path: root/arch/s390/kvm/priv.c

/*
 * handling privileged instructions
 *
 * 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>
 */

#include <linux/kvm.h>
#include <linux/gfp.h>
#include <linux/errno.h>
#include <linux/compat.h>
#include <asm/asm-offsets.h>
#include <asm/facility.h>
#include <asm/current.h>
#include <asm/debug.h>
#include <asm/ebcdic.h>
#include <asm/sysinfo.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/io.h>
#include <asm/ptrace.h>
#include <asm/compat.h>
#include "gaccess.h"
#include "kvm-s390.h"
#include "trace.h"

/* Handle SCK (SET CLOCK) interception */
static int handle_set_clock(struct kvm_vcpu *vcpu)
{
	int rc;
	ar_t ar;
	u64 op2, val;

	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
		return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

	op2 = kvm_s390_get_base_disp_s(vcpu, &ar);
	if (op2 & 7)	/* Operand must be on a doubleword boundary */
		return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);
	rc = read_guest(vcpu, op2, ar, &val, sizeof(val));
	if (rc)
		return kvm_s390_inject_prog_cond(vcpu, rc);

	VCPU_EVENT(vcpu, 3, "SCK: setting guest TOD to 0x%llx", val);
	kvm_s390_set_tod_clock(vcpu->kvm, val);

	kvm_s390_set_psw_cc(vcpu, 0);
	return 0;
}

static int handle_set_prefix(struct kvm_vcpu *vcpu)
{
	u64 operand2;
	u32 address;
	int rc;
	ar_t ar;

	vcpu->stat.instruction_spx++;

	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
		return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

	operand2 = kvm_s390_get_base_disp_s(vcpu, &ar);

	/* must be word boundary */
	if (operand2 & 3)
		return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

	/* get the value */
	rc = read_guest(vcpu, operand2, ar, &address, sizeof(address));
	if (rc)
		return kvm_s390_inject_prog_cond(vcpu, rc);

	address &= 0x7fffe000u;

	/*
	 * 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.
	 */
	if (kvm_is_error_gpa(vcpu->kvm, address))
		return kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING);

	kvm_s390_set_prefix(vcpu, address);
	trace_kvm_s390_handle_prefix(vcpu, 1, address);
	return 0;
}

static int handle_store_prefix(struct kvm_vcpu *vcpu)
{
	u64 operand2;
	u32 address;
	int rc;
	ar_t ar;

	vcpu->stat.instruction_stpx++;

	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
		return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

	operand2 = kvm_s390_get_base_disp_s(vcpu, &ar);

	/* must be word boundary */
	if (operand2 & 3)
		return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

	address = kvm_s390_get_prefix(vcpu);

	/* get the value */
	rc = write_guest(vcpu, operand2, ar, &address, sizeof(address));
	if (rc)
		return kvm_s390_inject_prog_cond(vcpu, rc);

	VCPU_EVENT(vcpu, 3, "STPX: storing prefix 0x%x into 0x%llx", address, operand2);
	trace_kvm_s390_handle_prefix(vcpu, 0, address);
	return 0;
}

static int handle_store_cpu_address(struct kvm_vcpu *vcpu)
{
	u16 vcpu_id = vcpu->vcpu_id;
	u64 ga;
	int rc;
	ar_t ar;

	vcpu->stat.instruction_stap++;

	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)
		return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP);

	ga = kvm_s390_get_base_disp_s(vcpu, &ar);

	if (ga & 1)
		return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION);

	rc = write_guest(vcpu, ga, ar, &vcpu_id, sizeof(vcpu_id));
	if (rc)
		return kvm_s390_inject_prog_cond(vcpu, rc);

	VCPU_EVENT(vcpu, 3, "STAP: storing cpu address (%u) to 0x%llx", vcpu_id, ga);
	trace_kvm_s390_handle_stap(vcpu, ga);
	return 0;
}

static int __skey_check_enable(struct kvm_vcpu *vcpu)
{
	int rc = 0;
	if (!(vcpu->arch.sie_block->ictl & (ICTL_ISKE | ICTL_SSKE | ICTL_RRBE)))
		return rc;

	rc = s390_enable_skey();
	VCPU_EVENT(vcpu, 3, "%s", "enabling storage keys for guest");
	trace_kvm_s390_skey_related_inst(vcpu);
	vcpu->arch.sie_block->ictl &= ~(ICTL_ISKE | ICTL_SSKE | ICTL_RRBE);
	return rc;
}


static int handle_skey(struct kvm_vcpu *vcpu)
{
	int rc = __skey_check_enable(vcpu);

	if (rc)
		return rc;
	vcpu->stat.instruction_storage_key++;

	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)