There are four bunkhouses at each corner of the wall. All use the same "10 bunks below, weapon storage above" layout.

There is a hatch in the central courtyard leading to what isn't [i]technically[/i] a dungeon. More of an oubliette.
Turns out you don't take many prisoners out here.

On the east wall is the stables.

Between the northern two bunkhouses, and similarly built into the wall, is the main keep. Upon first walking in, you'd find yourself in a high-ceiling'd room that doubles as receiving area and mess hall. To the right is the kitchen, and below that, the larder. To the left is Commander Dundach's personal quarters and study.
At the back of the room is a staircase leading up to the wall.