[btrfs-devel][patch]fix for btrfs_truncate_in_trans

[Christoph Hellwig]

On Tue, Sep 18, 2007 at 10:13:13AM -0400, Chris Mason wrote:
> try_release_extent_mapping should also be changed not to drop things
> from the extent mapping tree if they are EXTENT_MAP_DELALLOC.

What XFS does here and what I plan to port over to the extent_map
code is that ->releasepage will start the delalloc conversion so that
the page is a simple dirty page and we can drop it, but not actually
start I/O.