Re: obtaining machine frame number

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Sun, Aug 21, 2011 at 06:20:07PM +0300, Eli Cohen wrote:
> Hi list,
> I am trying to allocate a page at a Linux guest and and obtain the
> machine frame number for that page. Then I want to pass the mfn to

OK, use the pci_map_page API - that should give you the MFN
if you are doing this within a PV guest.

> dom0 (I need to use xen store since I have my own mechanism to
> communicate between guests and dom0) and obtain a struct page for it
> (how?) and then dma map it to a pci device. Can some say if/how can

Uh, ..
> this be done?

Why don't you do what the blkback/blkfront is doing. The blkback
is using m2p_add_override to map the local 'struct page' to
that MFN and then that 'struct page' has the guests' MFN
under it.