[PATCH net-next v5 10/10] bridge: cfm: Netlink Notifications.

Henrik Bjoernlund
2020-10-12T14:07:35Z

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>
---
net/bridge/br_cfm.c | 48 ++++++++++++++++++++++++
net/bridge/br_cfm_netlink.c | 25 ++++++++-----
net/bridge/br_netlink.c | 73 ++++++++++++++++++++++++++++++++-----
net/bridge/br_private.h | 22 ++++++++++-
4 files changed, 147 insertions(+), 21 deletions(-)

diff --git a/net/bridge/br_cfm.c b/net/bridge/br_cfm.c
index c8de462c2fd4..b945033934bc 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));
@@ -287,6 +294,7 @@ 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);
@@ -304,6 +312,13 @@ 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();
}
}

@@ -429,6 +444,9 @@ 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);
}
@@ -816,6 +834,36 @@ int br_cfm_cc_ccm_tx(struct net_bridge *br, const u32 instance,
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);
diff --git a/net/bridge/br_cfm_netlink.c b/net/bridge/br_cfm_netlink.c
index 506e352cc763..57882dbbf41f 100644
--- a/net/bridge/br_cfm_netlink.c
+++ b/net/bridge/br_cfm_netlink.c
@@ -613,7 +613,9 @@ int br_cfm_config_fill_info(struct sk_buff *skb, struct net_bridge *br)
return -EMSGSIZE;
}

-int br_cfm_status_fill_info(struct sk_buff *skb, struct net_bridge *br)
+int br_cfm_status_fill_info(struct sk_buff *skb,
+ struct net_bridge *br,
+ bool getlink)
{
struct br_cfm_peer_mep *peer_mep;
struct br_cfm_mep *mep;
@@ -643,10 +645,13 @@ int br_cfm_status_fill_info(struct sk_buff *skb, struct net_bridge *br)
mep->status.rx_level_low_seen))
goto nla_put_failure;

- /* Clear all 'seen' indications */
- mep->status.opcode_unexp_seen = false;
- mep->status.version_unexp_seen = false;
- mep->status.rx_level_low_seen = false;
+ /* Only clear if this is a GETLINK */
+ if (getlink) {
+ /* Clear all 'seen' indications */
+ mep->status.opcode_unexp_seen = false;
+ mep->status.version_unexp_seen = false;
+ mep->status.rx_level_low_seen = false;
+ }

nla_nest_end(skb, tb);

@@ -700,10 +705,12 @@ int br_cfm_status_fill_info(struct sk_buff *skb, struct net_bridge *br)
peer_mep->cc_status.seq_unexp_seen))
goto nla_put_failure;

- /* Clear all 'seen' indications */
- peer_mep->cc_status.seen = false;
- peer_mep->cc_status.tlv_seen = false;
- peer_mep->cc_status.seq_unexp_seen = false;
+ if (getlink) { /* Only clear if this is a GETLINK */
+ /* Clear all 'seen' indications */
+ peer_mep->cc_status.seen = false;
+ peer_mep->cc_status.tlv_seen = false;
+ peer_mep->cc_status.seq_unexp_seen = false;
+ }

nla_nest_end(skb, tb);
}
diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index 68c2ed87e26b..6952d4852942 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -94,9 +94,11 @@ static size_t br_get_link_af_size_filtered(const struct net_device *dev,
{
struct net_bridge_vlan_group *vg = NULL;
struct net_bridge_port *p = NULL;
- struct net_bridge *br;
- int num_vlan_infos;
+ struct net_bridge *br = NULL;
+ u32 num_cfm_peer_mep_infos;
+ u32 num_cfm_mep_infos;
size_t vinfo_sz = 0;
+ int num_vlan_infos;

rcu_read_lock();
if (netif_is_bridge_port(dev)) {
@@ -115,6 +117,49 @@ static size_t br_get_link_af_size_filtered(const struct net_device *dev,
/* Each VLAN is returned in bridge_vlan_info along with flags */
vinfo_sz += num_vlan_infos * nla_total_size(sizeof(struct bridge_vlan_info));

+ if (!(filter_mask & RTEXT_FILTER_CFM_STATUS))
+ return vinfo_sz;
+
+ if (!br)
+ return vinfo_sz;
+
+ /* CFM status info must be added */
+ br_cfm_mep_count(br, &num_cfm_mep_infos);
+ br_cfm_peer_mep_count(br, &num_cfm_peer_mep_infos);
+
+ vinfo_sz += nla_total_size(0); /* IFLA_BRIDGE_CFM */
+ /* For each status struct the MEP instance (u32) is added */
+ /* MEP instance (u32) + br_cfm_mep_status */
+ vinfo_sz += num_cfm_mep_infos *
+ /*IFLA_BRIDGE_CFM_MEP_STATUS_INSTANCE */
+ (nla_total_size(sizeof(u32))
+ /* IFLA_BRIDGE_CFM_MEP_STATUS_OPCODE_UNEXP_SEEN */
+ + nla_total_size(sizeof(u32))
+ /* IFLA_BRIDGE_CFM_MEP_STATUS_VERSION_UNEXP_SEEN */
+ + nla_total_size(sizeof(u32))
+ /* IFLA_BRIDGE_CFM_MEP_STATUS_RX_LEVEL_LOW_SEEN */
+ + nla_total_size(sizeof(u32)));
+ /* MEP instance (u32) + br_cfm_cc_peer_status */
+ vinfo_sz += num_cfm_peer_mep_infos *
+ /* IFLA_BRIDGE_CFM_CC_PEER_STATUS_INSTANCE */
+ (nla_total_size(sizeof(u32))
+ /* IFLA_BRIDGE_CFM_CC_PEER_STATUS_PEER_MEPID */
+ + nla_total_size(sizeof(u32))
+ /* IFLA_BRIDGE_CFM_CC_PEER_STATUS_CCM_DEFECT */
+ + nla_total_size(sizeof(u32))
+ /* IFLA_BRIDGE_CFM_CC_PEER_STATUS_RDI */
+ + nla_total_size(sizeof(u32))
+ /* IFLA_BRIDGE_CFM_CC_PEER_STATUS_PORT_TLV_VALUE */
+ + nla_total_size(sizeof(u8))
+ /* IFLA_BRIDGE_CFM_CC_PEER_STATUS_IF_TLV_VALUE */
+ + nla_total_size(sizeof(u8))
+ /* IFLA_BRIDGE_CFM_CC_PEER_STATUS_SEEN */
+ + nla_total_size(sizeof(u32))
+ /* IFLA_BRIDGE_CFM_CC_PEER_STATUS_TLV_SEEN */
+ + nla_total_size(sizeof(u32))
+ /* IFLA_BRIDGE_CFM_CC_PEER_STATUS_SEQ_UNEXP_SEEN */
+ + nla_total_size(sizeof(u32)));
+
return vinfo_sz;
}

@@ -378,7 +423,8 @@ static int br_fill_ifvlaninfo(struct sk_buff *skb,
static int br_fill_ifinfo(struct sk_buff *skb,
const struct net_bridge_port *port,
u32 pid, u32 seq, int event, unsigned int flags,
- u32 filter_mask, const struct net_device *dev)
+ u32 filter_mask, const struct net_device *dev,
+ bool getlink)
{
u8 operstate = netif_running(dev) ? dev->operstate : IF_OPER_DOWN;
struct nlattr *af = NULL;
@@ -499,7 +545,7 @@ static int br_fill_ifinfo(struct sk_buff *skb,

if (filter_mask & RTEXT_FILTER_CFM_STATUS) {
rcu_read_lock();
- err = br_cfm_status_fill_info(skb, br);
+ err = br_cfm_status_fill_info(skb, br, getlink);
rcu_read_unlock();
if (err)
goto nla_put_failure;
@@ -519,11 +565,9 @@ static int br_fill_ifinfo(struct sk_buff *skb,
return -EMSGSIZE;
}

-/* Notify listeners of a change in bridge or port information */
-void br_ifinfo_notify(int event, const struct net_bridge *br,
- const struct net_bridge_port *port)
+void br_info_notify(int event, const struct net_bridge *br,
+ const struct net_bridge_port *port, u32 filter)
{
- u32 filter = RTEXT_FILTER_BRVLAN_COMPRESSED;
struct net_device *dev;
struct sk_buff *skb;
int err = -ENOBUFS;
@@ -548,7 +592,7 @@ void br_ifinfo_notify(int event, const struct net_bridge *br,
if (skb == NULL)
goto errout;

- err = br_fill_ifinfo(skb, port, 0, 0, event, 0, filter, dev);
+ err = br_fill_ifinfo(skb, port, 0, 0, event, 0, filter, dev, false);
if (err < 0) {
/* -EMSGSIZE implies BUG in br_nlmsg_size() */
WARN_ON(err == -EMSGSIZE);
@@ -561,6 +605,15 @@ void br_ifinfo_notify(int event, const struct net_bridge *br,
rtnl_set_sk_err(net, RTNLGRP_LINK, err);
}

+/* Notify listeners of a change in bridge or port information */
+void br_ifinfo_notify(int event, const struct net_bridge *br,
+ const struct net_bridge_port *port)
+{
+ u32 filter = RTEXT_FILTER_BRVLAN_COMPRESSED;
+
+ return br_info_notify(event, br, port, filter);
+}
+
/*
* Dump information about all ports, in response to GETLINK
*/
@@ -577,7 +630,7 @@ int br_getlink(struct sk_buff *skb, u32 pid, u32 seq,
return 0;

return br_fill_ifinfo(skb, port, pid, seq, RTM_NEWLINK, nlflags,
- filter_mask, dev);
+ filter_mask, dev, true);
}

static int br_vlan_info(struct net_bridge *br, struct net_bridge_port *p,
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 228635b350a2..905d406a2fc7 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -1466,7 +1466,11 @@ int br_cfm_parse(struct net_bridge *br, struct net_bridge_port *p,
bool br_cfm_created(struct net_bridge *br);
void br_cfm_port_del(struct net_bridge *br, struct net_bridge_port *p);
int br_cfm_config_fill_info(struct sk_buff *skb, struct net_bridge *br);
-int br_cfm_status_fill_info(struct sk_buff *skb, struct net_bridge *br);
+int br_cfm_status_fill_info(struct sk_buff *skb,
+ struct net_bridge *br,
+ bool getlink);
+int br_cfm_mep_count(struct net_bridge *br, u32 *count);
+int br_cfm_peer_mep_count(struct net_bridge *br, u32 *count);
#else
static inline int br_cfm_parse(struct net_bridge *br, struct net_bridge_port *p,
struct nlattr *attr, int cmd,
@@ -1490,7 +1494,19 @@ static inline int br_cfm_config_fill_info(struct sk_buff *skb, struct net_bridge
return -EOPNOTSUPP;
}

-static inline int br_cfm_status_fill_info(struct sk_buff *skb, struct net_bridge *br)
+static inline int br_cfm_status_fill_info(struct sk_buff *skb,
+ struct net_bridge *br,
+ bool getlink)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline int br_cfm_mep_count(struct net_bridge *br, u32 *count)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline int br_cfm_peer_mep_count(struct net_bridge *br, u32 *count)
{
return -EOPNOTSUPP;
}
@@ -1502,6 +1518,8 @@ int br_netlink_init(void);
void br_netlink_fini(void);
void br_ifinfo_notify(int event, const struct net_bridge *br,
const struct net_bridge_port *port);
+void br_info_notify(int event, const struct net_bridge *br,
+ const struct net_bridge_port *port, u32 filter);
int br_setlink(struct net_device *dev, struct nlmsghdr *nlmsg, u16 flags,
struct netlink_ext_ack *extack);
int br_dellink(struct net_device *dev, struct nlmsghdr *nlmsg, u16 flags);
--
2.28.0