KVM: MIPS: let generic code call prepare_flush_shadow

Since all calls to kvm_flush_remote_tlbs must be preceded by
kvm_mips_callbacks->prepare_flush_shadow, repurpose
kvm_arch_flush_remote_tlb to invoke it.  This makes it possible
to use the TLB flushing mechanism provided by the generic MMU
notifier code.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/mips/include/asm/kvm_host.h

@@ -1142,4 +1142,7 @@ static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {}
 static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {}
 static inline void kvm_arch_vcpu_block_finish(struct kvm_vcpu *vcpu) {}
 
+#define __KVM_HAVE_ARCH_FLUSH_REMOTE_TLB
+int kvm_arch_flush_remote_tlb(struct kvm *kvm);
+
 #endif /* __MIPS_KVM_HOST_H__ */

arch/mips/kvm/mips.c

@@ -204,9 +204,6 @@ void kvm_arch_flush_shadow_all(struct kvm *kvm)
 {
 	/* Flush whole GPA */
 	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
-
-	/* Let implementation do the rest */
-	kvm_mips_callbacks->prepare_flush_shadow(kvm);
 	kvm_flush_remote_tlbs(kvm);
 }
 
@@ -995,11 +992,15 @@ void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
 
 }
 
+int kvm_arch_flush_remote_tlb(struct kvm *kvm)
+{
+	kvm_mips_callbacks->prepare_flush_shadow(kvm);
+	return 1;
+}
+
 void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
 					const struct kvm_memory_slot *memslot)
 {
-	/* Let implementation handle TLB/GVA invalidation */
-	kvm_mips_callbacks->prepare_flush_shadow(kvm);
 	kvm_flush_remote_tlbs(kvm);
 }
 

arch/mips/kvm/mmu.c

@@ -490,8 +490,6 @@ int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end,
 			unsigned flags)
 {
 	handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, NULL);
-
-	kvm_mips_callbacks->prepare_flush_shadow(kvm);
 	kvm_flush_remote_tlbs(kvm);
 	return 0;
 }
@@ -533,10 +531,8 @@ int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
 	int ret;
 
 	ret = handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &pte);
-	if (ret) {
-		kvm_mips_callbacks->prepare_flush_shadow(kvm);
+	if (ret)
 		kvm_flush_remote_tlbs(kvm);
-	}
 	return 0;
 }