[Qemu-devel] [PATCH RFC 09/10] pc: Support for PCI based memory devices

[David Hildenbrand]

Override the PCI device hotplug handler to properly handle the
memory device part from the machine hotplug handler and forward to the
actual PCI bus hotplug handler.

As PCI hotplug has not been properly factored out into hotplug handlers,
most magic is performed in the (un)realize functions. Also some buses don't
have a PCI hotplug handler at all yet (not sure if they are actually used
on x86, but just to be sure).

Signed-off-by: David Hildenbrand <address@hidden>
---
 hw/i386/pc.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 89 insertions(+), 1 deletion(-)

diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index fd0cb29ba9..62f83859fa 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -75,6 +75,7 @@
 #include "hw/usb.h"
 #include "hw/i386/intel_iommu.h"
 #include "hw/net/ne2000-isa.h"
+#include "hw/mem/memory-device.h"
 
 /* debug PC/ISA interrupts */
 //#define DEBUG_IRQ
@@ -2224,6 +2225,84 @@ static void pc_cpu_pre_plug(HotplugHandler *hotplug_dev,
     numa_cpu_pre_plug(cpu_slot, dev, errp);
 }
 
+static void pc_pci_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
+                            Error **errp)
+{
+    HotplugHandler *hotplug_dev2 = qdev_get_bus_hotplug_handler(dev);
+    Error *local_err = NULL;
+
+    if (object_dynamic_cast(OBJECT(dev), TYPE_MEMORY_DEVICE)) {
+        if (!hotplug_dev2) {
+            /*
+             * Without a bus hotplug handler, we cannot control the plug/unplug
+             * order. Disallow memory devices on such buses.
+             */
+            error_setg(errp, "Memory devices not supported on this bus.");
+            return;
+        }
+        memory_device_pre_plug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev),
+                               NULL, errp);
+    }
+
+    if (hotplug_dev2) {
+        hotplug_handler_pre_plug(hotplug_dev2, dev, errp);
+        if (local_err) {
+            error_propagate(errp, local_err);
+            return;
+        }
+    }
+}
+
+static void pc_pci_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
+                        Error **errp)
+{
+    HotplugHandler *hotplug_dev2 = qdev_get_bus_hotplug_handler(dev);
+    Error *local_err = NULL;
+
+    if (object_dynamic_cast(OBJECT(dev), TYPE_MEMORY_DEVICE)) {
+        memory_device_plug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev));
+    }
+
+    if (hotplug_dev2) {
+        hotplug_handler_plug(hotplug_dev2, dev, &local_err);
+    }
+
+    if (local_err) {
+        if (object_dynamic_cast(OBJECT(dev), TYPE_MEMORY_DEVICE)) {
+            memory_device_unplug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev));
+        }
+    }
+    error_propagate(errp, local_err);
+}
+
+static void pc_pci_unplug_request(HotplugHandler *hotplug_dev, DeviceState 
*dev,
+                                  Error **errp)
+{
+    HotplugHandler *hotplug_dev2 = qdev_get_bus_hotplug_handler(dev);
+
+    if (hotplug_dev2) {
+        hotplug_handler_unplug_request(hotplug_dev2, dev, errp);
+    }
+}
+
+static void pc_pci_device_unplug(HotplugHandler *hotplug_dev, DeviceState *dev,
+                                 Error **errp)
+{
+    HotplugHandler *hotplug_dev2 = qdev_get_bus_hotplug_handler(dev);
+    Error *local_err = NULL;
+
+    if (hotplug_dev2) {
+        hotplug_handler_unplug(hotplug_dev2, dev, &local_err);
+    }
+
+    if (!local_err) {
+        if (object_dynamic_cast(OBJECT(dev), TYPE_MEMORY_DEVICE)) {
+            memory_device_unplug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev));
+        }
+    }
+    error_propagate(errp, local_err);
+}
+
 static void pc_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev,
                                           DeviceState *dev, Error **errp)
 {
@@ -2231,6 +2310,8 @@ static void pc_machine_device_pre_plug_cb(HotplugHandler 
*hotplug_dev,
         pc_memory_pre_plug(hotplug_dev, dev, errp);
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
         pc_cpu_pre_plug(hotplug_dev, dev, errp);
+    } else if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
+        pc_pci_pre_plug(hotplug_dev, dev, errp);
     }
 }
 
@@ -2241,6 +2322,8 @@ static void pc_machine_device_plug_cb(HotplugHandler 
*hotplug_dev,
         pc_memory_plug(hotplug_dev, dev, errp);
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
         pc_cpu_plug(hotplug_dev, dev, errp);
+    } else if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
+        pc_pci_plug(hotplug_dev, dev, errp);
     }
 }
 
@@ -2251,6 +2334,8 @@ static void 
pc_machine_device_unplug_request_cb(HotplugHandler *hotplug_dev,
         pc_memory_unplug_request(hotplug_dev, dev, errp);
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
         pc_cpu_unplug_request_cb(hotplug_dev, dev, errp);
+    } else if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
+        pc_pci_unplug_request(hotplug_dev, dev, errp);
     } else {
         error_setg(errp, "acpi: device unplug request for not supported device"
                    " type: %s", object_get_typename(OBJECT(dev)));
@@ -2264,6 +2349,8 @@ static void pc_machine_device_unplug_cb(HotplugHandler 
*hotplug_dev,
         pc_memory_unplug(hotplug_dev, dev, errp);
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
         pc_cpu_unplug_cb(hotplug_dev, dev, errp);
+    } else if (object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
+        pc_pci_device_unplug(hotplug_dev, dev, errp);
     } else {
         error_setg(errp, "acpi: device unplug for not supported device"
                    " type: %s", object_get_typename(OBJECT(dev)));
@@ -2274,7 +2361,8 @@ static HotplugHandler *pc_get_hotpug_handler(MachineState 
*machine,
                                              DeviceState *dev)
 {
     if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM) ||
-        object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
+        object_dynamic_cast(OBJECT(dev), TYPE_CPU) ||
+        object_dynamic_cast(OBJECT(dev), TYPE_PCI_DEVICE)) {
         return HOTPLUG_HANDLER(machine);
     }
 
-- 
2.17.2