From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54857) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZaS8B-0005Qm-U8 for qemu-devel@nongnu.org; Fri, 11 Sep 2015 13:29:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZaS8B-00064U-3A for qemu-devel@nongnu.org; Fri, 11 Sep 2015 13:28:59 -0400 Date: Fri, 11 Sep 2015 19:28:54 +0200 From: Kevin Wolf Message-ID: <20150911172854.GC5164@noname.redhat.com> References: <1be64a26c9a89ff0af4c2b1299d6c8b58361644a.1441890725.git.berto@igalia.com> <55F30DA8.4070502@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="0OAP2g/MAC+5xKAE" Content-Disposition: inline In-Reply-To: <55F30DA8.4070502@redhat.com> 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: Max Reitz Cc: Stefan Hajnoczi , Alberto Garcia , qemu-devel@nongnu.org, qemu-block@nongnu.org --0OAP2g/MAC+5xKAE Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable 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. > >=20 > > Signed-off-by: Alberto Garcia > > --- > > block.c | 5 +++++ > > qapi/block-core.json | 6 +++++- > > 2 files changed, 10 insertions(+), 1 deletion(-) >=20 > 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. >=20 > So why do we need the new flag? Because "backing: ''" is ugly? 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. Kevin --0OAP2g/MAC+5xKAE Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIcBAEBAgAGBQJV8w9WAAoJEH8JsnLIjy/W0FwQAKOPSsQ/42wTZ6LToenaOGJE SUi+tPYXkhqD+O4PpumRMTlF2CqiV0WVHuyQRxj0Xg9yMosQTW0A+0O6WN9cRY50 BLDgjFYQ+SEU//+yZmhRjYSU0ziS59jmJb4wUluJUViTvhz++xrBVqbLHYNgrq8t lXRQjPe2QcEKC0i/g4Qcwc3qNDa5eD3UJww9PEsyHuL0PsG6wg8Ch4ii+OBNStDR Jb+Wwqao3JfSRouO4vfyCowteIGnOXkQlORhlwOPZxtdvT35V1Myj/86pbAc6iQ6 THj1zaK21Z13alpta/bBID5htXLfQcKTKuJYsLcuxL4qarBz0KTDCOdhiwsifv3F CigKC7B3qSr/nn1svd6DICudNzWLv8e+yWgfDzJTkSQhA3m7E6kXOu5g9cfiuhJv Sg7m70xv8vJ7HdBd0kpm04F59jOpuFe5+LCbtb7UzAKdysSjB//0L1RgWDFhe3KW qBKb49ANEKNC8Qh4a2+XRCONAr7Tl/s744obns52qq0jVso05vKc0GGbtC3yjkfC bTDbcYu+ji/aNgqICYAAHhUPMmWg9pziC4etzgQf+V8nPmef39zYmMSSReh/QJy2 yn7z1FrRfD/n68m+oR4o+kKrFE8dn7ywbaTZg9CRsQIDjs4uWeBUqdokbNOKKG4L DnkiiX9lfBq2m2SJUrB6 =2lif -----END PGP SIGNATURE----- --0OAP2g/MAC+5xKAE--