1 files changed, 72 insertions, 0 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 1453248723eb..f5c60a84fcf5 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4136,6 +4136,78 @@ int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa,
         return 1;
 }
 
+struct read_write_emulator_ops {
+        int (*read_write_prepare)(struct kvm_vcpu *vcpu, void *val,
+                                  int bytes);
+        int (*read_write_emulate)(struct kvm_vcpu *vcpu, gpa_t gpa,
+                                  void *val, int bytes);
+        int (*read_write_mmio)(struct kvm_vcpu *vcpu, gpa_t gpa,
+                               int bytes, void *val);
+        int (*read_write_exit_mmio)(struct kvm_vcpu *vcpu, gpa_t gpa,
+                                    void *val, int bytes);
+        bool write;
+};
+
+static int read_prepare(struct kvm_vcpu *vcpu, void *val, int bytes)
+{
+        if (vcpu->mmio_read_completed) {
+                memcpy(val, vcpu->mmio_data, bytes);
+                trace_kvm_mmio(KVM_TRACE_MMIO_READ, bytes,
+                               vcpu->mmio_phys_addr, *(u64 *)val);
+                vcpu->mmio_read_completed = 0;
+                return 1;
+        }
+
+        return 0;
+}
+
+static int read_emulate(struct kvm_vcpu *vcpu, gpa_t gpa,
+                        void *val, int bytes)
+{
+        return !kvm_read_guest(vcpu->kvm, gpa, val, bytes);
+}
+
+static int write_emulate(struct kvm_vcpu *vcpu, gpa_t gpa,
+                         void *val, int bytes)
+{
+        return emulator_write_phys(vcpu, gpa, val, bytes);
+}
+
+static int write_mmio(struct kvm_vcpu *vcpu, gpa_t gpa, int bytes, void *val)
+{
+        trace_kvm_mmio(KVM_TRACE_MMIO_WRITE, bytes, gpa, *(u64 *)val);
+        return vcpu_mmio_write(vcpu, gpa, bytes, val);
+}
+
+static int read_exit_mmio(struct kvm_vcpu *vcpu, gpa_t gpa,
+                          void *val, int bytes)
+{
+        trace_kvm_mmio(KVM_TRACE_MMIO_READ_UNSATISFIED, bytes, gpa, 0);
+        return X86EMUL_IO_NEEDED;
+}
+
+static int write_exit_mmio(struct kvm_vcpu *vcpu, gpa_t gpa,
+                           void *val, int bytes)
+{
+        memcpy(vcpu->mmio_data, val, bytes);
+        memcpy(vcpu->run->mmio.data, vcpu->mmio_data, 8);
+        return X86EMUL_CONTINUE;
+}
+
+static struct read_write_emulator_ops read_emultor = {
+        .read_write_prepare = read_prepare,
+        .read_write_emulate = read_emulate,
+        .read_write_mmio = vcpu_mmio_read,
+        .read_write_exit_mmio = read_exit_mmio,
+};
+
+static struct read_write_emulator_ops write_emultor = {
+        .read_write_emulate = write_emulate,
+        .read_write_mmio = write_mmio,
+        .read_write_exit_mmio = write_exit_mmio,
+        .write = true,
+};
+
 static int emulator_write_emulated_onepage(unsigned long addr,
                                            const void *val,
                                            unsigned int bytes,