KVM: nVMX: Refactor IO bitmap checks into helper function

commit e71237d3ff1abf9f3388337cfebf53b96df2020d upstream.

Checks against the IO bitmap are useful for both instruction emulation
and VM-exit reflection. Refactor the IO bitmap checks into a helper
function.

Signed-off-by: Oliver Upton <oupton@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 4dc886d07d2a430469ae15990a51bde634465020..9c2c845cf0c0fd6199ab210457026179e08c4c9e 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -4641,6 +4641,26 @@ static bool cs_ss_rpl_check(struct kvm_vcpu *vcpu)
                 (ss.selector & SEGMENT_RPL_MASK));
 }
 
+static bool nested_vmx_check_io_bitmaps(struct kvm_vcpu *vcpu,
+                                       unsigned int port, int size);
+static bool nested_vmx_exit_handled_io(struct kvm_vcpu *vcpu,
+                                      struct vmcs12 *vmcs12)
+{
+       unsigned long exit_qualification;
+       unsigned int port;
+       int size;
+
+       if (!nested_cpu_has(vmcs12, CPU_BASED_USE_IO_BITMAPS))
+               return nested_cpu_has(vmcs12, CPU_BASED_UNCOND_IO_EXITING);
+
+       exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
+
+       port = exit_qualification >> 16;
+       size = (exit_qualification & 7) + 1;
+
+       return nested_vmx_check_io_bitmaps(vcpu, port, size);
+}
+
 /*
  * Check if guest state is valid. Returns true if valid, false if
  * not.
@@ -8026,23 +8046,17 @@ static int (*const kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = {
 static const int kvm_vmx_max_exit_handlers =
        ARRAY_SIZE(kvm_vmx_exit_handlers);
 
-static bool nested_vmx_exit_handled_io(struct kvm_vcpu *vcpu,
-                                      struct vmcs12 *vmcs12)
+/*
+ * Return true if an IO instruction with the specified port and size should cause
+ * a VM-exit into L1.
+ */
+bool nested_vmx_check_io_bitmaps(struct kvm_vcpu *vcpu, unsigned int port,
+                                int size)
 {
-       unsigned long exit_qualification;
+       struct vmcs12 *vmcs12 = get_vmcs12(vcpu);
        gpa_t bitmap, last_bitmap;
-       unsigned int port;
-       int size;
        u8 b;
 
-       if (!nested_cpu_has(vmcs12, CPU_BASED_USE_IO_BITMAPS))
-               return nested_cpu_has(vmcs12, CPU_BASED_UNCOND_IO_EXITING);
-
-       exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
-
-       port = exit_qualification >> 16;
-       size = (exit_qualification & 7) + 1;
-
        last_bitmap = (gpa_t)-1;
        b = -1;