kvm: Introduce kvm_irqchip_add_msi_route

Add a service that establishes a static route from a virtual IRQ line to
an MSI message. Will be used for IRQFD and device assignment. As we will
use this service outside of CONFIG_KVM protected code, stub it properly.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAvi Kivity <avi@redhat.com>

kvm-all.c

@@ -1080,6 +1080,32 @@ int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg)
     return kvm_irqchip_set_irq(s, route->kroute.gsi, 1);
 }
 
+int kvm_irqchip_add_msi_route(KVMState *s, MSIMessage msg)
+{
+    struct kvm_irq_routing_entry kroute;
+    int virq;
+
+    if (!kvm_irqchip_in_kernel()) {
+        return -ENOSYS;
+    }
+
+    virq = kvm_irqchip_get_virq(s);
+    if (virq < 0) {
+        return virq;
+    }
+
+    kroute.gsi = virq;
+    kroute.type = KVM_IRQ_ROUTING_MSI;
+    kroute.flags = 0;
+    kroute.u.msi.address_lo = (uint32_t)msg.address;
+    kroute.u.msi.address_hi = msg.address >> 32;
+    kroute.u.msi.data = msg.data;
+
+    kvm_add_routing_entry(s, &kroute);
+
+    return virq;
+}
+
 #else /* !KVM_CAP_IRQ_ROUTING */
 
 static void kvm_init_irq_routing(KVMState *s)
@@ -1090,6 +1116,11 @@ int kvm_irqchip_send_msi(KVMState *s, MSIMessage msg)
 {
     abort();
 }
+
+int kvm_irqchip_add_msi_route(KVMState *s, MSIMessage msg)
+{
+    abort();
+}
 #endif /* !KVM_CAP_IRQ_ROUTING */
 
 static int kvm_irqchip_create(KVMState *s)

kvm-stub.c

@@ -12,10 +12,13 @@
 
 #include "qemu-common.h"
 #include "hw/hw.h"
+#include "hw/msi.h"
 #include "cpu.h"
 #include "gdbstub.h"
 #include "kvm.h"
 
+KVMState *kvm_state;
+
 int kvm_init_vcpu(CPUArchState *env)
 {
     return -ENOSYS;
@@ -128,3 +131,8 @@ int kvm_on_sigbus(int code, void *addr)
 {
     return 1;
 }
+
+int kvm_irqchip_add_msi_route(KVMState *s, MSIMessage msg)
+{
+    return -ENOSYS;
+}

kvm.h

@@ -44,6 +44,10 @@ typedef struct KVMCapabilityInfo {
 #define KVM_CAP_INFO(CAP) { "KVM_CAP_" stringify(CAP), KVM_CAP_##CAP }
 #define KVM_CAP_LAST_INFO { NULL, 0 }
 
+struct KVMState;
+typedef struct KVMState KVMState;
+extern KVMState *kvm_state;
+
 /* external API */
 
 int kvm_init(void);
@@ -88,10 +92,6 @@ int kvm_on_sigbus(int code, void *addr);
 
 /* internal API */
 
-struct KVMState;
-typedef struct KVMState KVMState;
-extern KVMState *kvm_state;
-
 int kvm_ioctl(KVMState *s, int type, ...);
 
 int kvm_vm_ioctl(KVMState *s, int type, ...);
@@ -213,4 +213,6 @@ int kvm_set_ioeventfd_mmio(int fd, uint32_t adr, uint32_t val, bool assign,
                            uint32_t size);
 
 int kvm_set_ioeventfd_pio_word(int fd, uint16_t adr, uint16_t val, bool assign);
+
+int kvm_irqchip_add_msi_route(KVMState *s, MSIMessage msg);
 #endif