = i386_ptob(sindex); 1752 1753 anyvalid++; 1754 if (pmap_remove_pte(pmap, 1755 ptbase + sindex, va)) 1756 break; 1757 } 1758 } 1759 1760 if (anyvalid) 1761 pmap_TLB_invalidate_all(pmap); 1762} 1763 1764/* 1765 * Routine: pmap_remove_all 1766 * Function: 1767 * Removes this physical page from 1768 * all physical maps in which it resides. 1769 * Reflects back modify bits to the pager. 1770 * 1771 * Notes: 1772 * Original versions of this routine were very 1773 * inefficient because they iteratively called 1774 * pmap_remove (slow...) 1775 */ 1776 1777static void 1778pmap_remove_all(m) 1779 vm_page_t m; 1780{ 1781 register pv_entry_t pv; 1782 register unsigned *pte, tpte; 1783 int s; 1784 1785#if defined(PMAP_DIAGNOSTIC) 1786 /* 1787 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 1788 * pages! 1789 */ 1790 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 1791 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m)); 1792 } 1793#endif 1794 1795 s = splvm(); 1796 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 1797 pv->pv_pmap->pm_stats.resident_count--; 1798 1799 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 1800 1801 tpte = atomic_readandclear_int(pte); 1802 if (tpte & PG_W) 1803 pv->pv_pmap->pm_stats.wired_count--; 1804 1805 if (tpte & PG_A) 1806 vm_page_flag_set(m, PG_REFERENCED); 1807 1808 /* 1809 * Update the vm_page_t clean and reference bits. 1810 */ 1811 if (tpte & PG_M) { 1812#if defined(PMAP_DIAGNOSTIC) 1813 if (pmap_nw_modified((pt_entry_t) tpte)) { 1814 printf( 1815 "pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n", 1816 pv->pv_va, tpte); 1817 } 1818#endif 1819 if (pmap_track_modified(pv->pv_va)) 1820 vm_page_dirty(m); 1821 } 1822 pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va); 1823 1824 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 1825 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1826 m->md.pv_list_count--; 1827 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 1828 free_pv_entry(pv); 1829 } 1830 1831 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1832 1833 splx(s); 1834} 1835 1836/* 1837 * Set the physical protection on the 1838 * specified range of this map as requested. 1839 */ 1840void 1841pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 1842{ 1843 register unsigned *ptbase; 1844 vm_offset_t pdnxt, ptpaddr; 1845 vm_pindex_t sindex, eindex; 1846 int anychanged; 1847 1848 if (pmap == NULL) 1849 return; 1850 1851 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 1852 pmap_remove(pmap, sva, eva); 1853 return; 1854 } 1855 1856 if (prot & VM_PROT_WRITE) 1857 return; 1858 1859 anychanged = 0; 1860 1861 ptbase = get_ptbase(pmap); 1862 1863 sindex = i386_btop(sva); 1864 eindex = i386_btop(eva); 1865 1866 for (; sindex < eindex; sindex = pdnxt) { 1867 1868 unsigned pdirindex; 1869 1870 pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1)); 1871 1872 pdirindex = sindex / NPDEPG; 1873 if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) { 1874 (unsigned) pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW); 1875 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 1876 anychanged++; 1877 continue; 1878 } 1879 1880 /* 1881 * Weed out invalid mappings. Note: we assume that the page 1882 * directory table is always allocated, and in kernel virtual. 1883 */ 1884 if (ptpaddr == 0) 1885 continue; 1886 1887 if (pdnxt > eindex) { 1888 pdnxt = eindex; 1889 } 1890 1891 for (; sindex != pdnxt; sindex++) { 1892 1893 unsigned pbits; 1894 vm_page_t m; 1895 1896 pbits = ptbase[sindex]; 1897 1898 if (pbits & PG_MANAGED) { 1899 m = NULL; 1900 if (pbits & PG_A) { 1901 m = PHYS_TO_VM_PAGE(pbits); 1902 vm_page_flag_set(m, PG_REFERENCED); 1903 pbits &= ~PG_A; 1904 } 1905 if (pbits & PG_M) { 1906 if (pmap_track_modified(i386_ptob(sindex))) { 1907 if (m == NULL) 1908 m = PHYS_TO_VM_PAGE(pbits); 1909 vm_page_dirty(m); 1910 pbits &= ~PG_M; 1911 } 1912 } 1913 } 1914 1915 pbits &= ~PG_RW; 1916 1917 if (pbits != ptbase[sindex]) { 1918 ptbase[sindex] = pbits; 1919 anychanged = 1; 1920 } 1921 } 1922 } 1923 if (anychanged) 1924 pmap_TLB_invalidate_all(pmap); 1925} 1926 1927/* 1928 * Insert the given physical page (p) at 1929 * the specified virtual address (v) in the 1930 * target physical map with the protection requested. 1931 * 1932 * If specified, the page will be wired down, meaning 1933 * that the related pte can not be reclaimed. 1934 * 1935 * NB: This is the only routine which MAY NOT lazy-evaluate 1936 * or lose information. That is, this routine must actually 1937 * insert this page into the given map NOW. 1938 */ 1939void 1940pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 1941 boolean_t wired) 1942{ 1943 vm_offset_t pa; 1944 register unsigned *pte; 1945 vm_offset_t opa; 1946 vm_offset_t origpte, newpte; 1947 vm_page_t mpte; 1948 1949 if (pmap == NULL) 1950 return; 1951 1952 va &= PG_FRAME; 1953#ifdef PMAP_DIAGNOSTIC 1954 if (va > VM_MAX_KERNEL_ADDRESS) 1955 panic("pmap_enter: toobig"); 1956 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 1957 panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va); 1958#endif 1959 1960 mpte = NULL; 1961 /* 1962 * In the case that a page table page is not 1963 * resident, we are creating it here. 1964 */ 1965 if (va < UPT_MIN_ADDRESS) { 1966 mpte = pmap_allocpte(pmap, va); 1967 } 1968#if 0 && defined(PMAP_DIAGNOSTIC) 1969 else { 1970 vm_offset_t *pdeaddr = (vm_offset_t *)pmap_pde(pmap, va); 1971 if (((origpte = (vm_offset_t) *pdeaddr) & PG_V) == 0) { 1972 panic("pmap_enter: invalid kernel page table page(0), pdir=%p, pde=%p, va=%p\n", 1973 pmap->pm_pdir[PTDPTDI], origpte, va); 1974 } 1975 if (smp_active) { 1976 pdeaddr = (vm_offset_t *) IdlePTDS[PCPU_GET(cpuid)]; 1977 if (((newpte = pdeaddr[va >> PDRSHIFT]) & PG_V) == 0) { 1978 if ((vm_offset_t) my_idlePTD != (vm_offset_t) vtophys(pdeaddr)) 1979 printf("pde mismatch: %x, %x\n", my_idlePTD, pdeaddr); 1980 printf("cpuid: %d, pdeaddr: 0x%x\n", PCPU_GET(cpuid), pdeaddr); 1981 panic("pmap_enter: invalid kernel page table page(1), pdir=%p, npde=%p, pde=%p, va=%p\n", 1982 pmap->pm_pdir[PTDPTDI], newpte, origpte, va); 1983 } 1984 } 1985 } 1986#endif 1987 1988 pte = pmap_pte(pmap, va); 1989 1990 /* 1991 * Page Directory table entry not valid, we need a new PT page 1992 */ 1993 if (pte == NULL) { 1994 panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n", 1995 (void *)pmap->pm_pdir[PTDPTDI], va); 1996 } 1997 1998 pa = VM_PAGE_TO_PHYS(m) & PG_FRAME; 1999 origpte = *(vm_offset_t *)pte; 2000 opa = origpte & PG_FRAME; 2001 2002 if (origpte & PG_PS) 2003 panic("pmap_enter: attempted pmap_enter on 4MB page"); 2004 2005 /* 2006 * Mapping has not changed, must be protection or wiring change. 2007 */ 2008 if (origpte && (opa == pa)) { 2009 /* 2010 * Wiring change, just update stats. We don't worry about 2011 * wiring PT pages as they remain resident as long as there 2012 * are valid mappings in them. Hence, if a user page is wired, 2013 * the PT page will be also. 2014 */ 2015 if (wired && ((origpte & PG_W) == 0)) 2016 pmap->pm_stats.wired_count++; 2017 else if (!wired && (origpte & PG_W)) 2018 pmap->pm_stats.wired_count--; 2019 2020#if defined(PMAP_DIAGNOSTIC) 2021 if (pmap_nw_modified((pt_entry_t) origpte)) { 2022 printf( 2023 "pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n", 2024 va, origpte); 2025 } 2026#endif 2027 2028 /* 2029 * Remove extra pte reference 2030 */ 2031 if (mpte) 2032 mpte->hold_count--; 2033 2034 if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) { 2035 if ((origpte & PG_RW) == 0) { 2036 *pte |= PG_RW; 2037#ifdef SMP 2038 cpu_invlpg((void *)va); 2039 if (pmap->pm_active & PCPU_GET(other_cpus)) 2040 smp_invltlb(); 2041#else 2042 invltlb_1pg(va); 2043#endif 2044 } 2045 return; 2046 } 2047 2048 /* 2049 * We might be turning off write access to the page, 2050 * so we go ahead and sense modify status. 2051 */ 2052 if (origpte & PG_MANAGED) { 2053 if ((origpte & PG_M) && pmap_track_modified(va)) { 2054 vm_page_t om; 2055 om = PHYS_TO_VM_PAGE(opa); 2056 vm_page_dirty(om); 2057 } 2058 pa |= PG_MANAGED; 2059 } 2060 goto validate; 2061 } 2062 /* 2063 * Mapping has changed, invalidate old range and fall through to 2064 * handle validating new mapping. 2065 */ 2066 if (opa) { 2067 int err; 2068 err = pmap_remove_pte(pmap, pte, va); 2069 if (err) 2070 panic("pmap_enter: pte vanished, va: 0x%x", va); 2071 } 2072 2073 /* 2074 * Enter on the PV list if part of our managed memory. Note that we 2075 * raise IPL while manipulating pv_table since pmap_enter can be 2076 * called at interrupt time. 2077 */ 2078 if (pmap_initialized && 2079 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2080 pmap_insert_entry(pmap, va, mpte, m); 2081 pa |= PG_MANAGED; 2082 } 2083 2084 /* 2085 * Increment counters 2086 */ 2087 pmap->pm_stats.resident_count++; 2088 if (wired) 2089 pmap->pm_stats.wired_count++; 2090 2091validate: 2092 /* 2093 * Now validate mapping with desired protection/wiring. 2094 */ 2095 newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V); 2096 2097 if (wired) 2098 newpte |= PG_W; 2099 if (va < UPT_MIN_ADDRESS) 2100 newpte |= PG_U; 2101 if (pmap == kernel_pmap) 2102 newpte |= pgeflag; 2103 2104 /* 2105 * if the mapping or permission bits are different, we need 2106 * to update the pte. 2107 */ 2108 if ((origpte & ~(PG_M|PG_A)) != newpte) { 2109 *pte = newpte | PG_A; 2110 /*if (origpte)*/ { 2111#ifdef SMP 2112 cpu_invlpg((void *)va); 2113 if (pmap->pm_active & PCPU_GET(other_cpus)) 2114 smp_invltlb(); 2115#else 2116 invltlb_1pg(va); 2117#endif 2118 } 2119 } 2120} 2121 2122/* 2123 * this code makes some *MAJOR* assumptions: 2124 * 1. Current pmap & pmap exists. 2125 * 2. Not wired. 2126 * 3. Read access. 2127 * 4. No page table pages. 2128 * 5. Tlbflush is deferred to calling procedure. 2129 * 6. Page IS managed. 2130 * but is *MUCH* faster than pmap_enter... 2131 */ 2132 2133static vm_page_t 2134pmap_enter_quick(pmap, va, m, mpte) 2135 register pmap_t pmap; 2136 vm_offset_t va; 2137 vm_page_t m; 2138 vm_page_t mpte; 2139{ 2140 unsigned *pte; 2141 vm_offset_t pa; 2142 2143 /* 2144 * In the case that a page table page is not 2145 * resident, we are creating it here. 2146 */ 2147 if (va < UPT_MIN_ADDRESS) { 2148 unsigned ptepindex; 2149 vm_offset_t ptepa; 2150 2151 /* 2152 * Calculate pagetable page index 2153 */ 2154 ptepindex = va >> PDRSHIFT; 2155 if (mpte && (mpte->pindex == ptepindex)) { 2156 mpte->hold_count++; 2157 } else { 2158retry: 2159 /* 2160 * Get the page directory entry 2161 */ 2162 ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex]; 2163 2164 /* 2165 * If the page table page is mapped, we just increment 2166 * the hold count, and activate it. 2167 */ 2168 if (ptepa) { 2169 if (ptepa & PG_PS) 2170 panic("pmap_enter_quick: unexpected mapping into 4MB page"); 2171 if (pmap->pm_ptphint && 2172 (pmap->pm_ptphint->pindex == ptepindex)) { 2173 mpte = pmap->pm_ptphint; 2174 } else { 2175 mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex); 2176 pmap->pm_ptphint = mpte; 2177 } 2178 if (mpte == NULL) 2179 goto retry; 2180 mpte->hold_count++; 2181 } else { 2182 mpte = _pmap_allocpte(pmap, ptepindex); 2183 } 2184 } 2185 } else { 2186 mpte = NULL; 2187 } 2188 2189 /* 2190 * This call to vtopte makes the assumption that we are 2191 * entering the page into the current pmap. In order to support 2192 * quick entry into any pmap, one would likely use pmap_pte_quick. 2193 * But that isn't as quick as vtopte. 2194 */ 2195 pte = (unsigned *)vtopte(va); 2196 if (*pte) { 2197 if (mpte) 2198 pmap_unwire_pte_hold(pmap, mpte); 2199 return 0; 2200 } 2201 2202 /* 2203 * Enter on the PV list if part of our managed memory. Note that we 2204 * raise IPL while manipulating pv_table since pmap_enter can be 2205 * called at interrupt time. 2206 */ 2207 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) 2208 pmap_insert_entry(pmap, va, mpte, m); 2209 2210 /* 2211 * Increment counters 2212 */ 2213 pmap->pm_stats.resident_count++; 2214 2215 pa = VM_PAGE_TO_PHYS(m); 2216 2217 /* 2218 * Now validate mapping with RO protection 2219 */ 2220 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2221 *pte = pa | PG_V | PG_U; 2222 else 2223 *pte = pa | PG_V | PG_U | PG_MANAGED; 2224 2225 return mpte; 2226} 2227 2228/* 2229 * Make a temporary mapping for a physical address. This is only intended 2230 * to be used for panic dumps. 2231 */ 2232void * 2233pmap_kenter_temporary(vm_offset_t pa, int i) 2234{ 2235 pmap_kenter((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa); 2236 return ((void *)crashdumpmap); 2237} 2238 2239#define MAX_INIT_PT (96) 2240/* 2241 * pmap_object_init_pt preloads the ptes for a given object 2242 * into the specified pmap. This eliminates the blast of soft 2243 * faults on process startup and immediately after an mmap. 2244 */ 2245void 2246pmap_object_init_pt(pmap, addr, object, pindex, size, limit) 2247 pmap_t pmap; 2248 vm_offset_t addr; 2249 vm_object_t object; 2250 vm_pindex_t pindex; 2251 vm_size_t size; 2252 int limit; 2253{ 2254 vm_offset_t tmpidx; 2255 int psize; 2256 vm_page_t p, mpte; 2257 int objpgs; 2258 2259 if (pmap == NULL || object == NULL) 2260 return; 2261 2262 /* 2263 * This code maps large physical mmap regions into the 2264 * processor address space. Note that some shortcuts 2265 * are taken, but the code works. 2266 */ 2267 if (pseflag && 2268 (object->type == OBJT_DEVICE) && 2269 ((addr & (NBPDR - 1)) == 0) && 2270 ((size & (NBPDR - 1)) == 0) ) { 2271 int i; 2272 vm_page_t m[1]; 2273 unsigned int ptepindex; 2274 int npdes; 2275 vm_offset_t ptepa; 2276 2277 if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)]) 2278 return; 2279 2280retry: 2281 p = vm_page_lookup(object, pindex); 2282 if (p && vm_page_sleep_busy(p, FALSE, "init4p")) 2283 goto retry; 2284 2285 if (p == NULL) { 2286 p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL); 2287 if (p == NULL) 2288 return; 2289 m[0] = p; 2290 2291 if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) { 2292 vm_page_free(p); 2293 return; 2294 } 2295 2296 p = vm_page_lookup(object, pindex); 2297 vm_page_wakeup(p); 2298 } 2299 2300 ptepa = (vm_offset_t) VM_PAGE_TO_PHYS(p); 2301 if (ptepa & (NBPDR - 1)) { 2302 return; 2303 } 2304 2305 p->valid = VM_PAGE_BITS_ALL; 2306 2307 pmap->pm_stats.resident_count += size >> PAGE_SHIFT; 2308 npdes = size >> PDRSHIFT; 2309 for(i=0;i<npdes;i++) { 2310 pmap->pm_pdir[ptepindex] = 2311 (pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_PS); 2312 ptepa += NBPDR; 2313 ptepindex += 1; 2314 } 2315 vm_page_flag_set(p, PG_MAPPED); 2316 invltlb(); 2317 return; 2318 } 2319 2320 psize = i386_btop(size); 2321 2322 if ((object->type != OBJT_VNODE) || 2323 (limit && (psize > MAX_INIT_PT) && 2324 (object->resident_page_count > MAX_INIT_PT))) { 2325 return; 2326 } 2327 2328 if (psize + pindex > object->size) { 2329 if (object->size < pindex) 2330 return; 2331 psize = object->size - pindex; 2332 } 2333 2334 mpte = NULL; 2335 /* 2336 * if we are processing a major portion of the object, then scan the 2337 * entire thing. 2338 */ 2339 if (psize > (object->resident_page_count >> 2)) { 2340 objpgs = psize; 2341 2342 for (p = TAILQ_FIRST(&object->memq); 2343 ((objpgs > 0) && (p != NULL)); 2344 p = TAILQ_NEXT(p, listq)) { 2345 2346 tmpidx = p->pindex; 2347 if (tmpidx < pindex) { 2348 continue; 2349 } 2350 tmpidx -= pindex; 2351 if (tmpidx >= psize) { 2352 continue; 2353 } 2354 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2355 (p->busy == 0) && 2356 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2357 if ((p->queue - p->pc) == PQ_CACHE) 2358 vm_page_deactivate(p); 2359 vm_page_busy(p); 2360 mpte = pmap_enter_quick(pmap, 2361 addr + i386_ptob(tmpidx), p, mpte); 2362 vm_page_flag_set(p, PG_MAPPED); 2363 vm_page_wakeup(p); 2364 } 2365 objpgs -= 1; 2366 } 2367 } else { 2368 /* 2369 * else lookup the pages one-by-one. 2370 */ 2371 for (tmpidx = 0; tmpidx < psize; tmpidx += 1) { 2372 p = vm_page_lookup(object, tmpidx + pindex); 2373 if (p && 2374 ((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2375 (p->busy == 0) && 2376 (p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2377 if ((p->queue - p->pc) == PQ_CACHE) 2378 vm_page_deactivate(p); 2379 vm_page_busy(p); 2380 mpte = pmap_enter_quick(pmap, 2381 addr + i386_ptob(tmpidx), p, mpte); 2382 vm_page_flag_set(p, PG_MAPPED); 2383 vm_page_wakeup(p); 2384 } 2385 } 2386 } 2387 return; 2388} 2389 2390/* 2391 * pmap_prefault provides a quick way of clustering 2392 * pagefaults into a processes address space. It is a "cousin" 2393 * of pmap_object_init_pt, except it runs at page fault time instead 2394 * of mmap time. 2395 */ 2396#define PFBAK 4 2397#define PFFOR 4 2398#define PAGEORDER_SIZE (PFBAK+PFFOR) 2399 2400static int pmap_prefault_pageorder[] = { 2401 -PAGE_SIZE, PAGE_SIZE, 2402 -2 * PAGE_SIZE, 2 * PAGE_SIZE, 2403 -3 * PAGE_SIZE, 3 * PAGE_SIZE 2404 -4 * PAGE_SIZE, 4 * PAGE_SIZE 2405}; 2406 2407void 2408pmap_prefault(pmap, addra, entry) 2409 pmap_t pmap; 2410 vm_offset_t addra; 2411 vm_map_entry_t entry; 2412{ 2413 int i; 2414 vm_offset_t starta; 2415 vm_offset_t addr; 2416 vm_pindex_t pindex; 2417 vm_page_t m, mpte; 2418 vm_object_t object; 2419 2420 if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace))) 2421 return; 2422 2423 object = entry->object.vm_object; 2424 2425 starta = addra - PFBAK * PAGE_SIZE; 2426 if (starta < entry->start) { 2427 starta = entry->start; 2428 } else if (starta > addra) { 2429 starta = 0; 2430 } 2431 2432 mpte = NULL; 2433 for (i = 0; i < PAGEORDER_SIZE; i++) { 2434 vm_object_t lobject; 2435 unsigned *pte; 2436 2437 addr = addra + pmap_prefault_pageorder[i]; 2438 if (addr > addra + (PFFOR * PAGE_SIZE)) 2439 addr = 0; 2440 2441 if (addr < starta || addr >= entry->end) 2442 continue; 2443 2444 if ((*pmap_pde(pmap, addr)) == NULL) 2445 continue; 2446 2447 pte = (unsigned *) vtopte(addr); 2448 if (*pte) 2449 continue; 2450 2451 pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT; 2452 lobject = object; 2453 for (m = vm_page_lookup(lobject, pindex); 2454 (!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object)); 2455 lobject = lobject->backing_object) { 2456 if (lobject->backing_object_offset & PAGE_MASK) 2457 break; 2458 pindex += (lobject->backing_object_offset >> PAGE_SHIFT); 2459 m = vm_page_lookup(lobject->backing_object, pindex); 2460 } 2461 2462 /* 2463 * give-up when a page is not in memory 2464 */ 2465 if (m == NULL) 2466 break; 2467 2468 if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2469 (m->busy == 0) && 2470 (m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) { 2471 2472 if ((m->queue - m->pc) == PQ_CACHE) { 2473 vm_page_deactivate(m); 2474 } 2475 vm_page_busy(m); 2476 mpte = pmap_enter_quick(pmap, addr, m, mpte); 2477 vm_page_flag_set(m, PG_MAPPED); 2478 vm_page_wakeup(m); 2479 } 2480 } 2481} 2482 2483/* 2484 * Routine: pmap_change_wiring 2485 * Function: Change the wiring attribute for a map/virtual-address 2486 * pair. 2487 * In/out conditions: 2488 * The mapping must already exist in the pmap. 2489 */ 2490void 2491pmap_change_wiring(pmap, va, wired) 2492 register pmap_t pmap; 2493 vm_offset_t va; 2494 boolean_t wired; 2495{ 2496 register unsigned *pte; 2497 2498 if (pmap == NULL) 2499 return; 2500 2501 pte = pmap_pte(pmap, va); 2502 2503 if (wired && !pmap_pte_w(pte)) 2504 pmap->pm_stats.wired_count++; 2505 else if (!wired && pmap_pte_w(pte)) 2506 pmap->pm_stats.wired_count--; 2507 2508 /* 2509 * Wiring is not a hardware characteristic so there is no need to 2510 * invalidate TLB. 2511 */ 2512 pmap_pte_set_w(pte, wired); 2513} 2514 2515 2516 2517/* 2518 * Copy the range specified by src_addr/len 2519 * from the source map to the range dst_addr/len 2520 * in the destination map. 2521 * 2522 * This routine is only advisory and need not do anything. 2523 */ 2524 2525void 2526pmap_copy(dst_pmap, src_pmap, dst_addr, len, src_addr) 2527 pmap_t dst_pmap, src_pmap; 2528 vm_offset_t dst_addr; 2529 vm_size_t len; 2530 vm_offset_t src_addr; 2531{ 2532 vm_offset_t addr; 2533 vm_offset_t end_addr = src_addr + len; 2534 vm_offset_t pdnxt; 2535 unsigned src_frame, dst_frame; 2536 vm_page_t m; 2537 2538 if (dst_addr != src_addr) 2539 return; 2540 2541 src_frame = ((unsigned) src_pmap->pm_pdir[PTDPTDI]) & PG_FRAME; 2542 if (src_frame != (((unsigned) PTDpde) & PG_FRAME)) { 2543 return; 2544 } 2545 2546 dst_frame = ((unsigned) dst_pmap->pm_pdir[PTDPTDI]) & PG_FRAME; 2547 if (dst_frame != (((unsigned) APTDpde) & PG_FRAME)) { 2548 APTDpde = (pd_entry_t) (dst_frame | PG_RW | PG_V); 2549#if defined(SMP) 2550 /* The page directory is not shared between CPUs */ 2551 cpu_invltlb(); 2552#else 2553 invltlb(); 2554#endif 2555 } 2556 2557 for(addr = src_addr; addr < end_addr; addr = pdnxt) { 2558 unsigned *src_pte, *dst_pte; 2559 vm_page_t dstmpte, srcmpte; 2560 vm_offset_t srcptepaddr; 2561 unsigned ptepindex; 2562 2563 if (addr >= UPT_MIN_ADDRESS) 2564 panic("pmap_copy: invalid to pmap_copy page tables\n"); 2565 2566 /* 2567 * Don't let optional prefaulting of pages make us go 2568 * way below the low water mark of free pages or way 2569 * above high water mark of used pv entries. 2570 */ 2571 if (cnt.v_free_count < cnt.v_free_reserved || 2572 pv_entry_count > pv_entry_high_water) 2573 break; 2574 2575 pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1)); 2576 ptepindex = addr >> PDRSHIFT; 2577 2578 srcptepaddr = (vm_offset_t) src_pmap->pm_pdir[ptepindex]; 2579 if (srcptepaddr == 0) 2580 continue; 2581 2582 if (srcptepaddr & PG_PS) { 2583 if (dst_pmap->pm_pdir[ptepindex] == 0) { 2584 dst_pmap->pm_pdir[ptepindex] = (pd_entry_t) srcptepaddr; 2585 dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE; 2586 } 2587 continue; 2588 } 2589 2590 srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex); 2591 if ((srcmpte == NULL) || 2592 (srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY)) 2593 continue; 2594 2595 if (pdnxt > end_addr) 2596 pdnxt = end_addr; 2597 2598 src_pte = (unsigned *) vtopte(addr); 2599 dst_pte = (unsigned *) avtopte(addr); 2600 while (addr < pdnxt) { 2601 unsigned ptetemp; 2602 ptetemp = *src_pte; 2603 /* 2604 * we only virtual copy managed pages 2605 */ 2606 if ((ptetemp & PG_MANAGED) != 0) { 2607 /* 2608 * We have to check after allocpte for the 2609 * pte still being around... allocpte can 2610 * block. 2611 */ 2612 dstmpte = pmap_allocpte(dst_pmap, addr); 2613 if ((*dst_pte == 0) && (ptetemp = *src_pte)) { 2614 /* 2615 * Clear the modified and 2616 * accessed (referenced) bits 2617 * during the copy. 2618 */ 2619 m = PHYS_TO_VM_PAGE(ptetemp); 2620 *dst_pte = ptetemp & ~(PG_M | PG_A); 2621 dst_pmap->pm_stats.resident_count++; 2622 pmap_insert_entry(dst_pmap, addr, 2623 dstmpte, m); 2624 } else { 2625 pmap_unwire_pte_hold(dst_pmap, dstmpte); 2626 } 2627 if (dstmpte->hold_count >= srcmpte->hold_count) 2628 break; 2629 } 2630 addr += PAGE_SIZE; 2631 src_pte++; 2632 dst_pte++; 2633 } 2634 } 2635} 2636 2637/* 2638 * Routine: pmap_kernel 2639 * Function: 2640 * Returns the physical map handle for the kernel. 2641 */ 2642pmap_t 2643pmap_kernel() 2644{ 2645 return (kernel_pmap); 2646} 2647 2648/* 2649 * pmap_zero_page zeros the specified hardware page by mapping 2650 * the page into KVM and using bzero to clear its contents. 2651 */ 2652void 2653pmap_zero_page(phys) 2654 vm_offset_t phys; 2655{ 2656 2657 if (*(int *) CMAP2) 2658 panic("pmap_zero_page: CMAP2 busy"); 2659 2660 *(int *) CMAP2 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M; 2661 invltlb_1pg((vm_offset_t)CADDR2); 2662 2663#if defined(I686_CPU) 2664 if (cpu_class == CPUCLASS_686) 2665 i686_pagezero(CADDR2); 2666 else 2667#endif 2668 bzero(CADDR2, PAGE_SIZE); 2669 *(int *) CMAP2 = 0; 2670} 2671 2672/* 2673 * pmap_zero_page_area zeros the specified hardware page by mapping 2674 * the page into KVM and using bzero to clear its contents. 2675 * 2676 * off and size may not cover an area beyond a single hardware page. 2677 */ 2678void 2679pmap_zero_page_area(phys, off, size) 2680 vm_offset_t phys; 2681 int off; 2682 int size; 2683{ 2684 2685 if (*(int *) CMAP2) 2686 panic("pmap_zero_page: CMAP2 busy"); 2687 2688 *(int *) CMAP2 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M; 2689 invltlb_1pg((vm_offset_t)CADDR2); 2690 2691#if defined(I686_CPU) 2692 if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE) 2693 i686_pagezero(CADDR2); 2694 else 2695#endif 2696 bzero((char *)CADDR2 + off, size); 2697 *(int *) CMAP2 = 0; 2698} 2699 2700/* 2701 * pmap_copy_page copies the specified (machine independent) 2702 * page by mapping the page into virtual memory and using 2703 * bcopy to copy the page, one machine dependent page at a 2704 * time. 2705 */ 2706void 2707pmap_copy_page(src, dst) 2708 vm_offset_t src; 2709 vm_offset_t dst; 2710{ 2711 2712 if (*(int *) CMAP1) 2713 panic("pmap_copy_page: CMAP1 busy"); 2714 if (*(int *) CMAP2) 2715 panic("pmap_copy_page: CMAP2 busy"); 2716 2717 *(int *) CMAP1 = PG_V | (src & PG_FRAME) | PG_A; 2718 *(int *) CMAP2 = PG_V | PG_RW | (dst & PG_FRAME) | PG_A | PG_M; 2719#ifdef I386_CPU 2720 invltlb(); 2721#else 2722 invlpg((u_int)CADDR1); 2723 invlpg((u_int)CADDR2); 2724#endif 2725 2726 bcopy(CADDR1, CADDR2, PAGE_SIZE); 2727 2728 *(int *) CMAP1 = 0; 2729 *(int *) CMAP2 = 0; 2730} 2731 2732 2733/* 2734 * Routine: pmap_pageable 2735 * Function: 2736 * Make the specified pages (by pmap, offset) 2737 * pageable (or not) as requested. 2738 * 2739 * A page which is not pageable may not take 2740 * a fault; therefore, its page table entry 2741 * must remain valid for the duration. 2742 * 2743 * This routine is merely advisory; pmap_enter 2744 * will specify that these pages are to be wired 2745 * down (or not) as appropriate. 2746 */ 2747void 2748pmap_pageable(pmap, sva, eva, pageable) 2749 pmap_t pmap; 2750 vm_offset_t sva, eva; 2751 boolean_t pageable; 2752{ 2753} 2754 2755/* 2756 * this routine returns true if a physical page resides 2757 * in the given pmap. 2758 */ 2759boolean_t 2760pmap_page_exists(pmap, m) 2761 pmap_t pmap; 2762 vm_page_t m; 2763{ 2764 register pv_entry_t pv; 2765 int s; 2766 2767 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2768 return FALSE; 2769 2770 s = splvm(); 2771 2772 /* 2773 * Not found, check current mappings returning immediately if found. 2774 */ 2775 for (pv = TAILQ_FIRST(&m->md.pv_list); 2776 pv; 2777 pv = TAILQ_NEXT(pv, pv_list)) { 2778 if (pv->pv_pmap == pmap) { 2779 splx(s); 2780 return TRUE; 2781 } 2782 } 2783 splx(s); 2784 return (FALSE); 2785} 2786 2787#define PMAP_REMOVE_PAGES_CURPROC_ONLY 2788/* 2789 * Remove all pages from specified address space 2790 * this aids process exit speeds. Also, this code 2791 * is special cased for current process only, but 2792 * can have the more generic (and slightly slower) 2793 * mode enabled. This is much faster than pmap_remove 2794 * in the case of running down an entire address space. 2795 */ 2796void 2797pmap_remove_pages(pmap, sva, eva) 2798 pmap_t pmap; 2799 vm_offset_t sva, eva; 2800{ 2801 unsigned *pte, tpte; 2802 pv_entry_t pv, npv; 2803 int s; 2804 vm_page_t m; 2805 2806#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2807 if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace))) { 2808 printf("warning: pmap_remove_pages called with non-current pmap\n"); 2809 return; 2810 } 2811#endif 2812 2813 s = splvm(); 2814 for(pv = TAILQ_FIRST(&pmap->pm_pvlist); 2815 pv; 2816 pv = npv) { 2817 2818 if (pv->pv_va >= eva || pv->pv_va < sva) { 2819 npv = TAILQ_NEXT(pv, pv_plist); 2820 continue; 2821 } 2822 2823#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY 2824 pte = (unsigned *)vtopte(pv->pv_va); 2825#else 2826 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2827#endif 2828 tpte = *pte; 2829 2830/* 2831 * We cannot remove wired pages from a process' mapping at this time 2832 */ 2833 if (tpte & PG_W) { 2834 npv = TAILQ_NEXT(pv, pv_plist); 2835 continue; 2836 } 2837 *pte = 0; 2838 2839 m = PHYS_TO_VM_PAGE(tpte); 2840 2841 KASSERT(m < &vm_page_array[vm_page_array_size], 2842 ("pmap_remove_pages: bad tpte %x", tpte)); 2843 2844 pv->pv_pmap->pm_stats.resident_count--; 2845 2846 /* 2847 * Update the vm_page_t clean and reference bits. 2848 */ 2849 if (tpte & PG_M) { 2850 vm_page_dirty(m); 2851 } 2852 2853 2854 npv = TAILQ_NEXT(pv, pv_plist); 2855 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 2856 2857 m->md.pv_list_count--; 2858 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 2859 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 2860 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 2861 } 2862 2863 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 2864 free_pv_entry(pv); 2865 } 2866 splx(s); 2867 pmap_TLB_invalidate_all(pmap); 2868} 2869 2870/* 2871 * pmap_testbit tests bits in pte's 2872 * note that the testbit/changebit routines are inline, 2873 * and a lot of things compile-time evaluate. 2874 */ 2875static boolean_t 2876pmap_testbit(m, bit) 2877 vm_page_t m; 2878 int bit; 2879{ 2880 pv_entry_t pv; 2881 unsigned *pte; 2882 int s; 2883 2884 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2885 return FALSE; 2886 2887 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 2888 return FALSE; 2889 2890 s = splvm(); 2891 2892 for (pv = TAILQ_FIRST(&m->md.pv_list); 2893 pv; 2894 pv = TAILQ_NEXT(pv, pv_list)) { 2895 2896 /* 2897 * if the bit being tested is the modified bit, then 2898 * mark clean_map and ptes as never 2899 * modified. 2900 */ 2901 if (bit & (PG_A|PG_M)) { 2902 if (!pmap_track_modified(pv->pv_va)) 2903 continue; 2904 } 2905 2906#if defined(PMAP_DIAGNOSTIC) 2907 if (!pv->pv_pmap) { 2908 printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va); 2909 continue; 2910 } 2911#endif 2912 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2913 if (*pte & bit) { 2914 splx(s); 2915 return TRUE; 2916 } 2917 } 2918 splx(s); 2919 return (FALSE); 2920} 2921 2922/* 2923 * this routine is used to modify bits in ptes 2924 */ 2925static __inline void 2926pmap_changebit(m, bit, setem) 2927 vm_page_t m; 2928 int bit; 2929 boolean_t setem; 2930{ 2931 register pv_entry_t pv; 2932 register unsigned *pte; 2933 int s; 2934 2935 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2936 return; 2937 2938 s = splvm(); 2939 2940 /* 2941 * Loop over all current mappings setting/clearing as appropos If 2942 * setting RO do we need to clear the VAC? 2943 */ 2944 for (pv = TAILQ_FIRST(&m->md.pv_list); 2945 pv; 2946 pv = TAILQ_NEXT(pv, pv_list)) { 2947 2948 /* 2949 * don't write protect pager mappings 2950 */ 2951 if (!setem && (bit == PG_RW)) { 2952 if (!pmap_track_modified(pv->pv_va)) 2953 continue; 2954 } 2955 2956#if defined(PMAP_DIAGNOSTIC) 2957 if (!pv->pv_pmap) { 2958 printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va); 2959 continue; 2960 } 2961#endif 2962 2963 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 2964 2965 if (setem) { 2966 *(int *)pte |= bit; 2967 pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va); 2968 } else { 2969 vm_offset_t pbits = *(vm_offset_t *)pte; 2970 if (pbits & bit) { 2971 if (bit == PG_RW) { 2972 if (pbits & PG_M) { 2973 vm_page_dirty(m); 2974 } 2975 *(int *)pte = pbits & ~(PG_M|PG_RW); 2976 } else { 2977 *(int *)pte = pbits & ~bit; 2978 } 2979 pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va); 2980 } 2981 } 2982 } 2983 splx(s); 2984} 2985 2986/* 2987 * pmap_page_protect: 2988 * 2989 * Lower the permission for all mappings to a given page. 2990 */ 2991void 2992pmap_page_protect(vm_page_t m, vm_prot_t prot) 2993{ 2994 if ((prot & VM_PROT_WRITE) == 0) { 2995 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 2996 pmap_changebit(m, PG_RW, FALSE); 2997 } else { 2998 pmap_remove_all(m); 2999 } 3000 } 3001} 3002 3003vm_offset_t 3004pmap_phys_address(ppn) 3005 int ppn; 3006{ 3007 return (i386_ptob(ppn)); 3008} 3009 3010/* 3011 * pmap_ts_referenced: 3012 * 3013 * Return the count of reference bits for a page, clearing all of them. 3014 */ 3015int 3016pmap_ts_referenced(vm_page_t m) 3017{ 3018 register pv_entry_t pv, pvf, pvn; 3019 unsigned *pte; 3020 int s; 3021 int rtval = 0; 3022 3023 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3024 return (rtval); 3025 3026 s = splvm(); 3027 3028 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3029 3030 pvf = pv; 3031 3032 do { 3033 pvn = TAILQ_NEXT(pv, pv_list); 3034 3035 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3036 3037 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3038 3039 if (!pmap_track_modified(pv->pv_va)) 3040 continue; 3041 3042 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va); 3043 3044 if (pte && (*pte & PG_A)) { 3045 *pte &= ~PG_A; 3046 3047 pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va); 3048 3049 rtval++; 3050 if (rtval > 4) { 3051 break; 3052 } 3053 } 3054 } while ((pv = pvn) != NULL && pv != pvf); 3055 } 3056 splx(s); 3057 3058 return (rtval); 3059} 3060 3061/* 3062 * pmap_is_modified: 3063 * 3064 * Return whether or not the specified physical page was modified 3065 * in any physical maps. 3066 */ 3067boolean_t 3068pmap_is_modified(vm_page_t m) 3069{ 3070 return pmap_testbit(m, PG_M); 3071} 3072 3073/* 3074 * Clear the modify bits on the specified physical page. 3075 */ 3076void 3077pmap_clear_modify(vm_page_t m) 3078{ 3079 pmap_changebit(m, PG_M, FALSE); 3080} 3081 3082/* 3083 * pmap_clear_reference: 3084 * 3085 * Clear the reference bit on the specified physical page. 3086 */ 3087void 3088pmap_clear_reference(vm_page_t m) 3089{ 3090 pmap_changebit(m, PG_A, FALSE); 3091} 3092 3093/* 3094 * Miscellaneous support routines follow 3095 */ 3096 3097static void 3098i386_protection_init() 3099{ 3100 register int *kp, prot; 3101 3102 kp = protection_codes; 3103 for (prot = 0; prot < 8; prot++) { 3104 switch (prot) { 3105 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 3106 /* 3107 * Read access is also 0. There isn't any execute bit, 3108 * so just make it readable. 3109 */ 3110 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 3111 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 3112 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 3113 *kp++ = 0; 3114 break; 3115 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 3116 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 3117 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 3118 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 3119 *kp++ = PG_RW; 3120 break; 3121 } 3122 } 3123} 3124 3125/* 3126 * Map a set of physical memory pages into the kernel virtual 3127 * address space. Return a pointer to where it is mapped. This 3128 * routine is intended to be used for mapping device memory, 3129 * NOT real memory. 3130 */ 3131void * 3132pmap_mapdev(pa, size) 3133 vm_offset_t pa; 3134 vm_size_t size; 3135{ 3136 vm_offset_t va, tmpva, offset; 3137 unsigned *pte; 3138 3139 offset = pa & PAGE_MASK; 3140 size = roundup(offset + size, PAGE_SIZE); 3141 3142 va = kmem_alloc_pageable(kernel_map, size); 3143 if (!va) 3144 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 3145 3146 pa = pa & PG_FRAME; 3147 for (tmpva = va; size > 0;) { 3148 pte = (unsigned *)vtopte(tmpva); 3149 *pte = pa | PG_RW | PG_V | pgeflag; 3150 size -= PAGE_SIZE; 3151 tmpva += PAGE_SIZE; 3152 pa += PAGE_SIZE; 3153 } 3154 invltlb(); 3155 3156 return ((void *)(va + offset)); 3157} 3158 3159void 3160pmap_unmapdev(va, size) 3161 vm_offset_t va; 3162 vm_size_t size; 3163{ 3164 vm_offset_t base, offset; 3165 3166 base = va & PG_FRAME; 3167 offset = va & PAGE_MASK; 3168 size = roundup(offset + size, PAGE_SIZE); 3169 kmem_free(kernel_map, base, size); 3170} 3171 3172/* 3173 * perform the pmap work for mincore 3174 */ 3175int 3176pmap_mincore(pmap, addr) 3177 pmap_t pmap; 3178 vm_offset_t addr; 3179{ 3180 3181 unsigned *ptep, pte; 3182 vm_page_t m; 3183 int val = 0; 3184 3185 ptep = pmap_pte(pmap, addr); 3186 if (ptep == 0) { 3187 return 0; 3188 } 3189 3190 if ((pte = *ptep) != 0) { 3191 vm_offset_t pa; 3192 3193 val = MINCORE_INCORE; 3194 if ((pte & PG_MANAGED) == 0) 3195 return val; 3196 3197 pa = pte & PG_FRAME; 3198 3199 m = PHYS_TO_VM_PAGE(pa); 3200 3201 /* 3202 * Modified by us 3203 */ 3204 if (pte & PG_M) 3205 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3206 /* 3207 * Modified by someone 3208 */ 3209 else if (m->dirty || pmap_is_modified(m)) 3210 val |= MINCORE_MODIFIED_OTHER; 3211 /* 3212 * Referenced by us 3213 */ 3214 if (pte & PG_A) 3215 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3216 3217 /* 3218 * Referenced by someone 3219 */ 3220 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3221 val |= MINCORE_REFERENCED_OTHER; 3222 vm_page_flag_set(m, PG_REFERENCED); 3223 } 3224 } 3225 return val; 3226} 3227 3228void 3229pmap_activate(struct proc *p) 3230{ 3231 pmap_t pmap; 3232 3233 pmap = vmspace_pmap(p->p_vmspace); 3234#if defined(SMP) 3235 pmap->pm_active |= 1 << PCPU_GET(cpuid); 3236#else 3237 pmap->pm_active |= 1; 3238#endif 3239#if defined(SWTCH_OPTIM_STATS) 3240 tlb_flush_count++; 3241#endif 3242 load_cr3(p->p_addr->u_pcb.pcb_cr3 = vtophys(pmap->pm_pdir)); 3243} 3244 3245vm_offset_t 3246pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3247{ 3248 3249 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3250 return addr; 3251 } 3252 3253 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3254 return addr; 3255} 3256 3257 3258#if defined(PMAP_DEBUG) 3259pmap_pid_dump(int pid) 3260{ 3261 pmap_t pmap; 3262 struct proc *p; 3263 int npte = 0; 3264 int index; 3265 3266 sx_slock(&allproc_lock); 3267 LIST_FOREACH(p, &allproc, p_list) { 3268 if (p->p_pid != pid) 3269 continue; 3270 3271 if (p->p_vmspace) { 3272 int i,j; 3273 index = 0; 3274 pmap = vmspace_pmap(p->p_vmspace); 3275 for(i=0;i<1024;i++) { 3276 pd_entry_t *pde; 3277 unsigned *pte; 3278 unsigned base = i << PDRSHIFT; 3279 3280 pde = &pmap->pm_pdir[i]; 3281 if (pde && pmap_pde_v(pde)) { 3282 for(j=0;j<1024;j++) { 3283 unsigned va = base + (j << PAGE_SHIFT); 3284 if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) { 3285 if (index) { 3286 index = 0; 3287 printf("\n"); 3288 } 3289 sx_sunlock(&allproc_lock); 3290 return npte; 3291 } 3292 pte = pmap_pte_quick( pmap, va); 3293 if (pte && pmap_pte_v(pte)) { 3294 vm_offset_t pa; 3295 vm_page_t m; 3296 pa = *(int *)pte; 3297 m = PHYS_TO_VM_PAGE(pa); 3298 printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x", 3299 va, pa, m->hold_count, m->wire_count, m->flags); 3300 npte++; 3301 index++; 3302 if (index >= 2) { 3303 index = 0; 3304 printf("\n"); 3305 } else { 3306 printf(" "); 3307 } 3308 } 3309 } 3310 } 3311 } 3312 } 3313 } 3314 sx_sunlock(&allproc_lock); 3315 return npte; 3316} 3317#endif 3318 3319#if defined(DEBUG) 3320 3321static void pads __P((pmap_t pm)); 3322void pmap_pvdump __P((vm_offset_t pa)); 3323 3324/* print address space of pmap*/ 3325static void 3326pads(pm) 3327 pmap_t pm; 3328{ 3329 unsigned va, i, j; 3330 unsigned *ptep; 3331 3332 if (pm == kernel_pmap) 3333 return; 3334 for (i = 0; i < 1024; i++) 3335 if (pm->pm_pdir[i]) 3336 for (j = 0; j < 1024; j++) { 3337 va = (i << PDRSHIFT) + (j << PAGE_SHIFT); 3338 if (pm == kernel_pmap && va < KERNBASE) 3339 continue; 3340 if (pm != kernel_pmap && va > UPT_MAX_ADDRESS) 3341 continue; 3342 ptep = pmap_pte_quick(pm, va); 3343 if (pmap_pte_v(ptep)) 3344 printf("%x:%x ", va, *(int *) ptep); 3345 }; 3346 3347} 3348 3349void 3350pmap_pvdump(pa) 3351 vm_offset_t pa; 3352{ 3353 register pv_entry_t pv; 3354 vm_page_t m; 3355 3356 printf("pa %x", pa); 3357 m = PHYS_TO_VM_PAGE(pa); 3358 for (pv = TAILQ_FIRST(&m->md.pv_list); 3359 pv; 3360 pv = TAILQ_NEXT(pv, pv_list)) { 3361#ifdef used_to_be 3362 printf(" -> pmap %p, va %x, flags %x", 3363 (void *)pv->pv_pmap, pv->pv_va, pv->pv_flags); 3364#endif 3365 printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va); 3366 pads(pv->pv_pmap); 3367 } 3368 printf(" "); 3369} 3370#endif 3371