Dear all,
I have a simple NV RAM device, for which I wrote a driver. This driver simply allows reads/writes at a given offset from the start, within the addressable range.
Now, I would like to add another layer, that uses the simple device underneath, but builds a more complicated structure on top of it, like accessing a part of the storage space via a key. As I have 3 physical NV RAM devices, I need to be able to apply the new layer to a selected storage device only. It would be even better if the selection of the NV RAM device to be used with the new layer could be postponed for later and driven by an application.
What would be the best arrangement for this scenario? A filter driver? Could the filter driver be inserted into the device stack after the simple driver has been loaded and running?
Is it possible not to go down the filter driver path? Eg., just have a completely separate, software driver, that opens the simple device in an exclusive mode, and then implements the access functionality I want?
Thanks