1 /* 2 * (MPSAFE) 3 * 4 * Copyright (c) 1991 Regents of the University of California. 5 * Copyright (c) 1994 John S. Dyson 6 * Copyright (c) 1994 David Greenman 7 * Copyright (c) 2003 Peter Wemm 8 * Copyright (c) 2005-2008 Alan L. Cox <alc@cs.rice.edu> 9 * Copyright (c) 2008, 2009 The DragonFly Project. 10 * Copyright (c) 2008, 2009 Jordan Gordeev. 11 * All rights reserved. 12 * 13 * This code is derived from software contributed to Berkeley by 14 * the Systems Programming Group of the University of Utah Computer 15 * Science Department and William Jolitz of UUNET Technologies Inc. 16 * 17 * Redistribution and use in source and binary forms, with or without 18 * modification, are permitted provided that the following conditions 19 * are met: 20 * 1. Redistributions of source code must retain the above copyright 21 * notice, this list of conditions and the following disclaimer. 22 * 2. Redistributions in binary form must reproduce the above copyright 23 * notice, this list of conditions and the following disclaimer in the 24 * documentation and/or other materials provided with the distribution. 25 * 3. All advertising materials mentioning features or use of this software 26 * must display the following acknowledgement: 27 * This product includes software developed by the University of 28 * California, Berkeley and its contributors. 29 * 4. Neither the name of the University nor the names of its contributors 30 * may be used to endorse or promote products derived from this software 31 * without specific prior written permission. 32 * 33 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 34 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 35 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 36 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 37 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 38 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 39 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 40 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 41 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 42 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 43 * SUCH DAMAGE. 44 * 45 * from: @(#)pmap.c 7.7 (Berkeley) 5/12/91 46 * $FreeBSD: src/sys/i386/i386/pmap.c,v 1.250.2.18 2002/03/06 22:48:53 silby Exp $ 47 */ 48 49 /* 50 * Manages physical address maps. 51 */ 52 53 #if JG 54 #include "opt_pmap.h" 55 #endif 56 #include "opt_msgbuf.h" 57 58 #include <sys/param.h> 59 #include <sys/systm.h> 60 #include <sys/kernel.h> 61 #include <sys/proc.h> 62 #include <sys/msgbuf.h> 63 #include <sys/vmmeter.h> 64 #include <sys/mman.h> 65 #include <sys/vmspace.h> 66 67 #include <vm/vm.h> 68 #include <vm/vm_param.h> 69 #include <sys/sysctl.h> 70 #include <sys/lock.h> 71 #include <vm/vm_kern.h> 72 #include <vm/vm_page.h> 73 #include <vm/vm_map.h> 74 #include <vm/vm_object.h> 75 #include <vm/vm_extern.h> 76 #include <vm/vm_pageout.h> 77 #include <vm/vm_pager.h> 78 #include <vm/vm_zone.h> 79 80 #include <sys/user.h> 81 #include <sys/thread2.h> 82 #include <sys/sysref2.h> 83 #include <sys/spinlock2.h> 84 #include <vm/vm_page2.h> 85 86 #include <machine/cputypes.h> 87 #include <machine/md_var.h> 88 #include <machine/specialreg.h> 89 #include <machine/smp.h> 90 #include <machine/globaldata.h> 91 #include <machine/pmap.h> 92 #include <machine/pmap_inval.h> 93 94 #include <ddb/ddb.h> 95 96 #include <stdio.h> 97 #include <assert.h> 98 #include <stdlib.h> 99 #include <pthread.h> 100 101 #define PMAP_KEEP_PDIRS 102 #ifndef PMAP_SHPGPERPROC 103 #define PMAP_SHPGPERPROC 1000 104 #endif 105 106 #if defined(DIAGNOSTIC) 107 #define PMAP_DIAGNOSTIC 108 #endif 109 110 #define MINPV 2048 111 112 #if !defined(PMAP_DIAGNOSTIC) 113 #define PMAP_INLINE __inline 114 #else 115 #define PMAP_INLINE 116 #endif 117 118 /* 119 * Get PDEs and PTEs for user/kernel address space 120 */ 121 static pd_entry_t *pmap_pde(pmap_t pmap, vm_offset_t va); 122 #define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT]) 123 124 #define pmap_pde_v(pte) ((*(pd_entry_t *)pte & VPTE_V) != 0) 125 #define pmap_pte_w(pte) ((*(pt_entry_t *)pte & VPTE_WIRED) != 0) 126 #define pmap_pte_m(pte) ((*(pt_entry_t *)pte & VPTE_M) != 0) 127 #define pmap_pte_u(pte) ((*(pt_entry_t *)pte & VPTE_A) != 0) 128 #define pmap_pte_v(pte) ((*(pt_entry_t *)pte & VPTE_V) != 0) 129 130 /* 131 * Given a map and a machine independent protection code, 132 * convert to a vax protection code. 133 */ 134 #define pte_prot(m, p) \ 135 (protection_codes[p & (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE)]) 136 static int protection_codes[8]; 137 138 struct pmap kernel_pmap; 139 static TAILQ_HEAD(,pmap) pmap_list = TAILQ_HEAD_INITIALIZER(pmap_list); 140 141 static boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */ 142 143 static vm_object_t kptobj; 144 145 static int nkpt; 146 147 static uint64_t KPDphys; /* phys addr of kernel level 2 */ 148 uint64_t KPDPphys; /* phys addr of kernel level 3 */ 149 uint64_t KPML4phys; /* phys addr of kernel level 4 */ 150 151 extern int vmm_enabled; 152 extern void *vkernel_stack; 153 154 /* 155 * Data for the pv entry allocation mechanism 156 */ 157 static vm_zone_t pvzone; 158 static struct vm_zone pvzone_store; 159 static struct vm_object pvzone_obj; 160 static int pv_entry_count=0, pv_entry_max=0, pv_entry_high_water=0; 161 static int pmap_pagedaemon_waken = 0; 162 static struct pv_entry *pvinit; 163 164 /* 165 * All those kernel PT submaps that BSD is so fond of 166 */ 167 pt_entry_t *CMAP1 = NULL, *ptmmap; 168 caddr_t CADDR1 = NULL; 169 static pt_entry_t *msgbufmap; 170 171 uint64_t KPTphys; 172 173 static PMAP_INLINE void free_pv_entry (pv_entry_t pv); 174 static pv_entry_t get_pv_entry (void); 175 static void i386_protection_init (void); 176 static __inline void pmap_clearbit (vm_page_t m, int bit); 177 178 static void pmap_remove_all (vm_page_t m); 179 static int pmap_remove_pte (struct pmap *pmap, pt_entry_t *ptq, 180 vm_offset_t sva); 181 static void pmap_remove_page (struct pmap *pmap, vm_offset_t va); 182 static int pmap_remove_entry (struct pmap *pmap, vm_page_t m, 183 vm_offset_t va); 184 static boolean_t pmap_testbit (vm_page_t m, int bit); 185 static void pmap_insert_entry (pmap_t pmap, vm_offset_t va, 186 vm_page_t mpte, vm_page_t m); 187 188 static vm_page_t pmap_allocpte (pmap_t pmap, vm_offset_t va); 189 190 static int pmap_release_free_page (pmap_t pmap, vm_page_t p); 191 static vm_page_t _pmap_allocpte (pmap_t pmap, vm_pindex_t ptepindex); 192 #if JGPMAP32 193 static pt_entry_t * pmap_pte_quick (pmap_t pmap, vm_offset_t va); 194 #endif 195 static vm_page_t pmap_page_lookup (vm_object_t object, vm_pindex_t pindex); 196 static int pmap_unuse_pt (pmap_t, vm_offset_t, vm_page_t); 197 198 /* 199 * pmap_pte_quick: 200 * 201 * Super fast pmap_pte routine best used when scanning the pv lists. 202 * This eliminates many course-grained invltlb calls. Note that many of 203 * the pv list scans are across different pmaps and it is very wasteful 204 * to do an entire invltlb when checking a single mapping. 205 * 206 * Should only be called while in a critical section. 207 */ 208 #if JGPMAP32 209 static __inline pt_entry_t *pmap_pte(pmap_t pmap, vm_offset_t va); 210 211 static pt_entry_t * 212 pmap_pte_quick(pmap_t pmap, vm_offset_t va) 213 { 214 return pmap_pte(pmap, va); 215 } 216 #endif 217 218 /* Return a non-clipped PD index for a given VA */ 219 static __inline vm_pindex_t 220 pmap_pde_pindex(vm_offset_t va) 221 { 222 return va >> PDRSHIFT; 223 } 224 225 /* Return various clipped indexes for a given VA */ 226 static __inline vm_pindex_t 227 pmap_pte_index(vm_offset_t va) 228 { 229 230 return ((va >> PAGE_SHIFT) & ((1ul << NPTEPGSHIFT) - 1)); 231 } 232 233 static __inline vm_pindex_t 234 pmap_pde_index(vm_offset_t va) 235 { 236 237 return ((va >> PDRSHIFT) & ((1ul << NPDEPGSHIFT) - 1)); 238 } 239 240 static __inline vm_pindex_t 241 pmap_pdpe_index(vm_offset_t va) 242 { 243 244 return ((va >> PDPSHIFT) & ((1ul << NPDPEPGSHIFT) - 1)); 245 } 246 247 static __inline vm_pindex_t 248 pmap_pml4e_index(vm_offset_t va) 249 { 250 251 return ((va >> PML4SHIFT) & ((1ul << NPML4EPGSHIFT) - 1)); 252 } 253 254 /* Return a pointer to the PML4 slot that corresponds to a VA */ 255 static __inline pml4_entry_t * 256 pmap_pml4e(pmap_t pmap, vm_offset_t va) 257 { 258 259 return (&pmap->pm_pml4[pmap_pml4e_index(va)]); 260 } 261 262 /* Return a pointer to the PDP slot that corresponds to a VA */ 263 static __inline pdp_entry_t * 264 pmap_pml4e_to_pdpe(pml4_entry_t *pml4e, vm_offset_t va) 265 { 266 pdp_entry_t *pdpe; 267 268 pdpe = (pdp_entry_t *)PHYS_TO_DMAP(*pml4e & VPTE_FRAME); 269 return (&pdpe[pmap_pdpe_index(va)]); 270 } 271 272 /* Return a pointer to the PDP slot that corresponds to a VA */ 273 static __inline pdp_entry_t * 274 pmap_pdpe(pmap_t pmap, vm_offset_t va) 275 { 276 pml4_entry_t *pml4e; 277 278 pml4e = pmap_pml4e(pmap, va); 279 if ((*pml4e & VPTE_V) == 0) 280 return NULL; 281 return (pmap_pml4e_to_pdpe(pml4e, va)); 282 } 283 284 /* Return a pointer to the PD slot that corresponds to a VA */ 285 static __inline pd_entry_t * 286 pmap_pdpe_to_pde(pdp_entry_t *pdpe, vm_offset_t va) 287 { 288 pd_entry_t *pde; 289 290 pde = (pd_entry_t *)PHYS_TO_DMAP(*pdpe & VPTE_FRAME); 291 return (&pde[pmap_pde_index(va)]); 292 } 293 294 /* Return a pointer to the PD slot that corresponds to a VA */ 295 static __inline pd_entry_t * 296 pmap_pde(pmap_t pmap, vm_offset_t va) 297 { 298 pdp_entry_t *pdpe; 299 300 pdpe = pmap_pdpe(pmap, va); 301 if (pdpe == NULL || (*pdpe & VPTE_V) == 0) 302 return NULL; 303 return (pmap_pdpe_to_pde(pdpe, va)); 304 } 305 306 /* Return a pointer to the PT slot that corresponds to a VA */ 307 static __inline pt_entry_t * 308 pmap_pde_to_pte(pd_entry_t *pde, vm_offset_t va) 309 { 310 pt_entry_t *pte; 311 312 pte = (pt_entry_t *)PHYS_TO_DMAP(*pde & VPTE_FRAME); 313 return (&pte[pmap_pte_index(va)]); 314 } 315 316 /* Return a pointer to the PT slot that corresponds to a VA */ 317 static __inline pt_entry_t * 318 pmap_pte(pmap_t pmap, vm_offset_t va) 319 { 320 pd_entry_t *pde; 321 322 pde = pmap_pde(pmap, va); 323 if (pde == NULL || (*pde & VPTE_V) == 0) 324 return NULL; 325 if ((*pde & VPTE_PS) != 0) /* compat with i386 pmap_pte() */ 326 return ((pt_entry_t *)pde); 327 return (pmap_pde_to_pte(pde, va)); 328 } 329 330 331 #if JGV 332 PMAP_INLINE pt_entry_t * 333 vtopte(vm_offset_t va) 334 { 335 uint64_t mask = ((1ul << (NPTEPGSHIFT + NPDEPGSHIFT + 336 NPDPEPGSHIFT + NPML4EPGSHIFT)) - 1); 337 338 return (PTmap + ((va >> PAGE_SHIFT) & mask)); 339 } 340 341 static __inline pd_entry_t * 342 vtopde(vm_offset_t va) 343 { 344 uint64_t mask = ((1ul << (NPDEPGSHIFT + NPDPEPGSHIFT + 345 NPML4EPGSHIFT)) - 1); 346 347 return (PDmap + ((va >> PDRSHIFT) & mask)); 348 } 349 #else 350 static PMAP_INLINE pt_entry_t * 351 vtopte(vm_offset_t va) 352 { 353 pt_entry_t *x; 354 x = pmap_pte(&kernel_pmap, va); 355 assert(x != NULL); 356 return x; 357 } 358 359 static __inline pd_entry_t * 360 vtopde(vm_offset_t va) 361 { 362 pd_entry_t *x; 363 x = pmap_pde(&kernel_pmap, va); 364 assert(x != NULL); 365 return x; 366 } 367 #endif 368 369 static uint64_t 370 allocpages(vm_paddr_t *firstaddr, int n) 371 { 372 uint64_t ret; 373 374 ret = *firstaddr; 375 #if JGV 376 bzero((void *)ret, n * PAGE_SIZE); 377 #endif 378 *firstaddr += n * PAGE_SIZE; 379 return (ret); 380 } 381 382 static void 383 create_dmap_vmm(vm_paddr_t *firstaddr) 384 { 385 void *stack_addr; 386 int pml4_stack_index; 387 int pdp_stack_index; 388 int pd_stack_index; 389 long i,j; 390 int regs[4]; 391 int amd_feature; 392 393 uint64_t KPDP_DMAP_phys = allocpages(firstaddr, NDMPML4E); 394 uint64_t KPDP_VSTACK_phys = allocpages(firstaddr, 1); 395 uint64_t KPD_VSTACK_phys = allocpages(firstaddr, 1); 396 397 pml4_entry_t *KPML4virt = (pml4_entry_t *)PHYS_TO_DMAP(KPML4phys); 398 pdp_entry_t *KPDP_DMAP_virt = (pdp_entry_t *)PHYS_TO_DMAP(KPDP_DMAP_phys); 399 pdp_entry_t *KPDP_VSTACK_virt = (pdp_entry_t *)PHYS_TO_DMAP(KPDP_VSTACK_phys); 400 pd_entry_t *KPD_VSTACK_virt = (pd_entry_t *)PHYS_TO_DMAP(KPD_VSTACK_phys); 401 402 bzero(KPDP_DMAP_virt, NDMPML4E * PAGE_SIZE); 403 bzero(KPDP_VSTACK_virt, 1 * PAGE_SIZE); 404 bzero(KPD_VSTACK_virt, 1 * PAGE_SIZE); 405 406 do_cpuid(0x80000001, regs); 407 amd_feature = regs[3]; 408 409 /* Build the mappings for the first 512GB */ 410 if (amd_feature & AMDID_PAGE1GB) { 411 /* In pages of 1 GB, if supported */ 412 for (i = 0; i < NPDPEPG; i++) { 413 KPDP_DMAP_virt[i] = ((uint64_t)i << PDPSHIFT); 414 KPDP_DMAP_virt[i] |= VPTE_RW | VPTE_V | VPTE_PS | VPTE_U; 415 } 416 } else { 417 /* In page of 2MB, otherwise */ 418 for (i = 0; i < NPDPEPG; i++) { 419 uint64_t KPD_DMAP_phys = allocpages(firstaddr, 1); 420 pd_entry_t *KPD_DMAP_virt = (pd_entry_t *)PHYS_TO_DMAP(KPD_DMAP_phys); 421 422 bzero(KPD_DMAP_virt, PAGE_SIZE); 423 424 KPDP_DMAP_virt[i] = KPD_DMAP_phys; 425 KPDP_DMAP_virt[i] |= VPTE_RW | VPTE_V | VPTE_U; 426 427 /* For each PD, we have to allocate NPTEPG PT */ 428 for (j = 0; j < NPTEPG; j++) { 429 KPD_DMAP_virt[j] = (i << PDPSHIFT) | (j << PDRSHIFT); 430 KPD_DMAP_virt[j] |= VPTE_RW | VPTE_V | VPTE_PS | VPTE_U; 431 } 432 } 433 } 434 435 /* DMAP for the first 512G */ 436 KPML4virt[0] = KPDP_DMAP_phys; 437 KPML4virt[0] |= VPTE_RW | VPTE_V | VPTE_U; 438 439 /* create a 2 MB map of the new stack */ 440 pml4_stack_index = (uint64_t)&stack_addr >> PML4SHIFT; 441 KPML4virt[pml4_stack_index] = KPDP_VSTACK_phys; 442 KPML4virt[pml4_stack_index] |= VPTE_RW | VPTE_V | VPTE_U; 443 444 pdp_stack_index = ((uint64_t)&stack_addr & PML4MASK) >> PDPSHIFT; 445 KPDP_VSTACK_virt[pdp_stack_index] = KPD_VSTACK_phys; 446 KPDP_VSTACK_virt[pdp_stack_index] |= VPTE_RW | VPTE_V | VPTE_U; 447 448 pd_stack_index = ((uint64_t)&stack_addr & PDPMASK) >> PDRSHIFT; 449 KPD_VSTACK_virt[pd_stack_index] = (uint64_t) vkernel_stack; 450 KPD_VSTACK_virt[pd_stack_index] |= VPTE_RW | VPTE_V | VPTE_U | VPTE_PS; 451 } 452 453 static void 454 create_pagetables(vm_paddr_t *firstaddr, int64_t ptov_offset) 455 { 456 int i; 457 pml4_entry_t *KPML4virt; 458 pdp_entry_t *KPDPvirt; 459 pd_entry_t *KPDvirt; 460 pt_entry_t *KPTvirt; 461 int kpml4i = pmap_pml4e_index(ptov_offset); 462 int kpdpi = pmap_pdpe_index(ptov_offset); 463 int kpdi = pmap_pde_index(ptov_offset); 464 465 /* 466 * Calculate NKPT - number of kernel page tables. We have to 467 * accomodoate prealloction of the vm_page_array, dump bitmap, 468 * MSGBUF_SIZE, and other stuff. Be generous. 469 * 470 * Maxmem is in pages. 471 */ 472 nkpt = (Maxmem * (sizeof(struct vm_page) * 2) + MSGBUF_SIZE) / NBPDR; 473 /* 474 * Allocate pages 475 */ 476 KPML4phys = allocpages(firstaddr, 1); 477 KPDPphys = allocpages(firstaddr, NKPML4E); 478 KPDphys = allocpages(firstaddr, NKPDPE); 479 KPTphys = allocpages(firstaddr, nkpt); 480 481 KPML4virt = (pml4_entry_t *)PHYS_TO_DMAP(KPML4phys); 482 KPDPvirt = (pdp_entry_t *)PHYS_TO_DMAP(KPDPphys); 483 KPDvirt = (pd_entry_t *)PHYS_TO_DMAP(KPDphys); 484 KPTvirt = (pt_entry_t *)PHYS_TO_DMAP(KPTphys); 485 486 bzero(KPML4virt, 1 * PAGE_SIZE); 487 bzero(KPDPvirt, NKPML4E * PAGE_SIZE); 488 bzero(KPDvirt, NKPDPE * PAGE_SIZE); 489 bzero(KPTvirt, nkpt * PAGE_SIZE); 490 491 /* Now map the page tables at their location within PTmap */ 492 for (i = 0; i < nkpt; i++) { 493 KPDvirt[i + kpdi] = KPTphys + (i << PAGE_SHIFT); 494 KPDvirt[i + kpdi] |= VPTE_RW | VPTE_V | VPTE_U; 495 } 496 497 /* And connect up the PD to the PDP */ 498 for (i = 0; i < NKPDPE; i++) { 499 KPDPvirt[i + kpdpi] = KPDphys + (i << PAGE_SHIFT); 500 KPDPvirt[i + kpdpi] |= VPTE_RW | VPTE_V | VPTE_U; 501 } 502 503 /* And recursively map PML4 to itself in order to get PTmap */ 504 KPML4virt[PML4PML4I] = KPML4phys; 505 KPML4virt[PML4PML4I] |= VPTE_RW | VPTE_V | VPTE_U; 506 507 /* Connect the KVA slot up to the PML4 */ 508 KPML4virt[kpml4i] = KPDPphys; 509 KPML4virt[kpml4i] |= VPTE_RW | VPTE_V | VPTE_U; 510 } 511 512 /* 513 * Typically used to initialize a fictitious page by vm/device_pager.c 514 */ 515 void 516 pmap_page_init(struct vm_page *m) 517 { 518 vm_page_init(m); 519 TAILQ_INIT(&m->md.pv_list); 520 } 521 522 /* 523 * Bootstrap the system enough to run with virtual memory. 524 * 525 * On the i386 this is called after mapping has already been enabled 526 * and just syncs the pmap module with what has already been done. 527 * [We can't call it easily with mapping off since the kernel is not 528 * mapped with PA == VA, hence we would have to relocate every address 529 * from the linked base (virtual) address "KERNBASE" to the actual 530 * (physical) address starting relative to 0] 531 */ 532 void 533 pmap_bootstrap(vm_paddr_t *firstaddr, int64_t ptov_offset) 534 { 535 vm_offset_t va; 536 pt_entry_t *pte; 537 538 /* 539 * Create an initial set of page tables to run the kernel in. 540 */ 541 create_pagetables(firstaddr, ptov_offset); 542 543 /* Create the DMAP for the VMM */ 544 if(vmm_enabled) { 545 create_dmap_vmm(firstaddr); 546 } 547 548 virtual_start = KvaStart; 549 virtual_end = KvaEnd; 550 551 /* 552 * Initialize protection array. 553 */ 554 i386_protection_init(); 555 556 /* 557 * The kernel's pmap is statically allocated so we don't have to use 558 * pmap_create, which is unlikely to work correctly at this part of 559 * the boot sequence (XXX and which no longer exists). 560 * 561 * The kernel_pmap's pm_pteobj is used only for locking and not 562 * for mmu pages. 563 */ 564 kernel_pmap.pm_pml4 = (pml4_entry_t *)PHYS_TO_DMAP(KPML4phys); 565 kernel_pmap.pm_count = 1; 566 /* don't allow deactivation */ 567 CPUMASK_ASSALLONES(kernel_pmap.pm_active); 568 kernel_pmap.pm_pteobj = NULL; /* see pmap_init */ 569 TAILQ_INIT(&kernel_pmap.pm_pvlist); 570 TAILQ_INIT(&kernel_pmap.pm_pvlist_free); 571 lwkt_token_init(&kernel_pmap.pm_token, "kpmap_tok"); 572 spin_init(&kernel_pmap.pm_spin, "pmapbootstrap"); 573 574 /* 575 * Reserve some special page table entries/VA space for temporary 576 * mapping of pages. 577 */ 578 #define SYSMAP(c, p, v, n) \ 579 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n); 580 581 va = virtual_start; 582 pte = pmap_pte(&kernel_pmap, va); 583 /* 584 * CMAP1/CMAP2 are used for zeroing and copying pages. 585 */ 586 SYSMAP(caddr_t, CMAP1, CADDR1, 1) 587 588 #if JGV 589 /* 590 * Crashdump maps. 591 */ 592 SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS); 593 #endif 594 595 /* 596 * ptvmmap is used for reading arbitrary physical pages via 597 * /dev/mem. 598 */ 599 SYSMAP(caddr_t, ptmmap, ptvmmap, 1) 600 601 /* 602 * msgbufp is used to map the system message buffer. 603 * XXX msgbufmap is not used. 604 */ 605 SYSMAP(struct msgbuf *, msgbufmap, msgbufp, 606 atop(round_page(MSGBUF_SIZE))) 607 608 virtual_start = va; 609 610 *CMAP1 = 0; 611 /* Not ready to do an invltlb yet for VMM*/ 612 if (!vmm_enabled) 613 cpu_invltlb(); 614 615 } 616 617 /* 618 * Initialize the pmap module. 619 * Called by vm_init, to initialize any structures that the pmap 620 * system needs to map virtual memory. 621 * pmap_init has been enhanced to support in a fairly consistant 622 * way, discontiguous physical memory. 623 */ 624 void 625 pmap_init(void) 626 { 627 int i; 628 int initial_pvs; 629 630 /* 631 * object for kernel page table pages 632 */ 633 /* JG I think the number can be arbitrary */ 634 kptobj = vm_object_allocate(OBJT_DEFAULT, 5); 635 kernel_pmap.pm_pteobj = kptobj; 636 637 /* 638 * Allocate memory for random pmap data structures. Includes the 639 * pv_head_table. 640 */ 641 for(i = 0; i < vm_page_array_size; i++) { 642 vm_page_t m; 643 644 m = &vm_page_array[i]; 645 TAILQ_INIT(&m->md.pv_list); 646 m->md.pv_list_count = 0; 647 } 648 649 /* 650 * init the pv free list 651 */ 652 initial_pvs = vm_page_array_size; 653 if (initial_pvs < MINPV) 654 initial_pvs = MINPV; 655 pvzone = &pvzone_store; 656 pvinit = (struct pv_entry *) kmem_alloc(&kernel_map, 657 initial_pvs * sizeof (struct pv_entry)); 658 zbootinit(pvzone, "PV ENTRY", sizeof (struct pv_entry), pvinit, 659 initial_pvs); 660 661 /* 662 * Now it is safe to enable pv_table recording. 663 */ 664 pmap_initialized = TRUE; 665 } 666 667 /* 668 * Initialize the address space (zone) for the pv_entries. Set a 669 * high water mark so that the system can recover from excessive 670 * numbers of pv entries. 671 */ 672 void 673 pmap_init2(void) 674 { 675 int shpgperproc = PMAP_SHPGPERPROC; 676 677 TUNABLE_INT_FETCH("vm.pmap.shpgperproc", &shpgperproc); 678 pv_entry_max = shpgperproc * maxproc + vm_page_array_size; 679 TUNABLE_INT_FETCH("vm.pmap.pv_entries", &pv_entry_max); 680 pv_entry_high_water = 9 * (pv_entry_max / 10); 681 zinitna(pvzone, &pvzone_obj, NULL, 0, pv_entry_max, ZONE_INTERRUPT, 1); 682 } 683 684 685 /*************************************************** 686 * Low level helper routines..... 687 ***************************************************/ 688 689 /* 690 * The modification bit is not tracked for any pages in this range. XXX 691 * such pages in this maps should always use pmap_k*() functions and not 692 * be managed anyhow. 693 * 694 * XXX User and kernel address spaces are independant for virtual kernels, 695 * this function only applies to the kernel pmap. 696 */ 697 static int 698 pmap_track_modified(pmap_t pmap, vm_offset_t va) 699 { 700 if (pmap != &kernel_pmap) 701 return 1; 702 if ((va < clean_sva) || (va >= clean_eva)) 703 return 1; 704 else 705 return 0; 706 } 707 708 /* 709 * Extract the physical page address associated with the map/VA pair. 710 * 711 * No requirements. 712 */ 713 vm_paddr_t 714 pmap_extract(pmap_t pmap, vm_offset_t va) 715 { 716 vm_paddr_t rtval; 717 pt_entry_t *pte; 718 pd_entry_t pde, *pdep; 719 720 lwkt_gettoken(&vm_token); 721 rtval = 0; 722 pdep = pmap_pde(pmap, va); 723 if (pdep != NULL) { 724 pde = *pdep; 725 if (pde) { 726 if ((pde & VPTE_PS) != 0) { 727 /* JGV */ 728 rtval = (pde & PG_PS_FRAME) | (va & PDRMASK); 729 } else { 730 pte = pmap_pde_to_pte(pdep, va); 731 rtval = (*pte & VPTE_FRAME) | (va & PAGE_MASK); 732 } 733 } 734 } 735 lwkt_reltoken(&vm_token); 736 return rtval; 737 } 738 739 /* 740 * Similar to extract but checks protections, SMP-friendly short-cut for 741 * vm_fault_page[_quick](). 742 */ 743 vm_page_t 744 pmap_fault_page_quick(pmap_t pmap __unused, vm_offset_t vaddr __unused, 745 vm_prot_t prot __unused) 746 { 747 return(NULL); 748 } 749 750 /* 751 * Routine: pmap_kextract 752 * Function: 753 * Extract the physical page address associated 754 * kernel virtual address. 755 */ 756 vm_paddr_t 757 pmap_kextract(vm_offset_t va) 758 { 759 pd_entry_t pde; 760 vm_paddr_t pa; 761 762 KKASSERT(va >= KvaStart && va < KvaEnd); 763 764 /* 765 * The DMAP region is not included in [KvaStart, KvaEnd) 766 */ 767 #if 0 768 if (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS) { 769 pa = DMAP_TO_PHYS(va); 770 } else { 771 #endif 772 pde = *vtopde(va); 773 if (pde & VPTE_PS) { 774 /* JGV */ 775 pa = (pde & PG_PS_FRAME) | (va & PDRMASK); 776 } else { 777 /* 778 * Beware of a concurrent promotion that changes the 779 * PDE at this point! For example, vtopte() must not 780 * be used to access the PTE because it would use the 781 * new PDE. It is, however, safe to use the old PDE 782 * because the page table page is preserved by the 783 * promotion. 784 */ 785 pa = *pmap_pde_to_pte(&pde, va); 786 pa = (pa & VPTE_FRAME) | (va & PAGE_MASK); 787 } 788 #if 0 789 } 790 #endif 791 return pa; 792 } 793 794 /*************************************************** 795 * Low level mapping routines..... 796 ***************************************************/ 797 798 /* 799 * Enter a mapping into kernel_pmap. Mappings created in this fashion 800 * are not managed. Mappings must be immediately accessible on all cpus. 801 * 802 * Call pmap_inval_pte() to invalidate the virtual pte and clean out the 803 * real pmap and handle related races before storing the new vpte. 804 */ 805 void 806 pmap_kenter(vm_offset_t va, vm_paddr_t pa) 807 { 808 pt_entry_t *pte; 809 pt_entry_t npte; 810 811 KKASSERT(va >= KvaStart && va < KvaEnd); 812 npte = pa | VPTE_RW | VPTE_V | VPTE_U; 813 pte = vtopte(va); 814 if (*pte & VPTE_V) 815 pmap_inval_pte(pte, &kernel_pmap, va); 816 *pte = npte; 817 } 818 819 /* 820 * Enter an unmanaged KVA mapping for the private use of the current 821 * cpu only. pmap_kenter_sync() may be called to make the mapping usable 822 * by other cpus. 823 * 824 * It is illegal for the mapping to be accessed by other cpus unleess 825 * pmap_kenter_sync*() is called. 826 */ 827 void 828 pmap_kenter_quick(vm_offset_t va, vm_paddr_t pa) 829 { 830 pt_entry_t *pte; 831 pt_entry_t npte; 832 833 KKASSERT(va >= KvaStart && va < KvaEnd); 834 835 npte = (vpte_t)pa | VPTE_RW | VPTE_V | VPTE_U; 836 pte = vtopte(va); 837 838 if (*pte & VPTE_V) 839 pmap_inval_pte_quick(pte, &kernel_pmap, va); 840 *pte = npte; 841 } 842 843 /* 844 * Synchronize a kvm mapping originally made for the private use on 845 * some other cpu so it can be used on our cpu. Turns out to be the 846 * same madvise() call, because we have to sync the real pmaps anyway. 847 * 848 * XXX add MADV_RESYNC to improve performance. 849 */ 850 void 851 pmap_kenter_sync_quick(vm_offset_t va) 852 { 853 cpu_invlpg((void *)va); 854 } 855 856 /* 857 * Remove an unmanaged mapping created with pmap_kenter*(). 858 */ 859 void 860 pmap_kremove(vm_offset_t va) 861 { 862 pt_entry_t *pte; 863 864 KKASSERT(va >= KvaStart && va < KvaEnd); 865 866 pte = vtopte(va); 867 if (*pte & VPTE_V) 868 pmap_inval_pte(pte, &kernel_pmap, va); 869 *pte = 0; 870 } 871 872 /* 873 * Remove an unmanaged mapping created with pmap_kenter*() but synchronize 874 * only with this cpu. 875 * 876 * Unfortunately because we optimize new entries by testing VPTE_V later 877 * on, we actually still have to synchronize with all the cpus. XXX maybe 878 * store a junk value and test against 0 in the other places instead? 879 */ 880 void 881 pmap_kremove_quick(vm_offset_t va) 882 { 883 pt_entry_t *pte; 884 885 KKASSERT(va >= KvaStart && va < KvaEnd); 886 887 pte = vtopte(va); 888 if (*pte & VPTE_V) 889 pmap_inval_pte(pte, &kernel_pmap, va); /* NOT _quick */ 890 *pte = 0; 891 } 892 893 /* 894 * Used to map a range of physical addresses into kernel 895 * virtual address space. 896 * 897 * For now, VM is already on, we only need to map the 898 * specified memory. 899 */ 900 vm_offset_t 901 pmap_map(vm_offset_t *virtp, vm_paddr_t start, vm_paddr_t end, int prot) 902 { 903 return PHYS_TO_DMAP(start); 904 } 905 906 907 /* 908 * Map a set of unmanaged VM pages into KVM. 909 */ 910 void 911 pmap_qenter(vm_offset_t va, vm_page_t *m, int count) 912 { 913 vm_offset_t end_va; 914 915 end_va = va + count * PAGE_SIZE; 916 KKASSERT(va >= KvaStart && end_va < KvaEnd); 917 918 while (va < end_va) { 919 pt_entry_t *pte; 920 921 pte = vtopte(va); 922 if (*pte & VPTE_V) 923 pmap_inval_pte(pte, &kernel_pmap, va); 924 *pte = VM_PAGE_TO_PHYS(*m) | VPTE_RW | VPTE_V | VPTE_U; 925 va += PAGE_SIZE; 926 m++; 927 } 928 } 929 930 /* 931 * Undo the effects of pmap_qenter*(). 932 */ 933 void 934 pmap_qremove(vm_offset_t va, int count) 935 { 936 vm_offset_t end_va; 937 938 end_va = va + count * PAGE_SIZE; 939 KKASSERT(va >= KvaStart && end_va < KvaEnd); 940 941 while (va < end_va) { 942 pt_entry_t *pte; 943 944 pte = vtopte(va); 945 if (*pte & VPTE_V) 946 pmap_inval_pte(pte, &kernel_pmap, va); 947 *pte = 0; 948 va += PAGE_SIZE; 949 } 950 } 951 952 /* 953 * This routine works like vm_page_lookup() but also blocks as long as the 954 * page is busy. This routine does not busy the page it returns. 955 * 956 * Unless the caller is managing objects whos pages are in a known state, 957 * the call should be made with a critical section held so the page's object 958 * association remains valid on return. 959 */ 960 static vm_page_t 961 pmap_page_lookup(vm_object_t object, vm_pindex_t pindex) 962 { 963 vm_page_t m; 964 965 ASSERT_LWKT_TOKEN_HELD(vm_object_token(object)); 966 m = vm_page_lookup_busy_wait(object, pindex, FALSE, "pplookp"); 967 968 return(m); 969 } 970 971 /* 972 * Create a new thread and optionally associate it with a (new) process. 973 * NOTE! the new thread's cpu may not equal the current cpu. 974 */ 975 void 976 pmap_init_thread(thread_t td) 977 { 978 /* enforce pcb placement */ 979 td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_size) - 1; 980 td->td_savefpu = &td->td_pcb->pcb_save; 981 td->td_sp = (char *)td->td_pcb - 16; /* JG is -16 needed on x86_64? */ 982 } 983 984 /* 985 * This routine directly affects the fork perf for a process. 986 */ 987 void 988 pmap_init_proc(struct proc *p) 989 { 990 } 991 992 /*************************************************** 993 * Page table page management routines..... 994 ***************************************************/ 995 996 static __inline int pmap_unwire_pte_hold(pmap_t pmap, vm_offset_t va, 997 vm_page_t m); 998 999 /* 1000 * This routine unholds page table pages, and if the hold count 1001 * drops to zero, then it decrements the wire count. 1002 * 1003 * We must recheck that this is the last hold reference after busy-sleeping 1004 * on the page. 1005 */ 1006 static int 1007 _pmap_unwire_pte_hold(pmap_t pmap, vm_offset_t va, vm_page_t m) 1008 { 1009 vm_page_busy_wait(m, FALSE, "pmuwpt"); 1010 KASSERT(m->queue == PQ_NONE, 1011 ("_pmap_unwire_pte_hold: %p->queue != PQ_NONE", m)); 1012 1013 if (m->hold_count == 1) { 1014 /* 1015 * Unmap the page table page. 1016 */ 1017 //abort(); /* JG */ 1018 /* pmap_inval_add(info, pmap, -1); */ 1019 1020 if (m->pindex >= (NUPDE + NUPDPE)) { 1021 /* PDP page */ 1022 pml4_entry_t *pml4; 1023 pml4 = pmap_pml4e(pmap, va); 1024 *pml4 = 0; 1025 } else if (m->pindex >= NUPDE) { 1026 /* PD page */ 1027 pdp_entry_t *pdp; 1028 pdp = pmap_pdpe(pmap, va); 1029 *pdp = 0; 1030 } else { 1031 /* PT page */ 1032 pd_entry_t *pd; 1033 pd = pmap_pde(pmap, va); 1034 *pd = 0; 1035 } 1036 1037 KKASSERT(pmap->pm_stats.resident_count > 0); 1038 --pmap->pm_stats.resident_count; 1039 1040 if (pmap->pm_ptphint == m) 1041 pmap->pm_ptphint = NULL; 1042 1043 if (m->pindex < NUPDE) { 1044 /* We just released a PT, unhold the matching PD */ 1045 vm_page_t pdpg; 1046 1047 pdpg = PHYS_TO_VM_PAGE(*pmap_pdpe(pmap, va) & VPTE_FRAME); 1048 pmap_unwire_pte_hold(pmap, va, pdpg); 1049 } 1050 if (m->pindex >= NUPDE && m->pindex < (NUPDE + NUPDPE)) { 1051 /* We just released a PD, unhold the matching PDP */ 1052 vm_page_t pdppg; 1053 1054 pdppg = PHYS_TO_VM_PAGE(*pmap_pml4e(pmap, va) & VPTE_FRAME); 1055 pmap_unwire_pte_hold(pmap, va, pdppg); 1056 } 1057 1058 /* 1059 * This was our last hold, the page had better be unwired 1060 * after we decrement wire_count. 1061 * 1062 * FUTURE NOTE: shared page directory page could result in 1063 * multiple wire counts. 1064 */ 1065 vm_page_unhold(m); 1066 --m->wire_count; 1067 KKASSERT(m->wire_count == 0); 1068 atomic_add_int(&vmstats.v_wire_count, -1); 1069 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1070 vm_page_flash(m); 1071 vm_page_free_zero(m); 1072 return 1; 1073 } else { 1074 KKASSERT(m->hold_count > 1); 1075 vm_page_unhold(m); 1076 vm_page_wakeup(m); 1077 return 0; 1078 } 1079 } 1080 1081 static __inline int 1082 pmap_unwire_pte_hold(pmap_t pmap, vm_offset_t va, vm_page_t m) 1083 { 1084 KKASSERT(m->hold_count > 0); 1085 if (m->hold_count > 1) { 1086 vm_page_unhold(m); 1087 return 0; 1088 } else { 1089 return _pmap_unwire_pte_hold(pmap, va, m); 1090 } 1091 } 1092 1093 /* 1094 * After removing a page table entry, this routine is used to 1095 * conditionally free the page, and manage the hold/wire counts. 1096 */ 1097 static int 1098 pmap_unuse_pt(pmap_t pmap, vm_offset_t va, vm_page_t mpte) 1099 { 1100 /* JG Use FreeBSD/amd64 or FreeBSD/i386 ptepde approaches? */ 1101 vm_pindex_t ptepindex; 1102 1103 ASSERT_LWKT_TOKEN_HELD(vm_object_token(pmap->pm_pteobj)); 1104 1105 if (mpte == NULL) { 1106 /* 1107 * page table pages in the kernel_pmap are not managed. 1108 */ 1109 if (pmap == &kernel_pmap) 1110 return(0); 1111 ptepindex = pmap_pde_pindex(va); 1112 if (pmap->pm_ptphint && 1113 (pmap->pm_ptphint->pindex == ptepindex)) { 1114 mpte = pmap->pm_ptphint; 1115 } else { 1116 mpte = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1117 pmap->pm_ptphint = mpte; 1118 vm_page_wakeup(mpte); 1119 } 1120 } 1121 1122 return pmap_unwire_pte_hold(pmap, va, mpte); 1123 } 1124 1125 /* 1126 * Initialize pmap0/vmspace0 . Since process 0 never enters user mode we 1127 * just dummy it up so it works well enough for fork(). 1128 * 1129 * In DragonFly, process pmaps may only be used to manipulate user address 1130 * space, never kernel address space. 1131 */ 1132 void 1133 pmap_pinit0(struct pmap *pmap) 1134 { 1135 pmap_pinit(pmap); 1136 } 1137 1138 /* 1139 * Initialize a preallocated and zeroed pmap structure, 1140 * such as one in a vmspace structure. 1141 */ 1142 void 1143 pmap_pinit(struct pmap *pmap) 1144 { 1145 vm_page_t ptdpg; 1146 1147 /* 1148 * No need to allocate page table space yet but we do need a valid 1149 * page directory table. 1150 */ 1151 if (pmap->pm_pml4 == NULL) { 1152 pmap->pm_pml4 = 1153 (pml4_entry_t *)kmem_alloc_pageable(&kernel_map, PAGE_SIZE); 1154 } 1155 1156 /* 1157 * Allocate an object for the ptes 1158 */ 1159 if (pmap->pm_pteobj == NULL) 1160 pmap->pm_pteobj = vm_object_allocate(OBJT_DEFAULT, NUPDE + NUPDPE + PML4PML4I + 1); 1161 1162 /* 1163 * Allocate the page directory page, unless we already have 1164 * one cached. If we used the cached page the wire_count will 1165 * already be set appropriately. 1166 */ 1167 if ((ptdpg = pmap->pm_pdirm) == NULL) { 1168 ptdpg = vm_page_grab(pmap->pm_pteobj, 1169 NUPDE + NUPDPE + PML4PML4I, 1170 VM_ALLOC_NORMAL | VM_ALLOC_RETRY | 1171 VM_ALLOC_ZERO); 1172 pmap->pm_pdirm = ptdpg; 1173 vm_page_flag_clear(ptdpg, PG_MAPPED); 1174 vm_page_wire(ptdpg); 1175 vm_page_wakeup(ptdpg); 1176 pmap_kenter((vm_offset_t)pmap->pm_pml4, VM_PAGE_TO_PHYS(ptdpg)); 1177 } 1178 pmap->pm_count = 1; 1179 CPUMASK_ASSZERO(pmap->pm_active); 1180 pmap->pm_ptphint = NULL; 1181 TAILQ_INIT(&pmap->pm_pvlist); 1182 TAILQ_INIT(&pmap->pm_pvlist_free); 1183 spin_init(&pmap->pm_spin, "pmapinit"); 1184 lwkt_token_init(&pmap->pm_token, "pmap_tok"); 1185 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1186 pmap->pm_stats.resident_count = 1; 1187 } 1188 1189 /* 1190 * Clean up a pmap structure so it can be physically freed. This routine 1191 * is called by the vmspace dtor function. A great deal of pmap data is 1192 * left passively mapped to improve vmspace management so we have a bit 1193 * of cleanup work to do here. 1194 * 1195 * No requirements. 1196 */ 1197 void 1198 pmap_puninit(pmap_t pmap) 1199 { 1200 vm_page_t p; 1201 1202 KKASSERT(CPUMASK_TESTZERO(pmap->pm_active)); 1203 if ((p = pmap->pm_pdirm) != NULL) { 1204 KKASSERT(pmap->pm_pml4 != NULL); 1205 pmap_kremove((vm_offset_t)pmap->pm_pml4); 1206 vm_page_busy_wait(p, FALSE, "pgpun"); 1207 p->wire_count--; 1208 atomic_add_int(&vmstats.v_wire_count, -1); 1209 vm_page_free_zero(p); 1210 pmap->pm_pdirm = NULL; 1211 } 1212 if (pmap->pm_pml4) { 1213 kmem_free(&kernel_map, (vm_offset_t)pmap->pm_pml4, PAGE_SIZE); 1214 pmap->pm_pml4 = NULL; 1215 } 1216 if (pmap->pm_pteobj) { 1217 vm_object_deallocate(pmap->pm_pteobj); 1218 pmap->pm_pteobj = NULL; 1219 } 1220 } 1221 1222 /* 1223 * Wire in kernel global address entries. To avoid a race condition 1224 * between pmap initialization and pmap_growkernel, this procedure 1225 * adds the pmap to the master list (which growkernel scans to update), 1226 * then copies the template. 1227 * 1228 * In a virtual kernel there are no kernel global address entries. 1229 * 1230 * No requirements. 1231 */ 1232 void 1233 pmap_pinit2(struct pmap *pmap) 1234 { 1235 spin_lock(&pmap_spin); 1236 TAILQ_INSERT_TAIL(&pmap_list, pmap, pm_pmnode); 1237 spin_unlock(&pmap_spin); 1238 } 1239 1240 /* 1241 * Attempt to release and free a vm_page in a pmap. Returns 1 on success, 1242 * 0 on failure (if the procedure had to sleep). 1243 * 1244 * When asked to remove the page directory page itself, we actually just 1245 * leave it cached so we do not have to incur the SMP inval overhead of 1246 * removing the kernel mapping. pmap_puninit() will take care of it. 1247 */ 1248 static int 1249 pmap_release_free_page(struct pmap *pmap, vm_page_t p) 1250 { 1251 /* 1252 * This code optimizes the case of freeing non-busy 1253 * page-table pages. Those pages are zero now, and 1254 * might as well be placed directly into the zero queue. 1255 */ 1256 if (vm_page_busy_try(p, FALSE)) { 1257 vm_page_sleep_busy(p, FALSE, "pmaprl"); 1258 return 0; 1259 } 1260 1261 /* 1262 * Remove the page table page from the processes address space. 1263 */ 1264 if (p->pindex == NUPDE + NUPDPE + PML4PML4I) { 1265 /* 1266 * We are the pml4 table itself. 1267 */ 1268 /* XXX anything to do here? */ 1269 } else if (p->pindex >= (NUPDE + NUPDPE)) { 1270 /* 1271 * We are a PDP page. 1272 * We look for the PML4 entry that points to us. 1273 */ 1274 vm_page_t m4 = vm_page_lookup(pmap->pm_pteobj, NUPDE + NUPDPE + PML4PML4I); 1275 KKASSERT(m4 != NULL); 1276 pml4_entry_t *pml4 = (pml4_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m4)); 1277 int idx = (p->pindex - (NUPDE + NUPDPE)) % NPML4EPG; 1278 KKASSERT(pml4[idx] != 0); 1279 pml4[idx] = 0; 1280 m4->hold_count--; 1281 /* JG What about wire_count? */ 1282 } else if (p->pindex >= NUPDE) { 1283 /* 1284 * We are a PD page. 1285 * We look for the PDP entry that points to us. 1286 */ 1287 vm_page_t m3 = vm_page_lookup(pmap->pm_pteobj, NUPDE + NUPDPE + (p->pindex - NUPDE) / NPDPEPG); 1288 KKASSERT(m3 != NULL); 1289 pdp_entry_t *pdp = (pdp_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m3)); 1290 int idx = (p->pindex - NUPDE) % NPDPEPG; 1291 KKASSERT(pdp[idx] != 0); 1292 pdp[idx] = 0; 1293 m3->hold_count--; 1294 /* JG What about wire_count? */ 1295 } else { 1296 /* We are a PT page. 1297 * We look for the PD entry that points to us. 1298 */ 1299 vm_page_t m2 = vm_page_lookup(pmap->pm_pteobj, NUPDE + p->pindex / NPDEPG); 1300 KKASSERT(m2 != NULL); 1301 pd_entry_t *pd = (pd_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m2)); 1302 int idx = p->pindex % NPDEPG; 1303 pd[idx] = 0; 1304 m2->hold_count--; 1305 /* JG What about wire_count? */ 1306 } 1307 KKASSERT(pmap->pm_stats.resident_count > 0); 1308 --pmap->pm_stats.resident_count; 1309 1310 if (p->hold_count) { 1311 panic("pmap_release: freeing held pt page " 1312 "pmap=%p pg=%p dmap=%p pi=%ld {%ld,%ld,%ld}", 1313 pmap, p, (void *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(p)), 1314 p->pindex, NUPDE, NUPDPE, PML4PML4I); 1315 } 1316 if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex)) 1317 pmap->pm_ptphint = NULL; 1318 1319 /* 1320 * We leave the top-level page table page cached, wired, and mapped in 1321 * the pmap until the dtor function (pmap_puninit()) gets called. 1322 * However, still clean it up so we can set PG_ZERO. 1323 */ 1324 if (p->pindex == NUPDE + NUPDPE + PML4PML4I) { 1325 bzero(pmap->pm_pml4, PAGE_SIZE); 1326 vm_page_flag_set(p, PG_ZERO); 1327 vm_page_wakeup(p); 1328 } else { 1329 abort(); 1330 p->wire_count--; 1331 atomic_add_int(&vmstats.v_wire_count, -1); 1332 /* JG eventually revert to using vm_page_free_zero() */ 1333 vm_page_free(p); 1334 } 1335 return 1; 1336 } 1337 1338 /* 1339 * this routine is called if the page table page is not 1340 * mapped correctly. 1341 */ 1342 static vm_page_t 1343 _pmap_allocpte(pmap_t pmap, vm_pindex_t ptepindex) 1344 { 1345 vm_page_t m, pdppg, pdpg; 1346 1347 /* 1348 * Find or fabricate a new pagetable page. Handle allocation 1349 * races by checking m->valid. 1350 */ 1351 m = vm_page_grab(pmap->pm_pteobj, ptepindex, 1352 VM_ALLOC_NORMAL | VM_ALLOC_ZERO | VM_ALLOC_RETRY); 1353 1354 KASSERT(m->queue == PQ_NONE, 1355 ("_pmap_allocpte: %p->queue != PQ_NONE", m)); 1356 1357 /* 1358 * Increment the hold count for the page we will be returning to 1359 * the caller. 1360 */ 1361 m->hold_count++; 1362 vm_page_wire(m); 1363 1364 /* 1365 * Map the pagetable page into the process address space, if 1366 * it isn't already there. 1367 */ 1368 ++pmap->pm_stats.resident_count; 1369 1370 if (ptepindex >= (NUPDE + NUPDPE)) { 1371 pml4_entry_t *pml4; 1372 vm_pindex_t pml4index; 1373 1374 /* Wire up a new PDP page */ 1375 pml4index = ptepindex - (NUPDE + NUPDPE); 1376 pml4 = &pmap->pm_pml4[pml4index]; 1377 *pml4 = VM_PAGE_TO_PHYS(m) | 1378 VPTE_RW | VPTE_V | VPTE_U | 1379 VPTE_A | VPTE_M; 1380 } else if (ptepindex >= NUPDE) { 1381 vm_pindex_t pml4index; 1382 vm_pindex_t pdpindex; 1383 pml4_entry_t *pml4; 1384 pdp_entry_t *pdp; 1385 1386 /* Wire up a new PD page */ 1387 pdpindex = ptepindex - NUPDE; 1388 pml4index = pdpindex >> NPML4EPGSHIFT; 1389 1390 pml4 = &pmap->pm_pml4[pml4index]; 1391 if ((*pml4 & VPTE_V) == 0) { 1392 /* Have to allocate a new PDP page, recurse */ 1393 if (_pmap_allocpte(pmap, NUPDE + NUPDPE + pml4index) 1394 == NULL) { 1395 --m->wire_count; 1396 vm_page_free(m); 1397 return (NULL); 1398 } 1399 } else { 1400 /* Add reference to the PDP page */ 1401 pdppg = PHYS_TO_VM_PAGE(*pml4 & VPTE_FRAME); 1402 pdppg->hold_count++; 1403 } 1404 pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & VPTE_FRAME); 1405 1406 /* Now find the pdp page */ 1407 pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)]; 1408 KKASSERT(*pdp == 0); /* JG DEBUG64 */ 1409 *pdp = VM_PAGE_TO_PHYS(m) | VPTE_RW | VPTE_V | VPTE_U | 1410 VPTE_A | VPTE_M; 1411 } else { 1412 vm_pindex_t pml4index; 1413 vm_pindex_t pdpindex; 1414 pml4_entry_t *pml4; 1415 pdp_entry_t *pdp; 1416 pd_entry_t *pd; 1417 1418 /* Wire up a new PT page */ 1419 pdpindex = ptepindex >> NPDPEPGSHIFT; 1420 pml4index = pdpindex >> NPML4EPGSHIFT; 1421 1422 /* First, find the pdp and check that its valid. */ 1423 pml4 = &pmap->pm_pml4[pml4index]; 1424 if ((*pml4 & VPTE_V) == 0) { 1425 /* We miss a PDP page. We ultimately need a PD page. 1426 * Recursively allocating a PD page will allocate 1427 * the missing PDP page and will also allocate 1428 * the PD page we need. 1429 */ 1430 /* Have to allocate a new PD page, recurse */ 1431 if (_pmap_allocpte(pmap, NUPDE + pdpindex) 1432 == NULL) { 1433 --m->wire_count; 1434 vm_page_free(m); 1435 return (NULL); 1436 } 1437 pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & VPTE_FRAME); 1438 pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)]; 1439 } else { 1440 pdp = (pdp_entry_t *)PHYS_TO_DMAP(*pml4 & VPTE_FRAME); 1441 pdp = &pdp[pdpindex & ((1ul << NPDPEPGSHIFT) - 1)]; 1442 if ((*pdp & VPTE_V) == 0) { 1443 /* Have to allocate a new PD page, recurse */ 1444 if (_pmap_allocpte(pmap, NUPDE + pdpindex) 1445 == NULL) { 1446 --m->wire_count; 1447 vm_page_free(m); 1448 return (NULL); 1449 } 1450 } else { 1451 /* Add reference to the PD page */ 1452 pdpg = PHYS_TO_VM_PAGE(*pdp & VPTE_FRAME); 1453 pdpg->hold_count++; 1454 } 1455 } 1456 pd = (pd_entry_t *)PHYS_TO_DMAP(*pdp & VPTE_FRAME); 1457 1458 /* Now we know where the page directory page is */ 1459 pd = &pd[ptepindex & ((1ul << NPDEPGSHIFT) - 1)]; 1460 KKASSERT(*pd == 0); /* JG DEBUG64 */ 1461 *pd = VM_PAGE_TO_PHYS(m) | VPTE_RW | VPTE_V | VPTE_U | 1462 VPTE_A | VPTE_M; 1463 } 1464 1465 /* 1466 * Set the page table hint 1467 */ 1468 pmap->pm_ptphint = m; 1469 vm_page_flag_set(m, PG_MAPPED); 1470 vm_page_wakeup(m); 1471 1472 return m; 1473 } 1474 1475 /* 1476 * Determine the page table page required to access the VA in the pmap 1477 * and allocate it if necessary. Return a held vm_page_t for the page. 1478 * 1479 * Only used with user pmaps. 1480 */ 1481 static vm_page_t 1482 pmap_allocpte(pmap_t pmap, vm_offset_t va) 1483 { 1484 vm_pindex_t ptepindex; 1485 pd_entry_t *pd; 1486 vm_page_t m; 1487 1488 ASSERT_LWKT_TOKEN_HELD(vm_object_token(pmap->pm_pteobj)); 1489 1490 /* 1491 * Calculate pagetable page index 1492 */ 1493 ptepindex = pmap_pde_pindex(va); 1494 1495 /* 1496 * Get the page directory entry 1497 */ 1498 pd = pmap_pde(pmap, va); 1499 1500 /* 1501 * This supports switching from a 2MB page to a 1502 * normal 4K page. 1503 */ 1504 if (pd != NULL && (*pd & (VPTE_PS | VPTE_V)) == (VPTE_PS | VPTE_V)) { 1505 panic("no promotion/demotion yet"); 1506 *pd = 0; 1507 pd = NULL; 1508 /*cpu_invltlb();*/ 1509 /*smp_invltlb();*/ 1510 } 1511 1512 /* 1513 * If the page table page is mapped, we just increment the 1514 * hold count, and activate it. 1515 */ 1516 if (pd != NULL && (*pd & VPTE_V) != 0) { 1517 /* YYY hint is used here on i386 */ 1518 m = pmap_page_lookup(pmap->pm_pteobj, ptepindex); 1519 pmap->pm_ptphint = m; 1520 vm_page_hold(m); 1521 vm_page_wakeup(m); 1522 return m; 1523 } 1524 /* 1525 * Here if the pte page isn't mapped, or if it has been deallocated. 1526 */ 1527 return _pmap_allocpte(pmap, ptepindex); 1528 } 1529 1530 1531 /*************************************************** 1532 * Pmap allocation/deallocation routines. 1533 ***************************************************/ 1534 1535 /* 1536 * Release any resources held by the given physical map. 1537 * Called when a pmap initialized by pmap_pinit is being released. 1538 * Should only be called if the map contains no valid mappings. 1539 * 1540 * Caller must hold pmap->pm_token 1541 */ 1542 static int pmap_release_callback(struct vm_page *p, void *data); 1543 1544 void 1545 pmap_release(struct pmap *pmap) 1546 { 1547 vm_object_t object = pmap->pm_pteobj; 1548 struct rb_vm_page_scan_info info; 1549 1550 KKASSERT(pmap != &kernel_pmap); 1551 1552 #if defined(DIAGNOSTIC) 1553 if (object->ref_count != 1) 1554 panic("pmap_release: pteobj reference count != 1"); 1555 #endif 1556 1557 info.pmap = pmap; 1558 info.object = object; 1559 1560 spin_lock(&pmap_spin); 1561 TAILQ_REMOVE(&pmap_list, pmap, pm_pmnode); 1562 spin_unlock(&pmap_spin); 1563 1564 vm_object_hold(object); 1565 do { 1566 info.error = 0; 1567 info.mpte = NULL; 1568 info.limit = object->generation; 1569 1570 vm_page_rb_tree_RB_SCAN(&object->rb_memq, NULL, 1571 pmap_release_callback, &info); 1572 if (info.error == 0 && info.mpte) { 1573 if (!pmap_release_free_page(pmap, info.mpte)) 1574 info.error = 1; 1575 } 1576 } while (info.error); 1577 vm_object_drop(object); 1578 } 1579 1580 static int 1581 pmap_release_callback(struct vm_page *p, void *data) 1582 { 1583 struct rb_vm_page_scan_info *info = data; 1584 1585 if (p->pindex == NUPDE + NUPDPE + PML4PML4I) { 1586 info->mpte = p; 1587 return(0); 1588 } 1589 if (!pmap_release_free_page(info->pmap, p)) { 1590 info->error = 1; 1591 return(-1); 1592 } 1593 if (info->object->generation != info->limit) { 1594 info->error = 1; 1595 return(-1); 1596 } 1597 return(0); 1598 } 1599 1600 /* 1601 * Grow the number of kernel page table entries, if needed. 1602 * 1603 * No requirements. 1604 */ 1605 void 1606 pmap_growkernel(vm_offset_t kstart, vm_offset_t kend) 1607 { 1608 vm_offset_t addr; 1609 vm_paddr_t paddr; 1610 vm_offset_t ptppaddr; 1611 vm_page_t nkpg; 1612 pd_entry_t *pde, newpdir; 1613 pdp_entry_t newpdp; 1614 1615 addr = kend; 1616 1617 vm_object_hold(kptobj); 1618 if (kernel_vm_end == 0) { 1619 kernel_vm_end = KvaStart; 1620 nkpt = 0; 1621 while ((*pmap_pde(&kernel_pmap, kernel_vm_end) & VPTE_V) != 0) { 1622 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1); 1623 nkpt++; 1624 if (kernel_vm_end - 1 >= kernel_map.max_offset) { 1625 kernel_vm_end = kernel_map.max_offset; 1626 break; 1627 } 1628 } 1629 } 1630 addr = roundup2(addr, PAGE_SIZE * NPTEPG); 1631 if (addr - 1 >= kernel_map.max_offset) 1632 addr = kernel_map.max_offset; 1633 while (kernel_vm_end < addr) { 1634 pde = pmap_pde(&kernel_pmap, kernel_vm_end); 1635 if (pde == NULL) { 1636 /* We need a new PDP entry */ 1637 nkpg = vm_page_alloc(kptobj, nkpt, 1638 VM_ALLOC_NORMAL | VM_ALLOC_SYSTEM 1639 | VM_ALLOC_INTERRUPT); 1640 if (nkpg == NULL) { 1641 panic("pmap_growkernel: no memory to " 1642 "grow kernel"); 1643 } 1644 paddr = VM_PAGE_TO_PHYS(nkpg); 1645 if ((nkpg->flags & PG_ZERO) == 0) 1646 pmap_zero_page(paddr); 1647 vm_page_flag_clear(nkpg, PG_ZERO); 1648 newpdp = (pdp_entry_t)(paddr | 1649 VPTE_V | VPTE_RW | VPTE_U | 1650 VPTE_A | VPTE_M); 1651 *pmap_pdpe(&kernel_pmap, kernel_vm_end) = newpdp; 1652 nkpt++; 1653 continue; /* try again */ 1654 } 1655 if ((*pde & VPTE_V) != 0) { 1656 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & 1657 ~(PAGE_SIZE * NPTEPG - 1); 1658 if (kernel_vm_end - 1 >= kernel_map.max_offset) { 1659 kernel_vm_end = kernel_map.max_offset; 1660 break; 1661 } 1662 continue; 1663 } 1664 1665 /* 1666 * This index is bogus, but out of the way 1667 */ 1668 nkpg = vm_page_alloc(kptobj, nkpt, 1669 VM_ALLOC_NORMAL | 1670 VM_ALLOC_SYSTEM | 1671 VM_ALLOC_INTERRUPT); 1672 if (nkpg == NULL) 1673 panic("pmap_growkernel: no memory to grow kernel"); 1674 1675 vm_page_wire(nkpg); 1676 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 1677 pmap_zero_page(ptppaddr); 1678 vm_page_flag_clear(nkpg, PG_ZERO); 1679 newpdir = (pd_entry_t)(ptppaddr | 1680 VPTE_V | VPTE_RW | VPTE_U | 1681 VPTE_A | VPTE_M); 1682 *pmap_pde(&kernel_pmap, kernel_vm_end) = newpdir; 1683 nkpt++; 1684 1685 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & 1686 ~(PAGE_SIZE * NPTEPG - 1); 1687 if (kernel_vm_end - 1 >= kernel_map.max_offset) { 1688 kernel_vm_end = kernel_map.max_offset; 1689 break; 1690 } 1691 } 1692 vm_object_drop(kptobj); 1693 } 1694 1695 /* 1696 * Add a reference to the specified pmap. 1697 * 1698 * No requirements. 1699 */ 1700 void 1701 pmap_reference(pmap_t pmap) 1702 { 1703 if (pmap) { 1704 lwkt_gettoken(&vm_token); 1705 ++pmap->pm_count; 1706 lwkt_reltoken(&vm_token); 1707 } 1708 } 1709 1710 /************************************************************************ 1711 * VMSPACE MANAGEMENT * 1712 ************************************************************************ 1713 * 1714 * The VMSPACE management we do in our virtual kernel must be reflected 1715 * in the real kernel. This is accomplished by making vmspace system 1716 * calls to the real kernel. 1717 */ 1718 void 1719 cpu_vmspace_alloc(struct vmspace *vm) 1720 { 1721 int r; 1722 void *rp; 1723 vpte_t vpte; 1724 1725 /* 1726 * If VMM enable, don't do nothing, we 1727 * are able to use real page tables 1728 */ 1729 if (vmm_enabled) 1730 return; 1731 1732 #define USER_SIZE (VM_MAX_USER_ADDRESS - VM_MIN_USER_ADDRESS) 1733 1734 if (vmspace_create(&vm->vm_pmap, 0, NULL) < 0) 1735 panic("vmspace_create() failed"); 1736 1737 rp = vmspace_mmap(&vm->vm_pmap, VM_MIN_USER_ADDRESS, USER_SIZE, 1738 PROT_READ|PROT_WRITE, 1739 MAP_FILE|MAP_SHARED|MAP_VPAGETABLE|MAP_FIXED, 1740 MemImageFd, 0); 1741 if (rp == MAP_FAILED) 1742 panic("vmspace_mmap: failed"); 1743 vmspace_mcontrol(&vm->vm_pmap, VM_MIN_USER_ADDRESS, USER_SIZE, 1744 MADV_NOSYNC, 0); 1745 vpte = VM_PAGE_TO_PHYS(vmspace_pmap(vm)->pm_pdirm) | VPTE_RW | VPTE_V | VPTE_U; 1746 r = vmspace_mcontrol(&vm->vm_pmap, VM_MIN_USER_ADDRESS, USER_SIZE, 1747 MADV_SETMAP, vpte); 1748 if (r < 0) 1749 panic("vmspace_mcontrol: failed"); 1750 } 1751 1752 void 1753 cpu_vmspace_free(struct vmspace *vm) 1754 { 1755 /* 1756 * If VMM enable, don't do nothing, we 1757 * are able to use real page tables 1758 */ 1759 if (vmm_enabled) 1760 return; 1761 1762 if (vmspace_destroy(&vm->vm_pmap) < 0) 1763 panic("vmspace_destroy() failed"); 1764 } 1765 1766 /*************************************************** 1767 * page management routines. 1768 ***************************************************/ 1769 1770 /* 1771 * free the pv_entry back to the free list. This function may be 1772 * called from an interrupt. 1773 */ 1774 static __inline void 1775 free_pv_entry(pv_entry_t pv) 1776 { 1777 pv_entry_count--; 1778 KKASSERT(pv_entry_count >= 0); 1779 zfree(pvzone, pv); 1780 } 1781 1782 /* 1783 * get a new pv_entry, allocating a block from the system 1784 * when needed. This function may be called from an interrupt. 1785 */ 1786 static pv_entry_t 1787 get_pv_entry(void) 1788 { 1789 pv_entry_count++; 1790 if (pv_entry_high_water && 1791 (pv_entry_count > pv_entry_high_water) && 1792 (pmap_pagedaemon_waken == 0)) { 1793 pmap_pagedaemon_waken = 1; 1794 wakeup(&vm_pages_needed); 1795 } 1796 return zalloc(pvzone); 1797 } 1798 1799 /* 1800 * This routine is very drastic, but can save the system 1801 * in a pinch. 1802 * 1803 * No requirements. 1804 */ 1805 void 1806 pmap_collect(void) 1807 { 1808 int i; 1809 vm_page_t m; 1810 static int warningdone=0; 1811 1812 if (pmap_pagedaemon_waken == 0) 1813 return; 1814 lwkt_gettoken(&vm_token); 1815 pmap_pagedaemon_waken = 0; 1816 1817 if (warningdone < 5) { 1818 kprintf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n"); 1819 warningdone++; 1820 } 1821 1822 for (i = 0; i < vm_page_array_size; i++) { 1823 m = &vm_page_array[i]; 1824 if (m->wire_count || m->hold_count) 1825 continue; 1826 if (vm_page_busy_try(m, TRUE) == 0) { 1827 if (m->wire_count == 0 && m->hold_count == 0) { 1828 pmap_remove_all(m); 1829 } 1830 vm_page_wakeup(m); 1831 } 1832 } 1833 lwkt_reltoken(&vm_token); 1834 } 1835 1836 1837 /* 1838 * If it is the first entry on the list, it is actually 1839 * in the header and we must copy the following entry up 1840 * to the header. Otherwise we must search the list for 1841 * the entry. In either case we free the now unused entry. 1842 * 1843 * caller must hold vm_token. 1844 */ 1845 static int 1846 pmap_remove_entry(struct pmap *pmap, vm_page_t m, vm_offset_t va) 1847 { 1848 pv_entry_t pv; 1849 int rtval; 1850 1851 if (m->md.pv_list_count < pmap->pm_stats.resident_count) { 1852 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 1853 if (pmap == pv->pv_pmap && va == pv->pv_va) 1854 break; 1855 } 1856 } else { 1857 TAILQ_FOREACH(pv, &pmap->pm_pvlist, pv_plist) { 1858 if (va == pv->pv_va) 1859 break; 1860 } 1861 } 1862 1863 /* 1864 * Note that pv_ptem is NULL if the page table page itself is not 1865 * managed, even if the page being removed IS managed. 1866 */ 1867 rtval = 0; 1868 /* JGXXX When can 'pv' be NULL? */ 1869 if (pv) { 1870 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 1871 m->md.pv_list_count--; 1872 atomic_add_int(&m->object->agg_pv_list_count, -1); 1873 KKASSERT(m->md.pv_list_count >= 0); 1874 if (TAILQ_EMPTY(&m->md.pv_list)) 1875 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 1876 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 1877 ++pmap->pm_generation; 1878 KKASSERT(pmap->pm_pteobj != NULL); 1879 vm_object_hold(pmap->pm_pteobj); 1880 rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem); 1881 vm_object_drop(pmap->pm_pteobj); 1882 free_pv_entry(pv); 1883 } 1884 return rtval; 1885 } 1886 1887 /* 1888 * Create a pv entry for page at pa for (pmap, va). If the page table page 1889 * holding the VA is managed, mpte will be non-NULL. 1890 */ 1891 static void 1892 pmap_insert_entry(pmap_t pmap, vm_offset_t va, vm_page_t mpte, vm_page_t m) 1893 { 1894 pv_entry_t pv; 1895 1896 crit_enter(); 1897 pv = get_pv_entry(); 1898 pv->pv_va = va; 1899 pv->pv_pmap = pmap; 1900 pv->pv_ptem = mpte; 1901 1902 TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist); 1903 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 1904 m->md.pv_list_count++; 1905 atomic_add_int(&m->object->agg_pv_list_count, 1); 1906 1907 crit_exit(); 1908 } 1909 1910 /* 1911 * pmap_remove_pte: do the things to unmap a page in a process 1912 */ 1913 static int 1914 pmap_remove_pte(struct pmap *pmap, pt_entry_t *ptq, vm_offset_t va) 1915 { 1916 pt_entry_t oldpte; 1917 vm_page_t m; 1918 1919 oldpte = pmap_inval_loadandclear(ptq, pmap, va); 1920 if (oldpte & VPTE_WIRED) 1921 --pmap->pm_stats.wired_count; 1922 KKASSERT(pmap->pm_stats.wired_count >= 0); 1923 1924 #if 0 1925 /* 1926 * Machines that don't support invlpg, also don't support 1927 * PG_G. XXX PG_G is disabled for SMP so don't worry about 1928 * the SMP case. 1929 */ 1930 if (oldpte & PG_G) 1931 cpu_invlpg((void *)va); 1932 #endif 1933 KKASSERT(pmap->pm_stats.resident_count > 0); 1934 --pmap->pm_stats.resident_count; 1935 if (oldpte & VPTE_MANAGED) { 1936 m = PHYS_TO_VM_PAGE(oldpte); 1937 if (oldpte & VPTE_M) { 1938 #if defined(PMAP_DIAGNOSTIC) 1939 if (pmap_nw_modified(oldpte)) { 1940 kprintf("pmap_remove: modified page not " 1941 "writable: va: 0x%lx, pte: 0x%lx\n", 1942 va, oldpte); 1943 } 1944 #endif 1945 if (pmap_track_modified(pmap, va)) 1946 vm_page_dirty(m); 1947 } 1948 if (oldpte & VPTE_A) 1949 vm_page_flag_set(m, PG_REFERENCED); 1950 return pmap_remove_entry(pmap, m, va); 1951 } else { 1952 return pmap_unuse_pt(pmap, va, NULL); 1953 } 1954 1955 return 0; 1956 } 1957 1958 /* 1959 * pmap_remove_page: 1960 * 1961 * Remove a single page from a process address space. 1962 * 1963 * This function may not be called from an interrupt if the pmap is 1964 * not kernel_pmap. 1965 */ 1966 static void 1967 pmap_remove_page(struct pmap *pmap, vm_offset_t va) 1968 { 1969 pt_entry_t *pte; 1970 1971 pte = pmap_pte(pmap, va); 1972 if (pte == NULL) 1973 return; 1974 if ((*pte & VPTE_V) == 0) 1975 return; 1976 pmap_remove_pte(pmap, pte, va); 1977 } 1978 1979 /* 1980 * Remove the given range of addresses from the specified map. 1981 * 1982 * It is assumed that the start and end are properly rounded to 1983 * the page size. 1984 * 1985 * This function may not be called from an interrupt if the pmap is 1986 * not kernel_pmap. 1987 * 1988 * No requirements. 1989 */ 1990 void 1991 pmap_remove(struct pmap *pmap, vm_offset_t sva, vm_offset_t eva) 1992 { 1993 vm_offset_t va_next; 1994 pml4_entry_t *pml4e; 1995 pdp_entry_t *pdpe; 1996 pd_entry_t ptpaddr, *pde; 1997 pt_entry_t *pte; 1998 1999 if (pmap == NULL) 2000 return; 2001 2002 vm_object_hold(pmap->pm_pteobj); 2003 lwkt_gettoken(&vm_token); 2004 KKASSERT(pmap->pm_stats.resident_count >= 0); 2005 if (pmap->pm_stats.resident_count == 0) { 2006 lwkt_reltoken(&vm_token); 2007 vm_object_drop(pmap->pm_pteobj); 2008 return; 2009 } 2010 2011 /* 2012 * special handling of removing one page. a very 2013 * common operation and easy to short circuit some 2014 * code. 2015 */ 2016 if (sva + PAGE_SIZE == eva) { 2017 pde = pmap_pde(pmap, sva); 2018 if (pde && (*pde & VPTE_PS) == 0) { 2019 pmap_remove_page(pmap, sva); 2020 lwkt_reltoken(&vm_token); 2021 vm_object_drop(pmap->pm_pteobj); 2022 return; 2023 } 2024 } 2025 2026 for (; sva < eva; sva = va_next) { 2027 pml4e = pmap_pml4e(pmap, sva); 2028 if ((*pml4e & VPTE_V) == 0) { 2029 va_next = (sva + NBPML4) & ~PML4MASK; 2030 if (va_next < sva) 2031 va_next = eva; 2032 continue; 2033 } 2034 2035 pdpe = pmap_pml4e_to_pdpe(pml4e, sva); 2036 if ((*pdpe & VPTE_V) == 0) { 2037 va_next = (sva + NBPDP) & ~PDPMASK; 2038 if (va_next < sva) 2039 va_next = eva; 2040 continue; 2041 } 2042 2043 /* 2044 * Calculate index for next page table. 2045 */ 2046 va_next = (sva + NBPDR) & ~PDRMASK; 2047 if (va_next < sva) 2048 va_next = eva; 2049 2050 pde = pmap_pdpe_to_pde(pdpe, sva); 2051 ptpaddr = *pde; 2052 2053 /* 2054 * Weed out invalid mappings. 2055 */ 2056 if (ptpaddr == 0) 2057 continue; 2058 2059 /* 2060 * Check for large page. 2061 */ 2062 if ((ptpaddr & VPTE_PS) != 0) { 2063 /* JG FreeBSD has more complex treatment here */ 2064 KKASSERT(*pde != 0); 2065 pmap_inval_pde(pde, pmap, sva); 2066 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 2067 continue; 2068 } 2069 2070 /* 2071 * Limit our scan to either the end of the va represented 2072 * by the current page table page, or to the end of the 2073 * range being removed. 2074 */ 2075 if (va_next > eva) 2076 va_next = eva; 2077 2078 /* 2079 * NOTE: pmap_remove_pte() can block. 2080 */ 2081 for (pte = pmap_pde_to_pte(pde, sva); sva != va_next; pte++, 2082 sva += PAGE_SIZE) { 2083 if (*pte == 0) 2084 continue; 2085 if (pmap_remove_pte(pmap, pte, sva)) 2086 break; 2087 } 2088 } 2089 lwkt_reltoken(&vm_token); 2090 vm_object_drop(pmap->pm_pteobj); 2091 } 2092 2093 /* 2094 * Removes this physical page from all physical maps in which it resides. 2095 * Reflects back modify bits to the pager. 2096 * 2097 * This routine may not be called from an interrupt. 2098 * 2099 * No requirements. 2100 */ 2101 static void 2102 pmap_remove_all(vm_page_t m) 2103 { 2104 pt_entry_t *pte, tpte; 2105 pv_entry_t pv; 2106 2107 #if defined(PMAP_DIAGNOSTIC) 2108 /* 2109 * XXX this makes pmap_page_protect(NONE) illegal for non-managed 2110 * pages! 2111 */ 2112 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 2113 panic("pmap_page_protect: illegal for unmanaged page, va: 0x%08llx", (long long)VM_PAGE_TO_PHYS(m)); 2114 } 2115 #endif 2116 2117 lwkt_gettoken(&vm_token); 2118 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 2119 KKASSERT(pv->pv_pmap->pm_stats.resident_count > 0); 2120 --pv->pv_pmap->pm_stats.resident_count; 2121 2122 pte = pmap_pte(pv->pv_pmap, pv->pv_va); 2123 KKASSERT(pte != NULL); 2124 2125 tpte = pmap_inval_loadandclear(pte, pv->pv_pmap, pv->pv_va); 2126 if (tpte & VPTE_WIRED) 2127 pv->pv_pmap->pm_stats.wired_count--; 2128 KKASSERT(pv->pv_pmap->pm_stats.wired_count >= 0); 2129 2130 if (tpte & VPTE_A) 2131 vm_page_flag_set(m, PG_REFERENCED); 2132 2133 /* 2134 * Update the vm_page_t clean and reference bits. 2135 */ 2136 if (tpte & VPTE_M) { 2137 #if defined(PMAP_DIAGNOSTIC) 2138 if (pmap_nw_modified(tpte)) { 2139 kprintf( 2140 "pmap_remove_all: modified page not writable: va: 0x%lx, pte: 0x%lx\n", 2141 pv->pv_va, tpte); 2142 } 2143 #endif 2144 if (pmap_track_modified(pv->pv_pmap, pv->pv_va)) 2145 vm_page_dirty(m); 2146 } 2147 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 2148 TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist); 2149 ++pv->pv_pmap->pm_generation; 2150 m->md.pv_list_count--; 2151 atomic_add_int(&m->object->agg_pv_list_count, -1); 2152 KKASSERT(m->md.pv_list_count >= 0); 2153 if (TAILQ_EMPTY(&m->md.pv_list)) 2154 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 2155 vm_object_hold(pv->pv_pmap->pm_pteobj); 2156 pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem); 2157 vm_object_drop(pv->pv_pmap->pm_pteobj); 2158 free_pv_entry(pv); 2159 } 2160 KKASSERT((m->flags & (PG_MAPPED|PG_WRITEABLE)) == 0); 2161 lwkt_reltoken(&vm_token); 2162 } 2163 2164 /* 2165 * Set the physical protection on the specified range of this map 2166 * as requested. 2167 * 2168 * This function may not be called from an interrupt if the map is 2169 * not the kernel_pmap. 2170 * 2171 * No requirements. 2172 */ 2173 void 2174 pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 2175 { 2176 vm_offset_t va_next; 2177 pml4_entry_t *pml4e; 2178 pdp_entry_t *pdpe; 2179 pd_entry_t ptpaddr, *pde; 2180 pt_entry_t *pte; 2181 2182 /* JG review for NX */ 2183 2184 if (pmap == NULL) 2185 return; 2186 2187 if ((prot & VM_PROT_READ) == VM_PROT_NONE) { 2188 pmap_remove(pmap, sva, eva); 2189 return; 2190 } 2191 2192 if (prot & VM_PROT_WRITE) 2193 return; 2194 2195 lwkt_gettoken(&vm_token); 2196 2197 for (; sva < eva; sva = va_next) { 2198 2199 pml4e = pmap_pml4e(pmap, sva); 2200 if ((*pml4e & VPTE_V) == 0) { 2201 va_next = (sva + NBPML4) & ~PML4MASK; 2202 if (va_next < sva) 2203 va_next = eva; 2204 continue; 2205 } 2206 2207 pdpe = pmap_pml4e_to_pdpe(pml4e, sva); 2208 if ((*pdpe & VPTE_V) == 0) { 2209 va_next = (sva + NBPDP) & ~PDPMASK; 2210 if (va_next < sva) 2211 va_next = eva; 2212 continue; 2213 } 2214 2215 va_next = (sva + NBPDR) & ~PDRMASK; 2216 if (va_next < sva) 2217 va_next = eva; 2218 2219 pde = pmap_pdpe_to_pde(pdpe, sva); 2220 ptpaddr = *pde; 2221 2222 /* 2223 * Check for large page. 2224 */ 2225 if ((ptpaddr & VPTE_PS) != 0) { 2226 /* JG correct? */ 2227 pmap_clean_pde(pde, pmap, sva); 2228 pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE; 2229 continue; 2230 } 2231 2232 /* 2233 * Weed out invalid mappings. Note: we assume that the page 2234 * directory table is always allocated, and in kernel virtual. 2235 */ 2236 if (ptpaddr == 0) 2237 continue; 2238 2239 if (va_next > eva) 2240 va_next = eva; 2241 2242 for (pte = pmap_pde_to_pte(pde, sva); sva != va_next; pte++, 2243 sva += PAGE_SIZE) { 2244 pt_entry_t pbits; 2245 vm_page_t m; 2246 2247 /* 2248 * Clean managed pages and also check the accessed 2249 * bit. Just remove write perms for unmanaged 2250 * pages. Be careful of races, turning off write 2251 * access will force a fault rather then setting 2252 * the modified bit at an unexpected time. 2253 */ 2254 if (*pte & VPTE_MANAGED) { 2255 pbits = pmap_clean_pte(pte, pmap, sva); 2256 m = NULL; 2257 if (pbits & VPTE_A) { 2258 m = PHYS_TO_VM_PAGE(pbits & VPTE_FRAME); 2259 vm_page_flag_set(m, PG_REFERENCED); 2260 atomic_clear_long(pte, VPTE_A); 2261 } 2262 if (pbits & VPTE_M) { 2263 if (pmap_track_modified(pmap, sva)) { 2264 if (m == NULL) 2265 m = PHYS_TO_VM_PAGE(pbits & VPTE_FRAME); 2266 vm_page_dirty(m); 2267 } 2268 } 2269 } else { 2270 pbits = pmap_setro_pte(pte, pmap, sva); 2271 } 2272 } 2273 } 2274 lwkt_reltoken(&vm_token); 2275 } 2276 2277 /* 2278 * Enter a managed page into a pmap. If the page is not wired related pmap 2279 * data can be destroyed at any time for later demand-operation. 2280 * 2281 * Insert the vm_page (m) at virtual address (v) in (pmap), with the 2282 * specified protection, and wire the mapping if requested. 2283 * 2284 * NOTE: This routine may not lazy-evaluate or lose information. The 2285 * page must actually be inserted into the given map NOW. 2286 * 2287 * NOTE: When entering a page at a KVA address, the pmap must be the 2288 * kernel_pmap. 2289 * 2290 * No requirements. 2291 */ 2292 void 2293 pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 2294 boolean_t wired, vm_map_entry_t entry __unused) 2295 { 2296 vm_paddr_t pa; 2297 pd_entry_t *pde; 2298 pt_entry_t *pte; 2299 vm_paddr_t opa; 2300 pt_entry_t origpte, newpte; 2301 vm_page_t mpte; 2302 2303 if (pmap == NULL) 2304 return; 2305 2306 va = trunc_page(va); 2307 2308 vm_object_hold(pmap->pm_pteobj); 2309 lwkt_gettoken(&vm_token); 2310 2311 /* 2312 * Get the page table page. The kernel_pmap's page table pages 2313 * are preallocated and have no associated vm_page_t. 2314 */ 2315 if (pmap == &kernel_pmap) 2316 mpte = NULL; 2317 else 2318 mpte = pmap_allocpte(pmap, va); 2319 2320 pde = pmap_pde(pmap, va); 2321 if (pde != NULL && (*pde & VPTE_V) != 0) { 2322 if ((*pde & VPTE_PS) != 0) 2323 panic("pmap_enter: attempted pmap_enter on 2MB page"); 2324 pte = pmap_pde_to_pte(pde, va); 2325 } else { 2326 panic("pmap_enter: invalid page directory va=%#lx", va); 2327 } 2328 2329 KKASSERT(pte != NULL); 2330 /* 2331 * Deal with races on the original mapping (though don't worry 2332 * about VPTE_A races) by cleaning it. This will force a fault 2333 * if an attempt is made to write to the page. 2334 */ 2335 pa = VM_PAGE_TO_PHYS(m); 2336 origpte = pmap_clean_pte(pte, pmap, va); 2337 opa = origpte & VPTE_FRAME; 2338 2339 if (origpte & VPTE_PS) 2340 panic("pmap_enter: attempted pmap_enter on 2MB page"); 2341 2342 /* 2343 * Mapping has not changed, must be protection or wiring change. 2344 */ 2345 if (origpte && (opa == pa)) { 2346 /* 2347 * Wiring change, just update stats. We don't worry about 2348 * wiring PT pages as they remain resident as long as there 2349 * are valid mappings in them. Hence, if a user page is wired, 2350 * the PT page will be also. 2351 */ 2352 if (wired && ((origpte & VPTE_WIRED) == 0)) 2353 ++pmap->pm_stats.wired_count; 2354 else if (!wired && (origpte & VPTE_WIRED)) 2355 --pmap->pm_stats.wired_count; 2356 2357 /* 2358 * Remove the extra pte reference. Note that we cannot 2359 * optimize the RO->RW case because we have adjusted the 2360 * wiring count above and may need to adjust the wiring 2361 * bits below. 2362 */ 2363 if (mpte) 2364 mpte->hold_count--; 2365 2366 /* 2367 * We might be turning off write access to the page, 2368 * so we go ahead and sense modify status. 2369 */ 2370 if (origpte & VPTE_MANAGED) { 2371 if ((origpte & VPTE_M) && 2372 pmap_track_modified(pmap, va)) { 2373 vm_page_t om; 2374 om = PHYS_TO_VM_PAGE(opa); 2375 vm_page_dirty(om); 2376 } 2377 pa |= VPTE_MANAGED; 2378 KKASSERT(m->flags & PG_MAPPED); 2379 } 2380 goto validate; 2381 } 2382 /* 2383 * Mapping has changed, invalidate old range and fall through to 2384 * handle validating new mapping. 2385 */ 2386 if (opa) { 2387 int err; 2388 err = pmap_remove_pte(pmap, pte, va); 2389 if (err) 2390 panic("pmap_enter: pte vanished, va: 0x%lx", va); 2391 } 2392 2393 /* 2394 * Enter on the PV list if part of our managed memory. Note that we 2395 * raise IPL while manipulating pv_table since pmap_enter can be 2396 * called at interrupt time. 2397 */ 2398 if (pmap_initialized && 2399 (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2400 pmap_insert_entry(pmap, va, mpte, m); 2401 pa |= VPTE_MANAGED; 2402 vm_page_flag_set(m, PG_MAPPED); 2403 } 2404 2405 /* 2406 * Increment counters 2407 */ 2408 ++pmap->pm_stats.resident_count; 2409 if (wired) 2410 pmap->pm_stats.wired_count++; 2411 2412 validate: 2413 /* 2414 * Now validate mapping with desired protection/wiring. 2415 */ 2416 newpte = (pt_entry_t) (pa | pte_prot(pmap, prot) | VPTE_V | VPTE_U); 2417 2418 if (wired) 2419 newpte |= VPTE_WIRED; 2420 // if (pmap != &kernel_pmap) 2421 newpte |= VPTE_U; 2422 2423 /* 2424 * If the mapping or permission bits are different from the 2425 * (now cleaned) original pte, an update is needed. We've 2426 * already downgraded or invalidated the page so all we have 2427 * to do now is update the bits. 2428 * 2429 * XXX should we synchronize RO->RW changes to avoid another 2430 * fault? 2431 */ 2432 if ((origpte & ~(VPTE_RW|VPTE_M|VPTE_A)) != newpte) { 2433 *pte = newpte | VPTE_A; 2434 if (newpte & VPTE_RW) 2435 vm_page_flag_set(m, PG_WRITEABLE); 2436 } 2437 KKASSERT((newpte & VPTE_MANAGED) == 0 || (m->flags & PG_MAPPED)); 2438 lwkt_reltoken(&vm_token); 2439 vm_object_drop(pmap->pm_pteobj); 2440 } 2441 2442 /* 2443 * This code works like pmap_enter() but assumes VM_PROT_READ and not-wired. 2444 * 2445 * Currently this routine may only be used on user pmaps, not kernel_pmap. 2446 * 2447 * No requirements. 2448 */ 2449 void 2450 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m) 2451 { 2452 pt_entry_t *pte; 2453 vm_paddr_t pa; 2454 vm_page_t mpte; 2455 vm_pindex_t ptepindex; 2456 pd_entry_t *ptepa; 2457 2458 KKASSERT(pmap != &kernel_pmap); 2459 2460 KKASSERT(va >= VM_MIN_USER_ADDRESS && va < VM_MAX_USER_ADDRESS); 2461 2462 /* 2463 * Calculate pagetable page index 2464 */ 2465 ptepindex = pmap_pde_pindex(va); 2466 2467 vm_object_hold(pmap->pm_pteobj); 2468 lwkt_gettoken(&vm_token); 2469 2470 do { 2471 /* 2472 * Get the page directory entry 2473 */ 2474 ptepa = pmap_pde(pmap, va); 2475 2476 /* 2477 * If the page table page is mapped, we just increment 2478 * the hold count, and activate it. 2479 */ 2480 if (ptepa && (*ptepa & VPTE_V) != 0) { 2481 if (*ptepa & VPTE_PS) 2482 panic("pmap_enter_quick: unexpected mapping into 2MB page"); 2483 if (pmap->pm_ptphint && 2484 (pmap->pm_ptphint->pindex == ptepindex)) { 2485 mpte = pmap->pm_ptphint; 2486 } else { 2487 mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex); 2488 pmap->pm_ptphint = mpte; 2489 vm_page_wakeup(mpte); 2490 } 2491 if (mpte) 2492 mpte->hold_count++; 2493 } else { 2494 mpte = _pmap_allocpte(pmap, ptepindex); 2495 } 2496 } while (mpte == NULL); 2497 2498 /* 2499 * Ok, now that the page table page has been validated, get the pte. 2500 * If the pte is already mapped undo mpte's hold_count and 2501 * just return. 2502 */ 2503 pte = pmap_pte(pmap, va); 2504 if (*pte & VPTE_V) { 2505 KKASSERT(mpte != NULL); 2506 pmap_unwire_pte_hold(pmap, va, mpte); 2507 pa = VM_PAGE_TO_PHYS(m); 2508 KKASSERT(((*pte ^ pa) & VPTE_FRAME) == 0); 2509 lwkt_reltoken(&vm_token); 2510 vm_object_drop(pmap->pm_pteobj); 2511 return; 2512 } 2513 2514 /* 2515 * Enter on the PV list if part of our managed memory 2516 */ 2517 if ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) { 2518 pmap_insert_entry(pmap, va, mpte, m); 2519 vm_page_flag_set(m, PG_MAPPED); 2520 } 2521 2522 /* 2523 * Increment counters 2524 */ 2525 ++pmap->pm_stats.resident_count; 2526 2527 pa = VM_PAGE_TO_PHYS(m); 2528 2529 /* 2530 * Now validate mapping with RO protection 2531 */ 2532 if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) 2533 *pte = (vpte_t)pa | VPTE_V | VPTE_U; 2534 else 2535 *pte = (vpte_t)pa | VPTE_V | VPTE_U | VPTE_MANAGED; 2536 /*pmap_inval_add(&info, pmap, va); shouldn't be needed 0->valid */ 2537 /*pmap_inval_flush(&info); don't need for vkernel */ 2538 lwkt_reltoken(&vm_token); 2539 vm_object_drop(pmap->pm_pteobj); 2540 } 2541 2542 /* 2543 * Make a temporary mapping for a physical address. This is only intended 2544 * to be used for panic dumps. 2545 * 2546 * The caller is responsible for calling smp_invltlb(). 2547 */ 2548 void * 2549 pmap_kenter_temporary(vm_paddr_t pa, long i) 2550 { 2551 pmap_kenter_quick(crashdumpmap + (i * PAGE_SIZE), pa); 2552 return ((void *)crashdumpmap); 2553 } 2554 2555 #define MAX_INIT_PT (96) 2556 2557 /* 2558 * This routine preloads the ptes for a given object into the specified pmap. 2559 * This eliminates the blast of soft faults on process startup and 2560 * immediately after an mmap. 2561 * 2562 * No requirements. 2563 */ 2564 static int pmap_object_init_pt_callback(vm_page_t p, void *data); 2565 2566 void 2567 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, vm_prot_t prot, 2568 vm_object_t object, vm_pindex_t pindex, 2569 vm_size_t size, int limit) 2570 { 2571 struct rb_vm_page_scan_info info; 2572 struct lwp *lp; 2573 vm_size_t psize; 2574 2575 /* 2576 * We can't preinit if read access isn't set or there is no pmap 2577 * or object. 2578 */ 2579 if ((prot & VM_PROT_READ) == 0 || pmap == NULL || object == NULL) 2580 return; 2581 2582 /* 2583 * We can't preinit if the pmap is not the current pmap 2584 */ 2585 lp = curthread->td_lwp; 2586 if (lp == NULL || pmap != vmspace_pmap(lp->lwp_vmspace)) 2587 return; 2588 2589 psize = x86_64_btop(size); 2590 2591 if ((object->type != OBJT_VNODE) || 2592 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 2593 (object->resident_page_count > MAX_INIT_PT))) { 2594 return; 2595 } 2596 2597 if (psize + pindex > object->size) { 2598 if (object->size < pindex) 2599 return; 2600 psize = object->size - pindex; 2601 } 2602 2603 if (psize == 0) 2604 return; 2605 2606 /* 2607 * Use a red-black scan to traverse the requested range and load 2608 * any valid pages found into the pmap. 2609 * 2610 * We cannot safely scan the object's memq unless we are in a 2611 * critical section since interrupts can remove pages from objects. 2612 */ 2613 info.start_pindex = pindex; 2614 info.end_pindex = pindex + psize - 1; 2615 info.limit = limit; 2616 info.mpte = NULL; 2617 info.addr = addr; 2618 info.pmap = pmap; 2619 2620 vm_object_hold_shared(object); 2621 vm_page_rb_tree_RB_SCAN(&object->rb_memq, rb_vm_page_scancmp, 2622 pmap_object_init_pt_callback, &info); 2623 vm_object_drop(object); 2624 } 2625 2626 static 2627 int 2628 pmap_object_init_pt_callback(vm_page_t p, void *data) 2629 { 2630 struct rb_vm_page_scan_info *info = data; 2631 vm_pindex_t rel_index; 2632 /* 2633 * don't allow an madvise to blow away our really 2634 * free pages allocating pv entries. 2635 */ 2636 if ((info->limit & MAP_PREFAULT_MADVISE) && 2637 vmstats.v_free_count < vmstats.v_free_reserved) { 2638 return(-1); 2639 } 2640 2641 /* 2642 * Ignore list markers and ignore pages we cannot instantly 2643 * busy (while holding the object token). 2644 */ 2645 if (p->flags & PG_MARKER) 2646 return 0; 2647 if (vm_page_busy_try(p, TRUE)) 2648 return 0; 2649 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 2650 (p->flags & PG_FICTITIOUS) == 0) { 2651 if ((p->queue - p->pc) == PQ_CACHE) 2652 vm_page_deactivate(p); 2653 rel_index = p->pindex - info->start_pindex; 2654 pmap_enter_quick(info->pmap, 2655 info->addr + x86_64_ptob(rel_index), p); 2656 } 2657 vm_page_wakeup(p); 2658 return(0); 2659 } 2660 2661 /* 2662 * Return TRUE if the pmap is in shape to trivially 2663 * pre-fault the specified address. 2664 * 2665 * Returns FALSE if it would be non-trivial or if a 2666 * pte is already loaded into the slot. 2667 * 2668 * No requirements. 2669 */ 2670 int 2671 pmap_prefault_ok(pmap_t pmap, vm_offset_t addr) 2672 { 2673 pt_entry_t *pte; 2674 pd_entry_t *pde; 2675 int ret; 2676 2677 lwkt_gettoken(&vm_token); 2678 pde = pmap_pde(pmap, addr); 2679 if (pde == NULL || *pde == 0) { 2680 ret = 0; 2681 } else { 2682 pte = pmap_pde_to_pte(pde, addr); 2683 ret = (*pte) ? 0 : 1; 2684 } 2685 lwkt_reltoken(&vm_token); 2686 return (ret); 2687 } 2688 2689 /* 2690 * Change the wiring attribute for a map/virtual-address pair. 2691 * 2692 * The mapping must already exist in the pmap. 2693 * No other requirements. 2694 */ 2695 void 2696 pmap_change_wiring(pmap_t pmap, vm_offset_t va, boolean_t wired, 2697 vm_map_entry_t entry __unused) 2698 { 2699 pt_entry_t *pte; 2700 2701 if (pmap == NULL) 2702 return; 2703 2704 lwkt_gettoken(&vm_token); 2705 pte = pmap_pte(pmap, va); 2706 2707 if (wired && !pmap_pte_w(pte)) 2708 pmap->pm_stats.wired_count++; 2709 else if (!wired && pmap_pte_w(pte)) 2710 pmap->pm_stats.wired_count--; 2711 2712 /* 2713 * Wiring is not a hardware characteristic so there is no need to 2714 * invalidate TLB. However, in an SMP environment we must use 2715 * a locked bus cycle to update the pte (if we are not using 2716 * the pmap_inval_*() API that is)... it's ok to do this for simple 2717 * wiring changes. 2718 */ 2719 if (wired) 2720 atomic_set_long(pte, VPTE_WIRED); 2721 else 2722 atomic_clear_long(pte, VPTE_WIRED); 2723 lwkt_reltoken(&vm_token); 2724 } 2725 2726 /* 2727 * Copy the range specified by src_addr/len 2728 * from the source map to the range dst_addr/len 2729 * in the destination map. 2730 * 2731 * This routine is only advisory and need not do anything. 2732 */ 2733 void 2734 pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, 2735 vm_size_t len, vm_offset_t src_addr) 2736 { 2737 /* 2738 * XXX BUGGY. Amoung other things srcmpte is assumed to remain 2739 * valid through blocking calls, and that's just not going to 2740 * be the case. 2741 * 2742 * FIXME! 2743 */ 2744 return; 2745 } 2746 2747 /* 2748 * pmap_zero_page: 2749 * 2750 * Zero the specified physical page. 2751 * 2752 * This function may be called from an interrupt and no locking is 2753 * required. 2754 */ 2755 void 2756 pmap_zero_page(vm_paddr_t phys) 2757 { 2758 vm_offset_t va = PHYS_TO_DMAP(phys); 2759 2760 bzero((void *)va, PAGE_SIZE); 2761 } 2762 2763 /* 2764 * pmap_page_assertzero: 2765 * 2766 * Assert that a page is empty, panic if it isn't. 2767 */ 2768 void 2769 pmap_page_assertzero(vm_paddr_t phys) 2770 { 2771 int i; 2772 2773 crit_enter(); 2774 vm_offset_t virt = PHYS_TO_DMAP(phys); 2775 2776 for (i = 0; i < PAGE_SIZE; i += sizeof(int)) { 2777 if (*(int *)((char *)virt + i) != 0) { 2778 panic("pmap_page_assertzero() @ %p not zero!", 2779 (void *)virt); 2780 } 2781 } 2782 crit_exit(); 2783 } 2784 2785 /* 2786 * pmap_zero_page: 2787 * 2788 * Zero part of a physical page by mapping it into memory and clearing 2789 * its contents with bzero. 2790 * 2791 * off and size may not cover an area beyond a single hardware page. 2792 */ 2793 void 2794 pmap_zero_page_area(vm_paddr_t phys, int off, int size) 2795 { 2796 crit_enter(); 2797 vm_offset_t virt = PHYS_TO_DMAP(phys); 2798 bzero((char *)virt + off, size); 2799 crit_exit(); 2800 } 2801 2802 /* 2803 * pmap_copy_page: 2804 * 2805 * Copy the physical page from the source PA to the target PA. 2806 * This function may be called from an interrupt. No locking 2807 * is required. 2808 */ 2809 void 2810 pmap_copy_page(vm_paddr_t src, vm_paddr_t dst) 2811 { 2812 vm_offset_t src_virt, dst_virt; 2813 2814 crit_enter(); 2815 src_virt = PHYS_TO_DMAP(src); 2816 dst_virt = PHYS_TO_DMAP(dst); 2817 bcopy((void *)src_virt, (void *)dst_virt, PAGE_SIZE); 2818 crit_exit(); 2819 } 2820 2821 /* 2822 * pmap_copy_page_frag: 2823 * 2824 * Copy the physical page from the source PA to the target PA. 2825 * This function may be called from an interrupt. No locking 2826 * is required. 2827 */ 2828 void 2829 pmap_copy_page_frag(vm_paddr_t src, vm_paddr_t dst, size_t bytes) 2830 { 2831 vm_offset_t src_virt, dst_virt; 2832 2833 crit_enter(); 2834 src_virt = PHYS_TO_DMAP(src); 2835 dst_virt = PHYS_TO_DMAP(dst); 2836 bcopy((char *)src_virt + (src & PAGE_MASK), 2837 (char *)dst_virt + (dst & PAGE_MASK), 2838 bytes); 2839 crit_exit(); 2840 } 2841 2842 /* 2843 * Returns true if the pmap's pv is one of the first 16 pvs linked to 2844 * from this page. This count may be changed upwards or downwards 2845 * in the future; it is only necessary that true be returned for a small 2846 * subset of pmaps for proper page aging. 2847 * 2848 * No other requirements. 2849 */ 2850 boolean_t 2851 pmap_page_exists_quick(pmap_t pmap, vm_page_t m) 2852 { 2853 pv_entry_t pv; 2854 int loops = 0; 2855 2856 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2857 return FALSE; 2858 2859 crit_enter(); 2860 lwkt_gettoken(&vm_token); 2861 2862 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2863 if (pv->pv_pmap == pmap) { 2864 lwkt_reltoken(&vm_token); 2865 crit_exit(); 2866 return TRUE; 2867 } 2868 loops++; 2869 if (loops >= 16) 2870 break; 2871 } 2872 lwkt_reltoken(&vm_token); 2873 crit_exit(); 2874 return (FALSE); 2875 } 2876 2877 /* 2878 * Remove all pages from specified address space this aids process 2879 * exit speeds. Also, this code is special cased for current 2880 * process only, but can have the more generic (and slightly slower) 2881 * mode enabled. This is much faster than pmap_remove in the case 2882 * of running down an entire address space. 2883 * 2884 * No other requirements. 2885 */ 2886 void 2887 pmap_remove_pages(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 2888 { 2889 pt_entry_t *pte, tpte; 2890 pv_entry_t pv, npv; 2891 vm_page_t m; 2892 int save_generation; 2893 2894 if (pmap->pm_pteobj) 2895 vm_object_hold(pmap->pm_pteobj); 2896 lwkt_gettoken(&vm_token); 2897 2898 for (pv = TAILQ_FIRST(&pmap->pm_pvlist); pv; pv = npv) { 2899 if (pv->pv_va >= eva || pv->pv_va < sva) { 2900 npv = TAILQ_NEXT(pv, pv_plist); 2901 continue; 2902 } 2903 2904 KKASSERT(pmap == pv->pv_pmap); 2905 2906 pte = pmap_pte(pmap, pv->pv_va); 2907 2908 /* 2909 * We cannot remove wired pages from a process' mapping 2910 * at this time 2911 */ 2912 if (*pte & VPTE_WIRED) { 2913 npv = TAILQ_NEXT(pv, pv_plist); 2914 continue; 2915 } 2916 tpte = pmap_inval_loadandclear(pte, pmap, pv->pv_va); 2917 2918 m = PHYS_TO_VM_PAGE(tpte & VPTE_FRAME); 2919 2920 KASSERT(m < &vm_page_array[vm_page_array_size], 2921 ("pmap_remove_pages: bad tpte %lx", tpte)); 2922 2923 KKASSERT(pmap->pm_stats.resident_count > 0); 2924 --pmap->pm_stats.resident_count; 2925 2926 /* 2927 * Update the vm_page_t clean and reference bits. 2928 */ 2929 if (tpte & VPTE_M) { 2930 vm_page_dirty(m); 2931 } 2932 2933 npv = TAILQ_NEXT(pv, pv_plist); 2934 TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist); 2935 save_generation = ++pmap->pm_generation; 2936 2937 m->md.pv_list_count--; 2938 atomic_add_int(&m->object->agg_pv_list_count, -1); 2939 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 2940 if (TAILQ_EMPTY(&m->md.pv_list)) 2941 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 2942 2943 pmap_unuse_pt(pmap, pv->pv_va, pv->pv_ptem); 2944 free_pv_entry(pv); 2945 2946 /* 2947 * Restart the scan if we blocked during the unuse or free 2948 * calls and other removals were made. 2949 */ 2950 if (save_generation != pmap->pm_generation) { 2951 kprintf("Warning: pmap_remove_pages race-A avoided\n"); 2952 npv = TAILQ_FIRST(&pmap->pm_pvlist); 2953 } 2954 } 2955 lwkt_reltoken(&vm_token); 2956 if (pmap->pm_pteobj) 2957 vm_object_drop(pmap->pm_pteobj); 2958 } 2959 2960 /* 2961 * pmap_testbit tests bits in active mappings of a VM page. 2962 */ 2963 static boolean_t 2964 pmap_testbit(vm_page_t m, int bit) 2965 { 2966 pv_entry_t pv; 2967 pt_entry_t *pte; 2968 2969 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 2970 return FALSE; 2971 2972 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 2973 return FALSE; 2974 2975 crit_enter(); 2976 2977 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 2978 /* 2979 * if the bit being tested is the modified bit, then 2980 * mark clean_map and ptes as never 2981 * modified. 2982 */ 2983 if (bit & (VPTE_A|VPTE_M)) { 2984 if (!pmap_track_modified(pv->pv_pmap, pv->pv_va)) 2985 continue; 2986 } 2987 2988 #if defined(PMAP_DIAGNOSTIC) 2989 if (pv->pv_pmap == NULL) { 2990 kprintf("Null pmap (tb) at va: 0x%lx\n", pv->pv_va); 2991 continue; 2992 } 2993 #endif 2994 pte = pmap_pte(pv->pv_pmap, pv->pv_va); 2995 if (*pte & bit) { 2996 crit_exit(); 2997 return TRUE; 2998 } 2999 } 3000 crit_exit(); 3001 return (FALSE); 3002 } 3003 3004 /* 3005 * This routine is used to clear bits in ptes. Certain bits require special 3006 * handling, in particular (on virtual kernels) the VPTE_M (modify) bit. 3007 * 3008 * This routine is only called with certain VPTE_* bit combinations. 3009 */ 3010 static __inline void 3011 pmap_clearbit(vm_page_t m, int bit) 3012 { 3013 pv_entry_t pv; 3014 pt_entry_t *pte; 3015 pt_entry_t pbits; 3016 3017 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3018 return; 3019 3020 crit_enter(); 3021 3022 /* 3023 * Loop over all current mappings setting/clearing as appropos If 3024 * setting RO do we need to clear the VAC? 3025 */ 3026 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 3027 /* 3028 * don't write protect pager mappings 3029 */ 3030 if (bit == VPTE_RW) { 3031 if (!pmap_track_modified(pv->pv_pmap, pv->pv_va)) 3032 continue; 3033 } 3034 3035 #if defined(PMAP_DIAGNOSTIC) 3036 if (pv->pv_pmap == NULL) { 3037 kprintf("Null pmap (cb) at va: 0x%lx\n", pv->pv_va); 3038 continue; 3039 } 3040 #endif 3041 3042 /* 3043 * Careful here. We can use a locked bus instruction to 3044 * clear VPTE_A or VPTE_M safely but we need to synchronize 3045 * with the target cpus when we mess with VPTE_RW. 3046 * 3047 * On virtual kernels we must force a new fault-on-write 3048 * in the real kernel if we clear the Modify bit ourselves, 3049 * otherwise the real kernel will not get a new fault and 3050 * will never set our Modify bit again. 3051 */ 3052 pte = pmap_pte(pv->pv_pmap, pv->pv_va); 3053 if (*pte & bit) { 3054 if (bit == VPTE_RW) { 3055 /* 3056 * We must also clear VPTE_M when clearing 3057 * VPTE_RW 3058 */ 3059 pbits = pmap_clean_pte(pte, pv->pv_pmap, 3060 pv->pv_va); 3061 if (pbits & VPTE_M) 3062 vm_page_dirty(m); 3063 } else if (bit == VPTE_M) { 3064 /* 3065 * We do not have to make the page read-only 3066 * when clearing the Modify bit. The real 3067 * kernel will make the real PTE read-only 3068 * or otherwise detect the write and set 3069 * our VPTE_M again simply by us invalidating 3070 * the real kernel VA for the pmap (as we did 3071 * above). This allows the real kernel to 3072 * handle the write fault without forwarding 3073 * the fault to us. 3074 */ 3075 atomic_clear_long(pte, VPTE_M); 3076 } else if ((bit & (VPTE_RW|VPTE_M)) == (VPTE_RW|VPTE_M)) { 3077 /* 3078 * We've been asked to clear W & M, I guess 3079 * the caller doesn't want us to update 3080 * the dirty status of the VM page. 3081 */ 3082 pmap_clean_pte(pte, pv->pv_pmap, pv->pv_va); 3083 } else { 3084 /* 3085 * We've been asked to clear bits that do 3086 * not interact with hardware. 3087 */ 3088 atomic_clear_long(pte, bit); 3089 } 3090 } 3091 } 3092 crit_exit(); 3093 } 3094 3095 /* 3096 * Lower the permission for all mappings to a given page. 3097 * 3098 * No other requirements. 3099 */ 3100 void 3101 pmap_page_protect(vm_page_t m, vm_prot_t prot) 3102 { 3103 /* JG NX support? */ 3104 if ((prot & VM_PROT_WRITE) == 0) { 3105 lwkt_gettoken(&vm_token); 3106 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 3107 pmap_clearbit(m, VPTE_RW); 3108 vm_page_flag_clear(m, PG_WRITEABLE); 3109 } else { 3110 pmap_remove_all(m); 3111 } 3112 lwkt_reltoken(&vm_token); 3113 } 3114 } 3115 3116 vm_paddr_t 3117 pmap_phys_address(vm_pindex_t ppn) 3118 { 3119 return (x86_64_ptob(ppn)); 3120 } 3121 3122 /* 3123 * Return a count of reference bits for a page, clearing those bits. 3124 * It is not necessary for every reference bit to be cleared, but it 3125 * is necessary that 0 only be returned when there are truly no 3126 * reference bits set. 3127 * 3128 * XXX: The exact number of bits to check and clear is a matter that 3129 * should be tested and standardized at some point in the future for 3130 * optimal aging of shared pages. 3131 * 3132 * No other requirements. 3133 */ 3134 int 3135 pmap_ts_referenced(vm_page_t m) 3136 { 3137 pv_entry_t pv, pvf, pvn; 3138 pt_entry_t *pte; 3139 int rtval = 0; 3140 3141 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 3142 return (rtval); 3143 3144 crit_enter(); 3145 lwkt_gettoken(&vm_token); 3146 3147 if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 3148 3149 pvf = pv; 3150 3151 do { 3152 pvn = TAILQ_NEXT(pv, pv_list); 3153 3154 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3155 3156 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 3157 3158 if (!pmap_track_modified(pv->pv_pmap, pv->pv_va)) 3159 continue; 3160 3161 pte = pmap_pte(pv->pv_pmap, pv->pv_va); 3162 3163 if (pte && (*pte & VPTE_A)) { 3164 atomic_clear_long(pte, VPTE_A); 3165 rtval++; 3166 if (rtval > 4) { 3167 break; 3168 } 3169 } 3170 } while ((pv = pvn) != NULL && pv != pvf); 3171 } 3172 lwkt_reltoken(&vm_token); 3173 crit_exit(); 3174 3175 return (rtval); 3176 } 3177 3178 /* 3179 * Return whether or not the specified physical page was modified 3180 * in any physical maps. 3181 * 3182 * No other requirements. 3183 */ 3184 boolean_t 3185 pmap_is_modified(vm_page_t m) 3186 { 3187 boolean_t res; 3188 3189 lwkt_gettoken(&vm_token); 3190 res = pmap_testbit(m, VPTE_M); 3191 lwkt_reltoken(&vm_token); 3192 return (res); 3193 } 3194 3195 /* 3196 * Clear the modify bits on the specified physical page. 3197 * 3198 * No other requirements. 3199 */ 3200 void 3201 pmap_clear_modify(vm_page_t m) 3202 { 3203 lwkt_gettoken(&vm_token); 3204 pmap_clearbit(m, VPTE_M); 3205 lwkt_reltoken(&vm_token); 3206 } 3207 3208 /* 3209 * Clear the reference bit on the specified physical page. 3210 * 3211 * No other requirements. 3212 */ 3213 void 3214 pmap_clear_reference(vm_page_t m) 3215 { 3216 lwkt_gettoken(&vm_token); 3217 pmap_clearbit(m, VPTE_A); 3218 lwkt_reltoken(&vm_token); 3219 } 3220 3221 /* 3222 * Miscellaneous support routines follow 3223 */ 3224 3225 static void 3226 i386_protection_init(void) 3227 { 3228 int *kp, prot; 3229 3230 kp = protection_codes; 3231 for (prot = 0; prot < 8; prot++) { 3232 if (prot & VM_PROT_READ) 3233 *kp |= 0; /* if it's VALID is readeable */ 3234 if (prot & VM_PROT_WRITE) 3235 *kp |= VPTE_RW; 3236 if (prot & VM_PROT_EXECUTE) 3237 *kp |= 0; /* if it's VALID is executable */ 3238 ++kp; 3239 } 3240 } 3241 3242 /* 3243 * Sets the memory attribute for the specified page. 3244 */ 3245 void 3246 pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma) 3247 { 3248 /* This is a vkernel, do nothing */ 3249 } 3250 3251 /* 3252 * Change the PAT attribute on an existing kernel memory map. Caller 3253 * must ensure that the virtual memory in question is not accessed 3254 * during the adjustment. 3255 */ 3256 void 3257 pmap_change_attr(vm_offset_t va, vm_size_t count, int mode) 3258 { 3259 /* This is a vkernel, do nothing */ 3260 } 3261 3262 /* 3263 * Perform the pmap work for mincore 3264 * 3265 * No other requirements. 3266 */ 3267 int 3268 pmap_mincore(pmap_t pmap, vm_offset_t addr) 3269 { 3270 pt_entry_t *ptep, pte; 3271 vm_page_t m; 3272 int val = 0; 3273 3274 lwkt_gettoken(&vm_token); 3275 ptep = pmap_pte(pmap, addr); 3276 3277 if (ptep && (pte = *ptep) != 0) { 3278 vm_paddr_t pa; 3279 3280 val = MINCORE_INCORE; 3281 if ((pte & VPTE_MANAGED) == 0) 3282 goto done; 3283 3284 pa = pte & VPTE_FRAME; 3285 3286 m = PHYS_TO_VM_PAGE(pa); 3287 3288 /* 3289 * Modified by us 3290 */ 3291 if (pte & VPTE_M) 3292 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 3293 /* 3294 * Modified by someone 3295 */ 3296 else if (m->dirty || pmap_is_modified(m)) 3297 val |= MINCORE_MODIFIED_OTHER; 3298 /* 3299 * Referenced by us 3300 */ 3301 if (pte & VPTE_A) 3302 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 3303 3304 /* 3305 * Referenced by someone 3306 */ 3307 else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) { 3308 val |= MINCORE_REFERENCED_OTHER; 3309 vm_page_flag_set(m, PG_REFERENCED); 3310 } 3311 } 3312 done: 3313 lwkt_reltoken(&vm_token); 3314 return val; 3315 } 3316 3317 /* 3318 * Replace p->p_vmspace with a new one. If adjrefs is non-zero the new 3319 * vmspace will be ref'd and the old one will be deref'd. 3320 * 3321 * Caller must hold vmspace->vm_map.token for oldvm and newvm 3322 */ 3323 void 3324 pmap_replacevm(struct proc *p, struct vmspace *newvm, int adjrefs) 3325 { 3326 struct vmspace *oldvm; 3327 struct lwp *lp; 3328 3329 crit_enter(); 3330 oldvm = p->p_vmspace; 3331 if (oldvm != newvm) { 3332 p->p_vmspace = newvm; 3333 KKASSERT(p->p_nthreads == 1); 3334 lp = RB_ROOT(&p->p_lwp_tree); 3335 pmap_setlwpvm(lp, newvm); 3336 if (adjrefs) { 3337 vmspace_ref(newvm); 3338 vmspace_rel(oldvm); 3339 } 3340 } 3341 crit_exit(); 3342 } 3343 3344 /* 3345 * Set the vmspace for a LWP. The vmspace is almost universally set the 3346 * same as the process vmspace, but virtual kernels need to swap out contexts 3347 * on a per-lwp basis. 3348 */ 3349 void 3350 pmap_setlwpvm(struct lwp *lp, struct vmspace *newvm) 3351 { 3352 struct vmspace *oldvm; 3353 struct pmap *pmap; 3354 3355 oldvm = lp->lwp_vmspace; 3356 if (oldvm == newvm) 3357 return; 3358 lp->lwp_vmspace = newvm; 3359 if (curthread->td_lwp != lp) 3360 return; 3361 /* 3362 * NOTE: We don't have to worry about the CPULOCK here because 3363 * the virtual kernel doesn't call this function when VMM 3364 * is enabled (and depends on the host kernel when it isn't). 3365 */ 3366 crit_enter(); 3367 pmap = vmspace_pmap(newvm); 3368 ATOMIC_CPUMASK_ORBIT(pmap->pm_active, mycpu->gd_cpuid); 3369 #if defined(SWTCH_OPTIM_STATS) 3370 tlb_flush_count++; 3371 #endif 3372 pmap = vmspace_pmap(oldvm); 3373 ATOMIC_CPUMASK_NANDBIT(pmap->pm_active, mycpu->gd_cpuid); 3374 crit_exit(); 3375 } 3376 3377 /* 3378 * The swtch code tried to switch in a heavy weight process whos pmap 3379 * is locked by another cpu. We have to wait for the lock to clear before 3380 * the pmap can be used. 3381 */ 3382 void 3383 pmap_interlock_wait (struct vmspace *vm) 3384 { 3385 pmap_t pmap = vmspace_pmap(vm); 3386 3387 while (pmap->pm_active_lock & CPULOCK_EXCL) 3388 pthread_yield(); 3389 } 3390 3391 vm_offset_t 3392 pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 3393 { 3394 3395 if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) { 3396 return addr; 3397 } 3398 3399 addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1); 3400 return addr; 3401 } 3402 3403 /* 3404 * Used by kmalloc/kfree, page already exists at va 3405 */ 3406 vm_page_t 3407 pmap_kvtom(vm_offset_t va) 3408 { 3409 vpte_t *ptep; 3410 3411 KKASSERT(va >= KvaStart && va < KvaEnd); 3412 ptep = vtopte(va); 3413 return(PHYS_TO_VM_PAGE(*ptep & PG_FRAME)); 3414 } 3415 3416 void 3417 pmap_object_init(vm_object_t object) 3418 { 3419 /* empty */ 3420 } 3421 3422 void 3423 pmap_object_free(vm_object_t object) 3424 { 3425 /* empty */ 3426 } 3427