From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53492) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zn0q1-0007uQ-V3 for qemu-devel@nongnu.org; Fri, 16 Oct 2015 04:58:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Zn0q0-0002s7-Nv for qemu-devel@nongnu.org; Fri, 16 Oct 2015 04:58:09 -0400 From: Wen Congyang Date: Fri, 16 Oct 2015 16:57:43 +0800 Message-ID: <1444985866-12969-2-git-send-email-wency@cn.fujitsu.com> In-Reply-To: <1444985866-12969-1-git-send-email-wency@cn.fujitsu.com> References: <1444985866-12969-1-git-send-email-wency@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain Subject: [Qemu-devel] [PATCH v6 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: qemu devel , Eric Blake , Markus Armbruster , Alberto Garcia , Kevin Wolf , Stefan Hajnoczi Cc: qemu block , Jiang Yunhong , Dong Eddie , "Dr. David Alan Gilbert" , Gonglei , Yang Hongyang , zhanghailiang In some cases, we want to take a quorum child offline, and take another child online. 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(+) diff --git a/block.c b/block.c index 62848ca..bcba22f 100644 --- a/block.c +++ b/block.c @@ -4183,3 +4183,53 @@ 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 *child_bs, + Error **errp) +{ + + if (!parent_bs->drv || !parent_bs->drv->bdrv_add_child) { + error_setg(errp, "The node %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 node %s already has a 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 *child_bs, + Error **errp) +{ + BdrvChild *child; + + if (!parent_bs->drv || !parent_bs->drv->bdrv_del_child) { + error_setg(errp, "The node %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 == child_bs) { + break; + } + } + + if (!child) { + error_setg(errp, "The node %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); +} diff --git a/include/block/block.h b/include/block/block.h index 1520dee..ef84c87 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -624,4 +624,9 @@ void bdrv_flush_io_queue(BlockDriverState *bs); BlockAcctStats *bdrv_get_stats(BlockDriverState *bs); +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 c0e6513..cd66223 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -287,6 +287,11 @@ struct BlockDriver { */ int (*bdrv_probe_geometry)(BlockDriverState *bs, HDGeometry *geo); + void (*bdrv_add_child)(BlockDriverState *parent, BlockDriverState *child, + Error **errp); + void (*bdrv_del_child)(BlockDriverState *parent, BlockDriverState *child, + Error **errp); + QLIST_ENTRY(BlockDriver) list; }; -- 2.4.3