The game ended 3-1 to Villa, with all three goals occurring in the first half.
Scott Hogan gave Villa a big early lead with two goals in three minutes, leaving Villa leading 2-0 after only 7 minutes.
Barnsley fought hard in the second half for another goal, but were denied time and time again by Johnstone, who had a superb second half performance.
Watch all the goals and highlights below, courtesy of Barnsley:
This was Villa's fourth straight league game win, they will be hoping to continue this run away against Sheffield United, on Tuesday 30th January.
Another great afternoon. Well done everyone!#PartOfThePride#AVFCpic.twitter.com/DZLdVDTF7e
— Aston Villa FC (@AVFCOfficial) January 20, 2018