On Mon, Apr 03, 2017 at 06:09:27PM +0200, Max Reitz wrote:
> Currently, raw_regular_truncate() is intended for setting the size of a
> newly created file. However, we also want to use it for truncating an
> existing file in which case only the newly added space (when growing)
> should be preallocated.
> 
> This also means that if resizing failed, we should try to restore the
> original file size. This is important when using preallocation.
> 
> Signed-off-by: Max Reitz <mreitz@redhat.com>
> ---
>  block/file-posix.c | 61 ++++++++++++++++++++++++++++++++++++++++++++----------
>  1 file changed, 50 insertions(+), 11 deletions(-)

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>