[Qemu-devel] [PATCH v5 1/2] remove function during multi-function hot-add

[Cao jin]

In case user regret when hot-add multi-function, we should roll back,
device_del the function added but still not worked.

Signed-off-by: Cao jin <address@hidden>
---
 hw/pci/pcie.c | 23 ++++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
index 6e28985..b1adeaf 100644
--- a/hw/pci/pcie.c
+++ b/hw/pci/pcie.c
@@ -261,13 +261,31 @@ void pcie_cap_slot_hotplug_cb(HotplugHandler 
*hotplug_dev, DeviceState *dev,
                         PCI_EXP_HP_EV_PDC | PCI_EXP_HP_EV_ABP);
 }
 
+static void pcie_unplug_device(PCIBus *bus, PCIDevice *dev, void *opaque)
+{
+    object_unparent(OBJECT(dev));
+}
+
 void pcie_cap_slot_hot_unplug_request_cb(HotplugHandler *hotplug_dev,
                                          DeviceState *dev, Error **errp)
 {
     uint8_t *exp_cap;
+    PCIDevice *pci_dev = PCI_DEVICE(dev);
+    PCIBus *bus = pci_dev->bus;
 
     pcie_cap_slot_hotplug_common(PCI_DEVICE(hotplug_dev), dev, &exp_cap, errp);
 
+    /* In case user cancel the operation of multi-function hot-add,
+     * remove the function that is unexposed to guest individually,
+     * without interaction with guest.
+     */
+    if (PCI_FUNC(pci_dev->devfn) &&
+        !bus->devices[PCI_DEVFN(PCI_SLOT(pci_dev->devfn), 0)]) {
+        pcie_unplug_device(bus, pci_dev, NULL);
+
+        return;
+    }
+
     pcie_cap_slot_push_attention_button(PCI_DEVICE(hotplug_dev));
 }
 
@@ -378,11 +396,6 @@ void pcie_cap_slot_reset(PCIDevice *dev)
     hotplug_event_update_event_status(dev);
 }
 
-static void pcie_unplug_device(PCIBus *bus, PCIDevice *dev, void *opaque)
-{
-    object_unparent(OBJECT(dev));
-}
-
 void pcie_cap_slot_write_config(PCIDevice *dev,
                                 uint32_t addr, uint32_t val, int len)
 {
-- 
2.1.0