I have not cut or split logs to use in my smoker.But back in my younger days,I did cut my share of wood and sold it.So I guess there is no way of reducing your logs to the size that you want ,without cutting smaller..If you don't have a chain saw,you can either rent one or buy a cheap one for this job.Even an electric one will do.Another way is to take one end of the log and put it in your smoker/grill.Fire up your smoker,and let the log burn down.Of course you will lose a good amount of heat and smoke this way,but you won't have to do all of that hard work.

Be sure to tie a red rag around the piece that's sticking out,you wouldn't want anyone to walk into it.
Bill