US Patent 7546307 Virtual block storage to filesystem translator

A system for a block storage client to work with data blocks in a virtual filesystem (VFS) where the actual data for the data blocks is stored in a real filesystem (RFS). A virtual block mapping table caches references to the actual data in files and directory structures of the RFS. A read mapper then accesses the files and directory structures based on the cached references in the virtual block mapping table, and constructs the data blocks from the files or synthesizes them from the directory structures. And a VFS interface receive read requests from the client, directs the read mapper to prepare the data blocks, and provides the data blocks to the client.