[PATCH 1/6] spapr: Add an "spapr" property to sPAPR CPU core

[Greg Kurz <groug@kaod.org>]

The sPAPR CPU core device can only work with pseries machine types.
This is currently checked in the realize function with a dynamic
cast of qdev_get_machine(). Some other places also need to reach
out to the machine using qdev_get_machine().

Make this dependency explicit by introducing an "spapr" link
property which officialy points to the machine. This link is
set by pseries machine types only in the pre-plug handler. This
allows to drop some users of qdev_get_machine().

Signed-off-by: Greg Kurz <groug@kaod.org>
---
 include/hw/ppc/spapr_cpu_core.h |  2 ++
 hw/ppc/spapr.c                  |  4 ++++
 hw/ppc/spapr_cpu_core.c         | 17 +++++++----------
 3 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/include/hw/ppc/spapr_cpu_core.h b/include/hw/ppc/spapr_cpu_core.h
index dab3dfc76c0a..0969b29fd96c 100644
--- a/include/hw/ppc/spapr_cpu_core.h
+++ b/include/hw/ppc/spapr_cpu_core.h
@@ -10,6 +10,7 @@
 #define HW_SPAPR_CPU_CORE_H
 
 #include "hw/cpu/core.h"
+#include "hw/ppc/spapr.h"
 #include "hw/qdev-core.h"
 #include "target/ppc/cpu-qom.h"
 #include "target/ppc/cpu.h"
@@ -24,6 +25,7 @@ OBJECT_DECLARE_TYPE(SpaprCpuCore, SpaprCpuCoreClass,
 struct SpaprCpuCore {
     /*< private >*/
     CPUCore parent_obj;
+    SpaprMachineState *spapr;
 
     /*< public >*/
     PowerPCCPU **threads;
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index d1dcf3ab2c94..4cc51723c62e 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -3816,6 +3816,10 @@ static void spapr_core_pre_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
     int index;
     unsigned int smp_threads = machine->smp.threads;
 
+    /* Required by spapr_cpu_core_realize() */
+    object_property_set_link(OBJECT(dev), "spapr", OBJECT(hotplug_dev),
+                             &error_abort);
+
     if (dev->hotplugged && !mc->has_hotpluggable_cpus) {
         error_setg(errp, "CPU hotplug not supported for this machine");
         return;
diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c
index 2f7dc3c23ded..dec09367e4a0 100644
--- a/hw/ppc/spapr_cpu_core.c
+++ b/hw/ppc/spapr_cpu_core.c
@@ -25,14 +25,13 @@
 #include "sysemu/hw_accel.h"
 #include "qemu/error-report.h"
 
-static void spapr_reset_vcpu(PowerPCCPU *cpu)
+static void spapr_reset_vcpu(PowerPCCPU *cpu, SpaprMachineState *spapr)
 {
     CPUState *cs = CPU(cpu);
     CPUPPCState *env = &cpu->env;
     PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
     SpaprCpuState *spapr_cpu = spapr_cpu_state(cpu);
     target_ulong lpcr;
-    SpaprMachineState *spapr = SPAPR_MACHINE(qdev_get_machine());
 
     cpu_reset(cs);
 
@@ -186,7 +185,7 @@ static void spapr_unrealize_vcpu(PowerPCCPU *cpu, SpaprCpuCore *sc)
     if (!sc->pre_3_0_migration) {
         vmstate_unregister(NULL, &vmstate_spapr_cpu_state, cpu->machine_data);
     }
-    spapr_irq_cpu_intc_destroy(SPAPR_MACHINE(qdev_get_machine()), cpu);
+    spapr_irq_cpu_intc_destroy(sc->spapr, cpu);
     qdev_unrealize(DEVICE(cpu));
 }
 
@@ -200,7 +199,7 @@ static void spapr_cpu_core_reset(DeviceState *dev)
     int i;
 
     for (i = 0; i < cc->nr_threads; i++) {
-        spapr_reset_vcpu(sc->threads[i]);
+        spapr_reset_vcpu(sc->threads[i], sc->spapr);
     }
 }
 
@@ -314,16 +313,12 @@ err:
 
 static void spapr_cpu_core_realize(DeviceState *dev, Error **errp)
 {
-    /* We don't use SPAPR_MACHINE() in order to exit gracefully if the user
-     * tries to add a sPAPR CPU core to a non-pseries machine.
-     */
-    SpaprMachineState *spapr =
-        (SpaprMachineState *) object_dynamic_cast(qdev_get_machine(),
-                                                  TYPE_SPAPR_MACHINE);
     SpaprCpuCore *sc = SPAPR_CPU_CORE(OBJECT(dev));
+    SpaprMachineState *spapr = sc->spapr;
     CPUCore *cc = CPU_CORE(OBJECT(dev));
     int i;
 
+    /* Set in spapr_core_pre_plug() */
     if (!spapr) {
         error_setg(errp, TYPE_SPAPR_CPU_CORE " needs a pseries machine");
         return;
@@ -345,6 +340,8 @@ static Property spapr_cpu_core_properties[] = {
     DEFINE_PROP_INT32("node-id", SpaprCpuCore, node_id, CPU_UNSET_NUMA_NODE_ID),
     DEFINE_PROP_BOOL("pre-3.0-migration", SpaprCpuCore, pre_3_0_migration,
                      false),
+    DEFINE_PROP_LINK("spapr", SpaprCpuCore, spapr, TYPE_SPAPR_MACHINE,
+                     SpaprMachineState *),
     DEFINE_PROP_END_OF_LIST()
 };
 
-- 
2.26.2