Run your NFS server in the user address space with NFS-GANESHA

“NFS-GANESHA accesses the underlying data through a File System
Abstraction Layer (FSAL), allowing you to plug in your own storage
mechanism and access it from any NFS client. NFS-GANESHA provides a
FUSE-compatible FSAL to allow you to quickly access a FUSE
filesystem over NFS while avoiding the need for data to bounce
through the kernel FUSE mechanism on the NFS server.

“Why would you want to do this? Running a filesystem out of the
kernel through FUSE lets you use libraries to support your
filesystem’s functionality — for example, you can use Berkeley DB
to store the file contents — and also aids greatly during the
development of your filesystem because a bug in your code won’t
cause the kernel itself to oops. FUSE includes a portion that runs
inside the Linux kernel, which allows applications to use FUSE
filesystems just like any other “regular” kernel filesystem. The
Linux kernel FUSE code communicates with the user address space
FUSE filesystems on behalf of the application whenever you use a
FUSE filesystem. One downside of all of this is that some FUSE
filesystems don’t like being exported over NFS.”

Complete
Story