origin_dev_id    3742 drivers/md/dm-thin.c 	dm_thin_id origin_dev_id;
origin_dev_id    3753 drivers/md/dm-thin.c 	r = read_dev_id(argv[2], &origin_dev_id, 1);
origin_dev_id    3757 drivers/md/dm-thin.c 	r = dm_pool_create_snap(pool->pmd, dev_id, origin_dev_id);