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RE: [Xen-devel] question on get_page_and_type()

To: "Santos, Jose Renato G" <joserenato.santos@xxxxxx>, <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: RE: [Xen-devel] question on get_page_and_type()
From: "Ian Pratt" <Ian.Pratt@xxxxxxxxxxxx>
Date: Sat, 14 Apr 2007 04:15:10 +0100
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Thread-topic: [Xen-devel] question on get_page_and_type()
> Could someone please explain the following
> What is the purpose of get_page_and_type(page, domain,
> PGT_writable_page) and why is it needed when doing a grant copy in
> __gnttab_copy()?
> Why can't we just use get_page() to prevent the page from being freed
> while we are doing the copy?

You don't want guests receiving data into pages containing pagetables,
hence we make sure we can get the page as a writeable page.

Ian
 

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