before releasing our cache reference. Otherwise removing a vnode (triggered by releasing the cache in our thread) could need pages we still own. * Put the caches and pages into a union to save stack space; they are not needed at the same time. git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@23580 a95241bf-73f2-0310-859d-f6bbb57e9c96