kvm: powerpc: book3s: Add is_hv_enabled to kvmppc_ops

This help us to identify whether we are running with hypervisor mode KVM
enabled. The change is needed so that we can have both HV and PR kvm
enabled in the same kernel.

If both HV and PR KVM are included, interrupts come in to the HV version
of the kvmppc_interrupt code, which then jumps to the PR handler,
renamed to kvmppc_interrupt_pr, if the guest is a PR guest.

Allowing both PR and HV in the same kernel required some changes to
kvm_dev_ioctl_check_extension(), since the values returned now can't
be selected with #ifdefs as much as previously. We look at is_hv_enabled
to return the right value when checking for capabilities.For capabilities that
are only provided by HV KVM, we return the HV value only if
is_hv_enabled is true. For capabilities provided by PR KVM but not HV,
we return the PR value only if is_hv_enabled is false.

NOTE: in later patch we replace is_hv_enabled with a static inline
function comparing kvm_ppc_ops

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index 326033c..c13f15d 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -180,6 +180,7 @@
 };
 
 struct kvmppc_ops {
+	bool is_hv_enabled;
 	int (*get_sregs)(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs);
 	int (*set_sregs)(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs);
 	int (*get_one_reg)(struct kvm_vcpu *vcpu, u64 id,
@@ -309,10 +310,10 @@
 
 static inline u32 kvmppc_get_xics_latch(void)
 {
-	u32 xirr = get_paca()->kvm_hstate.saved_xirr;
+	u32 xirr;
 
+	xirr = get_paca()->kvm_hstate.saved_xirr;
 	get_paca()->kvm_hstate.saved_xirr = 0;
-
 	return xirr;
 }