default or selected kernelversion does not have config value CONFIG_COWLOOP.
Result is shown for kernelversion 5.15.31
copy-on-write pseudo Block Driver
modulename: cowloop.ko
configname: CONFIG_COWLOOP
Linux Kernel Configuration
└─>Device Drivers
└─>Staging drivers
└─>copy-on-write pseudo Block Driver
In linux kernel since version 2.6.32.1 (release Date: 2009-12-14)
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/
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/