arch/powerpc/kvm/book3s_emulate.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License, version 2, as
   4  * published by the Free Software Foundation.
   5  *
   6  * This program is distributed in the hope that it will be useful,
   7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9  * GNU General Public License for more details.
  10  *
  11  * You should have received a copy of the GNU General Public License
  12  * along with this program; if not, write to the Free Software
  13  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  14  *
  15  * Copyright SUSE Linux Products GmbH 2009
  16  *
  17  * Authors: Alexander Graf <agraf@suse.de>
  18  */
  19
  20 #include <asm/kvm_ppc.h>
  21 #include <asm/disassemble.h>
  22 #include <asm/kvm_book3s.h>
  23 #include <asm/reg.h>
  24
  25 #define OP_19_XOP_RFID          18
  26 #define OP_19_XOP_RFI           50
  27
  28 #define OP_31_XOP_MFMSR         83
  29 #define OP_31_XOP_MTMSR         146
  30 #define OP_31_XOP_MTMSRD        178
  31 #define OP_31_XOP_MTSR          210
  32 #define OP_31_XOP_MTSRIN        242
  33 #define OP_31_XOP_TLBIEL        274
  34 #define OP_31_XOP_TLBIE         306
  35 #define OP_31_XOP_SLBMTE        402
  36 #define OP_31_XOP_SLBIE         434
  37 #define OP_31_XOP_SLBIA         498
  38 #define OP_31_XOP_MFSR          595
  39 #define OP_31_XOP_MFSRIN        659
  40 #define OP_31_XOP_DCBA          758
  41 #define OP_31_XOP_SLBMFEV       851
  42 #define OP_31_XOP_EIOIO         854
  43 #define OP_31_XOP_SLBMFEE       915
  44
  45 /* DCBZ is actually 1014, but we patch it to 1010 so we get a trap */
  46 #define OP_31_XOP_DCBZ          1010
  47
  48 #define OP_LFS                  48
  49 #define OP_LFD                  50
  50 #define OP_STFS                 52
  51 #define OP_STFD                 54
  52
  53 #define SPRN_GQR0               912
  54 #define SPRN_GQR1               913
  55 #define SPRN_GQR2               914
  56 #define SPRN_GQR3               915
  57 #define SPRN_GQR4               916
  58 #define SPRN_GQR5               917
  59 #define SPRN_GQR6               918
  60 #define SPRN_GQR7               919
  61
  62 /* Book3S_32 defines mfsrin(v) - but that messes up our abstract
  63  * function pointers, so let's just disable the define. */
  64 #undef mfsrin
  65
  66 enum priv_level {
  67         PRIV_PROBLEM = 0,
  68         PRIV_SUPER = 1,
  69         PRIV_HYPER = 2,
  70 };
  71
  72 static bool spr_allowed(struct kvm_vcpu *vcpu, enum priv_level level)
  73 {
  74         /* PAPR VMs only access supervisor SPRs */
  75         if (vcpu->arch.papr_enabled && (level > PRIV_SUPER))
  76                 return false;
  77
  78         /* Limit user space to its own small SPR set */
  79         if ((vcpu->arch.shared->msr & MSR_PR) && level > PRIV_PROBLEM)
  80                 return false;
  81
  82         return true;
  83 }
  84
  85 int kvmppc_core_emulate_op(struct kvm_run *run, struct kvm_vcpu *vcpu,
  86                            unsigned int inst, int *advance)
  87 {
  88         int emulated = EMULATE_DONE;
  89
  90         switch (get_op(inst)) {
  91         case 19:
  92                 switch (get_xop(inst)) {
  93                 case OP_19_XOP_RFID:
  94                 case OP_19_XOP_RFI:
  95                         kvmppc_set_pc(vcpu, vcpu->arch.shared->srr0);
  96                         kvmppc_set_msr(vcpu, vcpu->arch.shared->srr1);
  97                         *advance = 0;
  98                         break;
  99
 100                 default:
 101                         emulated = EMULATE_FAIL;
 102                         break;
 103                 }
 104                 break;
 105         case 31:
 106                 switch (get_xop(inst)) {
 107                 case OP_31_XOP_MFMSR:
 108                         kvmppc_set_gpr(vcpu, get_rt(inst),
 109                                        vcpu->arch.shared->msr);
 110                         break;
 111                 case OP_31_XOP_MTMSRD:
 112                 {
 113                         ulong rs = kvmppc_get_gpr(vcpu, get_rs(inst));
 114                         if (inst & 0x10000) {
 115                                 vcpu->arch.shared->msr &= ~(MSR_RI | MSR_EE);
 116                                 vcpu->arch.shared->msr |= rs & (MSR_RI | MSR_EE);
 117                         } else
 118                                 kvmppc_set_msr(vcpu, rs);
 119                         break;
 120                 }
 121                 case OP_31_XOP_MTMSR:
 122                         kvmppc_set_msr(vcpu, kvmppc_get_gpr(vcpu, get_rs(inst)));
 123                         break;
 124                 case OP_31_XOP_MFSR:
 125                 {
 126                         int srnum;
 127
 128                         srnum = kvmppc_get_field(inst, 12 + 32, 15 + 32);
 129                         if (vcpu->arch.mmu.mfsrin) {
 130                                 u32 sr;
 131                                 sr = vcpu->arch.mmu.mfsrin(vcpu, srnum);
 132                                 kvmppc_set_gpr(vcpu, get_rt(inst), sr);
 133                         }
 134                         break;
 135                 }
 136                 case OP_31_XOP_MFSRIN:
 137                 {
 138                         int srnum;
 139
 140                         srnum = (kvmppc_get_gpr(vcpu, get_rb(inst)) >> 28) & 0xf;
 141                         if (vcpu->arch.mmu.mfsrin) {
 142                                 u32 sr;
 143                                 sr = vcpu->arch.mmu.mfsrin(vcpu, srnum);
 144                                 kvmppc_set_gpr(vcpu, get_rt(inst), sr);
 145                         }
 146                         break;
 147                 }
 148                 case OP_31_XOP_MTSR:
 149                         vcpu->arch.mmu.mtsrin(vcpu,
 150                                 (inst >> 16) & 0xf,
 151                                 kvmppc_get_gpr(vcpu, get_rs(inst)));
 152                         break;
 153                 case OP_31_XOP_MTSRIN:
 154                         vcpu->arch.mmu.mtsrin(vcpu,
 155                                 (kvmppc_get_gpr(vcpu, get_rb(inst)) >> 28) & 0xf,
 156                                 kvmppc_get_gpr(vcpu, get_rs(inst)));
 157                         break;
 158                 case OP_31_XOP_TLBIE:
 159                 case OP_31_XOP_TLBIEL:
 160                 {
 161                         bool large = (inst & 0x00200000) ? true : false;
 162                         ulong addr = kvmppc_get_gpr(vcpu, get_rb(inst));
 163                         vcpu->arch.mmu.tlbie(vcpu, addr, large);
 164                         break;
 165                 }
 166                 case OP_31_XOP_EIOIO:
 167                         break;
 168                 case OP_31_XOP_SLBMTE:
 169                         if (!vcpu->arch.mmu.slbmte)
 170                                 return EMULATE_FAIL;
 171
 172                         vcpu->arch.mmu.slbmte(vcpu,
 173                                         kvmppc_get_gpr(vcpu, get_rs(inst)),
 174                                         kvmppc_get_gpr(vcpu, get_rb(inst)));
 175                         break;
 176                 case OP_31_XOP_SLBIE:
 177                         if (!vcpu->arch.mmu.slbie)
 178                                 return EMULATE_FAIL;
 179
 180                         vcpu->arch.mmu.slbie(vcpu,
 181                                         kvmppc_get_gpr(vcpu, get_rb(inst)));
 182                         break;
 183                 case OP_31_XOP_SLBIA:
 184                         if (!vcpu->arch.mmu.slbia)
 185                                 return EMULATE_FAIL;
 186
 187                         vcpu->arch.mmu.slbia(vcpu);
 188                         break;
 189                 case OP_31_XOP_SLBMFEE:
 190                         if (!vcpu->arch.mmu.slbmfee) {
 191                                 emulated = EMULATE_FAIL;
 192                         } else {
 193                                 ulong t, rb;
 194
 195                                 rb = kvmppc_get_gpr(vcpu, get_rb(inst));
 196                                 t = vcpu->arch.mmu.slbmfee(vcpu, rb);
 197                                 kvmppc_set_gpr(vcpu, get_rt(inst), t);
 198                         }
 199                         break;
 200                 case OP_31_XOP_SLBMFEV:
 201                         if (!vcpu->arch.mmu.slbmfev) {
 202                                 emulated = EMULATE_FAIL;
 203                         } else {
 204                                 ulong t, rb;
 205
 206                                 rb = kvmppc_get_gpr(vcpu, get_rb(inst));
 207                                 t = vcpu->arch.mmu.slbmfev(vcpu, rb);
 208                                 kvmppc_set_gpr(vcpu, get_rt(inst), t);
 209                         }
 210                         break;
 211                 case OP_31_XOP_DCBA:
 212                         /* Gets treated as NOP */
 213                         break;
 214                 case OP_31_XOP_DCBZ:
 215                 {
 216                         ulong rb = kvmppc_get_gpr(vcpu, get_rb(inst));
 217                         ulong ra = 0;
 218                         ulong addr, vaddr;
 219                         u32 zeros[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
 220                         u32 dsisr;
 221                         int r;
 222
 223                         if (get_ra(inst))
 224                                 ra = kvmppc_get_gpr(vcpu, get_ra(inst));
 225
 226                         addr = (ra + rb) & ~31ULL;
 227                         if (!(vcpu->arch.shared->msr & MSR_SF))
 228                                 addr &= 0xffffffff;
 229                         vaddr = addr;
 230
 231                         r = kvmppc_st(vcpu, &addr, 32, zeros, true);
 232                         if ((r == -ENOENT) || (r == -EPERM)) {
 233                                 *advance = 0;
 234                                 vcpu->arch.shared->dar = vaddr;
 235                                 to_svcpu(vcpu)->fault_dar = vaddr;
 236
 237                                 dsisr = DSISR_ISSTORE;
 238                                 if (r == -ENOENT)
 239                                         dsisr |= DSISR_NOHPTE;
 240                                 else if (r == -EPERM)
 241                                         dsisr |= DSISR_PROTFAULT;
 242
 243                                 vcpu->arch.shared->dsisr = dsisr;
 244                                 to_svcpu(vcpu)->fault_dsisr = dsisr;
 245
 246                                 kvmppc_book3s_queue_irqprio(vcpu,
 247                                         BOOK3S_INTERRUPT_DATA_STORAGE);
 248                         }
 249
 250                         break;
 251                 }
 252                 default:
 253                         emulated = EMULATE_FAIL;
 254                 }
 255                 break;
 256         default:
 257                 emulated = EMULATE_FAIL;
 258         }
 259
 260         if (emulated == EMULATE_FAIL)
 261                 emulated = kvmppc_emulate_paired_single(run, vcpu);
 262
 263         return emulated;
 264 }
 265
 266 void kvmppc_set_bat(struct kvm_vcpu *vcpu, struct kvmppc_bat *bat, bool upper,
 267                     u32 val)
 268 {
 269         if (upper) {
 270                 /* Upper BAT */
 271                 u32 bl = (val >> 2) & 0x7ff;
 272                 bat->bepi_mask = (~bl << 17);
 273                 bat->bepi = val & 0xfffe0000;
 274                 bat->vs = (val & 2) ? 1 : 0;
 275                 bat->vp = (val & 1) ? 1 : 0;
 276                 bat->raw = (bat->raw & 0xffffffff00000000ULL) | val;
 277         } else {
 278                 /* Lower BAT */
 279                 bat->brpn = val & 0xfffe0000;
 280                 bat->wimg = (val >> 3) & 0xf;
 281                 bat->pp = val & 3;
 282                 bat->raw = (bat->raw & 0x00000000ffffffffULL) | ((u64)val << 32);
 283         }
 284 }
 285
 286 static struct kvmppc_bat *kvmppc_find_bat(struct kvm_vcpu *vcpu, int sprn)
 287 {
 288         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 289         struct kvmppc_bat *bat;
 290
 291         switch (sprn) {
 292         case SPRN_IBAT0U ... SPRN_IBAT3L:
 293                 bat = &vcpu_book3s->ibat[(sprn - SPRN_IBAT0U) / 2];
 294                 break;
 295         case SPRN_IBAT4U ... SPRN_IBAT7L:
 296                 bat = &vcpu_book3s->ibat[4 + ((sprn - SPRN_IBAT4U) / 2)];
 297                 break;
 298         case SPRN_DBAT0U ... SPRN_DBAT3L:
 299                 bat = &vcpu_book3s->dbat[(sprn - SPRN_DBAT0U) / 2];
 300                 break;
 301         case SPRN_DBAT4U ... SPRN_DBAT7L:
 302                 bat = &vcpu_book3s->dbat[4 + ((sprn - SPRN_DBAT4U) / 2)];
 303                 break;
 304         default:
 305                 BUG();
 306         }
 307
 308         return bat;
 309 }
 310
 311 int kvmppc_core_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, int rs)
 312 {
 313         int emulated = EMULATE_DONE;
 314         ulong spr_val = kvmppc_get_gpr(vcpu, rs);
 315
 316         switch (sprn) {
 317         case SPRN_SDR1:
 318                 if (!spr_allowed(vcpu, PRIV_HYPER))
 319                         goto unprivileged;
 320                 to_book3s(vcpu)->sdr1 = spr_val;
 321                 break;
 322         case SPRN_DSISR:
 323                 vcpu->arch.shared->dsisr = spr_val;
 324                 break;
 325         case SPRN_DAR:
 326                 vcpu->arch.shared->dar = spr_val;
 327                 break;
 328         case SPRN_HIOR:
 329                 to_book3s(vcpu)->hior = spr_val;
 330                 break;
 331         case SPRN_IBAT0U ... SPRN_IBAT3L:
 332         case SPRN_IBAT4U ... SPRN_IBAT7L:
 333         case SPRN_DBAT0U ... SPRN_DBAT3L:
 334         case SPRN_DBAT4U ... SPRN_DBAT7L:
 335         {
 336                 struct kvmppc_bat *bat = kvmppc_find_bat(vcpu, sprn);
 337
 338                 kvmppc_set_bat(vcpu, bat, !(sprn % 2), (u32)spr_val);
 339                 /* BAT writes happen so rarely that we're ok to flush
 340                  * everything here */
 341                 kvmppc_mmu_pte_flush(vcpu, 0, 0);
 342                 kvmppc_mmu_flush_segments(vcpu);
 343                 break;
 344         }
 345         case SPRN_HID0:
 346                 to_book3s(vcpu)->hid[0] = spr_val;
 347                 break;
 348         case SPRN_HID1:
 349                 to_book3s(vcpu)->hid[1] = spr_val;
 350                 break;
 351         case SPRN_HID2:
 352                 to_book3s(vcpu)->hid[2] = spr_val;
 353                 break;
 354         case SPRN_HID2_GEKKO:
 355                 to_book3s(vcpu)->hid[2] = spr_val;
 356                 /* HID2.PSE controls paired single on gekko */
 357                 switch (vcpu->arch.pvr) {
 358                 case 0x00080200:        /* lonestar 2.0 */
 359                 case 0x00088202:        /* lonestar 2.2 */
 360                 case 0x70000100:        /* gekko 1.0 */
 361                 case 0x00080100:        /* gekko 2.0 */
 362                 case 0x00083203:        /* gekko 2.3a */
 363                 case 0x00083213:        /* gekko 2.3b */
 364                 case 0x00083204:        /* gekko 2.4 */
 365                 case 0x00083214:        /* gekko 2.4e (8SE) - retail HW2 */
 366                 case 0x00087200:        /* broadway */
 367                         if (vcpu->arch.hflags & BOOK3S_HFLAG_NATIVE_PS) {
 368                                 /* Native paired singles */
 369                         } else if (spr_val & (1 << 29)) { /* HID2.PSE */
 370                                 vcpu->arch.hflags |= BOOK3S_HFLAG_PAIRED_SINGLE;
 371                                 kvmppc_giveup_ext(vcpu, MSR_FP);
 372                         } else {
 373                                 vcpu->arch.hflags &= ~BOOK3S_HFLAG_PAIRED_SINGLE;
 374                         }
 375                         break;
 376                 }
 377                 break;
 378         case SPRN_HID4:
 379         case SPRN_HID4_GEKKO:
 380                 to_book3s(vcpu)->hid[4] = spr_val;
 381                 break;
 382         case SPRN_HID5:
 383                 to_book3s(vcpu)->hid[5] = spr_val;
 384                 /* guest HID5 set can change is_dcbz32 */
 385                 if (vcpu->arch.mmu.is_dcbz32(vcpu) &&
 386                     (mfmsr() & MSR_HV))
 387                         vcpu->arch.hflags |= BOOK3S_HFLAG_DCBZ32;
 388                 break;
 389         case SPRN_GQR0:
 390         case SPRN_GQR1:
 391         case SPRN_GQR2:
 392         case SPRN_GQR3:
 393         case SPRN_GQR4:
 394         case SPRN_GQR5:
 395         case SPRN_GQR6:
 396         case SPRN_GQR7:
 397                 to_book3s(vcpu)->gqr[sprn - SPRN_GQR0] = spr_val;
 398                 break;
 399         case SPRN_ICTC:
 400         case SPRN_THRM1:
 401         case SPRN_THRM2:
 402         case SPRN_THRM3:
 403         case SPRN_CTRLF:
 404         case SPRN_CTRLT:
 405         case SPRN_L2CR:
 406         case SPRN_MMCR0_GEKKO:
 407         case SPRN_MMCR1_GEKKO:
 408         case SPRN_PMC1_GEKKO:
 409         case SPRN_PMC2_GEKKO:
 410         case SPRN_PMC3_GEKKO:
 411         case SPRN_PMC4_GEKKO:
 412         case SPRN_WPAR_GEKKO:
 413                 break;
 414 unprivileged:
 415         default:
 416                 printk(KERN_INFO "KVM: invalid SPR write: %d\n", sprn);
 417 #ifndef DEBUG_SPR
 418                 emulated = EMULATE_FAIL;
 419 #endif
 420                 break;
 421         }
 422
 423         return emulated;
 424 }
 425
 426 int kvmppc_core_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, int rt)
 427 {
 428         int emulated = EMULATE_DONE;
 429
 430         switch (sprn) {
 431         case SPRN_IBAT0U ... SPRN_IBAT3L:
 432         case SPRN_IBAT4U ... SPRN_IBAT7L:
 433         case SPRN_DBAT0U ... SPRN_DBAT3L:
 434         case SPRN_DBAT4U ... SPRN_DBAT7L:
 435         {
 436                 struct kvmppc_bat *bat = kvmppc_find_bat(vcpu, sprn);
 437
 438                 if (sprn % 2)
 439                         kvmppc_set_gpr(vcpu, rt, bat->raw >> 32);
 440                 else
 441                         kvmppc_set_gpr(vcpu, rt, bat->raw);
 442
 443                 break;
 444         }
 445         case SPRN_SDR1:
 446                 if (!spr_allowed(vcpu, PRIV_HYPER))
 447                         goto unprivileged;
 448                 kvmppc_set_gpr(vcpu, rt, to_book3s(vcpu)->sdr1);
 449                 break;
 450         case SPRN_DSISR:
 451                 kvmppc_set_gpr(vcpu, rt, vcpu->arch.shared->dsisr);
 452                 break;
 453         case SPRN_DAR:
 454                 kvmppc_set_gpr(vcpu, rt, vcpu->arch.shared->dar);
 455                 break;
 456         case SPRN_HIOR:
 457                 kvmppc_set_gpr(vcpu, rt, to_book3s(vcpu)->hior);
 458                 break;
 459         case SPRN_HID0:
 460                 kvmppc_set_gpr(vcpu, rt, to_book3s(vcpu)->hid[0]);
 461                 break;
 462         case SPRN_HID1:
 463                 kvmppc_set_gpr(vcpu, rt, to_book3s(vcpu)->hid[1]);
 464                 break;
 465         case SPRN_HID2:
 466         case SPRN_HID2_GEKKO:
 467                 kvmppc_set_gpr(vcpu, rt, to_book3s(vcpu)->hid[2]);
 468                 break;
 469         case SPRN_HID4:
 470         case SPRN_HID4_GEKKO:
 471                 kvmppc_set_gpr(vcpu, rt, to_book3s(vcpu)->hid[4]);
 472                 break;
 473         case SPRN_HID5:
 474                 kvmppc_set_gpr(vcpu, rt, to_book3s(vcpu)->hid[5]);
 475                 break;
 476         case SPRN_CFAR:
 477         case SPRN_PURR:
 478                 kvmppc_set_gpr(vcpu, rt, 0);
 479                 break;
 480         case SPRN_GQR0:
 481         case SPRN_GQR1:
 482         case SPRN_GQR2:
 483         case SPRN_GQR3:
 484         case SPRN_GQR4:
 485         case SPRN_GQR5:
 486         case SPRN_GQR6:
 487         case SPRN_GQR7:
 488                 kvmppc_set_gpr(vcpu, rt,
 489                                to_book3s(vcpu)->gqr[sprn - SPRN_GQR0]);
 490                 break;
 491         case SPRN_THRM1:
 492         case SPRN_THRM2:
 493         case SPRN_THRM3:
 494         case SPRN_CTRLF:
 495         case SPRN_CTRLT:
 496         case SPRN_L2CR:
 497         case SPRN_MMCR0_GEKKO:
 498         case SPRN_MMCR1_GEKKO:
 499         case SPRN_PMC1_GEKKO:
 500         case SPRN_PMC2_GEKKO:
 501         case SPRN_PMC3_GEKKO:
 502         case SPRN_PMC4_GEKKO:
 503         case SPRN_WPAR_GEKKO:
 504                 kvmppc_set_gpr(vcpu, rt, 0);
 505                 break;
 506         default:
 507 unprivileged:
 508                 printk(KERN_INFO "KVM: invalid SPR read: %d\n", sprn);
 509 #ifndef DEBUG_SPR
 510                 emulated = EMULATE_FAIL;
 511 #endif
 512                 break;
 513         }
 514
 515         return emulated;
 516 }
 517
 518 u32 kvmppc_alignment_dsisr(struct kvm_vcpu *vcpu, unsigned int inst)
 519 {
 520         u32 dsisr = 0;
 521
 522         /*
 523          * This is what the spec says about DSISR bits (not mentioned = 0):
 524          *
 525          * 12:13                [DS]    Set to bits 30:31
 526          * 15:16                [X]     Set to bits 29:30
 527          * 17                   [X]     Set to bit 25
 528          *                      [D/DS]  Set to bit 5
 529          * 18:21                [X]     Set to bits 21:24
 530          *                      [D/DS]  Set to bits 1:4
 531          * 22:26                        Set to bits 6:10 (RT/RS/FRT/FRS)
 532          * 27:31                        Set to bits 11:15 (RA)
 533          */
 534
 535         switch (get_op(inst)) {
 536         /* D-form */
 537         case OP_LFS:
 538         case OP_LFD:
 539         case OP_STFD:
 540         case OP_STFS:
 541                 dsisr |= (inst >> 12) & 0x4000; /* bit 17 */
 542                 dsisr |= (inst >> 17) & 0x3c00; /* bits 18:21 */
 543                 break;
 544         /* X-form */
 545         case 31:
 546                 dsisr |= (inst << 14) & 0x18000; /* bits 15:16 */
 547                 dsisr |= (inst << 8)  & 0x04000; /* bit 17 */
 548                 dsisr |= (inst << 3)  & 0x03c00; /* bits 18:21 */
 549                 break;
 550         default:
 551                 printk(KERN_INFO "KVM: Unaligned instruction 0x%x\n", inst);
 552                 break;
 553         }
 554
 555         dsisr |= (inst >> 16) & 0x03ff; /* bits 22:31 */
 556
 557         return dsisr;
 558 }
 559
 560 ulong kvmppc_alignment_dar(struct kvm_vcpu *vcpu, unsigned int inst)
 561 {
 562         ulong dar = 0;
 563         ulong ra;
 564
 565         switch (get_op(inst)) {
 566         case OP_LFS:
 567         case OP_LFD:
 568         case OP_STFD:
 569         case OP_STFS:
 570                 ra = get_ra(inst);
 571                 if (ra)
 572                         dar = kvmppc_get_gpr(vcpu, ra);
 573                 dar += (s32)((s16)inst);
 574                 break;
 575         case 31:
 576                 ra = get_ra(inst);
 577                 if (ra)
 578                         dar = kvmppc_get_gpr(vcpu, ra);
 579                 dar += kvmppc_get_gpr(vcpu, get_rb(inst));
 580                 break;
 581         default:
 582                 printk(KERN_INFO "KVM: Unaligned instruction 0x%x\n", inst);
 583                 break;
 584         }
 585
 586         return dar;
 587 }