KVM: xen: do not use struct gfn_to_hva_cache

gfn_to_hva_cache is not thread-safe, so it is usually used only within
a vCPU (whose code is protected by vcpu->mutex).  The Xen interface
implementation has such a cache in kvm->arch, but it is not really
used except to store the location of the shared info page.  Replace
shinfo_set and shinfo_cache with just the value that is passed via
KVM_XEN_ATTR_TYPE_SHARED_INFO; the only complication is that the
initialization value is not zero anymore and therefore kvm_xen_init_vm
needs to be introduced.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/arch/x86/kvm/xen.h b/arch/x86/kvm/xen.h
index 463a7844a8ca..cc0cf5f37450 100644
--- a/arch/x86/kvm/xen.h
+++ b/arch/x86/kvm/xen.h
@@ -21,6 +21,7 @@ int kvm_xen_hvm_set_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data);
 int kvm_xen_hvm_get_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data);
 int kvm_xen_write_hypercall_page(struct kvm_vcpu *vcpu, u64 data);
 int kvm_xen_hvm_config(struct kvm *kvm, struct kvm_xen_hvm_config *xhc);
+void kvm_xen_init_vm(struct kvm *kvm);
 void kvm_xen_destroy_vm(struct kvm *kvm);
 
 static inline bool kvm_xen_msr_enabled(struct kvm *kvm)
@@ -50,6 +51,10 @@ static inline int kvm_xen_write_hypercall_page(struct kvm_vcpu *vcpu, u64 data)
 	return 1;
 }
 
+static inline void kvm_xen_init_vm(struct kvm *kvm)
+{
+}
+
 static inline void kvm_xen_destroy_vm(struct kvm *kvm)
 {
 }