@@ -570,6 +570,7 @@ enum {
IFLA_BRPORT_MCAST_N_GROUPS,
IFLA_BRPORT_MCAST_MAX_GROUPS,
IFLA_BRPORT_NEIGH_VLAN_SUPPRESS,
+ IFLA_BRPORT_BACKUP_NHID,
__IFLA_BRPORT_MAX
};
#define IFLA_BRPORT_MAX (__IFLA_BRPORT_MAX - 1)
@@ -154,6 +154,7 @@ void br_forward(const struct net_bridge_port *to,
backup_port = rcu_dereference(to->backup_port);
if (unlikely(!backup_port))
goto out;
+ BR_INPUT_SKB_CB(skb)->backup_nhid = READ_ONCE(to->backup_nhid);
to = backup_port;
}
@@ -211,6 +211,7 @@ static inline size_t br_port_info_size(void)
+ nla_total_size(sizeof(u8)) /* IFLA_BRPORT_MRP_IN_OPEN */
+ nla_total_size(sizeof(u32)) /* IFLA_BRPORT_MCAST_EHT_HOSTS_LIMIT */
+ nla_total_size(sizeof(u32)) /* IFLA_BRPORT_MCAST_EHT_HOSTS_CNT */
+ + nla_total_size(sizeof(u32)) /* IFLA_BRPORT_BACKUP_NHID */
+ 0;
}
@@ -319,6 +320,10 @@ static int br_port_fill_attrs(struct sk_buff *skb,
backup_p->dev->ifindex);
rcu_read_unlock();
+ if (p->backup_nhid &&
+ nla_put_u32(skb, IFLA_BRPORT_BACKUP_NHID, p->backup_nhid))
+ return -EMSGSIZE;
+
return 0;
}
@@ -895,6 +900,7 @@ static const struct nla_policy br_port_policy[IFLA_BRPORT_MAX + 1] = {
[IFLA_BRPORT_MCAST_N_GROUPS] = { .type = NLA_REJECT },
[IFLA_BRPORT_MCAST_MAX_GROUPS] = { .type = NLA_U32 },
[IFLA_BRPORT_NEIGH_VLAN_SUPPRESS] = NLA_POLICY_MAX(NLA_U8, 1),
+ [IFLA_BRPORT_BACKUP_NHID] = { .type = NLA_U32 },
};
/* Change the state of the port and notify spanning tree */
@@ -1065,6 +1071,12 @@ static int br_setport(struct net_bridge_port *p, struct nlattr *tb[],
return err;
}
+ if (tb[IFLA_BRPORT_BACKUP_NHID]) {
+ u32 backup_nhid = nla_get_u32(tb[IFLA_BRPORT_BACKUP_NHID]);
+
+ WRITE_ONCE(p->backup_nhid, backup_nhid);
+ }
+
return 0;
}
@@ -387,6 +387,7 @@ struct net_bridge_port {
struct net_bridge_vlan_group __rcu *vlgrp;
#endif
struct net_bridge_port __rcu *backup_port;
+ u32 backup_nhid;
/* STP */
u8 priority;
@@ -605,6 +606,8 @@ struct br_input_skb_cb {
*/
unsigned long fwd_hwdoms;
#endif
+
+ u32 backup_nhid;
};
#define BR_INPUT_SKB_CB(__skb) ((struct br_input_skb_cb *)(__skb)->cb)
@@ -201,6 +201,21 @@ int br_handle_egress_vlan_tunnel(struct sk_buff *skb,
if (err)
return err;
+ if (BR_INPUT_SKB_CB(skb)->backup_nhid) {
+ tunnel_dst = __ip_tun_set_dst(0, 0, 0, 0, 0, TUNNEL_KEY,
+ tunnel_id, 0);
+ if (!tunnel_dst)
+ return -ENOMEM;
+
+ tunnel_dst->u.tun_info.mode |= IP_TUNNEL_INFO_TX |
+ IP_TUNNEL_INFO_BRIDGE;
+ tunnel_dst->u.tun_info.key.nhid =
+ BR_INPUT_SKB_CB(skb)->backup_nhid;
+ skb_dst_set(skb, &tunnel_dst->dst);
+
+ return 0;
+ }
+
tunnel_dst = rcu_dereference(vlan->tinfo.tunnel_dst);
if (tunnel_dst && dst_hold_safe(&tunnel_dst->dst))
skb_dst_set(skb, &tunnel_dst->dst);
@@ -61,7 +61,7 @@
#include "dev.h"
#define RTNL_MAX_TYPE 50
-#define RTNL_SLAVE_MAX_TYPE 43
+#define RTNL_SLAVE_MAX_TYPE 44
struct rtnl_link {
rtnl_doit_func doit;
Add a new bridge port attribute that allows attaching a nexthop object ID to an skb that is redirected to a backup bridge port with VLAN tunneling enabled. Specifically, when redirecting a known unicast packet, read the backup nexthop ID from the bridge port that lost its carrier and set it in the bridge control block of the skb before forwarding it via the backup port. Note that reading the ID from the bridge port should not result in a cache miss as the ID is added next to the 'backup_port' field that was already accessed. After this change, the 'state' field still stays on the first cache line, together with other data path related fields such as 'flags and 'vlgrp': struct net_bridge_port { struct net_bridge * br; /* 0 8 */ struct net_device * dev; /* 8 8 */ netdevice_tracker dev_tracker; /* 16 0 */ struct list_head list; /* 16 16 */ long unsigned int flags; /* 32 8 */ struct net_bridge_vlan_group * vlgrp; /* 40 8 */ struct net_bridge_port * backup_port; /* 48 8 */ u32 backup_nhid; /* 56 4 */ u8 priority; /* 60 1 */ u8 state; /* 61 1 */ u16 port_no; /* 62 2 */ /* --- cacheline 1 boundary (64 bytes) --- */ [...] } __attribute__((__aligned__(8))); When forwarding an skb via a bridge port that has VLAN tunneling enabled, check if the backup nexthop ID stored in the bridge control block is valid (i.e., not zero). If so, instead of attaching the pre-allocated metadata (that only has the tunnel key set), allocate a new metadata, set both the tunnel key and the nexthop object ID and attach it to the skb. By default, do not dump the new attribute to user space as a value of zero is an invalid nexthop object ID. The above is useful for EVPN multihoming. When one of the links composing an Ethernet Segment (ES) fails, traffic needs to be redirected towards the host via one of the other ES peers. For example, if a host is multihomed to three different VTEPs, the backup port of each ES link needs to be set to the VXLAN device and the backup nexthop ID needs to point to an FDB nexthop group that includes the IP addresses of the other two VTEPs. The VXLAN driver will extract the ID from the metadata of the redirected skb, calculate its flow hash and forward it towards one of the other VTEPs. If the ID does not exist, or represents an invalid nexthop object, the VXLAN driver will drop the skb. This relieves the bridge driver from the need to validate the ID. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> --- include/uapi/linux/if_link.h | 1 + net/bridge/br_forward.c | 1 + net/bridge/br_netlink.c | 12 ++++++++++++ net/bridge/br_private.h | 3 +++ net/bridge/br_vlan_tunnel.c | 15 +++++++++++++++ net/core/rtnetlink.c | 2 +- 6 files changed, 33 insertions(+), 1 deletion(-)