Re: [Qemu-devel] [PATCH 3/5] PXB: convert to realize()

[Cao jin]

Hi,

On 12/20/2015 06:22 PM, Marcel Apfelbaum wrote:

Hi,

On 12/18/2015 01:03 PM, Cao jin wrote:
Signed-off-by: Cao jin <caoj.f...@cn.fujitsu.com>
---
  hw/pci-bridge/pci_expander_bridge.c | 24 ++++++++++++++----------
  1 file changed, 14 insertions(+), 10 deletions(-)

diff --git a/hw/pci-bridge/pci_expander_bridge.c
b/hw/pci-bridge/pci_expander_bridge.c
index 57f8a37..cc975f6 100644
--- a/hw/pci-bridge/pci_expander_bridge.c
+++ b/hw/pci-bridge/pci_expander_bridge.c
@@ -145,19 +145,19 @@ static const TypeInfo pxb_host_info = {
   * Returns 0 on successs, -1 if i440fx host was not
   * found or the bus number is already in use.
   */
-static int pxb_register_bus(PCIDevice *dev, PCIBus *pxb_bus)
+static int pxb_register_bus(PCIDevice *dev, PCIBus *pxb_bus, Error
**errp)

If you add an err parameter, maybe the function should return void.


Ok, will modify it in V2. Actually, both style are fine with me:)


  {
      PCIBus *bus = dev->bus;
      int pxb_bus_num = pci_bus_num(pxb_bus);

      if (bus->parent_dev) {
-        error_report("PXB devices can be attached only to root bus.");
+        error_setg(errp, "PXB devices can be attached only to root
bus.");
          return -1;
      }

      QLIST_FOREACH(bus, &bus->child, sibling) {
          if (pci_bus_num(bus) == pxb_bus_num) {
-            error_report("Bus %d is already in use.", pxb_bus_num);
+            error_setg(errp, "Bus %d is already in use.", pxb_bus_num);
              return -1;
          }
      }
@@ -193,7 +193,7 @@ static gint pxb_compare(gconstpointer a,
gconstpointer b)
             0;
  }

-static int pxb_dev_initfn(PCIDevice *dev)
+static void pxb_dev_realize(PCIDevice *dev, Error **errp)
  {
      PXBDev *pxb = PXB_DEV(dev);
      DeviceState *ds, *bds;
@@ -202,8 +202,8 @@ static int pxb_dev_initfn(PCIDevice *dev)

      if (pxb->numa_node != NUMA_NODE_UNASSIGNED &&
          pxb->numa_node >= nb_numa_nodes) {
-        error_report("Illegal numa node %d.", pxb->numa_node);
-        return -EINVAL;
+        error_setg(errp, "Illegal numa node %d.", pxb->numa_node);
+        return;
      }

      if (dev->qdev.id && *dev->qdev.id) {
@@ -225,8 +225,8 @@ static int pxb_dev_initfn(PCIDevice *dev)

      PCI_HOST_BRIDGE(ds)->bus = bus;

-    if (pxb_register_bus(dev, bus)) {
-        return -EINVAL;
+    if (pxb_register_bus(dev, bus, errp)) {
+        goto err_register_bus;
      }

      qdev_init_nofail(ds);
@@ -237,7 +237,11 @@ static int pxb_dev_initfn(PCIDevice *dev)
      pci_config_set_class(dev->config, PCI_CLASS_BRIDGE_HOST);

      pxb_dev_list = g_list_insert_sorted(pxb_dev_list, pxb,
pxb_compare);
-    return 0;
+
+err_register_bus:
+    object_unref(OBJECT(ds));
+    object_unref(OBJECT(bds));
+    object_unref(OBJECT(bus));


The order should be in the reverse order of creation:
     bds, bus, ds


Ok, I can do that. But it seems the order here doesn`t matter? Is there 
dependency among these three?


  }

  static void pxb_dev_exitfn(PCIDevice *pci_dev)
@@ -259,7 +263,7 @@ static void pxb_dev_class_init(ObjectClass *klass,
void *data)
      DeviceClass *dc = DEVICE_CLASS(klass);
      PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);

-    k->init = pxb_dev_initfn;
+    k->realize = pxb_dev_realize;
      k->exit = pxb_dev_exitfn;

If init is converted to realize, maybe the exit should be converted to
unrealize?


Yup, I agree with you from the point that the names should be antonym. 
But it seems there is no PCIDeviceClass.unrealize:(

And I am also not aware why there is no comment for .exit while there is 
for .init. It is appreciated if somebody could tell me the history O:-)


Thanks,
Marcel

      k->vendor_id = PCI_VENDOR_ID_REDHAT;
      k->device_id = PCI_DEVICE_ID_REDHAT_PXB;




.


--
Yours Sincerely,

Cao Jin