From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52735) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1b0rjr-0006ZA-Mw for qemu-devel@nongnu.org; Thu, 12 May 2016 10:37:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1b0rjn-0004NB-IP for qemu-devel@nongnu.org; Thu, 12 May 2016 10:37:19 -0400 From: Kevin Wolf Date: Thu, 12 May 2016 16:35:37 +0200 Message-Id: <1463063749-2201-58-git-send-email-kwolf@redhat.com> In-Reply-To: <1463063749-2201-1-git-send-email-kwolf@redhat.com> References: <1463063749-2201-1-git-send-email-kwolf@redhat.com> Subject: [Qemu-devel] [PULL 57/69] 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-block@nongnu.org Cc: kwolf@redhat.com, qemu-devel@nongnu.org From: Wen Congyang 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 Signed-off-by: Changlong Xie Reviewed-by: Max Reitz Reviewed-by: Alberto Garcia Message-id: 1462865799-19402-2-git-send-email-xiecl.fnst@cn.fujitsu.com Signed-off-by: Max Reitz --- block.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++ include/block/block.h | 4 ++++ include/block/block_int.h | 5 +++++ 3 files changed, 58 insertions(+) diff --git a/block.c b/block.c index 724b3b2..0726dab 100644 --- a/block.c +++ b/block.c @@ -4011,3 +4011,52 @@ void bdrv_refresh_filename(BlockDriverState *bs) QDECREF(json); } } + +/* + * 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 does not 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, BdrvChild *child, Error **errp) +{ + BdrvChild *tmp; + + if (!parent_bs->drv || !parent_bs->drv->bdrv_del_child) { + error_setg(errp, "The node %s does not support removing a child", + bdrv_get_device_or_node_name(parent_bs)); + return; + } + + QLIST_FOREACH(tmp, &parent_bs->children, next) { + if (tmp == child) { + break; + } + } + + if (!tmp) { + error_setg(errp, "The node %s does not have a child named %s", + bdrv_get_device_or_node_name(parent_bs), + bdrv_get_device_or_node_name(child->bs)); + return; + } + + parent_bs->drv->bdrv_del_child(parent_bs, child, errp); +} diff --git a/include/block/block.h b/include/block/block.h index 0e8b4d1..c44d0a0 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -542,4 +542,8 @@ void bdrv_drained_begin(BlockDriverState *bs); */ void bdrv_drained_end(BlockDriverState *bs); +void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, + Error **errp); +void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); + #endif diff --git a/include/block/block_int.h b/include/block/block_int.h index 2709488..a029c20 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -314,6 +314,11 @@ struct BlockDriver { */ void (*bdrv_drain)(BlockDriverState *bs); + void (*bdrv_add_child)(BlockDriverState *parent, BlockDriverState *child, + Error **errp); + void (*bdrv_del_child)(BlockDriverState *parent, BdrvChild *child, + Error **errp); + QLIST_ENTRY(BlockDriver) list; }; -- 1.8.3.1