KVM: x86/xen: register shared_info page
[linux-2.6-microblaze.git] / arch / x86 / kvm / xen.c
index 55da739..924d4e8 100644 (file)
 #include <linux/kvm_host.h>
 
 #include <trace/events/kvm.h>
+#include <xen/interface/xen.h>
 
 #include "trace.h"
 
 DEFINE_STATIC_KEY_DEFERRED_FALSE(kvm_xen_enabled, HZ);
 
+static int kvm_xen_shared_info_init(struct kvm *kvm, gfn_t gfn)
+{
+       int ret;
+       int idx = srcu_read_lock(&kvm->srcu);
+
+       ret = kvm_gfn_to_hva_cache_init(kvm, &kvm->arch.xen.shinfo_cache,
+                                       gfn_to_gpa(gfn), PAGE_SIZE);
+       if (!ret) {
+               kvm->arch.xen.shinfo_set = true;
+       }
+
+       srcu_read_unlock(&kvm->srcu, idx);
+       return ret;
+}
+
 int kvm_xen_hvm_set_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data)
 {
        int r = -ENOENT;
 
+       mutex_lock(&kvm->lock);
+
        mutex_unlock(&kvm->lock);
 
        switch (data->type) {
        case KVM_XEN_ATTR_TYPE_LONG_MODE:
-               if (!IS_ENABLED(CONFIG_64BIT) && data->u.long_mode)
-                       return -EINVAL;
+               if (!IS_ENABLED(CONFIG_64BIT) && data->u.long_mode) {
+                       r = -EINVAL;
+               } else {
+                       kvm->arch.xen.long_mode = !!data->u.long_mode;
+                       r = 0;
+               }
+               break;
 
-               kvm->arch.xen.long_mode = !!data->u.long_mode;
-               r = 0;
+       case KVM_XEN_ATTR_TYPE_SHARED_INFO:
+               r = kvm_xen_shared_info_init(kvm, data->u.shared_info.gfn);
                break;
+
        default:
                break;
        }
@@ -51,6 +75,14 @@ int kvm_xen_hvm_get_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data)
                data->u.long_mode = kvm->arch.xen.long_mode;
                r = 0;
                break;
+
+       case KVM_XEN_ATTR_TYPE_SHARED_INFO:
+               if (kvm->arch.xen.shinfo_set) {
+                       data->u.shared_info.gfn = gpa_to_gfn(kvm->arch.xen.shinfo_cache.gpa);
+                       r = 0;
+               }
+               break;
+
        default:
                break;
        }