From mboxrd@z Thu Jan 1 00:00:00 1970 From: Avi Kivity Subject: Re: Userspace MSR handling Date: Sun, 31 May 2009 11:21:18 +0300 Message-ID: <4A223DFE.5040603@redhat.com> References: <9ae48b020905221311h1859d5a1v3653404721d5208b@mail.gmail.com> <790CB8FA-1660-4F6B-BEEC-AAB9724DDD64@suse.de> <4A193878.4030206@redhat.com> <4A1A7B14.5000205@redhat.com> <4A1A7F03.1020106@redhat.com> <9ae48b020905270912ib832446q28c47ebaf0da1720@mail.gmail.com> <4A1D6A1D.2040400@redhat.com> <9ae48b020905271009k4e3b646bva958f78516e69122@mail.gmail.com> <4A1D9191.1070600@redhat.com> <4A1E5108.5080307@redhat.com> <4A1FAF3A.8040302@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Ed Swierk , Alexander Graf , "kvm@vger.kernel.org" To: Gerd Hoffmann Return-path: Received: from mx2.redhat.com ([66.187.237.31]:54226 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753109AbZEaIVW (ORCPT ); Sun, 31 May 2009 04:21:22 -0400 In-Reply-To: <4A1FAF3A.8040302@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: Gerd Hoffmann wrote: >> >> Or do the standard function pointer trick. Event channel notifications >> change to eventfd_signal, grant table ops change to copy_to_user(). > > grant table ops include mapping pages of the guest (aka domU) into the > host (aka dom0) address space, fill the pointer into some struct (bio > for blkback, skb for netback), send it down the road for processing. > netback and blkback do quite some lowlevel xen memory management to > get that done, including m2p and p2m table updates due to direct > paging mode. It isn't as easy as s/hypercall/get_user_pages/ ... So we need to plug it at a slightly higher level. Conceptually can provide the same interfaces as xen, so it's just a matter of abstracting it nicely. -- error compiling committee.c: too many arguments to function