This recent fix isn't quite right: it is causing smaller-than-expected I/Os to
be submitted when extending files, which causes AIO-based writes to oops.

So just revert it - the bug was really over in blockdev_get_blocks() anyway.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>