arch/s390/kvm/sigp.c - pub/scm/linux/kernel/git/luto/devel - Git at Google

 /*
  * handling interprocessor communication
  *
  * Copyright IBM Corp. 2008, 2013
  *
  * 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 <asm/sigp.h>
 #include "gaccess.h"
 #include "kvm-s390.h"
 #include "trace.h"

 static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
 			u64 *reg)
 {
 	struct kvm_s390_local_interrupt *li;
 	struct kvm_vcpu *dst_vcpu = NULL;
 	int cpuflags;
 	int rc;

 	if (cpu_addr >= KVM_MAX_VCPUS)
 		return SIGP_CC_NOT_OPERATIONAL;

 	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
 	if (!dst_vcpu)
 		return SIGP_CC_NOT_OPERATIONAL;
 	li = &dst_vcpu->arch.local_int;

 	cpuflags = atomic_read(li->cpuflags);
 	if (!(cpuflags & (CPUSTAT_ECALL_PEND | CPUSTAT_STOPPED)))
 		rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 	else {
 		*reg &= 0xffffffff00000000UL;
 		if (cpuflags & CPUSTAT_ECALL_PEND)
 			*reg |= SIGP_STATUS_EXT_CALL_PENDING;
 		if (cpuflags & CPUSTAT_STOPPED)
 			*reg |= SIGP_STATUS_STOPPED;
 		rc = SIGP_CC_STATUS_STORED;
 	}

 	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_interrupt s390int = {
 		.type = KVM_S390_INT_EMERGENCY,
 		.parm = vcpu->vcpu_id,
 	};
 	struct kvm_vcpu *dst_vcpu = NULL;
 	int rc = 0;

 	if (cpu_addr < KVM_MAX_VCPUS)
 		dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
 	if (!dst_vcpu)
 		return SIGP_CC_NOT_OPERATIONAL;

 	rc = kvm_s390_inject_vcpu(dst_vcpu, &s390int);
 	if (!rc)
 		VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);

 	return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED;
 }

 static int __sigp_conditional_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr,
 					u16 asn, u64 *reg)
 {
 	struct kvm_vcpu *dst_vcpu = NULL;
 	const u64 psw_int_mask = PSW_MASK_IO | PSW_MASK_EXT;
 	u16 p_asn, s_asn;
 	psw_t *psw;
 	u32 flags;

 	if (cpu_addr < KVM_MAX_VCPUS)
 		dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
 	if (!dst_vcpu)
 		return SIGP_CC_NOT_OPERATIONAL;
 	flags = atomic_read(&dst_vcpu->arch.sie_block->cpuflags);
 	psw = &dst_vcpu->arch.sie_block->gpsw;
 	p_asn = dst_vcpu->arch.sie_block->gcr[4] & 0xffff;  /* Primary ASN */
 	s_asn = dst_vcpu->arch.sie_block->gcr[3] & 0xffff;  /* Secondary ASN */

 	/* Deliver the emergency signal? */
 	if (!(flags & CPUSTAT_STOPPED)
 	    || (psw->mask & psw_int_mask) != psw_int_mask
 	    || ((flags & CPUSTAT_WAIT) && psw->addr != 0)
 	    || (!(flags & CPUSTAT_WAIT) && (asn == p_asn || asn == s_asn))) {
 		return __sigp_emergency(vcpu, cpu_addr);
 	} else {
 		*reg &= 0xffffffff00000000UL;
 		*reg |= SIGP_STATUS_INCORRECT_STATE;
 		return SIGP_CC_STATUS_STORED;
 	}
 }

 static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr)
 {
 	struct kvm_s390_interrupt s390int = {
 		.type = KVM_S390_INT_EXTERNAL_CALL,
 		.parm = vcpu->vcpu_id,
 	};
 	struct kvm_vcpu *dst_vcpu = NULL;
 	int rc;

 	if (cpu_addr < KVM_MAX_VCPUS)
 		dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
 	if (!dst_vcpu)
 		return SIGP_CC_NOT_OPERATIONAL;

 	rc = kvm_s390_inject_vcpu(dst_vcpu, &s390int);
 	if (!rc)
 		VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x", cpu_addr);

 	return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED;
 }

 static int __inject_sigp_stop(struct kvm_vcpu *dst_vcpu, int action)
 {
 	struct kvm_s390_local_interrupt *li = &dst_vcpu->arch.local_int;
 	struct kvm_s390_interrupt_info *inti;
 	int rc = SIGP_CC_ORDER_CODE_ACCEPTED;

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

 	spin_lock(&li->lock);
 	if (li->action_bits & ACTION_STOP_ON_STOP) {
 		/* another SIGP STOP is pending */
 		kfree(inti);
 		rc = SIGP_CC_BUSY;
 		goto out;
 	}
 	if ((atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
 		kfree(inti);
 		if ((action & ACTION_STORE_ON_STOP) != 0)
 			rc = -ESHUTDOWN;
 		goto out;
 	}
 	list_add_tail(&inti->list, &li->list);
 	atomic_set(&li->active, 1);
 	li->action_bits |= action;
 	atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
 	kvm_s390_vcpu_wakeup(dst_vcpu);
 out:
 	spin_unlock(&li->lock);

 	return rc;
 }

 static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
 {
 	struct kvm_vcpu *dst_vcpu = NULL;
 	int rc;

 	if (cpu_addr >= KVM_MAX_VCPUS)
 		return SIGP_CC_NOT_OPERATIONAL;

 	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
 	if (!dst_vcpu)
 		return SIGP_CC_NOT_OPERATIONAL;

 	rc = __inject_sigp_stop(dst_vcpu, action);

 	VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);

 	if ((action & ACTION_STORE_ON_STOP) != 0 && rc == -ESHUTDOWN) {
 		/* If the CPU has already been stopped, we still have
 		 * to save the status when doing stop-and-store. This
 		 * has to be done after unlocking all spinlocks. */
 		rc = kvm_s390_store_status_unloaded(dst_vcpu,
 						KVM_S390_STORE_STATUS_NOADDR);
 	}

 	return rc;
 }

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

 	switch (parameter & 0xff) {
 	case 0:
 		rc = SIGP_CC_NOT_OPERATIONAL;
 		break;
 	case 1:
 	case 2:
 		kvm_for_each_vcpu(i, v, vcpu->kvm) {
 			v->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
 			kvm_clear_async_pf_completion_queue(v);
 		}

 		rc = SIGP_CC_ORDER_CODE_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_local_interrupt *li;
 	struct kvm_vcpu *dst_vcpu = NULL;
 	struct kvm_s390_interrupt_info *inti;
 	int rc;

 	if (cpu_addr < KVM_MAX_VCPUS)
 		dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
 	if (!dst_vcpu)
 		return SIGP_CC_NOT_OPERATIONAL;
 	li = &dst_vcpu->arch.local_int;

 	/*
 	 * Make sure the new value is valid memory. We only need to check the
 	 * first page, since address is 8k aligned and memory pieces are always
 	 * at least 1MB aligned and have at least a size of 1MB.
 	 */
 	address &= 0x7fffe000u;
 	if (kvm_is_error_gpa(vcpu->kvm, address)) {
 		*reg &= 0xffffffff00000000UL;
 		*reg |= SIGP_STATUS_INVALID_PARAMETER;
 		return SIGP_CC_STATUS_STORED;
 	}

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

 	spin_lock(&li->lock);
 	/* cpu must be in stopped state */
 	if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
 		*reg &= 0xffffffff00000000UL;
 		*reg |= SIGP_STATUS_INCORRECT_STATE;
 		rc = SIGP_CC_STATUS_STORED;
 		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);
 	kvm_s390_vcpu_wakeup(dst_vcpu);
 	rc = SIGP_CC_ORDER_CODE_ACCEPTED;

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

 static int __sigp_store_status_at_addr(struct kvm_vcpu *vcpu, u16 cpu_id,
 					u32 addr, u64 *reg)
 {
 	struct kvm_vcpu *dst_vcpu = NULL;
 	int flags;
 	int rc;

 	if (cpu_id < KVM_MAX_VCPUS)
 		dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_id);
 	if (!dst_vcpu)
 		return SIGP_CC_NOT_OPERATIONAL;

 	spin_lock(&dst_vcpu->arch.local_int.lock);
 	flags = atomic_read(dst_vcpu->arch.local_int.cpuflags);
 	spin_unlock(&dst_vcpu->arch.local_int.lock);
 	if (!(flags & CPUSTAT_STOPPED)) {
 		*reg &= 0xffffffff00000000UL;
 		*reg |= SIGP_STATUS_INCORRECT_STATE;
 		return SIGP_CC_STATUS_STORED;
 	}

 	addr &= 0x7ffffe00;
 	rc = kvm_s390_store_status_unloaded(dst_vcpu, addr);
 	if (rc == -EFAULT) {
 		*reg &= 0xffffffff00000000UL;
 		*reg |= SIGP_STATUS_INVALID_PARAMETER;
 		rc = SIGP_CC_STATUS_STORED;
 	}
 	return rc;
 }

 static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
 				u64 *reg)
 {
 	struct kvm_s390_local_interrupt *li;
 	struct kvm_vcpu *dst_vcpu = NULL;
 	int rc;

 	if (cpu_addr >= KVM_MAX_VCPUS)
 		return SIGP_CC_NOT_OPERATIONAL;

 	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
 	if (!dst_vcpu)
 		return SIGP_CC_NOT_OPERATIONAL;
 	li = &dst_vcpu->arch.local_int;
 	if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) {
 		/* running */
 		rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 	} else {
 		/* not running */
 		*reg &= 0xffffffff00000000UL;
 		*reg |= SIGP_STATUS_NOT_RUNNING;
 		rc = SIGP_CC_STATUS_STORED;
 	}

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

 	return rc;
 }

 /* Test whether the destination CPU is available and not busy */
 static int sigp_check_callable(struct kvm_vcpu *vcpu, u16 cpu_addr)
 {
 	struct kvm_s390_local_interrupt *li;
 	int rc = SIGP_CC_ORDER_CODE_ACCEPTED;
 	struct kvm_vcpu *dst_vcpu = NULL;

 	if (cpu_addr >= KVM_MAX_VCPUS)
 		return SIGP_CC_NOT_OPERATIONAL;

 	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
 	if (!dst_vcpu)
 		return SIGP_CC_NOT_OPERATIONAL;
 	li = &dst_vcpu->arch.local_int;
 	spin_lock(&li->lock);
 	if (li->action_bits & ACTION_STOP_ON_STOP)
 		rc = SIGP_CC_BUSY;
 	spin_unlock(&li->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;
 	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_OP);

 	order_code = kvm_s390_get_base_disp_rs(vcpu);

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

 	trace_kvm_s390_handle_sigp(vcpu, order_code, cpu_addr, parameter);
 	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_SIGNAL:
 		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_AND_STORE_STATUS:
 		vcpu->stat.instruction_sigp_stop++;
 		rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP |
 						 ACTION_STOP_ON_STOP);
 		break;
 	case SIGP_STORE_STATUS_AT_ADDRESS:
 		rc = __sigp_store_status_at_addr(vcpu, cpu_addr, parameter,
 						 &vcpu->run->s.regs.gprs[r1]);
 		break;
 	case SIGP_SET_ARCHITECTURE:
 		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_COND_EMERGENCY_SIGNAL:
 		rc = __sigp_conditional_emergency(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_START:
 		rc = sigp_check_callable(vcpu, cpu_addr);
 		if (rc == SIGP_CC_ORDER_CODE_ACCEPTED)
 			rc = -EOPNOTSUPP;    /* Handle START in user space */
 		break;
 	case SIGP_RESTART:
 		vcpu->stat.instruction_sigp_restart++;
 		rc = sigp_check_callable(vcpu, cpu_addr);
 		if (rc == SIGP_CC_ORDER_CODE_ACCEPTED) {
 			VCPU_EVENT(vcpu, 4,
 				   "sigp restart %x to handle userspace",
 				   cpu_addr);
 			/* user space must know about restart */
 			rc = -EOPNOTSUPP;
 		}
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}

 	if (rc < 0)
 		return rc;

 	kvm_s390_set_psw_cc(vcpu, rc);
 	return 0;
 }

 /*
  * Handle SIGP partial execution interception.
  *
  * This interception will occur at the source cpu when a source cpu sends an
  * external call to a target cpu and the target cpu has the WAIT bit set in
  * its cpuflags. Interception will occurr after the interrupt indicator bits at
  * the target cpu have been set. All error cases will lead to instruction
  * interception, therefore nothing is to be checked or prepared.
  */
 int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu)
 {
 	int r3 = vcpu->arch.sie_block->ipa & 0x000f;
 	u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
 	struct kvm_vcpu *dest_vcpu;
 	u8 order_code = kvm_s390_get_base_disp_rs(vcpu);

 	trace_kvm_s390_handle_sigp_pei(vcpu, order_code, cpu_addr);

 	if (order_code == SIGP_EXTERNAL_CALL) {
 		dest_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
 		BUG_ON(dest_vcpu == NULL);

 		kvm_s390_vcpu_wakeup(dest_vcpu);
 		kvm_s390_set_psw_cc(vcpu, SIGP_CC_ORDER_CODE_ACCEPTED);
 		return 0;
 	}

 	return -EOPNOTSUPP;
 }
	/*
	* handling interprocessor communication
	*
	* Copyright IBM Corp. 2008, 2013
	*
	* 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 <asm/sigp.h>
	#include "gaccess.h"
	#include "kvm-s390.h"
	#include "trace.h"

	static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
	u64 *reg)
	{
	struct kvm_s390_local_interrupt *li;
	struct kvm_vcpu *dst_vcpu = NULL;
	int cpuflags;
	int rc;

	if (cpu_addr >= KVM_MAX_VCPUS)
	return SIGP_CC_NOT_OPERATIONAL;

	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
	if (!dst_vcpu)
	return SIGP_CC_NOT_OPERATIONAL;
	li = &dst_vcpu->arch.local_int;

	cpuflags = atomic_read(li->cpuflags);
	if (!(cpuflags & (CPUSTAT_ECALL_PEND \| CPUSTAT_STOPPED)))
	rc = SIGP_CC_ORDER_CODE_ACCEPTED;
	else {
	*reg &= 0xffffffff00000000UL;
	if (cpuflags & CPUSTAT_ECALL_PEND)
	*reg \|= SIGP_STATUS_EXT_CALL_PENDING;
	if (cpuflags & CPUSTAT_STOPPED)
	*reg \|= SIGP_STATUS_STOPPED;
	rc = SIGP_CC_STATUS_STORED;
	}

	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_interrupt s390int = {
	.type = KVM_S390_INT_EMERGENCY,
	.parm = vcpu->vcpu_id,
	};
	struct kvm_vcpu *dst_vcpu = NULL;
	int rc = 0;

	if (cpu_addr < KVM_MAX_VCPUS)
	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
	if (!dst_vcpu)
	return SIGP_CC_NOT_OPERATIONAL;

	rc = kvm_s390_inject_vcpu(dst_vcpu, &s390int);
	if (!rc)
	VCPU_EVENT(vcpu, 4, "sent sigp emerg to cpu %x", cpu_addr);

	return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED;
	}

	static int __sigp_conditional_emergency(struct kvm_vcpu *vcpu, u16 cpu_addr,
	u16 asn, u64 *reg)
	{
	struct kvm_vcpu *dst_vcpu = NULL;
	const u64 psw_int_mask = PSW_MASK_IO \| PSW_MASK_EXT;
	u16 p_asn, s_asn;
	psw_t *psw;
	u32 flags;

	if (cpu_addr < KVM_MAX_VCPUS)
	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
	if (!dst_vcpu)
	return SIGP_CC_NOT_OPERATIONAL;
	flags = atomic_read(&dst_vcpu->arch.sie_block->cpuflags);
	psw = &dst_vcpu->arch.sie_block->gpsw;
	p_asn = dst_vcpu->arch.sie_block->gcr[4] & 0xffff; /* Primary ASN */
	s_asn = dst_vcpu->arch.sie_block->gcr[3] & 0xffff; /* Secondary ASN */

	/* Deliver the emergency signal? */
	if (!(flags & CPUSTAT_STOPPED)
	\|\| (psw->mask & psw_int_mask) != psw_int_mask
	\|\| ((flags & CPUSTAT_WAIT) && psw->addr != 0)
	\|\| (!(flags & CPUSTAT_WAIT) && (asn == p_asn \|\| asn == s_asn))) {
	return __sigp_emergency(vcpu, cpu_addr);
	} else {
	*reg &= 0xffffffff00000000UL;
	*reg \|= SIGP_STATUS_INCORRECT_STATE;
	return SIGP_CC_STATUS_STORED;
	}
	}

	static int __sigp_external_call(struct kvm_vcpu *vcpu, u16 cpu_addr)
	{
	struct kvm_s390_interrupt s390int = {
	.type = KVM_S390_INT_EXTERNAL_CALL,
	.parm = vcpu->vcpu_id,
	};
	struct kvm_vcpu *dst_vcpu = NULL;
	int rc;

	if (cpu_addr < KVM_MAX_VCPUS)
	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
	if (!dst_vcpu)
	return SIGP_CC_NOT_OPERATIONAL;

	rc = kvm_s390_inject_vcpu(dst_vcpu, &s390int);
	if (!rc)
	VCPU_EVENT(vcpu, 4, "sent sigp ext call to cpu %x", cpu_addr);

	return rc ? rc : SIGP_CC_ORDER_CODE_ACCEPTED;
	}

	static int __inject_sigp_stop(struct kvm_vcpu *dst_vcpu, int action)
	{
	struct kvm_s390_local_interrupt *li = &dst_vcpu->arch.local_int;
	struct kvm_s390_interrupt_info *inti;
	int rc = SIGP_CC_ORDER_CODE_ACCEPTED;

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

	spin_lock(&li->lock);
	if (li->action_bits & ACTION_STOP_ON_STOP) {
	/* another SIGP STOP is pending */
	kfree(inti);
	rc = SIGP_CC_BUSY;
	goto out;
	}
	if ((atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
	kfree(inti);
	if ((action & ACTION_STORE_ON_STOP) != 0)
	rc = -ESHUTDOWN;
	goto out;
	}
	list_add_tail(&inti->list, &li->list);
	atomic_set(&li->active, 1);
	li->action_bits \|= action;
	atomic_set_mask(CPUSTAT_STOP_INT, li->cpuflags);
	kvm_s390_vcpu_wakeup(dst_vcpu);
	out:
	spin_unlock(&li->lock);

	return rc;
	}

	static int __sigp_stop(struct kvm_vcpu *vcpu, u16 cpu_addr, int action)
	{
	struct kvm_vcpu *dst_vcpu = NULL;
	int rc;

	if (cpu_addr >= KVM_MAX_VCPUS)
	return SIGP_CC_NOT_OPERATIONAL;

	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
	if (!dst_vcpu)
	return SIGP_CC_NOT_OPERATIONAL;

	rc = __inject_sigp_stop(dst_vcpu, action);

	VCPU_EVENT(vcpu, 4, "sent sigp stop to cpu %x", cpu_addr);

	if ((action & ACTION_STORE_ON_STOP) != 0 && rc == -ESHUTDOWN) {
	/* If the CPU has already been stopped, we still have
	* to save the status when doing stop-and-store. This
	* has to be done after unlocking all spinlocks. */
	rc = kvm_s390_store_status_unloaded(dst_vcpu,
	KVM_S390_STORE_STATUS_NOADDR);
	}

	return rc;
	}

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

	switch (parameter & 0xff) {
	case 0:
	rc = SIGP_CC_NOT_OPERATIONAL;
	break;
	case 1:
	case 2:
	kvm_for_each_vcpu(i, v, vcpu->kvm) {
	v->arch.pfault_token = KVM_S390_PFAULT_TOKEN_INVALID;
	kvm_clear_async_pf_completion_queue(v);
	}

	rc = SIGP_CC_ORDER_CODE_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_local_interrupt *li;
	struct kvm_vcpu *dst_vcpu = NULL;
	struct kvm_s390_interrupt_info *inti;
	int rc;

	if (cpu_addr < KVM_MAX_VCPUS)
	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
	if (!dst_vcpu)
	return SIGP_CC_NOT_OPERATIONAL;
	li = &dst_vcpu->arch.local_int;

	/*
	* Make sure the new value is valid memory. We only need to check the
	* first page, since address is 8k aligned and memory pieces are always
	* at least 1MB aligned and have at least a size of 1MB.
	*/
	address &= 0x7fffe000u;
	if (kvm_is_error_gpa(vcpu->kvm, address)) {
	*reg &= 0xffffffff00000000UL;
	*reg \|= SIGP_STATUS_INVALID_PARAMETER;
	return SIGP_CC_STATUS_STORED;
	}

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

	spin_lock(&li->lock);
	/* cpu must be in stopped state */
	if (!(atomic_read(li->cpuflags) & CPUSTAT_STOPPED)) {
	*reg &= 0xffffffff00000000UL;
	*reg \|= SIGP_STATUS_INCORRECT_STATE;
	rc = SIGP_CC_STATUS_STORED;
	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);
	kvm_s390_vcpu_wakeup(dst_vcpu);
	rc = SIGP_CC_ORDER_CODE_ACCEPTED;

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

	static int __sigp_store_status_at_addr(struct kvm_vcpu *vcpu, u16 cpu_id,
	u32 addr, u64 *reg)
	{
	struct kvm_vcpu *dst_vcpu = NULL;
	int flags;
	int rc;

	if (cpu_id < KVM_MAX_VCPUS)
	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_id);
	if (!dst_vcpu)
	return SIGP_CC_NOT_OPERATIONAL;

	spin_lock(&dst_vcpu->arch.local_int.lock);
	flags = atomic_read(dst_vcpu->arch.local_int.cpuflags);
	spin_unlock(&dst_vcpu->arch.local_int.lock);
	if (!(flags & CPUSTAT_STOPPED)) {
	*reg &= 0xffffffff00000000UL;
	*reg \|= SIGP_STATUS_INCORRECT_STATE;
	return SIGP_CC_STATUS_STORED;
	}

	addr &= 0x7ffffe00;
	rc = kvm_s390_store_status_unloaded(dst_vcpu, addr);
	if (rc == -EFAULT) {
	*reg &= 0xffffffff00000000UL;
	*reg \|= SIGP_STATUS_INVALID_PARAMETER;
	rc = SIGP_CC_STATUS_STORED;
	}
	return rc;
	}

	static int __sigp_sense_running(struct kvm_vcpu *vcpu, u16 cpu_addr,
	u64 *reg)
	{
	struct kvm_s390_local_interrupt *li;
	struct kvm_vcpu *dst_vcpu = NULL;
	int rc;

	if (cpu_addr >= KVM_MAX_VCPUS)
	return SIGP_CC_NOT_OPERATIONAL;

	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
	if (!dst_vcpu)
	return SIGP_CC_NOT_OPERATIONAL;
	li = &dst_vcpu->arch.local_int;
	if (atomic_read(li->cpuflags) & CPUSTAT_RUNNING) {
	/* running */
	rc = SIGP_CC_ORDER_CODE_ACCEPTED;
	} else {
	/* not running */
	*reg &= 0xffffffff00000000UL;
	*reg \|= SIGP_STATUS_NOT_RUNNING;
	rc = SIGP_CC_STATUS_STORED;
	}

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

	return rc;
	}

	/* Test whether the destination CPU is available and not busy */
	static int sigp_check_callable(struct kvm_vcpu *vcpu, u16 cpu_addr)
	{
	struct kvm_s390_local_interrupt *li;
	int rc = SIGP_CC_ORDER_CODE_ACCEPTED;
	struct kvm_vcpu *dst_vcpu = NULL;

	if (cpu_addr >= KVM_MAX_VCPUS)
	return SIGP_CC_NOT_OPERATIONAL;

	dst_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
	if (!dst_vcpu)
	return SIGP_CC_NOT_OPERATIONAL;
	li = &dst_vcpu->arch.local_int;
	spin_lock(&li->lock);
	if (li->action_bits & ACTION_STOP_ON_STOP)
	rc = SIGP_CC_BUSY;
	spin_unlock(&li->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;
	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_OP);

	order_code = kvm_s390_get_base_disp_rs(vcpu);

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

	trace_kvm_s390_handle_sigp(vcpu, order_code, cpu_addr, parameter);
	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_SIGNAL:
	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_AND_STORE_STATUS:
	vcpu->stat.instruction_sigp_stop++;
	rc = __sigp_stop(vcpu, cpu_addr, ACTION_STORE_ON_STOP \|
	ACTION_STOP_ON_STOP);
	break;
	case SIGP_STORE_STATUS_AT_ADDRESS:
	rc = __sigp_store_status_at_addr(vcpu, cpu_addr, parameter,
	&vcpu->run->s.regs.gprs[r1]);
	break;
	case SIGP_SET_ARCHITECTURE:
	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_COND_EMERGENCY_SIGNAL:
	rc = __sigp_conditional_emergency(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_START:
	rc = sigp_check_callable(vcpu, cpu_addr);
	if (rc == SIGP_CC_ORDER_CODE_ACCEPTED)
	rc = -EOPNOTSUPP; /* Handle START in user space */
	break;
	case SIGP_RESTART:
	vcpu->stat.instruction_sigp_restart++;
	rc = sigp_check_callable(vcpu, cpu_addr);
	if (rc == SIGP_CC_ORDER_CODE_ACCEPTED) {
	VCPU_EVENT(vcpu, 4,
	"sigp restart %x to handle userspace",
	cpu_addr);
	/* user space must know about restart */
	rc = -EOPNOTSUPP;
	}
	break;
	default:
	return -EOPNOTSUPP;
	}

	if (rc < 0)
	return rc;

	kvm_s390_set_psw_cc(vcpu, rc);
	return 0;
	}

	/*
	* Handle SIGP partial execution interception.
	*
	* This interception will occur at the source cpu when a source cpu sends an
	* external call to a target cpu and the target cpu has the WAIT bit set in
	* its cpuflags. Interception will occurr after the interrupt indicator bits at
	* the target cpu have been set. All error cases will lead to instruction
	* interception, therefore nothing is to be checked or prepared.
	*/
	int kvm_s390_handle_sigp_pei(struct kvm_vcpu *vcpu)
	{
	int r3 = vcpu->arch.sie_block->ipa & 0x000f;
	u16 cpu_addr = vcpu->run->s.regs.gprs[r3];
	struct kvm_vcpu *dest_vcpu;
	u8 order_code = kvm_s390_get_base_disp_rs(vcpu);

	trace_kvm_s390_handle_sigp_pei(vcpu, order_code, cpu_addr);

	if (order_code == SIGP_EXTERNAL_CALL) {
	dest_vcpu = kvm_get_vcpu(vcpu->kvm, cpu_addr);
	BUG_ON(dest_vcpu == NULL);

	kvm_s390_vcpu_wakeup(dest_vcpu);
	kvm_s390_set_psw_cc(vcpu, SIGP_CC_ORDER_CODE_ACCEPTED);
	return 0;
	}

	return -EOPNOTSUPP;
	}