NBD_CMD_PARTIAL_SEND
if (test_bit(NBD_CMD_PARTIAL_SEND, &cmd->flags)) {
WARN_ON_ONCE(test_bit(NBD_CMD_PARTIAL_SEND, &cmd->flags));
set_bit(NBD_CMD_PARTIAL_SEND, &cmd->flags);
if (test_bit(NBD_CMD_PARTIAL_SEND, &cmd->flags))
if (WARN_ON_ONCE(!test_bit(NBD_CMD_PARTIAL_SEND, &cmd->flags)))
clear_bit(NBD_CMD_PARTIAL_SEND, &cmd->flags);