bridge: cfm: Netlink Notifications.

This is the implementation of Netlink notifications out of CFM.

Notifications are initiated whenever a state change happens in CFM.

IFLA_BRIDGE_CFM:
    Points to the CFM information.

IFLA_BRIDGE_CFM_MEP_STATUS_INFO:
    This indicate that the MEP instance status are following.
IFLA_BRIDGE_CFM_CC_PEER_STATUS_INFO:
    This indicate that the peer MEP status are following.

CFM nested attribute has the following attributes in next level.

IFLA_BRIDGE_CFM_MEP_STATUS_INSTANCE:
    The MEP instance number of the delivered status.
    The type is NLA_U32.
IFLA_BRIDGE_CFM_MEP_STATUS_OPCODE_UNEXP_SEEN:
    The MEP instance received CFM PDU with unexpected Opcode.
    The type is NLA_U32 (bool).
IFLA_BRIDGE_CFM_MEP_STATUS_VERSION_UNEXP_SEEN:
    The MEP instance received CFM PDU with unexpected version.
    The type is NLA_U32 (bool).
IFLA_BRIDGE_CFM_MEP_STATUS_RX_LEVEL_LOW_SEEN:
    The MEP instance received CCM PDU with MD level lower than
    configured level. This frame is discarded.
    The type is NLA_U32 (bool).

IFLA_BRIDGE_CFM_CC_PEER_STATUS_INSTANCE:
    The MEP instance number of the delivered status.
    The type is NLA_U32.
IFLA_BRIDGE_CFM_CC_PEER_STATUS_PEER_MEPID:
    The added Peer MEP ID of the delivered status.
    The type is NLA_U32.
IFLA_BRIDGE_CFM_CC_PEER_STATUS_CCM_DEFECT:
    The CCM defect status.
    The type is NLA_U32 (bool).
    True means no CCM frame is received for 3.25 intervals.
    IFLA_BRIDGE_CFM_CC_CONFIG_EXP_INTERVAL.
IFLA_BRIDGE_CFM_CC_PEER_STATUS_RDI:
    The last received CCM PDU RDI.
    The type is NLA_U32 (bool).
IFLA_BRIDGE_CFM_CC_PEER_STATUS_PORT_TLV_VALUE:
    The last received CCM PDU Port Status TLV value field.
    The type is NLA_U8.
IFLA_BRIDGE_CFM_CC_PEER_STATUS_IF_TLV_VALUE:
    The last received CCM PDU Interface Status TLV value field.
    The type is NLA_U8.
IFLA_BRIDGE_CFM_CC_PEER_STATUS_SEEN:
    A CCM frame has been received from Peer MEP.
    The type is NLA_U32 (bool).
    This is cleared after GETLINK IFLA_BRIDGE_CFM_CC_PEER_STATUS_INFO.
IFLA_BRIDGE_CFM_CC_PEER_STATUS_TLV_SEEN:
    A CCM frame with TLV has been received from Peer MEP.
    The type is NLA_U32 (bool).
    This is cleared after GETLINK IFLA_BRIDGE_CFM_CC_PEER_STATUS_INFO.
IFLA_BRIDGE_CFM_CC_PEER_STATUS_SEQ_UNEXP_SEEN:
    A CCM frame with unexpected sequence number has been received
    from Peer MEP.
    The type is NLA_U32 (bool).
    When a sequence number is not one higher than previously received
    then it is unexpected.
    This is cleared after GETLINK IFLA_BRIDGE_CFM_CC_PEER_STATUS_INFO.

Signed-off-by: Henrik Bjoernlund  <henrik.bjoernlund@microchip.com>
Reviewed-by: Horatiu Vultur  <horatiu.vultur@microchip.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 48 insertions, 0 deletions

diff --git a/net/bridge/br_cfm.c b/net/bridge/br_cfm.c
index 3912fedfd289..001064f7583d 100644
--- a/net/bridge/br_cfm.c
+++ b/net/bridge/br_cfm.c
@@ -138,6 +138,13 @@ static void ccm_rx_timer_start(struct br_cfm_peer_mep *peer_mep)
 			   usecs_to_jiffies(interval_us / 4));
 }
 
+static void br_cfm_notify(int event, const struct net_bridge_port *port)
+{
+	u32 filter = RTEXT_FILTER_CFM_STATUS;
+
+	return br_info_notify(event, port->br, NULL, filter);
+}
+
 static void cc_peer_enable(struct br_cfm_peer_mep *peer_mep)
 {
 	memset(&peer_mep->cc_status, 0, sizeof(peer_mep->cc_status));
@@ -288,6 +295,7 @@ static void ccm_tx_work_expired(struct work_struct *work)
 static void ccm_rx_work_expired(struct work_struct *work)
 {
 	struct br_cfm_peer_mep *peer_mep;
+	struct net_bridge_port *b_port;
 	struct delayed_work *del_work;
 
 	del_work = to_delayed_work(work);
@@ -305,6 +313,13 @@ static void ccm_rx_work_expired(struct work_struct *work)
 		 * CCM defect detected
 		 */
 		peer_mep->cc_status.ccm_defect = true;
+
+		/* Change in CCM defect status - notify */
+		rcu_read_lock();
+		b_port = rcu_dereference(peer_mep->mep->b_port);
+		if (b_port)
+			br_cfm_notify(RTM_NEWLINK, b_port);
+		rcu_read_unlock();
 	}
 }
 
@@ -430,6 +445,9 @@ static int br_cfm_frame_rx(struct net_bridge_port *port, struct sk_buff *skb)
 		if (peer_mep->cc_status.ccm_defect) {
 			peer_mep->cc_status.ccm_defect = false;
 
+			/* Change in CCM defect status - notify */
+			br_cfm_notify(RTM_NEWLINK, port);
+
 			/* Start CCM RX timer */
 			ccm_rx_timer_start(peer_mep);
 		}
@@ -799,6 +817,36 @@ save:
 	return 0;
 }
 
+int br_cfm_mep_count(struct net_bridge *br, u32 *count)
+{
+	struct br_cfm_mep *mep;
+
+	*count = 0;
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(mep, &br->mep_list, head)
+		*count += 1;
+	rcu_read_unlock();
+
+	return 0;
+}
+
+int br_cfm_peer_mep_count(struct net_bridge *br, u32 *count)
+{
+	struct br_cfm_peer_mep *peer_mep;
+	struct br_cfm_mep *mep;
+
+	*count = 0;
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(mep, &br->mep_list, head)
+		hlist_for_each_entry_rcu(peer_mep, &mep->peer_mep_list, head)
+			*count += 1;
+	rcu_read_unlock();
+
+	return 0;
+}
+
 bool br_cfm_created(struct net_bridge *br)
 {
 	return !hlist_empty(&br->mep_list);