svn commit: r196615 - in head/sys: kern sys vm
jhb at freebsd.org
Fri Aug 28 14:24:04 UTC 2009
On Friday 28 August 2009 10:06:56 am John Baldwin wrote:
> Author: jhb
> Date: Fri Aug 28 14:06:55 2009
> New Revision: 196615
> URL: http://svn.freebsd.org/changeset/base/196615
> Extend the device pager to support different memory attributes on different
> pages in an object.
> - Add a new variant of d_mmap() currently called d_mmap2() which accepts
> an additional in/out parameter that is the memory attribute to use for
> the requested page.
> - A driver either uses d_mmap() or d_mmap2() for all requests but not both.
> The current implementation uses a flag in the cdevsw (D_MMAP2) to indicate
> that the driver provides a d_mmap2() handler instead of d_mmap(). This
> is done to make the change ABI compatible with existing drivers and
> MFC'able to 7 and 8.
The future plan for 9.0 is to just convert d_mmap() to the newer API/ABI and
remove d_mmap2(). However, the current version of this patch is MFC'able
without need changes to drivers that do not use the new parameter.
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