From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:56896) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1UepiC-00080h-UH for qemu-devel@nongnu.org; Tue, 21 May 2013 12:47:02 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Uepi7-0005WD-LE for qemu-devel@nongnu.org; Tue, 21 May 2013 12:46:56 -0400 Received: from mx1.redhat.com ([209.132.183.28]:61505) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Uepi7-0005W0-Cy for qemu-devel@nongnu.org; Tue, 21 May 2013 12:46:51 -0400 Message-ID: <519BA4EF.1000302@redhat.com> Date: Tue, 21 May 2013 18:46:39 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1368628476-19622-1-git-send-email-stefanha@redhat.com> <1368628476-19622-3-git-send-email-stefanha@redhat.com> <519A095D.4070808@redhat.com> <20130521133428.GA6631@stefanha-thinkpad.muc.redhat.com> <519B8EBD.6030006@redhat.com> <24E144B8C0207547AD09C467A8259F7558598A21@lisa.maurer-it.com> In-Reply-To: <24E144B8C0207547AD09C467A8259F7558598A21@lisa.maurer-it.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v3 2/8] block: add basic backup support to block driver List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Dietmar Maurer Cc: Kevin Wolf , Fam Zheng , Stefan Hajnoczi , "qemu-devel@nongnu.org" , "imain@redhat.com" , Stefan Hajnoczi , "xiawenc@linux.vnet.ibm.com" Il 21/05/2013 18:26, Dietmar Maurer ha scritto: >> Hmm, right. But do we need the bitmap at all? We can just use >> > bdrv_is_allocated like bdrv_co_do_readv does. > Does that works with a nbd driver? Ah, right. That's the answer. > Or does that add another RPC call (slow down)? It doesn't work at all. Thus Stefan's patch is fine (except if you don't use HBitmapIter, there's no advantage in using HBitmap; you can use qemu/bitmap.h instead). Paolo