[PATCH net-next 6/6] net: dsa: introduce bridge notifier

From: Vivien Didelot
Date: Fri Feb 03 2017 - 13:23:30 EST


A slave device will now notify the switch fabric once its port is
bridged or unbridged, instead of calling directly its switch operations.

This code allows propagating cross-chip bridging events in the fabric.

Signed-off-by: Vivien Didelot <vivien.didelot@xxxxxxxxxxxxxxxxxxxx>
---
include/net/dsa.h | 10 ++++++++++
net/dsa/slave.c | 40 +++++++++++++++++++++++++++++-----------
net/dsa/switch.c | 32 ++++++++++++++++++++++++++++++++
3 files changed, 71 insertions(+), 11 deletions(-)

diff --git a/include/net/dsa.h b/include/net/dsa.h
index ac4ea7c3a102..e9c940c8936f 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -268,6 +268,16 @@ struct switchdev_obj_port_fdb;
struct switchdev_obj_port_mdb;
struct switchdev_obj_port_vlan;

+#define DSA_NOTIFIER_BRIDGE_JOIN 1
+#define DSA_NOTIFIER_BRIDGE_LEAVE 2
+
+/* DSA_NOTIFIER_BRIDGE_* */
+struct dsa_notifier_bridge_info {
+ struct net_device *br;
+ int sw_index;
+ int port;
+};
+
struct dsa_switch_ops {
/*
* Probing and setup.
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index d8c3c0f00cf3..061a49c29cef 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -27,6 +27,17 @@

static bool dsa_slave_dev_check(struct net_device *dev);

+static int dsa_slave_notify(struct net_device *dev, unsigned long e, void *v)
+{
+ struct dsa_slave_priv *p = netdev_priv(dev);
+ struct raw_notifier_head *nh = &p->dp->ds->dst->nh;
+ int err;
+
+ err = raw_notifier_call_chain(nh, e, v);
+
+ return notifier_to_errno(err);
+}
+
/* slave mii_bus handling ***************************************************/
static int dsa_slave_phy_read(struct mii_bus *bus, int addr, int reg)
{
@@ -562,39 +573,46 @@ static int dsa_slave_bridge_port_join(struct net_device *dev,
struct net_device *br)
{
struct dsa_slave_priv *p = netdev_priv(dev);
- struct dsa_switch *ds = p->dp->ds;
- int ret = -EOPNOTSUPP;
+ struct dsa_notifier_bridge_info info = {
+ .sw_index = p->dp->ds->index,
+ .port = p->dp->index,
+ .br = br,
+ };
+ int err;

/* Here the port is already bridged. Reflect the current configuration
* so that drivers can program their chips accordingly.
*/
p->dp->bridge_dev = br;

- if (ds->ops->port_bridge_join)
- ret = ds->ops->port_bridge_join(ds, p->dp->index, br);
+ err = dsa_slave_notify(dev, DSA_NOTIFIER_BRIDGE_JOIN, &info);

/* The bridging is rolled back on error */
- if (ret && ret != -EOPNOTSUPP) {
+ if (err)
p->dp->bridge_dev = NULL;
- return ret;
- }

- return 0;
+ return err;
}

static void dsa_slave_bridge_port_leave(struct net_device *dev,
struct net_device *br)
{
struct dsa_slave_priv *p = netdev_priv(dev);
- struct dsa_switch *ds = p->dp->ds;
+ struct dsa_notifier_bridge_info info = {
+ .sw_index = p->dp->ds->index,
+ .port = p->dp->index,
+ .br = br,
+ };
+ int err;

/* Here the port is already unbridged. Reflect the current configuration
* so that drivers can program their chips accordingly.
*/
p->dp->bridge_dev = NULL;

- if (ds->ops->port_bridge_leave)
- ds->ops->port_bridge_leave(ds, p->dp->index, br);
+ err = dsa_slave_notify(dev, DSA_NOTIFIER_BRIDGE_LEAVE, &info);
+ if (err)
+ netdev_err(dev, "failed to notify DSA_NOTIFIER_BRIDGE_LEAVE\n");

/* Port left the bridge, put in BR_STATE_DISABLED by the bridge layer,
* so allow it to be in BR_STATE_FORWARDING to be kept functional
diff --git a/net/dsa/switch.c b/net/dsa/switch.c
index e22fa7633d03..6456dacf9ae9 100644
--- a/net/dsa/switch.c
+++ b/net/dsa/switch.c
@@ -13,6 +13,32 @@
#include <linux/notifier.h>
#include <net/dsa.h>

+static int dsa_switch_bridge_join(struct dsa_switch *ds,
+ struct dsa_notifier_bridge_info *info)
+{
+ if (ds->index == info->sw_index && ds->ops->port_bridge_join)
+ return ds->ops->port_bridge_join(ds, info->port, info->br);
+
+ if (ds->index != info->sw_index)
+ dev_dbg(ds->dev, "crosschip DSA port %d.%d bridged to %s\n",
+ info->sw_index, info->port, netdev_name(info->br));
+
+ return 0;
+}
+
+static int dsa_switch_bridge_leave(struct dsa_switch *ds,
+ struct dsa_notifier_bridge_info *info)
+{
+ if (ds->index == info->sw_index && ds->ops->port_bridge_leave)
+ ds->ops->port_bridge_leave(ds, info->port, info->br);
+
+ if (ds->index != info->sw_index)
+ dev_dbg(ds->dev, "crosschip DSA port %d.%d unbridged from %s\n",
+ info->sw_index, info->port, netdev_name(info->br));
+
+ return 0;
+}
+
static int dsa_switch_event(struct notifier_block *nb,
unsigned long event, void *info)
{
@@ -20,6 +46,12 @@ static int dsa_switch_event(struct notifier_block *nb,
int err;

switch (event) {
+ case DSA_NOTIFIER_BRIDGE_JOIN:
+ err = dsa_switch_bridge_join(ds, info);
+ break;
+ case DSA_NOTIFIER_BRIDGE_LEAVE:
+ err = dsa_switch_bridge_leave(ds, info);
+ break;
default:
err = -EOPNOTSUPP;
break;
--
2.11.0