KVM: s390: provide functions for blocking all CPUs

Some updates to the control blocks need to be done in a way that
ensures that no CPU is within SIE. Provide wrappers around the
s390_vcpu_block functions and adopt the TOD migration code to
update in a guaranteed fashion. Also rename these functions to
have the kvm_s390_ prefix as everything else.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index 8edca85..c570478 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -211,8 +211,8 @@
 int kvm_s390_vcpu_store_adtl_status(struct kvm_vcpu *vcpu, unsigned long addr);
 void kvm_s390_vcpu_start(struct kvm_vcpu *vcpu);
 void kvm_s390_vcpu_stop(struct kvm_vcpu *vcpu);
-void s390_vcpu_block(struct kvm_vcpu *vcpu);
-void s390_vcpu_unblock(struct kvm_vcpu *vcpu);
+void kvm_s390_vcpu_block(struct kvm_vcpu *vcpu);
+void kvm_s390_vcpu_unblock(struct kvm_vcpu *vcpu);
 void exit_sie(struct kvm_vcpu *vcpu);
 void kvm_s390_sync_request(int req, struct kvm_vcpu *vcpu);
 int kvm_s390_vcpu_setup_cmma(struct kvm_vcpu *vcpu);
@@ -228,6 +228,25 @@
 int kvm_s390_inject_prog_irq(struct kvm_vcpu *vcpu,
 			     struct kvm_s390_pgm_info *pgm_info);
 
+static inline void kvm_s390_vcpu_block_all(struct kvm *kvm)
+{
+	int i;
+	struct kvm_vcpu *vcpu;
+
+	WARN_ON(!mutex_is_locked(&kvm->lock));
+	kvm_for_each_vcpu(i, vcpu, kvm)
+		kvm_s390_vcpu_block(vcpu);
+}
+
+static inline void kvm_s390_vcpu_unblock_all(struct kvm *kvm)
+{
+	int i;
+	struct kvm_vcpu *vcpu;
+
+	kvm_for_each_vcpu(i, vcpu, kvm)
+		kvm_s390_vcpu_unblock(vcpu);
+}
+
 /**
  * kvm_s390_inject_prog_cond - conditionally inject a program check
  * @vcpu: virtual cpu