[PATCH] docs: admin-guide/blockdev: Use subgraphs in node-states-8.dot

[Akira Yokosawa]

While node-states-8.dot has two digraphs, dot(1) command can not
properly handle multiple graphs in a DOT file.

Use subgraphs and merge them into a single graph.

Signed-off-by: Akira Yokosawa <akiyks@xxxxxxxxx>
Cc: Philipp Reisner <philipp.reisner@xxxxxxxxxx>
Cc: Lars Ellenberg <lars.ellenberg@xxxxxxxxxx>
---
Hi Jon,

I happened to spot a broken DOT script at the bottom of

    https://www.kernel.org/doc/html/latest/admin-guide/blockdev/drbd/figures.html

and managed to fix it.

DRBD DRIVER maintainers,
If I'm missing something here, please let me know.

        Thanks, Akira
--
 .../blockdev/drbd/node-states-8.dot           | 25 +++++++++++--------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/Documentation/admin-guide/blockdev/drbd/node-states-8.dot b/Documentation/admin-guide/blockdev/drbd/node-states-8.dot
index bfa54e1f8016..993f0c152ead 100644
--- a/Documentation/admin-guide/blockdev/drbd/node-states-8.dot
+++ b/Documentation/admin-guide/blockdev/drbd/node-states-8.dot
@@ -1,13 +1,16 @@
-digraph node_states {
-	Secondary -> Primary           [ label = "ioctl_set_state()" ]
-	Primary   -> Secondary 	       [ label = "ioctl_set_state()" ]
-}
+digraph G {
+	compound=true;
+	subgraph node_states {
+		Secondary -> Primary           [ label = "ioctl_set_state()" ]
+		Primary   -> Secondary 	       [ label = "ioctl_set_state()" ]
+	}
 
-digraph peer_states {
-	Secondary -> Primary           [ label = "recv state packet" ]
-	Primary   -> Secondary 	       [ label = "recv state packet" ]
-	Primary   -> Unknown 	       [ label = "connection lost" ]
-	Secondary  -> Unknown  	       [ label = "connection lost" ]
-	Unknown   -> Primary           [ label = "connected" ]
-	Unknown   -> Secondary         [ label = "connected" ]
+	subgraph peer_states {
+		Secondary -> Primary           [ label = "recv state packet" ]
+		Primary   -> Secondary 	       [ label = "recv state packet" ]
+		Primary   -> Unknown 	       [ label = "connection lost" ]
+		Secondary  -> Unknown  	       [ label = "connection lost" ]
+		Unknown   -> Primary           [ label = "connected" ]
+		Unknown   -> Secondary         [ label = "connected" ]
+	}
 }

base-commit: 53b606fa29e321352a105978726b975b42b292a4
-- 
2.17.1