[OSM-newbies] roads with bollards or other obstruction

[Daniel Would]

Hi,
I'm in the process of mapping Eastleigh, and something I've found  
common is roads that either have bollards blocking through traffic,  
or perhaps just pavement/tree stopping it connecting to a main road,  
but the road carries on on the other side of the cross road.
How do I tag this so that it shows as a whole road, but is clear that  
cars can't get past certain parts? (does this description even make  
sense?

Cheers

Dan