KVM: PPC: Convert SRR0 and SRR1 to shared page

The SRR0 and SRR1 registers contain cached values of the PC and MSR
respectively. They get written to by the hypervisor when an interrupt
occurs or directly by the kernel. They are also used to tell the rfi(d)
instruction where to jump to.

Because it only gets touched on defined events that, it's very simple to
share with the guest. Hypervisor and guest both have full r/w access.

This patch converts all users of the current field to the shared page.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 8 insertions, 4 deletions

diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c
index 4568ec386c2a..ad0fa4ff4ea0 100644
--- a/arch/powerpc/kvm/emulate.c
+++ b/arch/powerpc/kvm/emulate.c
@@ -242,9 +242,11 @@ int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu)
 
                         switch (sprn) {
                         case SPRN_SRR0:
-                                kvmppc_set_gpr(vcpu, rt, vcpu->arch.srr0); break;
+                                kvmppc_set_gpr(vcpu, rt, vcpu->arch.shared->srr0);
+                                break;
                         case SPRN_SRR1:
-                                kvmppc_set_gpr(vcpu, rt, vcpu->arch.srr1); break;
+                                kvmppc_set_gpr(vcpu, rt, vcpu->arch.shared->srr1);
+                                break;
                         case SPRN_PVR:
                                 kvmppc_set_gpr(vcpu, rt, vcpu->arch.pvr); break;
                         case SPRN_PIR:
@@ -320,9 +322,11 @@ int kvmppc_emulate_instruction(struct kvm_run *run, struct kvm_vcpu *vcpu)
                         rs = get_rs(inst);
                         switch (sprn) {
                         case SPRN_SRR0:
-                                vcpu->arch.srr0 = kvmppc_get_gpr(vcpu, rs); break;
+                                vcpu->arch.shared->srr0 = kvmppc_get_gpr(vcpu, rs);
+                                break;
                         case SPRN_SRR1:
-                                vcpu->arch.srr1 = kvmppc_get_gpr(vcpu, rs); break;
+                                vcpu->arch.shared->srr1 = kvmppc_get_gpr(vcpu, rs);
+                                break;
 
                         /* XXX We need to context-switch the timebase for
                          * watchdog and FIT. */