LXR qemu/migration/global

   1/*
   2 * Global State configuration
   3 *
   4 * Copyright (c) 2014-2017 Red Hat Inc
   5 *
   6 * Authors:
   7 *  Juan Quintela <quintela@redhat.com>
   8 *
   9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
  10 * See the COPYING file in the top-level directory.
  11 */
  12
  13#include "qemu/osdep.h"
  14#include "qemu/cutils.h"
  15#include "qemu/error-report.h"
  16#include "qapi/error.h"
  17#include "migration.h"
  18#include "migration/global_state.h"
  19#include "migration/vmstate.h"
  20#include "trace.h"
  21
  22typedef struct {
  23    uint32_t size;
  24    uint8_t runstate[100];
  25    RunState state;
  26    bool received;
  27} GlobalState;
  28
  29static GlobalState global_state;
  30
  31int global_state_store(void)
  32{
  33    if (!runstate_store((char *)global_state.runstate,
  34                        sizeof(global_state.runstate))) {
  35        error_report("runstate name too big: %s", global_state.runstate);
  36        trace_migrate_state_too_big();
  37        return -EINVAL;
  38    }
  39    return 0;
  40}
  41
  42void global_state_store_running(void)
  43{
  44    const char *state = RunState_str(RUN_STATE_RUNNING);
  45    strncpy((char *)global_state.runstate,
  46           state, sizeof(global_state.runstate));
  47}
  48
  49bool global_state_received(void)
  50{
  51    return global_state.received;
  52}
  53
  54RunState global_state_get_runstate(void)
  55{
  56    return global_state.state;
  57}
  58
  59static bool global_state_needed(void *opaque)
  60{
  61    GlobalState *s = opaque;
  62    char *runstate = (char *)s->runstate;
  63
  64    /* If it is not optional, it is mandatory */
  65
  66    if (migrate_get_current()->store_global_state) {
  67        return true;
  68    }
  69
  70    /* If state is running or paused, it is not needed */
  71
  72    if (strcmp(runstate, "running") == 0 ||
  73        strcmp(runstate, "paused") == 0) {
  74        return false;
  75    }
  76
  77    /* for any other state it is needed */
  78    return true;
  79}
  80
  81static int global_state_post_load(void *opaque, int version_id)
  82{
  83    GlobalState *s = opaque;
  84    Error *local_err = NULL;
  85    int r;
  86    char *runstate = (char *)s->runstate;
  87
  88    s->received = true;
  89    trace_migrate_global_state_post_load(runstate);
  90
  91    r = qapi_enum_parse(&RunState_lookup, runstate, -1, &local_err);
  92
  93    if (r == -1) {
  94        if (local_err) {
  95            error_report_err(local_err);
  96        }
  97        return -EINVAL;
  98    }
  99    s->state = r;
 100
 101    return 0;
 102}
 103
 104static int global_state_pre_save(void *opaque)
 105{
 106    GlobalState *s = opaque;
 107
 108    trace_migrate_global_state_pre_save((char *)s->runstate);
 109    s->size = strlen((char *)s->runstate) + 1;
 110
 111    return 0;
 112}
 113
 114static const VMStateDescription vmstate_globalstate = {
 115    .name = "globalstate",
 116    .version_id = 1,
 117    .minimum_version_id = 1,
 118    .post_load = global_state_post_load,
 119    .pre_save = global_state_pre_save,
 120    .needed = global_state_needed,
 121    .fields = (VMStateField[]) {
 122        VMSTATE_UINT32(size, GlobalState),
 123        VMSTATE_BUFFER(runstate, GlobalState),
 124        VMSTATE_END_OF_LIST()
 125    },
 126};
 127
 128void register_global_state(void)
 129{
 130    /* We would use it independently that we receive it */
 131    strcpy((char *)&global_state.runstate, "");
 132    global_state.received = false;
 133    vmstate_register(NULL, 0, &vmstate_globalstate, &global_state);
 134}
 135