From mboxrd@z Thu Jan 1 00:00:00 1970 From: Markus Armbruster Subject: Re: Re: userspace block backend / gntdev problems Date: Sat, 26 Jan 2008 09:41:25 +0100 Message-ID: <8763xhf07e.fsf@pike.pond.sub.org> References: <477E3925.7070404@redhat.com> <1D19FC42-377A-47C7-8B6F-5BD56284C117@cl.cam.ac.uk> <87zluzowc7.fsf@pike.pond.sub.org> <479A70F7.7080405@novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: In-Reply-To: <479A70F7.7080405@novell.com> (Pat Campbell's message of "Fri\, 25 Jan 2008 16\:29\:59 -0700") List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Pat Campbell Cc: Derek Murray , Xen Development Mailing List , Gerd Hoffmann List-Id: xen-devel@lists.xenproject.org Pat Campbell writes: [...] > In my latest post on "Dynamic modes support for PV xenfb" I am using > grants to map an extended framebuffer. I have a single grant ref that > points to 10 other refs. The other refs contain MFNs. Same technique as > the current framebuffer pd array but avoids the 64bit long issue. Kind > of a hybrid approach. I am able to map a 22MB framebuffer when running a > 64 bit guest and 44MB when running a 32 bit guest. When the backend is > done with the mapping it sends a message to the frontend to free up the > refs. Uhm, I fear I didn't get the advantage of your hybrid approach. Could you explain? > I did try to map the whole framebuffers via grants, failed. Like you say > you need a whole bunch of them.