On Thu, 9 Feb 2012, Hannes wrote:
I was under the impression that the ZFS kernel code in FreeBSD is original work under the 2C-BSDL . At least the headers in/usr/src/sys/cddl/compat/opensolaris/kern give this impression. So only the userland code (lib and tools) is under CDDL.
My impression was that there was a specific effort to implement a set of headers and in-kernel hooks as original work under the BSDL, that would be sufficient to allow a CDDL-licensed module to be loaded at runtime and still supply ZFS functionality. This way, the stock kernel that is shipped is entirely BSDL, but the existing bulk of the CDDL ZFS code can be used with only minimal changes for compatibility. /usr/src/sys/modules/zfs/Makefile is enlightening on where things come from, most notably /usr/src/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/.
These files have the CDDL header in them. -Ben Kaduk