From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43071) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WztFC-0005j8-LL for qemu-devel@nongnu.org; Wed, 25 Jun 2014 15:52:40 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WztF6-0005nI-Tp for qemu-devel@nongnu.org; Wed, 25 Jun 2014 15:52:34 -0400 Received: from mx1.redhat.com ([209.132.183.28]:27350) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WztF6-0005nC-L9 for qemu-devel@nongnu.org; Wed, 25 Jun 2014 15:52:28 -0400 Message-ID: <53AB2879.8030100@redhat.com> Date: Wed, 25 Jun 2014 13:52:25 -0600 From: Eric Blake MIME-Version: 1.0 References: In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="af6ngSrReA5OAF2llW3JJfmpED7m9Hp8H" Subject: Re: [Qemu-devel] [PATCH v7 for 2.1 4/4] block: add QAPI command to allow live backing file change List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jeff Cody , qemu-devel@nongnu.org Cc: kwolf@redhat.com, benoit.canet@irqsave.net, pkrempa@redhat.com, famz@redhat.com, stefanha@redhat.com This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --af6ngSrReA5OAF2llW3JJfmpED7m9Hp8H Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 06/25/2014 01:40 PM, Jeff Cody wrote: > This allows a user to make a live change to the backing file recorded i= n > an open image. >=20 > The image file to modify can be specified 2 ways: >=20 > 1) image filename > 2) image node-name >=20 > Note: this does not cause the backing file itself to be reopened; it > merely changes the backing filename in the image file structure, and > in internal BDS structures. >=20 > It is the responsibility of the user to pass a filename string that > can be resolved when the image chain is reopened, and the filename > string is not validated. >=20 > A good analogy for this command is that it is a live version of > 'qemu-img rebase -u', with respect to changing the backing file string.= For 2.1, did we want to limit this command to only affecting the active layer (and failing if it was attempted on a backing file), in order to simplify dealing with op-blocker work? Having the command exist, even if it is limited in nature, is all the more libvirt wants right now; and it's easier to relax a constraint in a future release than it is to release something now and have to keep it working even after we rework op-blockers in the future. >=20 > Reviewed-by: Eric Blake > Signed-off-by: Jeff Cody I'm still okay with this patch as-is, if we are okay with the ability to rename the backing file of a non-active node. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --af6ngSrReA5OAF2llW3JJfmpED7m9Hp8H Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJTqyh5AAoJEKeha0olJ0NqTnUH/2r4a8efFr0gEyAPVNLcZI7/ Rr6sW1VIBMiD/6WLIJ44m5in+EUbKrKpRcskF+eDd+veel+l/+oNhZU9AoJbmb/V tTA2SYltdCiY4NCWGQNs6wmGBFtvvME2Kyk83aed52Lg2eflwl1Nug+i4UCwEGFH 2KpV0QiKw0/HmvAPN7BikZqTRnrA/YAoCtnotSkgn7nwxUZ8RRfyZCHbkeW0yyYo J+pvgbVrKMVFpiwtk5s6lLBroa4i7yrWl3BC0qdLaXhLb0ViTQi6kOcmvhwg7q+H RFLIgo1RF8AWt9Unp+m5mZ/Nzs/bj/jxsUSK6y2mG9dYYSSOcGqLELiAgutEc3Q= =Ekpv -----END PGP SIGNATURE----- --af6ngSrReA5OAF2llW3JJfmpED7m9Hp8H--