arch/s390/kvm/sigp.c - kernel/msm-4.9 - Gitiles

 /*
  * sigp.c - handlinge interprocessor communication
  *
  * Copyright IBM Corp. 2008,2009
  *
  * 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>
  *               Christian Borntraeger <borntraeger@de.ibm.com>
  *               Christian Ehrhardt <ehrhardt@de.ibm.com>
  */

 #include <linux/kvm.h>
 #include <linux/kvm_host.h>
 #include <linux/slab.h>
 #include "gaccess.h"
 #include "kvm-s390.h"

 /* sigp order codes */
 #define SIGP_SENSE             0x01
 #define SIGP_EXTERNAL_CALL     0x02
 #define SIGP_EMERGENCY         0x03
 #define SIGP_START             0x04
 #define SIGP_STOP              0x05
 #define SIGP_RESTART           0x06
 #define SIGP_STOP_STORE_STATUS 0x09
 #define SIGP_INITIAL_CPU_RESET 0x0b
 #define SIGP_CPU_RESET         0x0c
 #define SIGP_SET_PREFIX        0x0d
 #define SIGP_STORE_STATUS_ADDR 0x0e
 #define SIGP_SET_ARCH          0x12
 #define SIGP_SENSE_RUNNING     0x15

 /* cpu status bits */
 #define SIGP_STAT_EQUIPMENT_CHECK   0x80000000UL
 #define SIGP_STAT_NOT_RUNNING	    0x00000400UL
 #define SIGP_STAT_INCORRECT_STATE   0x00000200UL
 #define SIGP_STAT_INVALID_PARAMETER 0x00000100UL
 #define SIGP_STAT_EXT_CALL_PENDING  0x00000080UL
 #define SIGP_STAT_STOPPED           0x00000040UL
 #define SIGP_STAT_OPERATOR_INTERV   0x00000020UL
 #define SIGP_STAT_CHECK_STOP        0x00000010UL
 #define SIGP_STAT_INOPERATIVE       0x00000004UL
 #define SIGP_STAT_INVALID_ORDER     0x00000002UL
 #define SIGP_STAT_RECEIVER_CHECK    0x00000001UL


 static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
 			u64 *reg)
 {
 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 	int rc;

 	if (cpu_addr >= KVM_MAX_VCPUS)
 		return 3; /* not operational */

 	spin_lock(&fi->lock);
 	if (fi->local_int[cpu_addr] == NULL)
 		rc = 3; /* not operational */
 	else if (!(atomic_read(fi->local_int[cpu_addr]->cpuflags)
 		  & CPUSTAT_STOPPED)) {
 		*reg &= 0xffffffff00000000UL;
 		rc = 1; /* status stored */
 	} else {
 		*reg &= 0xffffffff00000000UL;
 		*reg |= SIGP_STAT_STOPPED;
 		rc = 1; /* status stored */
 	}
 	spin_unlock(&fi->lock);

 	VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", cpu_addr, rc);
 	return rc;
 }

 static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
 {
 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 	struct kvm_s390_local_interrupt *li;
 	struct kvm_s390_interrupt_info *inti;
 	int rc;

 	if (cpu_addr >= KVM_MAX_VCPUS)
 		return 3; /* not operational */

 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 	if (!inti)
 		return -ENOMEM;

 	inti->type = KVM_S390_INT_EMERGENCY;
 	inti->emerg.code = vcpu->vcpu_id;

 	spin_lock(&fi->lock);
 	li = fi->local_int[cpu_addr];
 	if (li == NULL) {
 		rc = 3; /* not operational */
 		kfree(inti);
 		goto unlock;
 	}
 	spin_lock_bh(&li->lock);
 	list_add_tail(&inti->list, &li->list);
 	atomic_set(&li->active, 1);
 	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
 	if (waitqueue_active(&li->wq))
 		wake_up_interruptible(&li->wq);
 	spin_unlock_bh(&li->lock);
 	rc = 0; /* order accepted */
 	VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
 unlock:
 	spin_unlock(&fi->lock);
 	return rc;
 }

 static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr)
 {
 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 	struct kvm_s390_local_interrupt *li;
 	struct kvm_s390_interrupt_info *inti;
 	int rc;

 	if (cpu_addr >= KVM_MAX_VCPUS)
 		return 3; /* not operational */

 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 	if (!inti)
 		return -ENOMEM;

 	inti->type = KVM_S390_INT_EXTERNAL_CALL;
 	inti->extcall.code = vcpu->vcpu_id;

 	spin_lock(&fi->lock);
 	li = fi->local_int[cpu_addr];
 	if (li == NULL) {
 		rc = 3; /* not operational */
 		kfree(inti);
 		goto unlock;
 	}
 	spin_lock_bh(&li->lock);
 	list_add_tail(&inti->list, &li->list);
 	atomic_set(&li->active, 1);
 	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
 	if (waitqueue_active(&li->wq))
 		wake_up_interruptible(&li->wq);
 	spin_unlock_bh(&li->lock);
 	rc = 0; /* order accepted */
 	VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x", cpu_addr);
 unlock:
 	spin_unlock(&fi->lock);
 	return rc;
 }

 static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
 {
 	struct kvm_s390_interrupt_info *inti;

 	inti = kzalloc(sizeof(*inti), GFP_ATOMIC);
 	if (!inti)
 		return -ENOMEM;
 	inti->type = KVM_S390_SIGP_STOP;

 	spin_lock_bh(&li->lock);
 	if ((atomic_read(li->cpuflags) & CPUSTAT_STOPPED))
 		goto out;
 	list_add_tail(&inti->list, &li->list);
 	atomic_set(&li->active, 1);
 	atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
 	li->action_bits |= action;
 	if (waitqueue_active(&li->wq))
 		wake_up_interruptible(&li->wq);
 out:
 	spin_unlock_bh(&li->lock);

 	return 0; /* order accepted */
 }

 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
 {
 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 	struct kvm_s390_local_interrupt *li;
 	int rc;

 	if (cpu_addr >= KVM_MAX_VCPUS)
 		return 3; /* not operational */

 	spin_lock(&fi->lock);
 	li = fi->local_int[cpu_addr];
 	if (li == NULL) {
 		rc = 3; /* not operational */
 		goto unlock;
 	}

 	rc = __inject_sigp_stop(li, action);

 unlock:
 	spin_unlock(&fi->lock);
 	VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
 	return rc;
 }

 int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
 {
 	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
 	return __inject_sigp_stop(li, action);
 }

 static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
 {
 	int rc;

 	switch (parameter & 0xff) {
 	case 0:
 		rc = 3; /* not operational */
 		break;
 	case 1:
 	case 2:
 		rc = 0; /* order accepted */
 		break;
 	default:
 		rc = -EOPNOTSUPP;
 	}
 	return rc;
 }

 static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
 			     u64 *reg)
 {
 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 	struct kvm_s390_local_interrupt *li = NULL;
 	struct kvm_s390_interrupt_info *inti;
 	int rc;
 	u8 tmp;

 	/* make sure that the new value is valid memory */
 	address = address & 0x7fffe000u;
 	if (copy_from_guest_absolute(vcpu, &tmp, address, 1) ||
 	   copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1)) {
 		*reg |= SIGP_STAT_INVALID_PARAMETER;
 		return 1; /* invalid parameter */
 	}

 	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
 	if (!inti)
 		return 2; /* busy */

 	spin_lock(&fi->lock);
 	if (cpu_addr < KVM_MAX_VCPUS)
 		li = fi->local_int[cpu_addr];

 	if (li == NULL) {
 		rc = 1; /* incorrect state */
 		*reg &= SIGP_STAT_INCORRECT_STATE;
 		kfree(inti);
 		goto out_fi;
 	}

 	spin_lock_bh(&li->lock);
 	/* cpu must be in stopped state */
 	if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
 		rc = 1; /* incorrect state */
 		*reg &= SIGP_STAT_INCORRECT_STATE;
 		kfree(inti);
 		goto out_li;
 	}

 	inti->type = KVM_S390_SIGP_SET_PREFIX;
 	inti->prefix.address = address;

 	list_add_tail(&inti->list, &li->list);
 	atomic_set(&li->active, 1);
 	if (waitqueue_active(&li->wq))
 		wake_up_interruptible(&li->wq);
 	rc = 0; /* order accepted */

 	VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
 out_li:
 	spin_unlock_bh(&li->lock);
 out_fi:
 	spin_unlock(&fi->lock);
 	return rc;
 }

 static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
 				u64 *reg)
 {
 	int rc;
 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;

 	if (cpu_addr >= KVM_MAX_VCPUS)
 		return 3; /* not operational */

 	spin_lock(&fi->lock);
 	if (fi->local_int[cpu_addr] == NULL)
 		rc = 3; /* not operational */
 	else {
 		if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
 		    & CPUSTAT_RUNNING) {
 			/* running */
 			rc = 1;
 		} else {
 			/* not running */
 			*reg &= 0xffffffff00000000UL;
 			*reg |= SIGP_STAT_NOT_RUNNING;
 			rc = 0;
 		}
 	}
 	spin_unlock(&fi->lock);

 	VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x", cpu_addr,
 		   rc);

 	return rc;
 }

 static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr)
 {
 	int rc = 0;
 	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
 	struct kvm_s390_local_interrupt *li;

 	if (cpu_addr >= KVM_MAX_VCPUS)
 		return 3; /* not operational */

 	spin_lock(&fi->lock);
 	li = fi->local_int[cpu_addr];
 	if (li == NULL) {
 		rc = 3; /* not operational */
 		goto out;
 	}

 	spin_lock_bh(&li->lock);
 	if (li->action_bits & ACTION_STOP_ON_STOP)
 		rc = 2; /* busy */
 	else
 		VCPU_EVENT(vcpu, 4, "sigp restart %x to handle userspace",
 			cpu_addr);
 	spin_unlock_bh(&li->lock);
 out:
 	spin_unlock(&fi->lock);
 	return rc;
 }

 int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 {
 	int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
 	int r3 = vcpu->arch.sie_block->ipa & 0x000f;
 	int base2 = vcpu->arch.sie_block->ipb >> 28;
 	int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
 	u32 parameter;
 	u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
 	u8 order_code;
 	int rc;

 	/* sigp in userspace can exit */
 	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
 		return kvm_s390_inject_program_int(vcpu,
 						   PGM_PRIVILEGED_OPERATION);

 	order_code = disp2;
 	if (base2)
 		order_code += vcpu->run->s.regs.gprs[base2];

 	if (r1 % 2)
 		parameter = vcpu->run->s.regs.gprs[r1];
 	else
 		parameter = vcpu->run->s.regs.gprs[r1 + 1];

 	switch (order_code) {
 	case SIGP_SENSE:
 		vcpu->stat.instruction_sigp_sense++;
 		rc = __sigp_sense(vcpu, cpu_addr,
 				  &vcpu->run->s.regs.gprs[r1]);
 		break;
 	case SIGP_EXTERNAL_CALL:
 		vcpu->stat.instruction_sigp_external_call++;
 		rc = __sigp_external_call(vcpu, cpu_addr);
 		break;
 	case SIGP_EMERGENCY:
 		vcpu->stat.instruction_sigp_emergency++;
 		rc = __sigp_emergency(vcpu, cpu_addr);
 		break;
 	case SIGP_STOP:
 		vcpu->stat.instruction_sigp_stop++;
 		rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
 		break;
 	case SIGP_STOP_STORE_STATUS:
 		vcpu->stat.instruction_sigp_stop++;
 		rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP |
 						 ACTION_STOP_ON_STOP);
 		break;
 	case SIGP_SET_ARCH:
 		vcpu->stat.instruction_sigp_arch++;
 		rc = __sigp_set_arch(vcpu, parameter);
 		break;
 	case SIGP_SET_PREFIX:
 		vcpu->stat.instruction_sigp_prefix++;
 		rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
 				       &vcpu->run->s.regs.gprs[r1]);
 		break;
 	case SIGP_SENSE_RUNNING:
 		vcpu->stat.instruction_sigp_sense_running++;
 		rc = __sigp_sense_running(vcpu, cpu_addr,
 					  &vcpu->run->s.regs.gprs[r1]);
 		break;
 	case SIGP_RESTART:
 		vcpu->stat.instruction_sigp_restart++;
 		rc = __sigp_restart(vcpu, cpu_addr);
 		if (rc == 2) /* busy */
 			break;
 		/* user space must know about restart */
 	default:
 		return -EOPNOTSUPP;
 	}

 	if (rc < 0)
 		return rc;

 	vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
 	vcpu->arch.sie_block->gpsw.mask |= (rc & 3ul) << 44;
 	return 0;
 }
	/*
	* sigp.c - handlinge interprocessor communication
	*
	* Copyright IBM Corp. 2008,2009
	*
	* 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>
	* Christian Borntraeger <borntraeger@de.ibm.com>
	* Christian Ehrhardt <ehrhardt@de.ibm.com>
	*/

	#include <linux/kvm.h>
	#include <linux/kvm_host.h>
	#include <linux/slab.h>
	#include "gaccess.h"
	#include "kvm-s390.h"

	/* sigp order codes */
	#define SIGP_SENSE 0x01
	#define SIGP_EXTERNAL_CALL 0x02
	#define SIGP_EMERGENCY 0x03
	#define SIGP_START 0x04
	#define SIGP_STOP 0x05
	#define SIGP_RESTART 0x06
	#define SIGP_STOP_STORE_STATUS 0x09
	#define SIGP_INITIAL_CPU_RESET 0x0b
	#define SIGP_CPU_RESET 0x0c
	#define SIGP_SET_PREFIX 0x0d
	#define SIGP_STORE_STATUS_ADDR 0x0e
	#define SIGP_SET_ARCH 0x12
	#define SIGP_SENSE_RUNNING 0x15

	/* cpu status bits */
	#define SIGP_STAT_EQUIPMENT_CHECK 0x80000000UL
	#define SIGP_STAT_NOT_RUNNING 0x00000400UL
	#define SIGP_STAT_INCORRECT_STATE 0x00000200UL
	#define SIGP_STAT_INVALID_PARAMETER 0x00000100UL
	#define SIGP_STAT_EXT_CALL_PENDING 0x00000080UL
	#define SIGP_STAT_STOPPED 0x00000040UL
	#define SIGP_STAT_OPERATOR_INTERV 0x00000020UL
	#define SIGP_STAT_CHECK_STOP 0x00000010UL
	#define SIGP_STAT_INOPERATIVE 0x00000004UL
	#define SIGP_STAT_INVALID_ORDER 0x00000002UL
	#define SIGP_STAT_RECEIVER_CHECK 0x00000001UL


	static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
	u64 *reg)
	{
	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
	int rc;

	if (cpu_addr >= KVM_MAX_VCPUS)
	return 3; /* not operational */

	spin_lock(&fi->lock);
	if (fi->local_int[cpu_addr] == NULL)
	rc = 3; /* not operational */
	else if (!(atomic_read(fi->local_int[cpu_addr]->cpuflags)
	& CPUSTAT_STOPPED)) {
	*reg &= 0xffffffff00000000UL;
	rc = 1; /* status stored */
	} else {
	*reg &= 0xffffffff00000000UL;
	*reg \|= SIGP_STAT_STOPPED;
	rc = 1; /* status stored */
	}
	spin_unlock(&fi->lock);

	VCPU_EVENT(vcpu, 4, "sensed status of cpu %x rc %x", cpu_addr, rc);
	return rc;
	}

	static int __sigp_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr)
	{
	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
	struct kvm_s390_local_interrupt *li;
	struct kvm_s390_interrupt_info *inti;
	int rc;

	if (cpu_addr >= KVM_MAX_VCPUS)
	return 3; /* not operational */

	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
	if (!inti)
	return -ENOMEM;

	inti->type = KVM_S390_INT_EMERGENCY;
	inti->emerg.code = vcpu->vcpu_id;

	spin_lock(&fi->lock);
	li = fi->local_int[cpu_addr];
	if (li == NULL) {
	rc = 3; /* not operational */
	kfree(inti);
	goto unlock;
	}
	spin_lock_bh(&li->lock);
	list_add_tail(&inti->list, &li->list);
	atomic_set(&li->active, 1);
	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
	if (waitqueue_active(&li->wq))
	wake_up_interruptible(&li->wq);
	spin_unlock_bh(&li->lock);
	rc = 0; /* order accepted */
	VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);
	unlock:
	spin_unlock(&fi->lock);
	return rc;
	}

	static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr)
	{
	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
	struct kvm_s390_local_interrupt *li;
	struct kvm_s390_interrupt_info *inti;
	int rc;

	if (cpu_addr >= KVM_MAX_VCPUS)
	return 3; /* not operational */

	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
	if (!inti)
	return -ENOMEM;

	inti->type = KVM_S390_INT_EXTERNAL_CALL;
	inti->extcall.code = vcpu->vcpu_id;

	spin_lock(&fi->lock);
	li = fi->local_int[cpu_addr];
	if (li == NULL) {
	rc = 3; /* not operational */
	kfree(inti);
	goto unlock;
	}
	spin_lock_bh(&li->lock);
	list_add_tail(&inti->list, &li->list);
	atomic_set(&li->active, 1);
	atomic_set_mask(CPUSTAT_EXT_INT, li->cpuflags);
	if (waitqueue_active(&li->wq))
	wake_up_interruptible(&li->wq);
	spin_unlock_bh(&li->lock);
	rc = 0; /* order accepted */
	VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x", cpu_addr);
	unlock:
	spin_unlock(&fi->lock);
	return rc;
	}

	static int __inject_sigp_stop(struct kvm_s390_local_interrupt *li, int action)
	{
	struct kvm_s390_interrupt_info *inti;

	inti = kzalloc(sizeof(*inti), GFP_ATOMIC);
	if (!inti)
	return -ENOMEM;
	inti->type = KVM_S390_SIGP_STOP;

	spin_lock_bh(&li->lock);
	if ((atomic_read(li->cpuflags) & CPUSTAT_STOPPED))
	goto out;
	list_add_tail(&inti->list, &li->list);
	atomic_set(&li->active, 1);
	atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
	li->action_bits \|= action;
	if (waitqueue_active(&li->wq))
	wake_up_interruptible(&li->wq);
	out:
	spin_unlock_bh(&li->lock);

	return 0; /* order accepted */
	}

	static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
	{
	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
	struct kvm_s390_local_interrupt *li;
	int rc;

	if (cpu_addr >= KVM_MAX_VCPUS)
	return 3; /* not operational */

	spin_lock(&fi->lock);
	li = fi->local_int[cpu_addr];
	if (li == NULL) {
	rc = 3; /* not operational */
	goto unlock;
	}

	rc = __inject_sigp_stop(li, action);

	unlock:
	spin_unlock(&fi->lock);
	VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);
	return rc;
	}

	int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action)
	{
	struct kvm_s390_local_interrupt *li = &vcpu->arch.local_int;
	return __inject_sigp_stop(li, action);
	}

	static int __sigp_set_arch(struct kvm_vcpu *vcpu, u32 parameter)
	{
	int rc;

	switch (parameter & 0xff) {
	case 0:
	rc = 3; /* not operational */
	break;
	case 1:
	case 2:
	rc = 0; /* order accepted */
	break;
	default:
	rc = -EOPNOTSUPP;
	}
	return rc;
	}

	static int __sigp_set_prefix(struct kvm_vcpu *vcpu, u16 cpu_addr, u32 address,
	u64 *reg)
	{
	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
	struct kvm_s390_local_interrupt *li = NULL;
	struct kvm_s390_interrupt_info *inti;
	int rc;
	u8 tmp;

	/* make sure that the new value is valid memory */
	address = address & 0x7fffe000u;
	if (copy_from_guest_absolute(vcpu, &tmp, address, 1) \|\|
	copy_from_guest_absolute(vcpu, &tmp, address + PAGE_SIZE, 1)) {
	*reg \|= SIGP_STAT_INVALID_PARAMETER;
	return 1; /* invalid parameter */
	}

	inti = kzalloc(sizeof(*inti), GFP_KERNEL);
	if (!inti)
	return 2; /* busy */

	spin_lock(&fi->lock);
	if (cpu_addr < KVM_MAX_VCPUS)
	li = fi->local_int[cpu_addr];

	if (li == NULL) {
	rc = 1; /* incorrect state */
	*reg &= SIGP_STAT_INCORRECT_STATE;
	kfree(inti);
	goto out_fi;
	}

	spin_lock_bh(&li->lock);
	/* cpu must be in stopped state */
	if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
	rc = 1; /* incorrect state */
	*reg &= SIGP_STAT_INCORRECT_STATE;
	kfree(inti);
	goto out_li;
	}

	inti->type = KVM_S390_SIGP_SET_PREFIX;
	inti->prefix.address = address;

	list_add_tail(&inti->list, &li->list);
	atomic_set(&li->active, 1);
	if (waitqueue_active(&li->wq))
	wake_up_interruptible(&li->wq);
	rc = 0; /* order accepted */

	VCPU_EVENT(vcpu, 4, "set prefix of cpu %02x to %x", cpu_addr, address);
	out_li:
	spin_unlock_bh(&li->lock);
	out_fi:
	spin_unlock(&fi->lock);
	return rc;
	}

	static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
	u64 *reg)
	{
	int rc;
	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;

	if (cpu_addr >= KVM_MAX_VCPUS)
	return 3; /* not operational */

	spin_lock(&fi->lock);
	if (fi->local_int[cpu_addr] == NULL)
	rc = 3; /* not operational */
	else {
	if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
	& CPUSTAT_RUNNING) {
	/* running */
	rc = 1;
	} else {
	/* not running */
	*reg &= 0xffffffff00000000UL;
	*reg \|= SIGP_STAT_NOT_RUNNING;
	rc = 0;
	}
	}
	spin_unlock(&fi->lock);

	VCPU_EVENT(vcpu, 4, "sensed running status of cpu %x rc %x", cpu_addr,
	rc);

	return rc;
	}

	static int __sigp_restart(struct kvm_vcpu *vcpu, u16 cpu_addr)
	{
	int rc = 0;
	struct kvm_s390_float_interrupt *fi = &vcpu->kvm->arch.float_int;
	struct kvm_s390_local_interrupt *li;

	if (cpu_addr >= KVM_MAX_VCPUS)
	return 3; /* not operational */

	spin_lock(&fi->lock);
	li = fi->local_int[cpu_addr];
	if (li == NULL) {
	rc = 3; /* not operational */
	goto out;
	}

	spin_lock_bh(&li->lock);
	if (li->action_bits & ACTION_STOP_ON_STOP)
	rc = 2; /* busy */
	else
	VCPU_EVENT(vcpu, 4, "sigp restart %x to handle userspace",
	cpu_addr);
	spin_unlock_bh(&li->lock);
	out:
	spin_unlock(&fi->lock);
	return rc;
	}

	int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
	{
	int r1 = (vcpu->arch.sie_block->ipa & 0x00f0) >> 4;
	int r3 = vcpu->arch.sie_block->ipa & 0x000f;
	int base2 = vcpu->arch.sie_block->ipb >> 28;
	int disp2 = ((vcpu->arch.sie_block->ipb & 0x0fff0000) >> 16);
	u32 parameter;
	u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
	u8 order_code;
	int rc;

	/* sigp in userspace can exit */
	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
	return kvm_s390_inject_program_int(vcpu,
	PGM_PRIVILEGED_OPERATION);

	order_code = disp2;
	if (base2)
	order_code += vcpu->run->s.regs.gprs[base2];

	if (r1 % 2)
	parameter = vcpu->run->s.regs.gprs[r1];
	else
	parameter = vcpu->run->s.regs.gprs[r1 + 1];

	switch (order_code) {
	case SIGP_SENSE:
	vcpu->stat.instruction_sigp_sense++;
	rc = __sigp_sense(vcpu, cpu_addr,
	&vcpu->run->s.regs.gprs[r1]);
	break;
	case SIGP_EXTERNAL_CALL:
	vcpu->stat.instruction_sigp_external_call++;
	rc = __sigp_external_call(vcpu, cpu_addr);
	break;
	case SIGP_EMERGENCY:
	vcpu->stat.instruction_sigp_emergency++;
	rc = __sigp_emergency(vcpu, cpu_addr);
	break;
	case SIGP_STOP:
	vcpu->stat.instruction_sigp_stop++;
	rc = __sigp_stop(vcpu, cpu_addr, ACTION_STOP_ON_STOP);
	break;
	case SIGP_STOP_STORE_STATUS:
	vcpu->stat.instruction_sigp_stop++;
	rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP \|
	ACTION_STOP_ON_STOP);
	break;
	case SIGP_SET_ARCH:
	vcpu->stat.instruction_sigp_arch++;
	rc = __sigp_set_arch(vcpu, parameter);
	break;
	case SIGP_SET_PREFIX:
	vcpu->stat.instruction_sigp_prefix++;
	rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
	&vcpu->run->s.regs.gprs[r1]);
	break;
	case SIGP_SENSE_RUNNING:
	vcpu->stat.instruction_sigp_sense_running++;
	rc = __sigp_sense_running(vcpu, cpu_addr,
	&vcpu->run->s.regs.gprs[r1]);
	break;
	case SIGP_RESTART:
	vcpu->stat.instruction_sigp_restart++;
	rc = __sigp_restart(vcpu, cpu_addr);
	if (rc == 2) /* busy */
	break;
	/* user space must know about restart */
	default:
	return -EOPNOTSUPP;
	}

	if (rc < 0)
	return rc;

	vcpu->arch.sie_block->gpsw.mask &= ~(3ul << 44);
	vcpu->arch.sie_block->gpsw.mask \|= (rc & 3ul) << 44;
	return 0;
	}