@@ -423,6 +423,7 @@ void qcow2_snapshot_create(BlockDriverState *bs,
int i, ret;
uint64_t *l1_table = NULL;
int64_t l1_table_offset;
+ Error *err_rollback = NULL;
memset(sn, 0, sizeof(*sn));
@@ -471,7 +472,7 @@ void qcow2_snapshot_create(BlockDriverState *bs,
PRIu64 " with size %" PRIu64,
sn->l1_table_offset,
(uint64_t)(s->l1_size * sizeof(uint64_t)));
- goto fail;
+ goto dealloc_l1_table;
}
ret = bdrv_pwrite(bs->file, sn->l1_table_offset, l1_table,
@@ -482,7 +483,7 @@ void qcow2_snapshot_create(BlockDriverState *bs,
PRIu64 " with size %" PRIu64,
sn->l1_table_offset,
(uint64_t)(s->l1_size * sizeof(uint64_t)));
- goto fail;
+ goto dealloc_l1_table;
}
g_free(l1_table);
@@ -499,7 +500,7 @@ void qcow2_snapshot_create(BlockDriverState *bs,
"Failed in update of refcount for snapshot at %"
PRIu64 " with size %d",
s->l1_table_offset, s->l1_size);
- goto fail;
+ goto dealloc_l1_table;
}
/* Append the new snapshot to the snapshot list */
@@ -512,12 +513,18 @@ void qcow2_snapshot_create(BlockDriverState *bs,
s->snapshots = new_snapshot_list;
s->snapshots[s->nb_snapshots++] = *sn;
- ret = qcow2_write_snapshots(bs, errp, NULL);
+ ret = qcow2_write_snapshots(bs, errp, &err_rollback);
if (ret < 0) {
g_free(s->snapshots);
s->snapshots = old_snapshot_list;
s->nb_snapshots--;
- goto fail;
+ if (error_is_set(&err_rollback)) {
+ error_append(errp, "%s", error_get_pretty(err_rollback));
+ error_free(err_rollback);
+ goto fail;
+ } else {
+ goto restore_refcount;
+ }
}
g_free(old_snapshot_list);
@@ -537,6 +544,26 @@ void qcow2_snapshot_create(BlockDriverState *bs,
#endif
return;
+restore_refcount:
+ if (qcow2_update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, -1)
+ < 0) {
+ /* Nothing can be done now, need image check later, skip following
+ rollback action. */
+ error_append(errp,
+ "In rollback failed to restore refcount in snapshot");
+ goto fail;
+ }
+
+dealloc_l1_table:
+ ret = qcow2_free_clusters(bs, sn->l1_table_offset,
+ sn->l1_size * sizeof(uint64_t),
+ QCOW2_DISCARD_ALWAYS);
+ if (ret < 0) {
+ error_append(errp,
+ "In rollback failed to free L1 table: %s\n",
+ strerror(-ret));
+ }
+
fail:
g_free(sn->id_str);
g_free(sn->name);
A new variable *err_rollback is added to detect sub function's rollback failure. If one step in rollback procedure fails, following steps will be skipped, and the error message will be appended to errp. Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> --- block/qcow2-snapshot.c | 37 ++++++++++++++++++++++++++++++++----- 1 files changed, 32 insertions(+), 5 deletions(-)