qemu/migration/global_state.c
Dr. David Alan Gilbert 44b1ff319c migration: pre_save return int
Modify the pre_save method on VMStateDescription to return an int
rather than void so that it potentially can fail.

Changed zillions of devices to make them return 0; the only
case I've made it return non-0 is hw/intc/s390_flic_kvm.c that already
had an error_report/return case.

Note: If you add an error exit in your pre_save you must emit
an error_report to say why.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170925112917.21340-2-dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2017-09-27 11:35:59 +01:00

134 lines
3 KiB
C

/*
* Global State configuration
*
* Copyright (c) 2014-2017 Red Hat Inc
*
* Authors:
* Juan Quintela <quintela@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "qemu/cutils.h"
#include "qemu/error-report.h"
#include "qapi/error.h"
#include "migration.h"
#include "migration/global_state.h"
#include "migration/vmstate.h"
#include "trace.h"
typedef struct {
uint32_t size;
uint8_t runstate[100];
RunState state;
bool received;
} GlobalState;
static GlobalState global_state;
int global_state_store(void)
{
if (!runstate_store((char *)global_state.runstate,
sizeof(global_state.runstate))) {
error_report("runstate name too big: %s", global_state.runstate);
trace_migrate_state_too_big();
return -EINVAL;
}
return 0;
}
void global_state_store_running(void)
{
const char *state = RunState_str(RUN_STATE_RUNNING);
strncpy((char *)global_state.runstate,
state, sizeof(global_state.runstate));
}
bool global_state_received(void)
{
return global_state.received;
}
RunState global_state_get_runstate(void)
{
return global_state.state;
}
static bool global_state_needed(void *opaque)
{
GlobalState *s = opaque;
char *runstate = (char *)s->runstate;
/* If it is not optional, it is mandatory */
if (migrate_get_current()->store_global_state) {
return true;
}
/* If state is running or paused, it is not needed */
if (strcmp(runstate, "running") == 0 ||
strcmp(runstate, "paused") == 0) {
return false;
}
/* for any other state it is needed */
return true;
}
static int global_state_post_load(void *opaque, int version_id)
{
GlobalState *s = opaque;
Error *local_err = NULL;
int r;
char *runstate = (char *)s->runstate;
s->received = true;
trace_migrate_global_state_post_load(runstate);
r = qapi_enum_parse(&RunState_lookup, runstate, -1, &local_err);
if (r == -1) {
if (local_err) {
error_report_err(local_err);
}
return -EINVAL;
}
s->state = r;
return 0;
}
static int global_state_pre_save(void *opaque)
{
GlobalState *s = opaque;
trace_migrate_global_state_pre_save((char *)s->runstate);
s->size = strlen((char *)s->runstate) + 1;
return 0;
}
static const VMStateDescription vmstate_globalstate = {
.name = "globalstate",
.version_id = 1,
.minimum_version_id = 1,
.post_load = global_state_post_load,
.pre_save = global_state_pre_save,
.needed = global_state_needed,
.fields = (VMStateField[]) {
VMSTATE_UINT32(size, GlobalState),
VMSTATE_BUFFER(runstate, GlobalState),
VMSTATE_END_OF_LIST()
},
};
void register_global_state(void)
{
/* We would use it independently that we receive it */
strcpy((char *)&global_state.runstate, "");
global_state.received = false;
vmstate_register(NULL, 0, &vmstate_globalstate, &global_state);
}