ZPOOL_TRIM_COMMAND
fnvlist_add_uint64(args, ZPOOL_TRIM_COMMAND, (uint64_t)cmd_type);
fnvlist_add_uint64(required, ZPOOL_TRIM_COMMAND, POOL_TRIM_START);
{ZPOOL_TRIM_COMMAND, DATA_TYPE_UINT64, 0},
if (nvlist_lookup_uint64(innvl, ZPOOL_TRIM_COMMAND, &cmd_type) != 0)