1 /* $NetBSD: xen_pmap.c,v 1.39 2020/09/06 02:18:53 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 1.39 2020/09/06 02:18:53 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> 127 128 #include <x86/pmap_pv.h> 129 130 #include <x86/i82489reg.h> 131 #include <x86/i82489var.h> 132 133 #include <xen/include/public/xen.h> 134 #include <xen/hypervisor.h> 135 #include <xen/xenpmap.h> 136 137 #define COUNT(x) /* nothing */ 138 139 extern pd_entry_t * const normal_pdes[]; 140 141 extern paddr_t pmap_pa_start; /* PA of first physical page for this domain */ 142 extern paddr_t pmap_pa_end; /* PA of last physical page for this domain */ 143 144 int 145 pmap_enter(struct pmap *pmap, vaddr_t va, paddr_t pa, vm_prot_t prot, u_int flags) 146 { 147 paddr_t ma; 148 149 if (__predict_false(pa < pmap_pa_start || pmap_pa_end <= pa)) { 150 ma = pa; /* XXX hack */ 151 } else { 152 ma = xpmap_ptom(pa); 153 } 154 155 return pmap_enter_ma(pmap, va, ma, pa, prot, flags, DOMID_SELF); 156 } 157 158 /* 159 * pmap_kenter_ma: enter a kernel mapping without R/M (pv_entry) tracking 160 * 161 * => no need to lock anything, assume va is already allocated 162 * => should be faster than normal pmap enter function 163 * => we expect a MACHINE address 164 */ 165 166 void 167 pmap_kenter_ma(vaddr_t va, paddr_t ma, vm_prot_t prot, u_int flags) 168 { 169 pt_entry_t *pte, opte, npte; 170 171 if (va < VM_MIN_KERNEL_ADDRESS) 172 pte = vtopte(va); 173 else 174 pte = kvtopte(va); 175 176 npte = ma | ((prot & VM_PROT_WRITE) ? PTE_W : 0) | PTE_P; 177 if (flags & PMAP_NOCACHE) 178 npte |= PTE_PCD; 179 180 if ((cpu_feature[2] & CPUID_NOX) && !(prot & VM_PROT_EXECUTE)) 181 npte |= PTE_NX; 182 183 opte = pmap_pte_testset(pte, npte); /* zap! */ 184 185 if (pmap_valid_entry(opte)) { 186 #if defined(MULTIPROCESSOR) 187 if (__predict_false(x86_mp_online == false)) { 188 pmap_update_pg(va); 189 } else { 190 kpreempt_disable(); 191 pmap_tlb_shootdown(pmap_kernel(), va, opte, 192 TLBSHOOT_KENTER); 193 kpreempt_enable(); 194 } 195 #else 196 /* Don't bother deferring in the single CPU case. */ 197 pmap_update_pg(va); 198 #endif 199 } 200 } 201 202 /* 203 * pmap_extract_ma: extract a MA for the given VA 204 */ 205 206 bool 207 pmap_extract_ma(struct pmap *pmap, vaddr_t va, paddr_t *pap) 208 { 209 pt_entry_t *ptes, pte; 210 pd_entry_t pde; 211 pd_entry_t * const *pdes; 212 struct pmap *pmap2; 213 int lvl; 214 215 if (pmap != pmap_kernel()) { 216 mutex_enter(&pmap->pm_lock); 217 } 218 pmap_map_ptes(pmap, &pmap2, &ptes, &pdes); 219 if (!pmap_pdes_valid(va, pdes, &pde, &lvl)) { 220 pmap_unmap_ptes(pmap, pmap2); 221 if (pmap != pmap_kernel()) { 222 mutex_exit(&pmap->pm_lock); 223 } 224 return false; 225 } 226 227 KASSERT(lvl == 1); 228 pte = ptes[pl1_i(va)]; 229 pmap_unmap_ptes(pmap, pmap2); 230 if (pmap != pmap_kernel()) { 231 mutex_exit(&pmap->pm_lock); 232 } 233 234 if (__predict_true((pte & PTE_P) != 0)) { 235 if (pap != NULL) 236 *pap = (pte & PTE_4KFRAME) | (va & (NBPD_L1 - 1)); 237 return true; 238 } 239 240 return false; 241 } 242 243 /* 244 * Xen pmap's handlers for save/restore 245 */ 246 void 247 pmap_xen_suspend(void) 248 { 249 pmap_unmap_recursive_entries(); 250 251 xpq_flush_queue(); 252 } 253 254 void 255 pmap_xen_resume(void) 256 { 257 pmap_map_recursive_entries(); 258 259 xpq_flush_queue(); 260 } 261 262 /* 263 * NetBSD uses L2 shadow pages to support PAE with Xen. However, Xen does not 264 * handle them correctly during save/restore, leading to incorrect page 265 * tracking and pinning during restore. 266 * For save/restore to succeed, two functions are introduced: 267 * - pmap_map_recursive_entries(), used by resume code to set the recursive 268 * mapping entries to their correct value 269 * - pmap_unmap_recursive_entries(), used by suspend code to clear all 270 * PDIR_SLOT_PTE entries 271 */ 272 void 273 pmap_map_recursive_entries(void) 274 { 275 int i; 276 struct pmap *pm; 277 278 mutex_enter(&pmaps_lock); 279 LIST_FOREACH(pm, &pmaps, pm_list) { 280 for (i = 0; i < PDP_SIZE; i++) { 281 xpq_queue_pte_update( 282 xpmap_ptom(pmap_pdirpa(pm, PDIR_SLOT_PTE + i)), 283 xpmap_ptom((pm)->pm_pdirpa[i]) | PTE_P); 284 } 285 } 286 mutex_exit(&pmaps_lock); 287 288 for (i = 0; i < PDP_SIZE; i++) { 289 xpq_queue_pte_update( 290 xpmap_ptom(pmap_pdirpa(pmap_kernel(), PDIR_SLOT_PTE + i)), 291 xpmap_ptom(pmap_kernel()->pm_pdirpa[i]) | PTE_P); 292 } 293 } 294 295 /* 296 * Unmap recursive entries found in pmaps. Required during Xen 297 * save/restore operations, as Xen does not handle recursive mappings 298 * properly. 299 */ 300 void 301 pmap_unmap_recursive_entries(void) 302 { 303 int i; 304 struct pmap *pm; 305 306 /* 307 * Invalidate pmap_pdp_cache as it contains L2-pinned objects with 308 * recursive entries. 309 * XXX jym@ : find a way to drain per-CPU caches to. pool_cache_inv 310 * does not do that. 311 */ 312 pool_cache_invalidate(&pmap_cache); 313 314 mutex_enter(&pmaps_lock); 315 LIST_FOREACH(pm, &pmaps, pm_list) { 316 for (i = 0; i < PDP_SIZE; i++) { 317 xpq_queue_pte_update( 318 xpmap_ptom(pmap_pdirpa(pm, PDIR_SLOT_PTE + i)), 0); 319 } 320 } 321 mutex_exit(&pmaps_lock); 322 323 /* do it for pmap_kernel() too! */ 324 for (i = 0; i < PDP_SIZE; i++) { 325 xpq_queue_pte_update( 326 xpmap_ptom(pmap_pdirpa(pmap_kernel(), PDIR_SLOT_PTE + i)), 327 0); 328 } 329 } 330 331 static __inline void 332 pmap_kpm_setpte(struct cpu_info *ci, struct pmap *pmap, int index) 333 { 334 KASSERT(mutex_owned(&pmap->pm_lock)); 335 KASSERT(mutex_owned(&ci->ci_kpm_mtx)); 336 if (pmap == pmap_kernel()) { 337 KASSERT(index >= PDIR_SLOT_KERN); 338 } 339 340 #ifdef __x86_64__ 341 xpq_queue_pte_update( 342 xpmap_ptetomach(&ci->ci_kpm_pdir[index]), 343 pmap->pm_pdir[index]); 344 #else 345 xpq_queue_pte_update( 346 xpmap_ptetomach(&ci->ci_kpm_pdir[l2tol2(index)]), 347 pmap->pm_pdir[index]); 348 #endif 349 350 xpq_flush_queue(); 351 } 352 353 /* 354 * Synchronise shadow pdir with the pmap on all cpus on which it is 355 * loaded. 356 */ 357 void 358 xen_kpm_sync(struct pmap *pmap, int index) 359 { 360 CPU_INFO_ITERATOR cii; 361 struct cpu_info *ci; 362 363 KASSERT(pmap != NULL); 364 KASSERT(kpreempt_disabled()); 365 366 pmap_pte_flush(); 367 368 for (CPU_INFO_FOREACH(cii, ci)) { 369 if (ci == NULL) { 370 continue; 371 } 372 cpuid_t cid = cpu_index(ci); 373 if (pmap != pmap_kernel() && 374 !kcpuset_isset(pmap->pm_xen_ptp_cpus, cid)) 375 continue; 376 377 /* take the lock and check again */ 378 mutex_enter(&ci->ci_kpm_mtx); 379 if (pmap == pmap_kernel() || 380 kcpuset_isset(pmap->pm_xen_ptp_cpus, cid)) { 381 pmap_kpm_setpte(ci, pmap, index); 382 } 383 mutex_exit(&ci->ci_kpm_mtx); 384 } 385 } 386