int qcow2_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
{
BDRVQcowState *s = bs->opaque;
QCowSnapshot *sn;
int snapshot_index, ret;
snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id);
if (snapshot_index < 0)
return -ENOENT;
sn = &s->snapshots[snapshot_index];
ret = qcow2_update_snapshot_refcount(bs, sn->l1_table_offset, sn->l1_size, -1);
if (ret < 0)
return ret;
ret = qcow2_update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 0);
if (ret < 0)
return ret;
qcow2_free_clusters(bs, sn->l1_table_offset, sn->l1_size * sizeof(uint64_t));
qemu_free(sn->id_str);
qemu_free(sn->name);
memmove(sn, sn + 1, (s->nb_snapshots - snapshot_index - 1) * sizeof(*sn));
s->nb_snapshots--;
ret = qcow_write_snapshots(bs);
if (ret < 0) {
return ret;
}
#ifdef DEBUG_ALLOC
qcow2_check_refcounts(bs);
#endif
return 0;
}
/* if no id is provided, a new one is constructed */
int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info)
{
BDRVQcowState *s = bs->opaque;
QCowSnapshot *snapshots1, sn1, *sn = &sn1;
int i, ret;
uint64_t *l1_table = NULL;
memset(sn, 0, sizeof(*sn));
if (sn_info->id_str[0] == '\0') {
/* compute a new id */
find_new_snapshot_id(bs, sn_info->id_str, sizeof(sn_info->id_str));
}
/* check that the ID is unique */
if (find_snapshot_by_id(bs, sn_info->id_str) >= 0)
return -ENOENT;
sn->id_str = qemu_strdup(sn_info->id_str);
if (!sn->id_str)
goto fail;
sn->name = qemu_strdup(sn_info->name);
if (!sn->name)
goto fail;
sn->vm_state_size = sn_info->vm_state_size;
sn->date_sec = sn_info->date_sec;
sn->date_nsec = sn_info->date_nsec;
sn->vm_clock_nsec = sn_info->vm_clock_nsec;
ret = qcow2_update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1);
if (ret < 0)
goto fail;
/* create the L1 table of the snapshot */
sn->l1_table_offset = qcow2_alloc_clusters(bs, s->l1_size * sizeof(uint64_t));
sn->l1_size = s->l1_size;
l1_table = qemu_malloc(s->l1_size * sizeof(uint64_t));
for(i = 0; i < s->l1_size; i++) {
l1_table[i] = cpu_to_be64(s->l1_table[i]);
}
if (bdrv_pwrite(s->hd, sn->l1_table_offset,
l1_table, s->l1_size * sizeof(uint64_t)) !=
(s->l1_size * sizeof(uint64_t)))
goto fail;
qemu_free(l1_table);
l1_table = NULL;
snapshots1 = qemu_malloc((s->nb_snapshots + 1) * sizeof(QCowSnapshot));
if (s->snapshots) {
memcpy(snapshots1, s->snapshots, s->nb_snapshots * sizeof(QCowSnapshot));
qemu_free(s->snapshots);
}
s->snapshots = snapshots1;
s->snapshots[s->nb_snapshots++] = *sn;
if (qcow_write_snapshots(bs) < 0)
goto fail;
#ifdef DEBUG_ALLOC
qcow2_check_refcounts(bs);
#endif
return 0;
fail:
qemu_free(sn->name);
qemu_free(l1_table);
return -1;
}
