- Go to the Jenkins build
- On the left hand side click the Pipeline steps
- Then on the right click on the link that says “Allocate node : Start – (x min in block)”
- On the the left side click the workspace. Done!
The image below might help :

Check out this link it shows how to get the workspace when you are using jenkins pipeline: https://www.selikoff.net/2016/07/10/workspace-jenkins-pipelines/