arch/s390/kvm/intercept.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * in-kernel handling for sie intercepts
   4  *
   5  * Copyright IBM Corp. 2008, 2020
   6  *
   7  *    Author(s): Carsten Otte <cotte@de.ibm.com>
   8  *               Christian Borntraeger <borntraeger@de.ibm.com>
   9  */
  10
  11 #include <linux/kvm_host.h>
  12 #include <linux/errno.h>
  13 #include <linux/pagemap.h>
  14
  15 #include <asm/asm-offsets.h>
  16 #include <asm/irq.h>
  17 #include <asm/sysinfo.h>
  18 #include <asm/uv.h>
  19
  20 #include "kvm-s390.h"
  21 #include "gaccess.h"
  22 #include "trace.h"
  23 #include "trace-s390.h"
  24
  25 u8 kvm_s390_get_ilen(struct kvm_vcpu *vcpu)
  26 {
  27         struct kvm_s390_sie_block *sie_block = vcpu->arch.sie_block;
  28         u8 ilen = 0;
  29
  30         switch (vcpu->arch.sie_block->icptcode) {
  31         case ICPT_INST:
  32         case ICPT_INSTPROGI:
  33         case ICPT_OPEREXC:
  34         case ICPT_PARTEXEC:
  35         case ICPT_IOINST:
  36                 /* instruction only stored for these icptcodes */
  37                 ilen = insn_length(vcpu->arch.sie_block->ipa >> 8);
  38                 /* Use the length of the EXECUTE instruction if necessary */
  39                 if (sie_block->icptstatus & 1) {
  40                         ilen = (sie_block->icptstatus >> 4) & 0x6;
  41                         if (!ilen)
  42                                 ilen = 4;
  43                 }
  44                 break;
  45         case ICPT_PROGI:
  46                 /* bit 1+2 of pgmilc are the ilc, so we directly get ilen */
  47                 ilen = vcpu->arch.sie_block->pgmilc & 0x6;
  48                 break;
  49         }
  50         return ilen;
  51 }
  52
  53 static int handle_stop(struct kvm_vcpu *vcpu)
  54 {
  55         struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
  56         int rc = 0;
  57         uint8_t flags, stop_pending;
  58
  59         vcpu->stat.exit_stop_request++;
  60
  61         /* delay the stop if any non-stop irq is pending */
  62         if (kvm_s390_vcpu_has_irq(vcpu, 1))
  63                 return 0;
  64
  65         /* avoid races with the injection/SIGP STOP code */
  66         spin_lock(&li->lock);
  67         flags = li->irq.stop.flags;
  68         stop_pending = kvm_s390_is_stop_irq_pending(vcpu);
  69         spin_unlock(&li->lock);
  70
  71         trace_kvm_s390_stop_request(stop_pending, flags);
  72         if (!stop_pending)
  73                 return 0;
  74
  75         if (flags & KVM_S390_STOP_FLAG_STORE_STATUS) {
  76                 rc = kvm_s390_vcpu_store_status(vcpu,
  77                                                 KVM_S390_STORE_STATUS_NOADDR);
  78                 if (rc)
  79                         return rc;
  80         }
  81
  82         /*
  83          * no need to check the return value of vcpu_stop as it can only have
  84          * an error for protvirt, but protvirt means user cpu state
  85          */
  86         if (!kvm_s390_user_cpu_state_ctrl(vcpu->kvm))
  87                 kvm_s390_vcpu_stop(vcpu);
  88         return -EOPNOTSUPP;
  89 }
  90
  91 static int handle_validity(struct kvm_vcpu *vcpu)
  92 {
  93         int viwhy = vcpu->arch.sie_block->ipb >> 16;
  94
  95         vcpu->stat.exit_validity++;
  96         trace_kvm_s390_intercept_validity(vcpu, viwhy);
  97         KVM_EVENT(3, "validity intercept 0x%x for pid %u (kvm 0x%pK)", viwhy,
  98                   current->pid, vcpu->kvm);
  99
 100         /* do not warn on invalid runtime instrumentation mode */
 101         WARN_ONCE(viwhy != 0x44, "kvm: unhandled validity intercept 0x%x\n",
 102                   viwhy);
 103         return -EINVAL;
 104 }
 105
 106 static int handle_instruction(struct kvm_vcpu *vcpu)
 107 {
 108         vcpu->stat.exit_instruction++;
 109         trace_kvm_s390_intercept_instruction(vcpu,
 110                                              vcpu->arch.sie_block->ipa,
 111                                              vcpu->arch.sie_block->ipb);
 112
 113         switch (vcpu->arch.sie_block->ipa >> 8) {
 114         case 0x01:
 115                 return kvm_s390_handle_01(vcpu);
 116         case 0x82:
 117                 return kvm_s390_handle_lpsw(vcpu);
 118         case 0x83:
 119                 return kvm_s390_handle_diag(vcpu);
 120         case 0xaa:
 121                 return kvm_s390_handle_aa(vcpu);
 122         case 0xae:
 123                 return kvm_s390_handle_sigp(vcpu);
 124         case 0xb2:
 125                 return kvm_s390_handle_b2(vcpu);
 126         case 0xb6:
 127                 return kvm_s390_handle_stctl(vcpu);
 128         case 0xb7:
 129                 return kvm_s390_handle_lctl(vcpu);
 130         case 0xb9:
 131                 return kvm_s390_handle_b9(vcpu);
 132         case 0xe3:
 133                 return kvm_s390_handle_e3(vcpu);
 134         case 0xe5:
 135                 return kvm_s390_handle_e5(vcpu);
 136         case 0xeb:
 137                 return kvm_s390_handle_eb(vcpu);
 138         default:
 139                 return -EOPNOTSUPP;
 140         }
 141 }
 142
 143 static int inject_prog_on_prog_intercept(struct kvm_vcpu *vcpu)
 144 {
 145         struct kvm_s390_pgm_info pgm_info = {
 146                 .code = vcpu->arch.sie_block->iprcc,
 147                 /* the PSW has already been rewound */
 148                 .flags = KVM_S390_PGM_FLAGS_NO_REWIND,
 149         };
 150
 151         switch (vcpu->arch.sie_block->iprcc & ~PGM_PER) {
 152         case PGM_AFX_TRANSLATION:
 153         case PGM_ASX_TRANSLATION:
 154         case PGM_EX_TRANSLATION:
 155         case PGM_LFX_TRANSLATION:
 156         case PGM_LSTE_SEQUENCE:
 157         case PGM_LSX_TRANSLATION:
 158         case PGM_LX_TRANSLATION:
 159         case PGM_PRIMARY_AUTHORITY:
 160         case PGM_SECONDARY_AUTHORITY:
 161         case PGM_SPACE_SWITCH:
 162                 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
 163                 break;
 164         case PGM_ALEN_TRANSLATION:
 165         case PGM_ALE_SEQUENCE:
 166         case PGM_ASTE_INSTANCE:
 167         case PGM_ASTE_SEQUENCE:
 168         case PGM_ASTE_VALIDITY:
 169         case PGM_EXTENDED_AUTHORITY:
 170                 pgm_info.exc_access_id = vcpu->arch.sie_block->eai;
 171                 break;
 172         case PGM_ASCE_TYPE:
 173         case PGM_PAGE_TRANSLATION:
 174         case PGM_REGION_FIRST_TRANS:
 175         case PGM_REGION_SECOND_TRANS:
 176         case PGM_REGION_THIRD_TRANS:
 177         case PGM_SEGMENT_TRANSLATION:
 178                 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
 179                 pgm_info.exc_access_id  = vcpu->arch.sie_block->eai;
 180                 pgm_info.op_access_id  = vcpu->arch.sie_block->oai;
 181                 break;
 182         case PGM_MONITOR:
 183                 pgm_info.mon_class_nr = vcpu->arch.sie_block->mcn;
 184                 pgm_info.mon_code = vcpu->arch.sie_block->tecmc;
 185                 break;
 186         case PGM_VECTOR_PROCESSING:
 187         case PGM_DATA:
 188                 pgm_info.data_exc_code = vcpu->arch.sie_block->dxc;
 189                 break;
 190         case PGM_PROTECTION:
 191                 pgm_info.trans_exc_code = vcpu->arch.sie_block->tecmc;
 192                 pgm_info.exc_access_id  = vcpu->arch.sie_block->eai;
 193                 break;
 194         default:
 195                 break;
 196         }
 197
 198         if (vcpu->arch.sie_block->iprcc & PGM_PER) {
 199                 pgm_info.per_code = vcpu->arch.sie_block->perc;
 200                 pgm_info.per_atmid = vcpu->arch.sie_block->peratmid;
 201                 pgm_info.per_address = vcpu->arch.sie_block->peraddr;
 202                 pgm_info.per_access_id = vcpu->arch.sie_block->peraid;
 203         }
 204         return kvm_s390_inject_prog_irq(vcpu, &pgm_info);
 205 }
 206
 207 /*
 208  * restore ITDB to program-interruption TDB in guest lowcore
 209  * and set TX abort indication if required
 210 */
 211 static int handle_itdb(struct kvm_vcpu *vcpu)
 212 {
 213         struct kvm_s390_itdb *itdb;
 214         int rc;
 215
 216         if (!IS_TE_ENABLED(vcpu) || !IS_ITDB_VALID(vcpu))
 217                 return 0;
 218         if (current->thread.per_flags & PER_FLAG_NO_TE)
 219                 return 0;
 220         itdb = phys_to_virt(vcpu->arch.sie_block->itdba);
 221         rc = write_guest_lc(vcpu, __LC_PGM_TDB, itdb, sizeof(*itdb));
 222         if (rc)
 223                 return rc;
 224         memset(itdb, 0, sizeof(*itdb));
 225
 226         return 0;
 227 }
 228
 229 #define per_event(vcpu) (vcpu->arch.sie_block->iprcc & PGM_PER)
 230
 231 static bool should_handle_per_event(const struct kvm_vcpu *vcpu)
 232 {
 233         if (!guestdbg_enabled(vcpu) || !per_event(vcpu))
 234                 return false;
 235         if (guestdbg_sstep_enabled(vcpu) &&
 236             vcpu->arch.sie_block->iprcc != PGM_PER) {
 237                 /*
 238                  * __vcpu_run() will exit after delivering the concurrently
 239                  * indicated condition.
 240                  */
 241                 return false;
 242         }
 243         return true;
 244 }
 245
 246 static int handle_prog(struct kvm_vcpu *vcpu)
 247 {
 248         psw_t psw;
 249         int rc;
 250
 251         vcpu->stat.exit_program_interruption++;
 252
 253         /*
 254          * Intercept 8 indicates a loop of specification exceptions
 255          * for protected guests.
 256          */
 257         if (kvm_s390_pv_cpu_is_protected(vcpu))
 258                 return -EOPNOTSUPP;
 259
 260         if (should_handle_per_event(vcpu)) {
 261                 rc = kvm_s390_handle_per_event(vcpu);
 262                 if (rc)
 263                         return rc;
 264                 /* the interrupt might have been filtered out completely */
 265                 if (vcpu->arch.sie_block->iprcc == 0)
 266                         return 0;
 267         }
 268
 269         trace_kvm_s390_intercept_prog(vcpu, vcpu->arch.sie_block->iprcc);
 270         if (vcpu->arch.sie_block->iprcc == PGM_SPECIFICATION) {
 271                 rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &psw, sizeof(psw_t));
 272                 if (rc)
 273                         return rc;
 274                 /* Avoid endless loops of specification exceptions */
 275                 if (!is_valid_psw(&psw))
 276                         return -EOPNOTSUPP;
 277         }
 278         rc = handle_itdb(vcpu);
 279         if (rc)
 280                 return rc;
 281
 282         return inject_prog_on_prog_intercept(vcpu);
 283 }
 284
 285 /**
 286  * handle_external_interrupt - used for external interruption interceptions
 287  * @vcpu: virtual cpu
 288  *
 289  * This interception occurs if:
 290  * - the CPUSTAT_EXT_INT bit was already set when the external interrupt
 291  *   occurred. In this case, the interrupt needs to be injected manually to
 292  *   preserve interrupt priority.
 293  * - the external new PSW has external interrupts enabled, which will cause an
 294  *   interruption loop. We drop to userspace in this case.
 295  *
 296  * The latter case can be detected by inspecting the external mask bit in the
 297  * external new psw.
 298  *
 299  * Under PV, only the latter case can occur, since interrupt priorities are
 300  * handled in the ultravisor.
 301  */
 302 static int handle_external_interrupt(struct kvm_vcpu *vcpu)
 303 {
 304         u16 eic = vcpu->arch.sie_block->eic;
 305         struct kvm_s390_irq irq;
 306         psw_t newpsw;
 307         int rc;
 308
 309         vcpu->stat.exit_external_interrupt++;
 310
 311         if (kvm_s390_pv_cpu_is_protected(vcpu)) {
 312                 newpsw = vcpu->arch.sie_block->gpsw;
 313         } else {
 314                 rc = read_guest_lc(vcpu, __LC_EXT_NEW_PSW, &newpsw, sizeof(psw_t));
 315                 if (rc)
 316                         return rc;
 317         }
 318
 319         /*
 320          * Clock comparator or timer interrupt with external interrupt enabled
 321          * will cause interrupt loop. Drop to userspace.
 322          */
 323         if ((eic == EXT_IRQ_CLK_COMP || eic == EXT_IRQ_CPU_TIMER) &&
 324             (newpsw.mask & PSW_MASK_EXT))
 325                 return -EOPNOTSUPP;
 326
 327         switch (eic) {
 328         case EXT_IRQ_CLK_COMP:
 329                 irq.type = KVM_S390_INT_CLOCK_COMP;
 330                 break;
 331         case EXT_IRQ_CPU_TIMER:
 332                 irq.type = KVM_S390_INT_CPU_TIMER;
 333                 break;
 334         case EXT_IRQ_EXTERNAL_CALL:
 335                 irq.type = KVM_S390_INT_EXTERNAL_CALL;
 336                 irq.u.extcall.code = vcpu->arch.sie_block->extcpuaddr;
 337                 rc = kvm_s390_inject_vcpu(vcpu, &irq);
 338                 /* ignore if another external call is already pending */
 339                 if (rc == -EBUSY)
 340                         return 0;
 341                 return rc;
 342         default:
 343                 return -EOPNOTSUPP;
 344         }
 345
 346         return kvm_s390_inject_vcpu(vcpu, &irq);
 347 }
 348
 349 /**
 350  * handle_mvpg_pei - Handle MOVE PAGE partial execution interception.
 351  * @vcpu: virtual cpu
 352  *
 353  * This interception can only happen for guests with DAT disabled and
 354  * addresses that are currently not mapped in the host. Thus we try to
 355  * set up the mappings for the corresponding user pages here (or throw
 356  * addressing exceptions in case of illegal guest addresses).
 357  */
 358 static int handle_mvpg_pei(struct kvm_vcpu *vcpu)
 359 {
 360         unsigned long srcaddr, dstaddr;
 361         int reg1, reg2, rc;
 362
 363         kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);
 364
 365         /* Ensure that the source is paged-in, no actual access -> no key checking */
 366         rc = guest_translate_address_with_key(vcpu, vcpu->run->s.regs.gprs[reg2],
 367                                               reg2, &srcaddr, GACC_FETCH, 0);
 368         if (rc)
 369                 return kvm_s390_inject_prog_cond(vcpu, rc);
 370         rc = kvm_arch_fault_in_page(vcpu, srcaddr, 0);
 371         if (rc != 0)
 372                 return rc;
 373
 374         /* Ensure that the source is paged-in, no actual access -> no key checking */
 375         rc = guest_translate_address_with_key(vcpu, vcpu->run->s.regs.gprs[reg1],
 376                                               reg1, &dstaddr, GACC_STORE, 0);
 377         if (rc)
 378                 return kvm_s390_inject_prog_cond(vcpu, rc);
 379         rc = kvm_arch_fault_in_page(vcpu, dstaddr, 1);
 380         if (rc != 0)
 381                 return rc;
 382
 383         kvm_s390_retry_instr(vcpu);
 384
 385         return 0;
 386 }
 387
 388 static int handle_partial_execution(struct kvm_vcpu *vcpu)
 389 {
 390         vcpu->stat.exit_pei++;
 391
 392         if (vcpu->arch.sie_block->ipa == 0xb254)        /* MVPG */
 393                 return handle_mvpg_pei(vcpu);
 394         if (vcpu->arch.sie_block->ipa >> 8 == 0xae)     /* SIGP */
 395                 return kvm_s390_handle_sigp_pei(vcpu);
 396
 397         return -EOPNOTSUPP;
 398 }
 399
 400 /*
 401  * Handle the sthyi instruction that provides the guest with system
 402  * information, like current CPU resources available at each level of
 403  * the machine.
 404  */
 405 int handle_sthyi(struct kvm_vcpu *vcpu)
 406 {
 407         int reg1, reg2, cc = 0, r = 0;
 408         u64 code, addr, rc = 0;
 409         struct sthyi_sctns *sctns = NULL;
 410
 411         if (!test_kvm_facility(vcpu->kvm, 74))
 412                 return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
 413
 414         kvm_s390_get_regs_rre(vcpu, &reg1, &reg2);
 415         code = vcpu->run->s.regs.gprs[reg1];
 416         addr = vcpu->run->s.regs.gprs[reg2];
 417
 418         vcpu->stat.instruction_sthyi++;
 419         VCPU_EVENT(vcpu, 3, "STHYI: fc: %llu addr: 0x%016llx", code, addr);
 420         trace_kvm_s390_handle_sthyi(vcpu, code, addr);
 421
 422         if (reg1 == reg2 || reg1 & 1 || reg2 & 1)
 423                 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
 424
 425         if (code & 0xffff) {
 426                 cc = 3;
 427                 rc = 4;
 428                 goto out;
 429         }
 430
 431         if (!kvm_s390_pv_cpu_is_protected(vcpu) && (addr & ~PAGE_MASK))
 432                 return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
 433
 434         sctns = (void *)get_zeroed_page(GFP_KERNEL_ACCOUNT);
 435         if (!sctns)
 436                 return -ENOMEM;
 437
 438         cc = sthyi_fill(sctns, &rc);
 439         if (cc < 0) {
 440                 free_page((unsigned long)sctns);
 441                 return cc;
 442         }
 443 out:
 444         if (!cc) {
 445                 if (kvm_s390_pv_cpu_is_protected(vcpu)) {
 446                         memcpy(sida_addr(vcpu->arch.sie_block), sctns, PAGE_SIZE);
 447                 } else {
 448                         r = write_guest(vcpu, addr, reg2, sctns, PAGE_SIZE);
 449                         if (r) {
 450                                 free_page((unsigned long)sctns);
 451                                 return kvm_s390_inject_prog_cond(vcpu, r);
 452                         }
 453                 }
 454         }
 455
 456         free_page((unsigned long)sctns);
 457         vcpu->run->s.regs.gprs[reg2 + 1] = rc;
 458         kvm_s390_set_psw_cc(vcpu, cc);
 459         return r;
 460 }
 461
 462 static int handle_operexc(struct kvm_vcpu *vcpu)
 463 {
 464         psw_t oldpsw, newpsw;
 465         int rc;
 466
 467         vcpu->stat.exit_operation_exception++;
 468         trace_kvm_s390_handle_operexc(vcpu, vcpu->arch.sie_block->ipa,
 469                                       vcpu->arch.sie_block->ipb);
 470
 471         if (vcpu->arch.sie_block->ipa == 0xb256)
 472                 return handle_sthyi(vcpu);
 473
 474         if (vcpu->arch.sie_block->ipa == 0 && vcpu->kvm->arch.user_instr0)
 475                 return -EOPNOTSUPP;
 476         rc = read_guest_lc(vcpu, __LC_PGM_NEW_PSW, &newpsw, sizeof(psw_t));
 477         if (rc)
 478                 return rc;
 479         /*
 480          * Avoid endless loops of operation exceptions, if the pgm new
 481          * PSW will cause a new operation exception.
 482          * The heuristic checks if the pgm new psw is within 6 bytes before
 483          * the faulting psw address (with same DAT, AS settings) and the
 484          * new psw is not a wait psw and the fault was not triggered by
 485          * problem state.
 486          */
 487         oldpsw = vcpu->arch.sie_block->gpsw;
 488         if (oldpsw.addr - newpsw.addr <= 6 &&
 489             !(newpsw.mask & PSW_MASK_WAIT) &&
 490             !(oldpsw.mask & PSW_MASK_PSTATE) &&
 491             (newpsw.mask & PSW_MASK_ASC) == (oldpsw.mask & PSW_MASK_ASC) &&
 492             (newpsw.mask & PSW_MASK_DAT) == (oldpsw.mask & PSW_MASK_DAT))
 493                 return -EOPNOTSUPP;
 494
 495         return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
 496 }
 497
 498 static int handle_pv_spx(struct kvm_vcpu *vcpu)
 499 {
 500         u32 pref = *(u32 *)sida_addr(vcpu->arch.sie_block);
 501
 502         kvm_s390_set_prefix(vcpu, pref);
 503         trace_kvm_s390_handle_prefix(vcpu, 1, pref);
 504         return 0;
 505 }
 506
 507 static int handle_pv_sclp(struct kvm_vcpu *vcpu)
 508 {
 509         struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 510
 511         spin_lock(&fi->lock);
 512         /*
 513          * 2 cases:
 514          * a: an sccb answering interrupt was already pending or in flight.
 515          *    As the sccb value is not known we can simply set some value to
 516          *    trigger delivery of a saved SCCB. UV will then use its saved
 517          *    copy of the SCCB value.
 518          * b: an error SCCB interrupt needs to be injected so we also inject
 519          *    a fake SCCB address. Firmware will use the proper one.
 520          * This makes sure, that both errors and real sccb returns will only
 521          * be delivered after a notification intercept (instruction has
 522          * finished) but not after others.
 523          */
 524         fi->srv_signal.ext_params |= 0x43000;
 525         set_bit(IRQ_PEND_EXT_SERVICE, &fi->pending_irqs);
 526         clear_bit(IRQ_PEND_EXT_SERVICE, &fi->masked_irqs);
 527         spin_unlock(&fi->lock);
 528         return 0;
 529 }
 530
 531 static int handle_pv_uvc(struct kvm_vcpu *vcpu)
 532 {
 533         struct uv_cb_share *guest_uvcb = sida_addr(vcpu->arch.sie_block);
 534         struct uv_cb_cts uvcb = {
 535                 .header.cmd     = UVC_CMD_UNPIN_PAGE_SHARED,
 536                 .header.len     = sizeof(uvcb),
 537                 .guest_handle   = kvm_s390_pv_get_handle(vcpu->kvm),
 538                 .gaddr          = guest_uvcb->paddr,
 539         };
 540         int rc;
 541
 542         if (guest_uvcb->header.cmd != UVC_CMD_REMOVE_SHARED_ACCESS) {
 543                 WARN_ONCE(1, "Unexpected notification intercept for UVC 0x%x\n",
 544                           guest_uvcb->header.cmd);
 545                 return 0;
 546         }
 547         rc = gmap_make_secure(vcpu->arch.gmap, uvcb.gaddr, &uvcb);
 548         /*
 549          * If the unpin did not succeed, the guest will exit again for the UVC
 550          * and we will retry the unpin.
 551          */
 552         if (rc == -EINVAL)
 553                 return 0;
 554         /*
 555          * If we got -EAGAIN here, we simply return it. It will eventually
 556          * get propagated all the way to userspace, which should then try
 557          * again.
 558          */
 559         return rc;
 560 }
 561
 562 static int handle_pv_notification(struct kvm_vcpu *vcpu)
 563 {
 564         int ret;
 565
 566         if (vcpu->arch.sie_block->ipa == 0xb210)
 567                 return handle_pv_spx(vcpu);
 568         if (vcpu->arch.sie_block->ipa == 0xb220)
 569                 return handle_pv_sclp(vcpu);
 570         if (vcpu->arch.sie_block->ipa == 0xb9a4)
 571                 return handle_pv_uvc(vcpu);
 572         if (vcpu->arch.sie_block->ipa >> 8 == 0xae) {
 573                 /*
 574                  * Besides external call, other SIGP orders also cause a
 575                  * 108 (pv notify) intercept. In contrast to external call,
 576                  * these orders need to be emulated and hence the appropriate
 577                  * place to handle them is in handle_instruction().
 578                  * So first try kvm_s390_handle_sigp_pei() and if that isn't
 579                  * successful, go on with handle_instruction().
 580                  */
 581                 ret = kvm_s390_handle_sigp_pei(vcpu);
 582                 if (!ret)
 583                         return ret;
 584         }
 585
 586         return handle_instruction(vcpu);
 587 }
 588
 589 static bool should_handle_per_ifetch(const struct kvm_vcpu *vcpu, int rc)
 590 {
 591         /* Process PER, also if the instruction is processed in user space. */
 592         if (!(vcpu->arch.sie_block->icptstatus & 0x02))
 593                 return false;
 594         if (rc != 0 && rc != -EOPNOTSUPP)
 595                 return false;
 596         if (guestdbg_sstep_enabled(vcpu) && vcpu->arch.local_int.pending_irqs)
 597                 /* __vcpu_run() will exit after delivering the interrupt. */
 598                 return false;
 599         return true;
 600 }
 601
 602 int kvm_handle_sie_intercept(struct kvm_vcpu *vcpu)
 603 {
 604         int rc, per_rc = 0;
 605
 606         if (kvm_is_ucontrol(vcpu->kvm))
 607                 return -EOPNOTSUPP;
 608
 609         switch (vcpu->arch.sie_block->icptcode) {
 610         case ICPT_EXTREQ:
 611                 vcpu->stat.exit_external_request++;
 612                 return 0;
 613         case ICPT_IOREQ:
 614                 vcpu->stat.exit_io_request++;
 615                 return 0;
 616         case ICPT_INST:
 617                 rc = handle_instruction(vcpu);
 618                 break;
 619         case ICPT_PROGI:
 620                 return handle_prog(vcpu);
 621         case ICPT_EXTINT:
 622                 return handle_external_interrupt(vcpu);
 623         case ICPT_WAIT:
 624                 return kvm_s390_handle_wait(vcpu);
 625         case ICPT_VALIDITY:
 626                 return handle_validity(vcpu);
 627         case ICPT_STOP:
 628                 return handle_stop(vcpu);
 629         case ICPT_OPEREXC:
 630                 rc = handle_operexc(vcpu);
 631                 break;
 632         case ICPT_PARTEXEC:
 633                 rc = handle_partial_execution(vcpu);
 634                 break;
 635         case ICPT_KSS:
 636                 /* Instruction will be redriven, skip the PER check. */
 637                 return kvm_s390_skey_check_enable(vcpu);
 638         case ICPT_MCHKREQ:
 639         case ICPT_INT_ENABLE:
 640                 /*
 641                  * PSW bit 13 or a CR (0, 6, 14) changed and we might
 642                  * now be able to deliver interrupts. The pre-run code
 643                  * will take care of this.
 644                  */
 645                 rc = 0;
 646                 break;
 647         case ICPT_PV_INSTR:
 648                 rc = handle_instruction(vcpu);
 649                 break;
 650         case ICPT_PV_NOTIFY:
 651                 rc = handle_pv_notification(vcpu);
 652                 break;
 653         case ICPT_PV_PREF:
 654                 rc = 0;
 655                 gmap_convert_to_secure(vcpu->arch.gmap,
 656                                        kvm_s390_get_prefix(vcpu));
 657                 gmap_convert_to_secure(vcpu->arch.gmap,
 658                                        kvm_s390_get_prefix(vcpu) + PAGE_SIZE);
 659                 break;
 660         default:
 661                 return -EOPNOTSUPP;
 662         }
 663
 664         if (should_handle_per_ifetch(vcpu, rc))
 665                 per_rc = kvm_s390_handle_per_ifetch_icpt(vcpu);
 666         return per_rc ? per_rc : rc;
 667 }