config COWLOOP
	tristate "copy-on-write pseudo Block Driver"
	depends on BLOCK
	default n
	---help---
	  Cowloop is a "copy-on-write" pseudo block driver. It can be
	  stacked on top of a "real" block driver, and catches all write
	  operations on their way from the file systems layer above to
	  the real driver below, effectively shielding the lower driver
	  from those write accesses. The requests are then diverted to
	  an ordinary file, located somewhere else (configurable). Later
	  read requests are checked to see whether they can be serviced
	  by the "real" block driver below, or must be pulled in from
	  the diverted location. More information and userspace tools to
	  use the driver are on the project's website
	  http://www.ATComputing.nl/cowloop/