kvm: Decouple 'GSI routing' from 'kernel irqchip'

Don't assume having an in-kernel irqchip means that GSI
routing is enabled.

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

kvm-all.c

@@ -103,6 +103,7 @@ bool kvm_kernel_irqchip;
 bool kvm_async_interrupts_allowed;
 bool kvm_irqfds_allowed;
 bool kvm_msi_via_irqfd_allowed;
+bool kvm_gsi_routing_allowed;
 
 static const KVMCapabilityInfo kvm_required_capabilites[] = {
     KVM_CAP_INFO(USER_MEMORY),
@@ -1099,7 +1100,7 @@ int kvm_irqchip_add_msi_route(KVMState *s, MSIMessage msg)
     struct kvm_irq_routing_entry kroute;
     int virq;
 
-    if (!kvm_irqchip_in_kernel()) {
+    if (!kvm_gsi_routing_enabled()) {
         return -ENOSYS;
     }
 

kvm-stub.c

@@ -22,6 +22,7 @@ bool kvm_kernel_irqchip;
 bool kvm_async_interrupts_allowed;
 bool kvm_irqfds_allowed;
 bool kvm_msi_via_irqfd_allowed;
+bool kvm_gsi_routing_allowed;
 
 int kvm_init_vcpu(CPUArchState *env)
 {

kvm.h

@@ -27,6 +27,7 @@ extern bool kvm_kernel_irqchip;
 extern bool kvm_async_interrupts_allowed;
 extern bool kvm_irqfds_allowed;
 extern bool kvm_msi_via_irqfd_allowed;
+extern bool kvm_gsi_routing_allowed;
 
 #if defined CONFIG_KVM || !defined NEED_CPU_H
 #define kvm_enabled()           (kvm_allowed)
@@ -60,12 +61,21 @@ extern bool kvm_msi_via_irqfd_allowed;
  */
 #define kvm_msi_via_irqfd_enabled() (kvm_msi_via_irqfd_allowed)
 
+/**
+ * kvm_gsi_routing_enabled:
+ *
+ * Returns: true if GSI routing is enabled (ie the kernel supports
+ * it and we're running in a configuration that permits it).
+ */
+#define kvm_gsi_routing_enabled() (kvm_gsi_routing_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)
+#define kvm_gsi_routing_allowed() (false)
 #endif
 
 struct kvm_run;

target-i386/kvm.c

@@ -2049,8 +2049,9 @@ void kvm_arch_init_irq_routing(KVMState *s)
     }
     /* We know at this point that we're using the in-kernel
      * irqchip, so we can use irqfds, and on x86 we know
-     * we can use msi via irqfd.
+     * we can use msi via irqfd and GSI routing.
      */
     kvm_irqfds_allowed = true;
     kvm_msi_via_irqfd_allowed = true;
+    kvm_gsi_routing_allowed = true;
 }