jhb 3ca2800ae4 Reduce the number of bounce zones (and thus the number of bounce pages
used in some cases):
- Ignore DMA tag boundaries when allocating bounce pages.  The boundaries
  don't determine whether or not parts of a DMA request bounce.  Instead,
  they are just used to carve up segments.
- Allow tags with sub-page alignment to share bounce pages since bounce
  pages are always page aligned.

Reviewed by:	scottl (amd64)
MFC after:	1 month
2009-04-23 20:24:19 +00:00
..
2009-04-23 00:00:57 +00:00