1 files changed, 31 insertions, 0 deletions

diff --git a/arch/powerpc/kvm/booke.h b/arch/powerpc/kvm/booke.h
index d53bcf2558f5..62c4fe55d19b 100644
--- a/arch/powerpc/kvm/booke.h
+++ b/arch/powerpc/kvm/booke.h
@@ -23,6 +23,7 @@
 #include <linux/types.h>
 #include <linux/kvm_host.h>
 #include <asm/kvm_ppc.h>
+#include <asm/switch_to.h>
 #include "timing.h"
 
 /* interrupt priortity ordering */
@@ -96,4 +97,34 @@ enum int_class {
 
 void kvmppc_set_pending_interrupt(struct kvm_vcpu *vcpu, enum int_class type);
 
+/*
+ * Load up guest vcpu FP state if it's needed.
+ * It also set the MSR_FP in thread so that host know
+ * we're holding FPU, and then host can help to save
+ * guest vcpu FP state if other threads require to use FPU.
+ * This simulates an FP unavailable fault.
+ *
+ * It requires to be called with preemption disabled.
+ */
+static inline void kvmppc_load_guest_fp(struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_PPC_FPU
+        if (vcpu->fpu_active && !(current->thread.regs->msr & MSR_FP)) {
+                load_up_fpu();
+                current->thread.regs->msr |= MSR_FP;
+        }
+#endif
+}
+
+/*
+ * Save guest vcpu FP state into thread.
+ * It requires to be called with preemption disabled.
+ */
+static inline void kvmppc_save_guest_fp(struct kvm_vcpu *vcpu)
+{
+#ifdef CONFIG_PPC_FPU
+        if (vcpu->fpu_active && (current->thread.regs->msr & MSR_FP))
+                giveup_fpu(current);
+#endif
+}
 #endif /* __KVM_BOOKE_H__ */