http://www.cs.uml.edu/~acahalan/ext2.gif
In both ways, the scale goes 1,2,4,8... bits. (log base 2)
The pink area is what I think ext2 could reasonably be extended to.
It would require support for block sizes from 512 bytes to 64 kB
and a 64-bit file offset.
I think the 64-bit API comes first. That would get 4 GB files
without much (any?) change to the main ext2 code.
I can't test any code; this is just very interesting for me.
If only I could buy an 11 TB disk cluster from EMC... :-)
Let me know of any errors in the graph.