Patent ID: 7426611

Claim:
A method comprising: maintaining a first cache, wherein said maintaining is performed by one of an upper-level system and a lower-level storage module, and said first cache is configured to provide read access and write access by said one of said upper-level system and said lower-level storage module; cloning information stored in a first unit of storage into a second unit of storage, wherein said first cache comprises said first unit of storage and a second cache comprises said second unit of storage; and accessing said second cache, wherein said accessing is performed by the other of said upper-level system and said lower-level storage module, said second cache is configured to provide read access and write access by said other of said upper-level system and said lower-level storage module, and said accessing is performed using at least one of a set of interfaces, wherein said set of interfaces is exported from said one of said upper-level system and said lower-level storage module to said other of said upper-level system and said lower-level storage module.