kvm: Decouple 'MSI routing via irqfds' from 'kernel irqchip'

Decouple another x86-specific assumption about what irqchips imply.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/kvm.h b/kvm.h
index 21436ef5d..34d32c7cc 100644
--- a/kvm.h
+++ b/kvm.h
@@ -26,6 +26,7 @@ extern int kvm_allowed;
 extern bool kvm_kernel_irqchip;
 extern bool kvm_async_interrupts_allowed;
 extern bool kvm_irqfds_allowed;
+extern bool kvm_msi_via_irqfd_allowed;
 
 #if defined CONFIG_KVM || !defined NEED_CPU_H
 #define kvm_enabled()           (kvm_allowed)
@@ -50,11 +51,21 @@ extern bool kvm_irqfds_allowed;
  */
 #define kvm_irqfds_enabled() (kvm_irqfds_allowed)
 
+/**
+ * kvm_msi_via_irqfd_enabled:
+ *
+ * Returns: true if we can route a PCI MSI (Message Signaled Interrupt)
+ * to a KVM CPU via an irqfd. This requires that the kernel supports
+ * this and that we're running in a configuration that permits it.
+ */
+#define kvm_msi_via_irqfd_enabled() (kvm_msi_via_irqfd_allowed)
+
 #else
 #define kvm_enabled()           (0)
 #define kvm_irqchip_in_kernel() (false)
 #define kvm_async_interrupts_enabled() (false)
 #define kvm_irqfds_enabled() (false)
+#define kvm_msi_via_irqfd_enabled() (false)
 #endif
 
 struct kvm_run;