text: /*
   * handling kvm guest interrupts
   *
   * Copyright IBM Corp. 2008
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License (version 2 only)
   * as published by the Free Software Foundation.
   *
   *    Author(s): Carsten Otte <cotte@de.ibm.com>
   */
  
  #include <linux/interrupt.h>
  #include <linux/kvm_host.h>
  #include <linux/hrtimer.h>
  #include <linux/signal.h>
  #include <linux/slab.h>
  #include <asm/asm-offsets.h>
  #include <asm/uaccess.h>
  #include "kvm-s390.h"
  #include "gaccess.h"
  
  static int psw_extint_disabled(struct kvm_vcpu *vcpu)
  {
  	return !(vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT);
  }
  
  static int psw_interrupts_disabled(struct kvm_vcpu *vcpu)
  {
  	if ((vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PER) ||
  	    (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_IO) ||
  	    (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_EXT))
  		return 0;
  	return 1;
  }
  
  static int __interrupt_is_deliverable(struct kvm_vcpu *vcpu,
  				      struct kvm_s390_interrupt_info *inti)
  {
  	switch (inti->type) {
  	case KVM_S390_INT_EXTERNAL_CALL:
  		if (psw_extint_disabled(vcpu))
  			return 0;
  		if (vcpu->arch.sie_block->gcr[0] & 0x2000ul)
  			return 1;
  	case KVM_S390_INT_EMERGENCY:
  		if (psw_extint_disabled(vcpu))
  			return 0;
  		if (vcpu->arch.sie_block->gcr[0] & 0x4000ul)
  			return 1;
  		return 0;
  	case KVM_S390_INT_SERVICE:
  		if (psw_extint_disabled(vcpu))
  			return 0;
  		if (vcpu->arch.sie_block->gcr[0] & 0x200ul)
  			return 1;
  		return 0;
  	case KVM_S390_INT_VIRTIO:
  		if (psw_extint_disabled(vcpu))
  			return 0;
  		if (vcpu->arch.sie_block->gcr[0] & 0x200ul)
  			return 1;
  		return 0;
  	case KVM_S390_PROGRAM_INT:
  	case KVM_S390_SIGP_STOP:
  	case KVM_S390_SIGP_SET_PREFIX:
  	case KVM_S390_RESTART:
  		return 1;
  	default:
  		BUG();
  	}
  	return 0;
  }
  
  static void __set_cpu_idle(struct kvm_vcpu *vcpu)
  {
  	BUG_ON(vcpu->vcpu_id > KVM_MAX_VCPUS - 1);
  	atomic_set_mask(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
  	set_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask);
  }
  
  static void __unset_cpu_idle(struct kvm_vcpu *vcpu)
  {
  	BUG_ON(vcpu->vcpu_id > KVM_MAX_VCPUS - 1);
  	atomic_clear_mask(CPUSTAT_WAIT, &vcpu->arch.sie_block->cpuflags);
  	clear_bit(vcpu->vcpu_id, vcpu->arch.local_int.float_int->idle_mask);
  }
  
  static void __reset_intercept_indicators(struct kvm_vcpu *vcpu)
  {
  	atomic_clear_mask(CPUSTAT_ECALL_PEND |
  		CPUSTAT_IO_INT | CPUSTAT_EXT_INT | CPUSTAT_STOP_INT,
  		&vcpu->arch.sie_block->cpuflags);
  	vcpu->arch.sie_block->lctl = 0x0000;
  }
  
  static void __set_cpuflag(struct kvm_vcpu *vcpu, u32 flag)
  {
  	atomic_set_mask(flag, &vcpu->arch.sie_block->cpuflags);
  }
  
  static void __set_intercept_indicator(struct kvm_vcpu *vcpu,
  				      struct kvm_s390_interrupt_info *inti)
  {
  	switch (inti->type) {
  	case KVM_S390_INT_EXTERNAL_CALL:
  	case KVM_S390_INT_EMERGENCY:
  	case KVM_S390_INT_SERVICE:
  	case KVM_S390_INT_VIRTIO:
  		if (psw_extint_disabled(vcpu))
  			__set_cpuflag(vcpu, CPUSTAT_EXT_INT);
  		else
  			vcpu->arch.sie_block->lctl |= LCTL_CR0;
  		break;
  	case KVM_S390_SIGP_STOP:
  		__set_cpuflag(vcpu, CPUSTAT_STOP_INT);
  		break;
  	default:
  		BUG();
  	}
  }
  
  static void __do_deliver_interrupt(struct kvm_vcpu *vcpu,
  				   struct kvm_s390_interrupt_info *inti)
  {
  	const unsigned short table[] = { 2, 4, 4, 6 };
  	int rc, exception = 0;
  
  	switch (inti->type) {
  	case KVM_S390_INT_EMERGENCY:
  		VCPU_EVENT(vcpu, 4, "%s", "interrupt: sigp emerg");
  		vcpu->stat.deliver_emergency_signal++;
  		rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x1201);
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = put_guest_u16(vcpu, __LC_EXT_CPU_ADDR, inti->emerg.code);
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
  			 &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
  			__LC_EXT_NEW_PSW, sizeof(psw_t));
  		if (rc == -EFAULT)
  			exception = 1;
  		break;
  
  	case KVM_S390_INT_EXTERNAL_CALL:
  		VCPU_EVENT(vcpu, 4, "%s", "interrupt: sigp ext call");
  		vcpu->stat.deliver_external_call++;
  		rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x1202);
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = put_guest_u16(vcpu, __LC_EXT_CPU_ADDR, inti->extcall.code);
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
  			 &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
  			__LC_EXT_NEW_PSW, sizeof(psw_t));
  		if (rc == -EFAULT)
  			exception = 1;
  		break;
  
  	case KVM_S390_INT_SERVICE:
  		VCPU_EVENT(vcpu, 4, "interrupt: sclp parm:%x",
  			   inti->ext.ext_params);
  		vcpu->stat.deliver_service_signal++;
  		rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x2401);
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
  			 &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
  			__LC_EXT_NEW_PSW, sizeof(psw_t));
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = put_guest_u32(vcpu, __LC_EXT_PARAMS, inti->ext.ext_params);
  		if (rc == -EFAULT)
  			exception = 1;
  		break;
  
  	case KVM_S390_INT_VIRTIO:
  		VCPU_EVENT(vcpu, 4, "interrupt: virtio parm:%x,parm64:%llx",
  			   inti->ext.ext_params, inti->ext.ext_params2);
  		vcpu->stat.deliver_virtio_interrupt++;
  		rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x2603);
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = put_guest_u16(vcpu, __LC_EXT_CPU_ADDR, 0x0d00);
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
  			 &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
  			__LC_EXT_NEW_PSW, sizeof(psw_t));
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = put_guest_u32(vcpu, __LC_EXT_PARAMS, inti->ext.ext_params);
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = put_guest_u64(vcpu, __LC_EXT_PARAMS2,
  				   inti->ext.ext_params2);
  		if (rc == -EFAULT)
  			exception = 1;
  		break;
  
  	case KVM_S390_SIGP_STOP:
  		VCPU_EVENT(vcpu, 4, "%s", "interrupt: cpu stop");
  		vcpu->stat.deliver_stop_signal++;
  		__set_intercept_indicator(vcpu, inti);
  		break;
  
  	case KVM_S390_SIGP_SET_PREFIX:
  		VCPU_EVENT(vcpu, 4, "interrupt: set prefix to %x",
  			   inti->prefix.address);
  		vcpu->stat.deliver_prefix_signal++;
  		kvm_s390_set_prefix(vcpu, inti->prefix.address);
  		break;
  
  	case KVM_S390_RESTART:
  		VCPU_EVENT(vcpu, 4, "%s", "interrupt: cpu restart");
  		vcpu->stat.deliver_restart_signal++;
  		rc = copy_to_guest(vcpu, offsetof(struct _lowcore,
  		  restart_old_psw), &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
  			offsetof(struct _lowcore, restart_psw), sizeof(psw_t));
  		if (rc == -EFAULT)
  			exception = 1;
  		atomic_clear_mask(CPUSTAT_STOPPED, &vcpu->arch.sie_block->cpuflags);
  		break;
  
  	case KVM_S390_PROGRAM_INT:
  		VCPU_EVENT(vcpu, 4, "interrupt: pgm check code:%x, ilc:%x",
  			   inti->pgm.code,
  			   table[vcpu->arch.sie_block->ipa >> 14]);
  		vcpu->stat.deliver_program_int++;
  		rc = put_guest_u16(vcpu, __LC_PGM_INT_CODE, inti->pgm.code);
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = put_guest_u16(vcpu, __LC_PGM_ILC,
  			table[vcpu->arch.sie_block->ipa >> 14]);
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = copy_to_guest(vcpu, __LC_PGM_OLD_PSW,
  			 &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
  		if (rc == -EFAULT)
  			exception = 1;
  
  		rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
  			__LC_PGM_NEW_PSW, sizeof(psw_t));
  		if (rc == -EFAULT)
  			exception = 1;
  		break;
  
  	default:
  		BUG();
  	}
  	if (exception) {
  		printk("kvm: The guest lowcore is not mapped during interrupt "
  			"delivery, killing userspace\n");
  		do_exit(SIGKILL);
  	}
  }
  
  static int __try_deliver_ckc_interrupt(struct kvm_vcpu *vcpu)
  {
  	int rc, exception = 0;
  
  	if (psw_extint_disabled(vcpu))
  		return 0;
  	if (!(vcpu->arch.sie_block->gcr[0] & 0x800ul))
  		return 0;
  	rc = put_guest_u16(vcpu, __LC_EXT_INT_CODE, 0x1004);
  	if (rc == -EFAULT)
  		exception = 1;
  	rc = copy_to_guest(vcpu, __LC_EXT_OLD_PSW,
  		 &vcpu->arch.sie_block->gpsw, sizeof(psw_t));
  	if (rc == -EFAULT)
  		exception = 1;
  	rc = copy_from_guest(vcpu, &vcpu->arch.sie_block->gpsw,
  		__LC_EXT_NEW_PSW, sizeof(psw_t));
  	if (rc == -EFAULT)
  		exception = 1;
  	if (exception) {
  		printk("kvm: The guest lowcore is not mapped during interrupt "
  			"delivery, killing userspace\n");
  		do_exit(SIGKILL);
  	}
  	return 1;
  }
  
  static int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu)
  {
  	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
  	struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int;
  	struct kvm_s390_interrupt_info  *inti;
  	int rc = 0;
  
  	if (atomic_read(&li->active)) {
  		spin_lock_bh(&li->lock);
  		list_for_each_entry(inti, &li->list, list)
  			if (__interrupt_is_deliverable(vcpu, inti)) {
  				rc = 1;
  				break;
  			}
  		spin_unlock_bh(&li->lock);
  	}
  
  	if ((!rc) && atomic_read(&fi->active)) {
  		spin_lock(&fi->lock);
  		list_for_each_entry(inti, &fi->list, list)
  			if (__interrupt_is_deliverable(vcpu, inti)) {
  				rc = 1;
  				break;
  			}
  		spin_unlock(&fi->lock);
  	}
  
  	if ((!rc) && (vcpu->arch.sie_block->ckc <
  		get_clock() + vcpu->arch.sie_block->epoch)) {
  		if ((!psw_extint_disabled(vcpu)) &&
  			(vcpu->arch.sie_block->gcr[0] & 0x800ul))
  			rc = 1;
  	}
  
  	return rc;
  }
  
  int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
  {
  	return 0;
  }
  
  int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
  {
  	u64 now, sltime;
  	DECLARE_WAITQUEUE(wait, current);
  
  	vcpu->stat.exit_wait_state++;
  	if (kvm_cpu_has_interrupt(vcpu))
  		return 0;
  
  	__set_cpu_idle(vcpu);
  	spin_lock_bh(&vcpu->arch.local_int.lock);
  	vcpu->arch.local_int.timer_due = 0;
  	spin_unlock_bh(&vcpu->arch.local_int.lock);
  
  	if (psw_interrupts_disabled(vcpu)) {
  		VCPU_EVENT(vcpu, 3, "%s", "disabled wait");
  		__unset_cpu_idle(vcpu);
  		return -EOPNOTSUPP; /* disabled wait */
  	}
  
  	if (psw_extint_disabled(vcpu) ||
  	    (!(vcpu->arch.sie_block->gcr[0] & 0x800ul))) {
  		VCPU_EVENT(vcpu, 3, "%s", "enabled wait w/o timer");
  		goto no_timer;
  	}
  
  	now = get_clock() + vcpu->arch.sie_block->epoch;
  	if (vcpu->arch.sie_block->ckc < now) {
  		__unset_cpu_idle(vcpu);
  		return 0;
  	}
  
  	sltime = ((vcpu->arch.sie_block->ckc - now)*125)>>9;
  
  	hrtimer_start(&vcpu->arch.ckc_timer, ktime_set (0, sltime) , HRTIMER_MODE_REL);
  	VCPU_EVENT(vcpu, 5, "enabled wait via clock comparator: %llx ns", sltime);
  no_timer:
  	spin_lock(&vcpu->arch.local_int.float_int->lock);
  	spin_lock_bh(&vcpu->arch.local_int.lock);
  	add_wait_queue(&vcpu->arch.local_int.wq, &wait);
  	while (list_empty(&vcpu->arch.local_int.list) &&
  		list_empty(&vcpu->arch.local_int.float_int->list) &&
  		(!vcpu->arch.local_int.timer_due) &&
  		!signal_pending(current)) {
  		set_current_state(TASK_INTERRUPTIBLE);
  		spin_unlock_bh(&vcpu->arch.local_int.lock);
  		spin_unlock(&vcpu->arch.local_int.float_int->lock);
  		vcpu_put(vcpu);
  		schedule();
  		vcpu_load(vcpu);
  		spin_lock(&vcpu->arch.local_int.float_int->lock);
  		spin_lock_bh(&vcpu->arch.local_int.lock);
  	}
  	__unset_cpu_idle(vcpu);
  	__set_current_state(TASK_RUNNING);
  	remove_wait_queue(&vcpu->arch.local_int.wq, &wait);
  	spin_unlock_bh(&vcpu->arch.local_int.lock);
  	spin_unlock(&vcpu->arch.local_int.float_int->lock);
  	hrtimer_try_to_cancel(&vcpu->arch.ckc_timer);
  	return 0;
  }
  
  void kvm_s390_tasklet(unsigned long parm)
  {
  	struct kvm_vcpu *vcpu = (struct kvm_vcpu *) parm;
  
  	spin_lock(&vcpu->arch.local_int.lock);
  	vcpu->arch.local_int.timer_due = 1;
  	if (waitqueue_active(&vcpu->arch.local_int.wq))
  		wake_up_interruptible(&vcpu->arch.local_int.wq);
  	spin_unlock(&vcpu->arch.local_int.lock);
  }
  
  /*
   * low level hrtimer wake routine. Because this runs in hardirq context
   * we schedule a tasklet to do the real work.
   */
  enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer)
  {
  	struct kvm_vcpu *vcpu;
  
  	vcpu = container_of(timer, struct kvm_vcpu, arch.ckc_timer);
  	tasklet_schedule(&vcpu->arch.tasklet);
  
  	return HRTIMER_NORESTART;
  }
  
  void kvm_s390_deliver_pending_interrupts(struct kvm_vcpu *vcpu)
  {
  	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
  	struct kvm_s390_float_interrupt *fi = vcpu->arch.local_int.float_int;
  	struct kvm_s390_interrupt_info  *n, *inti = NULL;
  	int deliver;
  
  	__reset_intercept_indicators(vcpu);
  	if (atomic_read(&li->active)) {
  		do {
  			deliver = 0;
  			spin_lock_bh(&li->lock);
  			list_for_each_entry_safe(inti, n, &li->list, list) {
  				if (__interrupt_is_deliverable(vcpu, inti)) {
  					list_del(&inti->list);
  					deliver = 1;
  					break;
  				}
  				__set_intercept_indicator(vcpu, inti);
  			}
  			if (list_empty(&li->list))
  				atomic_set(&li->active, 0);
  			spin_unlock_bh(&li->lock);
  			if (deliver) {
  				__do_deliver_interrupt(vcpu, inti);
  				kfree(inti);
  			}
  		} while (deliver);
  	}
  
  	if ((vcpu->arch.sie_block->ckc <
  		get_clock() + vcpu->arch.sie_block->epoch))
  		__try_deliver_ckc_interrupt(vcpu);
  
  	if (atomic_read(&fi->active)) {
  		do {
  			deliver = 0;
  			spin_lock(&fi->lock);
  			list_for_each_entry_safe(inti, n, &fi->list, list) {
  				if (__interrupt_is_deliverable(vcpu, inti)) {
  					list_del(&inti->list);
  					deliver = 1;
  					break;
  				}
  				__set_intercept_indicator(vcpu, inti);
  			}
  			if (list_empty(&fi->list))
  				atomic_set(&fi->active, 0);
  			spin_unlock(&fi->lock);
  			if (deliver) {
  				__do_deliver_interrupt(vcpu, inti);
  				kfree(inti);
  			}
  		} while (deliver);
  	}
  }
  
  int kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code)
  {
  	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
  	struct kvm_s390_interrupt_info *inti;
  
  	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
  	if (!inti)
  		return -ENOMEM;
  
  	inti->type = KVM_S390_PROGRAM_INT;
  	inti->pgm.code = code;
  
  	VCPU_EVENT(vcpu, 3, "inject: program check %d (from kernel)", code);
  	spin_lock_bh(&li->lock);
  	list_add(&inti->list, &li->list);
  	atomic_set(&li->active, 1);
  	BUG_ON(waitqueue_active(&li->wq));
  	spin_unlock_bh(&li->lock);
  	return 0;
  }
  
  int kvm_s390_inject_vm(struct kvm *kvm,
  		       struct kvm_s390_interrupt *s390int)
  {
  	struct kvm_s390_local_interrupt *li;
  	struct kvm_s390_float_interrupt *fi;
  	struct kvm_s390_interrupt_info *inti;
  	int sigcpu;
  
  	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
  	if (!inti)
  		return -ENOMEM;
  
  	switch (s390int->type) {
  	case KVM_S390_INT_VIRTIO:
  		VM_EVENT(kvm, 5, "inject: virtio parm:%x,parm64:%llx",
  			 s390int->parm, s390int->parm64);
  		inti->type = s390int->type;
  		inti->ext.ext_params = s390int->parm;
  		inti->ext.ext_params2 = s390int->parm64;
  		break;
  	case KVM_S390_INT_SERVICE:
  		VM_EVENT(kvm, 5, "inject: sclp parm:%x", s390int->parm);
  		inti->type = s390int->type;
  		inti->ext.ext_params = s390int->parm;
  		break;
  	case KVM_S390_PROGRAM_INT:
  	case KVM_S390_SIGP_STOP:
  	case KVM_S390_INT_EXTERNAL_CALL:
  	case KVM_S390_INT_EMERGENCY:
  	default:
  		kfree(inti);
  		return -EINVAL;
  	}
  
  	mutex_lock(&kvm->lock);
  	fi = &kvm->arch.float_int;
  	spin_lock(&fi->lock);
  	list_add_tail(&inti->list, &fi->list);
  	atomic_set(&fi->active, 1);
  	sigcpu = find_first_bit(fi->idle_mask, KVM_MAX_VCPUS);
  	if (sigcpu == KVM_MAX_VCPUS) {
  		do {
  			sigcpu = fi->next_rr_cpu++;
  			if (sigcpu == KVM_MAX_VCPUS)
  				sigcpu = fi->next_rr_cpu = 0;
  		} while (fi->local_int[sigcpu] == NULL);
  	}
  	li = fi->local_int[sigcpu];
  	spin_lock_bh(&li->lock);
  	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
  	if (waitqueue_active(&li->wq))
  		wake_up_interruptible(&li->wq);
  	spin_unlock_bh(&li->lock);
  	spin_unlock(&fi->lock);
  	mutex_unlock(&kvm->lock);
  	return 0;
  }
  
  int kvm_s390_inject_vcpu(struct kvm_vcpu *vcpu,
  			 struct kvm_s390_interrupt *s390int)
  {
  	struct kvm_s390_local_interrupt *li;
  	struct kvm_s390_interrupt_info *inti;
  
  	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
  	if (!inti)
  		return -ENOMEM;
  
  	switch (s390int->type) {
  	case KVM_S390_PROGRAM_INT:
  		if (s390int->parm & 0xffff0000) {
  			kfree(inti);
  			return -EINVAL;
  		}
  		inti->type = s390int->type;
  		inti->pgm.code = s390int->parm;
  		VCPU_EVENT(vcpu, 3, "inject: program check %d (from user)",
  			   s390int->parm);
  		break;
  	case KVM_S390_SIGP_SET_PREFIX:
  		inti->prefix.address = s390int->parm;
  		inti->type = s390int->type;
  		VCPU_EVENT(vcpu, 3, "inject: set prefix to %x (from user)",
  			   s390int->parm);
  		break;
  	case KVM_S390_SIGP_STOP:
  	case KVM_S390_RESTART:
  	case KVM_S390_INT_EXTERNAL_CALL:
  	case KVM_S390_INT_EMERGENCY:
  		VCPU_EVENT(vcpu, 3, "inject: type %x", s390int->type);
  		inti->type = s390int->type;
  		break;
  	case KVM_S390_INT_VIRTIO:
  	case KVM_S390_INT_SERVICE:
  	default:
  		kfree(inti);
  		return -EINVAL;
  	}
  
  	mutex_lock(&vcpu->kvm->lock);
  	li = &vcpu->arch.local_int;
  	spin_lock_bh(&li->lock);
  	if (inti->type == KVM_S390_PROGRAM_INT)
  		list_add(&inti->list, &li->list);
  	else
  		list_add_tail(&inti->list, &li->list);
  	atomic_set(&li->active, 1);
  	if (inti->type == KVM_S390_SIGP_STOP)
  		li->action_bits |= ACTION_STOP_ON_STOP;
  	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
  	if (waitqueue_active(&li->wq))
  		wake_up_interruptible(&vcpu->arch.local_int.wq);
  	spin_unlock_bh(&li->lock);
  	mutex_unlock(&vcpu->kvm->lock);
  	return 0;
  }
  