reset: Use ResetType for qemu_devices_reset() and MachineClass::reset()

Currently, both qemu_devices_reset() and MachineClass::reset() use
ShutdownCause for the reason of the reset. However, the Resettable
interface uses ResetState, so ShutdownCause needs to be translated to
ResetType somewhere. Translating it qemu_devices_reset() makes adding
new reset types harder, as they cannot always be matched to a single
ShutdownCause here, and devices may need to check the ResetType to
determine what to reset and if to reset at all.

This patch moves this translation up in the call stack to
qemu_system_reset() and updates all MachineClass children to use the
ResetType instead.

Message-ID: <20240904103722.946194-2-jmarcin@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Juraj Marcin <jmarcin@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>

hw/arm/aspeed.c

@@ -1529,12 +1529,12 @@ static void aspeed_machine_bletchley_class_init(ObjectClass *oc, void *data)
     aspeed_machine_class_init_cpus_defaults(mc);
 }
 
-static void fby35_reset(MachineState *state, ShutdownCause reason)
+static void fby35_reset(MachineState *state, ResetType type)
 {
     AspeedMachineState *bmc = ASPEED_MACHINE(state);
     AspeedGPIOState *gpio = &bmc->soc->gpio;
 
-    qemu_devices_reset(reason);
+    qemu_devices_reset(type);
 
     /* Board ID: 7 (Class-1, 4 slots) */
     object_property_set_bool(OBJECT(gpio), "gpioV4", true, &error_fatal);

hw/arm/mps2-tz.c

@@ -1254,7 +1254,7 @@ static void mps2_set_remap(Object *obj, const char *value, Error **errp)
     }
 }
 
-static void mps2_machine_reset(MachineState *machine, ShutdownCause reason)
+static void mps2_machine_reset(MachineState *machine, ResetType type)
 {
     MPS2TZMachineState *mms = MPS2TZ_MACHINE(machine);
 
@@ -1264,7 +1264,7 @@ static void mps2_machine_reset(MachineState *machine, ShutdownCause reason)
      * reset see the correct mapping.
      */
     remap_memory(mms, mms->remap);
-    qemu_devices_reset(reason);
+    qemu_devices_reset(type);
 }
 
 static void mps2tz_class_init(ObjectClass *oc, void *data)

hw/core/reset.c

@@ -170,11 +170,8 @@ void qemu_unregister_resettable(Object *obj)
     resettable_container_remove(get_root_reset_container(), obj);
 }
 
-void qemu_devices_reset(ShutdownCause reason)
+void qemu_devices_reset(ResetType type)
 {
-    ResetType type = (reason == SHUTDOWN_CAUSE_SNAPSHOT_LOAD) ?
-        RESET_TYPE_SNAPSHOT_LOAD : RESET_TYPE_COLD;
-
     /* Reset the simulation */
     resettable_reset(OBJECT(get_root_reset_container()), type);
 }

hw/hppa/machine.c

@@ -642,12 +642,12 @@ static void machine_HP_C3700_init(MachineState *machine)
     machine_HP_common_init_tail(machine, pci_bus, translate);
 }
 
-static void hppa_machine_reset(MachineState *ms, ShutdownCause reason)
+static void hppa_machine_reset(MachineState *ms, ResetType type)
 {
     unsigned int smp_cpus = ms->smp.cpus;
     int i;
 
-    qemu_devices_reset(reason);
+    qemu_devices_reset(type);
 
     /* Start all CPUs at the firmware entry point.
      *  Monarch CPU will initialize firmware, secondary CPUs

hw/i386/microvm.c

@@ -462,7 +462,7 @@ static void microvm_machine_state_init(MachineState *machine)
     microvm_devices_init(mms);
 }
 
-static void microvm_machine_reset(MachineState *machine, ShutdownCause reason)
+static void microvm_machine_reset(MachineState *machine, ResetType type)
 {
     MicrovmMachineState *mms = MICROVM_MACHINE(machine);
     CPUState *cs;
@@ -475,7 +475,7 @@ static void microvm_machine_reset(MachineState *machine, ShutdownCause reason)
         mms->kernel_cmdline_fixed = true;
     }
 
-    qemu_devices_reset(reason);
+    qemu_devices_reset(type);
 
     CPU_FOREACH(cs) {
         cpu = X86_CPU(cs);

hw/i386/pc.c

@@ -1712,12 +1712,12 @@ static void pc_machine_initfn(Object *obj)
     qemu_add_machine_init_done_notifier(&pcms->machine_done);
 }
 
-static void pc_machine_reset(MachineState *machine, ShutdownCause reason)
+static void pc_machine_reset(MachineState *machine, ResetType type)
 {
     CPUState *cs;
     X86CPU *cpu;
 
-    qemu_devices_reset(reason);
+    qemu_devices_reset(type);
 
     /* Reset APIC after devices have been reset to cancel
      * any changes that qemu_devices_reset() might have done.
@@ -1732,7 +1732,7 @@ static void pc_machine_reset(MachineState *machine, ShutdownCause reason)
 static void pc_machine_wakeup(MachineState *machine)
 {
     cpu_synchronize_all_states();
-    pc_machine_reset(machine, SHUTDOWN_CAUSE_NONE);
+    pc_machine_reset(machine, RESET_TYPE_COLD);
     cpu_synchronize_all_post_reset();
 }
 

hw/ppc/pegasos2.c

@@ -291,14 +291,14 @@ static void pegasos2_superio_write(uint8_t addr, uint8_t val)
     cpu_physical_memory_write(PCI1_IO_BASE + 0x3f1, &val, 1);
 }
 
-static void pegasos2_machine_reset(MachineState *machine, ShutdownCause reason)
+static void pegasos2_machine_reset(MachineState *machine, ResetType type)
 {
     Pegasos2MachineState *pm = PEGASOS2_MACHINE(machine);
     void *fdt;
     uint64_t d[2];
     int sz;
 
-    qemu_devices_reset(reason);
+    qemu_devices_reset(type);
     if (!pm->vof) {
         return; /* Firmware should set up machine so nothing to do */
     }

hw/ppc/pnv.c

@@ -709,13 +709,13 @@ static void pnv_powerdown_notify(Notifier *n, void *opaque)
     }
 }
 
-static void pnv_reset(MachineState *machine, ShutdownCause reason)
+static void pnv_reset(MachineState *machine, ResetType type)
 {
     PnvMachineState *pnv = PNV_MACHINE(machine);
     IPMIBmc *bmc;
     void *fdt;
 
-    qemu_devices_reset(reason);
+    qemu_devices_reset(type);
 
     /*
      * The machine should provide by default an internal BMC simulator.

hw/ppc/spapr.c

@@ -1725,7 +1725,7 @@ void spapr_check_mmu_mode(bool guest_radix)
     }
 }
 
-static void spapr_machine_reset(MachineState *machine, ShutdownCause reason)
+static void spapr_machine_reset(MachineState *machine, ResetType type)
 {
     SpaprMachineState *spapr = SPAPR_MACHINE(machine);
     PowerPCCPU *first_ppc_cpu;
@@ -1733,7 +1733,7 @@ static void spapr_machine_reset(MachineState *machine, ShutdownCause reason)
     void *fdt;
     int rc;
 
-    if (reason != SHUTDOWN_CAUSE_SNAPSHOT_LOAD) {
+    if (type != RESET_TYPE_SNAPSHOT_LOAD) {
         /*
          * Record-replay snapshot load must not consume random, this was
          * already replayed from initial machine reset.
@@ -1762,7 +1762,7 @@ static void spapr_machine_reset(MachineState *machine, ShutdownCause reason)
         spapr_setup_hpt(spapr);
     }
 
-    qemu_devices_reset(reason);
+    qemu_devices_reset(type);
 
     spapr_ovec_cleanup(spapr->ov5_cas);
     spapr->ov5_cas = spapr_ovec_new();

hw/s390x/s390-virtio-ccw.c

@@ -440,7 +440,7 @@ static void s390_pv_prepare_reset(S390CcwMachineState *ms)
     s390_pv_prep_reset();
 }
 
-static void s390_machine_reset(MachineState *machine, ShutdownCause reason)
+static void s390_machine_reset(MachineState *machine, ResetType type)
 {
     S390CcwMachineState *ms = S390_CCW_MACHINE(machine);
     enum s390_reset reset_type;
@@ -472,7 +472,7 @@ static void s390_machine_reset(MachineState *machine, ShutdownCause reason)
          * Device reset includes CPU clear resets so this has to be
          * done AFTER the unprotect call above.
          */
-        qemu_devices_reset(reason);
+        qemu_devices_reset(type);
         s390_crypto_reset();
 
         /* configure and start the ipl CPU only */

include/hw/boards.h

@@ -10,6 +10,7 @@
 #include "qemu/module.h"
 #include "qom/object.h"
 #include "hw/core/cpu.h"
+#include "hw/resettable.h"
 
 #define TYPE_MACHINE_SUFFIX "-machine"
 
@@ -257,7 +258,7 @@ struct MachineClass {
     const char *deprecation_reason;
 
     void (*init)(MachineState *state);
-    void (*reset)(MachineState *state, ShutdownCause reason);
+    void (*reset)(MachineState *state, ResetType type);
     void (*wakeup)(MachineState *state);
     int (*kvm_type)(MachineState *machine, const char *arg);
     int (*hvf_get_physical_address_range)(MachineState *machine);

include/sysemu/reset.h

@@ -27,6 +27,7 @@
 #ifndef QEMU_SYSEMU_RESET_H
 #define QEMU_SYSEMU_RESET_H
 
+#include "hw/resettable.h"
 #include "qapi/qapi-events-run-state.h"
 
 typedef void QEMUResetHandler(void *opaque);
@@ -110,7 +111,7 @@ void qemu_unregister_reset(QEMUResetHandler *func, void *opaque);
 
 /**
  * qemu_devices_reset: Perform a complete system reset
- * @reason: reason for the reset
+ * @reason: type of the reset
  *
  * This function performs the low-level work needed to do a complete reset
  * of the system (calling all the callbacks registered with
@@ -121,6 +122,6 @@ void qemu_unregister_reset(QEMUResetHandler *func, void *opaque);
  * If you want to trigger a system reset from, for instance, a device
  * model, don't use this function. Use qemu_system_reset_request().
  */
-void qemu_devices_reset(ShutdownCause reason);
+void qemu_devices_reset(ResetType type);
 
 #endif

system/runstate.c

@@ -32,6 +32,7 @@
 #include "exec/cpu-common.h"
 #include "gdbstub/syscalls.h"
 #include "hw/boards.h"
+#include "hw/resettable.h"
 #include "migration/misc.h"
 #include "migration/postcopy-ram.h"
 #include "monitor/monitor.h"
@@ -507,15 +508,23 @@ static int qemu_debug_requested(void)
 void qemu_system_reset(ShutdownCause reason)
 {
     MachineClass *mc;
+    ResetType type;
 
     mc = current_machine ? MACHINE_GET_CLASS(current_machine) : NULL;
 
     cpu_synchronize_all_states();
 
+    switch (reason) {
+    case SHUTDOWN_CAUSE_SNAPSHOT_LOAD:
+        type = RESET_TYPE_SNAPSHOT_LOAD;
+        break;
+    default:
+        type = RESET_TYPE_COLD;
+    }
     if (mc && mc->reset) {
-        mc->reset(current_machine, reason);
+        mc->reset(current_machine, type);
     } else {
-        qemu_devices_reset(reason);
+        qemu_devices_reset(type);
     }
     switch (reason) {
     case SHUTDOWN_CAUSE_NONE: