From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48844) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YNdxB-00005L-3D for qemu-devel@nongnu.org; Tue, 17 Feb 2015 03:56:29 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YNdx7-0006pY-TX for qemu-devel@nongnu.org; Tue, 17 Feb 2015 03:56:25 -0500 Received: from mx2.parallels.com ([199.115.105.18]:39054) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YNdx7-0005x1-M2 for qemu-devel@nongnu.org; Tue, 17 Feb 2015 03:56:21 -0500 Message-ID: <54E301CD.9070806@parallels.com> Date: Tue, 17 Feb 2015 11:54:37 +0300 From: Vladimir Sementsov-Ogievskiy MIME-Version: 1.0 References: <1422356197-5285-1-git-send-email-vsementsov@parallels.com> <1422356197-5285-9-git-send-email-vsementsov@parallels.com> <54DA793C.9020707@redhat.com> <54DDB398.3010907@parallels.com> <54DE5D0F.5080304@redhat.com> <54E1DD49.3050102@parallels.com> <54E23477.9040801@redhat.com> In-Reply-To: <54E23477.9040801@redhat.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH RFC v2 8/8] migration: add migration/dirty-bitmap.c List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: John Snow , qemu-devel@nongnu.org Cc: kwolf@redhat.com, Peter Maydell , "Juan quin >> Juan Jose Quintela Carreira" , "Dr. David Alan Gilbert" , stefanha@redhat.com, den@openvz.org, amit Shah , pbonzini@redhat.com On 16.02.2015 21:18, John Snow wrote: > > > On 02/16/2015 07:06 AM, Vladimir Sementsov-Ogievskiy wrote: >> On 13.02.2015 23:22, John Snow wrote: >>> >>> >>> On 02/13/2015 03:19 AM, Vladimir Sementsov-Ogievskiy wrote: >>>> On 11.02.2015 00:33, John Snow wrote: >>>> So in summary: >>>> using device names is probably fine for now, as it matches the current >>>> use case of bitmaps as well as drive migration; but using node names >>>> may give us more power and precision later. >>>> >>>> I talked to Max about it, and he is leaning towards using device names >>>> for now and switching to node names if we decide we want that power. >>>> >>>> (...I wonder if we could use a flag, for now, that says we're >>>> including DEVICE names. Later, we could add a flag that says we're >>>> using NODE names and add an option to toggle as the usage case sees >>>> fit.) >>>> >>>> >>>> Are you confused yet? :D >> O, thanks for the explanation). Are we really need this flag? As Markus >> wrote, nodes and devices are sharing namespaces.. We can use >> bdrv_lookup_bs(name, name, errp).. > > what 'name' are you using here, though? It looked to me like in your > backup routine we got a list of BDS entries and get the name *from* > the BDS, so we still have to think about how we want to /get/ the name. > >> >> Also, we can, for example, send bitmaps as follows: >> >> if node has name - send bitmap with this name >> if node is root, but hasn't name - send it with blk name >> otherwise - don't send the bitmap > > The node a bitmap is attached to should always have a name -- it would > not be possible via the existing interface to attach it to a node > without a name. > > I *think* the root node should always have a name, but I am actually > less sure of that. > Hmm.. No? bitmap is attached using bdrv_lookup_bs(name, name, errp), which can find device with this name. qemu option -drive file=...,id=disk creates blk named 'disk' and attached node with no name. -- Best regards, Vladimir