Redefine dfs filter type to avoid prealloc problem by making one
large chunk into multiple smaller chunks.
With current data structure, dfs attach was requesting huge chunk
of memory from the heap which results in failure.
Fix is to modify the data structure so that one large chunk
is made as multiple smaller chunks.
Change-Id: Iaa8d0b1b6e4b192b37e165c936920baa5d10a23b
CRs-Fixed: 2323927
1988b55586