[ovs-dev] [PATCH] netdev-vport: Use the vxlan dst_port in netdev name

[Chris Mi]

If vxlan dst_port is not default 4789, "ovs-dpctl dump-flows"
will fail. The error message is:

netdev_linux|INFO|ioctl(SIOCGIFINDEX) on vxlan_sys_4789 device failed: No such device

That's because when calling netdev_vport_construct() for netdev
vxlan_sys_xxxx, the default dst_port is used. Actually, the dst_port
value is in the name of the netdev. Use it to avoid the error.

Signed-off-by: Chris Mi <chrism at mellanox.com>
---

v1
==

Any comment about this patch? We are not sure if it is correct
to verify the port from the name. If it is correct, is it applicable
for other tunnels? Thanks!


 lib/netdev-vport.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/netdev-vport.c b/lib/netdev-vport.c
index 808a43f99..be68fad1a 100644
--- a/lib/netdev-vport.c
+++ b/lib/netdev-vport.c
@@ -189,17 +189,28 @@ netdev_vport_alloc(void)
 int
 netdev_vport_construct(struct netdev *netdev_)
 {
+    const struct netdev_class *class = netdev_get_class(netdev_);
+    const char *dpif_port = netdev_vport_class_get_dpif_port(class);
     struct netdev_vport *dev = netdev_vport_cast(netdev_);
     const char *type = netdev_get_type(netdev_);
 
     ovs_mutex_init(&dev->mutex);
     eth_addr_random(&dev->etheraddr);
 
-    /* Add a default destination port for tunnel ports if none specified. */
+    /* Add a default destination port for tunnel ports if none specified.
+     * For vxlan, the dst_port is in the netdev name when creating it, so
+     * use it instead of the default one */
     if (!strcmp(type, "geneve")) {
         dev->tnl_cfg.dst_port = htons(GENEVE_DST_PORT);
     } else if (!strcmp(type, "vxlan")) {
-        dev->tnl_cfg.dst_port = htons(VXLAN_DST_PORT);
+        const char *p, *name = netdev_->name;
+        uint16_t port = VXLAN_DST_PORT;
+
+        if (!strncmp(name, dpif_port, strlen(dpif_port))) {
+            p = name + strlen(dpif_port) + 1;
+            port = atoi(p);
+        }
+        dev->tnl_cfg.dst_port = htons(port);
         update_vxlan_global_cfg(netdev_, NULL, &dev->tnl_cfg);
     } else if (!strcmp(type, "lisp")) {
         dev->tnl_cfg.dst_port = htons(LISP_DST_PORT);
-- 
2.14.4