vxlan: Have vxlan_fdb_replace() save original rdst value

To enable rollbacks after vetoed FDB updates, extend vxlan_fdb_replace()
to take an additional argument where it should store the original values
of a modified rdst. Update the sole caller.

The following patch will make use of the saved value.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index aeaa429..1c8d8c8 100644 (file)
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -625,7 +625,7 @@ EXPORT_SYMBOL_GPL(vxlan_fdb_clear_offload);
 /* Replace destination of unicast mac */
 static int vxlan_fdb_replace(struct vxlan_fdb *f,
                             union vxlan_addr *ip, __be16 port, __be32 vni,
-                            __u32 ifindex)
+                            __u32 ifindex, struct vxlan_rdst *oldrd)
 {
        struct vxlan_rdst *rd;
 
@@ -637,6 +637,7 @@ static int vxlan_fdb_replace(struct vxlan_fdb *f,
        if (!rd)
                return 0;
 
+       *oldrd = *rd;
        dst_cache_reset(&rd->dst_cache);
        rd->remote_ip = *ip;
        rd->remote_port = port;
@@ -865,6 +866,7 @@ static int vxlan_fdb_update_existing(struct vxlan_dev *vxlan,
 {
        __u16 fdb_flags = (ndm_flags & ~NTF_USE);
        struct vxlan_rdst *rd = NULL;
+       struct vxlan_rdst oldrd;
        int notify = 0;
        int rc;
 
@@ -890,7 +892,7 @@ static int vxlan_fdb_update_existing(struct vxlan_dev *vxlan,
                if (!(is_multicast_ether_addr(f->eth_addr) ||
                      is_zero_ether_addr(f->eth_addr))) {
                        rc = vxlan_fdb_replace(f, ip, port, vni,
-                                              ifindex);
+                                              ifindex, &oldrd);
                        notify |= rc;
                } else {
                        return -EOPNOTSUPP;