Files full of zeros with coreutils-8.11 and xfs (FIEMAP related?)

Fri Apr 15 12:16:29 CDT 2011

On Fri, Apr 15, 2011 at 10:53:48AM +0200, Jim Meyering wrote:
> Can you or anyone else point to authoritative documentation
> (or even a summary of those "discussions") of FIEMAP semantics?

A large part of the problem is that there's none and the semantics
is a hode-podge of random flags that mostly make little sense
outside of fs developers debugging the layout that we created.  The
closest to a description is Documentation/filesystems/fiemap.txt
in the kernel tree, but that doesn't document most of the delicate
points.