KVM: MIPS: Add hardware_{enable,disable} callback

Add an implementation callback for the kvm_arch_hardware_enable() and
kvm_arch_hardware_disable() architecture functions, with simple stubs
for trap & emulate. This is in preparation for VZ which will make use of
them.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org

arch/mips/include/asm/kvm_host.h

@@ -542,6 +542,8 @@ struct kvm_mips_callbacks {
 	int (*handle_msa_fpe)(struct kvm_vcpu *vcpu);
 	int (*handle_fpe)(struct kvm_vcpu *vcpu);
 	int (*handle_msa_disabled)(struct kvm_vcpu *vcpu);
+	int (*hardware_enable)(void);
+	void (*hardware_disable)(void);
 	int (*check_extension)(struct kvm *kvm, long ext);
 	int (*vcpu_init)(struct kvm_vcpu *vcpu);
 	void (*vcpu_uninit)(struct kvm_vcpu *vcpu);
@@ -864,7 +866,6 @@ extern int kvm_mips_trans_mtc0(union mips_instruction inst, u32 *opc,
 extern void kvm_mips_dump_stats(struct kvm_vcpu *vcpu);
 extern unsigned long kvm_mips_get_ramsize(struct kvm *kvm);
 
-static inline void kvm_arch_hardware_disable(void) {}
 static inline void kvm_arch_hardware_unsetup(void) {}
 static inline void kvm_arch_sync_events(struct kvm *kvm) {}
 static inline void kvm_arch_free_memslot(struct kvm *kvm,

arch/mips/kvm/mips.c

@@ -92,7 +92,12 @@ int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
 
 int kvm_arch_hardware_enable(void)
 {
-	return 0;
+	return kvm_mips_callbacks->hardware_enable();
+}
+
+void kvm_arch_hardware_disable(void)
+{
+	kvm_mips_callbacks->hardware_disable();
 }
 
 int kvm_arch_hardware_setup(void)

arch/mips/kvm/trap_emul.c

@@ -488,6 +488,15 @@ static int kvm_trap_emul_handle_msa_disabled(struct kvm_vcpu *vcpu)
 	return ret;
 }
 
+static int kvm_trap_emul_hardware_enable(void)
+{
+	return 0;
+}
+
+static void kvm_trap_emul_hardware_disable(void)
+{
+}
+
 static int kvm_trap_emul_check_extension(struct kvm *kvm, long ext)
 {
 	int r;
@@ -1254,6 +1263,8 @@ static struct kvm_mips_callbacks kvm_trap_emul_callbacks = {
 	.handle_fpe = kvm_trap_emul_handle_fpe,
 	.handle_msa_disabled = kvm_trap_emul_handle_msa_disabled,
 
+	.hardware_enable = kvm_trap_emul_hardware_enable,
+	.hardware_disable = kvm_trap_emul_hardware_disable,
 	.check_extension = kvm_trap_emul_check_extension,
 	.vcpu_init = kvm_trap_emul_vcpu_init,
 	.vcpu_uninit = kvm_trap_emul_vcpu_uninit,