From 810803a87ce88abd695f07f434d00e7cd1e122e2 Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Tue, 18 Feb 2020 11:34:44 +0100 Subject: block: Use bdrv_recurse_can_replace() Let check_to_replace_node() use the more specialized bdrv_recurse_can_replace() instead of bdrv_recurse_is_first_non_filter(), which is too restrictive (or, in the case of quorum, sometimes not restrictive enough). Signed-off-by: Max Reitz Reviewed-by: Vladimir Sementsov-Ogievskiy Message-Id: <20200218103454.296704-10-mreitz@redhat.com> Signed-off-by: Kevin Wolf --- block.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) (limited to 'block.c') diff --git a/block.c b/block.c index e2fefe5883..80a0806eb0 100644 --- a/block.c +++ b/block.c @@ -6272,6 +6272,17 @@ bool bdrv_recurse_can_replace(BlockDriverState *bs, return false; } +/* + * Check whether the given @node_name can be replaced by a node that + * has the same data as @parent_bs. If so, return @node_name's BDS; + * NULL otherwise. + * + * @node_name must be a (recursive) *child of @parent_bs (or this + * function will return NULL). + * + * The result (whether the node can be replaced or not) is only valid + * for as long as no graph or permission changes occur. + */ BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, const char *node_name, Error **errp) { @@ -6296,8 +6307,11 @@ BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, * Another benefit is that this tests exclude backing files which are * blocked by the backing blockers. */ - if (!bdrv_recurse_is_first_non_filter(parent_bs, to_replace_bs)) { - error_setg(errp, "Only top most non filter can be replaced"); + if (!bdrv_recurse_can_replace(parent_bs, to_replace_bs)) { + error_setg(errp, "Cannot replace '%s' by a node mirrored from '%s', " + "because it cannot be guaranteed that doing so would not " + "lead to an abrupt change of visible data", + node_name, parent_bs->node_name); to_replace_bs = NULL; goto out; } -- cgit v1.2.3