sf_buf_alloc()/sf_buf_free() inlines, to save two calls to an absolutely
empty functions.
Reviewed by: alc, kib, scottl
Sponsored by: Nginx, Inc.
Sponsored by: Netflix
distinguish between UC and WB memory so that we can map the page to
either a region 6 address (for UC) or a region 7 address (for WB).
This change is only now possible, because previously we would map
regions 6 and 7 with 256MB translations and on top of that had the
kernel mapped in region 7 using a wired translation. The introduction
of the PBVM moved the kernel into its own region and freed up region
7 and allowed us to revert to standard page-sized translations.
This commit inroduces pmap_page_to_va() that respects the attribute.
physical mapping.
- Move the sf_buf API to its own header file; make struct sf_buf's
definition machine dependent. In this commit, we remove an
unnecessary field from struct sf_buf on the alpha, amd64, and ia64.
Ultimately, we may eliminate struct sf_buf on those architecures
except as an opaque pointer that references a vm page.
