From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:58648) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VKQtN-0006sZ-KI for qemu-devel@nongnu.org; Fri, 13 Sep 2013 06:46:31 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VKQtI-0000lS-4D for qemu-devel@nongnu.org; Fri, 13 Sep 2013 06:46:25 -0400 Received: from mx.ipv6.kamp.de ([2a02:248:0:51::16]:57995 helo=mx01.kamp.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VKQtH-0000lI-Pv for qemu-devel@nongnu.org; Fri, 13 Sep 2013 06:46:20 -0400 Message-ID: <5232ECFA.5000807@kamp.de> Date: Fri, 13 Sep 2013 12:46:18 +0200 From: Peter Lieven MIME-Version: 1.0 References: <1379067909-22984-1-git-send-email-pl@kamp.de> <1379067909-22984-9-git-send-email-pl@kamp.de> <5232EA90.7030903@redhat.com> In-Reply-To: <5232EA90.7030903@redhat.com> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 08/12] qemu-img: conditionally zero out target on convert List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: kwolf@redhat.com, ronniesahlberg@gmail.com, stefanha@redhat.com, qemu-devel@nongnu.org, anthony@codemonkey.ws On 13.09.2013 12:36, Paolo Bonzini wrote: > Il 13/09/2013 12:25, Peter Lieven ha scritto: >> if the target has_zero_init = 0, but supports efficiently >> writing zeroes by unmapping we call bdrv_zeroize to >> avoid fully allocating the target. this currently >> is designed especially for iscsi. >> >> Signed-off-by: Peter Lieven >> --- >> qemu-img.c | 22 ++++++++++++++++------ >> 1 file changed, 16 insertions(+), 6 deletions(-) >> >> diff --git a/qemu-img.c b/qemu-img.c >> index 3e5e388..6eaddc6 100644 >> --- a/qemu-img.c >> +++ b/qemu-img.c >> @@ -1354,7 +1354,8 @@ static int img_convert(int argc, char **argv) >> } >> } >> >> - flags = BDRV_O_RDWR; >> + flags = BDRV_O_RDWR | BDRV_O_UNMAP; > I think this should be a new command-line flag. In an earlier version there where no objections. I think it would make the usage of qemu-img convert more complicated. For most targets has_zero_init is 1 anyway. Peter