[PATCH v2 1/4] migration: Define VMSTATE_INSTANCE_ID_ANY

[Peter Xu <peterx@redhat.com>]

Define the new macro VMSTATE_INSTANCE_ID_ANY for callers who wants to
auto-generate the vmstate instance ID.  Previously it was hard coded
as -1 instead of this macro.  It helps to change this default value in
the follow up patches.  No functional change.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 hw/arm/stellaris.c          | 2 +-
 hw/core/qdev.c              | 3 ++-
 hw/display/ads7846.c        | 2 +-
 hw/i2c/core.c               | 2 +-
 hw/input/stellaris_input.c  | 3 ++-
 hw/intc/apic_common.c       | 2 +-
 hw/misc/max111x.c           | 2 +-
 hw/net/eepro100.c           | 2 +-
 hw/pci/pci.c                | 2 +-
 hw/ppc/spapr.c              | 2 +-
 hw/timer/arm_timer.c        | 2 +-
 hw/tpm/tpm_emulator.c       | 3 ++-
 include/migration/vmstate.h | 2 ++
 migration/savevm.c          | 8 ++++----
 14 files changed, 21 insertions(+), 16 deletions(-)

diff --git a/hw/arm/stellaris.c b/hw/arm/stellaris.c
index b198066b54..bb025e0bd0 100644
--- a/hw/arm/stellaris.c
+++ b/hw/arm/stellaris.c
@@ -708,7 +708,7 @@ static int stellaris_sys_init(uint32_t base, qemu_irq irq,
     memory_region_init_io(&s->iomem, NULL, &ssys_ops, s, "ssys", 0x00001000);
     memory_region_add_subregion(get_system_memory(), base, &s->iomem);
     ssys_reset(s);
-    vmstate_register(NULL, -1, &vmstate_stellaris_sys, s);
+    vmstate_register(NULL, VMSTATE_INSTANCE_ID_ANY, &vmstate_stellaris_sys, s);
     return 0;
 }
 
diff --git a/hw/core/qdev.c b/hw/core/qdev.c
index cbad6c1d55..86031f961d 100644
--- a/hw/core/qdev.c
+++ b/hw/core/qdev.c
@@ -866,7 +866,8 @@ static void device_set_realized(Object *obj, bool value, Error **errp)
         dev->canonical_path = object_get_canonical_path(OBJECT(dev));
 
         if (qdev_get_vmsd(dev)) {
-            if (vmstate_register_with_alias_id(dev, -1, qdev_get_vmsd(dev), dev,
+            if (vmstate_register_with_alias_id(dev, VMSTATE_INSTANCE_ID_ANY,
+                                               qdev_get_vmsd(dev), dev,
                                                dev->instance_id_alias,
                                                dev->alias_required_for_version,
                                                &local_err) < 0) {
diff --git a/hw/display/ads7846.c b/hw/display/ads7846.c
index c12272ae72..9228b40b1a 100644
--- a/hw/display/ads7846.c
+++ b/hw/display/ads7846.c
@@ -154,7 +154,7 @@ static void ads7846_realize(SSISlave *d, Error **errp)
 
     ads7846_int_update(s);
 
-    vmstate_register(NULL, -1, &vmstate_ads7846, s);
+    vmstate_register(NULL, VMSTATE_INSTANCE_ID_ANY, &vmstate_ads7846, s);
 }
 
 static void ads7846_class_init(ObjectClass *klass, void *data)
diff --git a/hw/i2c/core.c b/hw/i2c/core.c
index 92cd489069..d770035ba0 100644
--- a/hw/i2c/core.c
+++ b/hw/i2c/core.c
@@ -61,7 +61,7 @@ I2CBus *i2c_init_bus(DeviceState *parent, const char *name)
 
     bus = I2C_BUS(qbus_create(TYPE_I2C_BUS, parent, name));
     QLIST_INIT(&bus->current_devs);
-    vmstate_register(NULL, -1, &vmstate_i2c_bus, bus);
+    vmstate_register(NULL, VMSTATE_INSTANCE_ID_ANY, &vmstate_i2c_bus, bus);
     return bus;
 }
 
diff --git a/hw/input/stellaris_input.c b/hw/input/stellaris_input.c
index 59892b07fc..e6ee5e11f1 100644
--- a/hw/input/stellaris_input.c
+++ b/hw/input/stellaris_input.c
@@ -88,5 +88,6 @@ void stellaris_gamepad_init(int n, qemu_irq *irq, const int *keycode)
     }
     s->num_buttons = n;
     qemu_add_kbd_event_handler(stellaris_gamepad_put_key, s);
-    vmstate_register(NULL, -1, &vmstate_stellaris_gamepad, s);
+    vmstate_register(NULL, VMSTATE_INSTANCE_ID_ANY,
+                     &vmstate_stellaris_gamepad, s);
 }
diff --git a/hw/intc/apic_common.c b/hw/intc/apic_common.c
index aafd8e0e33..22da53ce8a 100644
--- a/hw/intc/apic_common.c
+++ b/hw/intc/apic_common.c
@@ -331,7 +331,7 @@ static void apic_common_realize(DeviceState *dev, Error **errp)
     }
 
     if (s->legacy_instance_id) {
-        instance_id = -1;
+        instance_id = VMSTATE_INSTANCE_ID_ANY;
     }
     vmstate_register_with_alias_id(NULL, instance_id, &vmstate_apic_common,
                                    s, -1, 0, NULL);
diff --git a/hw/misc/max111x.c b/hw/misc/max111x.c
index a713149f16..81ee73e0da 100644
--- a/hw/misc/max111x.c
+++ b/hw/misc/max111x.c
@@ -146,7 +146,7 @@ static int max111x_init(SSISlave *d, int inputs)
     s->input[7] = 0x80;
     s->com = 0;
 
-    vmstate_register(dev, -1, &vmstate_max111x, s);
+    vmstate_register(dev, VMSTATE_INSTANCE_ID_ANY, &vmstate_max111x, s);
     return 0;
 }
 
diff --git a/hw/net/eepro100.c b/hw/net/eepro100.c
index cc2dd8b1c9..39920c6dc5 100644
--- a/hw/net/eepro100.c
+++ b/hw/net/eepro100.c
@@ -1874,7 +1874,7 @@ static void e100_nic_realize(PCIDevice *pci_dev, Error **errp)
 
     s->vmstate = g_memdup(&vmstate_eepro100, sizeof(vmstate_eepro100));
     s->vmstate->name = qemu_get_queue(s->nic)->model;
-    vmstate_register(&pci_dev->qdev, -1, s->vmstate, s);
+    vmstate_register(&pci_dev->qdev, VMSTATE_INSTANCE_ID_ANY, s->vmstate, s);
 }
 
 static void eepro100_instance_init(Object *obj)
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index aa05c2b9b2..708f66aac3 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -122,7 +122,7 @@ static void pci_bus_realize(BusState *qbus, Error **errp)
     bus->machine_done.notify = pcibus_machine_done;
     qemu_add_machine_init_done_notifier(&bus->machine_done);
 
-    vmstate_register(NULL, -1, &vmstate_pcibus, bus);
+    vmstate_register(NULL, VMSTATE_INSTANCE_ID_ANY, &vmstate_pcibus, bus);
 }
 
 static void pcie_bus_realize(BusState *qbus, Error **errp)
diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 514a17ae74..a316399ae9 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -3029,7 +3029,7 @@ static void spapr_machine_init(MachineState *machine)
      * interface, this is a legacy from the sPAPREnvironment structure
      * which predated MachineState but had a similar function */
     vmstate_register(NULL, 0, &vmstate_spapr, spapr);
-    register_savevm_live("spapr/htab", -1, 1,
+    register_savevm_live("spapr/htab", VMSTATE_INSTANCE_ID_ANY, 1,
                          &savevm_htab_handlers, spapr);
 
     qbus_set_hotplug_handler(sysbus_get_default(), OBJECT(machine),
diff --git a/hw/timer/arm_timer.c b/hw/timer/arm_timer.c
index c2e6211188..1e9dea451a 100644
--- a/hw/timer/arm_timer.c
+++ b/hw/timer/arm_timer.c
@@ -174,7 +174,7 @@ static arm_timer_state *arm_timer_init(uint32_t freq)
 
     bh = qemu_bh_new(arm_timer_tick, s);
     s->timer = ptimer_init(bh, PTIMER_POLICY_DEFAULT);
-    vmstate_register(NULL, -1, &vmstate_arm_timer, s);
+    vmstate_register(NULL, VMSTATE_INSTANCE_ID_ANY, &vmstate_arm_timer, s);
     return s;
 }
 
diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c
index 22f9113432..da7b490489 100644
--- a/hw/tpm/tpm_emulator.c
+++ b/hw/tpm/tpm_emulator.c
@@ -914,7 +914,8 @@ static void tpm_emulator_inst_init(Object *obj)
     tpm_emu->cur_locty_number = ~0;
     qemu_mutex_init(&tpm_emu->mutex);
 
-    vmstate_register(NULL, -1, &vmstate_tpm_emulator, obj);
+    vmstate_register(NULL, VMSTATE_INSTANCE_ID_ANY,
+                     &vmstate_tpm_emulator, obj);
 }
 
 /*
diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h
index 1fbfd099dd..c551470299 100644
--- a/include/migration/vmstate.h
+++ b/include/migration/vmstate.h
@@ -1113,6 +1113,8 @@ int vmstate_save_state_v(QEMUFile *f, const VMStateDescription *vmsd,
 
 bool vmstate_save_needed(const VMStateDescription *vmsd, void *opaque);
 
+#define  VMSTATE_INSTANCE_ID_ANY  -1
+
 /* Returns: 0 on success, -1 on failure */
 int vmstate_register_with_alias_id(DeviceState *dev, int instance_id,
                                    const VMStateDescription *vmsd,
diff --git a/migration/savevm.c b/migration/savevm.c
index bb9462a54d..0074572a52 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -750,7 +750,7 @@ int register_savevm_live(const char *idstr,
 
     pstrcat(se->idstr, sizeof(se->idstr), idstr);
 
-    if (instance_id == -1) {
+    if (instance_id == VMSTATE_INSTANCE_ID_ANY) {
         se->instance_id = calculate_new_instance_id(se->idstr);
     } else {
         se->instance_id = instance_id;
@@ -817,14 +817,14 @@ int vmstate_register_with_alias_id(DeviceState *dev, int instance_id,
 
             se->compat = g_new0(CompatEntry, 1);
             pstrcpy(se->compat->idstr, sizeof(se->compat->idstr), vmsd->name);
-            se->compat->instance_id = instance_id == -1 ?
+            se->compat->instance_id = instance_id == VMSTATE_INSTANCE_ID_ANY ?
                          calculate_compat_instance_id(vmsd->name) : instance_id;
-            instance_id = -1;
+            instance_id = VMSTATE_INSTANCE_ID_ANY;
         }
     }
     pstrcat(se->idstr, sizeof(se->idstr), vmsd->name);
 
-    if (instance_id == -1) {
+    if (instance_id == VMSTATE_INSTANCE_ID_ANY) {
         se->instance_id = calculate_new_instance_id(se->idstr);
     } else {
         se->instance_id = instance_id;
-- 
2.21.0