arch/s390/kvm/interrupt.c - kernel/msm-4.19 - Gitiles

 /*
  * interrupt.c - 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 <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_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_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 = 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_CPU_ADDRESS, 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++;
 		vcpu->arch.sie_block->prefix = inti->prefix.address;
 		vcpu->arch.sie_block->ihcpu = 0xffff;
 		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;
 		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_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_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;
 }
	/*
	* interrupt.c - 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 <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_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_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 = 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_CPU_ADDRESS, 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++;
	vcpu->arch.sie_block->prefix = inti->prefix.address;
	vcpu->arch.sie_block->ihcpu = 0xffff;
	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;
	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_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_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;
	}