arch/mips/kvm/trap_emul.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * KVM/MIPS: Deliver/Emulate exceptions to the guest kernel
   7  *
   8  * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
   9  * Authors: Sanjay Lal <sanjayl@kymasys.com>
  10  */
  11
  12 #include <linux/errno.h>
  13 #include <linux/err.h>
  14 #include <linux/module.h>
  15 #include <linux/vmalloc.h>
  16
  17 #include <linux/kvm_host.h>
  18
  19 #include "interrupt.h"
  20
  21 static gpa_t kvm_trap_emul_gva_to_gpa_cb(gva_t gva)
  22 {
  23         gpa_t gpa;
  24         uint32_t kseg = KSEGX(gva);
  25
  26         if ((kseg == CKSEG0) || (kseg == CKSEG1))
  27                 gpa = CPHYSADDR(gva);
  28         else {
  29                 kvm_err("%s: cannot find GPA for GVA: %#lx\n", __func__, gva);
  30                 kvm_mips_dump_host_tlbs();
  31                 gpa = KVM_INVALID_ADDR;
  32         }
  33
  34         kvm_debug("%s: gva %#lx, gpa: %#llx\n", __func__, gva, gpa);
  35
  36         return gpa;
  37 }
  38
  39 static int kvm_trap_emul_handle_cop_unusable(struct kvm_vcpu *vcpu)
  40 {
  41         struct mips_coproc *cop0 = vcpu->arch.cop0;
  42         struct kvm_run *run = vcpu->run;
  43         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
  44         unsigned long cause = vcpu->arch.host_cp0_cause;
  45         enum emulation_result er = EMULATE_DONE;
  46         int ret = RESUME_GUEST;
  47
  48         if (((cause & CAUSEF_CE) >> CAUSEB_CE) == 1) {
  49                 /* FPU Unusable */
  50                 if (!kvm_mips_guest_has_fpu(&vcpu->arch) ||
  51                     (kvm_read_c0_guest_status(cop0) & ST0_CU1) == 0) {
  52                         /*
  53                          * Unusable/no FPU in guest:
  54                          * deliver guest COP1 Unusable Exception
  55                          */
  56                         er = kvm_mips_emulate_fpu_exc(cause, opc, run, vcpu);
  57                 } else {
  58                         /* Restore FPU state */
  59                         kvm_own_fpu(vcpu);
  60                         er = EMULATE_DONE;
  61                 }
  62         } else {
  63                 er = kvm_mips_emulate_inst(cause, opc, run, vcpu);
  64         }
  65
  66         switch (er) {
  67         case EMULATE_DONE:
  68                 ret = RESUME_GUEST;
  69                 break;
  70
  71         case EMULATE_FAIL:
  72                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
  73                 ret = RESUME_HOST;
  74                 break;
  75
  76         case EMULATE_WAIT:
  77                 run->exit_reason = KVM_EXIT_INTR;
  78                 ret = RESUME_HOST;
  79                 break;
  80
  81         default:
  82                 BUG();
  83         }
  84         return ret;
  85 }
  86
  87 static int kvm_trap_emul_handle_tlb_mod(struct kvm_vcpu *vcpu)
  88 {
  89         struct kvm_run *run = vcpu->run;
  90         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
  91         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
  92         unsigned long cause = vcpu->arch.host_cp0_cause;
  93         enum emulation_result er = EMULATE_DONE;
  94         int ret = RESUME_GUEST;
  95
  96         if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
  97             || KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
  98                 kvm_debug("USER/KSEG23 ADDR TLB MOD fault: cause %#lx, PC: %p, BadVaddr: %#lx\n",
  99                           cause, opc, badvaddr);
 100                 er = kvm_mips_handle_tlbmod(cause, opc, run, vcpu);
 101
 102                 if (er == EMULATE_DONE)
 103                         ret = RESUME_GUEST;
 104                 else {
 105                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 106                         ret = RESUME_HOST;
 107                 }
 108         } else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
 109                 /*
 110                  * XXXKYMA: The guest kernel does not expect to get this fault
 111                  * when we are not using HIGHMEM. Need to address this in a
 112                  * HIGHMEM kernel
 113                  */
 114                 kvm_err("TLB MOD fault not handled, cause %#lx, PC: %p, BadVaddr: %#lx\n",
 115                         cause, opc, badvaddr);
 116                 kvm_mips_dump_host_tlbs();
 117                 kvm_arch_vcpu_dump_regs(vcpu);
 118                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 119                 ret = RESUME_HOST;
 120         } else {
 121                 kvm_err("Illegal TLB Mod fault address , cause %#lx, PC: %p, BadVaddr: %#lx\n",
 122                         cause, opc, badvaddr);
 123                 kvm_mips_dump_host_tlbs();
 124                 kvm_arch_vcpu_dump_regs(vcpu);
 125                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 126                 ret = RESUME_HOST;
 127         }
 128         return ret;
 129 }
 130
 131 static int kvm_trap_emul_handle_tlb_st_miss(struct kvm_vcpu *vcpu)
 132 {
 133         struct kvm_run *run = vcpu->run;
 134         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 135         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
 136         unsigned long cause = vcpu->arch.host_cp0_cause;
 137         enum emulation_result er = EMULATE_DONE;
 138         int ret = RESUME_GUEST;
 139
 140         if (((badvaddr & PAGE_MASK) == KVM_GUEST_COMMPAGE_ADDR)
 141             && KVM_GUEST_KERNEL_MODE(vcpu)) {
 142                 if (kvm_mips_handle_commpage_tlb_fault(badvaddr, vcpu) < 0) {
 143                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 144                         ret = RESUME_HOST;
 145                 }
 146         } else if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
 147                    || KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
 148                 kvm_debug("USER ADDR TLB LD fault: cause %#lx, PC: %p, BadVaddr: %#lx\n",
 149                           cause, opc, badvaddr);
 150                 er = kvm_mips_handle_tlbmiss(cause, opc, run, vcpu);
 151                 if (er == EMULATE_DONE)
 152                         ret = RESUME_GUEST;
 153                 else {
 154                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 155                         ret = RESUME_HOST;
 156                 }
 157         } else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
 158                 /*
 159                  * All KSEG0 faults are handled by KVM, as the guest kernel does
 160                  * not expect to ever get them
 161                  */
 162                 if (kvm_mips_handle_kseg0_tlb_fault
 163                     (vcpu->arch.host_cp0_badvaddr, vcpu) < 0) {
 164                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 165                         ret = RESUME_HOST;
 166                 }
 167         } else {
 168                 kvm_err("Illegal TLB LD fault address , cause %#lx, PC: %p, BadVaddr: %#lx\n",
 169                         cause, opc, badvaddr);
 170                 kvm_mips_dump_host_tlbs();
 171                 kvm_arch_vcpu_dump_regs(vcpu);
 172                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 173                 ret = RESUME_HOST;
 174         }
 175         return ret;
 176 }
 177
 178 static int kvm_trap_emul_handle_tlb_ld_miss(struct kvm_vcpu *vcpu)
 179 {
 180         struct kvm_run *run = vcpu->run;
 181         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 182         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
 183         unsigned long cause = vcpu->arch.host_cp0_cause;
 184         enum emulation_result er = EMULATE_DONE;
 185         int ret = RESUME_GUEST;
 186
 187         if (((badvaddr & PAGE_MASK) == KVM_GUEST_COMMPAGE_ADDR)
 188             && KVM_GUEST_KERNEL_MODE(vcpu)) {
 189                 if (kvm_mips_handle_commpage_tlb_fault(badvaddr, vcpu) < 0) {
 190                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 191                         ret = RESUME_HOST;
 192                 }
 193         } else if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
 194                    || KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
 195                 kvm_debug("USER ADDR TLB ST fault: PC: %#lx, BadVaddr: %#lx\n",
 196                           vcpu->arch.pc, badvaddr);
 197
 198                 /*
 199                  * User Address (UA) fault, this could happen if
 200                  * (1) TLB entry not present/valid in both Guest and shadow host
 201                  *     TLBs, in this case we pass on the fault to the guest
 202                  *     kernel and let it handle it.
 203                  * (2) TLB entry is present in the Guest TLB but not in the
 204                  *     shadow, in this case we inject the TLB from the Guest TLB
 205                  *     into the shadow host TLB
 206                  */
 207
 208                 er = kvm_mips_handle_tlbmiss(cause, opc, run, vcpu);
 209                 if (er == EMULATE_DONE)
 210                         ret = RESUME_GUEST;
 211                 else {
 212                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 213                         ret = RESUME_HOST;
 214                 }
 215         } else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
 216                 if (kvm_mips_handle_kseg0_tlb_fault
 217                     (vcpu->arch.host_cp0_badvaddr, vcpu) < 0) {
 218                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 219                         ret = RESUME_HOST;
 220                 }
 221         } else {
 222                 kvm_err("Illegal TLB ST fault address , cause %#lx, PC: %p, BadVaddr: %#lx\n",
 223                         cause, opc, badvaddr);
 224                 kvm_mips_dump_host_tlbs();
 225                 kvm_arch_vcpu_dump_regs(vcpu);
 226                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 227                 ret = RESUME_HOST;
 228         }
 229         return ret;
 230 }
 231
 232 static int kvm_trap_emul_handle_addr_err_st(struct kvm_vcpu *vcpu)
 233 {
 234         struct kvm_run *run = vcpu->run;
 235         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 236         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
 237         unsigned long cause = vcpu->arch.host_cp0_cause;
 238         enum emulation_result er = EMULATE_DONE;
 239         int ret = RESUME_GUEST;
 240
 241         if (KVM_GUEST_KERNEL_MODE(vcpu)
 242             && (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1)) {
 243                 kvm_debug("Emulate Store to MMIO space\n");
 244                 er = kvm_mips_emulate_inst(cause, opc, run, vcpu);
 245                 if (er == EMULATE_FAIL) {
 246                         kvm_err("Emulate Store to MMIO space failed\n");
 247                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 248                         ret = RESUME_HOST;
 249                 } else {
 250                         run->exit_reason = KVM_EXIT_MMIO;
 251                         ret = RESUME_HOST;
 252                 }
 253         } else {
 254                 kvm_err("Address Error (STORE): cause %#lx, PC: %p, BadVaddr: %#lx\n",
 255                         cause, opc, badvaddr);
 256                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 257                 ret = RESUME_HOST;
 258         }
 259         return ret;
 260 }
 261
 262 static int kvm_trap_emul_handle_addr_err_ld(struct kvm_vcpu *vcpu)
 263 {
 264         struct kvm_run *run = vcpu->run;
 265         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 266         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
 267         unsigned long cause = vcpu->arch.host_cp0_cause;
 268         enum emulation_result er = EMULATE_DONE;
 269         int ret = RESUME_GUEST;
 270
 271         if (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1) {
 272                 kvm_debug("Emulate Load from MMIO space @ %#lx\n", badvaddr);
 273                 er = kvm_mips_emulate_inst(cause, opc, run, vcpu);
 274                 if (er == EMULATE_FAIL) {
 275                         kvm_err("Emulate Load from MMIO space failed\n");
 276                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 277                         ret = RESUME_HOST;
 278                 } else {
 279                         run->exit_reason = KVM_EXIT_MMIO;
 280                         ret = RESUME_HOST;
 281                 }
 282         } else {
 283                 kvm_err("Address Error (LOAD): cause %#lx, PC: %p, BadVaddr: %#lx\n",
 284                         cause, opc, badvaddr);
 285                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 286                 ret = RESUME_HOST;
 287                 er = EMULATE_FAIL;
 288         }
 289         return ret;
 290 }
 291
 292 static int kvm_trap_emul_handle_syscall(struct kvm_vcpu *vcpu)
 293 {
 294         struct kvm_run *run = vcpu->run;
 295         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 296         unsigned long cause = vcpu->arch.host_cp0_cause;
 297         enum emulation_result er = EMULATE_DONE;
 298         int ret = RESUME_GUEST;
 299
 300         er = kvm_mips_emulate_syscall(cause, opc, run, vcpu);
 301         if (er == EMULATE_DONE)
 302                 ret = RESUME_GUEST;
 303         else {
 304                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 305                 ret = RESUME_HOST;
 306         }
 307         return ret;
 308 }
 309
 310 static int kvm_trap_emul_handle_res_inst(struct kvm_vcpu *vcpu)
 311 {
 312         struct kvm_run *run = vcpu->run;
 313         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 314         unsigned long cause = vcpu->arch.host_cp0_cause;
 315         enum emulation_result er = EMULATE_DONE;
 316         int ret = RESUME_GUEST;
 317
 318         er = kvm_mips_handle_ri(cause, opc, run, vcpu);
 319         if (er == EMULATE_DONE)
 320                 ret = RESUME_GUEST;
 321         else {
 322                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 323                 ret = RESUME_HOST;
 324         }
 325         return ret;
 326 }
 327
 328 static int kvm_trap_emul_handle_break(struct kvm_vcpu *vcpu)
 329 {
 330         struct kvm_run *run = vcpu->run;
 331         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 332         unsigned long cause = vcpu->arch.host_cp0_cause;
 333         enum emulation_result er = EMULATE_DONE;
 334         int ret = RESUME_GUEST;
 335
 336         er = kvm_mips_emulate_bp_exc(cause, opc, run, vcpu);
 337         if (er == EMULATE_DONE)
 338                 ret = RESUME_GUEST;
 339         else {
 340                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 341                 ret = RESUME_HOST;
 342         }
 343         return ret;
 344 }
 345
 346 static int kvm_trap_emul_handle_trap(struct kvm_vcpu *vcpu)
 347 {
 348         struct kvm_run *run = vcpu->run;
 349         uint32_t __user *opc = (uint32_t __user *)vcpu->arch.pc;
 350         unsigned long cause = vcpu->arch.host_cp0_cause;
 351         enum emulation_result er = EMULATE_DONE;
 352         int ret = RESUME_GUEST;
 353
 354         er = kvm_mips_emulate_trap_exc(cause, opc, run, vcpu);
 355         if (er == EMULATE_DONE) {
 356                 ret = RESUME_GUEST;
 357         } else {
 358                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 359                 ret = RESUME_HOST;
 360         }
 361         return ret;
 362 }
 363
 364 static int kvm_trap_emul_handle_msa_fpe(struct kvm_vcpu *vcpu)
 365 {
 366         struct kvm_run *run = vcpu->run;
 367         uint32_t __user *opc = (uint32_t __user *)vcpu->arch.pc;
 368         unsigned long cause = vcpu->arch.host_cp0_cause;
 369         enum emulation_result er = EMULATE_DONE;
 370         int ret = RESUME_GUEST;
 371
 372         er = kvm_mips_emulate_msafpe_exc(cause, opc, run, vcpu);
 373         if (er == EMULATE_DONE) {
 374                 ret = RESUME_GUEST;
 375         } else {
 376                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 377                 ret = RESUME_HOST;
 378         }
 379         return ret;
 380 }
 381
 382 static int kvm_trap_emul_handle_fpe(struct kvm_vcpu *vcpu)
 383 {
 384         struct kvm_run *run = vcpu->run;
 385         uint32_t __user *opc = (uint32_t __user *)vcpu->arch.pc;
 386         unsigned long cause = vcpu->arch.host_cp0_cause;
 387         enum emulation_result er = EMULATE_DONE;
 388         int ret = RESUME_GUEST;
 389
 390         er = kvm_mips_emulate_fpe_exc(cause, opc, run, vcpu);
 391         if (er == EMULATE_DONE) {
 392                 ret = RESUME_GUEST;
 393         } else {
 394                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 395                 ret = RESUME_HOST;
 396         }
 397         return ret;
 398 }
 399
 400 /**
 401  * kvm_trap_emul_handle_msa_disabled() - Guest used MSA while disabled in root.
 402  * @vcpu:       Virtual CPU context.
 403  *
 404  * Handle when the guest attempts to use MSA when it is disabled.
 405  */
 406 static int kvm_trap_emul_handle_msa_disabled(struct kvm_vcpu *vcpu)
 407 {
 408         struct mips_coproc *cop0 = vcpu->arch.cop0;
 409         struct kvm_run *run = vcpu->run;
 410         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 411         unsigned long cause = vcpu->arch.host_cp0_cause;
 412         enum emulation_result er = EMULATE_DONE;
 413         int ret = RESUME_GUEST;
 414
 415         if (!kvm_mips_guest_has_msa(&vcpu->arch) ||
 416             (kvm_read_c0_guest_status(cop0) & (ST0_CU1 | ST0_FR)) == ST0_CU1) {
 417                 /*
 418                  * No MSA in guest, or FPU enabled and not in FR=1 mode,
 419                  * guest reserved instruction exception
 420                  */
 421                 er = kvm_mips_emulate_ri_exc(cause, opc, run, vcpu);
 422         } else if (!(kvm_read_c0_guest_config5(cop0) & MIPS_CONF5_MSAEN)) {
 423                 /* MSA disabled by guest, guest MSA disabled exception */
 424                 er = kvm_mips_emulate_msadis_exc(cause, opc, run, vcpu);
 425         } else {
 426                 /* Restore MSA/FPU state */
 427                 kvm_own_msa(vcpu);
 428                 er = EMULATE_DONE;
 429         }
 430
 431         switch (er) {
 432         case EMULATE_DONE:
 433                 ret = RESUME_GUEST;
 434                 break;
 435
 436         case EMULATE_FAIL:
 437                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 438                 ret = RESUME_HOST;
 439                 break;
 440
 441         default:
 442                 BUG();
 443         }
 444         return ret;
 445 }
 446
 447 static int kvm_trap_emul_vm_init(struct kvm *kvm)
 448 {
 449         return 0;
 450 }
 451
 452 static int kvm_trap_emul_vcpu_init(struct kvm_vcpu *vcpu)
 453 {
 454         return 0;
 455 }
 456
 457 static int kvm_trap_emul_vcpu_setup(struct kvm_vcpu *vcpu)
 458 {
 459         struct mips_coproc *cop0 = vcpu->arch.cop0;
 460         uint32_t config1;
 461         int vcpu_id = vcpu->vcpu_id;
 462
 463         /*
 464          * Arch specific stuff, set up config registers properly so that the
 465          * guest will come up as expected, for now we simulate a MIPS 24kc
 466          */
 467         kvm_write_c0_guest_prid(cop0, 0x00019300);
 468         /* Have config1, Cacheable, noncoherent, write-back, write allocate */
 469         kvm_write_c0_guest_config(cop0, MIPS_CONF_M | (0x3 << CP0C0_K0) |
 470                                   (0x1 << CP0C0_AR) |
 471                                   (MMU_TYPE_R4000 << CP0C0_MT));
 472
 473         /* Read the cache characteristics from the host Config1 Register */
 474         config1 = (read_c0_config1() & ~0x7f);
 475
 476         /* Set up MMU size */
 477         config1 &= ~(0x3f << 25);
 478         config1 |= ((KVM_MIPS_GUEST_TLB_SIZE - 1) << 25);
 479
 480         /* We unset some bits that we aren't emulating */
 481         config1 &=
 482             ~((1 << CP0C1_C2) | (1 << CP0C1_MD) | (1 << CP0C1_PC) |
 483               (1 << CP0C1_WR) | (1 << CP0C1_CA));
 484         kvm_write_c0_guest_config1(cop0, config1);
 485
 486         /* Have config3, no tertiary/secondary caches implemented */
 487         kvm_write_c0_guest_config2(cop0, MIPS_CONF_M);
 488         /* MIPS_CONF_M | (read_c0_config2() & 0xfff) */
 489
 490         /* Have config4, UserLocal */
 491         kvm_write_c0_guest_config3(cop0, MIPS_CONF_M | MIPS_CONF3_ULRI);
 492
 493         /* Have config5 */
 494         kvm_write_c0_guest_config4(cop0, MIPS_CONF_M);
 495
 496         /* No config6 */
 497         kvm_write_c0_guest_config5(cop0, 0);
 498
 499         /* Set Wait IE/IXMT Ignore in Config7, IAR, AR */
 500         kvm_write_c0_guest_config7(cop0, (MIPS_CONF7_WII) | (1 << 10));
 501
 502         /*
 503          * Setup IntCtl defaults, compatibilty mode for timer interrupts (HW5)
 504          */
 505         kvm_write_c0_guest_intctl(cop0, 0xFC000000);
 506
 507         /* Put in vcpu id as CPUNum into Ebase Reg to handle SMP Guests */
 508         kvm_write_c0_guest_ebase(cop0, KVM_GUEST_KSEG0 | (vcpu_id & 0xFF));
 509
 510         return 0;
 511 }
 512
 513 static int kvm_trap_emul_get_one_reg(struct kvm_vcpu *vcpu,
 514                                      const struct kvm_one_reg *reg,
 515                                      s64 *v)
 516 {
 517         switch (reg->id) {
 518         case KVM_REG_MIPS_CP0_COUNT:
 519                 *v = kvm_mips_read_count(vcpu);
 520                 break;
 521         case KVM_REG_MIPS_COUNT_CTL:
 522                 *v = vcpu->arch.count_ctl;
 523                 break;
 524         case KVM_REG_MIPS_COUNT_RESUME:
 525                 *v = ktime_to_ns(vcpu->arch.count_resume);
 526                 break;
 527         case KVM_REG_MIPS_COUNT_HZ:
 528                 *v = vcpu->arch.count_hz;
 529                 break;
 530         default:
 531                 return -EINVAL;
 532         }
 533         return 0;
 534 }
 535
 536 static int kvm_trap_emul_set_one_reg(struct kvm_vcpu *vcpu,
 537                                      const struct kvm_one_reg *reg,
 538                                      s64 v)
 539 {
 540         struct mips_coproc *cop0 = vcpu->arch.cop0;
 541         int ret = 0;
 542         unsigned int cur, change;
 543
 544         switch (reg->id) {
 545         case KVM_REG_MIPS_CP0_COUNT:
 546                 kvm_mips_write_count(vcpu, v);
 547                 break;
 548         case KVM_REG_MIPS_CP0_COMPARE:
 549                 kvm_mips_write_compare(vcpu, v);
 550                 break;
 551         case KVM_REG_MIPS_CP0_CAUSE:
 552                 /*
 553                  * If the timer is stopped or started (DC bit) it must look
 554                  * atomic with changes to the interrupt pending bits (TI, IRQ5).
 555                  * A timer interrupt should not happen in between.
 556                  */
 557                 if ((kvm_read_c0_guest_cause(cop0) ^ v) & CAUSEF_DC) {
 558                         if (v & CAUSEF_DC) {
 559                                 /* disable timer first */
 560                                 kvm_mips_count_disable_cause(vcpu);
 561                                 kvm_change_c0_guest_cause(cop0, ~CAUSEF_DC, v);
 562                         } else {
 563                                 /* enable timer last */
 564                                 kvm_change_c0_guest_cause(cop0, ~CAUSEF_DC, v);
 565                                 kvm_mips_count_enable_cause(vcpu);
 566                         }
 567                 } else {
 568                         kvm_write_c0_guest_cause(cop0, v);
 569                 }
 570                 break;
 571         case KVM_REG_MIPS_CP0_CONFIG:
 572                 /* read-only for now */
 573                 break;
 574         case KVM_REG_MIPS_CP0_CONFIG1:
 575                 cur = kvm_read_c0_guest_config1(cop0);
 576                 change = (cur ^ v) & kvm_mips_config1_wrmask(vcpu);
 577                 if (change) {
 578                         v = cur ^ change;
 579                         kvm_write_c0_guest_config1(cop0, v);
 580                 }
 581                 break;
 582         case KVM_REG_MIPS_CP0_CONFIG2:
 583                 /* read-only for now */
 584                 break;
 585         case KVM_REG_MIPS_CP0_CONFIG3:
 586                 cur = kvm_read_c0_guest_config3(cop0);
 587                 change = (cur ^ v) & kvm_mips_config3_wrmask(vcpu);
 588                 if (change) {
 589                         v = cur ^ change;
 590                         kvm_write_c0_guest_config3(cop0, v);
 591                 }
 592                 break;
 593         case KVM_REG_MIPS_CP0_CONFIG4:
 594                 cur = kvm_read_c0_guest_config4(cop0);
 595                 change = (cur ^ v) & kvm_mips_config4_wrmask(vcpu);
 596                 if (change) {
 597                         v = cur ^ change;
 598                         kvm_write_c0_guest_config4(cop0, v);
 599                 }
 600                 break;
 601         case KVM_REG_MIPS_CP0_CONFIG5:
 602                 cur = kvm_read_c0_guest_config5(cop0);
 603                 change = (cur ^ v) & kvm_mips_config5_wrmask(vcpu);
 604                 if (change) {
 605                         v = cur ^ change;
 606                         kvm_write_c0_guest_config5(cop0, v);
 607                 }
 608                 break;
 609         case KVM_REG_MIPS_COUNT_CTL:
 610                 ret = kvm_mips_set_count_ctl(vcpu, v);
 611                 break;
 612         case KVM_REG_MIPS_COUNT_RESUME:
 613                 ret = kvm_mips_set_count_resume(vcpu, v);
 614                 break;
 615         case KVM_REG_MIPS_COUNT_HZ:
 616                 ret = kvm_mips_set_count_hz(vcpu, v);
 617                 break;
 618         default:
 619                 return -EINVAL;
 620         }
 621         return ret;
 622 }
 623
 624 static int kvm_trap_emul_vcpu_get_regs(struct kvm_vcpu *vcpu)
 625 {
 626         kvm_lose_fpu(vcpu);
 627
 628         return 0;
 629 }
 630
 631 static int kvm_trap_emul_vcpu_set_regs(struct kvm_vcpu *vcpu)
 632 {
 633         return 0;
 634 }
 635
 636 static struct kvm_mips_callbacks kvm_trap_emul_callbacks = {
 637         /* exit handlers */
 638         .handle_cop_unusable = kvm_trap_emul_handle_cop_unusable,
 639         .handle_tlb_mod = kvm_trap_emul_handle_tlb_mod,
 640         .handle_tlb_st_miss = kvm_trap_emul_handle_tlb_st_miss,
 641         .handle_tlb_ld_miss = kvm_trap_emul_handle_tlb_ld_miss,
 642         .handle_addr_err_st = kvm_trap_emul_handle_addr_err_st,
 643         .handle_addr_err_ld = kvm_trap_emul_handle_addr_err_ld,
 644         .handle_syscall = kvm_trap_emul_handle_syscall,
 645         .handle_res_inst = kvm_trap_emul_handle_res_inst,
 646         .handle_break = kvm_trap_emul_handle_break,
 647         .handle_trap = kvm_trap_emul_handle_trap,
 648         .handle_msa_fpe = kvm_trap_emul_handle_msa_fpe,
 649         .handle_fpe = kvm_trap_emul_handle_fpe,
 650         .handle_msa_disabled = kvm_trap_emul_handle_msa_disabled,
 651
 652         .vm_init = kvm_trap_emul_vm_init,
 653         .vcpu_init = kvm_trap_emul_vcpu_init,
 654         .vcpu_setup = kvm_trap_emul_vcpu_setup,
 655         .gva_to_gpa = kvm_trap_emul_gva_to_gpa_cb,
 656         .queue_timer_int = kvm_mips_queue_timer_int_cb,
 657         .dequeue_timer_int = kvm_mips_dequeue_timer_int_cb,
 658         .queue_io_int = kvm_mips_queue_io_int_cb,
 659         .dequeue_io_int = kvm_mips_dequeue_io_int_cb,
 660         .irq_deliver = kvm_mips_irq_deliver_cb,
 661         .irq_clear = kvm_mips_irq_clear_cb,
 662         .get_one_reg = kvm_trap_emul_get_one_reg,
 663         .set_one_reg = kvm_trap_emul_set_one_reg,
 664         .vcpu_get_regs = kvm_trap_emul_vcpu_get_regs,
 665         .vcpu_set_regs = kvm_trap_emul_vcpu_set_regs,
 666 };
 667
 668 int kvm_mips_emulation_init(struct kvm_mips_callbacks **install_callbacks)
 669 {
 670         *install_callbacks = &kvm_trap_emul_callbacks;
 671         return 0;
 672 }