From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51003) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1an7YM-000159-FN for qemu-devel@nongnu.org; Mon, 04 Apr 2016 12:40:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1an7YI-0001vs-0P for qemu-devel@nongnu.org; Mon, 04 Apr 2016 12:40:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37198) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1an7YH-0001vm-Py for qemu-devel@nongnu.org; Mon, 04 Apr 2016 12:40:33 -0400 References: <1458742562-30624-1-git-send-email-den@openvz.org> <1458742562-30624-3-git-send-email-den@openvz.org> From: Eric Blake Message-ID: <570298FE.8090501@redhat.com> Date: Mon, 4 Apr 2016 10:40:30 -0600 MIME-Version: 1.0 In-Reply-To: <1458742562-30624-3-git-send-email-den@openvz.org> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="a5fCQNuKi6v5dBLUsVTsPReagx6DC0uGN" Subject: Re: [Qemu-devel] [PATCH 2/2] NBD proto: add GET_LBA_STATUS extension List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Denis V. Lunev" , nbd-general@lists.sourceforge.net, qemu-devel@nongnu.org Cc: Kevin Wolf , Paolo Bonzini , Pavel Borzenkov , Stefan Hajnoczi , Wouter Verhelst This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --a5fCQNuKi6v5dBLUsVTsPReagx6DC0uGN Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On 03/23/2016 08:16 AM, Denis V. Lunev wrote: > From: Pavel Borzenkov >=20 > With the availability of sparse storage formats, it is often needed to > query status of a particular LBA range and read only those blocks of > data that are actually present on the block device. >=20 > To provide such information, the patch adds GET_LBA_STATUS extension > with one new NBD_CMD_GET_LBA_STATUS command. >=20 > There exists a concept of data dirtiness, which is required during, for= > example, incremental block device backup. To express this concept via > NBD protocol, this patch also adds additional mode of operation to > NBD_CMD_GET_LBA_STATUS command. >=20 > Since NBD protocol has no notion of block size, and to mimic SCSI "GET > LBA STATUS" command more closely, it has been chosen to return a list o= f > extents in the response of NBD_CMD_GET_LBA_STATUS command, instead of a= > bitmap. >=20 > Signed-off-by: Pavel Borzenkov > Reviewed-by: Roman Kagan > Signed-off-by: Denis V. Lunev > CC: Wouter Verhelst > CC: Paolo Bonzini > CC: Kevin Wolf > CC: Stefan Hajnoczi > --- > doc/proto.md | 82 ++++++++++++++++++++++++++++++++++++++++++++++++++++= ++++++++ > 1 file changed, 82 insertions(+) I've posted a v2 of this proposal under a new title, rebased on top of the recent work to add structured replies, and trying to take into account a number of the suggestions that occurred in this thread. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --a5fCQNuKi6v5dBLUsVTsPReagx6DC0uGN 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 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJXApj+AAoJEKeha0olJ0NqPu8IAJX2SOFeCw/7233niJKCqx9X L2H2Zq87R+XYV+zWV1RPiFozuX+6t93dtl2kmsH69o3sKHc+A8i/sjWeQK64U/pe za+f5gpVVGidSsEpyl6N4s03ET5jC+N00mEynvRTMkGWZMj8knQ/rAMXzwVgkbLg bXhlTWgLQLWpU96y/VtjJVwH6zpGSZ3F5SyAGDxPFa60+6LwA3xKZD4PY9tlwD/e /aSg+AkB+ePu9aU6lcYGnMhokBEqGMUg917rtwZkUVrIlQTLc4/bY/TqQA2A5+Ki NcyoK38WH2ZO7edG9TSg2pdgolJPRpgcd2TRjpKp0TWh7BZdX/tefLIw3OJgG6o= =mUjh -----END PGP SIGNATURE----- --a5fCQNuKi6v5dBLUsVTsPReagx6DC0uGN--