in my fsf driver i am getting FastIoDeviceControl to my CDO. value of IOCTL is 00140FCF. does any one knows what is it and why i am getting it.
It is IOCTL_CSC_DO_SHADOW_MAINTENANCE.
AFAIK this IOCTL is undocumented. The name may not be exact,
I have assumed it because after calling this IOCTL, the
IoctlDoShadowMaintenance is called 
I don’t know why exactly this IOCTL is for, but I am sure that it is
related to the offline folders.
If you’ll watch e.g. offline folders synchronization with FileSpy
(take newer version from http://www.zezula.net/download/filespy.zip),
you’ll see many CSC ioctls going to the network redirector.
L.