+/* Check for and handle port changes in 'backer''s dpif. */
+static void
+process_dpif_port_changes(struct dpif_backer *backer)
+{
+ for (;;) {
+ char *devname;
+ int error;
+
+ error = dpif_port_poll(backer->dpif, &devname);
+ switch (error) {
+ case EAGAIN:
+ return;
+
+ case ENOBUFS:
+ process_dpif_all_ports_changed(backer);
+ break;
+
+ case 0:
+ process_dpif_port_change(backer, devname);
+ free(devname);
+ break;
+
+ default:
+ process_dpif_port_error(backer, error);
+ break;
+ }
+ }
+}
+
+static void
+process_dpif_all_ports_changed(struct dpif_backer *backer)
+{
+ struct ofproto_dpif *ofproto;
+ struct dpif_port dpif_port;
+ struct dpif_port_dump dump;
+ struct sset devnames;
+ const char *devname;
+
+ sset_init(&devnames);
+ HMAP_FOR_EACH (ofproto, all_ofproto_dpifs_node, &all_ofproto_dpifs) {
+ if (ofproto->backer == backer) {
+ struct ofport *ofport;
+
+ HMAP_FOR_EACH (ofport, hmap_node, &ofproto->up.ports) {
+ sset_add(&devnames, netdev_get_name(ofport->netdev));
+ }
+ }
+ }
+ DPIF_PORT_FOR_EACH (&dpif_port, &dump, backer->dpif) {
+ sset_add(&devnames, dpif_port.name);
+ }
+
+ SSET_FOR_EACH (devname, &devnames) {
+ process_dpif_port_change(backer, devname);
+ }
+ sset_destroy(&devnames);
+}
+
+static void
+process_dpif_port_change(struct dpif_backer *backer, const char *devname)
+{
+ struct ofproto_dpif *ofproto;
+ struct dpif_port port;
+
+ /* Don't report on the datapath's device. */
+ if (!strcmp(devname, dpif_base_name(backer->dpif))) {
+ return;
+ }
+
+ HMAP_FOR_EACH (ofproto, all_ofproto_dpifs_node,
+ &all_ofproto_dpifs) {
+ if (simap_contains(&ofproto->backer->tnl_backers, devname)) {
+ return;
+ }
+ }
+
+ ofproto = lookup_ofproto_dpif_by_port_name(devname);
+ if (dpif_port_query_by_name(backer->dpif, devname, &port)) {
+ /* The port was removed. If we know the datapath,
+ * report it through poll_set(). If we don't, it may be
+ * notifying us of a removal we initiated, so ignore it.
+ * If there's a pending ENOBUFS, let it stand, since
+ * everything will be reevaluated. */
+ if (ofproto && ofproto->port_poll_errno != ENOBUFS) {
+ sset_add(&ofproto->port_poll_set, devname);
+ ofproto->port_poll_errno = 0;
+ }
+ } else if (!ofproto) {
+ /* The port was added, but we don't know with which
+ * ofproto we should associate it. Delete it. */
+ dpif_port_del(backer->dpif, port.port_no);
+ }
+ dpif_port_destroy(&port);
+}
+
+/* Propagate 'error' to all ofprotos based on 'backer'. */
+static void
+process_dpif_port_error(struct dpif_backer *backer, int error)
+{
+ struct ofproto_dpif *ofproto;
+
+ HMAP_FOR_EACH (ofproto, all_ofproto_dpifs_node, &all_ofproto_dpifs) {
+ if (ofproto->backer == backer) {
+ sset_clear(&ofproto->port_poll_set);
+ ofproto->port_poll_errno = error;
+ }
+ }
+}
+