pmap_segtab.c revision 1.19
1 /* $NetBSD: pmap_segtab.c,v 1.19 2020/08/20 05:54:32 mrg Exp $ */ 2 3 /*- 4 * Copyright (c) 1998, 2001 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center and by Chris G. Demetriou. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * Copyright (c) 1992, 1993 35 * The Regents of the University of California. All rights reserved. 36 * 37 * This code is derived from software contributed to Berkeley by 38 * the Systems Programming Group of the University of Utah Computer 39 * Science Department and Ralph Campbell. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 3. Neither the name of the University nor the names of its contributors 50 * may be used to endorse or promote products derived from this software 51 * without specific prior written permission. 52 * 53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 56 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 63 * SUCH DAMAGE. 64 * 65 * @(#)pmap.c 8.4 (Berkeley) 1/26/94 66 */ 67 68 #include <sys/cdefs.h> 69 70 __KERNEL_RCSID(0, "$NetBSD: pmap_segtab.c,v 1.19 2020/08/20 05:54:32 mrg Exp $"); 71 72 /* 73 * Manages physical address maps. 74 * 75 * In addition to hardware address maps, this 76 * module is called upon to provide software-use-only 77 * maps which may or may not be stored in the same 78 * form as hardware maps. These pseudo-maps are 79 * used to store intermediate results from copy 80 * operations to and from address spaces. 81 * 82 * Since the information managed by this module is 83 * also stored by the logical address mapping module, 84 * this module may throw away valid virtual-to-physical 85 * mappings at almost any time. However, invalidations 86 * of virtual-to-physical mappings must be done as 87 * requested. 88 * 89 * In order to cope with hardware architectures which 90 * make virtual-to-physical map invalidates expensive, 91 * this module may delay invalidate or reduced protection 92 * operations until such time as they are actually 93 * necessary. This module is given full information as 94 * to which processors are currently using which maps, 95 * and to when physical maps must be made correct. 96 */ 97 98 #define __PMAP_PRIVATE 99 100 #include "opt_multiprocessor.h" 101 102 #include <sys/param.h> 103 104 #include <sys/atomic.h> 105 #include <sys/mutex.h> 106 #include <sys/proc.h> 107 #include <sys/systm.h> 108 109 #include <uvm/uvm.h> 110 111 CTASSERT(NBPG >= sizeof(pmap_segtab_t)); 112 113 struct pmap_segtab_info { 114 pmap_segtab_t *free_segtab; /* free list kept locally */ 115 #ifdef DEBUG 116 uint32_t nget_segtab; 117 uint32_t nput_segtab; 118 uint32_t npage_segtab; 119 #define SEGTAB_ADD(n, v) (pmap_segtab_info.n ## _segtab += (v)) 120 #else 121 #define SEGTAB_ADD(n, v) ((void) 0) 122 #endif 123 #ifdef PMAP_PTP_CACHE 124 struct pgflist ptp_pgflist; /* Keep a list of idle page tables. */ 125 #endif 126 } pmap_segtab_info = { 127 #ifdef PMAP_PTP_CACHE 128 .ptp_pgflist = LIST_HEAD_INITIALIZER(pmap_segtab_info.ptp_pgflist), 129 #endif 130 }; 131 132 kmutex_t pmap_segtab_lock __cacheline_aligned; 133 134 /* 135 * Check that a seg_tab[] array is empty. 136 * 137 * This is used when allocating or freeing a pmap_segtab_t. The stp 138 * should be unused -- meaning, none of the seg_tab[] pointers are 139 * not NULL, as it transitions from either freshly allocated segtab from 140 * pmap pool, an unused allocated page segtab alloc from the SMP case, 141 * where two CPUs attempt to allocate the same underlying segtab, the 142 * release of a segtab entry to the freelist, or for SMP, where reserve 143 * also frees a freshly allocated but unused entry. 144 */ 145 static void 146 pmap_check_stp(pmap_segtab_t *stp, const char *caller, const char *why) 147 { 148 #ifdef DEBUG 149 for (size_t i = 0; i < PMAP_SEGTABSIZE; i++) { 150 if (stp->seg_tab[i] != NULL) { 151 #define DEBUG_NOISY 152 #ifdef DEBUG_NOISY 153 UVMHIST_FUNC(__func__); 154 UVMHIST_CALLARGS(pmapsegtabhist, "stp=%#jx", 155 (uintptr_t)stp, 0, 0, 0); 156 for (size_t j = i; j < PMAP_SEGTABSIZE; j++) 157 if (stp->seg_tab[j] != NULL) 158 printf("%s: stp->seg_tab[%zu] = %p\n", 159 caller, j, stp->seg_tab[j]); 160 #endif 161 panic("%s: pm_segtab.seg_tab[%zu] != 0 (%p): %s", 162 caller, i, stp->seg_tab[i], why); 163 } 164 } 165 #endif 166 } 167 168 /* 169 * Check that an array of ptes is actually zero. 170 */ 171 static void 172 pmap_check_ptes(pt_entry_t *pte, const char *caller) 173 { 174 #ifdef DEBUG 175 for (size_t i = 0; i < NPTEPG; i++) 176 if (!pte_zero_p(pte[i])) { 177 #ifdef DEBUG_NOISY 178 UVMHIST_FUNC(__func__); 179 UVMHIST_CALLARGS(pmapsegtabhist, "pte=%#jx", 180 (uintptr_t)pte, 0, 0, 0); 181 for (size_t j = i + 1; j < NPTEPG; j++) 182 if (!pte_zero_p(pte[j])) 183 UVMHIST_LOG(pmapsegtabhist, 184 "pte[%zu] = %#"PRIxPTE, 185 j, pte_value(pte[j]), 0, 0); 186 #endif 187 panic("%s: pte[%ju] entry at %pu not 0 (%#"PRIxPTE")", 188 caller, i, &pte[i], pte_value(pte[i])); 189 } 190 #endif 191 } 192 193 static inline struct vm_page * 194 pmap_pte_pagealloc(void) 195 { 196 struct vm_page *pg; 197 198 pg = PMAP_ALLOC_POOLPAGE(UVM_PGA_ZERO|UVM_PGA_USERESERVE); 199 if (pg) { 200 #ifdef UVM_PAGE_TRKOWN 201 pg->owner_tag = NULL; 202 #endif 203 UVM_PAGE_OWN(pg, "pmap-ptp"); 204 } 205 206 return pg; 207 } 208 209 static inline pt_entry_t * 210 pmap_segmap(struct pmap *pmap, vaddr_t va) 211 { 212 pmap_segtab_t *stp = pmap->pm_segtab; 213 KASSERTMSG(pmap != pmap_kernel() || !pmap_md_direct_mapped_vaddr_p(va), 214 "pmap %p va %#" PRIxVADDR, pmap, va); 215 #ifdef _LP64 216 stp = stp->seg_seg[(va >> XSEGSHIFT) & (NSEGPG - 1)]; 217 if (stp == NULL) 218 return NULL; 219 #endif 220 221 return stp->seg_tab[(va >> SEGSHIFT) & (PMAP_SEGTABSIZE - 1)]; 222 } 223 224 pt_entry_t * 225 pmap_pte_lookup(pmap_t pmap, vaddr_t va) 226 { 227 pt_entry_t *pte = pmap_segmap(pmap, va); 228 if (pte == NULL) 229 return NULL; 230 231 return pte + ((va >> PGSHIFT) & (NPTEPG - 1)); 232 } 233 234 /* 235 * Insert the segtab into the segtab freelist. 236 */ 237 static void 238 pmap_segtab_free(pmap_segtab_t *stp) 239 { 240 UVMHIST_FUNC(__func__); 241 242 UVMHIST_CALLARGS(pmapsegtabhist, "stp=%#jx", stp, 0, 0, 0); 243 244 mutex_spin_enter(&pmap_segtab_lock); 245 stp->seg_seg[0] = pmap_segtab_info.free_segtab; 246 pmap_segtab_info.free_segtab = stp; 247 SEGTAB_ADD(nput, 1); 248 mutex_spin_exit(&pmap_segtab_lock); 249 } 250 251 static void 252 pmap_segtab_release(pmap_t pmap, pmap_segtab_t **stp_p, bool free_stp, 253 pte_callback_t callback, uintptr_t flags, 254 vaddr_t va, vsize_t vinc) 255 { 256 pmap_segtab_t *stp = *stp_p; 257 258 UVMHIST_FUNC(__func__); 259 UVMHIST_CALLARGS(pmapsegtabhist, "pm=%#jx stpp=%#jx free=%jd", 260 (uintptr_t)pmap, (uintptr_t)stp_p, free_stp, 0); 261 UVMHIST_LOG(pmapsegtabhist, " callback=%jx flags=%jx va=%jx vinc=%jx", 262 (uintptr_t)callback, flags, (uintptr_t)va, (uintptr_t)vinc); 263 for (size_t i = (va / vinc) & (PMAP_SEGTABSIZE - 1); 264 i < PMAP_SEGTABSIZE; 265 i++, va += vinc) { 266 #ifdef _LP64 267 if (vinc > NBSEG) { 268 if (stp->seg_seg[i] != NULL) { 269 UVMHIST_LOG(pmapsegtabhist, 270 " recursing %jd", i, 0, 0, 0); 271 pmap_segtab_release(pmap, &stp->seg_seg[i], 272 true, callback, flags, va, vinc / NSEGPG); 273 KASSERT(stp->seg_seg[i] == NULL); 274 } 275 continue; 276 } 277 #endif 278 KASSERT(vinc == NBSEG); 279 280 /* get pointer to segment map */ 281 pt_entry_t *pte = stp->seg_tab[i]; 282 if (pte == NULL) 283 continue; 284 pmap_check_ptes(pte, __func__); 285 286 #if defined(__mips_n64) && PAGE_SIZE == 8192 287 /* 288 * XXX This is evil. If vinc is 1000000 we are in 289 * the last level, and this pte should be page aligned. 290 */ 291 if (vinc == 0x1000000 && ((uintptr_t)pte & PAGE_MASK) != 0) { 292 panic("%s: pte entry at %p not page aligned", 293 __func__, pte); 294 } 295 #endif 296 297 /* 298 * If our caller wants a callback, do so. 299 */ 300 if (callback != NULL) { 301 (*callback)(pmap, va, va + vinc, pte, flags); 302 } 303 304 // PMAP_UNMAP_POOLPAGE should handle any VCA issues itself 305 paddr_t pa = PMAP_UNMAP_POOLPAGE((vaddr_t)pte); 306 struct vm_page *pg = PHYS_TO_VM_PAGE(pa); 307 #ifdef PMAP_PTP_CACHE 308 mutex_spin_enter(&pmap_segtab_lock); 309 LIST_INSERT_HEAD(&pmap_segtab_info.ptp_pgflist, pg, pageq.list); 310 mutex_spin_exit(&pmap_segtab_lock); 311 #else 312 uvm_pagefree(pg); 313 #endif 314 315 stp->seg_tab[i] = NULL; 316 UVMHIST_LOG(pmapsegtabhist, " zeroing tab[%jd]", i, 0, 0, 0); 317 } 318 319 if (free_stp) { 320 pmap_check_stp(stp, __func__, 321 vinc == NBSEG ? "release seg" : "release xseg"); 322 pmap_segtab_free(stp); 323 *stp_p = NULL; 324 } 325 } 326 327 /* 328 * Create and return a physical map. 329 * 330 * If the size specified for the map 331 * is zero, the map is an actual physical 332 * map, and may be referenced by the 333 * hardware. 334 * 335 * If the size specified is non-zero, 336 * the map will be used in software only, and 337 * is bounded by that size. 338 */ 339 static pmap_segtab_t * 340 pmap_segtab_alloc(void) 341 { 342 pmap_segtab_t *stp; 343 bool found_on_freelist = false; 344 345 UVMHIST_FUNC(__func__); 346 again: 347 mutex_spin_enter(&pmap_segtab_lock); 348 if (__predict_true((stp = pmap_segtab_info.free_segtab) != NULL)) { 349 pmap_segtab_info.free_segtab = stp->seg_seg[0]; 350 stp->seg_seg[0] = NULL; 351 SEGTAB_ADD(nget, 1); 352 found_on_freelist = true; 353 UVMHIST_CALLARGS(pmapsegtabhist, "freelist stp=%#jx", stp, 0, 0, 0); 354 } 355 mutex_spin_exit(&pmap_segtab_lock); 356 357 if (__predict_false(stp == NULL)) { 358 struct vm_page * const stp_pg = pmap_pte_pagealloc(); 359 360 if (__predict_false(stp_pg == NULL)) { 361 /* 362 * XXX What else can we do? Could we deadlock here? 363 */ 364 uvm_wait("segtab"); 365 goto again; 366 } 367 SEGTAB_ADD(npage, 1); 368 const paddr_t stp_pa = VM_PAGE_TO_PHYS(stp_pg); 369 370 stp = (pmap_segtab_t *)PMAP_MAP_POOLPAGE(stp_pa); 371 UVMHIST_CALLARGS(pmapsegtabhist, "new stp=%#jx", stp, 0, 0, 0); 372 const size_t n = NBPG / sizeof(*stp); 373 if (n > 1) { 374 /* 375 * link all the segtabs in this page together 376 */ 377 for (size_t i = 1; i < n - 1; i++) { 378 stp[i].seg_seg[0] = &stp[i+1]; 379 } 380 /* 381 * Now link the new segtabs into the free segtab list. 382 */ 383 mutex_spin_enter(&pmap_segtab_lock); 384 stp[n-1].seg_seg[0] = pmap_segtab_info.free_segtab; 385 pmap_segtab_info.free_segtab = stp + 1; 386 SEGTAB_ADD(nput, n - 1); 387 mutex_spin_exit(&pmap_segtab_lock); 388 } 389 } 390 391 pmap_check_stp(stp, __func__, 392 found_on_freelist ? "from free list" : "allocated"); 393 394 return stp; 395 } 396 397 /* 398 * Allocate the top segment table for the pmap. 399 */ 400 void 401 pmap_segtab_init(pmap_t pmap) 402 { 403 404 pmap->pm_segtab = pmap_segtab_alloc(); 405 } 406 407 /* 408 * Retire the given physical map from service. 409 * Should only be called if the map contains 410 * no valid mappings. 411 */ 412 void 413 pmap_segtab_destroy(pmap_t pmap, pte_callback_t func, uintptr_t flags) 414 { 415 if (pmap->pm_segtab == NULL) 416 return; 417 418 #ifdef _LP64 419 const vsize_t vinc = NBXSEG; 420 #else 421 const vsize_t vinc = NBSEG; 422 #endif 423 pmap_segtab_release(pmap, &pmap->pm_segtab, 424 func == NULL, func, flags, pmap->pm_minaddr, vinc); 425 } 426 427 /* 428 * Make a new pmap (vmspace) active for the given process. 429 */ 430 void 431 pmap_segtab_activate(struct pmap *pm, struct lwp *l) 432 { 433 if (l == curlwp) { 434 struct cpu_info * const ci = l->l_cpu; 435 pmap_md_xtab_activate(pm, l); 436 KASSERT(pm == l->l_proc->p_vmspace->vm_map.pmap); 437 if (pm == pmap_kernel()) { 438 ci->ci_pmap_user_segtab = PMAP_INVALID_SEGTAB_ADDRESS; 439 #ifdef _LP64 440 ci->ci_pmap_user_seg0tab = PMAP_INVALID_SEGTAB_ADDRESS; 441 #endif 442 } else { 443 ci->ci_pmap_user_segtab = pm->pm_segtab; 444 #ifdef _LP64 445 ci->ci_pmap_user_seg0tab = pm->pm_segtab->seg_seg[0]; 446 #endif 447 } 448 } 449 } 450 451 452 void 453 pmap_segtab_deactivate(pmap_t pm) 454 { 455 456 pmap_md_xtab_deactivate(pm); 457 458 curcpu()->ci_pmap_user_segtab = PMAP_INVALID_SEGTAB_ADDRESS; 459 #ifdef _LP64 460 curcpu()->ci_pmap_user_seg0tab = NULL; 461 #endif 462 463 } 464 465 /* 466 * Act on the given range of addresses from the specified map. 467 * 468 * It is assumed that the start and end are properly rounded to 469 * the page size. 470 */ 471 void 472 pmap_pte_process(pmap_t pmap, vaddr_t sva, vaddr_t eva, 473 pte_callback_t callback, uintptr_t flags) 474 { 475 #if 0 476 printf("%s: %p, %"PRIxVADDR", %"PRIxVADDR", %p, %"PRIxPTR"\n", 477 __func__, pmap, sva, eva, callback, flags); 478 #endif 479 while (sva < eva) { 480 vaddr_t lastseg_va = pmap_trunc_seg(sva) + NBSEG; 481 if (lastseg_va == 0 || lastseg_va > eva) 482 lastseg_va = eva; 483 484 /* 485 * If VA belongs to an unallocated segment, 486 * skip to the next segment boundary. 487 */ 488 pt_entry_t * const ptep = pmap_pte_lookup(pmap, sva); 489 if (ptep != NULL) { 490 /* 491 * Callback to deal with the ptes for this segment. 492 */ 493 (*callback)(pmap, sva, lastseg_va, ptep, flags); 494 } 495 /* 496 * In theory we could release pages with no entries, 497 * but that takes more effort than we want here. 498 */ 499 sva = lastseg_va; 500 } 501 } 502 503 /* 504 * Return a pointer for the pte that corresponds to the specified virtual 505 * address (va) in the target physical map, allocating if needed. 506 */ 507 pt_entry_t * 508 pmap_pte_reserve(pmap_t pmap, vaddr_t va, int flags) 509 { 510 pmap_segtab_t *stp = pmap->pm_segtab; 511 pt_entry_t *pte; 512 UVMHIST_FUNC(__func__); 513 514 pte = pmap_pte_lookup(pmap, va); 515 if (__predict_false(pte == NULL)) { 516 #ifdef _LP64 517 pmap_segtab_t ** const stp_p = 518 &stp->seg_seg[(va >> XSEGSHIFT) & (NSEGPG - 1)]; 519 if (__predict_false((stp = *stp_p) == NULL)) { 520 pmap_segtab_t *nstp = pmap_segtab_alloc(); 521 #ifdef MULTIPROCESSOR 522 pmap_segtab_t *ostp = atomic_cas_ptr(stp_p, NULL, nstp); 523 if (__predict_false(ostp != NULL)) { 524 pmap_check_stp(nstp, __func__, "reserve"); 525 pmap_segtab_free(nstp); 526 nstp = ostp; 527 } 528 #else 529 *stp_p = nstp; 530 #endif /* MULTIPROCESSOR */ 531 stp = nstp; 532 } 533 KASSERT(stp == pmap->pm_segtab->seg_seg[(va >> XSEGSHIFT) & (NSEGPG - 1)]); 534 #endif /* _LP64 */ 535 struct vm_page *pg = NULL; 536 #ifdef PMAP_PTP_CACHE 537 mutex_spin_enter(&pmap_segtab_lock); 538 if ((pg = LIST_FIRST(&pmap_segtab_info.ptp_pgflist)) != NULL) { 539 LIST_REMOVE(pg, pageq.list); 540 KASSERT(LIST_FIRST(&pmap_segtab_info.ptp_pgflist) != pg); 541 } 542 mutex_spin_exit(&pmap_segtab_lock); 543 #endif 544 if (pg == NULL) 545 pg = pmap_pte_pagealloc(); 546 if (pg == NULL) { 547 if (flags & PMAP_CANFAIL) 548 return NULL; 549 panic("%s: cannot allocate page table page " 550 "for va %" PRIxVADDR, __func__, va); 551 } 552 553 const paddr_t pa = VM_PAGE_TO_PHYS(pg); 554 pte = (pt_entry_t *)PMAP_MAP_POOLPAGE(pa); 555 pt_entry_t ** const pte_p = 556 &stp->seg_tab[(va >> SEGSHIFT) & (PMAP_SEGTABSIZE - 1)]; 557 #ifdef MULTIPROCESSOR 558 pt_entry_t *opte = atomic_cas_ptr(pte_p, NULL, pte); 559 /* 560 * If another thread allocated the segtab needed for this va 561 * free the page we just allocated. 562 */ 563 if (__predict_false(opte != NULL)) { 564 #ifdef PMAP_PTP_CACHE 565 mutex_spin_enter(&pmap_segtab_lock); 566 LIST_INSERT_HEAD(&pmap_segtab_info.ptp_pgflist, 567 pg, pageq.list); 568 mutex_spin_exit(&pmap_segtab_lock); 569 #else 570 PMAP_UNMAP_POOLPAGE((vaddr_t)pte); 571 uvm_pagefree(pg); 572 #endif 573 pte = opte; 574 } 575 #else 576 *pte_p = pte; 577 #endif 578 KASSERT(pte == stp->seg_tab[(va >> SEGSHIFT) & (PMAP_SEGTABSIZE - 1)]); 579 UVMHIST_CALLARGS(pmapsegtabhist, "pm=%#jx va=%#jx -> tab[%jd]=%jx", 580 (uintptr_t)pmap, (uintptr_t)va, 581 (va >> SEGSHIFT) & (PMAP_SEGTABSIZE - 1), pte); 582 583 pmap_check_ptes(pte, __func__); 584 pte += (va >> PGSHIFT) & (NPTEPG - 1); 585 } 586 587 return pte; 588 } 589
Indexes created Tue Sep 23 14:10:03 GMT 2025