From what I can tell, no. However, I generated a diff (which can be found here) between the 2.6.28.10 snapshot and latest on http://git.kernel.org/?p=linux/kerne...-stable-2.6.28 and fixed the few discrepancies, so that it now patches against kernel-power47 (and BFS ). Some had already been applied, some had been partially applied and one had had "force_da_alloc=1" added whereas the diff had an if statement added as well (so I went with the latter).

Please note that the patch has been updated since my original post - I'd erroneously included part of the ioctl.c diff that had already been applied, and although it would patch successfully it wouldn't compile (due to a duplicate case statement).

PS: I tried Reiser4, even added an edit into the wiki, but I had to backtrack as it was hammering my CPU and also I had the dmesg errors even with cluster=32K. Basically, my N900 just didn't like it one bit, which is a real shame I'd love to try out btrfs, but I can't find a backport to 2.6.28 anywhere (and it's only really been stable since 2.6.32 anyway) so it's probably not worth the trouble.