arch/s390/kvm/interrupt.c

   1 /*
   2  * interrupt.c - handling kvm guest interrupts
   3  *
   4  * Copyright IBM Corp. 2008
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License (version 2 only)
   8  * as published by the Free Software Foundation.
   9  *
  10  *    Author(s): Carsten Otte <cotte@de.ibm.com>
  11  */
  12
  13 #include <asm/lowcore.h>
  14 #include <asm/uaccess.h>
  15 #include <linux/hrtimer.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/kvm_host.h>
  18 #include <linux/signal.h>
  19 #include "kvm-s390.h"
  20 #include "gaccess.h"
  21
  22 static int psw_extint_disabled(struct kvm_vcpu *vcpu)
  23 {
  24         return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT);
  25 }
  26
  27 static int psw_interrupts_disabled(struct kvm_vcpu *vcpu)
  28 {
  29         if ((vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PER) ||
  30             (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_IO) ||
  31             (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT))
  32                 return 0;
  33         return 1;
  34 }
  35
  36 static int __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
  37                                       struct kvm_s390_interrupt_info *inti)
  38 {
  39         switch (inti->type) {
  40         case KVM_S390_INT_EMERGENCY:
  41                 if (psw_extint_disabled(vcpu))
  42                         return 0;
  43                 if (vcpu->arch.sie_block->gcr[0] & 0x4000ul)
  44                         return 1;
  45                 return 0;
  46         case KVM_S390_INT_SERVICE:
  47                 if (psw_extint_disabled(vcpu))
  48                         return 0;
  49                 if (vcpu->arch.sie_block->gcr[0] & 0x200ul)
  50                         return 1;
  51                 return 0;
  52         case KVM_S390_INT_VIRTIO:
  53                 if (psw_extint_disabled(vcpu))
  54                         return 0;
  55                 if (vcpu->arch.sie_block->gcr[0] & 0x200ul)
  56                         return 1;
  57                 return 0;
  58         case KVM_S390_PROGRAM_INT:
  59         case KVM_S390_SIGP_STOP:
  60         case KVM_S390_SIGP_SET_PREFIX:
  61         case KVM_S390_RESTART:
  62                 return 1;
  63         default:
  64                 BUG();
  65         }
  66         return 0;
  67 }
  68
  69 static void __set_cpu_idle(struct kvm_vcpu *vcpu)
  70 {
  71         BUG_ON(vcpu->vcpu_id > KVM_MAX_VCPUS - 1);
  72         atomic_set_mask(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
  73         set_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask);
  74 }
  75
  76 static void __unset_cpu_idle(struct kvm_vcpu *vcpu)
  77 {
  78         BUG_ON(vcpu->vcpu_id > KVM_MAX_VCPUS - 1);
  79         atomic_clear_mask(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
  80         clear_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask);
  81 }
  82
  83 static void __reset_intercept_indicators(struct kvm_vcpu *vcpu)
  84 {
  85         atomic_clear_mask(CPUSTAT_ECALL_PEND |
  86                 CPUSTAT_IO_INT | CPUSTAT_EXT_INT | CPUSTAT_STOP_INT,
  87                 &vcpu->arch.sie_block->cpuflags);
  88         vcpu->arch.sie_block->lctl = 0x0000;
  89 }
  90
  91 static void __set_cpuflag(struct kvm_vcpu *vcpu, u32 flag)
  92 {
  93         atomic_set_mask(flag, &vcpu->arch.sie_block->cpuflags);
  94 }
  95
  96 static void __set_intercept_indicator(struct kvm_vcpu *vcpu,
  97                                       struct kvm_s390_interrupt_info *inti)
  98 {
  99         switch (inti->type) {
 100         case KVM_S390_INT_EMERGENCY:
 101         case KVM_S390_INT_SERVICE:
 102         case KVM_S390_INT_VIRTIO:
 103                 if (psw_extint_disabled(vcpu))
 104                         __set_cpuflag(vcpu, CPUSTAT_EXT_INT);
 105                 else
 106                         vcpu->arch.sie_block->lctl |= LCTL_CR0;
 107                 break;
 108         case KVM_S390_SIGP_STOP:
 109                 __set_cpuflag(vcpu, CPUSTAT_STOP_INT);
 110                 break;
 111         default:
 112                 BUG();
 113         }
 114 }
 115
 116 static void __do_deliver_interrupt(struct kvm_vcpu *vcpu,
 117                                    struct kvm_s390_interrupt_info *inti)
 118 {
 119         const unsigned short table[] = { 2, 4, 4, 6 };
 120         int rc, exception = 0;
 121
 122         switch (inti->type) {
 123         case KVM_S390_INT_EMERGENCY:
 124                 VCPU_EVENT(vcpu, 4, "%s", "interrupt: sigp emerg");
 125                 vcpu->stat.deliver_emergency_signal++;
 126                 rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x1201);
 127                 if (rc == -EFAULT)
 128                         exception = 1;
 129
 130                 rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
 131                          &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
 132                 if (rc == -EFAULT)
 133                         exception = 1;
 134
 135                 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
 136                         __LC_EXT_NEW_PSW, sizeof(psw_t));
 137                 if (rc == -EFAULT)
 138                         exception = 1;
 139                 break;
 140
 141         case KVM_S390_INT_SERVICE:
 142                 VCPU_EVENT(vcpu, 4, "interrupt: sclp parm:%x",
 143                            inti->ext.ext_params);
 144                 vcpu->stat.deliver_service_signal++;
 145                 rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x2401);
 146                 if (rc == -EFAULT)
 147                         exception = 1;
 148
 149                 rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
 150                          &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
 151                 if (rc == -EFAULT)
 152                         exception = 1;
 153
 154                 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
 155                         __LC_EXT_NEW_PSW, sizeof(psw_t));
 156                 if (rc == -EFAULT)
 157                         exception = 1;
 158
 159                 rc = put_guest_u32(vcpu, __LC_EXT_PARAMS, inti->ext.ext_params);
 160                 if (rc == -EFAULT)
 161                         exception = 1;
 162                 break;
 163
 164         case KVM_S390_INT_VIRTIO:
 165                 VCPU_EVENT(vcpu, 4, "interrupt: virtio parm:%x,parm64:%llx",
 166                            inti->ext.ext_params, inti->ext.ext_params2);
 167                 vcpu->stat.deliver_virtio_interrupt++;
 168                 rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x2603);
 169                 if (rc == -EFAULT)
 170                         exception = 1;
 171
 172                 rc = put_guest_u16(vcpu, __LC_CPU_ADDRESS, 0x0d00);
 173                 if (rc == -EFAULT)
 174                         exception = 1;
 175
 176                 rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
 177                          &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
 178                 if (rc == -EFAULT)
 179                         exception = 1;
 180
 181                 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
 182                         __LC_EXT_NEW_PSW, sizeof(psw_t));
 183                 if (rc == -EFAULT)
 184                         exception = 1;
 185
 186                 rc = put_guest_u32(vcpu, __LC_EXT_PARAMS, inti->ext.ext_params);
 187                 if (rc == -EFAULT)
 188                         exception = 1;
 189
 190                 rc = put_guest_u64(vcpu, __LC_PFAULT_INTPARM,
 191                         inti->ext.ext_params2);
 192                 if (rc == -EFAULT)
 193                         exception = 1;
 194                 break;
 195
 196         case KVM_S390_SIGP_STOP:
 197                 VCPU_EVENT(vcpu, 4, "%s", "interrupt: cpu stop");
 198                 vcpu->stat.deliver_stop_signal++;
 199                 __set_intercept_indicator(vcpu, inti);
 200                 break;
 201
 202         case KVM_S390_SIGP_SET_PREFIX:
 203                 VCPU_EVENT(vcpu, 4, "interrupt: set prefix to %x",
 204                            inti->prefix.address);
 205                 vcpu->stat.deliver_prefix_signal++;
 206                 vcpu->arch.sie_block->prefix = inti->prefix.address;
 207                 vcpu->arch.sie_block->ihcpu = 0xffff;
 208                 break;
 209
 210         case KVM_S390_RESTART:
 211                 VCPU_EVENT(vcpu, 4, "%s", "interrupt: cpu restart");
 212                 vcpu->stat.deliver_restart_signal++;
 213                 rc = copy_to_guest(vcpu, offsetof(struct _lowcore,
 214                   restart_old_psw), &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
 215                 if (rc == -EFAULT)
 216                         exception = 1;
 217
 218                 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
 219                         offsetof(struct _lowcore, restart_psw), sizeof(psw_t));
 220                 if (rc == -EFAULT)
 221                         exception = 1;
 222                 break;
 223
 224         case KVM_S390_PROGRAM_INT:
 225                 VCPU_EVENT(vcpu, 4, "interrupt: pgm check code:%x, ilc:%x",
 226                            inti->pgm.code,
 227                            table[vcpu->arch.sie_block->ipa >> 14]);
 228                 vcpu->stat.deliver_program_int++;
 229                 rc = put_guest_u16(vcpu, __LC_PGM_INT_CODE, inti->pgm.code);
 230                 if (rc == -EFAULT)
 231                         exception = 1;
 232
 233                 rc = put_guest_u16(vcpu, __LC_PGM_ILC,
 234                         table[vcpu->arch.sie_block->ipa >> 14]);
 235                 if (rc == -EFAULT)
 236                         exception = 1;
 237
 238                 rc = copy_to_guest(vcpu, __LC_PGM_OLD_PSW,
 239                          &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
 240                 if (rc == -EFAULT)
 241                         exception = 1;
 242
 243                 rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
 244                         __LC_PGM_NEW_PSW, sizeof(psw_t));
 245                 if (rc == -EFAULT)
 246                         exception = 1;
 247                 break;
 248
 249         default:
 250                 BUG();
 251         }
 252         if (exception) {
 253                 printk("kvm: The guest lowcore is not mapped during interrupt "
 254                         "delivery, killing userspace\n");
 255                 do_exit(SIGKILL);
 256         }
 257 }
 258
 259 static int __try_deliver_ckc_interrupt(struct kvm_vcpu *vcpu)
 260 {
 261         int rc, exception = 0;
 262
 263         if (psw_extint_disabled(vcpu))
 264                 return 0;
 265         if (!(vcpu->arch.sie_block->gcr[0] & 0x800ul))
 266                 return 0;
 267         rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x1004);
 268         if (rc == -EFAULT)
 269                 exception = 1;
 270         rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
 271                  &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
 272         if (rc == -EFAULT)
 273                 exception = 1;
 274         rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
 275                 __LC_EXT_NEW_PSW, sizeof(psw_t));
 276         if (rc == -EFAULT)
 277                 exception = 1;
 278         if (exception) {
 279                 printk("kvm: The guest lowcore is not mapped during interrupt "
 280                         "delivery, killing userspace\n");
 281                 do_exit(SIGKILL);
 282         }
 283         return 1;
 284 }
 285
 286 int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu)
 287 {
 288         struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 289         struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int;
 290         struct kvm_s390_interrupt_info  *inti;
 291         int rc = 0;
 292
 293         if (atomic_read(&li->active)) {
 294                 spin_lock_bh(&li->lock);
 295                 list_for_each_entry(inti, &li->list, list)
 296                         if (__interrupt_is_deliverable(vcpu, inti)) {
 297                                 rc = 1;
 298                                 break;
 299                         }
 300                 spin_unlock_bh(&li->lock);
 301         }
 302
 303         if ((!rc) && atomic_read(&fi->active)) {
 304                 spin_lock(&fi->lock);
 305                 list_for_each_entry(inti, &fi->list, list)
 306                         if (__interrupt_is_deliverable(vcpu, inti)) {
 307                                 rc = 1;
 308                                 break;
 309                         }
 310                 spin_unlock(&fi->lock);
 311         }
 312
 313         if ((!rc) && (vcpu->arch.sie_block->ckc <
 314                 get_clock() + vcpu->arch.sie_block->epoch)) {
 315                 if ((!psw_extint_disabled(vcpu)) &&
 316                         (vcpu->arch.sie_block->gcr[0] & 0x800ul))
 317                         rc = 1;
 318         }
 319
 320         return rc;
 321 }
 322
 323 int kvm_arch_interrupt_allowed(struct kvm_vcpu *vcpu)
 324 {
 325         /* do real check here */
 326         return 1;
 327 }
 328
 329 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
 330 {
 331         return 0;
 332 }
 333
 334 int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
 335 {
 336         u64 now, sltime;
 337         DECLARE_WAITQUEUE(wait, current);
 338
 339         vcpu->stat.exit_wait_state++;
 340         if (kvm_cpu_has_interrupt(vcpu))
 341                 return 0;
 342
 343         __set_cpu_idle(vcpu);
 344         spin_lock_bh(&vcpu->arch.local_int.lock);
 345         vcpu->arch.local_int.timer_due = 0;
 346         spin_unlock_bh(&vcpu->arch.local_int.lock);
 347
 348         if (psw_interrupts_disabled(vcpu)) {
 349                 VCPU_EVENT(vcpu, 3, "%s", "disabled wait");
 350                 __unset_cpu_idle(vcpu);
 351                 return -ENOTSUPP; /* disabled wait */
 352         }
 353
 354         if (psw_extint_disabled(vcpu) ||
 355             (!(vcpu->arch.sie_block->gcr[0] & 0x800ul))) {
 356                 VCPU_EVENT(vcpu, 3, "%s", "enabled wait w/o timer");
 357                 goto no_timer;
 358         }
 359
 360         now = get_clock() + vcpu->arch.sie_block->epoch;
 361         if (vcpu->arch.sie_block->ckc < now) {
 362                 __unset_cpu_idle(vcpu);
 363                 return 0;
 364         }
 365
 366         sltime = ((vcpu->arch.sie_block->ckc - now)*125)>>9;
 367
 368         hrtimer_start(&vcpu->arch.ckc_timer, ktime_set (0, sltime) , HRTIMER_MODE_REL);
 369         VCPU_EVENT(vcpu, 5, "enabled wait via clock comparator: %llx ns", sltime);
 370 no_timer:
 371         spin_lock(&vcpu->arch.local_int.float_int->lock);
 372         spin_lock_bh(&vcpu->arch.local_int.lock);
 373         add_wait_queue(&vcpu->arch.local_int.wq, &wait);
 374         while (list_empty(&vcpu->arch.local_int.list) &&
 375                 list_empty(&vcpu->arch.local_int.float_int->list) &&
 376                 (!vcpu->arch.local_int.timer_due) &&
 377                 !signal_pending(current)) {
 378                 set_current_state(TASK_INTERRUPTIBLE);
 379                 spin_unlock_bh(&vcpu->arch.local_int.lock);
 380                 spin_unlock(&vcpu->arch.local_int.float_int->lock);
 381                 vcpu_put(vcpu);
 382                 schedule();
 383                 vcpu_load(vcpu);
 384                 spin_lock(&vcpu->arch.local_int.float_int->lock);
 385                 spin_lock_bh(&vcpu->arch.local_int.lock);
 386         }
 387         __unset_cpu_idle(vcpu);
 388         __set_current_state(TASK_RUNNING);
 389         remove_wait_queue(&vcpu->arch.local_int.wq, &wait);
 390         spin_unlock_bh(&vcpu->arch.local_int.lock);
 391         spin_unlock(&vcpu->arch.local_int.float_int->lock);
 392         hrtimer_try_to_cancel(&vcpu->arch.ckc_timer);
 393         return 0;
 394 }
 395
 396 void kvm_s390_tasklet(unsigned long parm)
 397 {
 398         struct kvm_vcpu *vcpu = (struct kvm_vcpu *) parm;
 399
 400         spin_lock(&vcpu->arch.local_int.lock);
 401         vcpu->arch.local_int.timer_due = 1;
 402         if (waitqueue_active(&vcpu->arch.local_int.wq))
 403                 wake_up_interruptible(&vcpu->arch.local_int.wq);
 404         spin_unlock(&vcpu->arch.local_int.lock);
 405 }
 406
 407 /*
 408  * low level hrtimer wake routine. Because this runs in hardirq context
 409  * we schedule a tasklet to do the real work.
 410  */
 411 enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer)
 412 {
 413         struct kvm_vcpu *vcpu;
 414
 415         vcpu = container_of(timer, struct kvm_vcpu, arch.ckc_timer);
 416         tasklet_schedule(&vcpu->arch.tasklet);
 417
 418         return HRTIMER_NORESTART;
 419 }
 420
 421 void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
 422 {
 423         struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 424         struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int;
 425         struct kvm_s390_interrupt_info  *n, *inti = NULL;
 426         int deliver;
 427
 428         __reset_intercept_indicators(vcpu);
 429         if (atomic_read(&li->active)) {
 430                 do {
 431                         deliver = 0;
 432                         spin_lock_bh(&li->lock);
 433                         list_for_each_entry_safe(inti, n, &li->list, list) {
 434                                 if (__interrupt_is_deliverable(vcpu, inti)) {
 435                                         list_del(&inti->list);
 436                                         deliver = 1;
 437                                         break;
 438                                 }
 439                                 __set_intercept_indicator(vcpu, inti);
 440                         }
 441                         if (list_empty(&li->list))
 442                                 atomic_set(&li->active, 0);
 443                         spin_unlock_bh(&li->lock);
 444                         if (deliver) {
 445                                 __do_deliver_interrupt(vcpu, inti);
 446                                 kfree(inti);
 447                         }
 448                 } while (deliver);
 449         }
 450
 451         if ((vcpu->arch.sie_block->ckc <
 452                 get_clock() + vcpu->arch.sie_block->epoch))
 453                 __try_deliver_ckc_interrupt(vcpu);
 454
 455         if (atomic_read(&fi->active)) {
 456                 do {
 457                         deliver = 0;
 458                         spin_lock(&fi->lock);
 459                         list_for_each_entry_safe(inti, n, &fi->list, list) {
 460                                 if (__interrupt_is_deliverable(vcpu, inti)) {
 461                                         list_del(&inti->list);
 462                                         deliver = 1;
 463                                         break;
 464                                 }
 465                                 __set_intercept_indicator(vcpu, inti);
 466                         }
 467                         if (list_empty(&fi->list))
 468                                 atomic_set(&fi->active, 0);
 469                         spin_unlock(&fi->lock);
 470                         if (deliver) {
 471                                 __do_deliver_interrupt(vcpu, inti);
 472                                 kfree(inti);
 473                         }
 474                 } while (deliver);
 475         }
 476 }
 477
 478 int kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code)
 479 {
 480         struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 481         struct kvm_s390_interrupt_info *inti;
 482
 483         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 484         if (!inti)
 485                 return -ENOMEM;
 486
 487         inti->type = KVM_S390_PROGRAM_INT;;
 488         inti->pgm.code = code;
 489
 490         VCPU_EVENT(vcpu, 3, "inject: program check %d (from kernel)", code);
 491         spin_lock_bh(&li->lock);
 492         list_add(&inti->list, &li->list);
 493         atomic_set(&li->active, 1);
 494         BUG_ON(waitqueue_active(&li->wq));
 495         spin_unlock_bh(&li->lock);
 496         return 0;
 497 }
 498
 499 int kvm_s390_inject_vm(struct kvm *kvm,
 500                        struct kvm_s390_interrupt *s390int)
 501 {
 502         struct kvm_s390_local_interrupt *li;
 503         struct kvm_s390_float_interrupt *fi;
 504         struct kvm_s390_interrupt_info *inti;
 505         int sigcpu;
 506
 507         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 508         if (!inti)
 509                 return -ENOMEM;
 510
 511         switch (s390int->type) {
 512         case KVM_S390_INT_VIRTIO:
 513                 VM_EVENT(kvm, 5, "inject: virtio parm:%x,parm64:%llx",
 514                          s390int->parm, s390int->parm64);
 515                 inti->type = s390int->type;
 516                 inti->ext.ext_params = s390int->parm;
 517                 inti->ext.ext_params2 = s390int->parm64;
 518                 break;
 519         case KVM_S390_INT_SERVICE:
 520                 VM_EVENT(kvm, 5, "inject: sclp parm:%x", s390int->parm);
 521                 inti->type = s390int->type;
 522                 inti->ext.ext_params = s390int->parm;
 523                 break;
 524         case KVM_S390_PROGRAM_INT:
 525         case KVM_S390_SIGP_STOP:
 526         case KVM_S390_INT_EMERGENCY:
 527         default:
 528                 kfree(inti);
 529                 return -EINVAL;
 530         }
 531
 532         mutex_lock(&kvm->lock);
 533         fi = &kvm->arch.float_int;
 534         spin_lock(&fi->lock);
 535         list_add_tail(&inti->list, &fi->list);
 536         atomic_set(&fi->active, 1);
 537         sigcpu = find_first_bit(fi->idle_mask, KVM_MAX_VCPUS);
 538         if (sigcpu == KVM_MAX_VCPUS) {
 539                 do {
 540                         sigcpu = fi->next_rr_cpu++;
 541                         if (sigcpu == KVM_MAX_VCPUS)
 542                                 sigcpu = fi->next_rr_cpu = 0;
 543                 } while (fi->local_int[sigcpu] == NULL);
 544         }
 545         li = fi->local_int[sigcpu];
 546         spin_lock_bh(&li->lock);
 547         atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
 548         if (waitqueue_active(&li->wq))
 549                 wake_up_interruptible(&li->wq);
 550         spin_unlock_bh(&li->lock);
 551         spin_unlock(&fi->lock);
 552         mutex_unlock(&kvm->lock);
 553         return 0;
 554 }
 555
 556 int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
 557                          struct kvm_s390_interrupt *s390int)
 558 {
 559         struct kvm_s390_local_interrupt *li;
 560         struct kvm_s390_interrupt_info *inti;
 561
 562         inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 563         if (!inti)
 564                 return -ENOMEM;
 565
 566         switch (s390int->type) {
 567         case KVM_S390_PROGRAM_INT:
 568                 if (s390int->parm & 0xffff0000) {
 569                         kfree(inti);
 570                         return -EINVAL;
 571                 }
 572                 inti->type = s390int->type;
 573                 inti->pgm.code = s390int->parm;
 574                 VCPU_EVENT(vcpu, 3, "inject: program check %d (from user)",
 575                            s390int->parm);
 576                 break;
 577         case KVM_S390_SIGP_SET_PREFIX:
 578                 inti->prefix.address = s390int->parm;
 579                 inti->type = s390int->type;
 580                 VCPU_EVENT(vcpu, 3, "inject: set prefix to %x (from user)",
 581                            s390int->parm);
 582                 break;
 583         case KVM_S390_SIGP_STOP:
 584         case KVM_S390_RESTART:
 585         case KVM_S390_INT_EMERGENCY:
 586                 VCPU_EVENT(vcpu, 3, "inject: type %x", s390int->type);
 587                 inti->type = s390int->type;
 588                 break;
 589         case KVM_S390_INT_VIRTIO:
 590         case KVM_S390_INT_SERVICE:
 591         default:
 592                 kfree(inti);
 593                 return -EINVAL;
 594         }
 595
 596         mutex_lock(&vcpu->kvm->lock);
 597         li = &vcpu->arch.local_int;
 598         spin_lock_bh(&li->lock);
 599         if (inti->type == KVM_S390_PROGRAM_INT)
 600                 list_add(&inti->list, &li->list);
 601         else
 602                 list_add_tail(&inti->list, &li->list);
 603         atomic_set(&li->active, 1);
 604         if (inti->type == KVM_S390_SIGP_STOP)
 605                 li->action_bits |= ACTION_STOP_ON_STOP;
 606         atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
 607         if (waitqueue_active(&li->wq))
 608                 wake_up_interruptible(&vcpu->arch.local_int.wq);
 609         spin_unlock_bh(&li->lock);
 610         mutex_unlock(&vcpu->kvm->lock);
 611         return 0;
 612 }