net: dsa: move dsa_tree_notify() and dsa_broadcast() to switch.c

There isn't an intuitive place for these 2 cross-chip notifier functions
according to the function-to-file classification based on names
(dsa_switch_*() goes to switch.c), but I consider these to be part of
the cross-chip notifier handling, therefore part of switch.c. Move them
there to reduce bloat in dsa2.c (the place where all code with no better
place to go goes).

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 46 insertions, 0 deletions

diff --git a/net/dsa/switch.c b/net/dsa/switch.c
index 6a1c84c5ec8b..b534116dc519 100644
--- a/net/dsa/switch.c
+++ b/net/dsa/switch.c
@@ -1016,6 +1016,52 @@ static int dsa_switch_event(struct notifier_block *nb,
 	return notifier_from_errno(err);
 }
 
+/**
+ * dsa_tree_notify - Execute code for all switches in a DSA switch tree.
+ * @dst: collection of struct dsa_switch devices to notify.
+ * @e: event, must be of type DSA_NOTIFIER_*
+ * @v: event-specific value.
+ *
+ * Given a struct dsa_switch_tree, this can be used to run a function once for
+ * each member DSA switch. The other alternative of traversing the tree is only
+ * through its ports list, which does not uniquely list the switches.
+ */
+int dsa_tree_notify(struct dsa_switch_tree *dst, unsigned long e, void *v)
+{
+	struct raw_notifier_head *nh = &dst->nh;
+	int err;
+
+	err = raw_notifier_call_chain(nh, e, v);
+
+	return notifier_to_errno(err);
+}
+
+/**
+ * dsa_broadcast - Notify all DSA trees in the system.
+ * @e: event, must be of type DSA_NOTIFIER_*
+ * @v: event-specific value.
+ *
+ * Can be used to notify the switching fabric of events such as cross-chip
+ * bridging between disjoint trees (such as islands of tagger-compatible
+ * switches bridged by an incompatible middle switch).
+ *
+ * WARNING: this function is not reliable during probe time, because probing
+ * between trees is asynchronous and not all DSA trees might have probed.
+ */
+int dsa_broadcast(unsigned long e, void *v)
+{
+	struct dsa_switch_tree *dst;
+	int err = 0;
+
+	list_for_each_entry(dst, &dsa_tree_list, list) {
+		err = dsa_tree_notify(dst, e, v);
+		if (err)
+			break;
+	}
+
+	return err;
+}
+
 int dsa_switch_register_notifier(struct dsa_switch *ds)
 {
 	ds->nb.notifier_call = dsa_switch_event;