kvm: remove hard dependency on pci

The msi routing code in kvm calls some pci functions: provide
some stubs to enable builds without pci.

Also, to make this more obvious, guard them via a pci_available boolean
(which also can be reused in other places).

Fixes: e1d4fb2de ("kvm-irqchip: x86: add msi route notify fn")
Fixes: 767a554a0 ("kvm-all: Pass requester ID to MSI routing functions")
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

accel/kvm/kvm-all.c

@@ -1248,7 +1248,7 @@ int kvm_irqchip_add_msi_route(KVMState *s, int vector, PCIDevice *dev)
     int virq;
     MSIMessage msg = {0, 0};
 
-    if (dev) {
+    if (pci_available && dev) {
         msg = pci_get_msi_message(dev, vector);
     }
 
@@ -1271,7 +1271,7 @@ int kvm_irqchip_add_msi_route(KVMState *s, int vector, PCIDevice *dev)
     kroute.u.msi.address_lo = (uint32_t)msg.address;
     kroute.u.msi.address_hi = msg.address >> 32;
     kroute.u.msi.data = le32_to_cpu(msg.data);
-    if (kvm_msi_devid_required()) {
+    if (pci_available && kvm_msi_devid_required()) {
         kroute.flags = KVM_MSI_VALID_DEVID;
         kroute.u.msi.devid = pci_requester_id(dev);
     }
@@ -1309,7 +1309,7 @@ int kvm_irqchip_update_msi_route(KVMState *s, int virq, MSIMessage msg,
     kroute.u.msi.address_lo = (uint32_t)msg.address;
     kroute.u.msi.address_hi = msg.address >> 32;
     kroute.u.msi.data = le32_to_cpu(msg.data);
-    if (kvm_msi_devid_required()) {
+    if (pci_available && kvm_msi_devid_required()) {
         kroute.flags = KVM_MSI_VALID_DEVID;
         kroute.u.msi.devid = pci_requester_id(dev);
     }

hw/pci/pci-stub.c

@@ -27,6 +27,7 @@
 #include "hw/pci/msi.h"
 
 bool msi_nonbroken;
+bool pci_available;
 
 PciInfoList *qmp_query_pci(Error **errp)
 {
@@ -38,3 +39,16 @@ void hmp_pcie_aer_inject_error(Monitor *mon, const QDict *qdict)
 {
     monitor_printf(mon, "PCI devices not supported\n");
 }
+
+/* kvm-all wants this */
+MSIMessage pci_get_msi_message(PCIDevice *dev, int vector)
+{
+    g_assert(false);
+    return (MSIMessage){};
+}
+
+uint16_t pci_requester_id(PCIDevice *dev)
+{
+    g_assert(false);
+    return 0;
+}

hw/pci/pci.c

@@ -49,6 +49,8 @@
 # define PCI_DPRINTF(format, ...)       do { } while (0)
 #endif
 
+bool pci_available = true;
+
 static void pcibus_dev_print(Monitor *mon, DeviceState *dev, int indent);
 static char *pcibus_get_dev_path(DeviceState *dev);
 static char *pcibus_get_fw_dev_path(DeviceState *dev);

include/hw/pci/pci.h

@@ -10,6 +10,8 @@
 
 #include "hw/pci/pcie.h"
 
+extern bool pci_available;
+
 /* PCI bus */
 
 #define PCI_DEVFN(slot, func)   ((((slot) & 0x1f) << 3) | ((func) & 0x07))