Hello, I've been testing btrfs on a linux/ppc with a 2.6.20 kernel. For that I needed to apply a minor patch for <v0.13 (related to the definition of ,write_cache_pages()). For v0.13 it required the patch for the endianess bug in crc32 due to the change in the crc32c() implementation on linux-2.6.23, that I've posted here before. I've just pulled the unstable tree, and tried to build, but it doesn't even compile, I've found yet one more changed function declaration : linux-2.6.20: include/linux/bio.h:extern void bio_endio(struct bio *, unsigned int, int); linux-2.6.24: include/linux/bio.h:extern void bio_endio(struct bio *, int); and also some missing functions: (bdi_ini()t, bdi_destroy()). (not found in 2.6.23 and older) linux-2.6.24: include/linux/backing-dev.h:int bdi_init(struct backing_dev_info *bdi); linux-2.6.24: include/linux/backing-dev.h:void bdi_destroy(struct backing_dev_info *bdi); Should I include the code from 2.6.24 for bdi_init and bdi_destroy in btrfs, and wrap it around ifdefs ? My question is, is there sill interestest in having btrfs compatible with older kernels (like, 2.6.20 or 2.6.18)? I'll post (or repost) patches that I need for btrfs-unstable to build/work on this ppc system of mine. Kind regards, -- Miguel Sousa Filipe
On Sat, Apr 05, 2008 at 08:13:47PM +0100, Miguel Sousa Filipe wrote:> My question is, is there sill interestest in having btrfs compatible > with older kernels (like, 2.6.20 or 2.6.18)? > I'll post (or repost) patches that I need for btrfs-unstable to > build/work on this ppc system of mine.It sort of depends who you ask. Personally, I see value in being compatible with as wide range of kernels as possible in a development filesystem that you want people to be testing. But then I'm not doing any btrfs development, so I don't count for much. Other people, well - Christoph Hellwig had this to say a little while back in <20080207044835.GC4140 at lst.de> (rewrapped): On Wed, Feb 06, 2008 at 05:14:51PM -0500, Jeff Mahoney wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Kernels prior to 2.6.19 don't export file_ra_state_init(). > This patch adds the file_ra_state_init() from 2.6.18. Please put this somewhere else, a separate file and hopefully only in your backports tree. This is kernels from stoneage after all, not just one or two revisions back. Bron ( not being particularly helpful or even answering your question really )
On Saturday 05 April 2008, Miguel Sousa Filipe wrote:> My question is, is there sill interestest in having btrfs compatible > with older kernels (like, 2.6.20 or 2.6.18)? > I'll post (or repost) patches that I need for btrfs-unstable to > build/work on this ppc system of mine.Definitely. Just to confirm what Zach said over the weekend, at this stage in the game it is much more important to me to keep btrfs easy for testers than it is to avoid small amounts of compat code. So, any fixes would definitely be appreciated. -chris