KVM: PPC: Add mtsrin PV code

This is the guest side of the mtsr acceleration. Using this a guest can now
call mtsrin with almost no overhead as long as it ensures that it only uses
it with (MSR_IR|MSR_DR) == 0. Linux does that, so we're good.

Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 6d92b4e..7f0d6fc 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -478,6 +478,7 @@
 	DEFINE(KVM_MAGIC_MSR, offsetof(struct kvm_vcpu_arch_shared, msr));
 	DEFINE(KVM_MAGIC_CRITICAL, offsetof(struct kvm_vcpu_arch_shared,
 					    critical));
+	DEFINE(KVM_MAGIC_SR, offsetof(struct kvm_vcpu_arch_shared, sr));
 #endif
 
 #ifdef CONFIG_44x