pci: Add root bus argument to pci_get_bus_devfn()

pci_get_bus_devfn() interprets a full PCI address string to give a PCIBus *
and device/function number within that bus.  Currently it assumes it is
working on an address under the primary PCI root bus.  This patch extends
it to allow the caller to specify a root bus.  This might seem a little odd
since the supplied address can (theoretically) include a PCI domain number.
However, attempting to use a non-zero domain number there is currently an
error, so that shouldn't really cause problems.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 350b872294..c4f63ad9f3 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -589,12 +589,13 @@ int pci_parse_devaddr(const char *addr, int *domp, int *busp,
     return 0;
 }
 
-PCIBus *pci_get_bus_devfn(int *devfnp, const char *devaddr)
+PCIBus *pci_get_bus_devfn(int *devfnp, PCIBus *root, const char *devaddr)
 {
-    PCIBus *root = pci_find_primary_bus();
     int dom, bus;
     unsigned slot;
 
+    assert(!root->parent_dev);
+
     if (!root) {
         fprintf(stderr, "No primary PCI bus\n");
         return NULL;
@@ -1588,7 +1589,7 @@ PCIDevice *pci_nic_init(NICInfo *nd, const char *default_model,
     if (i < 0)
         return NULL;
 
-    bus = pci_get_bus_devfn(&devfn, devaddr);
+    bus = pci_get_bus_devfn(&devfn, pci_find_primary_bus(), devaddr);
     if (!bus) {
         error_report("Invalid PCI device address %s for device %s",
                      devaddr, pci_nic_names[i]);