[PATCH 0/3] Josefs xfs_io patches

[Christoph Hellwig]

I promised to look into adding alias support to libxcmd to allow both
fallocate -p and fpunch to work.  Turns out that isn't quite as easy as I
though.  But given how trivial the hole punching code is I think we can just
put in both version of Josef's patch.  That's what this patchset does - first
one is his fiemap patch, which is unmodified except for the commit message,
and the next two are the fallocate -p and fpunch support, with trivial
changes to provide the FALLOC_FL_PUNCH_HOLE define if the kernel headers
don't provide it.