make the bdrv_next_node() clearly and add some comments.
Signed-off-by: Dou Liyang <douly.f...@cn.fujitsu.com>
---
block.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/block.c b/block.c
index 39ddea3..01c9e51 100644
--- a/block.c
+++ b/block.c
@@ -2931,12 +2931,20 @@ bool bdrv_chain_contains(BlockDriverState *top,
BlockDriverState *base)
return top != NULL;
}
+/*
+ * Return the BlockDriverStates of all the named nodes.
+ * If @bs is null, return the first one.
+ * Else, return @bs's next sibling, which may be null.
+ *
+ * To iterate over all BlockDriverStates, do
+ * for (bs = bdrv_next_node(NULL); bs; bs = bdrv_next_node(blk)) {
+ * ...
+ * }
+ */
BlockDriverState *bdrv_next_node(BlockDriverState *bs)
{
- if (!bs) {
- return QTAILQ_FIRST(&graph_bdrv_states);
- }
- return QTAILQ_NEXT(bs, node_list);
+ return bs ? QTAILQ_NEXT(bs, node_list)
+ : QTAILQ_FIRST(&graph_bdrv_states);
}
const char *bdrv_get_node_name(const BlockDriverState *bs)
--
2.5.5
