1 files changed, 28 insertions, 0 deletions

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index c1c7c683fa26..ef4ef21f2c73 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -454,6 +454,34 @@ int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
         return 0;
 }
 
+void s390_vcpu_block(struct kvm_vcpu *vcpu)
+{
+        atomic_set_mask(PROG_BLOCK_SIE, &vcpu->arch.sie_block->prog20);
+}
+
+void s390_vcpu_unblock(struct kvm_vcpu *vcpu)
+{
+        atomic_clear_mask(PROG_BLOCK_SIE, &vcpu->arch.sie_block->prog20);
+}
+
+/*
+ * Kick a guest cpu out of SIE and wait until SIE is not running.
+ * If the CPU is not running (e.g. waiting as idle) the function will
+ * return immediately. */
+void exit_sie(struct kvm_vcpu *vcpu)
+{
+        atomic_set_mask(CPUSTAT_STOP_INT, &vcpu->arch.sie_block->cpuflags);
+        while (vcpu->arch.sie_block->prog0c & PROG_IN_SIE)
+                cpu_relax();
+}
+
+/* Kick a guest cpu out of SIE and prevent SIE-reentry */
+void exit_sie_sync(struct kvm_vcpu *vcpu)
+{
+        s390_vcpu_block(vcpu);
+        exit_sie(vcpu);
+}
+
 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
 {
         /* kvm common code refers to this, but never calls it */