Message ID | 1438334355-26914-4-git-send-email-wency@cn.fujitsu.com |
---|---|
State | New |
Headers | show |
On Fri 31 Jul 2015 11:19:12 AM CEST, Wen Congyang wrote: > +/* > + * 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 *bs, QDict *options, Error **errp) > +{ > + > + if (!bs->drv || !bs->drv->bdrv_add_child) { > + error_setg(errp, "The BDS %s doesn't support adding a child", > + bdrv_get_id_or_node_name(bs)); > + return; > + } > + > + bs->drv->bdrv_add_child(bs, options, errp); > +} > + > +void bdrv_del_child(BlockDriverState *bs, BlockDriverState *child_bs, > + Error **errp) > +{ > + BdrvChild *child; > + > + if (!bs->drv || !bs->drv->bdrv_del_child) { > + error_setg(errp, "The BDS %s doesn't support removing a child", > + bdrv_get_id_or_node_name(bs)); > + return; > + } > + > + QLIST_FOREACH(child, &bs->children, next) { > + if (child->bs == child_bs) { > + break; > + } > + } > + > + if (!child) { > + error_setg(errp, "The BDS %s is not the BDS %s's child", > + bdrv_get_id_or_node_name(child_bs), > + bdrv_get_id_or_node_name(bs)); > + return; > + } > + > + bs->drv->bdrv_del_child(bs, child_bs, errp); > +} I see that bdrv_del_child() checks that the child is in bs->children, but who takes care of putting it there in the first place? Berto
On 08/06/2015 10:33 PM, Alberto Garcia wrote: > On Fri 31 Jul 2015 11:19:12 AM CEST, Wen Congyang wrote: > >> +/* >> + * 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 *bs, QDict *options, Error **errp) >> +{ >> + >> + if (!bs->drv || !bs->drv->bdrv_add_child) { >> + error_setg(errp, "The BDS %s doesn't support adding a child", >> + bdrv_get_id_or_node_name(bs)); >> + return; >> + } >> + >> + bs->drv->bdrv_add_child(bs, options, errp); >> +} >> + >> +void bdrv_del_child(BlockDriverState *bs, BlockDriverState *child_bs, >> + Error **errp) >> +{ >> + BdrvChild *child; >> + >> + if (!bs->drv || !bs->drv->bdrv_del_child) { >> + error_setg(errp, "The BDS %s doesn't support removing a child", >> + bdrv_get_id_or_node_name(bs)); >> + return; >> + } >> + >> + QLIST_FOREACH(child, &bs->children, next) { >> + if (child->bs == child_bs) { >> + break; >> + } >> + } >> + >> + if (!child) { >> + error_setg(errp, "The BDS %s is not the BDS %s's child", >> + bdrv_get_id_or_node_name(child_bs), >> + bdrv_get_id_or_node_name(bs)); >> + return; >> + } >> + >> + bs->drv->bdrv_del_child(bs, child_bs, errp); >> +} > > I see that bdrv_del_child() checks that the child is in bs->children, > but who takes care of putting it there in the first place? The child is opened by the function bdrv_open_image(). bdrv_open_image() bdrv_open_child() bdrv_attach_child() Thanks Wen Congyang > > Berto > . >
On Fri 07 Aug 2015 03:03:07 AM CEST, Wen Congyang wrote: >>> +void bdrv_add_child(BlockDriverState *bs, QDict *options, Error **errp) >>> +{ >>> + >>> + if (!bs->drv || !bs->drv->bdrv_add_child) { >>> + error_setg(errp, "The BDS %s doesn't support adding a child", >>> + bdrv_get_id_or_node_name(bs)); >>> + return; >>> + } >>> + >>> + bs->drv->bdrv_add_child(bs, options, errp); >>> +} >>> + >>> +void bdrv_del_child(BlockDriverState *bs, BlockDriverState *child_bs, >>> + Error **errp) >>> +{ >>> + BdrvChild *child; >>> + >>> + if (!bs->drv || !bs->drv->bdrv_del_child) { >>> + error_setg(errp, "The BDS %s doesn't support removing a child", >>> + bdrv_get_id_or_node_name(bs)); >>> + return; >>> + } >>> + >>> + QLIST_FOREACH(child, &bs->children, next) { >>> + if (child->bs == child_bs) { >>> + break; >>> + } >>> + } >>> + >>> + if (!child) { >>> + error_setg(errp, "The BDS %s is not the BDS %s's child", >>> + bdrv_get_id_or_node_name(child_bs), >>> + bdrv_get_id_or_node_name(bs)); >>> + return; >>> + } >>> + >>> + bs->drv->bdrv_del_child(bs, child_bs, errp); >>> +} >> >> I see that bdrv_del_child() checks that the child is in bs->children, >> but who takes care of putting it there in the first place? > > The child is opened by the function bdrv_open_image(). > bdrv_open_image() > bdrv_open_child() > bdrv_attach_child() I see, it's drv->bdrv_add_child() who takes care of opening the image, this only provides the BlockdevOptions. Thanks! Reviewed-by: Alberto Garcia <berto@igalia.com> Berto
On Fri 31 Jul 2015 11:19:12 AM CEST, Wen Congyang wrote: > +static const char *bdrv_get_id_or_node_name(BlockDriverState *bs) > +{ > + if (bs->blk) { > + return blk_name(bs->blk); > + } > + > + return bs->node_name ? bs->node_name : ""; > +} You don't need to add this function, you can use bdrv_get_device_or_node_name() instead. Berto
On 08/10/2015 04:19 PM, Alberto Garcia wrote: > On Fri 31 Jul 2015 11:19:12 AM CEST, Wen Congyang wrote: > >> +static const char *bdrv_get_id_or_node_name(BlockDriverState *bs) >> +{ >> + if (bs->blk) { >> + return blk_name(bs->blk); >> + } >> + >> + return bs->node_name ? bs->node_name : ""; >> +} > > You don't need to add this function, you can use > bdrv_get_device_or_node_name() instead. Yes, I will update it in the next version. Thanks Wen Congyang > > Berto > . >
diff --git a/block.c b/block.c index d088ee0..934a32d 100644 --- a/block.c +++ b/block.c @@ -4251,3 +4251,55 @@ BlockAcctStats *bdrv_get_stats(BlockDriverState *bs) { return &bs->stats; } + +static const char *bdrv_get_id_or_node_name(BlockDriverState *bs) +{ + if (bs->blk) { + return blk_name(bs->blk); + } + + return bs->node_name ? bs->node_name : ""; +} + +/* + * 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 *bs, QDict *options, Error **errp) +{ + + if (!bs->drv || !bs->drv->bdrv_add_child) { + error_setg(errp, "The BDS %s doesn't support adding a child", + bdrv_get_id_or_node_name(bs)); + return; + } + + bs->drv->bdrv_add_child(bs, options, errp); +} + +void bdrv_del_child(BlockDriverState *bs, BlockDriverState *child_bs, + Error **errp) +{ + BdrvChild *child; + + if (!bs->drv || !bs->drv->bdrv_del_child) { + error_setg(errp, "The BDS %s doesn't support removing a child", + bdrv_get_id_or_node_name(bs)); + return; + } + + QLIST_FOREACH(child, &bs->children, next) { + if (child->bs == child_bs) { + break; + } + } + + if (!child) { + error_setg(errp, "The BDS %s is not the BDS %s's child", + bdrv_get_id_or_node_name(child_bs), + bdrv_get_id_or_node_name(bs)); + return; + } + + bs->drv->bdrv_del_child(bs, child_bs, errp); +} diff --git a/include/block/block.h b/include/block/block.h index 37916f7..4a03fb6 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -616,4 +616,8 @@ void bdrv_flush_io_queue(BlockDriverState *bs); BlockAcctStats *bdrv_get_stats(BlockDriverState *bs); +void bdrv_add_child(BlockDriverState *bs, QDict *options, Error **errp); +void bdrv_del_child(BlockDriverState *bs, BlockDriverState *child, + Error **errp); + #endif diff --git a/include/block/block_int.h b/include/block/block_int.h index 14ad4c3..b6f2905 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); + void (*bdrv_add_child)(BlockDriverState *bs, QDict *options, + Error **errp); + void (*bdrv_del_child)(BlockDriverState *bs, BlockDriverState *child, + Error **errp); + QLIST_ENTRY(BlockDriver) list; };