As one of the ZoL developers, I must say that these remarks are rather hurtful. It is bad enough having to deal with this attitude from mainline Linux, but being accused of it is rather nasty.I do not have high hopes of this happening. The velocity of change in Linux is too drastic, and they've had a track record of unwillingness to take in account the needs of other platforms, or to maintain interoperability of software.
There will be a culture clash - because we (FreeBSD) have different values and approach to software development. I suspect a scenario where the Linux commits will be more frequent (which have been - due to a larger developer base). These commits will assume Linux interfaces or have fundamental changes to the inner-pinnings of ZFS, which will hamper FreeBSDs ability to merge improvements with the least of amount of friction. Or code quality will suffer. Linux's response will be "Sorry bro!, this is how we work - take it or leave it", and it all goes down from there.
Maybe I'm just being pessimistic about the situation - but i do not trust Linux to be fair and handle a project of such magnitude and prestige. Their culture just doesn't permeate reasonable values.
I will admit that there was an instance where I complained about bashisms in the code and my complaints were overruled, but with FreeBSD support being added to the tree, getting those bashisms fixed will be fairly easy. That is trivial in comparison to the ZTS that was added long after those complaints, but Matt Macy is working on that and myself and others are available to him to answer questions and give advice.
Aside from those issues with some scripts, we make an effort to have platform independent code (to support as many Linux user lands as possible) and that effort will only become stronger after FreeBSD is added. While I do not maintain the test infrastructure, I expect that FreeBSD will be integrated into the buildbot such that anything that causes a regression on FreeBSD will prevent a patch from being merged. It is like this for all of the Linux distributions that are part of the builbot.
Anyway, I am thrilled to see the codebase being unified with the incoming addition of FreeBSD support to the repository. After FreeBSD is added, it will be easier to add Mac OS X, Windows, Illumos, FUSE, NetBSD, etcetera as targets, I am looking forward to that. Also, doing unification with FreeBSD’s ZFS driver will allow for the ZoL packaging to be reused for the FreeBSD kernel + FreeBSD userland on Gentoo when they are used in place of Linux and GNU. As the person responsible for the Gentoo ZFS packaging, I find that awesome,
Lastly, nothing prevents people from doing distribution specific stuff outside of the repository. Before someone points out the differences between FreeBSD and Linux distributions, I would like to state that BSD stands for the Berkeley Software Distribution. It would be best for everyone if we unified the codebase so that patches can go back and forth, but if we are moving too slowly at merging something, it need not block that from being in FreeBSD’s ZFS code.