From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56634) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZaSCx-0008Dh-P8 for qemu-devel@nongnu.org; Fri, 11 Sep 2015 13:33:56 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZaSCw-0000RN-V5 for qemu-devel@nongnu.org; Fri, 11 Sep 2015 13:33:55 -0400 References: <1be64a26c9a89ff0af4c2b1299d6c8b58361644a.1441890725.git.berto@igalia.com> <55F30DA8.4070502@redhat.com> <20150911172854.GC5164@noname.redhat.com> From: Max Reitz Message-ID: <55F31075.7090101@redhat.com> Date: Fri, 11 Sep 2015 19:33:41 +0200 MIME-Version: 1.0 In-Reply-To: <20150911172854.GC5164@noname.redhat.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="oCJH0mqJS3KECIsAShXD19NNrDKKFo3FG" Subject: Re: [Qemu-devel] [PATCH v3 2/4] block: Add 'ignore-backing' field to BlockdevOptionsGenericCOWFormat List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: Stefan Hajnoczi , Alberto Garcia , qemu-devel@nongnu.org, qemu-block@nongnu.org This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --oCJH0mqJS3KECIsAShXD19NNrDKKFo3FG Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable On 11.09.2015 19:28, Kevin Wolf wrote: > Am 11.09.2015 um 19:21 hat Max Reitz geschrieben: >> On 10.09.2015 15:39, Alberto Garcia wrote: >>> If set to true, the image will be opened with the BDRV_O_NO_BACKING >>> flag. This is useful for creating snapshots using images opened with >>> blockdev-add, since they are not supposed to have a backing image >>> before the operation. >>> >>> Signed-off-by: Alberto Garcia >>> --- >>> block.c | 5 +++++ >>> qapi/block-core.json | 6 +++++- >>> 2 files changed, 10 insertions(+), 1 deletion(-) >> >> Ignorant of any possible previous discussion that might have taken >> place: The documentation for @backing says it may be set to the empty >> string in order to achieve exactly that. >> >> So why do we need the new flag? Because "backing: ''" is ugly? >=20 > I guess it's just because you're the only one who actually reads the > documentation. When discussing this, I didn't remember that we already > had a way to express this (an additional bool wouldn't have been my > favourite solution anyway). Thanks for catching this. I read the patch, it was part of the context. ;-) Max --oCJH0mqJS3KECIsAShXD19NNrDKKFo3FG Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJV8xB1AAoJEDuxQgLoOKytdaIH/30ADSMpIajTNS6uCSRv23Ov FEZCQmMnKRrFeUAyolT56uIlaQhQjQn+nTSDwT+saE6J70mYgNm1X9XnKWQURAf/ wEEsZVmzJNxDd9OCHxPchJJ1lnBVT1FujZ8AsHjPlJIVQCYW9wcHGI89qjg78eE6 CYn5til5vlVe3yc5U+vOxtkUc0ydnmkrTcHmWChHp+FycPlV2UYvRD2HPVfn2ukW iwqKb356priC4vWOx+JmQiECpyQrSCN3Wy2TLQer8dYb4f9geBXgVEduzvLcMEaq 0+6hmtdnKWya489K95M+/DOssyOml+zUQvVxEXCg045kpmXYCG0Ryj/HQAS3OTs= =zvcb -----END PGP SIGNATURE----- --oCJH0mqJS3KECIsAShXD19NNrDKKFo3FG--