On Mon, 31 May 2010 09:20:22 +0200 Andreas Philipp wrote:

> I did not succeed to compile a btrfs module via dkms from btrfs-unstable...
> For the exact error message, please see the make.log...

> /var/lib/dkms/btrfs/git/build/extent-tree.c:1699: error: 
>   ‘DISCARD_FL_BARRIER’ undeclared (first use in this function)

The problem is the blkdev flag name change that occurred in this commit from
Linus' tree around 2.6.35:

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=fbd9b09a177a481eda256447c881f014f29034fe

which is not in btrfs-unstable.  That patch doesn't apply cleanly to the
btrfs-unstable tree so attached is one that just modifies extent-tree.c.

Jim