ZFS as a Linux kernel module
According to a report by Phoronix, Indian vendor Knowledge Quest Infotech is working on a native ZFS port to Linux. The company, whose areas of expertise include the Linux kernel and cluster file systems, reportedly plans to release the port in mid-September.
The problem with ZFS for Linux lies in licence incompatibilities: ZFS is released under the CDDL, the Linux kernel under the GPL. As a result, it is impossible (and, according to Phoronix, there are no plans) to integrate ZFS into the kernel sources, or to allow a ZFS implementation maintained independently of the Linux kernel to use kernel code which is licensed under the GPL. However, Phoronix says that KQ Infotech has found a solution which conforms with the licensing requirements.
This solution involves releasing ZFS as a pre-compiled kernel module for Fedora 12 and Red Hat Enterprise Linux 6 Beta 2, while the users of other current Linux distributions such as Ubuntu 10.04 will need to compile the code themselves. Unlike the ZFS port created by the Lawrence Livermore National Laboratory in co-operation with Oracle, the ZFS port by Knowledge Quest Infotech is also planned to implement the ZFS Posix Layer, which is the interface to the operating system. Phoronix has already threatened to run benchmarks.