Re: [PATCH] SN2 user-MMIO CPU migration

Brent Casavant
2006-01-24T16:52:38Z

On Mon, 23 Jan 2006, Grant Grundler wrote:

> On Tue, Jan 24, 2006 at 12:30:42AM -0600, Brent Casavant wrote:
> > The only obvious marker I can thing of would be a flag in the
> > mm struct set by a device driver when such a mapping occurs.
>
> Device driver? Your original email only talks about user space:
> http://marc.theaimsgroup.com/?l=linux-ia64&m\x113771591308925&w=2

Right. But the whole situation occurs when user space mmap()s
an IO device (e.g. a PCI aperture). That mmap() call triggers
kernel device driver mmap code to take place, and that is where
the flag would need to be set.

Sorry I wasn't clear about that.

Brent

--
Brent Casavant All music is folk music. I ain't
bcasavan@sgi.com never heard a horse sing a song.
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