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 #include <asm/switch_to.h>
  25 #include <asm/time.h>
  26
  27 #define OP_19_XOP_RFID          18
  28 #define OP_19_XOP_RFI           50
  29
  30 #define OP_31_XOP_MFMSR         83
  31 #define OP_31_XOP_MTMSR         146
  32 #define OP_31_XOP_MTMSRD        178
  33 #define OP_31_XOP_MTSR          210
  34 #define OP_31_XOP_MTSRIN        242
  35 #define OP_31_XOP_TLBIEL        274
  36 #define OP_31_XOP_TLBIE         306
  37 #define OP_31_XOP_SLBMTE        402
  38 #define OP_31_XOP_SLBIE         434
  39 #define OP_31_XOP_SLBIA         498
  40 #define OP_31_XOP_MFSR          595
  41 #define OP_31_XOP_MFSRIN        659
  42 #define OP_31_XOP_DCBA          758
  43 #define OP_31_XOP_SLBMFEV       851
  44 #define OP_31_XOP_EIOIO         854
  45 #define OP_31_XOP_SLBMFEE       915
  46
  47 /* DCBZ is actually 1014, but we patch it to 1010 so we get a trap */
  48 #define OP_31_XOP_DCBZ          1010
  49
  50 #define OP_LFS                  48
  51 #define OP_LFD                  50
  52 #define OP_STFS                 52
  53 #define OP_STFD                 54
  54
  55 #define SPRN_GQR0               912
  56 #define SPRN_GQR1               913
  57 #define SPRN_GQR2               914
  58 #define SPRN_GQR3               915
  59 #define SPRN_GQR4               916
  60 #define SPRN_GQR5               917
  61 #define SPRN_GQR6               918
  62 #define SPRN_GQR7               919
  63
  64 /* Book3S_32 defines mfsrin(v) - but that messes up our abstract
  65  * function pointers, so let's just disable the define. */
  66 #undef mfsrin
  67
  68 enum priv_level {
  69         PRIV_PROBLEM = 0,
  70         PRIV_SUPER = 1,
  71         PRIV_HYPER = 2,
  72 };
  73
  74 static bool spr_allowed(struct kvm_vcpu *vcpu, enum priv_level level)
  75 {
  76         /* PAPR VMs only access supervisor SPRs */
  77         if (vcpu->arch.papr_enabled && (level > PRIV_SUPER))
  78                 return false;
  79
  80         /* Limit user space to its own small SPR set */
  81         if ((vcpu->arch.shared->msr & MSR_PR) && level > PRIV_PROBLEM)
  82                 return false;
  83
  84         return true;
  85 }
  86
  87 int kvmppc_core_emulate_op(struct kvm_run *run, struct kvm_vcpu *vcpu,
  88                            unsigned int inst, int *advance)
  89 {
  90         int emulated = EMULATE_DONE;
  91         int rt = get_rt(inst);
  92         int rs = get_rs(inst);
  93         int ra = get_ra(inst);
  94         int rb = get_rb(inst);
  95
  96         switch (get_op(inst)) {
  97         case 19:
  98                 switch (get_xop(inst)) {
  99                 case OP_19_XOP_RFID:
 100                 case OP_19_XOP_RFI:
 101                         kvmppc_set_pc(vcpu, vcpu->arch.shared->srr0);
 102                         kvmppc_set_msr(vcpu, vcpu->arch.shared->srr1);
 103                         *advance = 0;
 104                         break;
 105
 106                 default:
 107                         emulated = EMULATE_FAIL;
 108                         break;
 109                 }
 110                 break;
 111         case 31:
 112                 switch (get_xop(inst)) {
 113                 case OP_31_XOP_MFMSR:
 114                         kvmppc_set_gpr(vcpu, rt, vcpu->arch.shared->msr);
 115                         break;
 116                 case OP_31_XOP_MTMSRD:
 117                 {
 118                         ulong rs_val = kvmppc_get_gpr(vcpu, rs);
 119                         if (inst & 0x10000) {
 120                                 ulong new_msr = vcpu->arch.shared->msr;
 121                                 new_msr &= ~(MSR_RI | MSR_EE);
 122                                 new_msr |= rs_val & (MSR_RI | MSR_EE);
 123                                 vcpu->arch.shared->msr = new_msr;
 124                         } else
 125                                 kvmppc_set_msr(vcpu, rs_val);
 126                         break;
 127                 }
 128                 case OP_31_XOP_MTMSR:
 129                         kvmppc_set_msr(vcpu, kvmppc_get_gpr(vcpu, rs));
 130                         break;
 131                 case OP_31_XOP_MFSR:
 132                 {
 133                         int srnum;
 134
 135                         srnum = kvmppc_get_field(inst, 12 + 32, 15 + 32);
 136                         if (vcpu->arch.mmu.mfsrin) {
 137                                 u32 sr;
 138                                 sr = vcpu->arch.mmu.mfsrin(vcpu, srnum);
 139                                 kvmppc_set_gpr(vcpu, rt, sr);
 140                         }
 141                         break;
 142                 }
 143                 case OP_31_XOP_MFSRIN:
 144                 {
 145                         int srnum;
 146
 147                         srnum = (kvmppc_get_gpr(vcpu, rb) >> 28) & 0xf;
 148                         if (vcpu->arch.mmu.mfsrin) {
 149                                 u32 sr;
 150                                 sr = vcpu->arch.mmu.mfsrin(vcpu, srnum);
 151                                 kvmppc_set_gpr(vcpu, rt, sr);
 152                         }
 153                         break;
 154                 }
 155                 case OP_31_XOP_MTSR:
 156                         vcpu->arch.mmu.mtsrin(vcpu,
 157                                 (inst >> 16) & 0xf,
 158                                 kvmppc_get_gpr(vcpu, rs));
 159                         break;
 160                 case OP_31_XOP_MTSRIN:
 161                         vcpu->arch.mmu.mtsrin(vcpu,
 162                                 (kvmppc_get_gpr(vcpu, rb) >> 28) & 0xf,
 163                                 kvmppc_get_gpr(vcpu, rs));
 164                         break;
 165                 case OP_31_XOP_TLBIE:
 166                 case OP_31_XOP_TLBIEL:
 167                 {
 168                         bool large = (inst & 0x00200000) ? true : false;
 169                         ulong addr = kvmppc_get_gpr(vcpu, rb);
 170                         vcpu->arch.mmu.tlbie(vcpu, addr, large);
 171                         break;
 172                 }
 173                 case OP_31_XOP_EIOIO:
 174                         break;
 175                 case OP_31_XOP_SLBMTE:
 176                         if (!vcpu->arch.mmu.slbmte)
 177                                 return EMULATE_FAIL;
 178
 179                         vcpu->arch.mmu.slbmte(vcpu,
 180                                         kvmppc_get_gpr(vcpu, rs),
 181                                         kvmppc_get_gpr(vcpu, rb));
 182                         break;
 183                 case OP_31_XOP_SLBIE:
 184                         if (!vcpu->arch.mmu.slbie)
 185                                 return EMULATE_FAIL;
 186
 187                         vcpu->arch.mmu.slbie(vcpu,
 188                                         kvmppc_get_gpr(vcpu, rb));
 189                         break;
 190                 case OP_31_XOP_SLBIA:
 191                         if (!vcpu->arch.mmu.slbia)
 192                                 return EMULATE_FAIL;
 193
 194                         vcpu->arch.mmu.slbia(vcpu);
 195                         break;
 196                 case OP_31_XOP_SLBMFEE:
 197                         if (!vcpu->arch.mmu.slbmfee) {
 198                                 emulated = EMULATE_FAIL;
 199                         } else {
 200                                 ulong t, rb_val;
 201
 202                                 rb_val = kvmppc_get_gpr(vcpu, rb);
 203                                 t = vcpu->arch.mmu.slbmfee(vcpu, rb_val);
 204                                 kvmppc_set_gpr(vcpu, rt, t);
 205                         }
 206                         break;
 207                 case OP_31_XOP_SLBMFEV:
 208                         if (!vcpu->arch.mmu.slbmfev) {
 209                                 emulated = EMULATE_FAIL;
 210                         } else {
 211                                 ulong t, rb_val;
 212
 213                                 rb_val = kvmppc_get_gpr(vcpu, rb);
 214                                 t = vcpu->arch.mmu.slbmfev(vcpu, rb_val);
 215                                 kvmppc_set_gpr(vcpu, rt, t);
 216                         }
 217                         break;
 218                 case OP_31_XOP_DCBA:
 219                         /* Gets treated as NOP */
 220                         break;
 221                 case OP_31_XOP_DCBZ:
 222                 {
 223                         ulong rb_val = kvmppc_get_gpr(vcpu, rb);
 224                         ulong ra_val = 0;
 225                         ulong addr, vaddr;
 226                         u32 zeros[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
 227                         u32 dsisr;
 228                         int r;
 229
 230                         if (ra)
 231                                 ra_val = kvmppc_get_gpr(vcpu, ra);
 232
 233                         addr = (ra_val + rb_val) & ~31ULL;
 234                         if (!(vcpu->arch.shared->msr & MSR_SF))
 235                                 addr &= 0xffffffff;
 236                         vaddr = addr;
 237
 238                         r = kvmppc_st(vcpu, &addr, 32, zeros, true);
 239                         if ((r == -ENOENT) || (r == -EPERM)) {
 240                                 struct kvmppc_book3s_shadow_vcpu *svcpu;
 241
 242                                 svcpu = svcpu_get(vcpu);
 243                                 *advance = 0;
 244                                 vcpu->arch.shared->dar = vaddr;
 245                                 svcpu->fault_dar = vaddr;
 246
 247                                 dsisr = DSISR_ISSTORE;
 248                                 if (r == -ENOENT)
 249                                         dsisr |= DSISR_NOHPTE;
 250                                 else if (r == -EPERM)
 251                                         dsisr |= DSISR_PROTFAULT;
 252
 253                                 vcpu->arch.shared->dsisr = dsisr;
 254                                 svcpu->fault_dsisr = dsisr;
 255                                 svcpu_put(svcpu);
 256
 257                                 kvmppc_book3s_queue_irqprio(vcpu,
 258                                         BOOK3S_INTERRUPT_DATA_STORAGE);
 259                         }
 260
 261                         break;
 262                 }
 263                 default:
 264                         emulated = EMULATE_FAIL;
 265                 }
 266                 break;
 267         default:
 268                 emulated = EMULATE_FAIL;
 269         }
 270
 271         if (emulated == EMULATE_FAIL)
 272                 emulated = kvmppc_emulate_paired_single(run, vcpu);
 273
 274         return emulated;
 275 }
 276
 277 void kvmppc_set_bat(struct kvm_vcpu *vcpu, struct kvmppc_bat *bat, bool upper,
 278                     u32 val)
 279 {
 280         if (upper) {
 281                 /* Upper BAT */
 282                 u32 bl = (val >> 2) & 0x7ff;
 283                 bat->bepi_mask = (~bl << 17);
 284                 bat->bepi = val & 0xfffe0000;
 285                 bat->vs = (val & 2) ? 1 : 0;
 286                 bat->vp = (val & 1) ? 1 : 0;
 287                 bat->raw = (bat->raw & 0xffffffff00000000ULL) | val;
 288         } else {
 289                 /* Lower BAT */
 290                 bat->brpn = val & 0xfffe0000;
 291                 bat->wimg = (val >> 3) & 0xf;
 292                 bat->pp = val & 3;
 293                 bat->raw = (bat->raw & 0x00000000ffffffffULL) | ((u64)val << 32);
 294         }
 295 }
 296
 297 static struct kvmppc_bat *kvmppc_find_bat(struct kvm_vcpu *vcpu, int sprn)
 298 {
 299         struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 300         struct kvmppc_bat *bat;
 301
 302         switch (sprn) {
 303         case SPRN_IBAT0U ... SPRN_IBAT3L:
 304                 bat = &vcpu_book3s->ibat[(sprn - SPRN_IBAT0U) / 2];
 305                 break;
 306         case SPRN_IBAT4U ... SPRN_IBAT7L:
 307                 bat = &vcpu_book3s->ibat[4 + ((sprn - SPRN_IBAT4U) / 2)];
 308                 break;
 309         case SPRN_DBAT0U ... SPRN_DBAT3L:
 310                 bat = &vcpu_book3s->dbat[(sprn - SPRN_DBAT0U) / 2];
 311                 break;
 312         case SPRN_DBAT4U ... SPRN_DBAT7L:
 313                 bat = &vcpu_book3s->dbat[4 + ((sprn - SPRN_DBAT4U) / 2)];
 314                 break;
 315         default:
 316                 BUG();
 317         }
 318
 319         return bat;
 320 }
 321
 322 int kvmppc_core_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, ulong spr_val)
 323 {
 324         int emulated = EMULATE_DONE;
 325
 326         switch (sprn) {
 327         case SPRN_SDR1:
 328                 if (!spr_allowed(vcpu, PRIV_HYPER))
 329                         goto unprivileged;
 330                 to_book3s(vcpu)->sdr1 = spr_val;
 331                 break;
 332         case SPRN_DSISR:
 333                 vcpu->arch.shared->dsisr = spr_val;
 334                 break;
 335         case SPRN_DAR:
 336                 vcpu->arch.shared->dar = spr_val;
 337                 break;
 338         case SPRN_HIOR:
 339                 to_book3s(vcpu)->hior = spr_val;
 340                 break;
 341         case SPRN_IBAT0U ... SPRN_IBAT3L:
 342         case SPRN_IBAT4U ... SPRN_IBAT7L:
 343         case SPRN_DBAT0U ... SPRN_DBAT3L:
 344         case SPRN_DBAT4U ... SPRN_DBAT7L:
 345         {
 346                 struct kvmppc_bat *bat = kvmppc_find_bat(vcpu, sprn);
 347
 348                 kvmppc_set_bat(vcpu, bat, !(sprn % 2), (u32)spr_val);
 349                 /* BAT writes happen so rarely that we're ok to flush
 350                  * everything here */
 351                 kvmppc_mmu_pte_flush(vcpu, 0, 0);
 352                 kvmppc_mmu_flush_segments(vcpu);
 353                 break;
 354         }
 355         case SPRN_HID0:
 356                 to_book3s(vcpu)->hid[0] = spr_val;
 357                 break;
 358         case SPRN_HID1:
 359                 to_book3s(vcpu)->hid[1] = spr_val;
 360                 break;
 361         case SPRN_HID2:
 362                 to_book3s(vcpu)->hid[2] = spr_val;
 363                 break;
 364         case SPRN_HID2_GEKKO:
 365                 to_book3s(vcpu)->hid[2] = spr_val;
 366                 /* HID2.PSE controls paired single on gekko */
 367                 switch (vcpu->arch.pvr) {
 368                 case 0x00080200:        /* lonestar 2.0 */
 369                 case 0x00088202:        /* lonestar 2.2 */
 370                 case 0x70000100:        /* gekko 1.0 */
 371                 case 0x00080100:        /* gekko 2.0 */
 372                 case 0x00083203:        /* gekko 2.3a */
 373                 case 0x00083213:        /* gekko 2.3b */
 374                 case 0x00083204:        /* gekko 2.4 */
 375                 case 0x00083214:        /* gekko 2.4e (8SE) - retail HW2 */
 376                 case 0x00087200:        /* broadway */
 377                         if (vcpu->arch.hflags & BOOK3S_HFLAG_NATIVE_PS) {
 378                                 /* Native paired singles */
 379                         } else if (spr_val & (1 << 29)) { /* HID2.PSE */
 380                                 vcpu->arch.hflags |= BOOK3S_HFLAG_PAIRED_SINGLE;
 381                                 kvmppc_giveup_ext(vcpu, MSR_FP);
 382                         } else {
 383                                 vcpu->arch.hflags &= ~BOOK3S_HFLAG_PAIRED_SINGLE;
 384                         }
 385                         break;
 386                 }
 387                 break;
 388         case SPRN_HID4:
 389         case SPRN_HID4_GEKKO:
 390                 to_book3s(vcpu)->hid[4] = spr_val;
 391                 break;
 392         case SPRN_HID5:
 393                 to_book3s(vcpu)->hid[5] = spr_val;
 394                 /* guest HID5 set can change is_dcbz32 */
 395                 if (vcpu->arch.mmu.is_dcbz32(vcpu) &&
 396                     (mfmsr() & MSR_HV))
 397                         vcpu->arch.hflags |= BOOK3S_HFLAG_DCBZ32;
 398                 break;
 399         case SPRN_PURR:
 400                 to_book3s(vcpu)->purr_offset = spr_val - get_tb();
 401                 break;
 402         case SPRN_SPURR:
 403                 to_book3s(vcpu)->spurr_offset = spr_val - get_tb();
 404                 break;
 405         case SPRN_GQR0:
 406         case SPRN_GQR1:
 407         case SPRN_GQR2:
 408         case SPRN_GQR3:
 409         case SPRN_GQR4:
 410         case SPRN_GQR5:
 411         case SPRN_GQR6:
 412         case SPRN_GQR7:
 413                 to_book3s(vcpu)->gqr[sprn - SPRN_GQR0] = spr_val;
 414                 break;
 415         case SPRN_ICTC:
 416         case SPRN_THRM1:
 417         case SPRN_THRM2:
 418         case SPRN_THRM3:
 419         case SPRN_CTRLF:
 420         case SPRN_CTRLT:
 421         case SPRN_L2CR:
 422         case SPRN_DSCR:
 423         case SPRN_MMCR0_GEKKO:
 424         case SPRN_MMCR1_GEKKO:
 425         case SPRN_PMC1_GEKKO:
 426         case SPRN_PMC2_GEKKO:
 427         case SPRN_PMC3_GEKKO:
 428         case SPRN_PMC4_GEKKO:
 429         case SPRN_WPAR_GEKKO:
 430                 break;
 431 unprivileged:
 432         default:
 433                 printk(KERN_INFO "KVM: invalid SPR write: %d\n", sprn);
 434 #ifndef DEBUG_SPR
 435                 emulated = EMULATE_FAIL;
 436 #endif
 437                 break;
 438         }
 439
 440         return emulated;
 441 }
 442
 443 int kvmppc_core_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, ulong *spr_val)
 444 {
 445         int emulated = EMULATE_DONE;
 446
 447         switch (sprn) {
 448         case SPRN_IBAT0U ... SPRN_IBAT3L:
 449         case SPRN_IBAT4U ... SPRN_IBAT7L:
 450         case SPRN_DBAT0U ... SPRN_DBAT3L:
 451         case SPRN_DBAT4U ... SPRN_DBAT7L:
 452         {
 453                 struct kvmppc_bat *bat = kvmppc_find_bat(vcpu, sprn);
 454
 455                 if (sprn % 2)
 456                         *spr_val = bat->raw >> 32;
 457                 else
 458                         *spr_val = bat->raw;
 459
 460                 break;
 461         }
 462         case SPRN_SDR1:
 463                 if (!spr_allowed(vcpu, PRIV_HYPER))
 464                         goto unprivileged;
 465                 *spr_val = to_book3s(vcpu)->sdr1;
 466                 break;
 467         case SPRN_DSISR:
 468                 *spr_val = vcpu->arch.shared->dsisr;
 469                 break;
 470         case SPRN_DAR:
 471                 *spr_val = vcpu->arch.shared->dar;
 472                 break;
 473         case SPRN_HIOR:
 474                 *spr_val = to_book3s(vcpu)->hior;
 475                 break;
 476         case SPRN_HID0:
 477                 *spr_val = to_book3s(vcpu)->hid[0];
 478                 break;
 479         case SPRN_HID1:
 480                 *spr_val = to_book3s(vcpu)->hid[1];
 481                 break;
 482         case SPRN_HID2:
 483         case SPRN_HID2_GEKKO:
 484                 *spr_val = to_book3s(vcpu)->hid[2];
 485                 break;
 486         case SPRN_HID4:
 487         case SPRN_HID4_GEKKO:
 488                 *spr_val = to_book3s(vcpu)->hid[4];
 489                 break;
 490         case SPRN_HID5:
 491                 *spr_val = to_book3s(vcpu)->hid[5];
 492                 break;
 493         case SPRN_CFAR:
 494         case SPRN_DSCR:
 495                 *spr_val = 0;
 496                 break;
 497         case SPRN_PURR:
 498                 *spr_val = get_tb() + to_book3s(vcpu)->purr_offset;
 499                 break;
 500         case SPRN_SPURR:
 501                 *spr_val = get_tb() + to_book3s(vcpu)->purr_offset;
 502                 break;
 503         case SPRN_GQR0:
 504         case SPRN_GQR1:
 505         case SPRN_GQR2:
 506         case SPRN_GQR3:
 507         case SPRN_GQR4:
 508         case SPRN_GQR5:
 509         case SPRN_GQR6:
 510         case SPRN_GQR7:
 511                 *spr_val = to_book3s(vcpu)->gqr[sprn - SPRN_GQR0];
 512                 break;
 513         case SPRN_THRM1:
 514         case SPRN_THRM2:
 515         case SPRN_THRM3:
 516         case SPRN_CTRLF:
 517         case SPRN_CTRLT:
 518         case SPRN_L2CR:
 519         case SPRN_MMCR0_GEKKO:
 520         case SPRN_MMCR1_GEKKO:
 521         case SPRN_PMC1_GEKKO:
 522         case SPRN_PMC2_GEKKO:
 523         case SPRN_PMC3_GEKKO:
 524         case SPRN_PMC4_GEKKO:
 525         case SPRN_WPAR_GEKKO:
 526                 *spr_val = 0;
 527                 break;
 528         default:
 529 unprivileged:
 530                 printk(KERN_INFO "KVM: invalid SPR read: %d\n", sprn);
 531 #ifndef DEBUG_SPR
 532                 emulated = EMULATE_FAIL;
 533 #endif
 534                 break;
 535         }
 536
 537         return emulated;
 538 }
 539
 540 u32 kvmppc_alignment_dsisr(struct kvm_vcpu *vcpu, unsigned int inst)
 541 {
 542         u32 dsisr = 0;
 543
 544         /*
 545          * This is what the spec says about DSISR bits (not mentioned = 0):
 546          *
 547          * 12:13                [DS]    Set to bits 30:31
 548          * 15:16                [X]     Set to bits 29:30
 549          * 17                   [X]     Set to bit 25
 550          *                      [D/DS]  Set to bit 5
 551          * 18:21                [X]     Set to bits 21:24
 552          *                      [D/DS]  Set to bits 1:4
 553          * 22:26                        Set to bits 6:10 (RT/RS/FRT/FRS)
 554          * 27:31                        Set to bits 11:15 (RA)
 555          */
 556
 557         switch (get_op(inst)) {
 558         /* D-form */
 559         case OP_LFS:
 560         case OP_LFD:
 561         case OP_STFD:
 562         case OP_STFS:
 563                 dsisr |= (inst >> 12) & 0x4000; /* bit 17 */
 564                 dsisr |= (inst >> 17) & 0x3c00; /* bits 18:21 */
 565                 break;
 566         /* X-form */
 567         case 31:
 568                 dsisr |= (inst << 14) & 0x18000; /* bits 15:16 */
 569                 dsisr |= (inst << 8)  & 0x04000; /* bit 17 */
 570                 dsisr |= (inst << 3)  & 0x03c00; /* bits 18:21 */
 571                 break;
 572         default:
 573                 printk(KERN_INFO "KVM: Unaligned instruction 0x%x\n", inst);
 574                 break;
 575         }
 576
 577         dsisr |= (inst >> 16) & 0x03ff; /* bits 22:31 */
 578
 579         return dsisr;
 580 }
 581
 582 ulong kvmppc_alignment_dar(struct kvm_vcpu *vcpu, unsigned int inst)
 583 {
 584         ulong dar = 0;
 585         ulong ra = get_ra(inst);
 586         ulong rb = get_rb(inst);
 587
 588         switch (get_op(inst)) {
 589         case OP_LFS:
 590         case OP_LFD:
 591         case OP_STFD:
 592         case OP_STFS:
 593                 if (ra)
 594                         dar = kvmppc_get_gpr(vcpu, ra);
 595                 dar += (s32)((s16)inst);
 596                 break;
 597         case 31:
 598                 if (ra)
 599                         dar = kvmppc_get_gpr(vcpu, ra);
 600                 dar += kvmppc_get_gpr(vcpu, rb);
 601                 break;
 602         default:
 603                 printk(KERN_INFO "KVM: Unaligned instruction 0x%x\n", inst);
 604                 break;
 605         }
 606
 607         return dar;
 608 }