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 "opcode.h"
  20 #include "interrupt.h"
  21
  22 static gpa_t kvm_trap_emul_gva_to_gpa_cb(gva_t gva)
  23 {
  24         gpa_t gpa;
  25         uint32_t kseg = KSEGX(gva);
  26
  27         if ((kseg == CKSEG0) || (kseg == CKSEG1))
  28                 gpa = CPHYSADDR(gva);
  29         else {
  30                 kvm_err("%s: cannot find GPA for GVA: %#lx\n", __func__, gva);
  31                 kvm_mips_dump_host_tlbs();
  32                 gpa = KVM_INVALID_ADDR;
  33         }
  34
  35         kvm_debug("%s: gva %#lx, gpa: %#llx\n", __func__, gva, gpa);
  36
  37         return gpa;
  38 }
  39
  40 static int kvm_trap_emul_handle_cop_unusable(struct kvm_vcpu *vcpu)
  41 {
  42         struct mips_coproc *cop0 = vcpu->arch.cop0;
  43         struct kvm_run *run = vcpu->run;
  44         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
  45         unsigned long cause = vcpu->arch.host_cp0_cause;
  46         enum emulation_result er = EMULATE_DONE;
  47         int ret = RESUME_GUEST;
  48
  49         if (((cause & CAUSEF_CE) >> CAUSEB_CE) == 1) {
  50                 /* FPU Unusable */
  51                 if (!kvm_mips_guest_has_fpu(&vcpu->arch) ||
  52                     (kvm_read_c0_guest_status(cop0) & ST0_CU1) == 0) {
  53                         /*
  54                          * Unusable/no FPU in guest:
  55                          * deliver guest COP1 Unusable Exception
  56                          */
  57                         er = kvm_mips_emulate_fpu_exc(cause, opc, run, vcpu);
  58                 } else {
  59                         /* Restore FPU state */
  60                         kvm_own_fpu(vcpu);
  61                         er = EMULATE_DONE;
  62                 }
  63         } else {
  64                 er = kvm_mips_emulate_inst(cause, opc, run, vcpu);
  65         }
  66
  67         switch (er) {
  68         case EMULATE_DONE:
  69                 ret = RESUME_GUEST;
  70                 break;
  71
  72         case EMULATE_FAIL:
  73                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
  74                 ret = RESUME_HOST;
  75                 break;
  76
  77         case EMULATE_WAIT:
  78                 run->exit_reason = KVM_EXIT_INTR;
  79                 ret = RESUME_HOST;
  80                 break;
  81
  82         default:
  83                 BUG();
  84         }
  85         return ret;
  86 }
  87
  88 static int kvm_trap_emul_handle_tlb_mod(struct kvm_vcpu *vcpu)
  89 {
  90         struct kvm_run *run = vcpu->run;
  91         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
  92         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
  93         unsigned long cause = vcpu->arch.host_cp0_cause;
  94         enum emulation_result er = EMULATE_DONE;
  95         int ret = RESUME_GUEST;
  96
  97         if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
  98             || KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
  99                 kvm_debug("USER/KSEG23 ADDR TLB MOD fault: cause %#lx, PC: %p, BadVaddr: %#lx\n",
 100                           cause, opc, badvaddr);
 101                 er = kvm_mips_handle_tlbmod(cause, opc, run, vcpu);
 102
 103                 if (er == EMULATE_DONE)
 104                         ret = RESUME_GUEST;
 105                 else {
 106                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 107                         ret = RESUME_HOST;
 108                 }
 109         } else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
 110                 /*
 111                  * XXXKYMA: The guest kernel does not expect to get this fault
 112                  * when we are not using HIGHMEM. Need to address this in a
 113                  * HIGHMEM kernel
 114                  */
 115                 kvm_err("TLB MOD fault not handled, cause %#lx, PC: %p, BadVaddr: %#lx\n",
 116                         cause, opc, badvaddr);
 117                 kvm_mips_dump_host_tlbs();
 118                 kvm_arch_vcpu_dump_regs(vcpu);
 119                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 120                 ret = RESUME_HOST;
 121         } else {
 122                 kvm_err("Illegal TLB Mod fault address , cause %#lx, PC: %p, BadVaddr: %#lx\n",
 123                         cause, opc, badvaddr);
 124                 kvm_mips_dump_host_tlbs();
 125                 kvm_arch_vcpu_dump_regs(vcpu);
 126                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 127                 ret = RESUME_HOST;
 128         }
 129         return ret;
 130 }
 131
 132 static int kvm_trap_emul_handle_tlb_st_miss(struct kvm_vcpu *vcpu)
 133 {
 134         struct kvm_run *run = vcpu->run;
 135         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 136         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
 137         unsigned long cause = vcpu->arch.host_cp0_cause;
 138         enum emulation_result er = EMULATE_DONE;
 139         int ret = RESUME_GUEST;
 140
 141         if (((badvaddr & PAGE_MASK) == KVM_GUEST_COMMPAGE_ADDR)
 142             && KVM_GUEST_KERNEL_MODE(vcpu)) {
 143                 if (kvm_mips_handle_commpage_tlb_fault(badvaddr, vcpu) < 0) {
 144                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 145                         ret = RESUME_HOST;
 146                 }
 147         } else if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
 148                    || KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
 149                 kvm_debug("USER ADDR TLB LD fault: cause %#lx, PC: %p, BadVaddr: %#lx\n",
 150                           cause, opc, badvaddr);
 151                 er = kvm_mips_handle_tlbmiss(cause, opc, run, vcpu);
 152                 if (er == EMULATE_DONE)
 153                         ret = RESUME_GUEST;
 154                 else {
 155                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 156                         ret = RESUME_HOST;
 157                 }
 158         } else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
 159                 /*
 160                  * All KSEG0 faults are handled by KVM, as the guest kernel does
 161                  * not expect to ever get them
 162                  */
 163                 if (kvm_mips_handle_kseg0_tlb_fault
 164                     (vcpu->arch.host_cp0_badvaddr, vcpu) < 0) {
 165                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 166                         ret = RESUME_HOST;
 167                 }
 168         } else {
 169                 kvm_err("Illegal TLB LD fault address , cause %#lx, PC: %p, BadVaddr: %#lx\n",
 170                         cause, opc, badvaddr);
 171                 kvm_mips_dump_host_tlbs();
 172                 kvm_arch_vcpu_dump_regs(vcpu);
 173                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 174                 ret = RESUME_HOST;
 175         }
 176         return ret;
 177 }
 178
 179 static int kvm_trap_emul_handle_tlb_ld_miss(struct kvm_vcpu *vcpu)
 180 {
 181         struct kvm_run *run = vcpu->run;
 182         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 183         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
 184         unsigned long cause = vcpu->arch.host_cp0_cause;
 185         enum emulation_result er = EMULATE_DONE;
 186         int ret = RESUME_GUEST;
 187
 188         if (((badvaddr & PAGE_MASK) == KVM_GUEST_COMMPAGE_ADDR)
 189             && KVM_GUEST_KERNEL_MODE(vcpu)) {
 190                 if (kvm_mips_handle_commpage_tlb_fault(badvaddr, vcpu) < 0) {
 191                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 192                         ret = RESUME_HOST;
 193                 }
 194         } else if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
 195                    || KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
 196                 kvm_debug("USER ADDR TLB ST fault: PC: %#lx, BadVaddr: %#lx\n",
 197                           vcpu->arch.pc, badvaddr);
 198
 199                 /*
 200                  * User Address (UA) fault, this could happen if
 201                  * (1) TLB entry not present/valid in both Guest and shadow host
 202                  *     TLBs, in this case we pass on the fault to the guest
 203                  *     kernel and let it handle it.
 204                  * (2) TLB entry is present in the Guest TLB but not in the
 205                  *     shadow, in this case we inject the TLB from the Guest TLB
 206                  *     into the shadow host TLB
 207                  */
 208
 209                 er = kvm_mips_handle_tlbmiss(cause, opc, run, vcpu);
 210                 if (er == EMULATE_DONE)
 211                         ret = RESUME_GUEST;
 212                 else {
 213                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 214                         ret = RESUME_HOST;
 215                 }
 216         } else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
 217                 if (kvm_mips_handle_kseg0_tlb_fault
 218                     (vcpu->arch.host_cp0_badvaddr, vcpu) < 0) {
 219                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 220                         ret = RESUME_HOST;
 221                 }
 222         } else {
 223                 kvm_err("Illegal TLB ST fault address , cause %#lx, PC: %p, BadVaddr: %#lx\n",
 224                         cause, opc, badvaddr);
 225                 kvm_mips_dump_host_tlbs();
 226                 kvm_arch_vcpu_dump_regs(vcpu);
 227                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 228                 ret = RESUME_HOST;
 229         }
 230         return ret;
 231 }
 232
 233 static int kvm_trap_emul_handle_addr_err_st(struct kvm_vcpu *vcpu)
 234 {
 235         struct kvm_run *run = vcpu->run;
 236         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 237         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
 238         unsigned long cause = vcpu->arch.host_cp0_cause;
 239         enum emulation_result er = EMULATE_DONE;
 240         int ret = RESUME_GUEST;
 241
 242         if (KVM_GUEST_KERNEL_MODE(vcpu)
 243             && (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1)) {
 244                 kvm_debug("Emulate Store to MMIO space\n");
 245                 er = kvm_mips_emulate_inst(cause, opc, run, vcpu);
 246                 if (er == EMULATE_FAIL) {
 247                         kvm_err("Emulate Store to MMIO space failed\n");
 248                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 249                         ret = RESUME_HOST;
 250                 } else {
 251                         run->exit_reason = KVM_EXIT_MMIO;
 252                         ret = RESUME_HOST;
 253                 }
 254         } else {
 255                 kvm_err("Address Error (STORE): cause %#lx, PC: %p, BadVaddr: %#lx\n",
 256                         cause, opc, badvaddr);
 257                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 258                 ret = RESUME_HOST;
 259         }
 260         return ret;
 261 }
 262
 263 static int kvm_trap_emul_handle_addr_err_ld(struct kvm_vcpu *vcpu)
 264 {
 265         struct kvm_run *run = vcpu->run;
 266         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 267         unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
 268         unsigned long cause = vcpu->arch.host_cp0_cause;
 269         enum emulation_result er = EMULATE_DONE;
 270         int ret = RESUME_GUEST;
 271
 272         if (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1) {
 273                 kvm_debug("Emulate Load from MMIO space @ %#lx\n", badvaddr);
 274                 er = kvm_mips_emulate_inst(cause, opc, run, vcpu);
 275                 if (er == EMULATE_FAIL) {
 276                         kvm_err("Emulate Load from MMIO space failed\n");
 277                         run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 278                         ret = RESUME_HOST;
 279                 } else {
 280                         run->exit_reason = KVM_EXIT_MMIO;
 281                         ret = RESUME_HOST;
 282                 }
 283         } else {
 284                 kvm_err("Address Error (LOAD): cause %#lx, PC: %p, BadVaddr: %#lx\n",
 285                         cause, opc, badvaddr);
 286                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 287                 ret = RESUME_HOST;
 288                 er = EMULATE_FAIL;
 289         }
 290         return ret;
 291 }
 292
 293 static int kvm_trap_emul_handle_syscall(struct kvm_vcpu *vcpu)
 294 {
 295         struct kvm_run *run = vcpu->run;
 296         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 297         unsigned long cause = vcpu->arch.host_cp0_cause;
 298         enum emulation_result er = EMULATE_DONE;
 299         int ret = RESUME_GUEST;
 300
 301         er = kvm_mips_emulate_syscall(cause, opc, run, vcpu);
 302         if (er == EMULATE_DONE)
 303                 ret = RESUME_GUEST;
 304         else {
 305                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 306                 ret = RESUME_HOST;
 307         }
 308         return ret;
 309 }
 310
 311 static int kvm_trap_emul_handle_res_inst(struct kvm_vcpu *vcpu)
 312 {
 313         struct kvm_run *run = vcpu->run;
 314         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 315         unsigned long cause = vcpu->arch.host_cp0_cause;
 316         enum emulation_result er = EMULATE_DONE;
 317         int ret = RESUME_GUEST;
 318
 319         er = kvm_mips_handle_ri(cause, opc, run, vcpu);
 320         if (er == EMULATE_DONE)
 321                 ret = RESUME_GUEST;
 322         else {
 323                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 324                 ret = RESUME_HOST;
 325         }
 326         return ret;
 327 }
 328
 329 static int kvm_trap_emul_handle_break(struct kvm_vcpu *vcpu)
 330 {
 331         struct kvm_run *run = vcpu->run;
 332         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 333         unsigned long cause = vcpu->arch.host_cp0_cause;
 334         enum emulation_result er = EMULATE_DONE;
 335         int ret = RESUME_GUEST;
 336
 337         er = kvm_mips_emulate_bp_exc(cause, opc, run, vcpu);
 338         if (er == EMULATE_DONE)
 339                 ret = RESUME_GUEST;
 340         else {
 341                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 342                 ret = RESUME_HOST;
 343         }
 344         return ret;
 345 }
 346
 347 static int kvm_trap_emul_handle_trap(struct kvm_vcpu *vcpu)
 348 {
 349         struct kvm_run *run = vcpu->run;
 350         uint32_t __user *opc = (uint32_t __user *)vcpu->arch.pc;
 351         unsigned long cause = vcpu->arch.host_cp0_cause;
 352         enum emulation_result er = EMULATE_DONE;
 353         int ret = RESUME_GUEST;
 354
 355         er = kvm_mips_emulate_trap_exc(cause, opc, run, vcpu);
 356         if (er == EMULATE_DONE) {
 357                 ret = RESUME_GUEST;
 358         } else {
 359                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 360                 ret = RESUME_HOST;
 361         }
 362         return ret;
 363 }
 364
 365 static int kvm_trap_emul_handle_msa_fpe(struct kvm_vcpu *vcpu)
 366 {
 367         struct kvm_run *run = vcpu->run;
 368         uint32_t __user *opc = (uint32_t __user *)vcpu->arch.pc;
 369         unsigned long cause = vcpu->arch.host_cp0_cause;
 370         enum emulation_result er = EMULATE_DONE;
 371         int ret = RESUME_GUEST;
 372
 373         er = kvm_mips_emulate_msafpe_exc(cause, opc, run, vcpu);
 374         if (er == EMULATE_DONE) {
 375                 ret = RESUME_GUEST;
 376         } else {
 377                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 378                 ret = RESUME_HOST;
 379         }
 380         return ret;
 381 }
 382
 383 static int kvm_trap_emul_handle_fpe(struct kvm_vcpu *vcpu)
 384 {
 385         struct kvm_run *run = vcpu->run;
 386         uint32_t __user *opc = (uint32_t __user *)vcpu->arch.pc;
 387         unsigned long cause = vcpu->arch.host_cp0_cause;
 388         enum emulation_result er = EMULATE_DONE;
 389         int ret = RESUME_GUEST;
 390
 391         er = kvm_mips_emulate_fpe_exc(cause, opc, run, vcpu);
 392         if (er == EMULATE_DONE) {
 393                 ret = RESUME_GUEST;
 394         } else {
 395                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 396                 ret = RESUME_HOST;
 397         }
 398         return ret;
 399 }
 400
 401 /**
 402  * kvm_trap_emul_handle_msa_disabled() - Guest used MSA while disabled in root.
 403  * @vcpu:       Virtual CPU context.
 404  *
 405  * Handle when the guest attempts to use MSA when it is disabled.
 406  */
 407 static int kvm_trap_emul_handle_msa_disabled(struct kvm_vcpu *vcpu)
 408 {
 409         struct mips_coproc *cop0 = vcpu->arch.cop0;
 410         struct kvm_run *run = vcpu->run;
 411         uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
 412         unsigned long cause = vcpu->arch.host_cp0_cause;
 413         enum emulation_result er = EMULATE_DONE;
 414         int ret = RESUME_GUEST;
 415
 416         if (!kvm_mips_guest_has_msa(&vcpu->arch) ||
 417             (kvm_read_c0_guest_status(cop0) & (ST0_CU1 | ST0_FR)) == ST0_CU1) {
 418                 /*
 419                  * No MSA in guest, or FPU enabled and not in FR=1 mode,
 420                  * guest reserved instruction exception
 421                  */
 422                 er = kvm_mips_emulate_ri_exc(cause, opc, run, vcpu);
 423         } else if (!(kvm_read_c0_guest_config5(cop0) & MIPS_CONF5_MSAEN)) {
 424                 /* MSA disabled by guest, guest MSA disabled exception */
 425                 er = kvm_mips_emulate_msadis_exc(cause, opc, run, vcpu);
 426         } else {
 427                 /* Restore MSA/FPU state */
 428                 kvm_own_msa(vcpu);
 429                 er = EMULATE_DONE;
 430         }
 431
 432         switch (er) {
 433         case EMULATE_DONE:
 434                 ret = RESUME_GUEST;
 435                 break;
 436
 437         case EMULATE_FAIL:
 438                 run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
 439                 ret = RESUME_HOST;
 440                 break;
 441
 442         default:
 443                 BUG();
 444         }
 445         return ret;
 446 }
 447
 448 static int kvm_trap_emul_vm_init(struct kvm *kvm)
 449 {
 450         return 0;
 451 }
 452
 453 static int kvm_trap_emul_vcpu_init(struct kvm_vcpu *vcpu)
 454 {
 455         return 0;
 456 }
 457
 458 static int kvm_trap_emul_vcpu_setup(struct kvm_vcpu *vcpu)
 459 {
 460         struct mips_coproc *cop0 = vcpu->arch.cop0;
 461         uint32_t config1;
 462         int vcpu_id = vcpu->vcpu_id;
 463
 464         /*
 465          * Arch specific stuff, set up config registers properly so that the
 466          * guest will come up as expected, for now we simulate a MIPS 24kc
 467          */
 468         kvm_write_c0_guest_prid(cop0, 0x00019300);
 469         /* Have config1, Cacheable, noncoherent, write-back, write allocate */
 470         kvm_write_c0_guest_config(cop0, MIPS_CONF_M | (0x3 << CP0C0_K0) |
 471                                   (0x1 << CP0C0_AR) |
 472                                   (MMU_TYPE_R4000 << CP0C0_MT));
 473
 474         /* Read the cache characteristics from the host Config1 Register */
 475         config1 = (read_c0_config1() & ~0x7f);
 476
 477         /* Set up MMU size */
 478         config1 &= ~(0x3f << 25);
 479         config1 |= ((KVM_MIPS_GUEST_TLB_SIZE - 1) << 25);
 480
 481         /* We unset some bits that we aren't emulating */
 482         config1 &=
 483             ~((1 << CP0C1_C2) | (1 << CP0C1_MD) | (1 << CP0C1_PC) |
 484               (1 << CP0C1_WR) | (1 << CP0C1_CA));
 485         kvm_write_c0_guest_config1(cop0, config1);
 486
 487         /* Have config3, no tertiary/secondary caches implemented */
 488         kvm_write_c0_guest_config2(cop0, MIPS_CONF_M);
 489         /* MIPS_CONF_M | (read_c0_config2() & 0xfff) */
 490
 491         /* Have config4, UserLocal */
 492         kvm_write_c0_guest_config3(cop0, MIPS_CONF_M | MIPS_CONF3_ULRI);
 493
 494         /* Have config5 */
 495         kvm_write_c0_guest_config4(cop0, MIPS_CONF_M);
 496
 497         /* No config6 */
 498         kvm_write_c0_guest_config5(cop0, 0);
 499
 500         /* Set Wait IE/IXMT Ignore in Config7, IAR, AR */
 501         kvm_write_c0_guest_config7(cop0, (MIPS_CONF7_WII) | (1 << 10));
 502
 503         /*
 504          * Setup IntCtl defaults, compatibilty mode for timer interrupts (HW5)
 505          */
 506         kvm_write_c0_guest_intctl(cop0, 0xFC000000);
 507
 508         /* Put in vcpu id as CPUNum into Ebase Reg to handle SMP Guests */
 509         kvm_write_c0_guest_ebase(cop0, KVM_GUEST_KSEG0 | (vcpu_id & 0xFF));
 510
 511         return 0;
 512 }
 513
 514 static int kvm_trap_emul_get_one_reg(struct kvm_vcpu *vcpu,
 515                                      const struct kvm_one_reg *reg,
 516                                      s64 *v)
 517 {
 518         switch (reg->id) {
 519         case KVM_REG_MIPS_CP0_COUNT:
 520                 *v = kvm_mips_read_count(vcpu);
 521                 break;
 522         case KVM_REG_MIPS_COUNT_CTL:
 523                 *v = vcpu->arch.count_ctl;
 524                 break;
 525         case KVM_REG_MIPS_COUNT_RESUME:
 526                 *v = ktime_to_ns(vcpu->arch.count_resume);
 527                 break;
 528         case KVM_REG_MIPS_COUNT_HZ:
 529                 *v = vcpu->arch.count_hz;
 530                 break;
 531         default:
 532                 return -EINVAL;
 533         }
 534         return 0;
 535 }
 536
 537 static int kvm_trap_emul_set_one_reg(struct kvm_vcpu *vcpu,
 538                                      const struct kvm_one_reg *reg,
 539                                      s64 v)
 540 {
 541         struct mips_coproc *cop0 = vcpu->arch.cop0;
 542         int ret = 0;
 543         unsigned int cur, change;
 544
 545         switch (reg->id) {
 546         case KVM_REG_MIPS_CP0_COUNT:
 547                 kvm_mips_write_count(vcpu, v);
 548                 break;
 549         case KVM_REG_MIPS_CP0_COMPARE:
 550                 kvm_mips_write_compare(vcpu, v);
 551                 break;
 552         case KVM_REG_MIPS_CP0_CAUSE:
 553                 /*
 554                  * If the timer is stopped or started (DC bit) it must look
 555                  * atomic with changes to the interrupt pending bits (TI, IRQ5).
 556                  * A timer interrupt should not happen in between.
 557                  */
 558                 if ((kvm_read_c0_guest_cause(cop0) ^ v) & CAUSEF_DC) {
 559                         if (v & CAUSEF_DC) {
 560                                 /* disable timer first */
 561                                 kvm_mips_count_disable_cause(vcpu);
 562                                 kvm_change_c0_guest_cause(cop0, ~CAUSEF_DC, v);
 563                         } else {
 564                                 /* enable timer last */
 565                                 kvm_change_c0_guest_cause(cop0, ~CAUSEF_DC, v);
 566                                 kvm_mips_count_enable_cause(vcpu);
 567                         }
 568                 } else {
 569                         kvm_write_c0_guest_cause(cop0, v);
 570                 }
 571                 break;
 572         case KVM_REG_MIPS_CP0_CONFIG:
 573                 /* read-only for now */
 574                 break;
 575         case KVM_REG_MIPS_CP0_CONFIG1:
 576                 cur = kvm_read_c0_guest_config1(cop0);
 577                 change = (cur ^ v) & kvm_mips_config1_wrmask(vcpu);
 578                 if (change) {
 579                         v = cur ^ change;
 580                         kvm_write_c0_guest_config1(cop0, v);
 581                 }
 582                 break;
 583         case KVM_REG_MIPS_CP0_CONFIG2:
 584                 /* read-only for now */
 585                 break;
 586         case KVM_REG_MIPS_CP0_CONFIG3:
 587                 cur = kvm_read_c0_guest_config3(cop0);
 588                 change = (cur ^ v) & kvm_mips_config3_wrmask(vcpu);
 589                 if (change) {
 590                         v = cur ^ change;
 591                         kvm_write_c0_guest_config3(cop0, v);
 592                 }
 593                 break;
 594         case KVM_REG_MIPS_CP0_CONFIG4:
 595                 cur = kvm_read_c0_guest_config4(cop0);
 596                 change = (cur ^ v) & kvm_mips_config4_wrmask(vcpu);
 597                 if (change) {
 598                         v = cur ^ change;
 599                         kvm_write_c0_guest_config4(cop0, v);
 600                 }
 601                 break;
 602         case KVM_REG_MIPS_CP0_CONFIG5:
 603                 cur = kvm_read_c0_guest_config5(cop0);
 604                 change = (cur ^ v) & kvm_mips_config5_wrmask(vcpu);
 605                 if (change) {
 606                         v = cur ^ change;
 607                         kvm_write_c0_guest_config5(cop0, v);
 608                 }
 609                 break;
 610         case KVM_REG_MIPS_COUNT_CTL:
 611                 ret = kvm_mips_set_count_ctl(vcpu, v);
 612                 break;
 613         case KVM_REG_MIPS_COUNT_RESUME:
 614                 ret = kvm_mips_set_count_resume(vcpu, v);
 615                 break;
 616         case KVM_REG_MIPS_COUNT_HZ:
 617                 ret = kvm_mips_set_count_hz(vcpu, v);
 618                 break;
 619         default:
 620                 return -EINVAL;
 621         }
 622         return ret;
 623 }
 624
 625 static int kvm_trap_emul_vcpu_get_regs(struct kvm_vcpu *vcpu)
 626 {
 627         kvm_lose_fpu(vcpu);
 628
 629         return 0;
 630 }
 631
 632 static int kvm_trap_emul_vcpu_set_regs(struct kvm_vcpu *vcpu)
 633 {
 634         return 0;
 635 }
 636
 637 static struct kvm_mips_callbacks kvm_trap_emul_callbacks = {
 638         /* exit handlers */
 639         .handle_cop_unusable = kvm_trap_emul_handle_cop_unusable,
 640         .handle_tlb_mod = kvm_trap_emul_handle_tlb_mod,
 641         .handle_tlb_st_miss = kvm_trap_emul_handle_tlb_st_miss,
 642         .handle_tlb_ld_miss = kvm_trap_emul_handle_tlb_ld_miss,
 643         .handle_addr_err_st = kvm_trap_emul_handle_addr_err_st,
 644         .handle_addr_err_ld = kvm_trap_emul_handle_addr_err_ld,
 645         .handle_syscall = kvm_trap_emul_handle_syscall,
 646         .handle_res_inst = kvm_trap_emul_handle_res_inst,
 647         .handle_break = kvm_trap_emul_handle_break,
 648         .handle_trap = kvm_trap_emul_handle_trap,
 649         .handle_msa_fpe = kvm_trap_emul_handle_msa_fpe,
 650         .handle_fpe = kvm_trap_emul_handle_fpe,
 651         .handle_msa_disabled = kvm_trap_emul_handle_msa_disabled,
 652
 653         .vm_init = kvm_trap_emul_vm_init,
 654         .vcpu_init = kvm_trap_emul_vcpu_init,
 655         .vcpu_setup = kvm_trap_emul_vcpu_setup,
 656         .gva_to_gpa = kvm_trap_emul_gva_to_gpa_cb,
 657         .queue_timer_int = kvm_mips_queue_timer_int_cb,
 658         .dequeue_timer_int = kvm_mips_dequeue_timer_int_cb,
 659         .queue_io_int = kvm_mips_queue_io_int_cb,
 660         .dequeue_io_int = kvm_mips_dequeue_io_int_cb,
 661         .irq_deliver = kvm_mips_irq_deliver_cb,
 662         .irq_clear = kvm_mips_irq_clear_cb,
 663         .get_one_reg = kvm_trap_emul_get_one_reg,
 664         .set_one_reg = kvm_trap_emul_set_one_reg,
 665         .vcpu_get_regs = kvm_trap_emul_vcpu_get_regs,
 666         .vcpu_set_regs = kvm_trap_emul_vcpu_set_regs,
 667 };
 668
 669 int kvm_mips_emulation_init(struct kvm_mips_callbacks **install_callbacks)
 670 {
 671         *install_callbacks = &kvm_trap_emul_callbacks;
 672         return 0;
 673 }