static void commit_complete(BlockJob *job, void *opaque) { CommitBlockJob *s = container_of(job, CommitBlockJob, common); CommitCompleteData *data = opaque; BlockDriverState *active = s->active; BlockDriverState *top = blk_bs(s->top); BlockDriverState *base = blk_bs(s->base); BlockDriverState *overlay_bs = bdrv_find_overlay(active, s->commit_top_bs); int ret = data->ret; bool remove_commit_top_bs = false; /* Make sure overlay_bs and top stay around until bdrv_set_backing_hd() */ bdrv_ref(top); bdrv_ref(overlay_bs); /* Remove base node parent that still uses BLK_PERM_WRITE/RESIZE before * the normal backing chain can be restored. */ blk_unref(s->base); if (!block_job_is_cancelled(&s->common) && ret == 0) { /* success */ ret = bdrv_drop_intermediate(active, s->commit_top_bs, base, s->backing_file_str); } else if (overlay_bs) { /* XXX Can (or should) we somehow keep 'consistent read' blocked even * after the failed/cancelled commit job is gone? If we already wrote * something to base, the intermediate images aren't valid any more. */ remove_commit_top_bs = true; } /* restore base open flags here if appropriate (e.g., change the base back * to r/o). These reopens do not need to be atomic, since we won't abort * even on failure here */ if (s->base_flags != bdrv_get_flags(base)) { bdrv_reopen(base, s->base_flags, NULL); } if (overlay_bs && s->orig_overlay_flags != bdrv_get_flags(overlay_bs)) { bdrv_reopen(overlay_bs, s->orig_overlay_flags, NULL); } g_free(s->backing_file_str); blk_unref(s->top); block_job_completed(&s->common, ret); g_free(data); /* If bdrv_drop_intermediate() didn't already do that, remove the commit * filter driver from the backing chain. Do this as the final step so that * the 'consistent read' permission can be granted. */ if (remove_commit_top_bs) { bdrv_set_backing_hd(overlay_bs, top, &error_abort); } }