1 /* $NetBSD: xen_pmap.c,v 1.40 2022/08/20 23:48:51 riastradh Exp $ */ 2 3 /* 4 * Copyright (c) 2007 Manuel Bouyer. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 /* 28 * Copyright (c) 2006 Mathieu Ropert <mro@adviseo.fr> 29 * 30 * Permission to use, copy, modify, and distribute this software for any 31 * purpose with or without fee is hereby granted, provided that the above 32 * copyright notice and this permission notice appear in all copies. 33 * 34 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 35 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 36 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 37 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 38 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 39 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 40 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 41 */ 42 43 /* 44 * Copyright (c) 1997 Charles D. Cranor and Washington University. 45 * All rights reserved. 46 * 47 * Redistribution and use in source and binary forms, with or without 48 * modification, are permitted provided that the following conditions 49 * are met: 50 * 1. Redistributions of source code must retain the above copyright 51 * notice, this list of conditions and the following disclaimer. 52 * 2. Redistributions in binary form must reproduce the above copyright 53 * notice, this list of conditions and the following disclaimer in the 54 * documentation and/or other materials provided with the distribution. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 57 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 58 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 59 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 60 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 61 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 62 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 63 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 64 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 65 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 66 */ 67 68 /* 69 * Copyright 2001 (c) Wasabi Systems, Inc. 70 * All rights reserved. 71 * 72 * Written by Frank van der Linden for Wasabi Systems, Inc. 73 * 74 * Redistribution and use in source and binary forms, with or without 75 * modification, are permitted provided that the following conditions 76 * are met: 77 * 1. Redistributions of source code must retain the above copyright 78 * notice, this list of conditions and the following disclaimer. 79 * 2. Redistributions in binary form must reproduce the above copyright 80 * notice, this list of conditions and the following disclaimer in the 81 * documentation and/or other materials provided with the distribution. 82 * 3. All advertising materials mentioning features or use of this software 83 * must display the following acknowledgement: 84 * This product includes software developed for the NetBSD Project by 85 * Wasabi Systems, Inc. 86 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 87 * or promote products derived from this software without specific prior 88 * written permission. 89 * 90 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 91 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 92 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 93 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 94 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 95 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 96 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 97 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 98 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 99 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 100 * POSSIBILITY OF SUCH DAMAGE. 101 */ 102 103 #include <sys/cdefs.h> 104 __KERNEL_RCSID(0, "$NetBSD: xen_pmap.c,v 1.40 2022/08/20 23:48:51 riastradh Exp $"); 105 106 #include "opt_lockdebug.h" 107 #include "opt_multiprocessor.h" 108 #include "opt_xen.h" 109 110 #include <sys/param.h> 111 #include <sys/systm.h> 112 #include <sys/proc.h> 113 #include <sys/pool.h> 114 #include <sys/kernel.h> 115 #include <sys/atomic.h> 116 #include <sys/cpu.h> 117 #include <sys/intr.h> 118 119 #include <uvm/uvm.h> 120 121 #include <dev/isa/isareg.h> 122 123 #include <machine/specialreg.h> 124 #include <machine/gdt.h> 125 #include <machine/isa_machdep.h> 126 #include <machine/cpuvar.h> 127 #include <machine/pmap_private.h> 128 129 #include <x86/pmap_pv.h> 130 131 #include <x86/i82489reg.h> 132 #include <x86/i82489var.h> 133 134 #include <xen/include/public/xen.h> 135 #include <xen/hypervisor.h> 136 #include <xen/xenpmap.h> 137 138 #define COUNT(x) /* nothing */ 139 140 extern pd_entry_t * const normal_pdes[]; 141 142 extern paddr_t pmap_pa_start; /* PA of first physical page for this domain */ 143 extern paddr_t pmap_pa_end; /* PA of last physical page for this domain */ 144 145 int 146 pmap_enter(struct pmap *pmap, vaddr_t va, paddr_t pa, vm_prot_t prot, u_int flags) 147 { 148 paddr_t ma; 149 150 if (__predict_false(pa < pmap_pa_start || pmap_pa_end <= pa)) { 151 ma = pa; /* XXX hack */ 152 } else { 153 ma = xpmap_ptom(pa); 154 } 155 156 return pmap_enter_ma(pmap, va, ma, pa, prot, flags, DOMID_SELF); 157 } 158 159 /* 160 * pmap_kenter_ma: enter a kernel mapping without R/M (pv_entry) tracking 161 * 162 * => no need to lock anything, assume va is already allocated 163 * => should be faster than normal pmap enter function 164 * => we expect a MACHINE address 165 */ 166 167 void 168 pmap_kenter_ma(vaddr_t va, paddr_t ma, vm_prot_t prot, u_int flags) 169 { 170 pt_entry_t *pte, opte, npte; 171 172 if (va < VM_MIN_KERNEL_ADDRESS) 173 pte = vtopte(va); 174 else 175 pte = kvtopte(va); 176 177 npte = ma | ((prot & VM_PROT_WRITE) ? PTE_W : 0) | PTE_P; 178 if (flags & PMAP_NOCACHE) 179 npte |= PTE_PCD; 180 181 if ((cpu_feature[2] & CPUID_NOX) && !(prot & VM_PROT_EXECUTE)) 182 npte |= PTE_NX; 183 184 opte = pmap_pte_testset(pte, npte); /* zap! */ 185 186 if (pmap_valid_entry(opte)) { 187 #if defined(MULTIPROCESSOR) 188 if (__predict_false(x86_mp_online == false)) { 189 pmap_update_pg(va); 190 } else { 191 kpreempt_disable(); 192 pmap_tlb_shootdown(pmap_kernel(), va, opte, 193 TLBSHOOT_KENTER); 194 kpreempt_enable(); 195 } 196 #else 197 /* Don't bother deferring in the single CPU case. */ 198 pmap_update_pg(va); 199 #endif 200 } 201 } 202 203 /* 204 * pmap_extract_ma: extract a MA for the given VA 205 */ 206 207 bool 208 pmap_extract_ma(struct pmap *pmap, vaddr_t va, paddr_t *pap) 209 { 210 pt_entry_t *ptes, pte; 211 pd_entry_t pde; 212 pd_entry_t * const *pdes; 213 struct pmap *pmap2; 214 int lvl; 215 216 if (pmap != pmap_kernel()) { 217 mutex_enter(&pmap->pm_lock); 218 } 219 pmap_map_ptes(pmap, &pmap2, &ptes, &pdes); 220 if (!pmap_pdes_valid(va, pdes, &pde, &lvl)) { 221 pmap_unmap_ptes(pmap, pmap2); 222 if (pmap != pmap_kernel()) { 223 mutex_exit(&pmap->pm_lock); 224 } 225 return false; 226 } 227 228 KASSERT(lvl == 1); 229 pte = ptes[pl1_i(va)]; 230 pmap_unmap_ptes(pmap, pmap2); 231 if (pmap != pmap_kernel()) { 232 mutex_exit(&pmap->pm_lock); 233 } 234 235 if (__predict_true((pte & PTE_P) != 0)) { 236 if (pap != NULL) 237 *pap = (pte & PTE_4KFRAME) | (va & (NBPD_L1 - 1)); 238 return true; 239 } 240 241 return false; 242 } 243 244 /* 245 * Xen pmap's handlers for save/restore 246 */ 247 void 248 pmap_xen_suspend(void) 249 { 250 pmap_unmap_recursive_entries(); 251 252 xpq_flush_queue(); 253 } 254 255 void 256 pmap_xen_resume(void) 257 { 258 pmap_map_recursive_entries(); 259 260 xpq_flush_queue(); 261 } 262 263 /* 264 * NetBSD uses L2 shadow pages to support PAE with Xen. However, Xen does not 265 * handle them correctly during save/restore, leading to incorrect page 266 * tracking and pinning during restore. 267 * For save/restore to succeed, two functions are introduced: 268 * - pmap_map_recursive_entries(), used by resume code to set the recursive 269 * mapping entries to their correct value 270 * - pmap_unmap_recursive_entries(), used by suspend code to clear all 271 * PDIR_SLOT_PTE entries 272 */ 273 void 274 pmap_map_recursive_entries(void) 275 { 276 int i; 277 struct pmap *pm; 278 279 mutex_enter(&pmaps_lock); 280 LIST_FOREACH(pm, &pmaps, pm_list) { 281 for (i = 0; i < PDP_SIZE; i++) { 282 xpq_queue_pte_update( 283 xpmap_ptom(pmap_pdirpa(pm, PDIR_SLOT_PTE + i)), 284 xpmap_ptom((pm)->pm_pdirpa[i]) | PTE_P); 285 } 286 } 287 mutex_exit(&pmaps_lock); 288 289 for (i = 0; i < PDP_SIZE; i++) { 290 xpq_queue_pte_update( 291 xpmap_ptom(pmap_pdirpa(pmap_kernel(), PDIR_SLOT_PTE + i)), 292 xpmap_ptom(pmap_kernel()->pm_pdirpa[i]) | PTE_P); 293 } 294 } 295 296 /* 297 * Unmap recursive entries found in pmaps. Required during Xen 298 * save/restore operations, as Xen does not handle recursive mappings 299 * properly. 300 */ 301 void 302 pmap_unmap_recursive_entries(void) 303 { 304 int i; 305 struct pmap *pm; 306 307 /* 308 * Invalidate pmap_pdp_cache as it contains L2-pinned objects with 309 * recursive entries. 310 * XXX jym@ : find a way to drain per-CPU caches to. pool_cache_inv 311 * does not do that. 312 */ 313 pool_cache_invalidate(&pmap_cache); 314 315 mutex_enter(&pmaps_lock); 316 LIST_FOREACH(pm, &pmaps, pm_list) { 317 for (i = 0; i < PDP_SIZE; i++) { 318 xpq_queue_pte_update( 319 xpmap_ptom(pmap_pdirpa(pm, PDIR_SLOT_PTE + i)), 0); 320 } 321 } 322 mutex_exit(&pmaps_lock); 323 324 /* do it for pmap_kernel() too! */ 325 for (i = 0; i < PDP_SIZE; i++) { 326 xpq_queue_pte_update( 327 xpmap_ptom(pmap_pdirpa(pmap_kernel(), PDIR_SLOT_PTE + i)), 328 0); 329 } 330 } 331 332 static __inline void 333 pmap_kpm_setpte(struct cpu_info *ci, struct pmap *pmap, int index) 334 { 335 KASSERT(mutex_owned(&pmap->pm_lock)); 336 KASSERT(mutex_owned(&ci->ci_kpm_mtx)); 337 if (pmap == pmap_kernel()) { 338 KASSERT(index >= PDIR_SLOT_KERN); 339 } 340 341 #ifdef __x86_64__ 342 xpq_queue_pte_update( 343 xpmap_ptetomach(&ci->ci_kpm_pdir[index]), 344 pmap->pm_pdir[index]); 345 #else 346 xpq_queue_pte_update( 347 xpmap_ptetomach(&ci->ci_kpm_pdir[l2tol2(index)]), 348 pmap->pm_pdir[index]); 349 #endif 350 351 xpq_flush_queue(); 352 } 353 354 /* 355 * Synchronise shadow pdir with the pmap on all cpus on which it is 356 * loaded. 357 */ 358 void 359 xen_kpm_sync(struct pmap *pmap, int index) 360 { 361 CPU_INFO_ITERATOR cii; 362 struct cpu_info *ci; 363 364 KASSERT(pmap != NULL); 365 KASSERT(kpreempt_disabled()); 366 367 pmap_pte_flush(); 368 369 for (CPU_INFO_FOREACH(cii, ci)) { 370 if (ci == NULL) { 371 continue; 372 } 373 cpuid_t cid = cpu_index(ci); 374 if (pmap != pmap_kernel() && 375 !kcpuset_isset(pmap->pm_xen_ptp_cpus, cid)) 376 continue; 377 378 /* take the lock and check again */ 379 mutex_enter(&ci->ci_kpm_mtx); 380 if (pmap == pmap_kernel() || 381 kcpuset_isset(pmap->pm_xen_ptp_cpus, cid)) { 382 pmap_kpm_setpte(ci, pmap, index); 383 } 384 mutex_exit(&ci->ci_kpm_mtx); 385 } 386 } 387