KVM: s390: sigp: dispatch orders with one target in a separate function

All sigp orders except SIGP SET ARCHITECTURE target exactly one vcpu.

Let's move the dispatch code for these orders into a separate function to
prepare for cleaner target availability checks.
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

arch/s390/kvm/sigp.c

@@ -349,32 +349,15 @@ static int sigp_check_callable(struct kvm_vcpu *vcpu, u16 cpu_addr)
 	return rc;
 }
 
-int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
+static int handle_sigp_dst(struct kvm_vcpu *vcpu, u8 order_code,
+			   u16 cpu_addr, u32 parameter, u64 *status_reg)
 {
-	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]);
+		rc = __sigp_sense(vcpu, cpu_addr, status_reg);
 		break;
 	case SIGP_EXTERNAL_CALL:
 		vcpu->stat.instruction_sigp_external_call++;
@@ -395,25 +378,19 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 		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);
+						 status_reg);
 		break;
 	case SIGP_SET_PREFIX:
 		vcpu->stat.instruction_sigp_prefix++;
-		rc = __sigp_set_prefix(vcpu, cpu_addr, parameter,
-				       &vcpu->run->s.regs.gprs[r1]);
+		rc = __sigp_set_prefix(vcpu, cpu_addr, parameter, status_reg);
 		break;
 	case SIGP_COND_EMERGENCY_SIGNAL:
 		rc = __sigp_conditional_emergency(vcpu, cpu_addr, parameter,
-						  &vcpu->run->s.regs.gprs[r1]);
+						  status_reg);
 		break;
 	case SIGP_SENSE_RUNNING:
 		vcpu->stat.instruction_sigp_sense_running++;
-		rc = __sigp_sense_running(vcpu, cpu_addr,
-					  &vcpu->run->s.regs.gprs[r1]);
+		rc = __sigp_sense_running(vcpu, cpu_addr, status_reg);
 		break;
 	case SIGP_START:
 		rc = sigp_check_callable(vcpu, cpu_addr);
@@ -432,7 +409,42 @@ int kvm_s390_handle_sigp(struct kvm_vcpu *vcpu)
 		}
 		break;
 	default:
-		return -EOPNOTSUPP;
+		rc = -EOPNOTSUPP;
+	}
+
+	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_SET_ARCHITECTURE:
+		vcpu->stat.instruction_sigp_arch++;
+		rc = __sigp_set_arch(vcpu, parameter);
+		break;
+	default:
+		rc = handle_sigp_dst(vcpu, order_code, cpu_addr,
+				     parameter,
+				     &vcpu->run->s.regs.gprs[r1]);
 	}
 
 	if (rc < 0)