If the generic code falls back to buffered I/O on a hole XFS needs to
relock, so we need to have separate functions to call unless we want to
duplicate everything.  The XFS patch still needs some cleaning up, but I'll
try to get it in before 2.6.8.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>