commit e6db1d61c7cc05dd3c8b787a0bd47dcb94800300
author Dominik Dingel <dingel@linux.vnet.ibm.com> Thu May 07 15:41:57 2015 +0200
committer Christian Borntraeger <borntraeger@de.ibm.com> Wed Jul 29 11:02:05 2015 +0200
tree f7cc9f1c33d9866bd111e881eb899eae74047d47
parent 0df30abcd69b61d8163282c157f15ed3b0f1ac85

KVM: s390: clean up cmma_enable check

As we already only enable CMMA when userspace requests it, we can
safely move the additional checks to the request handler and avoid
doing them multiple times. This also tells userspace if CMMA is
available.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

arch/s390/kvm/kvm-s390.c

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index b77dcfe..641639b 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -330,6 +330,11 @@
 	unsigned int idx;
 	switch (attr->attr) {
 	case KVM_S390_VM_MEM_ENABLE_CMMA:
+		/* enable CMMA only for z10 and later (EDAT_1) */
+		ret = -EINVAL;
+		if (!MACHINE_IS_LPAR || !MACHINE_HAS_EDAT1)
+			break;
+
 		ret = -EBUSY;
 		mutex_lock(&kvm->lock);
 		if (atomic_read(&kvm->online_vcpus) == 0) {
@@ -1133,7 +1138,7 @@
 	if (kvm_is_ucontrol(vcpu->kvm))
 		gmap_free(vcpu->arch.gmap);
 
-	if (kvm_s390_cmma_enabled(vcpu->kvm))
+	if (vcpu->kvm->arch.use_cmma)
 		kvm_s390_vcpu_unsetup_cmma(vcpu);
 	free_page((unsigned long)(vcpu->arch.sie_block));
 
@@ -1344,7 +1349,7 @@
 	}
 	vcpu->arch.sie_block->ictl |= ICTL_ISKE | ICTL_SSKE | ICTL_RRBE;
 
-	if (kvm_s390_cmma_enabled(vcpu->kvm)) {
+	if (vcpu->kvm->arch.use_cmma) {
 		rc = kvm_s390_vcpu_setup_cmma(vcpu);
 		if (rc)
 			return rc;
@@ -1725,18 +1730,6 @@
 	return rc;
 }
 
-bool kvm_s390_cmma_enabled(struct kvm *kvm)
-{
-	if (!MACHINE_IS_LPAR)
-		return false;
-	/* only enable for z10 and later */
-	if (!MACHINE_HAS_EDAT1)
-		return false;
-	if (!kvm->arch.use_cmma)
-		return false;
-	return true;
-}
-
 static bool ibs_enabled(struct kvm_vcpu *vcpu)
 {
 	return atomic_read(&vcpu->arch.sie_block->cpuflags) & CPUSTAT_IBS;

arch/s390/kvm/kvm-s390.h

diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index c570478..81de2af 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -217,8 +217,6 @@
 void kvm_s390_sync_request(int req, struct kvm_vcpu *vcpu);
 int kvm_s390_vcpu_setup_cmma(struct kvm_vcpu *vcpu);
 void kvm_s390_vcpu_unsetup_cmma(struct kvm_vcpu *vcpu);
-/* is cmma enabled */
-bool kvm_s390_cmma_enabled(struct kvm *kvm);
 unsigned long kvm_s390_fac_list_mask_size(void);
 extern unsigned long kvm_s390_fac_list_mask[];
 

arch/s390/kvm/priv.c

diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c
index ad42422..1b95d29 100644
--- a/arch/s390/kvm/priv.c
+++ b/arch/s390/kvm/priv.c
@@ -761,7 +761,7 @@
 	VCPU_EVENT(vcpu, 5, "cmma release %d pages", entries);
 	gmap = vcpu->arch.gmap;
 	vcpu->stat.instruction_essa++;
-	if (!kvm_s390_cmma_enabled(vcpu->kvm))
+	if (!vcpu->kvm->arch.use_cmma)
 		return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
 
 	if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE)