/* called under bridge lock */ static int br_should_become_designated_port(struct net_bridge_port *p) { struct net_bridge *br; int t; br = p->br; if (br_is_designated_port(p)) return 1; if (memcmp(&p->designated_root, &br->designated_root, 8)) return 1; if (br->root_path_cost < p->designated_cost) return 1; else if (br->root_path_cost > p->designated_cost) return 0; t = memcmp(&br->bridge_id, &p->designated_bridge, 8); if (t < 0) return 1; else if (t > 0) return 0; if (p->port_id < p->designated_port) return 1; return 0; }
/* lock-safe */ void br_received_tcn_bpdu(struct net_bridge_port *p) { read_lock(&p->br->lock); if (p->state != BR_STATE_DISABLED && br_is_designated_port(p)) { // printk(KERN_INFO "%s: received tcn bpdu on port %i(%s)\n", // p->br->dev.name, p->port_no, p->dev->name); br_topology_change_detection(p->br); br_topology_change_acknowledge(p); } read_unlock(&p->br->lock); }
/* called under bridge lock */ void br_config_bpdu_generation(struct net_bridge *br) { struct net_bridge_port *p; p = br->port_list; while (p != NULL) { if (p->state != BR_STATE_DISABLED && br_is_designated_port(p)) br_transmit_config(p); p = p->next; } }
/* called under bridge lock */ static int br_should_become_root_port(struct net_bridge_port *p, int root_port) { struct net_bridge *br; struct net_bridge_port *rp; int t; br = p->br; if (p->state == BR_STATE_DISABLED || br_is_designated_port(p)) return 0; if (memcmp(&br->bridge_id, &p->designated_root, 8) <= 0) return 0; if (!root_port) return 1; rp = br_get_port(br, root_port); t = memcmp(&p->designated_root, &rp->designated_root, 8); if (t < 0) return 1; else if (t > 0) return 0; if (p->designated_cost + p->path_cost < rp->designated_cost + rp->path_cost) return 1; else if (p->designated_cost + p->path_cost > rp->designated_cost + rp->path_cost) return 0; t = memcmp(&p->designated_bridge, &rp->designated_bridge, 8); if (t < 0) return 1; else if (t > 0) return 0; if (p->designated_port < rp->designated_port) return 1; else if (p->designated_port > rp->designated_port) return 0; if (p->port_id < rp->port_id) return 1; return 0; }
/* called under bridge lock */ void br_stp_set_bridge_priority(struct net_bridge *br, int newprio) { struct net_bridge_port *p; int wasroot; wasroot = br_is_root_bridge(br); p = br->port_list; while (p != NULL) { if (p->state != BR_STATE_DISABLED && br_is_designated_port(p)) { p->designated_bridge.prio[0] = (newprio >> 8) & 0xFF; p->designated_bridge.prio[1] = newprio & 0xFF; } p = p->next; }
/* lock-safe */ void br_received_config_bpdu(struct net_bridge_port *p, struct br_config_bpdu *bpdu) { struct net_bridge *br; int was_root; if (p->state == BR_STATE_DISABLED) return; br = p->br; read_lock(&br->lock); was_root = br_is_root_bridge(br); if (br_supersedes_port_info(p, bpdu)) { br_record_config_information(p, bpdu); br_configuration_update(br); br_port_state_selection(br); if (!br_is_root_bridge(br) && was_root) { br_timer_clear(&br->hello_timer); if (br->topology_change_detected) { br_timer_clear(&br->topology_change_timer); br_transmit_tcn(br); br_timer_set(&br->tcn_timer, jiffies); } } if (p->port_no == br->root_port) { br_record_config_timeout_values(br, bpdu); br_config_bpdu_generation(br); if (bpdu->topology_change_ack) br_topology_change_acknowledged(br); } } else if (br_is_designated_port(p)) { br_reply(p); } read_unlock(&br->lock); }
/* called under bridge lock */ void br_port_state_selection(struct net_bridge *br) { struct net_bridge_port *p; p = br->port_list; while (p != NULL) { if (p->state != BR_STATE_DISABLED) { if (p->port_no == br->root_port) { p->config_pending = 0; p->topology_change_ack = 0; br_make_forwarding(p); } else if (br_is_designated_port(p)) { br_timer_clear(&p->message_age_timer); br_make_forwarding(p); } else { p->config_pending = 0; p->topology_change_ack = 0; br_make_blocking(p); } } p = p->next; } }