// SPDX-License-Identifier: GPL-2.0-or-later #include #include "br_private_mrp.h" static const u8 mrp_test_dmac[ETH_ALEN] = { 0x1, 0x15, 0x4e, 0x0, 0x0, 0x1 }; static struct net_bridge_port *br_mrp_get_port(struct net_bridge *br, u32 ifindex) { struct net_bridge_port *res = NULL; struct net_bridge_port *port; list_for_each_entry(port, &br->port_list, list) { if (port->dev->ifindex == ifindex) { res = port; break; } } return res; } static struct br_mrp *br_mrp_find_id(struct net_bridge *br, u32 ring_id) { struct br_mrp *res = NULL; struct br_mrp *mrp; list_for_each_entry_rcu(mrp, &br->mrp_list, list, lockdep_rtnl_is_held()) { if (mrp->ring_id == ring_id) { res = mrp; break; } } return res; } static bool br_mrp_unique_ifindex(struct net_bridge *br, u32 ifindex) { struct br_mrp *mrp; list_for_each_entry_rcu(mrp, &br->mrp_list, list, lockdep_rtnl_is_held()) { struct net_bridge_port *p; p = rtnl_dereference(mrp->p_port); if (p && p->dev->ifindex == ifindex) return false; p = rtnl_dereference(mrp->s_port); if (p && p->dev->ifindex == ifindex) return false; } return true; } static struct br_mrp *br_mrp_find_port(struct net_bridge *br, struct net_bridge_port *p) { struct br_mrp *res = NULL; struct br_mrp *mrp; list_for_each_entry_rcu(mrp, &br->mrp_list, list, lockdep_rtnl_is_held()) { if (rcu_access_pointer(mrp->p_port) == p || rcu_access_pointer(mrp->s_port) == p) { res = mrp; break; } } return res; } static int br_mrp_next_seq(struct br_mrp *mrp) { mrp->seq_id++; return mrp->seq_id; } static struct sk_buff *br_mrp_skb_alloc(struct net_bridge_port *p, const u8 *src, const u8 *dst) { struct ethhdr *eth_hdr; struct sk_buff *skb; __be16 *version; skb = dev_alloc_skb(MRP_MAX_FRAME_LENGTH); if (!skb) return NULL; skb->dev = p->dev; skb->protocol = htons(ETH_P_MRP); skb->priority = MRP_FRAME_PRIO; skb_reserve(skb, sizeof(*eth_hdr)); eth_hdr = skb_push(skb, sizeof(*eth_hdr)); ether_addr_copy(eth_hdr->h_dest, dst); ether_addr_copy(eth_hdr->h_source, src); eth_hdr->h_proto = htons(ETH_P_MRP); version = skb_put(skb, sizeof(*version)); *version = cpu_to_be16(MRP_VERSION); return skb; } static void br_mrp_skb_tlv(struct sk_buff *skb, enum br_mrp_tlv_header_type type, u8 length) { struct br_mrp_tlv_hdr *hdr; hdr = skb_put(skb, sizeof(*hdr)); hdr->type = type; hdr->length = length; } static void br_mrp_skb_common(struct sk_buff *skb, struct br_mrp *mrp) { struct br_mrp_common_hdr *hdr; br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_COMMON, sizeof(*hdr)); hdr = skb_put(skb, sizeof(*hdr)); hdr->seq_id = cpu_to_be16(br_mrp_next_seq(mrp)); memset(hdr->domain, 0xff, MRP_DOMAIN_UUID_LENGTH); } static struct sk_buff *br_mrp_alloc_test_skb(struct br_mrp *mrp, struct net_bridge_port *p, enum br_mrp_port_role_type port_role) { struct br_mrp_ring_test_hdr *hdr = NULL; struct sk_buff *skb = NULL; if (!p) return NULL; skb = br_mrp_skb_alloc(p, p->dev->dev_addr, mrp_test_dmac); if (!skb) return NULL; br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_RING_TEST, sizeof(*hdr)); hdr = skb_put(skb, sizeof(*hdr)); hdr->prio = cpu_to_be16(mrp->prio); ether_addr_copy(hdr->sa, p->br->dev->dev_addr); hdr->port_role = cpu_to_be16(port_role); hdr->state = cpu_to_be16(mrp->ring_state); hdr->transitions = cpu_to_be16(mrp->ring_transitions); hdr->timestamp = cpu_to_be32(jiffies_to_msecs(jiffies)); br_mrp_skb_common(skb, mrp); br_mrp_skb_tlv(skb, BR_MRP_TLV_HEADER_END, 0x0); return skb; } /* This function is continuously called in the following cases: * - when node role is MRM, in this case test_monitor is always set to false * because it needs to notify the userspace that the ring is open and needs to * send MRP_Test frames * - when node role is MRA, there are 2 subcases: * - when MRA behaves as MRM, in this case is similar with MRM role * - when MRA behaves as MRC, in this case test_monitor is set to true, * because it needs to detect when it stops seeing MRP_Test frames * from MRM node but it doesn't need to send MRP_Test frames. */ static void br_mrp_test_work_expired(struct work_struct *work) { struct delayed_work *del_work = to_delayed_work(work); struct br_mrp *mrp = container_of(del_work, struct br_mrp, test_work); struct net_bridge_port *p; bool notify_open = false; struct sk_buff *skb; if (time_before_eq(mrp->test_end, jiffies)) return; if (mrp->test_count_miss < mrp->test_max_miss) { mrp->test_count_miss++; } else { /* Notify that the ring is open only if the ring state is * closed, otherwise it would continue to notify at every * interval. * Also notify that the ring is open when the node has the * role MRA and behaves as MRC. The reason is that the * userspace needs to know when the MRM stopped sending * MRP_Test frames so that the current node to try to take * the role of a MRM. */ if (mrp->ring_state == BR_MRP_RING_STATE_CLOSED || mrp->test_monitor) notify_open = true; } rcu_read_lock(); p = rcu_dereference(mrp->p_port); if (p) { if (!mrp->test_monitor) { skb = br_mrp_alloc_test_skb(mrp, p, BR_MRP_PORT_ROLE_PRIMARY); if (!skb) goto out; skb_reset_network_header(skb); dev_queue_xmit(skb); } if (notify_open && !mrp->ring_role_offloaded) br_mrp_port_open(p->dev, true); } p = rcu_dereference(mrp->s_port); if (p) { if (!mrp->test_monitor) { skb = br_mrp_alloc_test_skb(mrp, p, BR_MRP_PORT_ROLE_SECONDARY); if (!skb) goto out; skb_reset_network_header(skb); dev_queue_xmit(skb); } if (notify_open && !mrp->ring_role_offloaded) br_mrp_port_open(p->dev, true); } out: rcu_read_unlock(); queue_delayed_work(system_wq, &mrp->test_work, usecs_to_jiffies(mrp->test_interval)); } /* Deletes the MRP instance. * note: called under rtnl_lock */ static void br_mrp_del_impl(struct net_bridge *br, struct br_mrp *mrp) { struct net_bridge_port *p; u8 state; /* Stop sending MRP_Test frames */ cancel_delayed_work_sync(&mrp->test_work); br_mrp_switchdev_send_ring_test(br, mrp, 0, 0, 0, 0); br_mrp_switchdev_del(br, mrp); /* Reset the ports */ p = rtnl_dereference(mrp->p_port); if (p) { spin_lock_bh(&br->lock); state = netif_running(br->dev) ? BR_STATE_FORWARDING : BR_STATE_DISABLED; p->state = state; p->flags &= ~BR_MRP_AWARE; spin_unlock_bh(&br->lock); br_mrp_port_switchdev_set_state(p, state); rcu_assign_pointer(mrp->p_port, NULL); } p = rtnl_dereference(mrp->s_port); if (p) { spin_lock_bh(&br->lock); state = netif_running(br->dev) ? BR_STATE_FORWARDING : BR_STATE_DISABLED; p->state = state; p->flags &= ~BR_MRP_AWARE; spin_unlock_bh(&br->lock); br_mrp_port_switchdev_set_state(p, state); rcu_assign_pointer(mrp->s_port, NULL); } list_del_rcu(&mrp->list); kfree_rcu(mrp, rcu); } /* Adds a new MRP instance. * note: called under rtnl_lock */ int br_mrp_add(struct net_bridge *br, struct br_mrp_instance *instance) { struct net_bridge_port *p; struct br_mrp *mrp; int err; /* If the ring exists, it is not possible to create another one with the * same ring_id */ mrp = br_mrp_find_id(br, instance->ring_id); if (mrp) return -EINVAL; if (!br_mrp_get_port(br, instance->p_ifindex) || !br_mrp_get_port(br, instance->s_ifindex)) return -EINVAL; /* It is not possible to have the same port part of multiple rings */ if (!br_mrp_unique_ifindex(br, instance->p_ifindex) || !br_mrp_unique_ifindex(br, instance->s_ifindex)) return -EINVAL; mrp = kzalloc(sizeof(*mrp), GFP_KERNEL); if (!mrp) return -ENOMEM; mrp->ring_id = instance->ring_id; mrp->prio = instance->prio; p = br_mrp_get_port(br, instance->p_ifindex); spin_lock_bh(&br->lock); p->state = BR_STATE_FORWARDING; p->flags |= BR_MRP_AWARE; spin_unlock_bh(&br->lock); rcu_assign_pointer(mrp->p_port, p); p = br_mrp_get_port(br, instance->s_ifindex); spin_lock_bh(&br->lock); p->state = BR_STATE_FORWARDING; p->flags |= BR_MRP_AWARE; spin_unlock_bh(&br->lock); rcu_assign_pointer(mrp->s_port, p); INIT_DELAYED_WORK(&mrp->test_work, br_mrp_test_work_expired); list_add_tail_rcu(&mrp->list, &br->mrp_list); err = br_mrp_switchdev_add(br, mrp); if (err) goto delete_mrp; return 0; delete_mrp: br_mrp_del_impl(br, mrp); return err; } /* Deletes the MRP instance from which the port is part of * note: called under rtnl_lock */ void br_mrp_port_del(struct net_bridge *br, struct net_bridge_port *p) { struct br_mrp *mrp = br_mrp_find_port(br, p); /* If the port is not part of a MRP instance just bail out */ if (!mrp) return; br_mrp_del_impl(br, mrp); } /* Deletes existing MRP instance based on ring_id * note: called under rtnl_lock */ int br_mrp_del(struct net_bridge *br, struct br_mrp_instance *instance) { struct br_mrp *mrp = br_mrp_find_id(br, instance->ring_id); if (!mrp) return -EINVAL; br_mrp_del_impl(br, mrp); return 0; } /* Set port state, port state can be forwarding, blocked or disabled * note: already called with rtnl_lock */ int br_mrp_set_port_state(struct net_bridge_port *p, enum br_mrp_port_state_type state) { if (!p || !(p->flags & BR_MRP_AWARE)) return -EINVAL; spin_lock_bh(&p->br->lock); if (state == BR_MRP_PORT_STATE_FORWARDING) p->state = BR_STATE_FORWARDING; else p->state = BR_STATE_BLOCKING; spin_unlock_bh(&p->br->lock); br_mrp_port_switchdev_set_state(p, state); return 0; } /* Set port role, port role can be primary or secondary * note: already called with rtnl_lock */ int br_mrp_set_port_role(struct net_bridge_port *p, enum br_mrp_port_role_type role) { struct br_mrp *mrp; if (!p || !(p->flags & BR_MRP_AWARE)) return -EINVAL; mrp = br_mrp_find_port(p->br, p); if (!mrp) return -EINVAL; switch (role) { case BR_MRP_PORT_ROLE_PRIMARY: rcu_assign_pointer(mrp->p_port, p); break; case BR_MRP_PORT_ROLE_SECONDARY: rcu_assign_pointer(mrp->s_port, p); break; default: return -EINVAL; } br_mrp_port_switchdev_set_role(p, role); return 0; } /* Set ring state, ring state can be only Open or Closed * note: already called with rtnl_lock */ int br_mrp_set_ring_state(struct net_bridge *br, struct br_mrp_ring_state *state) { struct br_mrp *mrp = br_mrp_find_id(br, state->ring_id); if (!mrp) return -EINVAL; if (mrp->ring_state == BR_MRP_RING_STATE_CLOSED && state->ring_state != BR_MRP_RING_STATE_CLOSED) mrp->ring_transitions++; mrp->ring_state = state->ring_state; br_mrp_switchdev_set_ring_state(br, mrp, state->ring_state); return 0; } /* Set ring role, ring role can be only MRM(Media Redundancy Manager) or * MRC(Media Redundancy Client). * note: already called with rtnl_lock */ int br_mrp_set_ring_role(struct net_bridge *br, struct br_mrp_ring_role *role) { struct br_mrp *mrp = br_mrp_find_id(br, role->ring_id); int err; if (!mrp) return -EINVAL; mrp->ring_role = role->ring_role; /* If there is an error just bailed out */ err = br_mrp_switchdev_set_ring_role(br, mrp, role->ring_role); if (err && err != -EOPNOTSUPP) return err; /* Now detect if the HW actually applied the role or not. If the HW * applied the role it means that the SW will not to do those operations * anymore. For example if the role ir MRM then the HW will notify the * SW when ring is open, but if the is not pushed to the HW the SW will * need to detect when the ring is open */ mrp->ring_role_offloaded = err == -EOPNOTSUPP ? 0 : 1; return 0; } /* Start to generate or monitor MRP test frames, the frames are generated by * HW and if it fails, they are generated by the SW. * note: already called with rtnl_lock */ int br_mrp_start_test(struct net_bridge *br, struct br_mrp_start_test *test) { struct br_mrp *mrp = br_mrp_find_id(br, test->ring_id); if (!mrp) return -EINVAL; /* Try to push it to the HW and if it fails then continue with SW * implementation and if that also fails then return error. */ if (!br_mrp_switchdev_send_ring_test(br, mrp, test->interval, test->max_miss, test->period, test->monitor)) return 0; mrp->test_interval = test->interval; mrp->test_end = jiffies + usecs_to_jiffies(test->period); mrp->test_max_miss = test->max_miss; mrp->test_monitor = test->monitor; mrp->test_count_miss = 0; queue_delayed_work(system_wq, &mrp->test_work, usecs_to_jiffies(test->interval)); return 0; } /* Process only MRP Test frame. All the other MRP frames are processed by * userspace application * note: already called with rcu_read_lock */ static void br_mrp_mrm_process(struct br_mrp *mrp, struct net_bridge_port *port, struct sk_buff *skb) { const struct br_mrp_tlv_hdr *hdr; struct br_mrp_tlv_hdr _hdr; /* Each MRP header starts with a version field which is 16 bits. * Therefore skip the version and get directly the TLV header. */ hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr); if (!hdr) return; if (hdr->type != BR_MRP_TLV_HEADER_RING_TEST) return; mrp->test_count_miss = 0; /* Notify the userspace that the ring is closed only when the ring is * not closed */ if (mrp->ring_state != BR_MRP_RING_STATE_CLOSED) br_mrp_port_open(port->dev, false); } /* Determin if the test hdr has a better priority than the node */ static bool br_mrp_test_better_than_own(struct br_mrp *mrp, struct net_bridge *br, const struct br_mrp_ring_test_hdr *hdr) { u16 prio = be16_to_cpu(hdr->prio); if (prio < mrp->prio || (prio == mrp->prio && ether_addr_to_u64(hdr->sa) < ether_addr_to_u64(br->dev->dev_addr))) return true; return false; } /* Process only MRP Test frame. All the other MRP frames are processed by * userspace application * note: already called with rcu_read_lock */ static void br_mrp_mra_process(struct br_mrp *mrp, struct net_bridge *br, struct net_bridge_port *port, struct sk_buff *skb) { const struct br_mrp_ring_test_hdr *test_hdr; struct br_mrp_ring_test_hdr _test_hdr; const struct br_mrp_tlv_hdr *hdr; struct br_mrp_tlv_hdr _hdr; /* Each MRP header starts with a version field which is 16 bits. * Therefore skip the version and get directly the TLV header. */ hdr = skb_header_pointer(skb, sizeof(uint16_t), sizeof(_hdr), &_hdr); if (!hdr) return; if (hdr->type != BR_MRP_TLV_HEADER_RING_TEST) return; test_hdr = skb_header_pointer(skb, sizeof(uint16_t) + sizeof(_hdr), sizeof(_test_hdr), &_test_hdr); if (!test_hdr) return; /* Only frames that have a better priority than the node will * clear the miss counter because otherwise the node will need to behave * as MRM. */ if (br_mrp_test_better_than_own(mrp, br, test_hdr)) mrp->test_count_miss = 0; } /* This will just forward the frame to the other mrp ring port(MRC role) or will * not do anything. * note: already called with rcu_read_lock */ static int br_mrp_rcv(struct net_bridge_port *p, struct sk_buff *skb, struct net_device *dev) { struct net_device *s_dev, *p_dev, *d_dev; struct net_bridge_port *p_port, *s_port; struct net_bridge *br; struct sk_buff *nskb; struct br_mrp *mrp; /* If port is disabled don't accept any frames */ if (p->state == BR_STATE_DISABLED) return 0; br = p->br; mrp = br_mrp_find_port(br, p); if (unlikely(!mrp)) return 0; p_port = rcu_dereference(mrp->p_port); if (!p_port) return 0; s_port = rcu_dereference(mrp->s_port); if (!s_port) return 0; /* If the role is MRM then don't forward the frames */ if (mrp->ring_role == BR_MRP_RING_ROLE_MRM) { br_mrp_mrm_process(mrp, p, skb); return 1; } /* If the role is MRA then don't forward the frames if it behaves as * MRM node */ if (mrp->ring_role == BR_MRP_RING_ROLE_MRA) { if (!mrp->test_monitor) { br_mrp_mrm_process(mrp, p, skb); return 1; } br_mrp_mra_process(mrp, br, p, skb); } /* Clone the frame and forward it on the other MRP port */ nskb = skb_clone(skb, GFP_ATOMIC); if (!nskb) return 0; p_dev = p_port->dev; s_dev = s_port->dev; if (p_dev == dev) d_dev = s_dev; else d_dev = p_dev; nskb->dev = d_dev; skb_push(nskb, ETH_HLEN); dev_queue_xmit(nskb); return 1; } /* Check if the frame was received on a port that is part of MRP ring * and if the frame has MRP eth. In that case process the frame otherwise do * normal forwarding. * note: already called with rcu_read_lock */ int br_mrp_process(struct net_bridge_port *p, struct sk_buff *skb) { /* If there is no MRP instance do normal forwarding */ if (likely(!(p->flags & BR_MRP_AWARE))) goto out; if (unlikely(skb->protocol == htons(ETH_P_MRP))) return br_mrp_rcv(p, skb, p->dev); out: return 0; } bool br_mrp_enabled(struct net_bridge *br) { return !list_empty(&br->mrp_list); }