1 /* 2 * Copyright (c) 1991 Regents of the University of California. 3 * Copyright (c) 1994 John S. Dyson 4 * Copyright (c) 1994 David Greenman 5 * Copyright (c) 2003 Peter Wemm 6 * Copyright (c) 2005-2008 Alan L. Cox <alc@cs.rice.edu> 7 * Copyright (c) 2008, 2009 The DragonFly Project. 8 * Copyright (c) 2008, 2009 Jordan Gordeev. 9 * Copyright (c) 2011-2017 Matthew Dillon 10 * All rights reserved. 11 * 12 * This code is derived from software contributed to Berkeley by 13 * the Systems Programming Group of the University of Utah Computer 14 * Science Department and William Jolitz of UUNET Technologies Inc. 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 1. Redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer. 21 * 2. Redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution. 24 * 3. All advertising materials mentioning features or use of this software 25 * must display the following acknowledgement: 26 * This product includes software developed by the University of 27 * California, Berkeley and its contributors. 28 * 4. Neither the name of the University nor the names of its contributors 29 * may be used to endorse or promote products derived from this software 30 * without specific prior written permission. 31 * 32 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 33 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 34 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 35 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 36 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 40 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 41 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 42 * SUCH DAMAGE. 43 */ 44 /* 45 * Manage physical address maps for x86-64 systems. 46 */ 47 48 #if 0 /* JG */ 49 #include "opt_pmap.h" 50 #endif 51 #include "opt_msgbuf.h" 52 53 #include <sys/param.h> 54 #include <sys/kernel.h> 55 #include <sys/proc.h> 56 #include <sys/msgbuf.h> 57 #include <sys/vmmeter.h> 58 #include <sys/mman.h> 59 #include <sys/systm.h> 60 61 #include <vm/vm.h> 62 #include <vm/vm_param.h> 63 #include <sys/sysctl.h> 64 #include <sys/lock.h> 65 #include <vm/vm_kern.h> 66 #include <vm/vm_page.h> 67 #include <vm/vm_map.h> 68 #include <vm/vm_object.h> 69 #include <vm/vm_extern.h> 70 #include <vm/vm_pageout.h> 71 #include <vm/vm_pager.h> 72 #include <vm/vm_zone.h> 73 74 #include <sys/user.h> 75 #include <sys/thread2.h> 76 #include <sys/spinlock2.h> 77 #include <vm/vm_page2.h> 78 79 #include <machine/cputypes.h> 80 #include <machine/md_var.h> 81 #include <machine/specialreg.h> 82 #include <machine/smp.h> 83 #include <machine_base/apic/apicreg.h> 84 #include <machine/globaldata.h> 85 #include <machine/pmap.h> 86 #include <machine/pmap_inval.h> 87 #include <machine/inttypes.h> 88 89 #include <ddb/ddb.h> 90 91 #define PMAP_KEEP_PDIRS 92 #ifndef PMAP_SHPGPERPROC 93 #define PMAP_SHPGPERPROC 2000 94 #endif 95 96 #if defined(DIAGNOSTIC) 97 #define PMAP_DIAGNOSTIC 98 #endif 99 100 #define MINPV 2048 101 102 /* 103 * pmap debugging will report who owns a pv lock when blocking. 104 */ 105 #ifdef PMAP_DEBUG 106 107 #define PMAP_DEBUG_DECL ,const char *func, int lineno 108 #define PMAP_DEBUG_ARGS , __func__, __LINE__ 109 #define PMAP_DEBUG_COPY , func, lineno 110 111 #define pv_get(pmap, pindex, pmarkp) _pv_get(pmap, pindex, pmarkp \ 112 PMAP_DEBUG_ARGS) 113 #define pv_lock(pv) _pv_lock(pv \ 114 PMAP_DEBUG_ARGS) 115 #define pv_hold_try(pv) _pv_hold_try(pv \ 116 PMAP_DEBUG_ARGS) 117 #define pv_alloc(pmap, pindex, isnewp) _pv_alloc(pmap, pindex, isnewp \ 118 PMAP_DEBUG_ARGS) 119 120 #define pv_free(pv, pvp) _pv_free(pv, pvp PMAP_DEBUG_ARGS) 121 122 #else 123 124 #define PMAP_DEBUG_DECL 125 #define PMAP_DEBUG_ARGS 126 #define PMAP_DEBUG_COPY 127 128 #define pv_get(pmap, pindex, pmarkp) _pv_get(pmap, pindex, pmarkp) 129 #define pv_lock(pv) _pv_lock(pv) 130 #define pv_hold_try(pv) _pv_hold_try(pv) 131 #define pv_alloc(pmap, pindex, isnewp) _pv_alloc(pmap, pindex, isnewp) 132 #define pv_free(pv, pvp) _pv_free(pv, pvp) 133 134 #endif 135 136 /* 137 * Get PDEs and PTEs for user/kernel address space 138 */ 139 #define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT]) 140 141 #define pmap_pde_v(pmap, pte) ((*(pd_entry_t *)pte & pmap->pmap_bits[PG_V_IDX]) != 0) 142 #define pmap_pte_w(pmap, pte) ((*(pt_entry_t *)pte & pmap->pmap_bits[PG_W_IDX]) != 0) 143 #define pmap_pte_m(pmap, pte) ((*(pt_entry_t *)pte & pmap->pmap_bits[PG_M_IDX]) != 0) 144 #define pmap_pte_u(pmap, pte) ((*(pt_entry_t *)pte & pmap->pmap_bits[PG_U_IDX]) != 0) 145 #define pmap_pte_v(pmap, pte) ((*(pt_entry_t *)pte & pmap->pmap_bits[PG_V_IDX]) != 0) 146 147 /* 148 * Given a map and a machine independent protection code, 149 * convert to a vax protection code. 150 */ 151 #define pte_prot(m, p) \ 152 (m->protection_codes[p & (VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE)]) 153 static uint64_t protection_codes[PROTECTION_CODES_SIZE]; 154 155 struct pmap kernel_pmap; 156 157 MALLOC_DEFINE(M_OBJPMAP, "objpmap", "pmaps associated with VM objects"); 158 159 vm_paddr_t avail_start; /* PA of first available physical page */ 160 vm_paddr_t avail_end; /* PA of last available physical page */ 161 vm_offset_t virtual2_start; /* cutout free area prior to kernel start */ 162 vm_offset_t virtual2_end; 163 vm_offset_t virtual_start; /* VA of first avail page (after kernel bss) */ 164 vm_offset_t virtual_end; /* VA of last avail page (end of kernel AS) */ 165 vm_offset_t KvaStart; /* VA start of KVA space */ 166 vm_offset_t KvaEnd; /* VA end of KVA space (non-inclusive) */ 167 vm_offset_t KvaSize; /* max size of kernel virtual address space */ 168 static boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */ 169 //static int pgeflag; /* PG_G or-in */ 170 uint64_t PatMsr; 171 172 static int ndmpdp; 173 static vm_paddr_t dmaplimit; 174 vm_offset_t kernel_vm_end = VM_MIN_KERNEL_ADDRESS; 175 176 static pt_entry_t pat_pte_index[PAT_INDEX_SIZE]; /* PAT -> PG_ bits */ 177 /*static pt_entry_t pat_pde_index[PAT_INDEX_SIZE];*/ /* PAT -> PG_ bits */ 178 179 static uint64_t KPTbase; 180 static uint64_t KPTphys; 181 static uint64_t KPDphys; /* phys addr of kernel level 2 */ 182 static uint64_t KPDbase; /* phys addr of kernel level 2 @ KERNBASE */ 183 uint64_t KPDPphys; /* phys addr of kernel level 3 */ 184 uint64_t KPML4phys; /* phys addr of kernel level 4 */ 185 186 static uint64_t DMPDphys; /* phys addr of direct mapped level 2 */ 187 static uint64_t DMPDPphys; /* phys addr of direct mapped level 3 */ 188 189 /* 190 * Data for the pv entry allocation mechanism 191 */ 192 static vm_zone_t pvzone; 193 static struct vm_zone pvzone_store; 194 static vm_pindex_t pv_entry_max=0, pv_entry_high_water=0; 195 static int pmap_pagedaemon_waken = 0; 196 static struct pv_entry *pvinit; 197 198 /* 199 * All those kernel PT submaps that BSD is so fond of 200 */ 201 pt_entry_t *CMAP1 = NULL, *ptmmap; 202 caddr_t CADDR1 = NULL, ptvmmap = NULL; 203 static pt_entry_t *msgbufmap; 204 struct msgbuf *msgbufp=NULL; 205 206 /* 207 * PMAP default PG_* bits. Needed to be able to add 208 * EPT/NPT pagetable pmap_bits for the VMM module 209 */ 210 uint64_t pmap_bits_default[] = { 211 REGULAR_PMAP, /* TYPE_IDX 0 */ 212 X86_PG_V, /* PG_V_IDX 1 */ 213 X86_PG_RW, /* PG_RW_IDX 2 */ 214 X86_PG_U, /* PG_U_IDX 3 */ 215 X86_PG_A, /* PG_A_IDX 4 */ 216 X86_PG_M, /* PG_M_IDX 5 */ 217 X86_PG_PS, /* PG_PS_IDX3 6 */ 218 X86_PG_G, /* PG_G_IDX 7 */ 219 X86_PG_AVAIL1, /* PG_AVAIL1_IDX 8 */ 220 X86_PG_AVAIL2, /* PG_AVAIL2_IDX 9 */ 221 X86_PG_AVAIL3, /* PG_AVAIL3_IDX 10 */ 222 X86_PG_NC_PWT | X86_PG_NC_PCD, /* PG_N_IDX 11 */ 223 X86_PG_NX, /* PG_NX_IDX 12 */ 224 }; 225 /* 226 * Crashdump maps. 227 */ 228 static pt_entry_t *pt_crashdumpmap; 229 static caddr_t crashdumpmap; 230 231 static int pmap_debug = 0; 232 SYSCTL_INT(_machdep, OID_AUTO, pmap_debug, CTLFLAG_RW, 233 &pmap_debug, 0, "Debug pmap's"); 234 #ifdef PMAP_DEBUG2 235 static int pmap_enter_debug = 0; 236 SYSCTL_INT(_machdep, OID_AUTO, pmap_enter_debug, CTLFLAG_RW, 237 &pmap_enter_debug, 0, "Debug pmap_enter's"); 238 #endif 239 static int pmap_yield_count = 64; 240 SYSCTL_INT(_machdep, OID_AUTO, pmap_yield_count, CTLFLAG_RW, 241 &pmap_yield_count, 0, "Yield during init_pt/release"); 242 static int pmap_mmu_optimize = 0; 243 SYSCTL_INT(_machdep, OID_AUTO, pmap_mmu_optimize, CTLFLAG_RW, 244 &pmap_mmu_optimize, 0, "Share page table pages when possible"); 245 int pmap_fast_kernel_cpusync = 0; 246 SYSCTL_INT(_machdep, OID_AUTO, pmap_fast_kernel_cpusync, CTLFLAG_RW, 247 &pmap_fast_kernel_cpusync, 0, "Share page table pages when possible"); 248 int pmap_dynamic_delete = 0; 249 SYSCTL_INT(_machdep, OID_AUTO, pmap_dynamic_delete, CTLFLAG_RW, 250 &pmap_dynamic_delete, 0, "Dynamically delete PT/PD/PDPs"); 251 int pmap_lock_delay = 100; 252 SYSCTL_INT(_machdep, OID_AUTO, pmap_lock_delay, CTLFLAG_RW, 253 &pmap_lock_delay, 0, "Spin loops"); 254 255 static int pmap_nx_enable = 0; 256 /* needs manual TUNABLE in early probe, see below */ 257 258 /* Standard user access funtions */ 259 extern int std_copyinstr (const void *udaddr, void *kaddr, size_t len, 260 size_t *lencopied); 261 extern int std_copyin (const void *udaddr, void *kaddr, size_t len); 262 extern int std_copyout (const void *kaddr, void *udaddr, size_t len); 263 extern int std_fubyte (const uint8_t *base); 264 extern int std_subyte (uint8_t *base, uint8_t byte); 265 extern int32_t std_fuword32 (const uint32_t *base); 266 extern int64_t std_fuword64 (const uint64_t *base); 267 extern int std_suword64 (uint64_t *base, uint64_t word); 268 extern int std_suword32 (uint32_t *base, int word); 269 extern uint32_t std_swapu32 (volatile uint32_t *base, uint32_t v); 270 extern uint64_t std_swapu64 (volatile uint64_t *base, uint64_t v); 271 272 static void pv_hold(pv_entry_t pv); 273 static int _pv_hold_try(pv_entry_t pv 274 PMAP_DEBUG_DECL); 275 static void pv_drop(pv_entry_t pv); 276 static void _pv_lock(pv_entry_t pv 277 PMAP_DEBUG_DECL); 278 static void pv_unlock(pv_entry_t pv); 279 static pv_entry_t _pv_alloc(pmap_t pmap, vm_pindex_t pindex, int *isnew 280 PMAP_DEBUG_DECL); 281 static pv_entry_t _pv_get(pmap_t pmap, vm_pindex_t pindex, vm_pindex_t **pmarkp 282 PMAP_DEBUG_DECL); 283 static void _pv_free(pv_entry_t pv, pv_entry_t pvp PMAP_DEBUG_DECL); 284 static pv_entry_t pv_get_try(pmap_t pmap, vm_pindex_t pindex, 285 vm_pindex_t **pmarkp, int *errorp); 286 static void pv_put(pv_entry_t pv); 287 static void *pv_pte_lookup(pv_entry_t pv, vm_pindex_t pindex); 288 static pv_entry_t pmap_allocpte(pmap_t pmap, vm_pindex_t ptepindex, 289 pv_entry_t *pvpp); 290 static pv_entry_t pmap_allocpte_seg(pmap_t pmap, vm_pindex_t ptepindex, 291 pv_entry_t *pvpp, vm_map_entry_t entry, vm_offset_t va); 292 static void pmap_remove_pv_pte(pv_entry_t pv, pv_entry_t pvp, 293 pmap_inval_bulk_t *bulk, int destroy); 294 static vm_page_t pmap_remove_pv_page(pv_entry_t pv); 295 static int pmap_release_pv(pv_entry_t pv, pv_entry_t pvp, 296 pmap_inval_bulk_t *bulk); 297 298 struct pmap_scan_info; 299 static void pmap_remove_callback(pmap_t pmap, struct pmap_scan_info *info, 300 pv_entry_t pte_pv, vm_pindex_t *pte_placemark, 301 pv_entry_t pt_pv, int sharept, 302 vm_offset_t va, pt_entry_t *ptep, void *arg __unused); 303 static void pmap_protect_callback(pmap_t pmap, struct pmap_scan_info *info, 304 pv_entry_t pte_pv, vm_pindex_t *pte_placemark, 305 pv_entry_t pt_pv, int sharept, 306 vm_offset_t va, pt_entry_t *ptep, void *arg __unused); 307 308 static void i386_protection_init (void); 309 static void create_pagetables(vm_paddr_t *firstaddr); 310 static void pmap_remove_all (vm_page_t m); 311 static boolean_t pmap_testbit (vm_page_t m, int bit); 312 313 static pt_entry_t * pmap_pte_quick (pmap_t pmap, vm_offset_t va); 314 static vm_offset_t pmap_kmem_choose(vm_offset_t addr); 315 316 static void pmap_pinit_defaults(struct pmap *pmap); 317 static void pv_placemarker_wait(pmap_t pmap, vm_pindex_t *pmark); 318 static void pv_placemarker_wakeup(pmap_t pmap, vm_pindex_t *pmark); 319 320 static int 321 pv_entry_compare(pv_entry_t pv1, pv_entry_t pv2) 322 { 323 if (pv1->pv_pindex < pv2->pv_pindex) 324 return(-1); 325 if (pv1->pv_pindex > pv2->pv_pindex) 326 return(1); 327 return(0); 328 } 329 330 RB_GENERATE2(pv_entry_rb_tree, pv_entry, pv_entry, 331 pv_entry_compare, vm_pindex_t, pv_pindex); 332 333 static __inline 334 void 335 pmap_page_stats_adding(vm_page_t m) 336 { 337 globaldata_t gd = mycpu; 338 339 if (TAILQ_EMPTY(&m->md.pv_list)) { 340 ++gd->gd_vmtotal.t_arm; 341 } else if (TAILQ_FIRST(&m->md.pv_list) == 342 TAILQ_LAST(&m->md.pv_list, md_page_pv_list)) { 343 ++gd->gd_vmtotal.t_armshr; 344 ++gd->gd_vmtotal.t_avmshr; 345 } else { 346 ++gd->gd_vmtotal.t_avmshr; 347 } 348 } 349 350 static __inline 351 void 352 pmap_page_stats_deleting(vm_page_t m) 353 { 354 globaldata_t gd = mycpu; 355 356 if (TAILQ_EMPTY(&m->md.pv_list)) { 357 --gd->gd_vmtotal.t_arm; 358 } else if (TAILQ_FIRST(&m->md.pv_list) == 359 TAILQ_LAST(&m->md.pv_list, md_page_pv_list)) { 360 --gd->gd_vmtotal.t_armshr; 361 --gd->gd_vmtotal.t_avmshr; 362 } else { 363 --gd->gd_vmtotal.t_avmshr; 364 } 365 } 366 367 /* 368 * This is an ineligent crowbar to prevent heavily threaded programs 369 * from creating long live-locks in the pmap code when pmap_mmu_optimize 370 * is enabled. Without it a pmap-local page table page can wind up being 371 * constantly created and destroyed (without injury, but also without 372 * progress) as the optimization tries to switch to the object's shared page 373 * table page. 374 */ 375 static __inline void 376 pmap_softwait(pmap_t pmap) 377 { 378 while (pmap->pm_softhold) { 379 tsleep_interlock(&pmap->pm_softhold, 0); 380 if (pmap->pm_softhold) 381 tsleep(&pmap->pm_softhold, PINTERLOCKED, "mmopt", 0); 382 } 383 } 384 385 static __inline void 386 pmap_softhold(pmap_t pmap) 387 { 388 while (atomic_swap_int(&pmap->pm_softhold, 1) == 1) { 389 tsleep_interlock(&pmap->pm_softhold, 0); 390 if (atomic_swap_int(&pmap->pm_softhold, 1) == 1) 391 tsleep(&pmap->pm_softhold, PINTERLOCKED, "mmopt", 0); 392 } 393 } 394 395 static __inline void 396 pmap_softdone(pmap_t pmap) 397 { 398 atomic_swap_int(&pmap->pm_softhold, 0); 399 wakeup(&pmap->pm_softhold); 400 } 401 402 /* 403 * Move the kernel virtual free pointer to the next 404 * 2MB. This is used to help improve performance 405 * by using a large (2MB) page for much of the kernel 406 * (.text, .data, .bss) 407 */ 408 static 409 vm_offset_t 410 pmap_kmem_choose(vm_offset_t addr) 411 { 412 vm_offset_t newaddr = addr; 413 414 newaddr = roundup2(addr, NBPDR); 415 return newaddr; 416 } 417 418 /* 419 * Returns the pindex of a page table entry (representing a terminal page). 420 * There are NUPTE_TOTAL page table entries possible (a huge number) 421 * 422 * x86-64 has a 48-bit address space, where bit 47 is sign-extended out. 423 * We want to properly translate negative KVAs. 424 */ 425 static __inline 426 vm_pindex_t 427 pmap_pte_pindex(vm_offset_t va) 428 { 429 return ((va >> PAGE_SHIFT) & (NUPTE_TOTAL - 1)); 430 } 431 432 /* 433 * Returns the pindex of a page table. 434 */ 435 static __inline 436 vm_pindex_t 437 pmap_pt_pindex(vm_offset_t va) 438 { 439 return (NUPTE_TOTAL + ((va >> PDRSHIFT) & (NUPT_TOTAL - 1))); 440 } 441 442 /* 443 * Returns the pindex of a page directory. 444 */ 445 static __inline 446 vm_pindex_t 447 pmap_pd_pindex(vm_offset_t va) 448 { 449 return (NUPTE_TOTAL + NUPT_TOTAL + 450 ((va >> PDPSHIFT) & (NUPD_TOTAL - 1))); 451 } 452 453 static __inline 454 vm_pindex_t 455 pmap_pdp_pindex(vm_offset_t va) 456 { 457 return (NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL + 458 ((va >> PML4SHIFT) & (NUPDP_TOTAL - 1))); 459 } 460 461 static __inline 462 vm_pindex_t 463 pmap_pml4_pindex(void) 464 { 465 return (NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL + NUPDP_TOTAL); 466 } 467 468 /* 469 * Return various clipped indexes for a given VA 470 * 471 * Returns the index of a pt in a page directory, representing a page 472 * table. 473 */ 474 static __inline 475 vm_pindex_t 476 pmap_pt_index(vm_offset_t va) 477 { 478 return ((va >> PDRSHIFT) & ((1ul << NPDEPGSHIFT) - 1)); 479 } 480 481 /* 482 * Returns the index of a pd in a page directory page, representing a page 483 * directory. 484 */ 485 static __inline 486 vm_pindex_t 487 pmap_pd_index(vm_offset_t va) 488 { 489 return ((va >> PDPSHIFT) & ((1ul << NPDPEPGSHIFT) - 1)); 490 } 491 492 /* 493 * Returns the index of a pdp in the pml4 table, representing a page 494 * directory page. 495 */ 496 static __inline 497 vm_pindex_t 498 pmap_pdp_index(vm_offset_t va) 499 { 500 return ((va >> PML4SHIFT) & ((1ul << NPML4EPGSHIFT) - 1)); 501 } 502 503 /* 504 * Locate the requested pt_entry 505 */ 506 static __inline 507 pv_entry_t 508 pv_entry_lookup(pmap_t pmap, vm_pindex_t pindex) 509 { 510 pv_entry_t pv; 511 512 if (pindex < pmap_pt_pindex(0)) 513 pv = pmap->pm_pvhint_pte; 514 else if (pindex < pmap_pd_pindex(0)) 515 pv = pmap->pm_pvhint_pt; 516 else 517 pv = NULL; 518 cpu_ccfence(); 519 if (pv == NULL || pv->pv_pmap != pmap) { 520 pv = pv_entry_rb_tree_RB_LOOKUP(&pmap->pm_pvroot, 521 pindex); 522 } else if (pv->pv_pindex != pindex) { 523 pv = pv_entry_rb_tree_RB_LOOKUP_REL(&pmap->pm_pvroot, 524 pindex, pv); 525 } 526 return pv; 527 } 528 529 /* 530 * pmap_pte_quick: 531 * 532 * Super fast pmap_pte routine best used when scanning the pv lists. 533 * This eliminates many course-grained invltlb calls. Note that many of 534 * the pv list scans are across different pmaps and it is very wasteful 535 * to do an entire invltlb when checking a single mapping. 536 */ 537 static __inline pt_entry_t *pmap_pte(pmap_t pmap, vm_offset_t va); 538 539 static 540 pt_entry_t * 541 pmap_pte_quick(pmap_t pmap, vm_offset_t va) 542 { 543 return pmap_pte(pmap, va); 544 } 545 546 /* 547 * The placemarker hash must be broken up into four zones so lock 548 * ordering semantics continue to work (e.g. pte, pt, pd, then pdp). 549 * 550 * Placemarkers are used to 'lock' page table indices that do not have 551 * a pv_entry. This allows the pmap to support managed and unmanaged 552 * pages and shared page tables. 553 */ 554 #define PM_PLACE_BASE (PM_PLACEMARKS >> 2) 555 556 static __inline 557 vm_pindex_t * 558 pmap_placemarker_hash(pmap_t pmap, vm_pindex_t pindex) 559 { 560 int hi; 561 562 if (pindex < pmap_pt_pindex(0)) /* zone 0 - PTE */ 563 hi = 0; 564 else if (pindex < pmap_pd_pindex(0)) /* zone 1 - PT */ 565 hi = PM_PLACE_BASE; 566 else if (pindex < pmap_pdp_pindex(0)) /* zone 2 - PD */ 567 hi = PM_PLACE_BASE << 1; 568 else /* zone 3 - PDP (and PML4E) */ 569 hi = PM_PLACE_BASE | (PM_PLACE_BASE << 1); 570 hi += pindex & (PM_PLACE_BASE - 1); 571 572 return (&pmap->pm_placemarks[hi]); 573 } 574 575 576 /* 577 * Generic procedure to index a pte from a pt, pd, or pdp. 578 * 579 * NOTE: Normally passed pindex as pmap_xx_index(). pmap_xx_pindex() is NOT 580 * a page table page index but is instead of PV lookup index. 581 */ 582 static 583 void * 584 pv_pte_lookup(pv_entry_t pv, vm_pindex_t pindex) 585 { 586 pt_entry_t *pte; 587 588 pte = (pt_entry_t *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(pv->pv_m)); 589 return(&pte[pindex]); 590 } 591 592 /* 593 * Return pointer to PDP slot in the PML4 594 */ 595 static __inline 596 pml4_entry_t * 597 pmap_pdp(pmap_t pmap, vm_offset_t va) 598 { 599 return (&pmap->pm_pml4[pmap_pdp_index(va)]); 600 } 601 602 /* 603 * Return pointer to PD slot in the PDP given a pointer to the PDP 604 */ 605 static __inline 606 pdp_entry_t * 607 pmap_pdp_to_pd(pml4_entry_t pdp_pte, vm_offset_t va) 608 { 609 pdp_entry_t *pd; 610 611 pd = (pdp_entry_t *)PHYS_TO_DMAP(pdp_pte & PG_FRAME); 612 return (&pd[pmap_pd_index(va)]); 613 } 614 615 /* 616 * Return pointer to PD slot in the PDP. 617 */ 618 static __inline 619 pdp_entry_t * 620 pmap_pd(pmap_t pmap, vm_offset_t va) 621 { 622 pml4_entry_t *pdp; 623 624 pdp = pmap_pdp(pmap, va); 625 if ((*pdp & pmap->pmap_bits[PG_V_IDX]) == 0) 626 return NULL; 627 return (pmap_pdp_to_pd(*pdp, va)); 628 } 629 630 /* 631 * Return pointer to PT slot in the PD given a pointer to the PD 632 */ 633 static __inline 634 pd_entry_t * 635 pmap_pd_to_pt(pdp_entry_t pd_pte, vm_offset_t va) 636 { 637 pd_entry_t *pt; 638 639 pt = (pd_entry_t *)PHYS_TO_DMAP(pd_pte & PG_FRAME); 640 return (&pt[pmap_pt_index(va)]); 641 } 642 643 /* 644 * Return pointer to PT slot in the PD 645 * 646 * SIMPLE PMAP NOTE: Simple pmaps (embedded in objects) do not have PDPs, 647 * so we cannot lookup the PD via the PDP. Instead we 648 * must look it up via the pmap. 649 */ 650 static __inline 651 pd_entry_t * 652 pmap_pt(pmap_t pmap, vm_offset_t va) 653 { 654 pdp_entry_t *pd; 655 pv_entry_t pv; 656 vm_pindex_t pd_pindex; 657 vm_paddr_t phys; 658 659 if (pmap->pm_flags & PMAP_FLAG_SIMPLE) { 660 pd_pindex = pmap_pd_pindex(va); 661 spin_lock_shared(&pmap->pm_spin); 662 pv = pv_entry_rb_tree_RB_LOOKUP(&pmap->pm_pvroot, pd_pindex); 663 if (pv == NULL || pv->pv_m == NULL) { 664 spin_unlock_shared(&pmap->pm_spin); 665 return NULL; 666 } 667 phys = VM_PAGE_TO_PHYS(pv->pv_m); 668 spin_unlock_shared(&pmap->pm_spin); 669 return (pmap_pd_to_pt(phys, va)); 670 } else { 671 pd = pmap_pd(pmap, va); 672 if (pd == NULL || (*pd & pmap->pmap_bits[PG_V_IDX]) == 0) 673 return NULL; 674 return (pmap_pd_to_pt(*pd, va)); 675 } 676 } 677 678 /* 679 * Return pointer to PTE slot in the PT given a pointer to the PT 680 */ 681 static __inline 682 pt_entry_t * 683 pmap_pt_to_pte(pd_entry_t pt_pte, vm_offset_t va) 684 { 685 pt_entry_t *pte; 686 687 pte = (pt_entry_t *)PHYS_TO_DMAP(pt_pte & PG_FRAME); 688 return (&pte[pmap_pte_index(va)]); 689 } 690 691 /* 692 * Return pointer to PTE slot in the PT 693 */ 694 static __inline 695 pt_entry_t * 696 pmap_pte(pmap_t pmap, vm_offset_t va) 697 { 698 pd_entry_t *pt; 699 700 pt = pmap_pt(pmap, va); 701 if (pt == NULL || (*pt & pmap->pmap_bits[PG_V_IDX]) == 0) 702 return NULL; 703 if ((*pt & pmap->pmap_bits[PG_PS_IDX]) != 0) 704 return ((pt_entry_t *)pt); 705 return (pmap_pt_to_pte(*pt, va)); 706 } 707 708 /* 709 * Of all the layers (PTE, PT, PD, PDP, PML4) the best one to cache is 710 * the PT layer. This will speed up core pmap operations considerably. 711 * 712 * NOTE: The pmap spinlock does not need to be held but the passed-in pv 713 * must be in a known associated state (typically by being locked when 714 * the pmap spinlock isn't held). We allow the race for that case. 715 * 716 * NOTE: pm_pvhint* is only accessed (read) with the spin-lock held, using 717 * cpu_ccfence() to prevent compiler optimizations from reloading the 718 * field. 719 */ 720 static __inline 721 void 722 pv_cache(pv_entry_t pv, vm_pindex_t pindex) 723 { 724 if (pindex < pmap_pt_pindex(0)) { 725 if (pv->pv_pmap) 726 pv->pv_pmap->pm_pvhint_pte = pv; 727 } else if (pindex < pmap_pd_pindex(0)) { 728 if (pv->pv_pmap) 729 pv->pv_pmap->pm_pvhint_pt = pv; 730 } 731 } 732 733 734 /* 735 * Return address of PT slot in PD (KVM only) 736 * 737 * Cannot be used for user page tables because it might interfere with 738 * the shared page-table-page optimization (pmap_mmu_optimize). 739 */ 740 static __inline 741 pd_entry_t * 742 vtopt(vm_offset_t va) 743 { 744 uint64_t mask = ((1ul << (NPDEPGSHIFT + NPDPEPGSHIFT + 745 NPML4EPGSHIFT)) - 1); 746 747 return (PDmap + ((va >> PDRSHIFT) & mask)); 748 } 749 750 /* 751 * KVM - return address of PTE slot in PT 752 */ 753 static __inline 754 pt_entry_t * 755 vtopte(vm_offset_t va) 756 { 757 uint64_t mask = ((1ul << (NPTEPGSHIFT + NPDEPGSHIFT + 758 NPDPEPGSHIFT + NPML4EPGSHIFT)) - 1); 759 760 return (PTmap + ((va >> PAGE_SHIFT) & mask)); 761 } 762 763 /* 764 * Returns the physical address translation from va for a user address. 765 * (vm_paddr_t)-1 is returned on failure. 766 */ 767 vm_paddr_t 768 uservtophys(vm_offset_t va) 769 { 770 uint64_t mask = ((1ul << (NPTEPGSHIFT + NPDEPGSHIFT + 771 NPDPEPGSHIFT + NPML4EPGSHIFT)) - 1); 772 vm_paddr_t pa; 773 pt_entry_t pte; 774 pmap_t pmap; 775 776 pmap = vmspace_pmap(mycpu->gd_curthread->td_lwp->lwp_vmspace); 777 pa = (vm_paddr_t)-1; 778 if (va < VM_MAX_USER_ADDRESS) { 779 pte = kreadmem64(PTmap + ((va >> PAGE_SHIFT) & mask)); 780 if (pte & pmap->pmap_bits[PG_V_IDX]) 781 pa = (pte & PG_FRAME) | (va & PAGE_MASK); 782 } 783 return pa; 784 } 785 786 static uint64_t 787 allocpages(vm_paddr_t *firstaddr, long n) 788 { 789 uint64_t ret; 790 791 ret = *firstaddr; 792 bzero((void *)ret, n * PAGE_SIZE); 793 *firstaddr += n * PAGE_SIZE; 794 return (ret); 795 } 796 797 static 798 void 799 create_pagetables(vm_paddr_t *firstaddr) 800 { 801 long i; /* must be 64 bits */ 802 long nkpt_base; 803 long nkpt_phys; 804 long nkpd_phys; 805 int j; 806 807 /* 808 * We are running (mostly) V=P at this point 809 * 810 * Calculate how many 1GB PD entries in our PDP pages are needed 811 * for the DMAP. This is only allocated if the system does not 812 * support 1GB pages. Otherwise ndmpdp is simply a count of 813 * the number of 1G terminal entries in our PDP pages are needed. 814 * 815 * NOTE: Maxmem is in pages 816 */ 817 ndmpdp = (ptoa(Maxmem) + NBPDP - 1) >> PDPSHIFT; 818 if (ndmpdp < 4) /* Minimum 4GB of dirmap */ 819 ndmpdp = 4; 820 KKASSERT(ndmpdp <= NDMPML4E * NPML4EPG); 821 822 /* 823 * Starting at KERNBASE - map all 2G worth of page table pages. 824 * KERNBASE is offset -2G from the end of kvm. This will accomodate 825 * all KVM allocations above KERNBASE, including the SYSMAPs below. 826 * 827 * We do this by allocating 2*512 PT pages. Each PT page can map 828 * 2MB, for 2GB total. 829 */ 830 nkpt_base = (NPDPEPG - KPDPI) * NPTEPG; /* typically 2 x 512 */ 831 832 /* 833 * Starting at the beginning of kvm (VM_MIN_KERNEL_ADDRESS), 834 * Calculate how many page table pages we need to preallocate 835 * for early vm_map allocations. 836 * 837 * A few extra won't hurt, they will get used up in the running 838 * system. 839 * 840 * vm_page array 841 * initial pventry's 842 */ 843 nkpt_phys = (Maxmem * sizeof(struct vm_page) + NBPDR - 1) / NBPDR; 844 nkpt_phys += (Maxmem * sizeof(struct pv_entry) + NBPDR - 1) / NBPDR; 845 nkpt_phys += 128; /* a few extra */ 846 847 /* 848 * The highest value nkpd_phys can be set to is 849 * NKPDPE - (NPDPEPG - KPDPI) (i.e. NKPDPE - 2). 850 * 851 * Doing so would cause all PD pages to be pre-populated for 852 * a maximal KVM space (approximately 16*512 pages, or 32MB. 853 * We can save memory by not doing this. 854 */ 855 nkpd_phys = (nkpt_phys + NPDPEPG - 1) / NPDPEPG; 856 857 /* 858 * Allocate pages 859 * 860 * Normally NKPML4E=1-16 (1-16 kernel PDP page) 861 * Normally NKPDPE= NKPML4E*512-1 (511 min kernel PD pages) 862 * 863 * Only allocate enough PD pages 864 * NOTE: We allocate all kernel PD pages up-front, typically 865 * ~511G of KVM, requiring 511 PD pages. 866 */ 867 KPTbase = allocpages(firstaddr, nkpt_base); /* KERNBASE to end */ 868 KPTphys = allocpages(firstaddr, nkpt_phys); /* KVA start */ 869 KPML4phys = allocpages(firstaddr, 1); /* recursive PML4 map */ 870 KPDPphys = allocpages(firstaddr, NKPML4E); /* kernel PDP pages */ 871 KPDphys = allocpages(firstaddr, nkpd_phys); /* kernel PD pages */ 872 873 /* 874 * Alloc PD pages for the area starting at KERNBASE. 875 */ 876 KPDbase = allocpages(firstaddr, NPDPEPG - KPDPI); 877 878 /* 879 * Stuff for our DMAP 880 */ 881 DMPDPphys = allocpages(firstaddr, NDMPML4E); 882 if ((amd_feature & AMDID_PAGE1GB) == 0) 883 DMPDphys = allocpages(firstaddr, ndmpdp); 884 dmaplimit = (vm_paddr_t)ndmpdp << PDPSHIFT; 885 886 /* 887 * Fill in the underlying page table pages for the area around 888 * KERNBASE. This remaps low physical memory to KERNBASE. 889 * 890 * Read-only from zero to physfree 891 * XXX not fully used, underneath 2M pages 892 */ 893 for (i = 0; (i << PAGE_SHIFT) < *firstaddr; i++) { 894 ((pt_entry_t *)KPTbase)[i] = i << PAGE_SHIFT; 895 ((pt_entry_t *)KPTbase)[i] |= 896 pmap_bits_default[PG_RW_IDX] | 897 pmap_bits_default[PG_V_IDX] | 898 pmap_bits_default[PG_G_IDX]; 899 } 900 901 /* 902 * Now map the initial kernel page tables. One block of page 903 * tables is placed at the beginning of kernel virtual memory, 904 * and another block is placed at KERNBASE to map the kernel binary, 905 * data, bss, and initial pre-allocations. 906 */ 907 for (i = 0; i < nkpt_base; i++) { 908 ((pd_entry_t *)KPDbase)[i] = KPTbase + (i << PAGE_SHIFT); 909 ((pd_entry_t *)KPDbase)[i] |= 910 pmap_bits_default[PG_RW_IDX] | 911 pmap_bits_default[PG_V_IDX]; 912 } 913 for (i = 0; i < nkpt_phys; i++) { 914 ((pd_entry_t *)KPDphys)[i] = KPTphys + (i << PAGE_SHIFT); 915 ((pd_entry_t *)KPDphys)[i] |= 916 pmap_bits_default[PG_RW_IDX] | 917 pmap_bits_default[PG_V_IDX]; 918 } 919 920 /* 921 * Map from zero to end of allocations using 2M pages as an 922 * optimization. This will bypass some of the KPTBase pages 923 * above in the KERNBASE area. 924 */ 925 for (i = 0; (i << PDRSHIFT) < *firstaddr; i++) { 926 ((pd_entry_t *)KPDbase)[i] = i << PDRSHIFT; 927 ((pd_entry_t *)KPDbase)[i] |= 928 pmap_bits_default[PG_RW_IDX] | 929 pmap_bits_default[PG_V_IDX] | 930 pmap_bits_default[PG_PS_IDX] | 931 pmap_bits_default[PG_G_IDX]; 932 } 933 934 /* 935 * Load PD addresses into the PDP pages for primary KVA space to 936 * cover existing page tables. PD's for KERNBASE are handled in 937 * the next loop. 938 * 939 * expected to pre-populate all of its PDs. See NKPDPE in vmparam.h. 940 */ 941 for (i = 0; i < nkpd_phys; i++) { 942 ((pdp_entry_t *)KPDPphys)[NKPML4E * NPDPEPG - NKPDPE + i] = 943 KPDphys + (i << PAGE_SHIFT); 944 ((pdp_entry_t *)KPDPphys)[NKPML4E * NPDPEPG - NKPDPE + i] |= 945 pmap_bits_default[PG_RW_IDX] | 946 pmap_bits_default[PG_V_IDX] | 947 pmap_bits_default[PG_U_IDX]; 948 } 949 950 /* 951 * Load PDs for KERNBASE to the end 952 */ 953 i = (NKPML4E - 1) * NPDPEPG + KPDPI; 954 for (j = 0; j < NPDPEPG - KPDPI; ++j) { 955 ((pdp_entry_t *)KPDPphys)[i + j] = 956 KPDbase + (j << PAGE_SHIFT); 957 ((pdp_entry_t *)KPDPphys)[i + j] |= 958 pmap_bits_default[PG_RW_IDX] | 959 pmap_bits_default[PG_V_IDX] | 960 pmap_bits_default[PG_U_IDX]; 961 } 962 963 /* 964 * Now set up the direct map space using either 2MB or 1GB pages 965 * Preset PG_M and PG_A because demotion expects it. 966 * 967 * When filling in entries in the PD pages make sure any excess 968 * entries are set to zero as we allocated enough PD pages 969 */ 970 if ((amd_feature & AMDID_PAGE1GB) == 0) { 971 for (i = 0; i < NPDEPG * ndmpdp; i++) { 972 ((pd_entry_t *)DMPDphys)[i] = i << PDRSHIFT; 973 ((pd_entry_t *)DMPDphys)[i] |= 974 pmap_bits_default[PG_RW_IDX] | 975 pmap_bits_default[PG_V_IDX] | 976 pmap_bits_default[PG_PS_IDX] | 977 pmap_bits_default[PG_G_IDX] | 978 pmap_bits_default[PG_M_IDX] | 979 pmap_bits_default[PG_A_IDX]; 980 } 981 982 /* 983 * And the direct map space's PDP 984 */ 985 for (i = 0; i < ndmpdp; i++) { 986 ((pdp_entry_t *)DMPDPphys)[i] = DMPDphys + 987 (i << PAGE_SHIFT); 988 ((pdp_entry_t *)DMPDPphys)[i] |= 989 pmap_bits_default[PG_RW_IDX] | 990 pmap_bits_default[PG_V_IDX] | 991 pmap_bits_default[PG_U_IDX]; 992 } 993 } else { 994 for (i = 0; i < ndmpdp; i++) { 995 ((pdp_entry_t *)DMPDPphys)[i] = 996 (vm_paddr_t)i << PDPSHIFT; 997 ((pdp_entry_t *)DMPDPphys)[i] |= 998 pmap_bits_default[PG_RW_IDX] | 999 pmap_bits_default[PG_V_IDX] | 1000 pmap_bits_default[PG_PS_IDX] | 1001 pmap_bits_default[PG_G_IDX] | 1002 pmap_bits_default[PG_M_IDX] | 1003 pmap_bits_default[PG_A_IDX]; 1004 } 1005 } 1006 1007 /* And recursively map PML4 to itself in order to get PTmap */ 1008 ((pdp_entry_t *)KPML4phys)[PML4PML4I] = KPML4phys; 1009 ((pdp_entry_t *)KPML4phys)[PML4PML4I] |= 1010 pmap_bits_default[PG_RW_IDX] | 1011 pmap_bits_default[PG_V_IDX] | 1012 pmap_bits_default[PG_U_IDX]; 1013 1014 /* 1015 * Connect the Direct Map slots up to the PML4 1016 */ 1017 for (j = 0; j < NDMPML4E; ++j) { 1018 ((pdp_entry_t *)KPML4phys)[DMPML4I + j] = 1019 (DMPDPphys + ((vm_paddr_t)j << PAGE_SHIFT)) | 1020 pmap_bits_default[PG_RW_IDX] | 1021 pmap_bits_default[PG_V_IDX] | 1022 pmap_bits_default[PG_U_IDX]; 1023 } 1024 1025 /* 1026 * Connect the KVA slot up to the PML4 1027 */ 1028 for (j = 0; j < NKPML4E; ++j) { 1029 ((pdp_entry_t *)KPML4phys)[KPML4I + j] = 1030 KPDPphys + ((vm_paddr_t)j << PAGE_SHIFT); 1031 ((pdp_entry_t *)KPML4phys)[KPML4I + j] |= 1032 pmap_bits_default[PG_RW_IDX] | 1033 pmap_bits_default[PG_V_IDX] | 1034 pmap_bits_default[PG_U_IDX]; 1035 } 1036 cpu_mfence(); 1037 cpu_invltlb(); 1038 } 1039 1040 /* 1041 * Bootstrap the system enough to run with virtual memory. 1042 * 1043 * On the i386 this is called after mapping has already been enabled 1044 * and just syncs the pmap module with what has already been done. 1045 * [We can't call it easily with mapping off since the kernel is not 1046 * mapped with PA == VA, hence we would have to relocate every address 1047 * from the linked base (virtual) address "KERNBASE" to the actual 1048 * (physical) address starting relative to 0] 1049 */ 1050 void 1051 pmap_bootstrap(vm_paddr_t *firstaddr) 1052 { 1053 vm_offset_t va; 1054 pt_entry_t *pte; 1055 int i; 1056 1057 KvaStart = VM_MIN_KERNEL_ADDRESS; 1058 KvaEnd = VM_MAX_KERNEL_ADDRESS; 1059 KvaSize = KvaEnd - KvaStart; 1060 1061 avail_start = *firstaddr; 1062 1063 /* 1064 * Create an initial set of page tables to run the kernel in. 1065 */ 1066 create_pagetables(firstaddr); 1067 1068 virtual2_start = KvaStart; 1069 virtual2_end = PTOV_OFFSET; 1070 1071 virtual_start = (vm_offset_t) PTOV_OFFSET + *firstaddr; 1072 virtual_start = pmap_kmem_choose(virtual_start); 1073 1074 virtual_end = VM_MAX_KERNEL_ADDRESS; 1075 1076 /* XXX do %cr0 as well */ 1077 load_cr4(rcr4() | CR4_PGE | CR4_PSE); 1078 load_cr3(KPML4phys); 1079 1080 /* 1081 * Initialize protection array. 1082 */ 1083 i386_protection_init(); 1084 1085 /* 1086 * The kernel's pmap is statically allocated so we don't have to use 1087 * pmap_create, which is unlikely to work correctly at this part of 1088 * the boot sequence (XXX and which no longer exists). 1089 */ 1090 kernel_pmap.pm_pml4 = (pdp_entry_t *) (PTOV_OFFSET + KPML4phys); 1091 kernel_pmap.pm_count = 1; 1092 CPUMASK_ASSALLONES(kernel_pmap.pm_active); 1093 RB_INIT(&kernel_pmap.pm_pvroot); 1094 spin_init(&kernel_pmap.pm_spin, "pmapbootstrap"); 1095 for (i = 0; i < PM_PLACEMARKS; ++i) 1096 kernel_pmap.pm_placemarks[i] = PM_NOPLACEMARK; 1097 1098 /* 1099 * Reserve some special page table entries/VA space for temporary 1100 * mapping of pages. 1101 */ 1102 #define SYSMAP(c, p, v, n) \ 1103 v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n); 1104 1105 va = virtual_start; 1106 pte = vtopte(va); 1107 1108 /* 1109 * CMAP1/CMAP2 are used for zeroing and copying pages. 1110 */ 1111 SYSMAP(caddr_t, CMAP1, CADDR1, 1) 1112 1113 /* 1114 * Crashdump maps. 1115 */ 1116 SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS); 1117 1118 /* 1119 * ptvmmap is used for reading arbitrary physical pages via 1120 * /dev/mem. 1121 */ 1122 SYSMAP(caddr_t, ptmmap, ptvmmap, 1) 1123 1124 /* 1125 * msgbufp is used to map the system message buffer. 1126 * XXX msgbufmap is not used. 1127 */ 1128 SYSMAP(struct msgbuf *, msgbufmap, msgbufp, 1129 atop(round_page(MSGBUF_SIZE))) 1130 1131 virtual_start = va; 1132 virtual_start = pmap_kmem_choose(virtual_start); 1133 1134 *CMAP1 = 0; 1135 1136 /* 1137 * PG_G is terribly broken on SMP because we IPI invltlb's in some 1138 * cases rather then invl1pg. Actually, I don't even know why it 1139 * works under UP because self-referential page table mappings 1140 */ 1141 // pgeflag = 0; 1142 1143 cpu_invltlb(); 1144 1145 /* Initialize the PAT MSR */ 1146 pmap_init_pat(); 1147 pmap_pinit_defaults(&kernel_pmap); 1148 1149 TUNABLE_INT_FETCH("machdep.pmap_fast_kernel_cpusync", 1150 &pmap_fast_kernel_cpusync); 1151 1152 } 1153 1154 /* 1155 * Setup the PAT MSR. 1156 */ 1157 void 1158 pmap_init_pat(void) 1159 { 1160 uint64_t pat_msr; 1161 u_long cr0, cr4; 1162 1163 /* 1164 * Default values mapping PATi,PCD,PWT bits at system reset. 1165 * The default values effectively ignore the PATi bit by 1166 * repeating the encodings for 0-3 in 4-7, and map the PCD 1167 * and PWT bit combinations to the expected PAT types. 1168 */ 1169 pat_msr = PAT_VALUE(0, PAT_WRITE_BACK) | /* 000 */ 1170 PAT_VALUE(1, PAT_WRITE_THROUGH) | /* 001 */ 1171 PAT_VALUE(2, PAT_UNCACHED) | /* 010 */ 1172 PAT_VALUE(3, PAT_UNCACHEABLE) | /* 011 */ 1173 PAT_VALUE(4, PAT_WRITE_BACK) | /* 100 */ 1174 PAT_VALUE(5, PAT_WRITE_THROUGH) | /* 101 */ 1175 PAT_VALUE(6, PAT_UNCACHED) | /* 110 */ 1176 PAT_VALUE(7, PAT_UNCACHEABLE); /* 111 */ 1177 pat_pte_index[PAT_WRITE_BACK] = 0; 1178 pat_pte_index[PAT_WRITE_THROUGH]= 0 | X86_PG_NC_PWT; 1179 pat_pte_index[PAT_UNCACHED] = X86_PG_NC_PCD; 1180 pat_pte_index[PAT_UNCACHEABLE] = X86_PG_NC_PCD | X86_PG_NC_PWT; 1181 pat_pte_index[PAT_WRITE_PROTECTED] = pat_pte_index[PAT_UNCACHEABLE]; 1182 pat_pte_index[PAT_WRITE_COMBINING] = pat_pte_index[PAT_UNCACHEABLE]; 1183 1184 if (cpu_feature & CPUID_PAT) { 1185 /* 1186 * If we support the PAT then set-up entries for 1187 * WRITE_PROTECTED and WRITE_COMBINING using bit patterns 1188 * 5 and 6. 1189 */ 1190 pat_msr = (pat_msr & ~PAT_MASK(5)) | 1191 PAT_VALUE(5, PAT_WRITE_PROTECTED); 1192 pat_msr = (pat_msr & ~PAT_MASK(6)) | 1193 PAT_VALUE(6, PAT_WRITE_COMBINING); 1194 pat_pte_index[PAT_WRITE_PROTECTED] = X86_PG_PTE_PAT | X86_PG_NC_PWT; 1195 pat_pte_index[PAT_WRITE_COMBINING] = X86_PG_PTE_PAT | X86_PG_NC_PCD; 1196 1197 /* 1198 * Then enable the PAT 1199 */ 1200 1201 /* Disable PGE. */ 1202 cr4 = rcr4(); 1203 load_cr4(cr4 & ~CR4_PGE); 1204 1205 /* Disable caches (CD = 1, NW = 0). */ 1206 cr0 = rcr0(); 1207 load_cr0((cr0 & ~CR0_NW) | CR0_CD); 1208 1209 /* Flushes caches and TLBs. */ 1210 wbinvd(); 1211 cpu_invltlb(); 1212 1213 /* Update PAT and index table. */ 1214 wrmsr(MSR_PAT, pat_msr); 1215 1216 /* Flush caches and TLBs again. */ 1217 wbinvd(); 1218 cpu_invltlb(); 1219 1220 /* Restore caches and PGE. */ 1221 load_cr0(cr0); 1222 load_cr4(cr4); 1223 PatMsr = pat_msr; 1224 } 1225 } 1226 1227 /* 1228 * Set 4mb pdir for mp startup 1229 */ 1230 void 1231 pmap_set_opt(void) 1232 { 1233 if (cpu_feature & CPUID_PSE) { 1234 load_cr4(rcr4() | CR4_PSE); 1235 if (mycpu->gd_cpuid == 0) /* only on BSP */ 1236 cpu_invltlb(); 1237 } 1238 } 1239 1240 /* 1241 * Initialize the pmap module. 1242 * Called by vm_init, to initialize any structures that the pmap 1243 * system needs to map virtual memory. 1244 * pmap_init has been enhanced to support in a fairly consistant 1245 * way, discontiguous physical memory. 1246 */ 1247 void 1248 pmap_init(void) 1249 { 1250 vm_pindex_t initial_pvs; 1251 vm_pindex_t i; 1252 1253 /* 1254 * Allocate memory for random pmap data structures. Includes the 1255 * pv_head_table. 1256 */ 1257 1258 for (i = 0; i < vm_page_array_size; i++) { 1259 vm_page_t m; 1260 1261 m = &vm_page_array[i]; 1262 TAILQ_INIT(&m->md.pv_list); 1263 } 1264 1265 /* 1266 * init the pv free list 1267 */ 1268 initial_pvs = vm_page_array_size; 1269 if (initial_pvs < MINPV) 1270 initial_pvs = MINPV; 1271 pvzone = &pvzone_store; 1272 pvinit = (void *)kmem_alloc(&kernel_map, 1273 initial_pvs * sizeof (struct pv_entry), 1274 VM_SUBSYS_PVENTRY); 1275 zbootinit(pvzone, "PV ENTRY", sizeof (struct pv_entry), 1276 pvinit, initial_pvs); 1277 1278 /* 1279 * Now it is safe to enable pv_table recording. 1280 */ 1281 pmap_initialized = TRUE; 1282 } 1283 1284 /* 1285 * Initialize the address space (zone) for the pv_entries. Set a 1286 * high water mark so that the system can recover from excessive 1287 * numbers of pv entries. 1288 */ 1289 void 1290 pmap_init2(void) 1291 { 1292 vm_pindex_t shpgperproc = PMAP_SHPGPERPROC; 1293 vm_pindex_t entry_max; 1294 1295 TUNABLE_LONG_FETCH("vm.pmap.shpgperproc", &shpgperproc); 1296 pv_entry_max = shpgperproc * maxproc + vm_page_array_size; 1297 TUNABLE_LONG_FETCH("vm.pmap.pv_entries", &pv_entry_max); 1298 pv_entry_high_water = 9 * (pv_entry_max / 10); 1299 1300 /* 1301 * Subtract out pages already installed in the zone (hack) 1302 */ 1303 entry_max = pv_entry_max - vm_page_array_size; 1304 if (entry_max <= 0) 1305 entry_max = 1; 1306 1307 zinitna(pvzone, NULL, 0, entry_max, ZONE_INTERRUPT); 1308 1309 /* 1310 * Enable dynamic deletion of empty higher-level page table pages 1311 * by default only if system memory is < 8GB (use 7GB for slop). 1312 * This can save a little memory, but imposes significant 1313 * performance overhead for things like bulk builds, and for programs 1314 * which do a lot of memory mapping and memory unmapping. 1315 */ 1316 if (pmap_dynamic_delete < 0) { 1317 if (vmstats.v_page_count < 7LL * 1024 * 1024 * 1024 / PAGE_SIZE) 1318 pmap_dynamic_delete = 1; 1319 else 1320 pmap_dynamic_delete = 0; 1321 } 1322 } 1323 1324 /* 1325 * Typically used to initialize a fictitious page by vm/device_pager.c 1326 */ 1327 void 1328 pmap_page_init(struct vm_page *m) 1329 { 1330 vm_page_init(m); 1331 TAILQ_INIT(&m->md.pv_list); 1332 } 1333 1334 /*************************************************** 1335 * Low level helper routines..... 1336 ***************************************************/ 1337 1338 /* 1339 * this routine defines the region(s) of memory that should 1340 * not be tested for the modified bit. 1341 */ 1342 static __inline 1343 int 1344 pmap_track_modified(vm_pindex_t pindex) 1345 { 1346 vm_offset_t va = (vm_offset_t)pindex << PAGE_SHIFT; 1347 if ((va < clean_sva) || (va >= clean_eva)) 1348 return 1; 1349 else 1350 return 0; 1351 } 1352 1353 /* 1354 * Extract the physical page address associated with the map/VA pair. 1355 * The page must be wired for this to work reliably. 1356 */ 1357 vm_paddr_t 1358 pmap_extract(pmap_t pmap, vm_offset_t va, void **handlep) 1359 { 1360 vm_paddr_t rtval; 1361 pv_entry_t pt_pv; 1362 pt_entry_t *ptep; 1363 1364 rtval = 0; 1365 if (va >= VM_MAX_USER_ADDRESS) { 1366 /* 1367 * Kernel page directories might be direct-mapped and 1368 * there is typically no PV tracking of pte's 1369 */ 1370 pd_entry_t *pt; 1371 1372 pt = pmap_pt(pmap, va); 1373 if (pt && (*pt & pmap->pmap_bits[PG_V_IDX])) { 1374 if (*pt & pmap->pmap_bits[PG_PS_IDX]) { 1375 rtval = *pt & PG_PS_FRAME; 1376 rtval |= va & PDRMASK; 1377 } else { 1378 ptep = pmap_pt_to_pte(*pt, va); 1379 if (*pt & pmap->pmap_bits[PG_V_IDX]) { 1380 rtval = *ptep & PG_FRAME; 1381 rtval |= va & PAGE_MASK; 1382 } 1383 } 1384 } 1385 if (handlep) 1386 *handlep = NULL; 1387 } else { 1388 /* 1389 * User pages currently do not direct-map the page directory 1390 * and some pages might not used managed PVs. But all PT's 1391 * will have a PV. 1392 */ 1393 pt_pv = pv_get(pmap, pmap_pt_pindex(va), NULL); 1394 if (pt_pv) { 1395 ptep = pv_pte_lookup(pt_pv, pmap_pte_index(va)); 1396 if (*ptep & pmap->pmap_bits[PG_V_IDX]) { 1397 rtval = *ptep & PG_FRAME; 1398 rtval |= va & PAGE_MASK; 1399 } 1400 if (handlep) 1401 *handlep = pt_pv; /* locked until done */ 1402 else 1403 pv_put (pt_pv); 1404 } else if (handlep) { 1405 *handlep = NULL; 1406 } 1407 } 1408 return rtval; 1409 } 1410 1411 void 1412 pmap_extract_done(void *handle) 1413 { 1414 if (handle) 1415 pv_put((pv_entry_t)handle); 1416 } 1417 1418 /* 1419 * Similar to extract but checks protections, SMP-friendly short-cut for 1420 * vm_fault_page[_quick](). Can return NULL to cause the caller to 1421 * fall-through to the real fault code. Does not work with HVM page 1422 * tables. 1423 * 1424 * if busyp is NULL the returned page, if not NULL, is held (and not busied). 1425 * 1426 * If busyp is not NULL and this function sets *busyp non-zero, the returned 1427 * page is busied (and not held). 1428 * 1429 * If busyp is not NULL and this function sets *busyp to zero, the returned 1430 * page is held (and not busied). 1431 * 1432 * If VM_PROT_WRITE is set in prot, and the pte is already writable, the 1433 * returned page will be dirtied. If the pte is not already writable NULL 1434 * is returned. In otherwords, if the bit is set and a vm_page_t is returned, 1435 * any COW will already have happened and that page can be written by the 1436 * caller. 1437 * 1438 * WARNING! THE RETURNED PAGE IS ONLY HELD AND NOT SUITABLE FOR READING 1439 * OR WRITING AS-IS. 1440 */ 1441 vm_page_t 1442 pmap_fault_page_quick(pmap_t pmap, vm_offset_t va, vm_prot_t prot, int *busyp) 1443 { 1444 if (pmap && 1445 va < VM_MAX_USER_ADDRESS && 1446 (pmap->pm_flags & PMAP_HVM) == 0) { 1447 pv_entry_t pt_pv; 1448 pv_entry_t pte_pv; 1449 pt_entry_t *ptep; 1450 pt_entry_t req; 1451 vm_page_t m; 1452 int error; 1453 1454 req = pmap->pmap_bits[PG_V_IDX] | 1455 pmap->pmap_bits[PG_U_IDX]; 1456 if (prot & VM_PROT_WRITE) 1457 req |= pmap->pmap_bits[PG_RW_IDX]; 1458 1459 pt_pv = pv_get(pmap, pmap_pt_pindex(va), NULL); 1460 if (pt_pv == NULL) 1461 return (NULL); 1462 ptep = pv_pte_lookup(pt_pv, pmap_pte_index(va)); 1463 if ((*ptep & req) != req) { 1464 pv_put(pt_pv); 1465 return (NULL); 1466 } 1467 pte_pv = pv_get_try(pmap, pmap_pte_pindex(va), NULL, &error); 1468 if (pte_pv && error == 0) { 1469 m = pte_pv->pv_m; 1470 if (prot & VM_PROT_WRITE) { 1471 /* interlocked by presence of pv_entry */ 1472 vm_page_dirty(m); 1473 } 1474 if (busyp) { 1475 if (prot & VM_PROT_WRITE) { 1476 if (vm_page_busy_try(m, TRUE)) 1477 m = NULL; 1478 *busyp = 1; 1479 } else { 1480 vm_page_hold(m); 1481 *busyp = 0; 1482 } 1483 } else { 1484 vm_page_hold(m); 1485 } 1486 pv_put(pte_pv); 1487 } else if (pte_pv) { 1488 pv_drop(pte_pv); 1489 m = NULL; 1490 } else { 1491 /* error, since we didn't request a placemarker */ 1492 m = NULL; 1493 } 1494 pv_put(pt_pv); 1495 return(m); 1496 } else { 1497 return(NULL); 1498 } 1499 } 1500 1501 /* 1502 * Extract the physical page address associated kernel virtual address. 1503 */ 1504 vm_paddr_t 1505 pmap_kextract(vm_offset_t va) 1506 { 1507 pd_entry_t pt; /* pt entry in pd */ 1508 vm_paddr_t pa; 1509 1510 if (va >= DMAP_MIN_ADDRESS && va < DMAP_MAX_ADDRESS) { 1511 pa = DMAP_TO_PHYS(va); 1512 } else { 1513 pt = *vtopt(va); 1514 if (pt & kernel_pmap.pmap_bits[PG_PS_IDX]) { 1515 pa = (pt & PG_PS_FRAME) | (va & PDRMASK); 1516 } else { 1517 /* 1518 * Beware of a concurrent promotion that changes the 1519 * PDE at this point! For example, vtopte() must not 1520 * be used to access the PTE because it would use the 1521 * new PDE. It is, however, safe to use the old PDE 1522 * because the page table page is preserved by the 1523 * promotion. 1524 */ 1525 pa = *pmap_pt_to_pte(pt, va); 1526 pa = (pa & PG_FRAME) | (va & PAGE_MASK); 1527 } 1528 } 1529 return pa; 1530 } 1531 1532 /*************************************************** 1533 * Low level mapping routines..... 1534 ***************************************************/ 1535 1536 /* 1537 * Routine: pmap_kenter 1538 * Function: 1539 * Add a wired page to the KVA 1540 * NOTE! note that in order for the mapping to take effect -- you 1541 * should do an invltlb after doing the pmap_kenter(). 1542 */ 1543 void 1544 pmap_kenter(vm_offset_t va, vm_paddr_t pa) 1545 { 1546 pt_entry_t *ptep; 1547 pt_entry_t npte; 1548 1549 npte = pa | 1550 kernel_pmap.pmap_bits[PG_RW_IDX] | 1551 kernel_pmap.pmap_bits[PG_V_IDX]; 1552 // pgeflag; 1553 ptep = vtopte(va); 1554 #if 1 1555 pmap_inval_smp(&kernel_pmap, va, 1, ptep, npte); 1556 #else 1557 /* FUTURE */ 1558 if (*ptep) 1559 pmap_inval_smp(&kernel_pmap, va, ptep, npte); 1560 else 1561 *ptep = npte; 1562 #endif 1563 } 1564 1565 /* 1566 * Similar to pmap_kenter(), except we only invalidate the mapping on the 1567 * current CPU. Returns 0 if the previous pte was 0, 1 if it wasn't 1568 * (caller can conditionalize calling smp_invltlb()). 1569 */ 1570 int 1571 pmap_kenter_quick(vm_offset_t va, vm_paddr_t pa) 1572 { 1573 pt_entry_t *ptep; 1574 pt_entry_t npte; 1575 int res; 1576 1577 npte = pa | kernel_pmap.pmap_bits[PG_RW_IDX] | 1578 kernel_pmap.pmap_bits[PG_V_IDX]; 1579 // npte |= pgeflag; 1580 ptep = vtopte(va); 1581 #if 1 1582 res = 1; 1583 #else 1584 /* FUTURE */ 1585 res = (*ptep != 0); 1586 #endif 1587 atomic_swap_long(ptep, npte); 1588 cpu_invlpg((void *)va); 1589 1590 return res; 1591 } 1592 1593 /* 1594 * Enter addresses into the kernel pmap but don't bother 1595 * doing any tlb invalidations. Caller will do a rollup 1596 * invalidation via pmap_rollup_inval(). 1597 */ 1598 int 1599 pmap_kenter_noinval(vm_offset_t va, vm_paddr_t pa) 1600 { 1601 pt_entry_t *ptep; 1602 pt_entry_t npte; 1603 int res; 1604 1605 npte = pa | 1606 kernel_pmap.pmap_bits[PG_RW_IDX] | 1607 kernel_pmap.pmap_bits[PG_V_IDX]; 1608 // pgeflag; 1609 ptep = vtopte(va); 1610 #if 1 1611 res = 1; 1612 #else 1613 /* FUTURE */ 1614 res = (*ptep != 0); 1615 #endif 1616 atomic_swap_long(ptep, npte); 1617 cpu_invlpg((void *)va); 1618 1619 return res; 1620 } 1621 1622 /* 1623 * remove a page from the kernel pagetables 1624 */ 1625 void 1626 pmap_kremove(vm_offset_t va) 1627 { 1628 pt_entry_t *ptep; 1629 1630 ptep = vtopte(va); 1631 pmap_inval_smp(&kernel_pmap, va, 1, ptep, 0); 1632 } 1633 1634 void 1635 pmap_kremove_quick(vm_offset_t va) 1636 { 1637 pt_entry_t *ptep; 1638 1639 ptep = vtopte(va); 1640 (void)pte_load_clear(ptep); 1641 cpu_invlpg((void *)va); 1642 } 1643 1644 /* 1645 * Remove addresses from the kernel pmap but don't bother 1646 * doing any tlb invalidations. Caller will do a rollup 1647 * invalidation via pmap_rollup_inval(). 1648 */ 1649 void 1650 pmap_kremove_noinval(vm_offset_t va) 1651 { 1652 pt_entry_t *ptep; 1653 1654 ptep = vtopte(va); 1655 (void)pte_load_clear(ptep); 1656 } 1657 1658 /* 1659 * XXX these need to be recoded. They are not used in any critical path. 1660 */ 1661 void 1662 pmap_kmodify_rw(vm_offset_t va) 1663 { 1664 atomic_set_long(vtopte(va), kernel_pmap.pmap_bits[PG_RW_IDX]); 1665 cpu_invlpg((void *)va); 1666 } 1667 1668 /* NOT USED 1669 void 1670 pmap_kmodify_nc(vm_offset_t va) 1671 { 1672 atomic_set_long(vtopte(va), PG_N); 1673 cpu_invlpg((void *)va); 1674 } 1675 */ 1676 1677 /* 1678 * Used to map a range of physical addresses into kernel virtual 1679 * address space during the low level boot, typically to map the 1680 * dump bitmap, message buffer, and vm_page_array. 1681 * 1682 * These mappings are typically made at some pointer after the end of the 1683 * kernel text+data. 1684 * 1685 * We could return PHYS_TO_DMAP(start) here and not allocate any 1686 * via (*virtp), but then kmem from userland and kernel dumps won't 1687 * have access to the related pointers. 1688 */ 1689 vm_offset_t 1690 pmap_map(vm_offset_t *virtp, vm_paddr_t start, vm_paddr_t end, int prot) 1691 { 1692 vm_offset_t va; 1693 vm_offset_t va_start; 1694 1695 /*return PHYS_TO_DMAP(start);*/ 1696 1697 va_start = *virtp; 1698 va = va_start; 1699 1700 while (start < end) { 1701 pmap_kenter_quick(va, start); 1702 va += PAGE_SIZE; 1703 start += PAGE_SIZE; 1704 } 1705 *virtp = va; 1706 return va_start; 1707 } 1708 1709 #define PMAP_CLFLUSH_THRESHOLD (2 * 1024 * 1024) 1710 1711 /* 1712 * Remove the specified set of pages from the data and instruction caches. 1713 * 1714 * In contrast to pmap_invalidate_cache_range(), this function does not 1715 * rely on the CPU's self-snoop feature, because it is intended for use 1716 * when moving pages into a different cache domain. 1717 */ 1718 void 1719 pmap_invalidate_cache_pages(vm_page_t *pages, int count) 1720 { 1721 vm_offset_t daddr, eva; 1722 int i; 1723 1724 if (count >= PMAP_CLFLUSH_THRESHOLD / PAGE_SIZE || 1725 (cpu_feature & CPUID_CLFSH) == 0) 1726 wbinvd(); 1727 else { 1728 cpu_mfence(); 1729 for (i = 0; i < count; i++) { 1730 daddr = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(pages[i])); 1731 eva = daddr + PAGE_SIZE; 1732 for (; daddr < eva; daddr += cpu_clflush_line_size) 1733 clflush(daddr); 1734 } 1735 cpu_mfence(); 1736 } 1737 } 1738 1739 void 1740 pmap_invalidate_cache_range(vm_offset_t sva, vm_offset_t eva) 1741 { 1742 KASSERT((sva & PAGE_MASK) == 0, 1743 ("pmap_invalidate_cache_range: sva not page-aligned")); 1744 KASSERT((eva & PAGE_MASK) == 0, 1745 ("pmap_invalidate_cache_range: eva not page-aligned")); 1746 1747 if (cpu_feature & CPUID_SS) { 1748 ; /* If "Self Snoop" is supported, do nothing. */ 1749 } else { 1750 /* Globally invalidate caches */ 1751 cpu_wbinvd_on_all_cpus(); 1752 } 1753 } 1754 1755 /* 1756 * Invalidate the specified range of virtual memory on all cpus associated 1757 * with the pmap. 1758 */ 1759 void 1760 pmap_invalidate_range(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 1761 { 1762 pmap_inval_smp(pmap, sva, (eva - sva) >> PAGE_SHIFT, NULL, 0); 1763 } 1764 1765 /* 1766 * Add a list of wired pages to the kva. This routine is used for temporary 1767 * kernel mappings such as those found in buffer cache buffer. Page 1768 * modifications and accesses are not tracked or recorded. 1769 * 1770 * NOTE! Old mappings are simply overwritten, and we cannot assume relaxed 1771 * semantics as previous mappings may have been zerod without any 1772 * invalidation. 1773 * 1774 * The page *must* be wired. 1775 */ 1776 static __inline void 1777 _pmap_qenter(vm_offset_t beg_va, vm_page_t *m, int count, int doinval) 1778 { 1779 vm_offset_t end_va; 1780 vm_offset_t va; 1781 1782 end_va = beg_va + count * PAGE_SIZE; 1783 1784 for (va = beg_va; va < end_va; va += PAGE_SIZE) { 1785 pt_entry_t pte; 1786 pt_entry_t *ptep; 1787 1788 ptep = vtopte(va); 1789 pte = VM_PAGE_TO_PHYS(*m) | 1790 kernel_pmap.pmap_bits[PG_RW_IDX] | 1791 kernel_pmap.pmap_bits[PG_V_IDX] | 1792 kernel_pmap.pmap_cache_bits[(*m)->pat_mode]; 1793 // pgeflag; 1794 atomic_swap_long(ptep, pte); 1795 m++; 1796 } 1797 if (doinval) 1798 pmap_invalidate_range(&kernel_pmap, beg_va, end_va); 1799 } 1800 1801 void 1802 pmap_qenter(vm_offset_t beg_va, vm_page_t *m, int count) 1803 { 1804 _pmap_qenter(beg_va, m, count, 1); 1805 } 1806 1807 void 1808 pmap_qenter_noinval(vm_offset_t beg_va, vm_page_t *m, int count) 1809 { 1810 _pmap_qenter(beg_va, m, count, 0); 1811 } 1812 1813 /* 1814 * This routine jerks page mappings from the kernel -- it is meant only 1815 * for temporary mappings such as those found in buffer cache buffers. 1816 * No recording modified or access status occurs. 1817 * 1818 * MPSAFE, INTERRUPT SAFE (cluster callback) 1819 */ 1820 void 1821 pmap_qremove(vm_offset_t beg_va, int count) 1822 { 1823 vm_offset_t end_va; 1824 vm_offset_t va; 1825 1826 end_va = beg_va + count * PAGE_SIZE; 1827 1828 for (va = beg_va; va < end_va; va += PAGE_SIZE) { 1829 pt_entry_t *pte; 1830 1831 pte = vtopte(va); 1832 (void)pte_load_clear(pte); 1833 cpu_invlpg((void *)va); 1834 } 1835 pmap_invalidate_range(&kernel_pmap, beg_va, end_va); 1836 } 1837 1838 /* 1839 * This routine removes temporary kernel mappings, only invalidating them 1840 * on the current cpu. It should only be used under carefully controlled 1841 * conditions. 1842 */ 1843 void 1844 pmap_qremove_quick(vm_offset_t beg_va, int count) 1845 { 1846 vm_offset_t end_va; 1847 vm_offset_t va; 1848 1849 end_va = beg_va + count * PAGE_SIZE; 1850 1851 for (va = beg_va; va < end_va; va += PAGE_SIZE) { 1852 pt_entry_t *pte; 1853 1854 pte = vtopte(va); 1855 (void)pte_load_clear(pte); 1856 cpu_invlpg((void *)va); 1857 } 1858 } 1859 1860 /* 1861 * This routine removes temporary kernel mappings *without* invalidating 1862 * the TLB. It can only be used on permanent kva reservations such as those 1863 * found in buffer cache buffers, under carefully controlled circumstances. 1864 * 1865 * NOTE: Repopulating these KVAs requires unconditional invalidation. 1866 * (pmap_qenter() does unconditional invalidation). 1867 */ 1868 void 1869 pmap_qremove_noinval(vm_offset_t beg_va, int count) 1870 { 1871 vm_offset_t end_va; 1872 vm_offset_t va; 1873 1874 end_va = beg_va + count * PAGE_SIZE; 1875 1876 for (va = beg_va; va < end_va; va += PAGE_SIZE) { 1877 pt_entry_t *pte; 1878 1879 pte = vtopte(va); 1880 (void)pte_load_clear(pte); 1881 } 1882 } 1883 1884 /* 1885 * Create a new thread and optionally associate it with a (new) process. 1886 * NOTE! the new thread's cpu may not equal the current cpu. 1887 */ 1888 void 1889 pmap_init_thread(thread_t td) 1890 { 1891 /* enforce pcb placement & alignment */ 1892 td->td_pcb = (struct pcb *)(td->td_kstack + td->td_kstack_size) - 1; 1893 td->td_pcb = (struct pcb *)((intptr_t)td->td_pcb & ~(intptr_t)0xF); 1894 td->td_savefpu = &td->td_pcb->pcb_save; 1895 td->td_sp = (char *)td->td_pcb; /* no -16 */ 1896 } 1897 1898 /* 1899 * This routine directly affects the fork perf for a process. 1900 */ 1901 void 1902 pmap_init_proc(struct proc *p) 1903 { 1904 } 1905 1906 static void 1907 pmap_pinit_defaults(struct pmap *pmap) 1908 { 1909 bcopy(pmap_bits_default, pmap->pmap_bits, 1910 sizeof(pmap_bits_default)); 1911 bcopy(protection_codes, pmap->protection_codes, 1912 sizeof(protection_codes)); 1913 bcopy(pat_pte_index, pmap->pmap_cache_bits, 1914 sizeof(pat_pte_index)); 1915 pmap->pmap_cache_mask = X86_PG_NC_PWT | X86_PG_NC_PCD | X86_PG_PTE_PAT; 1916 pmap->copyinstr = std_copyinstr; 1917 pmap->copyin = std_copyin; 1918 pmap->copyout = std_copyout; 1919 pmap->fubyte = std_fubyte; 1920 pmap->subyte = std_subyte; 1921 pmap->fuword32 = std_fuword32; 1922 pmap->fuword64 = std_fuword64; 1923 pmap->suword32 = std_suword32; 1924 pmap->suword64 = std_suword64; 1925 pmap->swapu32 = std_swapu32; 1926 pmap->swapu64 = std_swapu64; 1927 } 1928 /* 1929 * Initialize pmap0/vmspace0. 1930 * 1931 * On architectures where the kernel pmap is not integrated into the user 1932 * process pmap, this pmap represents the process pmap, not the kernel pmap. 1933 * kernel_pmap should be used to directly access the kernel_pmap. 1934 */ 1935 void 1936 pmap_pinit0(struct pmap *pmap) 1937 { 1938 int i; 1939 1940 pmap->pm_pml4 = (pml4_entry_t *)(PTOV_OFFSET + KPML4phys); 1941 pmap->pm_count = 1; 1942 CPUMASK_ASSZERO(pmap->pm_active); 1943 pmap->pm_pvhint_pt = NULL; 1944 pmap->pm_pvhint_pte = NULL; 1945 RB_INIT(&pmap->pm_pvroot); 1946 spin_init(&pmap->pm_spin, "pmapinit0"); 1947 for (i = 0; i < PM_PLACEMARKS; ++i) 1948 pmap->pm_placemarks[i] = PM_NOPLACEMARK; 1949 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1950 pmap_pinit_defaults(pmap); 1951 } 1952 1953 /* 1954 * Initialize a preallocated and zeroed pmap structure, 1955 * such as one in a vmspace structure. 1956 */ 1957 static void 1958 pmap_pinit_simple(struct pmap *pmap) 1959 { 1960 int i; 1961 1962 /* 1963 * Misc initialization 1964 */ 1965 pmap->pm_count = 1; 1966 CPUMASK_ASSZERO(pmap->pm_active); 1967 pmap->pm_pvhint_pt = NULL; 1968 pmap->pm_pvhint_pte = NULL; 1969 pmap->pm_flags = PMAP_FLAG_SIMPLE; 1970 1971 pmap_pinit_defaults(pmap); 1972 1973 /* 1974 * Don't blow up locks/tokens on re-use (XXX fix/use drop code 1975 * for this). 1976 */ 1977 if (pmap->pm_pmlpv == NULL) { 1978 RB_INIT(&pmap->pm_pvroot); 1979 bzero(&pmap->pm_stats, sizeof pmap->pm_stats); 1980 spin_init(&pmap->pm_spin, "pmapinitsimple"); 1981 for (i = 0; i < PM_PLACEMARKS; ++i) 1982 pmap->pm_placemarks[i] = PM_NOPLACEMARK; 1983 } 1984 } 1985 1986 void 1987 pmap_pinit(struct pmap *pmap) 1988 { 1989 pv_entry_t pv; 1990 int j; 1991 1992 if (pmap->pm_pmlpv) { 1993 if (pmap->pmap_bits[TYPE_IDX] != REGULAR_PMAP) { 1994 pmap_puninit(pmap); 1995 } 1996 } 1997 1998 pmap_pinit_simple(pmap); 1999 pmap->pm_flags &= ~PMAP_FLAG_SIMPLE; 2000 2001 /* 2002 * No need to allocate page table space yet but we do need a valid 2003 * page directory table. 2004 */ 2005 if (pmap->pm_pml4 == NULL) { 2006 pmap->pm_pml4 = 2007 (pml4_entry_t *)kmem_alloc_pageable(&kernel_map, 2008 PAGE_SIZE, 2009 VM_SUBSYS_PML4); 2010 } 2011 2012 /* 2013 * Allocate the page directory page, which wires it even though 2014 * it isn't being entered into some higher level page table (it 2015 * being the highest level). If one is already cached we don't 2016 * have to do anything. 2017 */ 2018 if ((pv = pmap->pm_pmlpv) == NULL) { 2019 pv = pmap_allocpte(pmap, pmap_pml4_pindex(), NULL); 2020 pmap->pm_pmlpv = pv; 2021 pmap_kenter((vm_offset_t)pmap->pm_pml4, 2022 VM_PAGE_TO_PHYS(pv->pv_m)); 2023 pv_put(pv); 2024 2025 /* 2026 * Install DMAP and KMAP. 2027 */ 2028 for (j = 0; j < NDMPML4E; ++j) { 2029 pmap->pm_pml4[DMPML4I + j] = 2030 (DMPDPphys + ((vm_paddr_t)j << PAGE_SHIFT)) | 2031 pmap->pmap_bits[PG_RW_IDX] | 2032 pmap->pmap_bits[PG_V_IDX] | 2033 pmap->pmap_bits[PG_U_IDX]; 2034 } 2035 for (j = 0; j < NKPML4E; ++j) { 2036 pmap->pm_pml4[KPML4I + j] = 2037 (KPDPphys + ((vm_paddr_t)j << PAGE_SHIFT)) | 2038 pmap->pmap_bits[PG_RW_IDX] | 2039 pmap->pmap_bits[PG_V_IDX] | 2040 pmap->pmap_bits[PG_U_IDX]; 2041 } 2042 2043 /* 2044 * install self-referential address mapping entry 2045 */ 2046 pmap->pm_pml4[PML4PML4I] = VM_PAGE_TO_PHYS(pv->pv_m) | 2047 pmap->pmap_bits[PG_V_IDX] | 2048 pmap->pmap_bits[PG_RW_IDX] | 2049 pmap->pmap_bits[PG_A_IDX] | 2050 pmap->pmap_bits[PG_M_IDX]; 2051 } else { 2052 KKASSERT(pv->pv_m->flags & PG_MAPPED); 2053 KKASSERT(pv->pv_m->flags & PG_WRITEABLE); 2054 } 2055 KKASSERT(pmap->pm_pml4[255] == 0); 2056 KKASSERT(RB_ROOT(&pmap->pm_pvroot) == pv); 2057 KKASSERT(pv->pv_entry.rbe_left == NULL); 2058 KKASSERT(pv->pv_entry.rbe_right == NULL); 2059 } 2060 2061 /* 2062 * Clean up a pmap structure so it can be physically freed. This routine 2063 * is called by the vmspace dtor function. A great deal of pmap data is 2064 * left passively mapped to improve vmspace management so we have a bit 2065 * of cleanup work to do here. 2066 */ 2067 void 2068 pmap_puninit(pmap_t pmap) 2069 { 2070 pv_entry_t pv; 2071 vm_page_t p; 2072 2073 KKASSERT(CPUMASK_TESTZERO(pmap->pm_active)); 2074 if ((pv = pmap->pm_pmlpv) != NULL) { 2075 if (pv_hold_try(pv) == 0) 2076 pv_lock(pv); 2077 KKASSERT(pv == pmap->pm_pmlpv); 2078 p = pmap_remove_pv_page(pv); 2079 pv_free(pv, NULL); 2080 pv = NULL; /* safety */ 2081 pmap_kremove((vm_offset_t)pmap->pm_pml4); 2082 vm_page_busy_wait(p, FALSE, "pgpun"); 2083 KKASSERT(p->flags & (PG_FICTITIOUS|PG_UNMANAGED)); 2084 vm_page_unwire(p, 0); 2085 vm_page_flag_clear(p, PG_MAPPED | PG_WRITEABLE); 2086 2087 /* 2088 * XXX eventually clean out PML4 static entries and 2089 * use vm_page_free_zero() 2090 */ 2091 vm_page_free(p); 2092 pmap->pm_pmlpv = NULL; 2093 } 2094 if (pmap->pm_pml4) { 2095 KKASSERT(pmap->pm_pml4 != (void *)(PTOV_OFFSET + KPML4phys)); 2096 kmem_free(&kernel_map, (vm_offset_t)pmap->pm_pml4, PAGE_SIZE); 2097 pmap->pm_pml4 = NULL; 2098 } 2099 KKASSERT(pmap->pm_stats.resident_count == 0); 2100 KKASSERT(pmap->pm_stats.wired_count == 0); 2101 } 2102 2103 /* 2104 * This function is now unused (used to add the pmap to the pmap_list) 2105 */ 2106 void 2107 pmap_pinit2(struct pmap *pmap) 2108 { 2109 } 2110 2111 /* 2112 * This routine is called when various levels in the page table need to 2113 * be populated. This routine cannot fail. 2114 * 2115 * This function returns two locked pv_entry's, one representing the 2116 * requested pv and one representing the requested pv's parent pv. If 2117 * an intermediate page table does not exist it will be created, mapped, 2118 * wired, and the parent page table will be given an additional hold 2119 * count representing the presence of the child pv_entry. 2120 */ 2121 static 2122 pv_entry_t 2123 pmap_allocpte(pmap_t pmap, vm_pindex_t ptepindex, pv_entry_t *pvpp) 2124 { 2125 pt_entry_t *ptep; 2126 pv_entry_t pv; 2127 pv_entry_t pvp; 2128 pt_entry_t v; 2129 vm_pindex_t pt_pindex; 2130 vm_page_t m; 2131 int isnew; 2132 int ispt; 2133 2134 /* 2135 * If the pv already exists and we aren't being asked for the 2136 * parent page table page we can just return it. A locked+held pv 2137 * is returned. The pv will also have a second hold related to the 2138 * pmap association that we don't have to worry about. 2139 */ 2140 ispt = 0; 2141 pv = pv_alloc(pmap, ptepindex, &isnew); 2142 if (isnew == 0 && pvpp == NULL) 2143 return(pv); 2144 2145 /* 2146 * Special case terminal PVs. These are not page table pages so 2147 * no vm_page is allocated (the caller supplied the vm_page). If 2148 * pvpp is non-NULL we are being asked to also removed the pt_pv 2149 * for this pv. 2150 * 2151 * Note that pt_pv's are only returned for user VAs. We assert that 2152 * a pt_pv is not being requested for kernel VAs. The kernel 2153 * pre-wires all higher-level page tables so don't overload managed 2154 * higher-level page tables on top of it! 2155 */ 2156 if (ptepindex < pmap_pt_pindex(0)) { 2157 if (ptepindex >= NUPTE_USER) { 2158 /* kernel manages this manually for KVM */ 2159 KKASSERT(pvpp == NULL); 2160 } else { 2161 KKASSERT(pvpp != NULL); 2162 pt_pindex = NUPTE_TOTAL + (ptepindex >> NPTEPGSHIFT); 2163 pvp = pmap_allocpte(pmap, pt_pindex, NULL); 2164 if (isnew) 2165 vm_page_wire_quick(pvp->pv_m); 2166 *pvpp = pvp; 2167 } 2168 return(pv); 2169 } 2170 2171 /* 2172 * The kernel never uses managed PT/PD/PDP pages. 2173 */ 2174 KKASSERT(pmap != &kernel_pmap); 2175 2176 /* 2177 * Non-terminal PVs allocate a VM page to represent the page table, 2178 * so we have to resolve pvp and calculate ptepindex for the pvp 2179 * and then for the page table entry index in the pvp for 2180 * fall-through. 2181 */ 2182 if (ptepindex < pmap_pd_pindex(0)) { 2183 /* 2184 * pv is PT, pvp is PD 2185 */ 2186 ptepindex = (ptepindex - pmap_pt_pindex(0)) >> NPDEPGSHIFT; 2187 ptepindex += NUPTE_TOTAL + NUPT_TOTAL; 2188 pvp = pmap_allocpte(pmap, ptepindex, NULL); 2189 2190 /* 2191 * PT index in PD 2192 */ 2193 ptepindex = pv->pv_pindex - pmap_pt_pindex(0); 2194 ptepindex &= ((1ul << NPDEPGSHIFT) - 1); 2195 ispt = 1; 2196 } else if (ptepindex < pmap_pdp_pindex(0)) { 2197 /* 2198 * pv is PD, pvp is PDP 2199 * 2200 * SIMPLE PMAP NOTE: Simple pmaps do not allocate above 2201 * the PD. 2202 */ 2203 ptepindex = (ptepindex - pmap_pd_pindex(0)) >> NPDPEPGSHIFT; 2204 ptepindex += NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL; 2205 2206 if (pmap->pm_flags & PMAP_FLAG_SIMPLE) { 2207 KKASSERT(pvpp == NULL); 2208 pvp = NULL; 2209 } else { 2210 pvp = pmap_allocpte(pmap, ptepindex, NULL); 2211 } 2212 2213 /* 2214 * PD index in PDP 2215 */ 2216 ptepindex = pv->pv_pindex - pmap_pd_pindex(0); 2217 ptepindex &= ((1ul << NPDPEPGSHIFT) - 1); 2218 } else if (ptepindex < pmap_pml4_pindex()) { 2219 /* 2220 * pv is PDP, pvp is the root pml4 table 2221 */ 2222 pvp = pmap_allocpte(pmap, pmap_pml4_pindex(), NULL); 2223 2224 /* 2225 * PDP index in PML4 2226 */ 2227 ptepindex = pv->pv_pindex - pmap_pdp_pindex(0); 2228 ptepindex &= ((1ul << NPML4EPGSHIFT) - 1); 2229 } else { 2230 /* 2231 * pv represents the top-level PML4, there is no parent. 2232 */ 2233 pvp = NULL; 2234 } 2235 2236 if (isnew == 0) 2237 goto notnew; 2238 2239 /* 2240 * (isnew) is TRUE, pv is not terminal. 2241 * 2242 * (1) Add a wire count to the parent page table (pvp). 2243 * (2) Allocate a VM page for the page table. 2244 * (3) Enter the VM page into the parent page table. 2245 * 2246 * page table pages are marked PG_WRITEABLE and PG_MAPPED. 2247 */ 2248 if (pvp) 2249 vm_page_wire_quick(pvp->pv_m); 2250 2251 for (;;) { 2252 m = vm_page_alloc(NULL, pv->pv_pindex, 2253 VM_ALLOC_NORMAL | VM_ALLOC_SYSTEM | 2254 VM_ALLOC_INTERRUPT); 2255 if (m) 2256 break; 2257 vm_wait(0); 2258 } 2259 vm_page_wire(m); /* wire for mapping in parent */ 2260 vm_page_unmanage(m); /* m must be spinunlocked */ 2261 pmap_zero_page(VM_PAGE_TO_PHYS(m)); 2262 m->valid = VM_PAGE_BITS_ALL; 2263 2264 vm_page_spin_lock(m); 2265 pmap_page_stats_adding(m); 2266 TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list); 2267 pv->pv_m = m; 2268 vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE); 2269 vm_page_spin_unlock(m); 2270 2271 /* 2272 * (isnew) is TRUE, pv is not terminal. 2273 * 2274 * Wire the page into pvp. Bump the resident_count for the pmap. 2275 * There is no pvp for the top level, address the pm_pml4[] array 2276 * directly. 2277 * 2278 * If the caller wants the parent we return it, otherwise 2279 * we just put it away. 2280 * 2281 * No interlock is needed for pte 0 -> non-zero. 2282 * 2283 * In the situation where *ptep is valid we might have an unmanaged 2284 * page table page shared from another page table which we need to 2285 * unshare before installing our private page table page. 2286 */ 2287 if (pvp) { 2288 v = VM_PAGE_TO_PHYS(m) | 2289 (pmap->pmap_bits[PG_U_IDX] | 2290 pmap->pmap_bits[PG_RW_IDX] | 2291 pmap->pmap_bits[PG_V_IDX] | 2292 pmap->pmap_bits[PG_A_IDX] | 2293 pmap->pmap_bits[PG_M_IDX]); 2294 ptep = pv_pte_lookup(pvp, ptepindex); 2295 if (*ptep & pmap->pmap_bits[PG_V_IDX]) { 2296 pt_entry_t pte; 2297 2298 if (ispt == 0) { 2299 panic("pmap_allocpte: unexpected pte %p/%d", 2300 pvp, (int)ptepindex); 2301 } 2302 pte = pmap_inval_smp(pmap, (vm_offset_t)-1, 1, ptep, v); 2303 if (vm_page_unwire_quick( 2304 PHYS_TO_VM_PAGE(pte & PG_FRAME))) { 2305 panic("pmap_allocpte: shared pgtable " 2306 "pg bad wirecount"); 2307 } 2308 } else { 2309 pt_entry_t pte; 2310 2311 pte = atomic_swap_long(ptep, v); 2312 if (pte != 0) { 2313 kprintf("install pgtbl mixup 0x%016jx " 2314 "old/new 0x%016jx/0x%016jx\n", 2315 (intmax_t)ptepindex, pte, v); 2316 } 2317 } 2318 } 2319 vm_page_wakeup(m); 2320 2321 /* 2322 * (isnew) may be TRUE or FALSE, pv may or may not be terminal. 2323 */ 2324 notnew: 2325 if (pvp) { 2326 KKASSERT(pvp->pv_m != NULL); 2327 ptep = pv_pte_lookup(pvp, ptepindex); 2328 v = VM_PAGE_TO_PHYS(pv->pv_m) | 2329 (pmap->pmap_bits[PG_U_IDX] | 2330 pmap->pmap_bits[PG_RW_IDX] | 2331 pmap->pmap_bits[PG_V_IDX] | 2332 pmap->pmap_bits[PG_A_IDX] | 2333 pmap->pmap_bits[PG_M_IDX]); 2334 if (*ptep != v) { 2335 kprintf("mismatched upper level pt %016jx/%016jx\n", 2336 *ptep, v); 2337 } 2338 } 2339 if (pvpp) 2340 *pvpp = pvp; 2341 else if (pvp) 2342 pv_put(pvp); 2343 return (pv); 2344 } 2345 2346 /* 2347 * This version of pmap_allocpte() checks for possible segment optimizations 2348 * that would allow page-table sharing. It can be called for terminal 2349 * page or page table page ptepindex's. 2350 * 2351 * The function is called with page table page ptepindex's for fictitious 2352 * and unmanaged terminal pages. That is, we don't want to allocate a 2353 * terminal pv, we just want the pt_pv. pvpp is usually passed as NULL 2354 * for this case. 2355 * 2356 * This function can return a pv and *pvpp associated with the passed in pmap 2357 * OR a pv and *pvpp associated with the shared pmap. In the latter case 2358 * an unmanaged page table page will be entered into the pass in pmap. 2359 */ 2360 static 2361 pv_entry_t 2362 pmap_allocpte_seg(pmap_t pmap, vm_pindex_t ptepindex, pv_entry_t *pvpp, 2363 vm_map_entry_t entry, vm_offset_t va) 2364 { 2365 vm_object_t object; 2366 pmap_t obpmap; 2367 pmap_t *obpmapp; 2368 vm_pindex_t *pt_placemark; 2369 vm_offset_t b; 2370 pv_entry_t pte_pv; /* in original or shared pmap */ 2371 pv_entry_t pt_pv; /* in original or shared pmap */ 2372 pv_entry_t proc_pd_pv; /* in original pmap */ 2373 pv_entry_t proc_pt_pv; /* in original pmap */ 2374 pv_entry_t xpv; /* PT in shared pmap */ 2375 pd_entry_t *pt; /* PT entry in PD of original pmap */ 2376 pd_entry_t opte; /* contents of *pt */ 2377 pd_entry_t npte; /* contents of *pt */ 2378 vm_page_t m; 2379 int softhold; 2380 2381 /* 2382 * Basic tests, require a non-NULL vm_map_entry, require proper 2383 * alignment and type for the vm_map_entry, require that the 2384 * underlying object already be allocated. 2385 * 2386 * We allow almost any type of object to use this optimization. 2387 * The object itself does NOT have to be sized to a multiple of the 2388 * segment size, but the memory mapping does. 2389 * 2390 * XXX don't handle devices currently, because VM_PAGE_TO_PHYS() 2391 * won't work as expected. 2392 */ 2393 if (entry == NULL || 2394 pmap_mmu_optimize == 0 || /* not enabled */ 2395 (pmap->pm_flags & PMAP_HVM) || /* special pmap */ 2396 ptepindex >= pmap_pd_pindex(0) || /* not terminal or pt */ 2397 entry->inheritance != VM_INHERIT_SHARE || /* not shared */ 2398 entry->maptype != VM_MAPTYPE_NORMAL || /* weird map type */ 2399 entry->object.vm_object == NULL || /* needs VM object */ 2400 entry->object.vm_object->type == OBJT_DEVICE || /* ick */ 2401 entry->object.vm_object->type == OBJT_MGTDEVICE || /* ick */ 2402 (entry->offset & SEG_MASK) || /* must be aligned */ 2403 (entry->start & SEG_MASK)) { 2404 return(pmap_allocpte(pmap, ptepindex, pvpp)); 2405 } 2406 2407 /* 2408 * Make sure the full segment can be represented. 2409 */ 2410 b = va & ~(vm_offset_t)SEG_MASK; 2411 if (b < entry->start || b + SEG_SIZE > entry->end) 2412 return(pmap_allocpte(pmap, ptepindex, pvpp)); 2413 2414 /* 2415 * If the full segment can be represented dive the VM object's 2416 * shared pmap, allocating as required. 2417 */ 2418 object = entry->object.vm_object; 2419 2420 if (entry->protection & VM_PROT_WRITE) 2421 obpmapp = &object->md.pmap_rw; 2422 else 2423 obpmapp = &object->md.pmap_ro; 2424 2425 #ifdef PMAP_DEBUG2 2426 if (pmap_enter_debug > 0) { 2427 --pmap_enter_debug; 2428 kprintf("pmap_allocpte_seg: va=%jx prot %08x o=%p " 2429 "obpmapp %p %p\n", 2430 va, entry->protection, object, 2431 obpmapp, *obpmapp); 2432 kprintf("pmap_allocpte_seg: entry %p %jx-%jx\n", 2433 entry, entry->start, entry->end); 2434 } 2435 #endif 2436 2437 /* 2438 * We allocate what appears to be a normal pmap but because portions 2439 * of this pmap are shared with other unrelated pmaps we have to 2440 * set pm_active to point to all cpus. 2441 * 2442 * XXX Currently using pmap_spin to interlock the update, can't use 2443 * vm_object_hold/drop because the token might already be held 2444 * shared OR exclusive and we don't know. 2445 */ 2446 while ((obpmap = *obpmapp) == NULL) { 2447 obpmap = kmalloc(sizeof(*obpmap), M_OBJPMAP, M_WAITOK|M_ZERO); 2448 pmap_pinit_simple(obpmap); 2449 pmap_pinit2(obpmap); 2450 spin_lock(&pmap_spin); 2451 if (*obpmapp != NULL) { 2452 /* 2453 * Handle race 2454 */ 2455 spin_unlock(&pmap_spin); 2456 pmap_release(obpmap); 2457 pmap_puninit(obpmap); 2458 kfree(obpmap, M_OBJPMAP); 2459 obpmap = *obpmapp; /* safety */ 2460 } else { 2461 obpmap->pm_active = smp_active_mask; 2462 obpmap->pm_flags |= PMAP_SEGSHARED; 2463 *obpmapp = obpmap; 2464 spin_unlock(&pmap_spin); 2465 } 2466 } 2467 2468 /* 2469 * Layering is: PTE, PT, PD, PDP, PML4. We have to return the 2470 * pte/pt using the shared pmap from the object but also adjust 2471 * the process pmap's page table page as a side effect. 2472 */ 2473 2474 /* 2475 * Resolve the terminal PTE and PT in the shared pmap. This is what 2476 * we will return. This is true if ptepindex represents a terminal 2477 * page, otherwise pte_pv is actually the PT and pt_pv is actually 2478 * the PD. 2479 */ 2480 pt_pv = NULL; 2481 pte_pv = pmap_allocpte(obpmap, ptepindex, &pt_pv); 2482 softhold = 0; 2483 retry: 2484 if (ptepindex >= pmap_pt_pindex(0)) 2485 xpv = pte_pv; 2486 else 2487 xpv = pt_pv; 2488 2489 /* 2490 * Resolve the PD in the process pmap so we can properly share the 2491 * page table page. Lock order is bottom-up (leaf first)! 2492 * 2493 * NOTE: proc_pt_pv can be NULL. 2494 */ 2495 proc_pt_pv = pv_get(pmap, pmap_pt_pindex(b), &pt_placemark); 2496 proc_pd_pv = pmap_allocpte(pmap, pmap_pd_pindex(b), NULL); 2497 #ifdef PMAP_DEBUG2 2498 if (pmap_enter_debug > 0) { 2499 --pmap_enter_debug; 2500 kprintf("proc_pt_pv %p (wc %d) pd_pv %p va=%jx\n", 2501 proc_pt_pv, 2502 (proc_pt_pv ? proc_pt_pv->pv_m->wire_count : -1), 2503 proc_pd_pv, 2504 va); 2505 } 2506 #endif 2507 2508 /* 2509 * xpv is the page table page pv from the shared object 2510 * (for convenience), from above. 2511 * 2512 * Calculate the pte value for the PT to load into the process PD. 2513 * If we have to change it we must properly dispose of the previous 2514 * entry. 2515 */ 2516 pt = pv_pte_lookup(proc_pd_pv, pmap_pt_index(b)); 2517 npte = VM_PAGE_TO_PHYS(xpv->pv_m) | 2518 (pmap->pmap_bits[PG_U_IDX] | 2519 pmap->pmap_bits[PG_RW_IDX] | 2520 pmap->pmap_bits[PG_V_IDX] | 2521 pmap->pmap_bits[PG_A_IDX] | 2522 pmap->pmap_bits[PG_M_IDX]); 2523 2524 /* 2525 * Dispose of previous page table page if it was local to the 2526 * process pmap. If the old pt is not empty we cannot dispose of it 2527 * until we clean it out. This case should not arise very often so 2528 * it is not optimized. 2529 * 2530 * Leave pt_pv and pte_pv (in our object pmap) locked and intact 2531 * for the retry. 2532 */ 2533 if (proc_pt_pv) { 2534 pmap_inval_bulk_t bulk; 2535 2536 if (proc_pt_pv->pv_m->wire_count != 1) { 2537 /* 2538 * The page table has a bunch of stuff in it 2539 * which we have to scrap. 2540 */ 2541 if (softhold == 0) { 2542 softhold = 1; 2543 pmap_softhold(pmap); 2544 } 2545 pv_put(proc_pd_pv); 2546 pv_put(proc_pt_pv); 2547 pmap_remove(pmap, 2548 va & ~(vm_offset_t)SEG_MASK, 2549 (va + SEG_SIZE) & ~(vm_offset_t)SEG_MASK); 2550 } else { 2551 /* 2552 * The page table is empty and can be destroyed. 2553 * However, doing so leaves the pt slot unlocked, 2554 * so we have to loop-up to handle any races until 2555 * we get a NULL proc_pt_pv and a proper pt_placemark. 2556 */ 2557 pmap_inval_bulk_init(&bulk, proc_pt_pv->pv_pmap); 2558 pmap_release_pv(proc_pt_pv, proc_pd_pv, &bulk); 2559 pmap_inval_bulk_flush(&bulk); 2560 pv_put(proc_pd_pv); 2561 } 2562 goto retry; 2563 } 2564 2565 /* 2566 * Handle remaining cases. We are holding pt_placemark to lock 2567 * the page table page in the primary pmap while we manipulate 2568 * it. 2569 */ 2570 if (*pt == 0) { 2571 atomic_swap_long(pt, npte); 2572 vm_page_wire_quick(xpv->pv_m); /* shared pt -> proc */ 2573 vm_page_wire_quick(proc_pd_pv->pv_m); /* proc pd for sh pt */ 2574 atomic_add_long(&pmap->pm_stats.resident_count, 1); 2575 } else if (*pt != npte) { 2576 opte = pmap_inval_smp(pmap, (vm_offset_t)-1, 1, pt, npte); 2577 2578 #if 0 2579 opte = pte_load_clear(pt); 2580 KKASSERT(opte && opte != npte); 2581 2582 *pt = npte; 2583 #endif 2584 vm_page_wire_quick(xpv->pv_m); /* shared pt -> proc */ 2585 2586 /* 2587 * Clean up opte, bump the wire_count for the process 2588 * PD page representing the new entry if it was 2589 * previously empty. 2590 * 2591 * If the entry was not previously empty and we have 2592 * a PT in the proc pmap then opte must match that 2593 * pt. The proc pt must be retired (this is done 2594 * later on in this procedure). 2595 * 2596 * NOTE: replacing valid pte, wire_count on proc_pd_pv 2597 * stays the same. 2598 */ 2599 KKASSERT(opte & pmap->pmap_bits[PG_V_IDX]); 2600 m = PHYS_TO_VM_PAGE(opte & PG_FRAME); 2601 if (vm_page_unwire_quick(m)) { 2602 panic("pmap_allocpte_seg: " 2603 "bad wire count %p", 2604 m); 2605 } 2606 } 2607 2608 if (softhold) 2609 pmap_softdone(pmap); 2610 2611 /* 2612 * Remove our earmark on the page table page. 2613 */ 2614 pv_placemarker_wakeup(pmap, pt_placemark); 2615 2616 /* 2617 * The existing process page table was replaced and must be destroyed 2618 * here. 2619 */ 2620 if (proc_pd_pv) 2621 pv_put(proc_pd_pv); 2622 if (pvpp) 2623 *pvpp = pt_pv; 2624 else 2625 pv_put(pt_pv); 2626 return (pte_pv); 2627 } 2628 2629 /* 2630 * Release any resources held by the given physical map. 2631 * 2632 * Called when a pmap initialized by pmap_pinit is being released. Should 2633 * only be called if the map contains no valid mappings. 2634 */ 2635 struct pmap_release_info { 2636 pmap_t pmap; 2637 int retry; 2638 pv_entry_t pvp; 2639 }; 2640 2641 static int pmap_release_callback(pv_entry_t pv, void *data); 2642 2643 void 2644 pmap_release(struct pmap *pmap) 2645 { 2646 struct pmap_release_info info; 2647 2648 KASSERT(CPUMASK_TESTZERO(pmap->pm_active), 2649 ("pmap still active! %016jx", 2650 (uintmax_t)CPUMASK_LOWMASK(pmap->pm_active))); 2651 2652 /* 2653 * There is no longer a pmap_list, if there were we would remove the 2654 * pmap from it here. 2655 */ 2656 2657 /* 2658 * Pull pv's off the RB tree in order from low to high and release 2659 * each page. 2660 */ 2661 info.pmap = pmap; 2662 do { 2663 info.retry = 0; 2664 info.pvp = NULL; 2665 2666 spin_lock(&pmap->pm_spin); 2667 RB_SCAN(pv_entry_rb_tree, &pmap->pm_pvroot, NULL, 2668 pmap_release_callback, &info); 2669 spin_unlock(&pmap->pm_spin); 2670 2671 if (info.pvp) 2672 pv_put(info.pvp); 2673 } while (info.retry); 2674 2675 2676 /* 2677 * One resident page (the pml4 page) should remain. 2678 * No wired pages should remain. 2679 */ 2680 #if 1 2681 if (pmap->pm_stats.resident_count != 2682 ((pmap->pm_flags & PMAP_FLAG_SIMPLE) ? 0 : 1) || 2683 pmap->pm_stats.wired_count != 0) { 2684 kprintf("fatal pmap problem - pmap %p flags %08x " 2685 "rescnt=%jd wirecnt=%jd\n", 2686 pmap, 2687 pmap->pm_flags, 2688 pmap->pm_stats.resident_count, 2689 pmap->pm_stats.wired_count); 2690 tsleep(pmap, 0, "DEAD", 0); 2691 } 2692 #else 2693 KKASSERT(pmap->pm_stats.resident_count == 2694 ((pmap->pm_flags & PMAP_FLAG_SIMPLE) ? 0 : 1)); 2695 KKASSERT(pmap->pm_stats.wired_count == 0); 2696 #endif 2697 } 2698 2699 /* 2700 * Called from low to high. We must cache the proper parent pv so we 2701 * can adjust its wired count. 2702 */ 2703 static int 2704 pmap_release_callback(pv_entry_t pv, void *data) 2705 { 2706 struct pmap_release_info *info = data; 2707 pmap_t pmap = info->pmap; 2708 vm_pindex_t pindex; 2709 int r; 2710 2711 /* 2712 * Acquire a held and locked pv, check for release race 2713 */ 2714 pindex = pv->pv_pindex; 2715 if (info->pvp == pv) { 2716 spin_unlock(&pmap->pm_spin); 2717 info->pvp = NULL; 2718 } else if (pv_hold_try(pv)) { 2719 spin_unlock(&pmap->pm_spin); 2720 } else { 2721 spin_unlock(&pmap->pm_spin); 2722 pv_lock(pv); 2723 pv_put(pv); 2724 info->retry = 1; 2725 spin_lock(&pmap->pm_spin); 2726 2727 return -1; 2728 } 2729 KKASSERT(pv->pv_pmap == pmap && pindex == pv->pv_pindex); 2730 2731 if (pv->pv_pindex < pmap_pt_pindex(0)) { 2732 /* 2733 * I am PTE, parent is PT 2734 */ 2735 pindex = pv->pv_pindex >> NPTEPGSHIFT; 2736 pindex += NUPTE_TOTAL; 2737 } else if (pv->pv_pindex < pmap_pd_pindex(0)) { 2738 /* 2739 * I am PT, parent is PD 2740 */ 2741 pindex = (pv->pv_pindex - NUPTE_TOTAL) >> NPDEPGSHIFT; 2742 pindex += NUPTE_TOTAL + NUPT_TOTAL; 2743 } else if (pv->pv_pindex < pmap_pdp_pindex(0)) { 2744 /* 2745 * I am PD, parent is PDP 2746 */ 2747 pindex = (pv->pv_pindex - NUPTE_TOTAL - NUPT_TOTAL) >> 2748 NPDPEPGSHIFT; 2749 pindex += NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL; 2750 } else if (pv->pv_pindex < pmap_pml4_pindex()) { 2751 /* 2752 * I am PDP, parent is PML4 (there's only one) 2753 */ 2754 #if 0 2755 pindex = (pv->pv_pindex - NUPTE_TOTAL - NUPT_TOTAL - 2756 NUPD_TOTAL) >> NPML4EPGSHIFT; 2757 pindex += NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL + NUPDP_TOTAL; 2758 #endif 2759 pindex = pmap_pml4_pindex(); 2760 } else { 2761 /* 2762 * parent is NULL 2763 */ 2764 if (info->pvp) { 2765 pv_put(info->pvp); 2766 info->pvp = NULL; 2767 } 2768 pindex = 0; 2769 } 2770 if (pindex) { 2771 if (info->pvp && info->pvp->pv_pindex != pindex) { 2772 pv_put(info->pvp); 2773 info->pvp = NULL; 2774 } 2775 if (info->pvp == NULL) 2776 info->pvp = pv_get(pmap, pindex, NULL); 2777 } else { 2778 if (info->pvp) { 2779 pv_put(info->pvp); 2780 info->pvp = NULL; 2781 } 2782 } 2783 r = pmap_release_pv(pv, info->pvp, NULL); 2784 spin_lock(&pmap->pm_spin); 2785 2786 return(r); 2787 } 2788 2789 /* 2790 * Called with held (i.e. also locked) pv. This function will dispose of 2791 * the lock along with the pv. 2792 * 2793 * If the caller already holds the locked parent page table for pv it 2794 * must pass it as pvp, allowing us to avoid a deadlock, else it can 2795 * pass NULL for pvp. 2796 */ 2797 static int 2798 pmap_release_pv(pv_entry_t pv, pv_entry_t pvp, pmap_inval_bulk_t *bulk) 2799 { 2800 vm_page_t p; 2801 2802 /* 2803 * The pmap is currently not spinlocked, pv is held+locked. 2804 * Remove the pv's page from its parent's page table. The 2805 * parent's page table page's wire_count will be decremented. 2806 * 2807 * This will clean out the pte at any level of the page table. 2808 * If smp != 0 all cpus are affected. 2809 * 2810 * Do not tear-down recursively, its faster to just let the 2811 * release run its course. 2812 */ 2813 pmap_remove_pv_pte(pv, pvp, bulk, 0); 2814 2815 /* 2816 * Terminal pvs are unhooked from their vm_pages. Because 2817 * terminal pages aren't page table pages they aren't wired 2818 * by us, so we have to be sure not to unwire them either. 2819 */ 2820 if (pv->pv_pindex < pmap_pt_pindex(0)) { 2821 pmap_remove_pv_page(pv); 2822 goto skip; 2823 } 2824 2825 /* 2826 * We leave the top-level page table page cached, wired, and 2827 * mapped in the pmap until the dtor function (pmap_puninit()) 2828 * gets called. 2829 * 2830 * Since we are leaving the top-level pv intact we need 2831 * to break out of what would otherwise be an infinite loop. 2832 */ 2833 if (pv->pv_pindex == pmap_pml4_pindex()) { 2834 pv_put(pv); 2835 return(-1); 2836 } 2837 2838 /* 2839 * For page table pages (other than the top-level page), 2840 * remove and free the vm_page. The representitive mapping 2841 * removed above by pmap_remove_pv_pte() did not undo the 2842 * last wire_count so we have to do that as well. 2843 */ 2844 p = pmap_remove_pv_page(pv); 2845 vm_page_busy_wait(p, FALSE, "pmaprl"); 2846 if (p->wire_count != 1) { 2847 kprintf("p->wire_count was %016lx %d\n", 2848 pv->pv_pindex, p->wire_count); 2849 } 2850 KKASSERT(p->wire_count == 1); 2851 KKASSERT(p->flags & PG_UNMANAGED); 2852 2853 vm_page_unwire(p, 0); 2854 KKASSERT(p->wire_count == 0); 2855 2856 vm_page_free(p); 2857 skip: 2858 pv_free(pv, pvp); 2859 2860 return 0; 2861 } 2862 2863 /* 2864 * This function will remove the pte associated with a pv from its parent. 2865 * Terminal pv's are supported. All cpus specified by (bulk) are properly 2866 * invalidated. 2867 * 2868 * The wire count will be dropped on the parent page table. The wire 2869 * count on the page being removed (pv->pv_m) from the parent page table 2870 * is NOT touched. Note that terminal pages will not have any additional 2871 * wire counts while page table pages will have at least one representing 2872 * the mapping, plus others representing sub-mappings. 2873 * 2874 * NOTE: Cannot be called on kernel page table pages, only KVM terminal 2875 * pages and user page table and terminal pages. 2876 * 2877 * NOTE: The pte being removed might be unmanaged, and the pv supplied might 2878 * be freshly allocated and not imply that the pte is managed. In this 2879 * case pv->pv_m should be NULL. 2880 * 2881 * The pv must be locked. The pvp, if supplied, must be locked. All 2882 * supplied pv's will remain locked on return. 2883 * 2884 * XXX must lock parent pv's if they exist to remove pte XXX 2885 */ 2886 static 2887 void 2888 pmap_remove_pv_pte(pv_entry_t pv, pv_entry_t pvp, pmap_inval_bulk_t *bulk, 2889 int destroy) 2890 { 2891 vm_pindex_t ptepindex = pv->pv_pindex; 2892 pmap_t pmap = pv->pv_pmap; 2893 vm_page_t p; 2894 int gotpvp = 0; 2895 2896 KKASSERT(pmap); 2897 2898 if (ptepindex == pmap_pml4_pindex()) { 2899 /* 2900 * We are the top level PML4E table, there is no parent. 2901 */ 2902 p = pmap->pm_pmlpv->pv_m; 2903 KKASSERT(pv->pv_m == p); /* debugging */ 2904 } else if (ptepindex >= pmap_pdp_pindex(0)) { 2905 /* 2906 * Remove a PDP page from the PML4E. This can only occur 2907 * with user page tables. We do not have to lock the 2908 * pml4 PV so just ignore pvp. 2909 */ 2910 vm_pindex_t pml4_pindex; 2911 vm_pindex_t pdp_index; 2912 pml4_entry_t *pdp; 2913 2914 pdp_index = ptepindex - pmap_pdp_pindex(0); 2915 if (pvp == NULL) { 2916 pml4_pindex = pmap_pml4_pindex(); 2917 pvp = pv_get(pv->pv_pmap, pml4_pindex, NULL); 2918 KKASSERT(pvp); 2919 gotpvp = 1; 2920 } 2921 2922 pdp = &pmap->pm_pml4[pdp_index & ((1ul << NPML4EPGSHIFT) - 1)]; 2923 KKASSERT((*pdp & pmap->pmap_bits[PG_V_IDX]) != 0); 2924 p = PHYS_TO_VM_PAGE(*pdp & PG_FRAME); 2925 pmap_inval_bulk(bulk, (vm_offset_t)-1, pdp, 0); 2926 KKASSERT(pv->pv_m == p); /* debugging */ 2927 } else if (ptepindex >= pmap_pd_pindex(0)) { 2928 /* 2929 * Remove a PD page from the PDP 2930 * 2931 * SIMPLE PMAP NOTE: Non-existant pvp's are ok in the case 2932 * of a simple pmap because it stops at 2933 * the PD page. 2934 */ 2935 vm_pindex_t pdp_pindex; 2936 vm_pindex_t pd_index; 2937 pdp_entry_t *pd; 2938 2939 pd_index = ptepindex - pmap_pd_pindex(0); 2940 2941 if (pvp == NULL) { 2942 pdp_pindex = NUPTE_TOTAL + NUPT_TOTAL + NUPD_TOTAL + 2943 (pd_index >> NPML4EPGSHIFT); 2944 pvp = pv_get(pv->pv_pmap, pdp_pindex, NULL); 2945 gotpvp = 1; 2946 } 2947 2948 if (pvp) { 2949 pd = pv_pte_lookup(pvp, pd_index & 2950 ((1ul << NPDPEPGSHIFT) - 1)); 2951 KKASSERT((*pd & pmap->pmap_bits[PG_V_IDX]) != 0); 2952 p = PHYS_TO_VM_PAGE(*pd & PG_FRAME); 2953 pmap_inval_bulk(bulk, (vm_offset_t)-1, pd, 0); 2954 } else { 2955 KKASSERT(pmap->pm_flags & PMAP_FLAG_SIMPLE); 2956 p = pv->pv_m; /* degenerate test later */ 2957 } 2958 KKASSERT(pv->pv_m == p); /* debugging */ 2959 } else if (ptepindex >= pmap_pt_pindex(0)) { 2960 /* 2961 * Remove a PT page from the PD 2962 */ 2963 vm_pindex_t pd_pindex; 2964 vm_pindex_t pt_index; 2965 pd_entry_t *pt; 2966 2967 pt_index = ptepindex - pmap_pt_pindex(0); 2968 2969 if (pvp == NULL) { 2970 pd_pindex = NUPTE_TOTAL + NUPT_TOTAL + 2971 (pt_index >> NPDPEPGSHIFT); 2972 pvp = pv_get(pv->pv_pmap, pd_pindex, NULL); 2973 KKASSERT(pvp); 2974 gotpvp = 1; 2975 } 2976 2977 pt = pv_pte_lookup(pvp, pt_index & ((1ul << NPDPEPGSHIFT) - 1)); 2978 #if 0 2979 KASSERT((*pt & pmap->pmap_bits[PG_V_IDX]) != 0, 2980 ("*pt unexpectedly invalid %016jx " 2981 "gotpvp=%d ptepindex=%ld ptindex=%ld pv=%p pvp=%p", 2982 *pt, gotpvp, ptepindex, pt_index, pv, pvp)); 2983 p = PHYS_TO_VM_PAGE(*pt & PG_FRAME); 2984 #else 2985 if ((*pt & pmap->pmap_bits[PG_V_IDX]) == 0) { 2986 kprintf("*pt unexpectedly invalid %016jx " 2987 "gotpvp=%d ptepindex=%ld ptindex=%ld " 2988 "pv=%p pvp=%p\n", 2989 *pt, gotpvp, ptepindex, pt_index, pv, pvp); 2990 tsleep(pt, 0, "DEAD", 0); 2991 p = pv->pv_m; 2992 } else { 2993 p = PHYS_TO_VM_PAGE(*pt & PG_FRAME); 2994 } 2995 #endif 2996 pmap_inval_bulk(bulk, (vm_offset_t)-1, pt, 0); 2997 KKASSERT(pv->pv_m == p); /* debugging */ 2998 } else { 2999 /* 3000 * Remove a PTE from the PT page. The PV might exist even if 3001 * the PTE is not managed, in whichcase pv->pv_m should be 3002 * NULL. 3003 * 3004 * NOTE: Userland pmaps manage the parent PT/PD/PDP page 3005 * table pages but the kernel_pmap does not. 3006 * 3007 * NOTE: pv's must be locked bottom-up to avoid deadlocking. 3008 * pv is a pte_pv so we can safely lock pt_pv. 3009 * 3010 * NOTE: FICTITIOUS pages may have multiple physical mappings 3011 * so PHYS_TO_VM_PAGE() will not necessarily work for 3012 * terminal ptes. 3013 */ 3014 vm_pindex_t pt_pindex; 3015 pt_entry_t *ptep; 3016 pt_entry_t pte; 3017 vm_offset_t va; 3018 3019 pt_pindex = ptepindex >> NPTEPGSHIFT; 3020 va = (vm_offset_t)ptepindex << PAGE_SHIFT; 3021 3022 if (ptepindex >= NUPTE_USER) { 3023 ptep = vtopte(ptepindex << PAGE_SHIFT); 3024 KKASSERT(pvp == NULL); 3025 /* pvp remains NULL */ 3026 } else { 3027 if (pvp == NULL) { 3028 pt_pindex = NUPTE_TOTAL + 3029 (ptepindex >> NPDPEPGSHIFT); 3030 pvp = pv_get(pv->pv_pmap, pt_pindex, NULL); 3031 KKASSERT(pvp); 3032 gotpvp = 1; 3033 } 3034 ptep = pv_pte_lookup(pvp, ptepindex & 3035 ((1ul << NPDPEPGSHIFT) - 1)); 3036 } 3037 pte = pmap_inval_bulk(bulk, va, ptep, 0); 3038 if (bulk == NULL) /* XXX */ 3039 cpu_invlpg((void *)va); /* XXX */ 3040 3041 /* 3042 * Now update the vm_page_t 3043 */ 3044 if ((pte & pmap->pmap_bits[PG_MANAGED_IDX]) && 3045 (pte & pmap->pmap_bits[PG_V_IDX])) { 3046 /* 3047 * Valid managed page, adjust (p). 3048 */ 3049 if (pte & pmap->pmap_bits[PG_DEVICE_IDX]) { 3050 p = pv->pv_m; 3051 } else { 3052 p = PHYS_TO_VM_PAGE(pte & PG_FRAME); 3053 KKASSERT(pv->pv_m == p); 3054 } 3055 if (pte & pmap->pmap_bits[PG_M_IDX]) { 3056 if (pmap_track_modified(ptepindex)) 3057 vm_page_dirty(p); 3058 } 3059 if (pte & pmap->pmap_bits[PG_A_IDX]) { 3060 vm_page_flag_set(p, PG_REFERENCED); 3061 } 3062 } else { 3063 /* 3064 * Unmanaged page, do not try to adjust the vm_page_t. 3065 * pv could be freshly allocated for a pmap_enter(), 3066 * replacing an unmanaged page with a managed one. 3067 * 3068 * pv->pv_m might reflect the new page and not the 3069 * existing page. 3070 * 3071 * We could extract p from the physical address and 3072 * adjust it but we explicitly do not for unmanaged 3073 * pages. 3074 */ 3075 p = NULL; 3076 } 3077 if (pte & pmap->pmap_bits[PG_W_IDX]) 3078 atomic_add_long(&pmap->pm_stats.wired_count, -1); 3079 if (pte & pmap->pmap_bits[PG_G_IDX]) 3080 cpu_invlpg((void *)va); 3081 } 3082 3083 /* 3084 * If requested, scrap the underlying pv->pv_m and the underlying 3085 * pv. If this is a page-table-page we must also free the page. 3086 * 3087 * pvp must be returned locked. 3088 */ 3089 if (destroy == 1) { 3090 /* 3091 * page table page (PT, PD, PDP, PML4), caller was responsible 3092 * for testing wired_count. 3093 */ 3094 KKASSERT(pv->pv_m->wire_count == 1); 3095 p = pmap_remove_pv_page(pv); 3096 pv_free(pv, pvp); 3097 pv = NULL; 3098 3099 vm_page_busy_wait(p, FALSE, "pgpun"); 3100 vm_page_unwire(p, 0); 3101 vm_page_flag_clear(p, PG_MAPPED | PG_WRITEABLE); 3102 vm_page_free(p); 3103 } else if (destroy == 2) { 3104 /* 3105 * Normal page, remove from pmap and leave the underlying 3106 * page untouched. 3107 */ 3108 pmap_remove_pv_page(pv); 3109 pv_free(pv, pvp); 3110 pv = NULL; /* safety */ 3111 } 3112 3113 /* 3114 * If we acquired pvp ourselves then we are responsible for 3115 * recursively deleting it. 3116 */ 3117 if (pvp && gotpvp) { 3118 /* 3119 * Recursively destroy higher-level page tables. 3120 * 3121 * This is optional. If we do not, they will still 3122 * be destroyed when the process exits. 3123 * 3124 * NOTE: Do not destroy pv_entry's with extra hold refs, 3125 * a caller may have unlocked it and intends to 3126 * continue to use it. 3127 */ 3128 if (pmap_dynamic_delete && 3129 pvp->pv_m && 3130 pvp->pv_m->wire_count == 1 && 3131 (pvp->pv_hold & PV_HOLD_MASK) == 2 && 3132 pvp->pv_pindex != pmap_pml4_pindex()) { 3133 if (pmap_dynamic_delete == 2) 3134 kprintf("A %jd %08x\n", pvp->pv_pindex, pvp->pv_hold); 3135 if (pmap != &kernel_pmap) { 3136 pmap_remove_pv_pte(pvp, NULL, bulk, 1); 3137 pvp = NULL; /* safety */ 3138 } else { 3139 kprintf("Attempt to remove kernel_pmap pindex " 3140 "%jd\n", pvp->pv_pindex); 3141 pv_put(pvp); 3142 } 3143 } else { 3144 pv_put(pvp); 3145 } 3146 } 3147 } 3148 3149 /* 3150 * Remove the vm_page association to a pv. The pv must be locked. 3151 */ 3152 static 3153 vm_page_t 3154 pmap_remove_pv_page(pv_entry_t pv) 3155 { 3156 vm_page_t m; 3157 3158 m = pv->pv_m; 3159 vm_page_spin_lock(m); 3160 KKASSERT(m && m == pv->pv_m); 3161 pv->pv_m = NULL; 3162 TAILQ_REMOVE(&m->md.pv_list, pv, pv_list); 3163 pmap_page_stats_deleting(m); 3164 if (TAILQ_EMPTY(&m->md.pv_list)) 3165 vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE); 3166 vm_page_spin_unlock(m); 3167 3168 return(m); 3169 } 3170 3171 /* 3172 * Grow the number of kernel page table entries, if needed. 3173 * 3174 * This routine is always called to validate any address space 3175 * beyond KERNBASE (for kldloads). kernel_vm_end only governs the address 3176 * space below KERNBASE. 3177 * 3178 * kernel_map must be locked exclusively by the caller. 3179 */ 3180 void 3181 pmap_growkernel(vm_offset_t kstart, vm_offset_t kend) 3182 { 3183 vm_paddr_t paddr; 3184 vm_offset_t ptppaddr; 3185 vm_page_t nkpg; 3186 pd_entry_t *pt, newpt; 3187 pdp_entry_t *pd, newpd; 3188 int update_kernel_vm_end; 3189 3190 /* 3191 * bootstrap kernel_vm_end on first real VM use 3192 */ 3193 if (kernel_vm_end == 0) { 3194 kernel_vm_end = VM_MIN_KERNEL_ADDRESS; 3195 3196 for (;;) { 3197 pt = pmap_pt(&kernel_pmap, kernel_vm_end); 3198 if (pt == NULL) 3199 break; 3200 if ((*pt & kernel_pmap.pmap_bits[PG_V_IDX]) == 0) 3201 break; 3202 kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & 3203 ~(vm_offset_t)(PAGE_SIZE * NPTEPG - 1); 3204 if (kernel_vm_end - 1 >= kernel_map.max_offset) { 3205 kernel_vm_end = kernel_map.max_offset; 3206 break; 3207 } 3208 } 3209 } 3210 3211 /* 3212 * Fill in the gaps. kernel_vm_end is only adjusted for ranges 3213 * below KERNBASE. Ranges above KERNBASE are kldloaded and we 3214 * do not want to force-fill 128G worth of page tables. 3215 */ 3216 if (kstart < KERNBASE) { 3217 if (kstart > kernel_vm_end) 3218 kstart = kernel_vm_end; 3219 KKASSERT(kend <= KERNBASE); 3220 update_kernel_vm_end = 1; 3221 } else { 3222 update_kernel_vm_end = 0; 3223 } 3224 3225 kstart = rounddown2(kstart, (vm_offset_t)(PAGE_SIZE * NPTEPG)); 3226 kend = roundup2(kend, (vm_offset_t)(PAGE_SIZE * NPTEPG)); 3227 3228 if (kend - 1 >= kernel_map.max_offset) 3229 kend = kernel_map.max_offset; 3230 3231 while (kstart < kend) { 3232 pt = pmap_pt(&kernel_pmap, kstart); 3233 if (pt == NULL) { 3234 /* 3235 * We need a new PD entry 3236 */ 3237 nkpg = vm_page_alloc(NULL, mycpu->gd_rand_incr++, 3238 VM_ALLOC_NORMAL | 3239 VM_ALLOC_SYSTEM | 3240 VM_ALLOC_INTERRUPT); 3241 if (nkpg == NULL) { 3242 panic("pmap_growkernel: no memory to grow " 3243 "kernel"); 3244 } 3245 paddr = VM_PAGE_TO_PHYS(nkpg); 3246 pmap_zero_page(paddr); 3247 pd = pmap_pd(&kernel_pmap, kstart); 3248 3249 newpd = (pdp_entry_t) 3250 (paddr | 3251 kernel_pmap.pmap_bits[PG_V_IDX] | 3252 kernel_pmap.pmap_bits[PG_RW_IDX] | 3253 kernel_pmap.pmap_bits[PG_A_IDX] | 3254 kernel_pmap.pmap_bits[PG_M_IDX]); 3255 atomic_swap_long(pd, newpd); 3256 3257 #if 0 3258 kprintf("NEWPD pd=%p pde=%016jx phys=%016jx\n", 3259 pd, newpd, paddr); 3260 #endif 3261 3262 continue; /* try again */ 3263 } 3264 3265 if ((*pt & kernel_pmap.pmap_bits[PG_V_IDX]) != 0) { 3266 kstart = (kstart + PAGE_SIZE * NPTEPG) & 3267 ~(vm_offset_t)(PAGE_SIZE * NPTEPG - 1); 3268 if (kstart - 1 >= kernel_map.max_offset) { 3269 kstart = kernel_map.max_offset; 3270 break; 3271 } 3272 continue; 3273 } 3274 3275 /* 3276 * We need a new PT 3277 * 3278 * This index is bogus, but out of the way 3279 */ 3280 nkpg = vm_page_alloc(NULL, mycpu->gd_rand_incr++, 3281 VM_ALLOC_NORMAL | 3282 VM_ALLOC_SYSTEM | 3283 VM_ALLOC_INTERRUPT); 3284 if (nkpg == NULL) 3285 panic("pmap_growkernel: no memory to grow kernel"); 3286 3287 vm_page_wire(nkpg); 3288 ptppaddr = VM_PAGE_TO_PHYS(nkpg); 3289 pmap_zero_page(ptppaddr); 3290 newpt = (pd_entry_t)(ptppaddr | 3291 kernel_pmap.pmap_bits[PG_V_IDX] | 3292 kernel_pmap.pmap_bits[PG_RW_IDX] | 3293 kernel_pmap.pmap_bits[PG_A_IDX] | 3294 kernel_pmap.pmap_bits[PG_M_IDX]); 3295 atomic_swap_long(pt, newpt); 3296 3297 kstart = (kstart + PAGE_SIZE * NPTEPG) & 3298 ~(vm_offset_t)(PAGE_SIZE * NPTEPG - 1); 3299 3300 if (kstart - 1 >= kernel_map.max_offset) { 3301 kstart = kernel_map.max_offset; 3302 break; 3303 } 3304 } 3305 3306 /* 3307 * Only update kernel_vm_end for areas below KERNBASE. 3308 */ 3309 if (update_kernel_vm_end && kernel_vm_end < kstart) 3310 kernel_vm_end = kstart; 3311 } 3312 3313 /* 3314 * Add a reference to the specified pmap. 3315 */ 3316 void 3317 pmap_reference(pmap_t pmap) 3318 { 3319 if (pmap != NULL) 3320 atomic_add_int(&pmap->pm_count, 1); 3321 } 3322 3323 /*************************************************** 3324 * page management routines. 3325 ***************************************************/ 3326 3327 /* 3328 * Hold a pv without locking it 3329 */ 3330 static void 3331 pv_hold(pv_entry_t pv) 3332 { 3333 atomic_add_int(&pv->pv_hold, 1); 3334 } 3335 3336 /* 3337 * Hold a pv_entry, preventing its destruction. TRUE is returned if the pv 3338 * was successfully locked, FALSE if it wasn't. The caller must dispose of 3339 * the pv properly. 3340 * 3341 * Either the pmap->pm_spin or the related vm_page_spin (if traversing a 3342 * pv list via its page) must be held by the caller in order to stabilize 3343 * the pv. 3344 */ 3345 static int 3346 _pv_hold_try(pv_entry_t pv PMAP_DEBUG_DECL) 3347 { 3348 u_int count; 3349 3350 /* 3351 * Critical path shortcut expects pv to already have one ref 3352 * (for the pv->pv_pmap). 3353 */ 3354 if (atomic_cmpset_int(&pv->pv_hold, 1, PV_HOLD_LOCKED | 2)) { 3355 #ifdef PMAP_DEBUG 3356 pv->pv_func = func; 3357 pv->pv_line = lineno; 3358 #endif 3359 return TRUE; 3360 } 3361 3362 for (;;) { 3363 count = pv->pv_hold; 3364 cpu_ccfence(); 3365 if ((count & PV_HOLD_LOCKED) == 0) { 3366 if (atomic_cmpset_int(&pv->pv_hold, count, 3367 (count + 1) | PV_HOLD_LOCKED)) { 3368 #ifdef PMAP_DEBUG 3369 pv->pv_func = func; 3370 pv->pv_line = lineno; 3371 #endif 3372 return TRUE; 3373 } 3374 } else { 3375 if (atomic_cmpset_int(&pv->pv_hold, count, count + 1)) 3376 return FALSE; 3377 } 3378 /* retry */ 3379 } 3380 } 3381 3382 /* 3383 * Drop a previously held pv_entry which could not be locked, allowing its 3384 * destruction. 3385 * 3386 * Must not be called with a spinlock held as we might zfree() the pv if it 3387 * is no longer associated with a pmap and this was the last hold count. 3388 */ 3389 static void 3390 pv_drop(pv_entry_t pv) 3391 { 3392 u_int count; 3393 3394 for (;;) { 3395 count = pv->pv_hold; 3396 cpu_ccfence(); 3397 KKASSERT((count & PV_HOLD_MASK) > 0); 3398 KKASSERT((count & (PV_HOLD_LOCKED | PV_HOLD_MASK)) != 3399 (PV_HOLD_LOCKED | 1)); 3400 if (atomic_cmpset_int(&pv->pv_hold, count, count - 1)) { 3401 if ((count & PV_HOLD_MASK) == 1) { 3402 #ifdef PMAP_DEBUG2 3403 if (pmap_enter_debug > 0) { 3404 --pmap_enter_debug; 3405 kprintf("pv_drop: free pv %p\n", pv); 3406 } 3407 #endif 3408 KKASSERT(count == 1); 3409 KKASSERT(pv->pv_pmap == NULL); 3410 zfree(pvzone, pv); 3411 } 3412 return; 3413 } 3414 /* retry */ 3415 } 3416 } 3417 3418 /* 3419 * Find or allocate the requested PV entry, returning a locked, held pv. 3420 * 3421 * If (*isnew) is non-zero, the returned pv will have two hold counts, one 3422 * for the caller and one representing the pmap and vm_page association. 3423 * 3424 * If (*isnew) is zero, the returned pv will have only one hold count. 3425 * 3426 * Since both associations can only be adjusted while the pv is locked, 3427 * together they represent just one additional hold. 3428 */ 3429 static 3430 pv_entry_t 3431 _pv_alloc(pmap_t pmap, vm_pindex_t pindex, int *isnew PMAP_DEBUG_DECL) 3432 { 3433 struct mdglobaldata *md = mdcpu; 3434 pv_entry_t pv; 3435 pv_entry_t pnew; 3436 int pmap_excl = 0; 3437 3438 pnew = NULL; 3439 if (md->gd_newpv) { 3440 #if 1 3441 pnew = atomic_swap_ptr((void *)&md->gd_newpv, NULL); 3442 #else 3443 crit_enter(); 3444 pnew = md->gd_newpv; /* might race NULL */ 3445 md->gd_newpv = NULL; 3446 crit_exit(); 3447 #endif 3448 } 3449 if (pnew == NULL) 3450 pnew = zalloc(pvzone); 3451 3452 spin_lock_shared(&pmap->pm_spin); 3453 for (;;) { 3454 /* 3455 * Shortcut cache 3456 */ 3457 pv = pv_entry_lookup(pmap, pindex); 3458 if (pv == NULL) { 3459 vm_pindex_t *pmark; 3460 3461 /* 3462 * Requires exclusive pmap spinlock 3463 */ 3464 if (pmap_excl == 0) { 3465 pmap_excl = 1; 3466 if (!spin_lock_upgrade_try(&pmap->pm_spin)) { 3467 spin_unlock_shared(&pmap->pm_spin); 3468 spin_lock(&pmap->pm_spin); 3469 continue; 3470 } 3471 } 3472 3473 /* 3474 * We need to block if someone is holding our 3475 * placemarker. As long as we determine the 3476 * placemarker has not been aquired we do not 3477 * need to get it as acquision also requires 3478 * the pmap spin lock. 3479 * 3480 * However, we can race the wakeup. 3481 */ 3482 pmark = pmap_placemarker_hash(pmap, pindex); 3483 3484 if (((*pmark ^ pindex) & ~PM_PLACEMARK_WAKEUP) == 0) { 3485 atomic_set_long(pmark, PM_PLACEMARK_WAKEUP); 3486 tsleep_interlock(pmark, 0); 3487 if (((*pmark ^ pindex) & 3488 ~PM_PLACEMARK_WAKEUP) == 0) { 3489 spin_unlock(&pmap->pm_spin); 3490 tsleep(pmark, PINTERLOCKED, "pvplc", 0); 3491 spin_lock(&pmap->pm_spin); 3492 } 3493 continue; 3494 } 3495 3496 /* 3497 * Setup the new entry 3498 */ 3499 pnew->pv_pmap = pmap; 3500 pnew->pv_pindex = pindex; 3501 pnew->pv_hold = PV_HOLD_LOCKED | 2; 3502 #ifdef PMAP_DEBUG 3503 pnew->pv_func = func; 3504 pnew->pv_line = lineno; 3505 if (pnew->pv_line_lastfree > 0) { 3506 pnew->pv_line_lastfree = 3507 -pnew->pv_line_lastfree; 3508 } 3509 #endif 3510 pv = pv_entry_rb_tree_RB_INSERT(&pmap->pm_pvroot, pnew); 3511 atomic_add_long(&pmap->pm_stats.resident_count, 1); 3512 spin_unlock(&pmap->pm_spin); 3513 *isnew = 1; 3514 3515 KKASSERT(pv == NULL); 3516 return(pnew); 3517 } 3518 3519 /* 3520 * We already have an entry, cleanup the staged pnew if 3521 * we can get the lock, otherwise block and retry. 3522 */ 3523 if (__predict_true(_pv_hold_try(pv PMAP_DEBUG_COPY))) { 3524 if (pmap_excl) 3525 spin_unlock(&pmap->pm_spin); 3526 else 3527 spin_unlock_shared(&pmap->pm_spin); 3528 #if 1 3529 pnew = atomic_swap_ptr((void *)&md->gd_newpv, pnew); 3530 if (pnew) 3531 zfree(pvzone, pnew); 3532 #else 3533 crit_enter(); 3534 if (md->gd_newpv == NULL) 3535 md->gd_newpv = pnew; 3536 else 3537 zfree(pvzone, pnew); 3538 crit_exit(); 3539 #endif 3540 KKASSERT(pv->pv_pmap == pmap && 3541 pv->pv_pindex == pindex); 3542 *isnew = 0; 3543 return(pv); 3544 } 3545 if (pmap_excl) { 3546 spin_unlock(&pmap->pm_spin); 3547 _pv_lock(pv PMAP_DEBUG_COPY); 3548 pv_put(pv); 3549 spin_lock(&pmap->pm_spin); 3550 } else { 3551 spin_unlock_shared(&pmap->pm_spin); 3552 _pv_lock(pv PMAP_DEBUG_COPY); 3553 pv_put(pv); 3554 spin_lock_shared(&pmap->pm_spin); 3555 } 3556 } 3557 /* NOT REACHED */ 3558 } 3559 3560 /* 3561 * Find the requested PV entry, returning a locked+held pv or NULL 3562 */ 3563 static 3564 pv_entry_t 3565 _pv_get(pmap_t pmap, vm_pindex_t pindex, vm_pindex_t **pmarkp PMAP_DEBUG_DECL) 3566 { 3567 pv_entry_t pv; 3568 int pmap_excl = 0; 3569 3570 spin_lock_shared(&pmap->pm_spin); 3571 for (;;) { 3572 /* 3573 * Shortcut cache 3574 */ 3575 pv = pv_entry_lookup(pmap, pindex); 3576 if (pv == NULL) { 3577 /* 3578 * Block if there is ANY placemarker. If we are to 3579 * return it, we must also aquire the spot, so we 3580 * have to block even if the placemarker is held on 3581 * a different address. 3582 * 3583 * OPTIMIZATION: If pmarkp is passed as NULL the 3584 * caller is just probing (or looking for a real 3585 * pv_entry), and in this case we only need to check 3586 * to see if the placemarker matches pindex. 3587 */ 3588 vm_pindex_t *pmark; 3589 3590 /* 3591 * Requires exclusive pmap spinlock 3592 */ 3593 if (pmap_excl == 0) { 3594 pmap_excl = 1; 3595 if (!spin_lock_upgrade_try(&pmap->pm_spin)) { 3596 spin_unlock_shared(&pmap->pm_spin); 3597 spin_lock(&pmap->pm_spin); 3598 continue; 3599 } 3600 } 3601 3602 pmark = pmap_placemarker_hash(pmap, pindex); 3603 3604 if ((pmarkp && *pmark != PM_NOPLACEMARK) || 3605 ((*pmark ^ pindex) & ~PM_PLACEMARK_WAKEUP) == 0) { 3606 atomic_set_long(pmark, PM_PLACEMARK_WAKEUP); 3607 tsleep_interlock(pmark, 0); 3608 if ((pmarkp && *pmark != PM_NOPLACEMARK) || 3609 ((*pmark ^ pindex) & 3610 ~PM_PLACEMARK_WAKEUP) == 0) { 3611 spin_unlock(&pmap->pm_spin); 3612 tsleep(pmark, PINTERLOCKED, "pvpld", 0); 3613 spin_lock(&pmap->pm_spin); 3614 } 3615 continue; 3616 } 3617 if (pmarkp) { 3618 if (atomic_swap_long(pmark, pindex) != 3619 PM_NOPLACEMARK) { 3620 panic("_pv_get: pmark race"); 3621 } 3622 *pmarkp = pmark; 3623 } 3624 spin_unlock(&pmap->pm_spin); 3625 return NULL; 3626 } 3627 if (_pv_hold_try(pv PMAP_DEBUG_COPY)) { 3628 pv_cache(pv, pindex); 3629 if (pmap_excl) 3630 spin_unlock(&pmap->pm_spin); 3631 else 3632 spin_unlock_shared(&pmap->pm_spin); 3633 KKASSERT(pv->pv_pmap == pmap && 3634 pv->pv_pindex == pindex); 3635 return(pv); 3636 } 3637 if (pmap_excl) { 3638 spin_unlock(&pmap->pm_spin); 3639 _pv_lock(pv PMAP_DEBUG_COPY); 3640 pv_put(pv); 3641 spin_lock(&pmap->pm_spin); 3642 } else { 3643 spin_unlock_shared(&pmap->pm_spin); 3644 _pv_lock(pv PMAP_DEBUG_COPY); 3645 pv_put(pv); 3646 spin_lock_shared(&pmap->pm_spin); 3647 } 3648 } 3649 } 3650 3651 /* 3652 * Lookup, hold, and attempt to lock (pmap,pindex). 3653 * 3654 * If the entry does not exist NULL is returned and *errorp is set to 0 3655 * 3656 * If the entry exists and could be successfully locked it is returned and 3657 * errorp is set to 0. 3658 * 3659 * If the entry exists but could NOT be successfully locked it is returned 3660 * held and *errorp is set to 1. 3661 * 3662 * If the entry is placemarked by someone else NULL is returned and *errorp 3663 * is set to 1. 3664 */ 3665 static 3666 pv_entry_t 3667 pv_get_try(pmap_t pmap, vm_pindex_t pindex, vm_pindex_t **pmarkp, int *errorp) 3668 { 3669 pv_entry_t pv; 3670 3671 spin_lock_shared(&pmap->pm_spin); 3672 3673 pv = pv_entry_lookup(pmap, pindex); 3674 if (pv == NULL) { 3675 vm_pindex_t *pmark; 3676 3677 pmark = pmap_placemarker_hash(pmap, pindex); 3678 3679 if (((*pmark ^ pindex) & ~PM_PLACEMARK_WAKEUP) == 0) { 3680 *errorp = 1; 3681 } else if (pmarkp && 3682 atomic_cmpset_long(pmark, PM_NOPLACEMARK, pindex)) { 3683 *errorp = 0; 3684 } else { 3685 /* 3686 * Can't set a placemark with a NULL pmarkp, or if 3687 * pmarkp is non-NULL but we failed to set our 3688 * placemark. 3689 */ 3690 *errorp = 1; 3691 } 3692 if (pmarkp) 3693 *pmarkp = pmark; 3694 spin_unlock_shared(&pmap->pm_spin); 3695 3696 return NULL; 3697 } 3698 3699 /* 3700 * XXX This has problems if the lock is shared, why? 3701 */ 3702 if (pv_hold_try(pv)) { 3703 pv_cache(pv, pindex); /* overwrite ok (shared lock) */ 3704 spin_unlock_shared(&pmap->pm_spin); 3705 *errorp = 0; 3706 KKASSERT(pv->pv_pmap == pmap && pv->pv_pindex == pindex); 3707 return(pv); /* lock succeeded */ 3708 } 3709 spin_unlock_shared(&pmap->pm_spin); 3710 *errorp = 1; 3711 3712 return (pv); /* lock failed */ 3713 } 3714 3715 /* 3716 * Lock a held pv, keeping the hold count 3717 */ 3718 static 3719 void 3720 _pv_lock(pv_entry_t pv PMAP_DEBUG_DECL) 3721 { 3722 u_int count; 3723 3724 for (;;) { 3725 count = pv->pv_hold; 3726 cpu_ccfence(); 3727 if ((count & PV_HOLD_LOCKED) == 0) { 3728 if (atomic_cmpset_int(&pv->pv_hold, count, 3729 count | PV_HOLD_LOCKED)) { 3730 #ifdef PMAP_DEBUG 3731 pv->pv_func = func; 3732 pv->pv_line = lineno; 3733 #endif 3734 return; 3735 } 3736 continue; 3737 } 3738 tsleep_interlock(pv, 0); 3739 if (atomic_cmpset_int(&pv->pv_hold, count, 3740 count | PV_HOLD_WAITING)) { 3741 #ifdef PMAP_DEBUG2 3742 if (pmap_enter_debug > 0) { 3743 --pmap_enter_debug; 3744 kprintf("pv waiting on %s:%d\n", 3745 pv->pv_func, pv->pv_line); 3746 } 3747 #endif 3748 tsleep(pv, PINTERLOCKED, "pvwait", hz); 3749 } 3750 /* retry */ 3751 } 3752 } 3753 3754 /* 3755 * Unlock a held and locked pv, keeping the hold count. 3756 */ 3757 static 3758 void 3759 pv_unlock(pv_entry_t pv) 3760 { 3761 u_int count; 3762 3763 for (;;) { 3764 count = pv->pv_hold; 3765 cpu_ccfence(); 3766 KKASSERT((count & (PV_HOLD_LOCKED | PV_HOLD_MASK)) >= 3767 (PV_HOLD_LOCKED | 1)); 3768 if (atomic_cmpset_int(&pv->pv_hold, count, 3769 count & 3770 ~(PV_HOLD_LOCKED | PV_HOLD_WAITING))) { 3771 if (count & PV_HOLD_WAITING) 3772 wakeup(pv); 3773 break; 3774 } 3775 } 3776 } 3777 3778 /* 3779 * Unlock and drop a pv. If the pv is no longer associated with a pmap 3780 * and the hold count drops to zero we will free it. 3781 * 3782 * Caller should not hold any spin locks. We are protected from hold races 3783 * by virtue of holds only occuring only with a pmap_spin or vm_page_spin 3784 * lock held. A pv cannot be located otherwise. 3785 */ 3786 static 3787 void 3788 pv_put(pv_entry_t pv) 3789 { 3790 #ifdef PMAP_DEBUG2 3791 if (pmap_enter_debug > 0) { 3792 --pmap_enter_debug; 3793 kprintf("pv_put pv=%p hold=%08x\n", pv, pv->pv_hold); 3794 } 3795 #endif 3796 3797 /* 3798 * Normal put-aways must have a pv_m associated with the pv, 3799 * but allow the case where the pv has been destructed due 3800 * to pmap_dynamic_delete. 3801 */ 3802 KKASSERT(pv->pv_pmap == NULL || pv->pv_m != NULL); 3803 3804 /* 3805 * Fast - shortcut most common condition 3806 */ 3807 if (atomic_cmpset_int(&pv->pv_hold, PV_HOLD_LOCKED | 2, 1)) 3808 return; 3809 3810 /* 3811 * Slow 3812 */ 3813 pv_unlock(pv); 3814 pv_drop(pv); 3815 } 3816 3817 /* 3818 * Remove the pmap association from a pv, require that pv_m already be removed, 3819 * then unlock and drop the pv. Any pte operations must have already been 3820 * completed. This call may result in a last-drop which will physically free 3821 * the pv. 3822 * 3823 * Removing the pmap association entails an additional drop. 3824 * 3825 * pv must be exclusively locked on call and will be disposed of on return. 3826 */ 3827 static 3828 void 3829 _pv_free(pv_entry_t pv, pv_entry_t pvp PMAP_DEBUG_DECL) 3830 { 3831 pmap_t pmap; 3832 3833 #ifdef PMAP_DEBUG 3834 pv->pv_func_lastfree = func; 3835 pv->pv_line_lastfree = lineno; 3836 #endif 3837 KKASSERT(pv->pv_m == NULL); 3838 KKASSERT((pv->pv_hold & (PV_HOLD_LOCKED|PV_HOLD_MASK)) >= 3839 (PV_HOLD_LOCKED|1)); 3840 if ((pmap = pv->pv_pmap) != NULL) { 3841 spin_lock(&pmap->pm_spin); 3842 KKASSERT(pv->pv_pmap == pmap); 3843 if (pmap->pm_pvhint_pt == pv) 3844 pmap->pm_pvhint_pt = NULL; 3845 if (pmap->pm_pvhint_pte == pv) 3846 pmap->pm_pvhint_pte = NULL; 3847 pv_entry_rb_tree_RB_REMOVE(&pmap->pm_pvroot, pv); 3848 atomic_add_long(&pmap->pm_stats.resident_count, -1); 3849 pv->pv_pmap = NULL; 3850 pv->pv_pindex = 0; 3851 spin_unlock(&pmap->pm_spin); 3852 3853 /* 3854 * Try to shortcut three atomic ops, otherwise fall through 3855 * and do it normally. Drop two refs and the lock all in 3856 * one go. 3857 */ 3858 if (pvp) 3859 vm_page_unwire_quick(pvp->pv_m); 3860 if (atomic_cmpset_int(&pv->pv_hold, PV_HOLD_LOCKED | 2, 0)) { 3861 #ifdef PMAP_DEBUG2 3862 if (pmap_enter_debug > 0) { 3863 --pmap_enter_debug; 3864 kprintf("pv_free: free pv %p\n", pv); 3865 } 3866 #endif 3867 zfree(pvzone, pv); 3868 return; 3869 } 3870 pv_drop(pv); /* ref for pv_pmap */ 3871 } 3872 pv_unlock(pv); 3873 pv_drop(pv); 3874 } 3875 3876 /* 3877 * This routine is very drastic, but can save the system 3878 * in a pinch. 3879 */ 3880 void 3881 pmap_collect(void) 3882 { 3883 int i; 3884 vm_page_t m; 3885 static int warningdone=0; 3886 3887 if (pmap_pagedaemon_waken == 0) 3888 return; 3889 pmap_pagedaemon_waken = 0; 3890 if (warningdone < 5) { 3891 kprintf("pmap_collect: collecting pv entries -- " 3892 "suggest increasing PMAP_SHPGPERPROC\n"); 3893 warningdone++; 3894 } 3895 3896 for (i = 0; i < vm_page_array_size; i++) { 3897 m = &vm_page_array[i]; 3898 if (m->wire_count || m->hold_count) 3899 continue; 3900 if (vm_page_busy_try(m, TRUE) == 0) { 3901 if (m->wire_count == 0 && m->hold_count == 0) { 3902 pmap_remove_all(m); 3903 } 3904 vm_page_wakeup(m); 3905 } 3906 } 3907 } 3908 3909 /* 3910 * Scan the pmap for active page table entries and issue a callback. 3911 * The callback must dispose of pte_pv, whos PTE entry is at *ptep in 3912 * its parent page table. 3913 * 3914 * pte_pv will be NULL if the page or page table is unmanaged. 3915 * pt_pv will point to the page table page containing the pte for the page. 3916 * 3917 * NOTE! If we come across an unmanaged page TABLE (verses an unmanaged page), 3918 * we pass a NULL pte_pv and we pass a pt_pv pointing to the passed 3919 * process pmap's PD and page to the callback function. This can be 3920 * confusing because the pt_pv is really a pd_pv, and the target page 3921 * table page is simply aliased by the pmap and not owned by it. 3922 * 3923 * It is assumed that the start and end are properly rounded to the page size. 3924 * 3925 * It is assumed that PD pages and above are managed and thus in the RB tree, 3926 * allowing us to use RB_SCAN from the PD pages down for ranged scans. 3927 */ 3928 struct pmap_scan_info { 3929 struct pmap *pmap; 3930 vm_offset_t sva; 3931 vm_offset_t eva; 3932 vm_pindex_t sva_pd_pindex; 3933 vm_pindex_t eva_pd_pindex; 3934 void (*func)(pmap_t, struct pmap_scan_info *, 3935 pv_entry_t, vm_pindex_t *, pv_entry_t, 3936 int, vm_offset_t, 3937 pt_entry_t *, void *); 3938 void *arg; 3939 pmap_inval_bulk_t bulk_core; 3940 pmap_inval_bulk_t *bulk; 3941 int count; 3942 int stop; 3943 }; 3944 3945 static int pmap_scan_cmp(pv_entry_t pv, void *data); 3946 static int pmap_scan_callback(pv_entry_t pv, void *data); 3947 3948 static void 3949 pmap_scan(struct pmap_scan_info *info, int smp_inval) 3950 { 3951 struct pmap *pmap = info->pmap; 3952 pv_entry_t pd_pv; /* A page directory PV */ 3953 pv_entry_t pt_pv; /* A page table PV */ 3954 pv_entry_t pte_pv; /* A page table entry PV */ 3955 vm_pindex_t *pte_placemark; 3956 vm_pindex_t *pt_placemark; 3957 pt_entry_t *ptep; 3958 pt_entry_t oldpte; 3959 struct pv_entry dummy_pv; 3960 3961 info->stop = 0; 3962 if (pmap == NULL) 3963 return; 3964 if (info->sva == info->eva) 3965 return; 3966 if (smp_inval) { 3967 info->bulk = &info->bulk_core; 3968 pmap_inval_bulk_init(&info->bulk_core, pmap); 3969 } else { 3970 info->bulk = NULL; 3971 } 3972 3973 /* 3974 * Hold the token for stability; if the pmap is empty we have nothing 3975 * to do. 3976 */ 3977 #if 0 3978 if (pmap->pm_stats.resident_count == 0) { 3979 return; 3980 } 3981 #endif 3982 3983 info->count = 0; 3984 3985 /* 3986 * Special handling for scanning one page, which is a very common 3987 * operation (it is?). 3988 * 3989 * NOTE: Locks must be ordered bottom-up. pte,pt,pd,pdp,pml4 3990 */ 3991 if (info->sva + PAGE_SIZE == info->eva) { 3992 if (info->sva >= VM_MAX_USER_ADDRESS) { 3993 /* 3994 * Kernel mappings do not track wire counts on 3995 * page table pages and only maintain pd_pv and 3996 * pte_pv levels so pmap_scan() works. 3997 */ 3998 pt_pv = NULL; 3999 pte_pv = pv_get(pmap, pmap_pte_pindex(info->sva), 4000 &pte_placemark); 4001 ptep = vtopte(info->sva); 4002 } else { 4003 /* 4004 * User pages which are unmanaged will not have a 4005 * pte_pv. User page table pages which are unmanaged 4006 * (shared from elsewhere) will also not have a pt_pv. 4007 * The func() callback will pass both pte_pv and pt_pv 4008 * as NULL in that case. 4009 * 4010 * We hold pte_placemark across the operation for 4011 * unmanaged pages. 4012 * 4013 * WARNING! We must hold pt_placemark across the 4014 * *ptep test to prevent misintepreting 4015 * a non-zero *ptep as a shared page 4016 * table page. Hold it across the function 4017 * callback as well for SMP safety. 4018 */ 4019 pte_pv = pv_get(pmap, pmap_pte_pindex(info->sva), 4020 &pte_placemark); 4021 pt_pv = pv_get(pmap, pmap_pt_pindex(info->sva), 4022 &pt_placemark); 4023 if (pt_pv == NULL) { 4024 KKASSERT(pte_pv == NULL); 4025 pd_pv = pv_get(pmap, 4026 pmap_pd_pindex(info->sva), 4027 NULL); 4028 if (pd_pv) { 4029 ptep = pv_pte_lookup(pd_pv, 4030 pmap_pt_index(info->sva)); 4031 if (*ptep) { 4032 info->func(pmap, info, 4033 NULL, pt_placemark, 4034 pd_pv, 1, 4035 info->sva, ptep, 4036 info->arg); 4037 } else { 4038 pv_placemarker_wakeup(pmap, 4039 pt_placemark); 4040 } 4041 pv_put(pd_pv); 4042 } else { 4043 pv_placemarker_wakeup(pmap, 4044 pt_placemark); 4045 } 4046 pv_placemarker_wakeup(pmap, pte_placemark); 4047 goto fast_skip; 4048 } 4049 ptep = pv_pte_lookup(pt_pv, pmap_pte_index(info->sva)); 4050 } 4051 4052 /* 4053 * NOTE: *ptep can't be ripped out from under us if we hold 4054 * pte_pv (or pte_placemark) locked, but bits can 4055 * change. 4056 */ 4057 oldpte = *ptep; 4058 cpu_ccfence(); 4059 if (oldpte == 0) { 4060 KKASSERT(pte_pv == NULL); 4061 pv_placemarker_wakeup(pmap, pte_placemark); 4062 } else if (pte_pv) { 4063 KASSERT((oldpte & (pmap->pmap_bits[PG_MANAGED_IDX] | 4064 pmap->pmap_bits[PG_V_IDX])) == 4065 (pmap->pmap_bits[PG_MANAGED_IDX] | 4066 pmap->pmap_bits[PG_V_IDX]), 4067 ("badA *ptep %016lx/%016lx sva %016lx pte_pv %p", 4068 *ptep, oldpte, info->sva, pte_pv)); 4069 info->func(pmap, info, pte_pv, NULL, pt_pv, 0, 4070 info->sva, ptep, info->arg); 4071 } else { 4072 KASSERT((oldpte & (pmap->pmap_bits[PG_MANAGED_IDX] | 4073 pmap->pmap_bits[PG_V_IDX])) == 4074 pmap->pmap_bits[PG_V_IDX], 4075 ("badB *ptep %016lx/%016lx sva %016lx pte_pv NULL", 4076 *ptep, oldpte, info->sva)); 4077 info->func(pmap, info, NULL, pte_placemark, pt_pv, 0, 4078 info->sva, ptep, info->arg); 4079 } 4080 if (pt_pv) 4081 pv_put(pt_pv); 4082 fast_skip: 4083 pmap_inval_bulk_flush(info->bulk); 4084 return; 4085 } 4086 4087 /* 4088 * Nominal scan case, RB_SCAN() for PD pages and iterate from 4089 * there. 4090 * 4091 * WARNING! eva can overflow our standard ((N + mask) >> bits) 4092 * bounds, resulting in a pd_pindex of 0. To solve the 4093 * problem we use an inclusive range. 4094 */ 4095 info->sva_pd_pindex = pmap_pd_pindex(info->sva); 4096 info->eva_pd_pindex = pmap_pd_pindex(info->eva - PAGE_SIZE); 4097 4098 if (info->sva >= VM_MAX_USER_ADDRESS) { 4099 /* 4100 * The kernel does not currently maintain any pv_entry's for 4101 * higher-level page tables. 4102 */ 4103 bzero(&dummy_pv, sizeof(dummy_pv)); 4104 dummy_pv.pv_pindex = info->sva_pd_pindex; 4105 spin_lock(&pmap->pm_spin); 4106 while (dummy_pv.pv_pindex <= info->eva_pd_pindex) { 4107 pmap_scan_callback(&dummy_pv, info); 4108 ++dummy_pv.pv_pindex; 4109 if (dummy_pv.pv_pindex < info->sva_pd_pindex) /*wrap*/ 4110 break; 4111 } 4112 spin_unlock(&pmap->pm_spin); 4113 } else { 4114 /* 4115 * User page tables maintain local PML4, PDP, and PD 4116 * pv_entry's at the very least. PT pv's might be 4117 * unmanaged and thus not exist. PTE pv's might be 4118 * unmanaged and thus not exist. 4119 */ 4120 spin_lock(&pmap->pm_spin); 4121 pv_entry_rb_tree_RB_SCAN(&pmap->pm_pvroot, pmap_scan_cmp, 4122 pmap_scan_callback, info); 4123 spin_unlock(&pmap->pm_spin); 4124 } 4125 pmap_inval_bulk_flush(info->bulk); 4126 } 4127 4128 /* 4129 * WARNING! pmap->pm_spin held 4130 * 4131 * WARNING! eva can overflow our standard ((N + mask) >> bits) 4132 * bounds, resulting in a pd_pindex of 0. To solve the 4133 * problem we use an inclusive range. 4134 */ 4135 static int 4136 pmap_scan_cmp(pv_entry_t pv, void *data) 4137 { 4138 struct pmap_scan_info *info = data; 4139 if (pv->pv_pindex < info->sva_pd_pindex) 4140 return(-1); 4141 if (pv->pv_pindex > info->eva_pd_pindex) 4142 return(1); 4143 return(0); 4144 } 4145 4146 /* 4147 * pmap_scan() by PDs 4148 * 4149 * WARNING! pmap->pm_spin held 4150 */ 4151 static int 4152 pmap_scan_callback(pv_entry_t pv, void *data) 4153 { 4154 struct pmap_scan_info *info = data; 4155 struct pmap *pmap = info->pmap; 4156 pv_entry_t pd_pv; /* A page directory PV */ 4157 pv_entry_t pt_pv; /* A page table PV */ 4158 vm_pindex_t *pt_placemark; 4159 pt_entry_t *ptep; 4160 pt_entry_t oldpte; 4161 vm_offset_t sva; 4162 vm_offset_t eva; 4163 vm_offset_t va_next; 4164 vm_pindex_t pd_pindex; 4165 int error; 4166 4167 /* 4168 * Stop if requested 4169 */ 4170 if (info->stop) 4171 return -1; 4172 4173 /* 4174 * Pull the PD pindex from the pv before releasing the spinlock. 4175 * 4176 * WARNING: pv is faked for kernel pmap scans. 4177 */ 4178 pd_pindex = pv->pv_pindex; 4179 spin_unlock(&pmap->pm_spin); 4180 pv = NULL; /* invalid after spinlock unlocked */ 4181 4182 /* 4183 * Calculate the page range within the PD. SIMPLE pmaps are 4184 * direct-mapped for the entire 2^64 address space. Normal pmaps 4185 * reflect the user and kernel address space which requires 4186 * cannonicalization w/regards to converting pd_pindex's back 4187 * into addresses. 4188 */ 4189 sva = (pd_pindex - pmap_pd_pindex(0)) << PDPSHIFT; 4190 if ((pmap->pm_flags & PMAP_FLAG_SIMPLE) == 0 && 4191 (sva & PML4_SIGNMASK)) { 4192 sva |= PML4_SIGNMASK; 4193 } 4194 eva = sva + NBPDP; /* can overflow */ 4195 if (sva < info->sva) 4196 sva = info->sva; 4197 if (eva < info->sva || eva > info->eva) 4198 eva = info->eva; 4199 4200 /* 4201 * NOTE: kernel mappings do not track page table pages, only 4202 * terminal pages. 4203 * 4204 * NOTE: Locks must be ordered bottom-up. pte,pt,pd,pdp,pml4. 4205 * However, for the scan to be efficient we try to 4206 * cache items top-down. 4207 */ 4208 pd_pv = NULL; 4209 pt_pv = NULL; 4210 4211 for (; sva < eva; sva = va_next) { 4212 if (info->stop) 4213 break; 4214 if (sva >= VM_MAX_USER_ADDRESS) { 4215 if (pt_pv) { 4216 pv_put(pt_pv); 4217 pt_pv = NULL; 4218 } 4219 goto kernel_skip; 4220 } 4221 4222 /* 4223 * PD cache, scan shortcut if it doesn't exist. 4224 */ 4225 if (pd_pv == NULL) { 4226 pd_pv = pv_get(pmap, pmap_pd_pindex(sva), NULL); 4227 } else if (pd_pv->pv_pmap != pmap || 4228 pd_pv->pv_pindex != pmap_pd_pindex(sva)) { 4229 pv_put(pd_pv); 4230 pd_pv = pv_get(pmap, pmap_pd_pindex(sva), NULL); 4231 } 4232 if (pd_pv == NULL) { 4233 va_next = (sva + NBPDP) & ~PDPMASK; 4234 if (va_next < sva) 4235 va_next = eva; 4236 continue; 4237 } 4238 4239 /* 4240 * PT cache 4241 * 4242 * NOTE: The cached pt_pv can be removed from the pmap when 4243 * pmap_dynamic_delete is enabled. 4244 */ 4245 if (pt_pv && (pt_pv->pv_pmap != pmap || 4246 pt_pv->pv_pindex != pmap_pt_pindex(sva))) { 4247 pv_put(pt_pv); 4248 pt_pv = NULL; 4249 } 4250 if (pt_pv == NULL) { 4251 pt_pv = pv_get_try(pmap, pmap_pt_pindex(sva), 4252 &pt_placemark, &error); 4253 if (error) { 4254 pv_put(pd_pv); /* lock order */ 4255 pd_pv = NULL; 4256 if (pt_pv) { 4257 pv_lock(pt_pv); 4258 pv_put(pt_pv); 4259 pt_pv = NULL; 4260 } else { 4261 pv_placemarker_wait(pmap, pt_placemark); 4262 } 4263 va_next = sva; 4264 continue; 4265 } 4266 /* may have to re-check later if pt_pv is NULL here */ 4267 } 4268 4269 /* 4270 * If pt_pv is NULL we either have an shared page table 4271 * page and must issue a callback specific to that case, 4272 * or there is no page table page. 4273 * 4274 * Either way we can skip the page table page. 4275 * 4276 * WARNING! pt_pv can also be NULL due to a pv creation 4277 * race where we find it to be NULL and then 4278 * later see a pte_pv. But its possible the pt_pv 4279 * got created inbetween the two operations, so 4280 * we must check. 4281 */ 4282 if (pt_pv == NULL) { 4283 /* 4284 * Possible unmanaged (shared from another pmap) 4285 * page table page. 4286 * 4287 * WARNING! We must hold pt_placemark across the 4288 * *ptep test to prevent misintepreting 4289 * a non-zero *ptep as a shared page 4290 * table page. Hold it across the function 4291 * callback as well for SMP safety. 4292 */ 4293 ptep = pv_pte_lookup(pd_pv, pmap_pt_index(sva)); 4294 if (*ptep & pmap->pmap_bits[PG_V_IDX]) { 4295 info->func(pmap, info, NULL, pt_placemark, 4296 pd_pv, 1, 4297 sva, ptep, info->arg); 4298 } else { 4299 pv_placemarker_wakeup(pmap, pt_placemark); 4300 } 4301 4302 /* 4303 * Done, move to next page table page. 4304 */ 4305 va_next = (sva + NBPDR) & ~PDRMASK; 4306 if (va_next < sva) 4307 va_next = eva; 4308 continue; 4309 } 4310 4311 /* 4312 * From this point in the loop testing pt_pv for non-NULL 4313 * means we are in UVM, else if it is NULL we are in KVM. 4314 * 4315 * Limit our scan to either the end of the va represented 4316 * by the current page table page, or to the end of the 4317 * range being removed. 4318 */ 4319 kernel_skip: 4320 va_next = (sva + NBPDR) & ~PDRMASK; 4321 if (va_next < sva) 4322 va_next = eva; 4323 if (va_next > eva) 4324 va_next = eva; 4325 4326 /* 4327 * Scan the page table for pages. Some pages may not be 4328 * managed (might not have a pv_entry). 4329 * 4330 * There is no page table management for kernel pages so 4331 * pt_pv will be NULL in that case, but otherwise pt_pv 4332 * is non-NULL, locked, and referenced. 4333 */ 4334 4335 /* 4336 * At this point a non-NULL pt_pv means a UVA, and a NULL 4337 * pt_pv means a KVA. 4338 */ 4339 if (pt_pv) 4340 ptep = pv_pte_lookup(pt_pv, pmap_pte_index(sva)); 4341 else 4342 ptep = vtopte(sva); 4343 4344 while (sva < va_next) { 4345 pv_entry_t pte_pv; 4346 vm_pindex_t *pte_placemark; 4347 4348 /* 4349 * Yield every 64 pages, stop if requested. 4350 */ 4351 if ((++info->count & 63) == 0) 4352 lwkt_user_yield(); 4353 if (info->stop) 4354 break; 4355 4356 /* 4357 * We can shortcut our scan if *ptep == 0. This is 4358 * an unlocked check. 4359 */ 4360 if (*ptep == 0) { 4361 sva += PAGE_SIZE; 4362 ++ptep; 4363 continue; 4364 } 4365 cpu_ccfence(); 4366 4367 /* 4368 * Acquire the related pte_pv, if any. If *ptep == 0 4369 * the related pte_pv should not exist, but if *ptep 4370 * is not zero the pte_pv may or may not exist (e.g. 4371 * will not exist for an unmanaged page). 4372 * 4373 * However a multitude of races are possible here 4374 * so if we cannot lock definite state we clean out 4375 * our cache and break the inner while() loop to 4376 * force a loop up to the top of the for(). 4377 * 4378 * XXX unlock/relock pd_pv, pt_pv, and re-test their 4379 * validity instead of looping up? 4380 */ 4381 pte_pv = pv_get_try(pmap, pmap_pte_pindex(sva), 4382 &pte_placemark, &error); 4383 if (error) { 4384 pv_put(pd_pv); /* lock order */ 4385 pd_pv = NULL; 4386 if (pt_pv) { 4387 pv_put(pt_pv); /* lock order */ 4388 pt_pv = NULL; 4389 } 4390 if (pte_pv) { /* block */ 4391 pv_lock(pte_pv); 4392 pv_put(pte_pv); 4393 pte_pv = NULL; 4394 } else { 4395 pv_placemarker_wait(pmap, 4396 pte_placemark); 4397 } 4398 va_next = sva; /* retry */ 4399 break; 4400 } 4401 4402 /* 4403 * Reload *ptep after successfully locking the 4404 * pindex. If *ptep == 0 we had better NOT have a 4405 * pte_pv. 4406 */ 4407 cpu_ccfence(); 4408 oldpte = *ptep; 4409 if (oldpte == 0) { 4410 if (pte_pv) { 4411 kprintf("Unexpected non-NULL pte_pv " 4412 "%p pt_pv %p " 4413 "*ptep = %016lx/%016lx\n", 4414 pte_pv, pt_pv, *ptep, oldpte); 4415 panic("Unexpected non-NULL pte_pv"); 4416 } else { 4417 pv_placemarker_wakeup(pmap, pte_placemark); 4418 } 4419 sva += PAGE_SIZE; 4420 ++ptep; 4421 continue; 4422 } 4423 4424 /* 4425 * We can't hold pd_pv across the callback (because 4426 * we don't pass it to the callback and the callback 4427 * might deadlock) 4428 */ 4429 if (pd_pv) { 4430 vm_page_wire_quick(pd_pv->pv_m); 4431 pv_unlock(pd_pv); 4432 } 4433 4434 /* 4435 * Ready for the callback. The locked pte_pv (if any) 4436 * is consumed by the callback. pte_pv will exist if 4437 * the page is managed, and will not exist if it 4438 * isn't. 4439 */ 4440 if (oldpte & pmap->pmap_bits[PG_MANAGED_IDX]) { 4441 /* 4442 * Managed pte 4443 */ 4444 KASSERT(pte_pv && 4445 (oldpte & pmap->pmap_bits[PG_V_IDX]), 4446 ("badC *ptep %016lx/%016lx sva %016lx " 4447 "pte_pv %p", 4448 *ptep, oldpte, sva, pte_pv)); 4449 /* 4450 * We must unlock pd_pv across the callback 4451 * to avoid deadlocks on any recursive 4452 * disposal. Re-check that it still exists 4453 * after re-locking. 4454 * 4455 * Call target disposes of pte_pv and may 4456 * destroy but will not dispose of pt_pv. 4457 */ 4458 info->func(pmap, info, pte_pv, NULL, 4459 pt_pv, 0, 4460 sva, ptep, info->arg); 4461 } else { 4462 /* 4463 * Unmanaged pte 4464 * 4465 * We must unlock pd_pv across the callback 4466 * to avoid deadlocks on any recursive 4467 * disposal. Re-check that it still exists 4468 * after re-locking. 4469 * 4470 * Call target disposes of pte_pv or 4471 * pte_placemark and may destroy but will 4472 * not dispose of pt_pv. 4473 */ 4474 KASSERT(pte_pv == NULL && 4475 (oldpte & pmap->pmap_bits[PG_V_IDX]), 4476 ("badD *ptep %016lx/%016lx sva %016lx " 4477 "pte_pv %p pte_pv->pv_m %p ", 4478 *ptep, oldpte, sva, 4479 pte_pv, (pte_pv ? pte_pv->pv_m : NULL))); 4480 if (pte_pv) 4481 kprintf("RaceD\n"); 4482 if (pte_pv) { 4483 info->func(pmap, info, 4484 pte_pv, NULL, 4485 pt_pv, 0, 4486 sva, ptep, info->arg); 4487 } else { 4488 info->func(pmap, info, 4489 NULL, pte_placemark, 4490 pt_pv, 0, 4491 sva, ptep, info->arg); 4492 } 4493 } 4494 if (pd_pv) { 4495 pv_lock(pd_pv); 4496 vm_page_unwire_quick(pd_pv->pv_m); 4497 if (pd_pv->pv_pmap == NULL) { 4498 va_next = sva; /* retry */ 4499 break; 4500 } 4501 } 4502 4503 /* 4504 * NOTE: The cached pt_pv can be removed from the 4505 * pmap when pmap_dynamic_delete is enabled, 4506 * which will cause ptep to become stale. 4507 * 4508 * This also means that no pages remain under 4509 * the PT, so we can just break out of the inner 4510 * loop and let the outer loop clean everything 4511 * up. 4512 */ 4513 if (pt_pv && pt_pv->pv_pmap != pmap) 4514 break; 4515 pte_pv = NULL; 4516 sva += PAGE_SIZE; 4517 ++ptep; 4518 } 4519 } 4520 if (pd_pv) { 4521 pv_put(pd_pv); 4522 pd_pv = NULL; 4523 } 4524 if (pt_pv) { 4525 pv_put(pt_pv); 4526 pt_pv = NULL; 4527 } 4528 if ((++info->count & 7) == 0) 4529 lwkt_user_yield(); 4530 4531 /* 4532 * Relock before returning. 4533 */ 4534 spin_lock(&pmap->pm_spin); 4535 return (0); 4536 } 4537 4538 void 4539 pmap_remove(struct pmap *pmap, vm_offset_t sva, vm_offset_t eva) 4540 { 4541 struct pmap_scan_info info; 4542 4543 info.pmap = pmap; 4544 info.sva = sva; 4545 info.eva = eva; 4546 info.func = pmap_remove_callback; 4547 info.arg = NULL; 4548 pmap_scan(&info, 1); 4549 #if 0 4550 cpu_invltlb(); 4551 if (eva - sva < 1024*1024) { 4552 while (sva < eva) { 4553 cpu_invlpg((void *)sva); 4554 sva += PAGE_SIZE; 4555 } 4556 } 4557 #endif 4558 } 4559 4560 static void 4561 pmap_remove_noinval(struct pmap *pmap, vm_offset_t sva, vm_offset_t eva) 4562 { 4563 struct pmap_scan_info info; 4564 4565 info.pmap = pmap; 4566 info.sva = sva; 4567 info.eva = eva; 4568 info.func = pmap_remove_callback; 4569 info.arg = NULL; 4570 pmap_scan(&info, 0); 4571 } 4572 4573 static void 4574 pmap_remove_callback(pmap_t pmap, struct pmap_scan_info *info, 4575 pv_entry_t pte_pv, vm_pindex_t *pte_placemark, 4576 pv_entry_t pt_pv, int sharept, 4577 vm_offset_t va, pt_entry_t *ptep, void *arg __unused) 4578 { 4579 pt_entry_t pte; 4580 4581 if (pte_pv) { 4582 /* 4583 * Managed entry 4584 * 4585 * This will also drop pt_pv's wire_count. Note that 4586 * terminal pages are not wired based on mmu presence. 4587 * 4588 * NOTE: If this is the kernel_pmap, pt_pv can be NULL. 4589 */ 4590 KKASSERT(pte_pv->pv_m != NULL); 4591 pmap_remove_pv_pte(pte_pv, pt_pv, info->bulk, 2); 4592 pte_pv = NULL; /* safety */ 4593 4594 /* 4595 * Recursively destroy higher-level page tables. 4596 * 4597 * This is optional. If we do not, they will still 4598 * be destroyed when the process exits. 4599 * 4600 * NOTE: Do not destroy pv_entry's with extra hold refs, 4601 * a caller may have unlocked it and intends to 4602 * continue to use it. 4603 */ 4604 if (pmap_dynamic_delete && 4605 pt_pv && 4606 pt_pv->pv_m && 4607 pt_pv->pv_m->wire_count == 1 && 4608 (pt_pv->pv_hold & PV_HOLD_MASK) == 2 && 4609 pt_pv->pv_pindex != pmap_pml4_pindex()) { 4610 if (pmap_dynamic_delete == 2) 4611 kprintf("B %jd %08x\n", pt_pv->pv_pindex, pt_pv->pv_hold); 4612 pv_hold(pt_pv); /* extra hold */ 4613 pmap_remove_pv_pte(pt_pv, NULL, info->bulk, 1); 4614 pv_lock(pt_pv); /* prior extra hold + relock */ 4615 } 4616 } else if (sharept == 0) { 4617 /* 4618 * Unmanaged pte (pte_placemark is non-NULL) 4619 * 4620 * pt_pv's wire_count is still bumped by unmanaged pages 4621 * so we must decrement it manually. 4622 * 4623 * We have to unwire the target page table page. 4624 */ 4625 pte = pmap_inval_bulk(info->bulk, va, ptep, 0); 4626 if (pte & pmap->pmap_bits[PG_W_IDX]) 4627 atomic_add_long(&pmap->pm_stats.wired_count, -1); 4628 atomic_add_long(&pmap->pm_stats.resident_count, -1); 4629 if (vm_page_unwire_quick(pt_pv->pv_m)) 4630 panic("pmap_remove: insufficient wirecount"); 4631 pv_placemarker_wakeup(pmap, pte_placemark); 4632 } else { 4633 /* 4634 * Unmanaged page table (pt, pd, or pdp. Not pte) for 4635 * a shared page table. 4636 * 4637 * pt_pv is actually the pd_pv for our pmap (not the shared 4638 * object pmap). 4639 * 4640 * We have to unwire the target page table page and we 4641 * have to unwire our page directory page. 4642 * 4643 * It is unclear how we can invalidate a segment so we 4644 * invalidate -1 which invlidates the tlb. 4645 */ 4646 pte = pmap_inval_bulk(info->bulk, (vm_offset_t)-1, ptep, 0); 4647 atomic_add_long(&pmap->pm_stats.resident_count, -1); 4648 KKASSERT((pte & pmap->pmap_bits[PG_DEVICE_IDX]) == 0); 4649 if (vm_page_unwire_quick(PHYS_TO_VM_PAGE(pte & PG_FRAME))) 4650 panic("pmap_remove: shared pgtable1 bad wirecount"); 4651 if (vm_page_unwire_quick(pt_pv->pv_m)) 4652 panic("pmap_remove: shared pgtable2 bad wirecount"); 4653 pv_placemarker_wakeup(pmap, pte_placemark); 4654 } 4655 } 4656 4657 /* 4658 * Removes this physical page from all physical maps in which it resides. 4659 * Reflects back modify bits to the pager. 4660 * 4661 * This routine may not be called from an interrupt. 4662 */ 4663 static 4664 void 4665 pmap_remove_all(vm_page_t m) 4666 { 4667 pv_entry_t pv; 4668 pmap_inval_bulk_t bulk; 4669 4670 if (!pmap_initialized /* || (m->flags & PG_FICTITIOUS)*/) 4671 return; 4672 4673 vm_page_spin_lock(m); 4674 while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) { 4675 KKASSERT(pv->pv_m == m); 4676 if (pv_hold_try(pv)) { 4677 vm_page_spin_unlock(m); 4678 } else { 4679 vm_page_spin_unlock(m); 4680 pv_lock(pv); 4681 pv_put(pv); 4682 vm_page_spin_lock(m); 4683 continue; 4684 } 4685 KKASSERT(pv->pv_pmap && pv->pv_m == m); 4686 4687 /* 4688 * Holding no spinlocks, pv is locked. Once we scrap 4689 * pv we can no longer use it as a list iterator (but 4690 * we are doing a TAILQ_FIRST() so we are ok). 4691 */ 4692 pmap_inval_bulk_init(&bulk, pv->pv_pmap); 4693 pmap_remove_pv_pte(pv, NULL, &bulk, 2); 4694 pv = NULL; /* safety */ 4695 pmap_inval_bulk_flush(&bulk); 4696 vm_page_spin_lock(m); 4697 } 4698 KKASSERT((m->flags & (PG_MAPPED|PG_WRITEABLE)) == 0); 4699 vm_page_spin_unlock(m); 4700 } 4701 4702 /* 4703 * Removes the page from a particular pmap 4704 */ 4705 void 4706 pmap_remove_specific(pmap_t pmap, vm_page_t m) 4707 { 4708 pv_entry_t pv; 4709 pmap_inval_bulk_t bulk; 4710 4711 if (!pmap_initialized) 4712 return; 4713 4714 again: 4715 vm_page_spin_lock(m); 4716 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 4717 if (pv->pv_pmap != pmap) 4718 continue; 4719 KKASSERT(pv->pv_m == m); 4720 if (pv_hold_try(pv)) { 4721 vm_page_spin_unlock(m); 4722 } else { 4723 vm_page_spin_unlock(m); 4724 pv_lock(pv); 4725 pv_put(pv); 4726 goto again; 4727 } 4728 KKASSERT(pv->pv_pmap == pmap && pv->pv_m == m); 4729 4730 /* 4731 * Holding no spinlocks, pv is locked. Once gone it can't 4732 * be used as an iterator. In fact, because we couldn't 4733 * necessarily lock it atomically it may have moved within 4734 * the list and ALSO cannot be used as an iterator. 4735 */ 4736 pmap_inval_bulk_init(&bulk, pv->pv_pmap); 4737 pmap_remove_pv_pte(pv, NULL, &bulk, 2); 4738 pv = NULL; /* safety */ 4739 pmap_inval_bulk_flush(&bulk); 4740 goto again; 4741 } 4742 vm_page_spin_unlock(m); 4743 } 4744 4745 /* 4746 * Set the physical protection on the specified range of this map 4747 * as requested. This function is typically only used for debug watchpoints 4748 * and COW pages. 4749 * 4750 * This function may not be called from an interrupt if the map is 4751 * not the kernel_pmap. 4752 * 4753 * NOTE! For shared page table pages we just unmap the page. 4754 */ 4755 void 4756 pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot) 4757 { 4758 struct pmap_scan_info info; 4759 /* JG review for NX */ 4760 4761 if (pmap == NULL) 4762 return; 4763 if ((prot & (VM_PROT_READ | VM_PROT_EXECUTE)) == VM_PROT_NONE) { 4764 pmap_remove(pmap, sva, eva); 4765 return; 4766 } 4767 if (prot & VM_PROT_WRITE) 4768 return; 4769 info.pmap = pmap; 4770 info.sva = sva; 4771 info.eva = eva; 4772 info.func = pmap_protect_callback; 4773 info.arg = &prot; 4774 pmap_scan(&info, 1); 4775 } 4776 4777 static 4778 void 4779 pmap_protect_callback(pmap_t pmap, struct pmap_scan_info *info, 4780 pv_entry_t pte_pv, vm_pindex_t *pte_placemark, 4781 pv_entry_t pt_pv, int sharept, 4782 vm_offset_t va, pt_entry_t *ptep, void *arg __unused) 4783 { 4784 pt_entry_t pbits; 4785 pt_entry_t cbits; 4786 pt_entry_t pte; 4787 vm_page_t m; 4788 4789 again: 4790 pbits = *ptep; 4791 cbits = pbits; 4792 if (pte_pv) { 4793 KKASSERT(pte_pv->pv_m != NULL); 4794 m = NULL; 4795 if (pbits & pmap->pmap_bits[PG_A_IDX]) { 4796 if ((pbits & pmap->pmap_bits[PG_DEVICE_IDX]) == 0) { 4797 m = PHYS_TO_VM_PAGE(pbits & PG_FRAME); 4798 KKASSERT(m == pte_pv->pv_m); 4799 vm_page_flag_set(m, PG_REFERENCED); 4800 } 4801 cbits &= ~pmap->pmap_bits[PG_A_IDX]; 4802 } 4803 if (pbits & pmap->pmap_bits[PG_M_IDX]) { 4804 if (pmap_track_modified(pte_pv->pv_pindex)) { 4805 if ((pbits & pmap->pmap_bits[PG_DEVICE_IDX]) == 0) { 4806 if (m == NULL) { 4807 m = PHYS_TO_VM_PAGE(pbits & 4808 PG_FRAME); 4809 } 4810 vm_page_dirty(m); 4811 } 4812 cbits &= ~pmap->pmap_bits[PG_M_IDX]; 4813 } 4814 } 4815 } else if (sharept) { 4816 /* 4817 * Unmanaged page table, pt_pv is actually the pd_pv 4818 * for our pmap (not the object's shared pmap). 4819 * 4820 * When asked to protect something in a shared page table 4821 * page we just unmap the page table page. We have to 4822 * invalidate the tlb in this situation. 4823 * 4824 * XXX Warning, shared page tables will not be used for 4825 * OBJT_DEVICE or OBJT_MGTDEVICE (PG_FICTITIOUS) mappings 4826 * so PHYS_TO_VM_PAGE() should be safe here. 4827 */ 4828 pte = pmap_inval_smp(pmap, (vm_offset_t)-1, 1, ptep, 0); 4829 if (vm_page_unwire_quick(PHYS_TO_VM_PAGE(pte & PG_FRAME))) 4830 panic("pmap_protect: pgtable1 pg bad wirecount"); 4831 if (vm_page_unwire_quick(pt_pv->pv_m)) 4832 panic("pmap_protect: pgtable2 pg bad wirecount"); 4833 ptep = NULL; 4834 } 4835 /* else unmanaged page, adjust bits, no wire changes */ 4836 4837 if (ptep) { 4838 cbits &= ~pmap->pmap_bits[PG_RW_IDX]; 4839 #ifdef PMAP_DEBUG2 4840 if (pmap_enter_debug > 0) { 4841 --pmap_enter_debug; 4842 kprintf("pmap_protect va=%lx ptep=%p pte_pv=%p " 4843 "pt_pv=%p cbits=%08lx\n", 4844 va, ptep, pte_pv, 4845 pt_pv, cbits 4846 ); 4847 } 4848 #endif 4849 if (pbits != cbits) { 4850 vm_offset_t xva; 4851 4852 xva = (sharept) ? (vm_offset_t)-1 : va; 4853 if (!pmap_inval_smp_cmpset(pmap, xva, 4854 ptep, pbits, cbits)) { 4855 goto again; 4856 } 4857 } 4858 } 4859 if (pte_pv) 4860 pv_put(pte_pv); 4861 else 4862 pv_placemarker_wakeup(pmap, pte_placemark); 4863 } 4864 4865 /* 4866 * Insert the vm_page (m) at the virtual address (va), replacing any prior 4867 * mapping at that address. Set protection and wiring as requested. 4868 * 4869 * If entry is non-NULL we check to see if the SEG_SIZE optimization is 4870 * possible. If it is we enter the page into the appropriate shared pmap 4871 * hanging off the related VM object instead of the passed pmap, then we 4872 * share the page table page from the VM object's pmap into the current pmap. 4873 * 4874 * NOTE: This routine MUST insert the page into the pmap now, it cannot 4875 * lazy-evaluate. 4876 * 4877 * NOTE: If (m) is PG_UNMANAGED it may also be a temporary fake vm_page_t. 4878 * never record it. 4879 */ 4880 void 4881 pmap_enter(pmap_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot, 4882 boolean_t wired, vm_map_entry_t entry) 4883 { 4884 pv_entry_t pt_pv; /* page table */ 4885 pv_entry_t pte_pv; /* page table entry */ 4886 vm_pindex_t *pte_placemark; 4887 pt_entry_t *ptep; 4888 vm_paddr_t opa; 4889 pt_entry_t origpte, newpte; 4890 vm_paddr_t pa; 4891 4892 if (pmap == NULL) 4893 return; 4894 va = trunc_page(va); 4895 #ifdef PMAP_DIAGNOSTIC 4896 if (va >= KvaEnd) 4897 panic("pmap_enter: toobig"); 4898 if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS)) 4899 panic("pmap_enter: invalid to pmap_enter page table " 4900 "pages (va: 0x%lx)", va); 4901 #endif 4902 if (va < UPT_MAX_ADDRESS && pmap == &kernel_pmap) { 4903 kprintf("Warning: pmap_enter called on UVA with " 4904 "kernel_pmap\n"); 4905 #ifdef DDB 4906 db_print_backtrace(); 4907 #endif 4908 } 4909 if (va >= UPT_MAX_ADDRESS && pmap != &kernel_pmap) { 4910 kprintf("Warning: pmap_enter called on KVA without" 4911 "kernel_pmap\n"); 4912 #ifdef DDB 4913 db_print_backtrace(); 4914 #endif 4915 } 4916 4917 /* 4918 * Get locked PV entries for our new page table entry (pte_pv or 4919 * pte_placemark) and for its parent page table (pt_pv). We need 4920 * the parent so we can resolve the location of the ptep. 4921 * 4922 * Only hardware MMU actions can modify the ptep out from 4923 * under us. 4924 * 4925 * if (m) is fictitious or unmanaged we do not create a managing 4926 * pte_pv for it. Any pre-existing page's management state must 4927 * match (avoiding code complexity). 4928 * 4929 * If the pmap is still being initialized we assume existing 4930 * page tables. 4931 * 4932 * Kernel mapppings do not track page table pages (i.e. pt_pv). 4933 * 4934 * WARNING! If replacing a managed mapping with an unmanaged mapping 4935 * pte_pv will wind up being non-NULL and must be handled 4936 * below. 4937 */ 4938 if (pmap_initialized == FALSE) { 4939 pte_pv = NULL; 4940 pt_pv = NULL; 4941 pte_placemark = NULL; 4942 ptep = vtopte(va); 4943 origpte = *ptep; 4944 } else if (m->flags & (/*PG_FICTITIOUS |*/ PG_UNMANAGED)) { /* XXX */ 4945 pmap_softwait(pmap); 4946 pte_pv = pv_get(pmap, pmap_pte_pindex(va), &pte_placemark); 4947 KKASSERT(pte_pv == NULL); 4948 if (va >= VM_MAX_USER_ADDRESS) { 4949 pt_pv = NULL; 4950 ptep = vtopte(va); 4951 } else { 4952 pt_pv = pmap_allocpte_seg(pmap, pmap_pt_pindex(va), 4953 NULL, entry, va); 4954 ptep = pv_pte_lookup(pt_pv, pmap_pte_index(va)); 4955 } 4956 origpte = *ptep; 4957 cpu_ccfence(); 4958 KASSERT(origpte == 0 || 4959 (origpte & pmap->pmap_bits[PG_MANAGED_IDX]) == 0, 4960 ("Invalid PTE 0x%016jx @ 0x%016jx\n", origpte, va)); 4961 } else { 4962 pmap_softwait(pmap); 4963 if (va >= VM_MAX_USER_ADDRESS) { 4964 /* 4965 * Kernel map, pv_entry-tracked. 4966 */ 4967 pt_pv = NULL; 4968 pte_pv = pmap_allocpte(pmap, pmap_pte_pindex(va), NULL); 4969 ptep = vtopte(va); 4970 } else { 4971 /* 4972 * User map 4973 */ 4974 pte_pv = pmap_allocpte_seg(pmap, pmap_pte_pindex(va), 4975 &pt_pv, entry, va); 4976 ptep = pv_pte_lookup(pt_pv, pmap_pte_index(va)); 4977 } 4978 pte_placemark = NULL; /* safety */ 4979 origpte = *ptep; 4980 cpu_ccfence(); 4981 KASSERT(origpte == 0 || 4982 (origpte & pmap->pmap_bits[PG_MANAGED_IDX]), 4983 ("Invalid PTE 0x%016jx @ 0x%016jx\n", origpte, va)); 4984 } 4985 4986 pa = VM_PAGE_TO_PHYS(m); 4987 opa = origpte & PG_FRAME; 4988 4989 /* 4990 * Calculate the new PTE. Note that pte_pv alone does not mean 4991 * the new pte_pv is managed, it could exist because the old pte 4992 * was managed even if the new one is not. 4993 */ 4994 newpte = (pt_entry_t)(pa | pte_prot(pmap, prot) | 4995 pmap->pmap_bits[PG_V_IDX] | pmap->pmap_bits[PG_A_IDX]); 4996 if (wired) 4997 newpte |= pmap->pmap_bits[PG_W_IDX]; 4998 if (va < VM_MAX_USER_ADDRESS) 4999 newpte |= pmap->pmap_bits[PG_U_IDX]; 5000 if (pte_pv && (m->flags & (/*PG_FICTITIOUS |*/ PG_UNMANAGED)) == 0) 5001 newpte |= pmap->pmap_bits[PG_MANAGED_IDX]; 5002 // if (pmap == &kernel_pmap) 5003 // newpte |= pgeflag; 5004 newpte |= pmap->pmap_cache_bits[m->pat_mode]; 5005 if (m->flags & PG_FICTITIOUS) 5006 newpte |= pmap->pmap_bits[PG_DEVICE_IDX]; 5007 5008 /* 5009 * It is possible for multiple faults to occur in threaded 5010 * environments, the existing pte might be correct. 5011 */ 5012 if (((origpte ^ newpte) & 5013 ~(pt_entry_t)(pmap->pmap_bits[PG_M_IDX] | 5014 pmap->pmap_bits[PG_A_IDX])) == 0) { 5015 goto done; 5016 } 5017 5018 /* 5019 * Ok, either the address changed or the protection or wiring 5020 * changed. 5021 * 5022 * Clear the current entry, interlocking the removal. For managed 5023 * pte's this will also flush the modified state to the vm_page. 5024 * Atomic ops are mandatory in order to ensure that PG_M events are 5025 * not lost during any transition. 5026 * 5027 * WARNING: The caller has busied the new page but not the original 5028 * vm_page which we are trying to replace. Because we hold 5029 * the pte_pv lock, but have not busied the page, PG bits 5030 * can be cleared out from under us. 5031 */ 5032 if (opa) { 5033 if (origpte & pmap->pmap_bits[PG_MANAGED_IDX]) { 5034 /* 5035 * Old page was managed. Expect pte_pv to exist. 5036 * (it might also exist if the old page was unmanaged). 5037 * 5038 * NOTE: pt_pv won't exist for a kernel page 5039 * (managed or otherwise). 5040 * 5041 * NOTE: We may be reusing the pte_pv so we do not 5042 * destroy it in pmap_remove_pv_pte(). 5043 */ 5044 KKASSERT(pte_pv && pte_pv->pv_m); 5045 if (prot & VM_PROT_NOSYNC) { 5046 pmap_remove_pv_pte(pte_pv, pt_pv, NULL, 0); 5047 } else { 5048 pmap_inval_bulk_t bulk; 5049 5050 pmap_inval_bulk_init(&bulk, pmap); 5051 pmap_remove_pv_pte(pte_pv, pt_pv, &bulk, 0); 5052 pmap_inval_bulk_flush(&bulk); 5053 } 5054 pmap_remove_pv_page(pte_pv); 5055 /* will either set pte_pv->pv_m or pv_free() later */ 5056 } else { 5057 /* 5058 * Old page was not managed. If we have a pte_pv 5059 * it better not have a pv_m assigned to it. If the 5060 * new page is managed the pte_pv will be destroyed 5061 * near the end (we need its interlock). 5062 * 5063 * NOTE: We leave the wire count on the PT page 5064 * intact for the followup enter, but adjust 5065 * the wired-pages count on the pmap. 5066 */ 5067 KKASSERT(pte_pv == NULL); 5068 if (prot & VM_PROT_NOSYNC) { 5069 /* 5070 * NOSYNC (no mmu sync) requested. 5071 */ 5072 (void)pte_load_clear(ptep); 5073 cpu_invlpg((void *)va); 5074 } else { 5075 /* 5076 * Nominal SYNC 5077 */ 5078 pmap_inval_smp(pmap, va, 1, ptep, 0); 5079 } 5080 5081 /* 5082 * We must adjust pm_stats manually for unmanaged 5083 * pages. 5084 */ 5085 if (pt_pv) { 5086 atomic_add_long(&pmap->pm_stats. 5087 resident_count, -1); 5088 } 5089 if (origpte & pmap->pmap_bits[PG_W_IDX]) { 5090 atomic_add_long(&pmap->pm_stats. 5091 wired_count, -1); 5092 } 5093 } 5094 KKASSERT(*ptep == 0); 5095 } 5096 5097 #ifdef PMAP_DEBUG2 5098 if (pmap_enter_debug > 0) { 5099 --pmap_enter_debug; 5100 kprintf("pmap_enter: va=%lx m=%p origpte=%lx newpte=%lx ptep=%p" 5101 " pte_pv=%p pt_pv=%p opa=%lx prot=%02x\n", 5102 va, m, 5103 origpte, newpte, ptep, 5104 pte_pv, pt_pv, opa, prot); 5105 } 5106 #endif 5107 5108 if ((newpte & pmap->pmap_bits[PG_MANAGED_IDX]) == 0) { 5109 /* 5110 * Entering an unmanaged page. We must wire the pt_pv unless 5111 * we retained the wiring from an unmanaged page we had 5112 * removed (if we retained it via pte_pv that will go away 5113 * soon). 5114 */ 5115 if (pt_pv && (opa == 0 || 5116 (origpte & pmap->pmap_bits[PG_MANAGED_IDX]))) { 5117 vm_page_wire_quick(pt_pv->pv_m); 5118 } 5119 if (wired) 5120 atomic_add_long(&pmap->pm_stats.wired_count, 1); 5121 5122 /* 5123 * Unmanaged pages need manual resident_count tracking. 5124 */ 5125 if (pt_pv) { 5126 atomic_add_long(&pt_pv->pv_pmap->pm_stats. 5127 resident_count, 1); 5128 } 5129 if (newpte & pmap->pmap_bits[PG_RW_IDX]) 5130 vm_page_flag_set(m, PG_WRITEABLE); 5131 } else { 5132 /* 5133 * Entering a managed page. Our pte_pv takes care of the 5134 * PT wiring, so if we had removed an unmanaged page before 5135 * we must adjust. 5136 * 5137 * We have to take care of the pmap wired count ourselves. 5138 * 5139 * Enter on the PV list if part of our managed memory. 5140 */ 5141 KKASSERT(pte_pv && (pte_pv->pv_m == NULL || pte_pv->pv_m == m)); 5142 vm_page_spin_lock(m); 5143 pte_pv->pv_m = m; 5144 pmap_page_stats_adding(m); 5145 TAILQ_INSERT_TAIL(&m->md.pv_list, pte_pv, pv_list); 5146 vm_page_flag_set(m, PG_MAPPED); 5147 if (newpte & pmap->pmap_bits[PG_RW_IDX]) 5148 vm_page_flag_set(m, PG_WRITEABLE); 5149 vm_page_spin_unlock(m); 5150 5151 if (pt_pv && opa && 5152 (origpte & pmap->pmap_bits[PG_MANAGED_IDX]) == 0) { 5153 vm_page_unwire_quick(pt_pv->pv_m); 5154 } 5155 5156 /* 5157 * Adjust pmap wired pages count for new entry. 5158 */ 5159 if (wired) { 5160 atomic_add_long(&pte_pv->pv_pmap->pm_stats. 5161 wired_count, 1); 5162 } 5163 } 5164 5165 /* 5166 * Kernel VMAs (pt_pv == NULL) require pmap invalidation interlocks. 5167 * 5168 * User VMAs do not because those will be zero->non-zero, so no 5169 * stale entries to worry about at this point. 5170 * 5171 * For KVM there appear to still be issues. Theoretically we 5172 * should be able to scrap the interlocks entirely but we 5173 * get crashes. 5174 */ 5175 if ((prot & VM_PROT_NOSYNC) == 0 && pt_pv == NULL) { 5176 pmap_inval_smp(pmap, va, 1, ptep, newpte); 5177 } else { 5178 origpte = atomic_swap_long(ptep, newpte); 5179 if (origpte & pmap->pmap_bits[PG_M_IDX]) { 5180 kprintf("pmap [M] race @ %016jx\n", va); 5181 atomic_set_long(ptep, pmap->pmap_bits[PG_M_IDX]); 5182 } 5183 if (pt_pv == NULL) 5184 cpu_invlpg((void *)va); 5185 } 5186 5187 /* 5188 * Cleanup 5189 */ 5190 done: 5191 KKASSERT((newpte & pmap->pmap_bits[PG_MANAGED_IDX]) == 0 || 5192 (m->flags & PG_MAPPED)); 5193 5194 /* 5195 * Cleanup the pv entry, allowing other accessors. If the new page 5196 * is not managed but we have a pte_pv (which was locking our 5197 * operation), we can free it now. pte_pv->pv_m should be NULL. 5198 */ 5199 if (pte_pv && (newpte & pmap->pmap_bits[PG_MANAGED_IDX]) == 0) { 5200 pv_free(pte_pv, pt_pv); 5201 } else if (pte_pv) { 5202 pv_put(pte_pv); 5203 } else if (pte_placemark) { 5204 pv_placemarker_wakeup(pmap, pte_placemark); 5205 } 5206 if (pt_pv) 5207 pv_put(pt_pv); 5208 } 5209 5210 /* 5211 * This code works like pmap_enter() but assumes VM_PROT_READ and not-wired. 5212 * This code also assumes that the pmap has no pre-existing entry for this 5213 * VA. 5214 * 5215 * This code currently may only be used on user pmaps, not kernel_pmap. 5216 */ 5217 void 5218 pmap_enter_quick(pmap_t pmap, vm_offset_t va, vm_page_t m) 5219 { 5220 pmap_enter(pmap, va, m, VM_PROT_READ, FALSE, NULL); 5221 } 5222 5223 /* 5224 * Make a temporary mapping for a physical address. This is only intended 5225 * to be used for panic dumps. 5226 * 5227 * The caller is responsible for calling smp_invltlb(). 5228 */ 5229 void * 5230 pmap_kenter_temporary(vm_paddr_t pa, long i) 5231 { 5232 pmap_kenter_quick((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa); 5233 return ((void *)crashdumpmap); 5234 } 5235 5236 #define MAX_INIT_PT (96) 5237 5238 /* 5239 * This routine preloads the ptes for a given object into the specified pmap. 5240 * This eliminates the blast of soft faults on process startup and 5241 * immediately after an mmap. 5242 */ 5243 static int pmap_object_init_pt_callback(vm_page_t p, void *data); 5244 5245 void 5246 pmap_object_init_pt(pmap_t pmap, vm_offset_t addr, vm_prot_t prot, 5247 vm_object_t object, vm_pindex_t pindex, 5248 vm_size_t size, int limit) 5249 { 5250 struct rb_vm_page_scan_info info; 5251 struct lwp *lp; 5252 vm_size_t psize; 5253 5254 /* 5255 * We can't preinit if read access isn't set or there is no pmap 5256 * or object. 5257 */ 5258 if ((prot & VM_PROT_READ) == 0 || pmap == NULL || object == NULL) 5259 return; 5260 5261 /* 5262 * We can't preinit if the pmap is not the current pmap 5263 */ 5264 lp = curthread->td_lwp; 5265 if (lp == NULL || pmap != vmspace_pmap(lp->lwp_vmspace)) 5266 return; 5267 5268 /* 5269 * Misc additional checks 5270 */ 5271 psize = x86_64_btop(size); 5272 5273 if ((object->type != OBJT_VNODE) || 5274 ((limit & MAP_PREFAULT_PARTIAL) && (psize > MAX_INIT_PT) && 5275 (object->resident_page_count > MAX_INIT_PT))) { 5276 return; 5277 } 5278 5279 if (pindex + psize > object->size) { 5280 if (object->size < pindex) 5281 return; 5282 psize = object->size - pindex; 5283 } 5284 5285 if (psize == 0) 5286 return; 5287 5288 /* 5289 * If everything is segment-aligned do not pre-init here. Instead 5290 * allow the normal vm_fault path to pass a segment hint to 5291 * pmap_enter() which will then use an object-referenced shared 5292 * page table page. 5293 */ 5294 if ((addr & SEG_MASK) == 0 && 5295 (ctob(psize) & SEG_MASK) == 0 && 5296 (ctob(pindex) & SEG_MASK) == 0) { 5297 return; 5298 } 5299 5300 /* 5301 * Use a red-black scan to traverse the requested range and load 5302 * any valid pages found into the pmap. 5303 * 5304 * We cannot safely scan the object's memq without holding the 5305 * object token. 5306 */ 5307 info.start_pindex = pindex; 5308 info.end_pindex = pindex + psize - 1; 5309 info.limit = limit; 5310 info.mpte = NULL; 5311 info.addr = addr; 5312 info.pmap = pmap; 5313 info.object = object; 5314 5315 /* 5316 * By using the NOLK scan, the callback function must be sure 5317 * to return -1 if the VM page falls out of the object. 5318 */ 5319 vm_object_hold_shared(object); 5320 vm_page_rb_tree_RB_SCAN_NOLK(&object->rb_memq, rb_vm_page_scancmp, 5321 pmap_object_init_pt_callback, &info); 5322 vm_object_drop(object); 5323 } 5324 5325 static 5326 int 5327 pmap_object_init_pt_callback(vm_page_t p, void *data) 5328 { 5329 struct rb_vm_page_scan_info *info = data; 5330 vm_pindex_t rel_index; 5331 int hard_busy; 5332 5333 /* 5334 * don't allow an madvise to blow away our really 5335 * free pages allocating pv entries. 5336 */ 5337 if ((info->limit & MAP_PREFAULT_MADVISE) && 5338 vmstats.v_free_count < vmstats.v_free_reserved) { 5339 return(-1); 5340 } 5341 5342 /* 5343 * Ignore list markers and ignore pages we cannot instantly 5344 * busy (while holding the object token). 5345 */ 5346 if (p->flags & PG_MARKER) 5347 return 0; 5348 hard_busy = 0; 5349 again: 5350 if (hard_busy) { 5351 if (vm_page_busy_try(p, TRUE)) 5352 return 0; 5353 } else { 5354 if (vm_page_sbusy_try(p)) 5355 return 0; 5356 } 5357 if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) && 5358 (p->flags & PG_FICTITIOUS) == 0) { 5359 if ((p->queue - p->pc) == PQ_CACHE) { 5360 if (hard_busy == 0) { 5361 vm_page_sbusy_drop(p); 5362 hard_busy = 1; 5363 goto again; 5364 } 5365 vm_page_deactivate(p); 5366 } 5367 rel_index = p->pindex - info->start_pindex; 5368 pmap_enter_quick(info->pmap, 5369 info->addr + x86_64_ptob(rel_index), p); 5370 } 5371 if (hard_busy) 5372 vm_page_wakeup(p); 5373 else 5374 vm_page_sbusy_drop(p); 5375 5376 /* 5377 * We are using an unlocked scan (that is, the scan expects its 5378 * current element to remain in the tree on return). So we have 5379 * to check here and abort the scan if it isn't. 5380 */ 5381 if (p->object != info->object) 5382 return -1; 5383 lwkt_yield(); 5384 return(0); 5385 } 5386 5387 /* 5388 * Return TRUE if the pmap is in shape to trivially pre-fault the specified 5389 * address. 5390 * 5391 * Returns FALSE if it would be non-trivial or if a pte is already loaded 5392 * into the slot. 5393 * 5394 * XXX This is safe only because page table pages are not freed. 5395 */ 5396 int 5397 pmap_prefault_ok(pmap_t pmap, vm_offset_t addr) 5398 { 5399 pt_entry_t *pte; 5400 5401 /*spin_lock(&pmap->pm_spin);*/ 5402 if ((pte = pmap_pte(pmap, addr)) != NULL) { 5403 if (*pte & pmap->pmap_bits[PG_V_IDX]) { 5404 /*spin_unlock(&pmap->pm_spin);*/ 5405 return FALSE; 5406 } 5407 } 5408 /*spin_unlock(&pmap->pm_spin);*/ 5409 return TRUE; 5410 } 5411 5412 /* 5413 * Change the wiring attribute for a pmap/va pair. The mapping must already 5414 * exist in the pmap. The mapping may or may not be managed. The wiring in 5415 * the page is not changed, the page is returned so the caller can adjust 5416 * its wiring (the page is not locked in any way). 5417 * 5418 * Wiring is not a hardware characteristic so there is no need to invalidate 5419 * TLB. However, in an SMP environment we must use a locked bus cycle to 5420 * update the pte (if we are not using the pmap_inval_*() API that is)... 5421 * it's ok to do this for simple wiring changes. 5422 */ 5423 vm_page_t 5424 pmap_unwire(pmap_t pmap, vm_offset_t va) 5425 { 5426 pt_entry_t *ptep; 5427 pv_entry_t pt_pv; 5428 vm_paddr_t pa; 5429 vm_page_t m; 5430 5431 if (pmap == NULL) 5432 return NULL; 5433 5434 /* 5435 * Assume elements in the kernel pmap are stable 5436 */ 5437 if (pmap == &kernel_pmap) { 5438 if (pmap_pt(pmap, va) == 0) 5439 return NULL; 5440 ptep = pmap_pte_quick(pmap, va); 5441 if (pmap_pte_v(pmap, ptep)) { 5442 if (pmap_pte_w(pmap, ptep)) 5443 atomic_add_long(&pmap->pm_stats.wired_count,-1); 5444 atomic_clear_long(ptep, pmap->pmap_bits[PG_W_IDX]); 5445 pa = *ptep & PG_FRAME; 5446 m = PHYS_TO_VM_PAGE(pa); 5447 } else { 5448 m = NULL; 5449 } 5450 } else { 5451 /* 5452 * We can only [un]wire pmap-local pages (we cannot wire 5453 * shared pages) 5454 */ 5455 pt_pv = pv_get(pmap, pmap_pt_pindex(va), NULL); 5456 if (pt_pv == NULL) 5457 return NULL; 5458 5459 ptep = pv_pte_lookup(pt_pv, pmap_pte_index(va)); 5460 if ((*ptep & pmap->pmap_bits[PG_V_IDX]) == 0) { 5461 pv_put(pt_pv); 5462 return NULL; 5463 } 5464 5465 if (pmap_pte_w(pmap, ptep)) { 5466 atomic_add_long(&pt_pv->pv_pmap->pm_stats.wired_count, 5467 -1); 5468 } 5469 /* XXX else return NULL so caller doesn't unwire m ? */ 5470 5471 atomic_clear_long(ptep, pmap->pmap_bits[PG_W_IDX]); 5472 5473 pa = *ptep & PG_FRAME; 5474 m = PHYS_TO_VM_PAGE(pa); /* held by wired count */ 5475 pv_put(pt_pv); 5476 } 5477 return m; 5478 } 5479 5480 /* 5481 * Copy the range specified by src_addr/len from the source map to 5482 * the range dst_addr/len in the destination map. 5483 * 5484 * This routine is only advisory and need not do anything. 5485 */ 5486 void 5487 pmap_copy(pmap_t dst_pmap, pmap_t src_pmap, vm_offset_t dst_addr, 5488 vm_size_t len, vm_offset_t src_addr) 5489 { 5490 } 5491 5492 /* 5493 * pmap_zero_page: 5494 * 5495 * Zero the specified physical page. 5496 * 5497 * This function may be called from an interrupt and no locking is 5498 * required. 5499 */ 5500 void 5501 pmap_zero_page(vm_paddr_t phys) 5502 { 5503 vm_offset_t va = PHYS_TO_DMAP(phys); 5504 5505 pagezero((void *)va); 5506 } 5507 5508 /* 5509 * pmap_zero_page: 5510 * 5511 * Zero part of a physical page by mapping it into memory and clearing 5512 * its contents with bzero. 5513 * 5514 * off and size may not cover an area beyond a single hardware page. 5515 */ 5516 void 5517 pmap_zero_page_area(vm_paddr_t phys, int off, int size) 5518 { 5519 vm_offset_t virt = PHYS_TO_DMAP(phys); 5520 5521 bzero((char *)virt + off, size); 5522 } 5523 5524 /* 5525 * pmap_copy_page: 5526 * 5527 * Copy the physical page from the source PA to the target PA. 5528 * This function may be called from an interrupt. No locking 5529 * is required. 5530 */ 5531 void 5532 pmap_copy_page(vm_paddr_t src, vm_paddr_t dst) 5533 { 5534 vm_offset_t src_virt, dst_virt; 5535 5536 src_virt = PHYS_TO_DMAP(src); 5537 dst_virt = PHYS_TO_DMAP(dst); 5538 bcopy((void *)src_virt, (void *)dst_virt, PAGE_SIZE); 5539 } 5540 5541 /* 5542 * pmap_copy_page_frag: 5543 * 5544 * Copy the physical page from the source PA to the target PA. 5545 * This function may be called from an interrupt. No locking 5546 * is required. 5547 */ 5548 void 5549 pmap_copy_page_frag(vm_paddr_t src, vm_paddr_t dst, size_t bytes) 5550 { 5551 vm_offset_t src_virt, dst_virt; 5552 5553 src_virt = PHYS_TO_DMAP(src); 5554 dst_virt = PHYS_TO_DMAP(dst); 5555 5556 bcopy((char *)src_virt + (src & PAGE_MASK), 5557 (char *)dst_virt + (dst & PAGE_MASK), 5558 bytes); 5559 } 5560 5561 /* 5562 * Returns true if the pmap's pv is one of the first 16 pvs linked to from 5563 * this page. This count may be changed upwards or downwards in the future; 5564 * it is only necessary that true be returned for a small subset of pmaps 5565 * for proper page aging. 5566 */ 5567 boolean_t 5568 pmap_page_exists_quick(pmap_t pmap, vm_page_t m) 5569 { 5570 pv_entry_t pv; 5571 int loops = 0; 5572 5573 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 5574 return FALSE; 5575 5576 vm_page_spin_lock(m); 5577 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 5578 if (pv->pv_pmap == pmap) { 5579 vm_page_spin_unlock(m); 5580 return TRUE; 5581 } 5582 loops++; 5583 if (loops >= 16) 5584 break; 5585 } 5586 vm_page_spin_unlock(m); 5587 return (FALSE); 5588 } 5589 5590 /* 5591 * Remove all pages from specified address space this aids process exit 5592 * speeds. Also, this code may be special cased for the current process 5593 * only. 5594 */ 5595 void 5596 pmap_remove_pages(pmap_t pmap, vm_offset_t sva, vm_offset_t eva) 5597 { 5598 pmap_remove_noinval(pmap, sva, eva); 5599 cpu_invltlb(); 5600 } 5601 5602 /* 5603 * pmap_testbit tests bits in pte's note that the testbit/clearbit 5604 * routines are inline, and a lot of things compile-time evaluate. 5605 */ 5606 5607 static 5608 boolean_t 5609 pmap_testbit(vm_page_t m, int bit) 5610 { 5611 pv_entry_t pv; 5612 pt_entry_t *pte; 5613 pmap_t pmap; 5614 5615 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 5616 return FALSE; 5617 5618 if (TAILQ_FIRST(&m->md.pv_list) == NULL) 5619 return FALSE; 5620 vm_page_spin_lock(m); 5621 if (TAILQ_FIRST(&m->md.pv_list) == NULL) { 5622 vm_page_spin_unlock(m); 5623 return FALSE; 5624 } 5625 5626 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 5627 #if defined(PMAP_DIAGNOSTIC) 5628 if (pv->pv_pmap == NULL) { 5629 kprintf("Null pmap (tb) at pindex: %"PRIu64"\n", 5630 pv->pv_pindex); 5631 continue; 5632 } 5633 #endif 5634 pmap = pv->pv_pmap; 5635 5636 /* 5637 * If the bit being tested is the modified bit, then 5638 * mark clean_map and ptes as never 5639 * modified. 5640 * 5641 * WARNING! Because we do not lock the pv, *pte can be in a 5642 * state of flux. Despite this the value of *pte 5643 * will still be related to the vm_page in some way 5644 * because the pv cannot be destroyed as long as we 5645 * hold the vm_page spin lock. 5646 */ 5647 if (bit == PG_A_IDX || bit == PG_M_IDX) { 5648 //& (pmap->pmap_bits[PG_A_IDX] | pmap->pmap_bits[PG_M_IDX])) { 5649 if (!pmap_track_modified(pv->pv_pindex)) 5650 continue; 5651 } 5652 5653 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_pindex << PAGE_SHIFT); 5654 if (*pte & pmap->pmap_bits[bit]) { 5655 vm_page_spin_unlock(m); 5656 return TRUE; 5657 } 5658 } 5659 vm_page_spin_unlock(m); 5660 return (FALSE); 5661 } 5662 5663 /* 5664 * This routine is used to modify bits in ptes. Only one bit should be 5665 * specified. PG_RW requires special handling. 5666 * 5667 * Caller must NOT hold any spin locks 5668 */ 5669 static __inline 5670 void 5671 pmap_clearbit(vm_page_t m, int bit_index) 5672 { 5673 pv_entry_t pv; 5674 pt_entry_t *pte; 5675 pt_entry_t pbits; 5676 pmap_t pmap; 5677 5678 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) { 5679 if (bit_index == PG_RW_IDX) 5680 vm_page_flag_clear(m, PG_WRITEABLE); 5681 return; 5682 } 5683 5684 /* 5685 * PG_M or PG_A case 5686 * 5687 * Loop over all current mappings setting/clearing as appropos If 5688 * setting RO do we need to clear the VAC? 5689 * 5690 * NOTE: When clearing PG_M we could also (not implemented) drop 5691 * through to the PG_RW code and clear PG_RW too, forcing 5692 * a fault on write to redetect PG_M for virtual kernels, but 5693 * it isn't necessary since virtual kernels invalidate the 5694 * pte when they clear the VPTE_M bit in their virtual page 5695 * tables. 5696 * 5697 * NOTE: Does not re-dirty the page when clearing only PG_M. 5698 * 5699 * NOTE: Because we do not lock the pv, *pte can be in a state of 5700 * flux. Despite this the value of *pte is still somewhat 5701 * related while we hold the vm_page spin lock. 5702 * 5703 * *pte can be zero due to this race. Since we are clearing 5704 * bits we basically do no harm when this race occurs. 5705 */ 5706 if (bit_index != PG_RW_IDX) { 5707 vm_page_spin_lock(m); 5708 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 5709 #if defined(PMAP_DIAGNOSTIC) 5710 if (pv->pv_pmap == NULL) { 5711 kprintf("Null pmap (cb) at pindex: %"PRIu64"\n", 5712 pv->pv_pindex); 5713 continue; 5714 } 5715 #endif 5716 pmap = pv->pv_pmap; 5717 pte = pmap_pte_quick(pv->pv_pmap, 5718 pv->pv_pindex << PAGE_SHIFT); 5719 pbits = *pte; 5720 if (pbits & pmap->pmap_bits[bit_index]) 5721 atomic_clear_long(pte, pmap->pmap_bits[bit_index]); 5722 } 5723 vm_page_spin_unlock(m); 5724 return; 5725 } 5726 5727 /* 5728 * Clear PG_RW. Also clears PG_M and marks the page dirty if PG_M 5729 * was set. 5730 */ 5731 restart: 5732 vm_page_spin_lock(m); 5733 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 5734 /* 5735 * don't write protect pager mappings 5736 */ 5737 if (!pmap_track_modified(pv->pv_pindex)) 5738 continue; 5739 5740 #if defined(PMAP_DIAGNOSTIC) 5741 if (pv->pv_pmap == NULL) { 5742 kprintf("Null pmap (cb) at pindex: %"PRIu64"\n", 5743 pv->pv_pindex); 5744 continue; 5745 } 5746 #endif 5747 pmap = pv->pv_pmap; 5748 5749 /* 5750 * Skip pages which do not have PG_RW set. 5751 */ 5752 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_pindex << PAGE_SHIFT); 5753 if ((*pte & pmap->pmap_bits[PG_RW_IDX]) == 0) 5754 continue; 5755 5756 /* 5757 * We must lock the PV to be able to safely test the pte. 5758 */ 5759 if (pv_hold_try(pv)) { 5760 vm_page_spin_unlock(m); 5761 } else { 5762 vm_page_spin_unlock(m); 5763 pv_lock(pv); /* held, now do a blocking lock */ 5764 pv_put(pv); 5765 goto restart; 5766 } 5767 5768 /* 5769 * Reload pte after acquiring pv. 5770 */ 5771 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_pindex << PAGE_SHIFT); 5772 #if 0 5773 if ((*pte & pmap->pmap_bits[PG_RW_IDX]) == 0) { 5774 pv_put(pv); 5775 goto restart; 5776 } 5777 #endif 5778 5779 KKASSERT(pv->pv_pmap == pmap && pv->pv_m == m); 5780 for (;;) { 5781 pt_entry_t nbits; 5782 5783 pbits = *pte; 5784 cpu_ccfence(); 5785 nbits = pbits & ~(pmap->pmap_bits[PG_RW_IDX] | 5786 pmap->pmap_bits[PG_M_IDX]); 5787 if (pmap_inval_smp_cmpset(pmap, 5788 ((vm_offset_t)pv->pv_pindex << PAGE_SHIFT), 5789 pte, pbits, nbits)) { 5790 break; 5791 } 5792 cpu_pause(); 5793 } 5794 5795 /* 5796 * If PG_M was found to be set while we were clearing PG_RW 5797 * we also clear PG_M (done above) and mark the page dirty. 5798 * Callers expect this behavior. 5799 * 5800 * we lost pv so it cannot be used as an iterator. In fact, 5801 * because we couldn't necessarily lock it atomically it may 5802 * have moved within the list and ALSO cannot be used as an 5803 * iterator. 5804 */ 5805 vm_page_spin_lock(m); 5806 if (pbits & pmap->pmap_bits[PG_M_IDX]) 5807 vm_page_dirty(m); 5808 vm_page_spin_unlock(m); 5809 pv_put(pv); 5810 goto restart; 5811 } 5812 if (bit_index == PG_RW_IDX) 5813 vm_page_flag_clear(m, PG_WRITEABLE); 5814 vm_page_spin_unlock(m); 5815 } 5816 5817 /* 5818 * Lower the permission for all mappings to a given page. 5819 * 5820 * Page must be busied by caller. Because page is busied by caller this 5821 * should not be able to race a pmap_enter(). 5822 */ 5823 void 5824 pmap_page_protect(vm_page_t m, vm_prot_t prot) 5825 { 5826 /* JG NX support? */ 5827 if ((prot & VM_PROT_WRITE) == 0) { 5828 if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) { 5829 /* 5830 * NOTE: pmap_clearbit(.. PG_RW) also clears 5831 * the PG_WRITEABLE flag in (m). 5832 */ 5833 pmap_clearbit(m, PG_RW_IDX); 5834 } else { 5835 pmap_remove_all(m); 5836 } 5837 } 5838 } 5839 5840 vm_paddr_t 5841 pmap_phys_address(vm_pindex_t ppn) 5842 { 5843 return (x86_64_ptob(ppn)); 5844 } 5845 5846 /* 5847 * Return a count of reference bits for a page, clearing those bits. 5848 * It is not necessary for every reference bit to be cleared, but it 5849 * is necessary that 0 only be returned when there are truly no 5850 * reference bits set. 5851 * 5852 * XXX: The exact number of bits to check and clear is a matter that 5853 * should be tested and standardized at some point in the future for 5854 * optimal aging of shared pages. 5855 * 5856 * This routine may not block. 5857 */ 5858 int 5859 pmap_ts_referenced(vm_page_t m) 5860 { 5861 pv_entry_t pv; 5862 pt_entry_t *pte; 5863 pmap_t pmap; 5864 int rtval = 0; 5865 5866 if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) 5867 return (rtval); 5868 5869 vm_page_spin_lock(m); 5870 TAILQ_FOREACH(pv, &m->md.pv_list, pv_list) { 5871 if (!pmap_track_modified(pv->pv_pindex)) 5872 continue; 5873 pmap = pv->pv_pmap; 5874 pte = pmap_pte_quick(pv->pv_pmap, pv->pv_pindex << PAGE_SHIFT); 5875 if (pte && (*pte & pmap->pmap_bits[PG_A_IDX])) { 5876 atomic_clear_long(pte, pmap->pmap_bits[PG_A_IDX]); 5877 rtval++; 5878 if (rtval > 4) 5879 break; 5880 } 5881 } 5882 vm_page_spin_unlock(m); 5883 return (rtval); 5884 } 5885 5886 /* 5887 * pmap_is_modified: 5888 * 5889 * Return whether or not the specified physical page was modified 5890 * in any physical maps. 5891 */ 5892 boolean_t 5893 pmap_is_modified(vm_page_t m) 5894 { 5895 boolean_t res; 5896 5897 res = pmap_testbit(m, PG_M_IDX); 5898 return (res); 5899 } 5900 5901 /* 5902 * Clear the modify bits on the specified physical page. 5903 */ 5904 void 5905 pmap_clear_modify(vm_page_t m) 5906 { 5907 pmap_clearbit(m, PG_M_IDX); 5908 } 5909 5910 /* 5911 * pmap_clear_reference: 5912 * 5913 * Clear the reference bit on the specified physical page. 5914 */ 5915 void 5916 pmap_clear_reference(vm_page_t m) 5917 { 5918 pmap_clearbit(m, PG_A_IDX); 5919 } 5920 5921 /* 5922 * Miscellaneous support routines follow 5923 */ 5924 5925 static 5926 void 5927 i386_protection_init(void) 5928 { 5929 uint64_t *kp; 5930 int prot; 5931 5932 /* 5933 * NX supported? (boot time loader.conf override only) 5934 */ 5935 TUNABLE_INT_FETCH("machdep.pmap_nx_enable", &pmap_nx_enable); 5936 if (pmap_nx_enable == 0 || (amd_feature & AMDID_NX) == 0) 5937 pmap_bits_default[PG_NX_IDX] = 0; 5938 5939 /* 5940 * 0 is basically read-only access, but also set the NX (no-execute) 5941 * bit when VM_PROT_EXECUTE is not specified. 5942 */ 5943 kp = protection_codes; 5944 for (prot = 0; prot < PROTECTION_CODES_SIZE; prot++) { 5945 switch (prot) { 5946 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE: 5947 /* 5948 * This case handled elsewhere 5949 */ 5950 *kp++ = 0; 5951 break; 5952 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE: 5953 /* 5954 * Read-only is 0|NX 5955 */ 5956 *kp++ = pmap_bits_default[PG_NX_IDX]; 5957 break; 5958 case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE: 5959 case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE: 5960 /* 5961 * Execute requires read access 5962 */ 5963 *kp++ = 0; 5964 break; 5965 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE: 5966 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE: 5967 /* 5968 * Write without execute is RW|NX 5969 */ 5970 *kp++ = pmap_bits_default[PG_RW_IDX] | 5971 pmap_bits_default[PG_NX_IDX]; 5972 break; 5973 case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE: 5974 case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE: 5975 /* 5976 * Write with execute is RW 5977 */ 5978 *kp++ = pmap_bits_default[PG_RW_IDX]; 5979 break; 5980 } 5981 } 5982 } 5983 5984 /* 5985 * Map a set of physical memory pages into the kernel virtual 5986 * address space. Return a pointer to where it is mapped. This 5987 * routine is intended to be used for mapping device memory, 5988 * NOT real memory. 5989 * 5990 * NOTE: We can't use pgeflag unless we invalidate the pages one at 5991 * a time. 5992 * 5993 * NOTE: The PAT attributes {WRITE_BACK, WRITE_THROUGH, UNCACHED, UNCACHEABLE} 5994 * work whether the cpu supports PAT or not. The remaining PAT 5995 * attributes {WRITE_PROTECTED, WRITE_COMBINING} only work if the cpu 5996 * supports PAT. 5997 */ 5998 void * 5999 pmap_mapdev(vm_paddr_t pa, vm_size_t size) 6000 { 6001 return(pmap_mapdev_attr(pa, size, PAT_WRITE_BACK)); 6002 } 6003 6004 void * 6005 pmap_mapdev_uncacheable(vm_paddr_t pa, vm_size_t size) 6006 { 6007 return(pmap_mapdev_attr(pa, size, PAT_UNCACHEABLE)); 6008 } 6009 6010 void * 6011 pmap_mapbios(vm_paddr_t pa, vm_size_t size) 6012 { 6013 return (pmap_mapdev_attr(pa, size, PAT_WRITE_BACK)); 6014 } 6015 6016 /* 6017 * Map a set of physical memory pages into the kernel virtual 6018 * address space. Return a pointer to where it is mapped. This 6019 * routine is intended to be used for mapping device memory, 6020 * NOT real memory. 6021 */ 6022 void * 6023 pmap_mapdev_attr(vm_paddr_t pa, vm_size_t size, int mode) 6024 { 6025 vm_offset_t va, tmpva, offset; 6026 pt_entry_t *pte; 6027 vm_size_t tmpsize; 6028 6029 offset = pa & PAGE_MASK; 6030 size = roundup(offset + size, PAGE_SIZE); 6031 6032 va = kmem_alloc_nofault(&kernel_map, size, VM_SUBSYS_MAPDEV, PAGE_SIZE); 6033 if (va == 0) 6034 panic("pmap_mapdev: Couldn't alloc kernel virtual memory"); 6035 6036 pa = pa & ~PAGE_MASK; 6037 for (tmpva = va, tmpsize = size; tmpsize > 0;) { 6038 pte = vtopte(tmpva); 6039 *pte = pa | 6040 kernel_pmap.pmap_bits[PG_RW_IDX] | 6041 kernel_pmap.pmap_bits[PG_V_IDX] | /* pgeflag | */ 6042 kernel_pmap.pmap_cache_bits[mode]; 6043 tmpsize -= PAGE_SIZE; 6044 tmpva += PAGE_SIZE; 6045 pa += PAGE_SIZE; 6046 } 6047 pmap_invalidate_range(&kernel_pmap, va, va + size); 6048 pmap_invalidate_cache_range(va, va + size); 6049 6050 return ((void *)(va + offset)); 6051 } 6052 6053 void 6054 pmap_unmapdev(vm_offset_t va, vm_size_t size) 6055 { 6056 vm_offset_t base, offset; 6057 6058 base = va & ~PAGE_MASK; 6059 offset = va & PAGE_MASK; 6060 size = roundup(offset + size, PAGE_SIZE); 6061 pmap_qremove(va, size >> PAGE_SHIFT); 6062 kmem_free(&kernel_map, base, size); 6063 } 6064 6065 /* 6066 * Sets the memory attribute for the specified page. 6067 */ 6068 void 6069 pmap_page_set_memattr(vm_page_t m, vm_memattr_t ma) 6070 { 6071 6072 m->pat_mode = ma; 6073 6074 /* 6075 * If "m" is a normal page, update its direct mapping. This update 6076 * can be relied upon to perform any cache operations that are 6077 * required for data coherence. 6078 */ 6079 if ((m->flags & PG_FICTITIOUS) == 0) 6080 pmap_change_attr(PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m)), 1, m->pat_mode); 6081 } 6082 6083 /* 6084 * Change the PAT attribute on an existing kernel memory map. Caller 6085 * must ensure that the virtual memory in question is not accessed 6086 * during the adjustment. 6087 */ 6088 void 6089 pmap_change_attr(vm_offset_t va, vm_size_t count, int mode) 6090 { 6091 pt_entry_t *pte; 6092 vm_offset_t base; 6093 int changed = 0; 6094 6095 if (va == 0) 6096 panic("pmap_change_attr: va is NULL"); 6097 base = trunc_page(va); 6098 6099 while (count) { 6100 pte = vtopte(va); 6101 *pte = (*pte & ~(pt_entry_t)(kernel_pmap.pmap_cache_mask)) | 6102 kernel_pmap.pmap_cache_bits[mode]; 6103 --count; 6104 va += PAGE_SIZE; 6105 } 6106 6107 changed = 1; /* XXX: not optimal */ 6108 6109 /* 6110 * Flush CPU caches if required to make sure any data isn't cached that 6111 * shouldn't be, etc. 6112 */ 6113 if (changed) { 6114 pmap_invalidate_range(&kernel_pmap, base, va); 6115 pmap_invalidate_cache_range(base, va); 6116 } 6117 } 6118 6119 /* 6120 * perform the pmap work for mincore 6121 */ 6122 int 6123 pmap_mincore(pmap_t pmap, vm_offset_t addr) 6124 { 6125 pt_entry_t *ptep, pte; 6126 vm_page_t m; 6127 int val = 0; 6128 6129 ptep = pmap_pte(pmap, addr); 6130 6131 if (ptep && (pte = *ptep) != 0) { 6132 vm_offset_t pa; 6133 6134 val = MINCORE_INCORE; 6135 if ((pte & pmap->pmap_bits[PG_MANAGED_IDX]) == 0) 6136 goto done; 6137 6138 pa = pte & PG_FRAME; 6139 6140 if (pte & pmap->pmap_bits[PG_DEVICE_IDX]) 6141 m = NULL; 6142 else 6143 m = PHYS_TO_VM_PAGE(pa); 6144 6145 /* 6146 * Modified by us 6147 */ 6148 if (pte & pmap->pmap_bits[PG_M_IDX]) 6149 val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER; 6150 /* 6151 * Modified by someone 6152 */ 6153 else if (m && (m->dirty || pmap_is_modified(m))) 6154 val |= MINCORE_MODIFIED_OTHER; 6155 /* 6156 * Referenced by us 6157 */ 6158 if (pte & pmap->pmap_bits[PG_A_IDX]) 6159 val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER; 6160 6161 /* 6162 * Referenced by someone 6163 */ 6164 else if (m && ((m->flags & PG_REFERENCED) || 6165 pmap_ts_referenced(m))) { 6166 val |= MINCORE_REFERENCED_OTHER; 6167 vm_page_flag_set(m, PG_REFERENCED); 6168 } 6169 } 6170 done: 6171 6172 return val; 6173 } 6174 6175 /* 6176 * Replace p->p_vmspace with a new one. If adjrefs is non-zero the new 6177 * vmspace will be ref'd and the old one will be deref'd. 6178 * 6179 * The vmspace for all lwps associated with the process will be adjusted 6180 * and cr3 will be reloaded if any lwp is the current lwp. 6181 * 6182 * The process must hold the vmspace->vm_map.token for oldvm and newvm 6183 */ 6184 void 6185 pmap_replacevm(struct proc *p, struct vmspace *newvm, int adjrefs) 6186 { 6187 struct vmspace *oldvm; 6188 struct lwp *lp; 6189 6190 oldvm = p->p_vmspace; 6191 if (oldvm != newvm) { 6192 if (adjrefs) 6193 vmspace_ref(newvm); 6194 p->p_vmspace = newvm; 6195 KKASSERT(p->p_nthreads == 1); 6196 lp = RB_ROOT(&p->p_lwp_tree); 6197 pmap_setlwpvm(lp, newvm); 6198 if (adjrefs) 6199 vmspace_rel(oldvm); 6200 } 6201 } 6202 6203 /* 6204 * Set the vmspace for a LWP. The vmspace is almost universally set the 6205 * same as the process vmspace, but virtual kernels need to swap out contexts 6206 * on a per-lwp basis. 6207 * 6208 * Caller does not necessarily hold any vmspace tokens. Caller must control 6209 * the lwp (typically be in the context of the lwp). We use a critical 6210 * section to protect against statclock and hardclock (statistics collection). 6211 */ 6212 void 6213 pmap_setlwpvm(struct lwp *lp, struct vmspace *newvm) 6214 { 6215 struct vmspace *oldvm; 6216 struct pmap *pmap; 6217 6218 oldvm = lp->lwp_vmspace; 6219 6220 if (oldvm != newvm) { 6221 crit_enter(); 6222 KKASSERT((newvm->vm_refcnt & VM_REF_DELETED) == 0); 6223 lp->lwp_vmspace = newvm; 6224 if (curthread->td_lwp == lp) { 6225 pmap = vmspace_pmap(newvm); 6226 ATOMIC_CPUMASK_ORBIT(pmap->pm_active, mycpu->gd_cpuid); 6227 if (pmap->pm_active_lock & CPULOCK_EXCL) 6228 pmap_interlock_wait(newvm); 6229 #if defined(SWTCH_OPTIM_STATS) 6230 tlb_flush_count++; 6231 #endif 6232 if (pmap->pmap_bits[TYPE_IDX] == REGULAR_PMAP) { 6233 curthread->td_pcb->pcb_cr3 = vtophys(pmap->pm_pml4); 6234 } else if (pmap->pmap_bits[TYPE_IDX] == EPT_PMAP) { 6235 curthread->td_pcb->pcb_cr3 = KPML4phys; 6236 } else { 6237 panic("pmap_setlwpvm: unknown pmap type\n"); 6238 } 6239 load_cr3(curthread->td_pcb->pcb_cr3); 6240 pmap = vmspace_pmap(oldvm); 6241 ATOMIC_CPUMASK_NANDBIT(pmap->pm_active, 6242 mycpu->gd_cpuid); 6243 } 6244 crit_exit(); 6245 } 6246 } 6247 6248 /* 6249 * Called when switching to a locked pmap, used to interlock against pmaps 6250 * undergoing modifications to prevent us from activating the MMU for the 6251 * target pmap until all such modifications have completed. We have to do 6252 * this because the thread making the modifications has already set up its 6253 * SMP synchronization mask. 6254 * 6255 * This function cannot sleep! 6256 * 6257 * No requirements. 6258 */ 6259 void 6260 pmap_interlock_wait(struct vmspace *vm) 6261 { 6262 struct pmap *pmap = &vm->vm_pmap; 6263 6264 if (pmap->pm_active_lock & CPULOCK_EXCL) { 6265 crit_enter(); 6266 KKASSERT(curthread->td_critcount >= 2); 6267 DEBUG_PUSH_INFO("pmap_interlock_wait"); 6268 while (pmap->pm_active_lock & CPULOCK_EXCL) { 6269 cpu_ccfence(); 6270 lwkt_process_ipiq(); 6271 } 6272 DEBUG_POP_INFO(); 6273 crit_exit(); 6274 } 6275 } 6276 6277 vm_offset_t 6278 pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size) 6279 { 6280 6281 if ((obj == NULL) || (size < NBPDR) || 6282 ((obj->type != OBJT_DEVICE) && (obj->type != OBJT_MGTDEVICE))) { 6283 return addr; 6284 } 6285 6286 addr = roundup2(addr, NBPDR); 6287 return addr; 6288 } 6289 6290 /* 6291 * Used by kmalloc/kfree, page already exists at va 6292 */ 6293 vm_page_t 6294 pmap_kvtom(vm_offset_t va) 6295 { 6296 pt_entry_t *ptep = vtopte(va); 6297 6298 KKASSERT((*ptep & kernel_pmap.pmap_bits[PG_DEVICE_IDX]) == 0); 6299 return(PHYS_TO_VM_PAGE(*ptep & PG_FRAME)); 6300 } 6301 6302 /* 6303 * Initialize machine-specific shared page directory support. This 6304 * is executed when a VM object is created. 6305 */ 6306 void 6307 pmap_object_init(vm_object_t object) 6308 { 6309 object->md.pmap_rw = NULL; 6310 object->md.pmap_ro = NULL; 6311 } 6312 6313 /* 6314 * Clean up machine-specific shared page directory support. This 6315 * is executed when a VM object is destroyed. 6316 */ 6317 void 6318 pmap_object_free(vm_object_t object) 6319 { 6320 pmap_t pmap; 6321 6322 if ((pmap = object->md.pmap_rw) != NULL) { 6323 object->md.pmap_rw = NULL; 6324 pmap_remove_noinval(pmap, 6325 VM_MIN_USER_ADDRESS, VM_MAX_USER_ADDRESS); 6326 CPUMASK_ASSZERO(pmap->pm_active); 6327 pmap_release(pmap); 6328 pmap_puninit(pmap); 6329 kfree(pmap, M_OBJPMAP); 6330 } 6331 if ((pmap = object->md.pmap_ro) != NULL) { 6332 object->md.pmap_ro = NULL; 6333 pmap_remove_noinval(pmap, 6334 VM_MIN_USER_ADDRESS, VM_MAX_USER_ADDRESS); 6335 CPUMASK_ASSZERO(pmap->pm_active); 6336 pmap_release(pmap); 6337 pmap_puninit(pmap); 6338 kfree(pmap, M_OBJPMAP); 6339 } 6340 } 6341 6342 /* 6343 * pmap_pgscan_callback - Used by pmap_pgscan to acquire the related 6344 * VM page and issue a pginfo->callback. 6345 * 6346 * We are expected to dispose of any non-NULL pte_pv. 6347 */ 6348 static 6349 void 6350 pmap_pgscan_callback(pmap_t pmap, struct pmap_scan_info *info, 6351 pv_entry_t pte_pv, vm_pindex_t *pte_placemark, 6352 pv_entry_t pt_pv, int sharept, 6353 vm_offset_t va, pt_entry_t *ptep, void *arg) 6354 { 6355 struct pmap_pgscan_info *pginfo = arg; 6356 vm_page_t m; 6357 6358 if (pte_pv) { 6359 /* 6360 * Try to busy the page while we hold the pte_pv locked. 6361 */ 6362 KKASSERT(pte_pv->pv_m); 6363 m = PHYS_TO_VM_PAGE(*ptep & PG_FRAME); 6364 if (vm_page_busy_try(m, TRUE) == 0) { 6365 if (m == PHYS_TO_VM_PAGE(*ptep & PG_FRAME)) { 6366 /* 6367 * The callback is issued with the pte_pv 6368 * unlocked and put away, and the pt_pv 6369 * unlocked. 6370 */ 6371 pv_put(pte_pv); 6372 if (pt_pv) { 6373 vm_page_wire_quick(pt_pv->pv_m); 6374 pv_unlock(pt_pv); 6375 } 6376 if (pginfo->callback(pginfo, va, m) < 0) 6377 info->stop = 1; 6378 if (pt_pv) { 6379 pv_lock(pt_pv); 6380 vm_page_unwire_quick(pt_pv->pv_m); 6381 } 6382 } else { 6383 vm_page_wakeup(m); 6384 pv_put(pte_pv); 6385 } 6386 } else { 6387 ++pginfo->busycount; 6388 pv_put(pte_pv); 6389 } 6390 } else { 6391 /* 6392 * Shared page table or unmanaged page (sharept or !sharept) 6393 */ 6394 pv_placemarker_wakeup(pmap, pte_placemark); 6395 } 6396 } 6397 6398 void 6399 pmap_pgscan(struct pmap_pgscan_info *pginfo) 6400 { 6401 struct pmap_scan_info info; 6402 6403 pginfo->offset = pginfo->beg_addr; 6404 info.pmap = pginfo->pmap; 6405 info.sva = pginfo->beg_addr; 6406 info.eva = pginfo->end_addr; 6407 info.func = pmap_pgscan_callback; 6408 info.arg = pginfo; 6409 pmap_scan(&info, 0); 6410 if (info.stop == 0) 6411 pginfo->offset = pginfo->end_addr; 6412 } 6413 6414 /* 6415 * Wait for a placemarker that we do not own to clear. The placemarker 6416 * in question is not necessarily set to the pindex we want, we may have 6417 * to wait on the element because we want to reserve it ourselves. 6418 * 6419 * NOTE: PM_PLACEMARK_WAKEUP sets a bit which is already set in 6420 * PM_NOPLACEMARK, so it does not interfere with placemarks 6421 * which have already been woken up. 6422 */ 6423 static 6424 void 6425 pv_placemarker_wait(pmap_t pmap, vm_pindex_t *pmark) 6426 { 6427 if (*pmark != PM_NOPLACEMARK) { 6428 atomic_set_long(pmark, PM_PLACEMARK_WAKEUP); 6429 tsleep_interlock(pmark, 0); 6430 if (*pmark != PM_NOPLACEMARK) 6431 tsleep(pmark, PINTERLOCKED, "pvplw", 0); 6432 } 6433 } 6434 6435 /* 6436 * Wakeup a placemarker that we own. Replace the entry with 6437 * PM_NOPLACEMARK and issue a wakeup() if necessary. 6438 */ 6439 static 6440 void 6441 pv_placemarker_wakeup(pmap_t pmap, vm_pindex_t *pmark) 6442 { 6443 vm_pindex_t pindex; 6444 6445 pindex = atomic_swap_long(pmark, PM_NOPLACEMARK); 6446 KKASSERT(pindex != PM_NOPLACEMARK); 6447 if (pindex & PM_PLACEMARK_WAKEUP) 6448 wakeup(pmark); 6449 } 6450