git and linux kernel source

A few linux kernel source and git questions:

What's the best procedure to handle a tree-wide source tranformation? For instance:

  git branch foo2bar
  egrep -r -w --include=*.[ch] -l "foo" * | \
	xargs perl -pi -e 's/\bfoo\b/bar/msg'
  git commit -a -m "use bar not foo"

Is there a way to separate the resultant single patch into multiple patches by subdirectory? Perhaps some git-rev-parse option?

  git-format-patch -p --stat -o outputdir

Is there a way to automatically include the appropriate MAINTAINER and mailing lists from the MAINTAINERS file for each subdirectory?

  git-send-mail --to $APPROPRIATE_MAINTAINER \
	-cc linux-kernel@vger.kernel.org

Any ideas or help?