diff options
Diffstat (limited to 'net/bridge/br_mrp.c')
| -rw-r--r-- | net/bridge/br_mrp.c | 677 |
1 files changed, 677 insertions, 0 deletions
diff --git a/net/bridge/br_mrp.c b/net/bridge/br_mrp.c new file mode 100644 index 000000000000..24986ec7d38c --- /dev/null +++ b/net/bridge/br_mrp.c @@ -0,0 +1,677 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <linux/mrp_bridge.h> +#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; + u16 *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; + + if (role == BR_MRP_PORT_ROLE_PRIMARY) + rcu_assign_pointer(mrp->p_port, p); + else + rcu_assign_pointer(mrp->s_port, p); + + 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); +} |