From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50907) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZjtWi-00067V-KE for qemu-devel@nongnu.org; Wed, 07 Oct 2015 14:33:21 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZjtWh-0002gY-LP for qemu-devel@nongnu.org; Wed, 07 Oct 2015 14:33:20 -0400 References: <1442907862-21376-1-git-send-email-wency@cn.fujitsu.com> <1442907862-21376-2-git-send-email-wency@cn.fujitsu.com> From: Max Reitz Message-ID: <56156562.6000909@redhat.com> Date: Wed, 7 Oct 2015 20:33:06 +0200 MIME-Version: 1.0 In-Reply-To: <1442907862-21376-2-git-send-email-wency@cn.fujitsu.com> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="C8oKUAkkP5RfQ0InlnqEdRglB68NxI4n4" Subject: Re: [Qemu-devel] [Qemu-block] [PATCH v5 1/4] Add new block driver interface to add/delete a BDS's child List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Wen Congyang , qemu devel , Eric Blake , Markus Armbruster , Alberto Garcia , Stefan Hajnoczi Cc: Kevin Wolf , zhanghailiang , qemu block , Jiang Yunhong , Dong Eddie , "Dr. David Alan Gilbert" , Gonglei , Yang Hongyang This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --C8oKUAkkP5RfQ0InlnqEdRglB68NxI4n4 Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: quoted-printable On 22.09.2015 09:44, Wen Congyang wrote: > In some cases, we want to take a quorum child offline, and take > another child online. >=20 > Signed-off-by: Wen Congyang > Signed-off-by: zhanghailiang > Signed-off-by: Gonglei > Reviewed-by: Eric Blake > --- > block.c | 50 +++++++++++++++++++++++++++++++++++++++= ++++++++ > include/block/block.h | 5 +++++ > include/block/block_int.h | 5 +++++ > 3 files changed, 60 insertions(+) >=20 > diff --git a/block.c b/block.c > index e815d73..1b25e43 100644 > --- a/block.c > +++ b/block.c > @@ -4265,3 +4265,53 @@ BlockAcctStats *bdrv_get_stats(BlockDriverState = *bs) > { > return &bs->stats; > } > + > +/* > + * Hot add/remove a BDS's child. So the user can take a child offline = when > + * it is broken and take a new child online > + */ > +void bdrv_add_child(BlockDriverState *parent_bs, BlockDriverState *chi= ld_bs, > + Error **errp) > +{ > + > + if (!parent_bs->drv || !parent_bs->drv->bdrv_add_child) { > + error_setg(errp, "The BDS %s doesn't support adding a child", > + bdrv_get_device_or_node_name(parent_bs)); > + return; > + } > + > + if (!QLIST_EMPTY(&child_bs->parents)) { > + error_setg(errp, "The BDS %s already has parent", > + child_bs->node_name); > + return; > + } > + > + parent_bs->drv->bdrv_add_child(parent_bs, child_bs, errp); > +} > + > +void bdrv_del_child(BlockDriverState *parent_bs, BlockDriverState *chi= ld_bs, > + Error **errp) > +{ > + BdrvChild *child; > + > + if (!parent_bs->drv || !parent_bs->drv->bdrv_del_child) { > + error_setg(errp, "The BDS %s doesn't support removing a child"= , > + bdrv_get_device_or_node_name(parent_bs)); > + return; > + } > + > + QLIST_FOREACH(child, &parent_bs->children, next) { > + if (child->bs =3D=3D child_bs) { > + break; > + } > + } > + > + if (!child) { > + error_setg(errp, "BDS %s is not a child of %s", > + bdrv_get_device_or_node_name(child_bs), > + bdrv_get_device_or_node_name(parent_bs)); > + return; > + } > + > + parent_bs->drv->bdrv_del_child(parent_bs, child_bs, errp); How about we make this (BlockDriver.bdrv_del_child()) take a BdrvChild instead of a BDS? We could even make bdrv_del_child() as a whole take a BdrvChild parameter, but I don't suppose that would help much. Max > +} > diff --git a/include/block/block.h b/include/block/block.h > index ef67353..665c56f 100644 > --- a/include/block/block.h > +++ b/include/block/block.h > @@ -616,4 +616,9 @@ void bdrv_flush_io_queue(BlockDriverState *bs); > =20 > BlockAcctStats *bdrv_get_stats(BlockDriverState *bs); > =20 > +void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child,= > + Error **errp); > +void bdrv_del_child(BlockDriverState *parent, BlockDriverState *child,= > + Error **errp); > + > #endif > diff --git a/include/block/block_int.h b/include/block/block_int.h > index 2f2c47b..64cbc55 100644 > --- a/include/block/block_int.h > +++ b/include/block/block_int.h > @@ -288,6 +288,11 @@ struct BlockDriver { > */ > int (*bdrv_probe_geometry)(BlockDriverState *bs, HDGeometry *geo);= > =20 > + void (*bdrv_add_child)(BlockDriverState *parent, BlockDriverState = *child, > + Error **errp); > + void (*bdrv_del_child)(BlockDriverState *parent, BlockDriverState = *child, > + Error **errp); > + > QLIST_ENTRY(BlockDriver) list; > }; > =20 >=20 --C8oKUAkkP5RfQ0InlnqEdRglB68NxI4n4 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 iQEcBAEBCAAGBQJWFWViAAoJEDuxQgLoOKyt5rEH/0pF1NqsOQQeqNWgXE46wJgI K4gNPQHHOMc4bmfze+pblapsGgCzwgJkUmsL2brZzeLMA4s5zivDC5gxepZpGAJ5 sJjis2LyAEz+aQNp2XVLT94Tp/jYreUTBXVp+SpZdmsEtzcRo51uBL5i1nnH4mUR pmuSUfcP9KKnXRTOK0iVJ6FunG3pBuQ66YspeskTz0V3k729DotaBi2T9zhU1czy O6N823OsgpjteFdktizdUCHIn20RyurP0j6NNKvy1mOTEzpzRvOlcHcrEwUWIMtA svOZX2u5qhCoc13KGpyXBZEqX97LNzl7vZe/AGYlu+hbEqkbCVGRPmaimKh7Uog= =3zcr -----END PGP SIGNATURE----- --C8oKUAkkP5RfQ0InlnqEdRglB68NxI4n4--