[Qemu-devel] [PATCH v10 07/10] pci: introduce function validation check during hotplug

[Cao jin]

From: Chen Fan <address@hidden>

PCI hotplug requires that function 0 is added last to close the
slot.  Since vfio-pci supporting AER, we require that the VM bus
contains the same set of devices as the host bus to support AER,
we can perform an AER validation test whenever the function 0 is
hot-added into VM.

Signed-off-by: Chen Fan <address@hidden>
Signed-off-by: Dou Liyang <address@hidden>
Signed-off-by: Cao jin <address@hidden>
---
 hw/pci/pci.c         | 29 +++++++++++++++++++++++++++++
 include/hw/pci/pci.h |  1 +
 2 files changed, 30 insertions(+)

diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 24fae16..26eaf4c 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -1942,6 +1942,20 @@ PCIDevice *pci_find_device(PCIBus *bus, int bus_num, 
uint8_t devfn)
     return bus->devices[devfn];
 }
 
+static void pci_function_is_valid(PCIBus *bus, PCIDevice *d, void *opaque)
+{
+    PCIDeviceClass *pc = PCI_DEVICE_GET_CLASS(d);
+    Error **errp = opaque;
+
+    if (*errp) {
+        return;
+    }
+
+    if (pc->is_valid_func) {
+        pc->is_valid_func(d, errp);
+    }
+}
+
 static void pci_qdev_realize(DeviceState *qdev, Error **errp)
 {
     PCIDevice *pci_dev = (PCIDevice *)qdev;
@@ -1984,6 +1998,21 @@ static void pci_qdev_realize(DeviceState *qdev, Error 
**errp)
         pci_qdev_unrealize(DEVICE(pci_dev), NULL);
         return;
     }
+
+    /*
+     *  Hot-added function number 0 indicates the closure of the slot, it is
+     *  time to check whether all functions under the same bus is valid.
+     */
+    if (DEVICE(pci_dev)->hotplugged &&
+        pci_get_function_0(pci_dev) == pci_dev) {
+        pci_for_each_device(bus, pci_bus_num(bus),
+                            pci_function_is_valid, &local_err);
+        if (local_err) {
+            error_propagate(errp, local_err);
+            pci_qdev_unrealize(DEVICE(pci_dev), NULL);
+            return;
+        }
+    }
 }
 
 static void pci_default_realize(PCIDevice *dev, Error **errp)
diff --git a/include/hw/pci/pci.h b/include/hw/pci/pci.h
index 772692f..678f305 100644
--- a/include/hw/pci/pci.h
+++ b/include/hw/pci/pci.h
@@ -205,6 +205,7 @@ typedef struct PCIDeviceClass {
 
     void (*realize)(PCIDevice *dev, Error **errp);
     int (*init)(PCIDevice *dev);/* TODO convert to realize() and remove */
+    void (*is_valid_func)(PCIDevice *dev, Error **errp);
     PCIUnregisterFunc *exit;
     PCIConfigReadFunc *config_read;
     PCIConfigWriteFunc *config_write;
-- 
1.8.3.1