KVM: s390: sie intercept handling

This path introduces handling of sie intercepts in three flavors: Intercepts
are either handled completely in-kernel by kvm_handle_sie_intercept(),
or passed to userspace with corresponding data in struct kvm_run in case
kvm_handle_sie_intercept() returns -ENOTSUPP.
In case of partial execution in kernel with the need of userspace support,
kvm_handle_sie_intercept() may choose to set up struct kvm_run and return
-EREMOTE.

The trivial intercept reasons are handled in this patch:
handle_noop() just does nothing for intercepts that don't require our support
  at all
handle_stop() is called when a cpu enters stopped state, and it drops out to
  userland after updating our vcpu state
handle_validity() faults in the cpu lowcore if needed, or passes the request
  to userland

Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/asm-s390/kvm_host.h b/include/asm-s390/kvm_host.h
index c9d6533..8965b38 100644
--- a/include/asm-s390/kvm_host.h
+++ b/include/asm-s390/kvm_host.h
@@ -101,6 +101,10 @@ struct sie_block {
 
 struct kvm_vcpu_stat {
 	u32 exit_userspace;
+	u32 exit_external_request;
+	u32 exit_external_interrupt;
+	u32 exit_stop_request;
+	u32 exit_validity;
 };
 
 struct kvm_vcpu_arch {