BFQ is available as a patchset for Linux kernel sources from 2.6.32 plus some patches for the zen kernel. These are new versions of BFQ with respect to the ones you can find on Fabio's site. The latest release is 4.1.0-v7r8.
In the following archive, incremental patches to move from a version of BFQ to the following one, or from a version for a given kernel release to the same version for the following kernel release, can be found in previous_versions_revisions/incremental_patches. Besides, every directory named only with a kernel release number contains the latest version of BFQ for that release. Existing older versions of BFQ for these kernels can be found in previous_versions_revisions.
For each full patchset see README.BFQ for a diffstat and for a brief changelog. A list of known bugs and untested functionalities is instead here.
If useful, here is an example of how to add a BFQ version to a git Linux tree, starting from scratch and using git am.