sfc: neighbour lookup for TC encap action offload
authorEdward Cree <ecree.xilinx@gmail.com>
Thu, 8 Jun 2023 16:42:34 +0000 (17:42 +0100)
committerJakub Kicinski <kuba@kernel.org>
Sat, 10 Jun 2023 07:11:49 +0000 (00:11 -0700)
For each neighbour we're interested in, create a struct efx_neigh_binder
 object which has a list of all the encap_actions using it.  When we
 receive a neighbouring update (through the netevent notifier), find the
 corresponding efx_neigh_binder and update all its users.
Since the actual generation of encap headers is still only a stub, the
 resulting rules still get left on fallback actions.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
drivers/net/ethernet/sfc/ef100_netdev.c
drivers/net/ethernet/sfc/net_driver.h
drivers/net/ethernet/sfc/tc.c
drivers/net/ethernet/sfc/tc.h
drivers/net/ethernet/sfc/tc_bindings.c
drivers/net/ethernet/sfc/tc_bindings.h
drivers/net/ethernet/sfc/tc_encap_actions.c
drivers/net/ethernet/sfc/tc_encap_actions.h

index 274f3a2..7f7d560 100644 (file)
@@ -24,6 +24,7 @@
 #include "rx_common.h"
 #include "ef100_sriov.h"
 #include "tc_bindings.h"
+#include "tc_encap_actions.h"
 #include "efx_devlink.h"
 
 static void ef100_update_name(struct efx_nic *efx)
@@ -300,14 +301,38 @@ int ef100_netdev_event(struct notifier_block *this,
 {
        struct efx_nic *efx = container_of(this, struct efx_nic, netdev_notifier);
        struct net_device *net_dev = netdev_notifier_info_to_dev(ptr);
+       struct ef100_nic_data *nic_data = efx->nic_data;
+       int err;
 
        if (efx->net_dev == net_dev &&
            (event == NETDEV_CHANGENAME || event == NETDEV_REGISTER))
                ef100_update_name(efx);
 
+       if (!nic_data->grp_mae)
+               return NOTIFY_DONE;
+       err = efx_tc_netdev_event(efx, event, net_dev);
+       if (err & NOTIFY_STOP_MASK)
+               return err;
+
        return NOTIFY_DONE;
 }
 
+static int ef100_netevent_event(struct notifier_block *this,
+                               unsigned long event, void *ptr)
+{
+       struct efx_nic *efx = container_of(this, struct efx_nic, netevent_notifier);
+       struct ef100_nic_data *nic_data = efx->nic_data;
+       int err;
+
+       if (!nic_data->grp_mae)
+               return NOTIFY_DONE;
+       err = efx_tc_netevent_event(efx, event, ptr);
+       if (err & NOTIFY_STOP_MASK)
+               return err;
+
+       return NOTIFY_DONE;
+};
+
 static int ef100_register_netdev(struct efx_nic *efx)
 {
        struct net_device *net_dev = efx->net_dev;
@@ -367,6 +392,7 @@ void ef100_remove_netdev(struct efx_probe_data *probe_data)
        rtnl_unlock();
 
        unregister_netdevice_notifier(&efx->netdev_notifier);
+       unregister_netevent_notifier(&efx->netevent_notifier);
 #if defined(CONFIG_SFC_SRIOV)
        if (!efx->type->is_vf)
                efx_ef100_pci_sriov_disable(efx, true);
@@ -487,6 +513,14 @@ int ef100_probe_netdev(struct efx_probe_data *probe_data)
                goto fail;
        }
 
+       efx->netevent_notifier.notifier_call = ef100_netevent_event;
+       rc = register_netevent_notifier(&efx->netevent_notifier);
+       if (rc) {
+               netif_err(efx, probe, efx->net_dev,
+                         "Failed to register netevent notifier, rc=%d\n", rc);
+               goto fail;
+       }
+
        efx_probe_devlink_unlock(efx);
        return rc;
 fail:
index fcd51d3..a7a22b0 100644 (file)
@@ -27,6 +27,7 @@
 #include <linux/mtd/mtd.h>
 #include <net/busy_poll.h>
 #include <net/xdp.h>
+#include <net/netevent.h>
 
 #include "enum.h"
 #include "bitfield.h"
@@ -996,6 +997,7 @@ struct efx_mae;
  * @xdp_rxq_info_failed: Have any of the rx queues failed to initialise their
  *      xdp_rxq_info structures?
  * @netdev_notifier: Netdevice notifier.
+ * @netevent_notifier: Netevent notifier (for neighbour updates).
  * @tc: state for TC offload (EF100).
  * @devlink: reference to devlink structure owned by this device
  * @dl_port: devlink port associated with the PF
@@ -1183,6 +1185,7 @@ struct efx_nic {
        bool xdp_rxq_info_failed;
 
        struct notifier_block netdev_notifier;
+       struct notifier_block netevent_notifier;
        struct efx_tc_state *tc;
 
        struct devlink *devlink;
index 4177fec..77acdb6 100644 (file)
@@ -34,8 +34,8 @@ enum efx_encap_type efx_tc_indr_netdev_type(struct net_device *net_dev)
  * May return NULL for the PF (us), or an error pointer for a device that
  * isn't supported as a TC offload endpoint
  */
-static struct efx_rep *efx_tc_flower_lookup_efv(struct efx_nic *efx,
-                                               struct net_device *dev)
+struct efx_rep *efx_tc_flower_lookup_efv(struct efx_nic *efx,
+                                        struct net_device *dev)
 {
        struct efx_rep *efv;
 
@@ -71,7 +71,7 @@ static s64 efx_tc_flower_internal_mport(struct efx_nic *efx, struct efx_rep *efv
 }
 
 /* Convert a driver-internal vport ID into an external device (wire or VF) */
-static s64 efx_tc_flower_external_mport(struct efx_nic *efx, struct efx_rep *efv)
+s64 efx_tc_flower_external_mport(struct efx_nic *efx, struct efx_rep *efv)
 {
        u32 mport;
 
@@ -112,8 +112,10 @@ static void efx_tc_free_action_set(struct efx_nic *efx,
        }
        if (act->count)
                efx_tc_flower_put_counter_index(efx, act->count);
-       if (act->encap_md)
+       if (act->encap_md) {
+               list_del(&act->encap_user);
                efx_tc_flower_release_encap_md(efx, act->encap_md);
+       }
        kfree(act);
 }
 
@@ -1115,6 +1117,7 @@ static int efx_tc_flower_replace(struct efx_nic *efx,
                                        goto release;
                                }
                                act->encap_md = encap;
+                               list_add_tail(&act->encap_user, &encap->users);
                                act->dest_mport = encap->dest_mport;
                                act->deliver = 1;
                                rc = efx_mae_alloc_action_set(efx, act);
@@ -1123,6 +1126,7 @@ static int efx_tc_flower_replace(struct efx_nic *efx,
                                        goto release;
                                }
                                list_add_tail(&act->list, &rule->acts.list);
+                               act->user = &rule->acts;
                                act = NULL;
                                if (fa->id == FLOW_ACTION_REDIRECT)
                                        break; /* end of the line */
index 5a8f701..607429f 100644 (file)
@@ -36,6 +36,8 @@ struct efx_tc_action_set {
        __be16 vlan_proto[2]; /* Ethertypes for vlan_push */
        struct efx_tc_counter_index *count;
        struct efx_tc_encap_action *encap_md; /* entry in tc_encap_ht table */
+       struct list_head encap_user; /* entry on encap_md->users list */
+       struct efx_tc_action_set_list *user; /* Only populated if encap_md */
        u32 dest_mport;
        u32 fw_id; /* index of this entry in firmware actions table */
        struct list_head list;
@@ -151,6 +153,7 @@ enum efx_tc_rule_prios {
  * @encap_ht: Hashtable of TC encap actions
  * @encap_match_ht: Hashtable of TC encap matches
  * @match_action_ht: Hashtable of TC match-action rules
+ * @neigh_ht: Hashtable of neighbour watches (&struct efx_neigh_binder)
  * @reps_mport_id: MAE port allocated for representor RX
  * @reps_filter_uc: VNIC filter for representor unicast RX (promisc)
  * @reps_filter_mc: VNIC filter for representor multicast RX (allmulti)
@@ -181,6 +184,7 @@ struct efx_tc_state {
        struct rhashtable encap_ht;
        struct rhashtable encap_match_ht;
        struct rhashtable match_action_ht;
+       struct rhashtable neigh_ht;
        u32 reps_mport_id, reps_mport_vport_id;
        s32 reps_filter_uc, reps_filter_mc;
        bool flush_counters;
@@ -201,6 +205,9 @@ struct efx_tc_state {
 struct efx_rep;
 
 enum efx_encap_type efx_tc_indr_netdev_type(struct net_device *net_dev);
+struct efx_rep *efx_tc_flower_lookup_efv(struct efx_nic *efx,
+                                        struct net_device *dev);
+s64 efx_tc_flower_external_mport(struct efx_nic *efx, struct efx_rep *efv);
 int efx_tc_configure_default_rule_rep(struct efx_rep *efv);
 void efx_tc_deconfigure_default_rule(struct efx_nic *efx,
                                     struct efx_tc_flow_rule *rule);
index c18d645..1b79c53 100644 (file)
@@ -10,6 +10,7 @@
 
 #include "tc_bindings.h"
 #include "tc.h"
+#include "tc_encap_actions.h"
 
 struct efx_tc_block_binding {
        struct list_head list;
@@ -226,3 +227,15 @@ int efx_tc_setup(struct net_device *net_dev, enum tc_setup_type type,
 
        return -EOPNOTSUPP;
 }
+
+int efx_tc_netdev_event(struct efx_nic *efx, unsigned long event,
+                       struct net_device *net_dev)
+{
+       if (efx->type->is_vf)
+               return NOTIFY_DONE;
+
+       if (event == NETDEV_UNREGISTER)
+               efx_tc_unregister_egdev(efx, net_dev);
+
+       return NOTIFY_OK;
+}
index c210bb0..095ddeb 100644 (file)
@@ -26,4 +26,6 @@ int efx_tc_indr_setup_cb(struct net_device *net_dev, struct Qdisc *sch,
                         void *cb_priv, enum tc_setup_type type,
                         void *type_data, void *data,
                         void (*cleanup)(struct flow_block_cb *block_cb));
+int efx_tc_netdev_event(struct efx_nic *efx, unsigned long event,
+                       struct net_device *net_dev);
 #endif /* EFX_TC_BINDINGS_H */
index c41493e..c1bd7d4 100644 (file)
 #include "mae.h"
 #include <net/vxlan.h>
 #include <net/geneve.h>
+#include <net/netevent.h>
+#include <net/arp.h>
+
+static const struct rhashtable_params efx_neigh_ht_params = {
+       .key_len        = offsetof(struct efx_neigh_binder, ha),
+       .key_offset     = 0,
+       .head_offset    = offsetof(struct efx_neigh_binder, linkage),
+};
 
 static const struct rhashtable_params efx_tc_encap_ht_params = {
        .key_len        = offsetofend(struct efx_tc_encap_action, key),
@@ -28,9 +36,32 @@ static void efx_tc_encap_free(void *ptr, void *__unused)
        kfree(enc);
 }
 
+static void efx_neigh_free(void *ptr, void *__unused)
+{
+       struct efx_neigh_binder *neigh = ptr;
+
+       WARN_ON(refcount_read(&neigh->ref));
+       WARN_ON(!list_empty(&neigh->users));
+       put_net_track(neigh->net, &neigh->ns_tracker);
+       netdev_put(neigh->egdev, &neigh->dev_tracker);
+       kfree(neigh);
+}
+
 int efx_tc_init_encap_actions(struct efx_nic *efx)
 {
-       return rhashtable_init(&efx->tc->encap_ht, &efx_tc_encap_ht_params);
+       int rc;
+
+       rc = rhashtable_init(&efx->tc->neigh_ht, &efx_neigh_ht_params);
+       if (rc < 0)
+               goto fail_neigh_ht;
+       rc = rhashtable_init(&efx->tc->encap_ht, &efx_tc_encap_ht_params);
+       if (rc < 0)
+               goto fail_encap_ht;
+       return 0;
+fail_encap_ht:
+       rhashtable_destroy(&efx->tc->neigh_ht);
+fail_neigh_ht:
+       return rc;
 }
 
 /* Only call this in init failure teardown.
@@ -39,11 +70,337 @@ int efx_tc_init_encap_actions(struct efx_nic *efx)
 void efx_tc_destroy_encap_actions(struct efx_nic *efx)
 {
        rhashtable_destroy(&efx->tc->encap_ht);
+       rhashtable_destroy(&efx->tc->neigh_ht);
 }
 
 void efx_tc_fini_encap_actions(struct efx_nic *efx)
 {
        rhashtable_free_and_destroy(&efx->tc->encap_ht, efx_tc_encap_free, NULL);
+       rhashtable_free_and_destroy(&efx->tc->neigh_ht, efx_neigh_free, NULL);
+}
+
+static void efx_neigh_update(struct work_struct *work);
+
+static int efx_bind_neigh(struct efx_nic *efx,
+                         struct efx_tc_encap_action *encap, struct net *net,
+                         struct netlink_ext_ack *extack)
+{
+       struct efx_neigh_binder *neigh, *old;
+       struct flowi6 flow6 = {};
+       struct flowi4 flow4 = {};
+       int rc;
+
+       /* GCC stupidly thinks that only values explicitly listed in the enum
+        * definition can _possibly_ be sensible case values, so without this
+        * cast it complains about the IPv6 versions.
+        */
+       switch ((int)encap->type) {
+       case EFX_ENCAP_TYPE_VXLAN:
+       case EFX_ENCAP_TYPE_GENEVE:
+               flow4.flowi4_proto = IPPROTO_UDP;
+               flow4.fl4_dport = encap->key.tp_dst;
+               flow4.flowi4_tos = encap->key.tos;
+               flow4.daddr = encap->key.u.ipv4.dst;
+               flow4.saddr = encap->key.u.ipv4.src;
+               break;
+       case EFX_ENCAP_TYPE_VXLAN | EFX_ENCAP_FLAG_IPV6:
+       case EFX_ENCAP_TYPE_GENEVE | EFX_ENCAP_FLAG_IPV6:
+               flow6.flowi6_proto = IPPROTO_UDP;
+               flow6.fl6_dport = encap->key.tp_dst;
+               flow6.flowlabel = ip6_make_flowinfo(encap->key.tos,
+                                                   encap->key.label);
+               flow6.daddr = encap->key.u.ipv6.dst;
+               flow6.saddr = encap->key.u.ipv6.src;
+               break;
+       default:
+               NL_SET_ERR_MSG_FMT_MOD(extack, "Unsupported encap type %d",
+                                      (int)encap->type);
+               return -EOPNOTSUPP;
+       }
+
+       neigh = kzalloc(sizeof(*neigh), GFP_KERNEL_ACCOUNT);
+       if (!neigh)
+               return -ENOMEM;
+       neigh->net = get_net_track(net, &neigh->ns_tracker, GFP_KERNEL_ACCOUNT);
+       neigh->dst_ip = flow4.daddr;
+       neigh->dst_ip6 = flow6.daddr;
+
+       old = rhashtable_lookup_get_insert_fast(&efx->tc->neigh_ht,
+                                               &neigh->linkage,
+                                               efx_neigh_ht_params);
+       if (old) {
+               /* don't need our new entry */
+               put_net_track(neigh->net, &neigh->ns_tracker);
+               kfree(neigh);
+               if (!refcount_inc_not_zero(&old->ref))
+                       return -EAGAIN;
+               /* existing entry found, ref taken */
+               neigh = old;
+       } else {
+               /* New entry.  We need to initiate a lookup */
+               struct neighbour *n;
+               struct rtable *rt;
+
+               if (encap->type & EFX_ENCAP_FLAG_IPV6) {
+#if IS_ENABLED(CONFIG_IPV6)
+                       struct dst_entry *dst;
+
+                       dst = ipv6_stub->ipv6_dst_lookup_flow(net, NULL, &flow6,
+                                                             NULL);
+                       rc = PTR_ERR_OR_ZERO(dst);
+                       if (rc) {
+                               NL_SET_ERR_MSG_MOD(extack, "Failed to lookup route for IPv6 encap");
+                               goto out_free;
+                       }
+                       neigh->egdev = dst->dev;
+                       netdev_hold(neigh->egdev, &neigh->dev_tracker,
+                                   GFP_KERNEL_ACCOUNT);
+                       neigh->ttl = ip6_dst_hoplimit(dst);
+                       n = dst_neigh_lookup(dst, &flow6.daddr);
+                       dst_release(dst);
+#else
+                       /* We shouldn't ever get here, because if IPv6 isn't
+                        * enabled how did someone create an IPv6 tunnel_key?
+                        */
+                       rc = -EOPNOTSUPP;
+                       NL_SET_ERR_MSG_MOD(extack, "No IPv6 support (neigh bind)");
+#endif
+               } else {
+                       rt = ip_route_output_key(net, &flow4);
+                       if (IS_ERR_OR_NULL(rt)) {
+                               rc = PTR_ERR_OR_ZERO(rt);
+                               if (!rc)
+                                       rc = -EIO;
+                               NL_SET_ERR_MSG_MOD(extack, "Failed to lookup route for encap");
+                               goto out_free;
+                       }
+                       neigh->egdev = rt->dst.dev;
+                       netdev_hold(neigh->egdev, &neigh->dev_tracker,
+                                   GFP_KERNEL_ACCOUNT);
+                       neigh->ttl = ip4_dst_hoplimit(&rt->dst);
+                       n = dst_neigh_lookup(&rt->dst, &flow4.daddr);
+                       ip_rt_put(rt);
+               }
+               if (!n) {
+                       rc = -ENETUNREACH;
+                       NL_SET_ERR_MSG_MOD(extack, "Failed to lookup neighbour for encap");
+                       netdev_put(neigh->egdev, &neigh->dev_tracker);
+                       goto out_free;
+               }
+               refcount_set(&neigh->ref, 1);
+               INIT_LIST_HEAD(&neigh->users);
+               read_lock_bh(&n->lock);
+               ether_addr_copy(neigh->ha, n->ha);
+               neigh->n_valid = n->nud_state & NUD_VALID;
+               read_unlock_bh(&n->lock);
+               rwlock_init(&neigh->lock);
+               INIT_WORK(&neigh->work, efx_neigh_update);
+               neigh->efx = efx;
+               neigh->used = jiffies;
+               if (!neigh->n_valid)
+                       /* Prod ARP to find us a neighbour */
+                       neigh_event_send(n, NULL);
+               neigh_release(n);
+       }
+       /* Add us to this neigh */
+       encap->neigh = neigh;
+       list_add_tail(&encap->list, &neigh->users);
+       return 0;
+
+out_free:
+       /* cleanup common to several error paths */
+       rhashtable_remove_fast(&efx->tc->neigh_ht, &neigh->linkage,
+                              efx_neigh_ht_params);
+       synchronize_rcu();
+       put_net_track(net, &neigh->ns_tracker);
+       kfree(neigh);
+       return rc;
+}
+
+static void efx_free_neigh(struct efx_neigh_binder *neigh)
+{
+       struct efx_nic *efx = neigh->efx;
+
+       rhashtable_remove_fast(&efx->tc->neigh_ht, &neigh->linkage,
+                              efx_neigh_ht_params);
+       synchronize_rcu();
+       netdev_put(neigh->egdev, &neigh->dev_tracker);
+       put_net_track(neigh->net, &neigh->ns_tracker);
+       kfree(neigh);
+}
+
+static void efx_release_neigh(struct efx_nic *efx,
+                             struct efx_tc_encap_action *encap)
+{
+       struct efx_neigh_binder *neigh = encap->neigh;
+
+       if (!neigh)
+               return;
+       list_del(&encap->list);
+       encap->neigh = NULL;
+       if (!refcount_dec_and_test(&neigh->ref))
+               return; /* still in use */
+       efx_free_neigh(neigh);
+}
+
+static void efx_gen_encap_header(struct efx_tc_encap_action *encap)
+{
+       /* stub for now */
+       encap->n_valid = false;
+       memset(encap->encap_hdr, 0, sizeof(encap->encap_hdr));
+       encap->encap_hdr_len = ETH_HLEN;
+}
+
+static void efx_tc_update_encap(struct efx_nic *efx,
+                               struct efx_tc_encap_action *encap)
+{
+       struct efx_tc_action_set_list *acts, *fallback;
+       struct efx_tc_flow_rule *rule;
+       struct efx_tc_action_set *act;
+       int rc;
+
+       if (encap->n_valid) {
+               /* Make sure no rules are using this encap while we change it */
+               list_for_each_entry(act, &encap->users, encap_user) {
+                       acts = act->user;
+                       if (WARN_ON(!acts)) /* can't happen */
+                               continue;
+                       rule = container_of(acts, struct efx_tc_flow_rule, acts);
+                       if (rule->fallback)
+                               fallback = rule->fallback;
+                       else /* fallback fallback: deliver to PF */
+                               fallback = &efx->tc->facts.pf;
+                       rc = efx_mae_update_rule(efx, fallback->fw_id,
+                                                rule->fw_id);
+                       if (rc)
+                               netif_err(efx, drv, efx->net_dev,
+                                         "Failed to update (f) rule %08x rc %d\n",
+                                         rule->fw_id, rc);
+                       else
+                               netif_dbg(efx, drv, efx->net_dev, "Updated (f) rule %08x\n",
+                                         rule->fw_id);
+               }
+       }
+
+       if (encap->neigh) {
+               read_lock_bh(&encap->neigh->lock);
+               efx_gen_encap_header(encap);
+               read_unlock_bh(&encap->neigh->lock);
+       } else {
+               encap->n_valid = false;
+               memset(encap->encap_hdr, 0, sizeof(encap->encap_hdr));
+               encap->encap_hdr_len = ETH_HLEN;
+       }
+
+       rc = efx_mae_update_encap_md(efx, encap);
+       if (rc) {
+               netif_err(efx, drv, efx->net_dev,
+                         "Failed to update encap hdr %08x rc %d\n",
+                         encap->fw_id, rc);
+               return;
+       }
+       netif_dbg(efx, drv, efx->net_dev, "Updated encap hdr %08x\n",
+                 encap->fw_id);
+       if (!encap->n_valid)
+               return;
+       /* Update rule users: use the action if they are now ready */
+       list_for_each_entry(act, &encap->users, encap_user) {
+               acts = act->user;
+               if (WARN_ON(!acts)) /* can't happen */
+                       continue;
+               rule = container_of(acts, struct efx_tc_flow_rule, acts);
+               if (!efx_tc_check_ready(efx, rule))
+                       continue;
+               rc = efx_mae_update_rule(efx, acts->fw_id, rule->fw_id);
+               if (rc)
+                       netif_err(efx, drv, efx->net_dev,
+                                 "Failed to update rule %08x rc %d\n",
+                                 rule->fw_id, rc);
+               else
+                       netif_dbg(efx, drv, efx->net_dev, "Updated rule %08x\n",
+                                 rule->fw_id);
+       }
+}
+
+static void efx_neigh_update(struct work_struct *work)
+{
+       struct efx_neigh_binder *neigh = container_of(work, struct efx_neigh_binder, work);
+       struct efx_tc_encap_action *encap;
+       struct efx_nic *efx = neigh->efx;
+
+       mutex_lock(&efx->tc->mutex);
+       list_for_each_entry(encap, &neigh->users, list)
+               efx_tc_update_encap(neigh->efx, encap);
+       /* release ref taken in efx_neigh_event() */
+       if (refcount_dec_and_test(&neigh->ref))
+               efx_free_neigh(neigh);
+       mutex_unlock(&efx->tc->mutex);
+}
+
+static int efx_neigh_event(struct efx_nic *efx, struct neighbour *n)
+{
+       struct efx_neigh_binder keys = {NULL}, *neigh;
+       bool n_valid, ipv6 = false;
+       char ha[ETH_ALEN];
+       size_t keysize;
+
+       if (WARN_ON(!efx->tc))
+               return NOTIFY_DONE;
+
+       if (n->tbl == &arp_tbl) {
+               keysize = sizeof(keys.dst_ip);
+#if IS_ENABLED(CONFIG_IPV6)
+       } else if (n->tbl == ipv6_stub->nd_tbl) {
+               ipv6 = true;
+               keysize = sizeof(keys.dst_ip6);
+#endif
+       } else {
+               return NOTIFY_DONE;
+       }
+       if (!n->parms) {
+               netif_warn(efx, drv, efx->net_dev, "neigh_event with no parms!\n");
+               return NOTIFY_DONE;
+       }
+       keys.net = read_pnet(&n->parms->net);
+       if (n->tbl->key_len != keysize) {
+               netif_warn(efx, drv, efx->net_dev, "neigh_event with bad key_len %u\n",
+                          n->tbl->key_len);
+               return NOTIFY_DONE;
+       }
+       read_lock_bh(&n->lock); /* Get a consistent view */
+       memcpy(ha, n->ha, ETH_ALEN);
+       n_valid = (n->nud_state & NUD_VALID) && !n->dead;
+       read_unlock_bh(&n->lock);
+       if (ipv6)
+               memcpy(&keys.dst_ip6, n->primary_key, n->tbl->key_len);
+       else
+               memcpy(&keys.dst_ip, n->primary_key, n->tbl->key_len);
+       rcu_read_lock();
+       neigh = rhashtable_lookup_fast(&efx->tc->neigh_ht, &keys,
+                                      efx_neigh_ht_params);
+       if (!neigh || neigh->dying)
+               /* We're not interested in this neighbour */
+               goto done;
+       write_lock_bh(&neigh->lock);
+       if (n_valid == neigh->n_valid && !memcmp(ha, neigh->ha, ETH_ALEN)) {
+               write_unlock_bh(&neigh->lock);
+               /* Nothing has changed; no work to do */
+               goto done;
+       }
+       neigh->n_valid = n_valid;
+       memcpy(neigh->ha, ha, ETH_ALEN);
+       write_unlock_bh(&neigh->lock);
+       if (refcount_inc_not_zero(&neigh->ref)) {
+               rcu_read_unlock();
+               if (!schedule_work(&neigh->work))
+                       /* failed to schedule, release the ref we just took */
+                       if (refcount_dec_and_test(&neigh->ref))
+                               efx_free_neigh(neigh);
+       } else {
+done:
+               rcu_read_unlock();
+       }
+       return NOTIFY_DONE;
 }
 
 bool efx_tc_check_ready(struct efx_nic *efx, struct efx_tc_flow_rule *rule)
@@ -54,7 +411,7 @@ bool efx_tc_check_ready(struct efx_nic *efx, struct efx_tc_flow_rule *rule)
         * neighbour info for the outer Ethernet header.
         */
        list_for_each_entry(act, &rule->acts.list, list)
-               if (act->encap_md) /* neigh bindings not implemented yet */
+               if (act->encap_md && !act->encap_md->n_valid)
                        return false;
        return true;
 }
@@ -65,6 +422,7 @@ struct efx_tc_encap_action *efx_tc_flower_create_encap_md(
 {
        enum efx_encap_type type = efx_tc_indr_netdev_type(egdev);
        struct efx_tc_encap_action *encap, *old;
+       struct efx_rep *to_efv;
        s64 rc;
 
        if (type == EFX_ENCAP_TYPE_NONE) {
@@ -98,6 +456,7 @@ struct efx_tc_encap_action *efx_tc_flower_create_encap_md(
                return ERR_PTR(-ENOMEM);
        encap->type = type;
        encap->key = info->key;
+       INIT_LIST_HEAD(&encap->users);
        old = rhashtable_lookup_get_insert_fast(&efx->tc->encap_ht,
                                                &encap->linkage,
                                                efx_tc_encap_ht_params);
@@ -110,9 +469,42 @@ struct efx_tc_encap_action *efx_tc_flower_create_encap_md(
                return old;
        }
 
+       rc = efx_bind_neigh(efx, encap, dev_net(egdev), extack);
+       if (rc < 0)
+               goto out_remove;
+       to_efv = efx_tc_flower_lookup_efv(efx, encap->neigh->egdev);
+       if (IS_ERR(to_efv)) {
+               /* neigh->egdev isn't ours */
+               NL_SET_ERR_MSG_MOD(extack, "Tunnel egress device not on switch");
+               rc = PTR_ERR(to_efv);
+               goto out_release;
+       }
+       rc = efx_tc_flower_external_mport(efx, to_efv);
+       if (rc < 0) {
+               NL_SET_ERR_MSG_MOD(extack, "Failed to identify tunnel egress m-port");
+               goto out_release;
+       }
+       encap->dest_mport = rc;
+       read_lock_bh(&encap->neigh->lock);
+       efx_gen_encap_header(encap);
+       read_unlock_bh(&encap->neigh->lock);
+
+       rc = efx_mae_allocate_encap_md(efx, encap);
+       if (rc < 0) {
+               NL_SET_ERR_MSG_MOD(extack, "Failed to write tunnel header to hw");
+               goto out_release;
+       }
+
        /* ref and return */
        refcount_set(&encap->ref, 1);
        return encap;
+out_release:
+       efx_release_neigh(efx, encap);
+out_remove:
+       rhashtable_remove_fast(&efx->tc->encap_ht, &encap->linkage,
+                              efx_tc_encap_ht_params);
+       kfree(encap);
+       return ERR_PTR(rc);
 }
 
 void efx_tc_flower_release_encap_md(struct efx_nic *efx,
@@ -120,7 +512,59 @@ void efx_tc_flower_release_encap_md(struct efx_nic *efx,
 {
        if (!refcount_dec_and_test(&encap->ref))
                return; /* still in use */
+       efx_release_neigh(efx, encap);
        rhashtable_remove_fast(&efx->tc->encap_ht, &encap->linkage,
                               efx_tc_encap_ht_params);
+       efx_mae_free_encap_md(efx, encap);
        kfree(encap);
 }
+
+static void efx_tc_remove_neigh_users(struct efx_nic *efx, struct efx_neigh_binder *neigh)
+{
+       struct efx_tc_encap_action *encap, *next;
+
+       list_for_each_entry_safe(encap, next, &neigh->users, list) {
+               /* Should cause neigh usage count to fall to zero, freeing it */
+               efx_release_neigh(efx, encap);
+               /* The encap has lost its neigh, so it's now unready */
+               efx_tc_update_encap(efx, encap);
+       }
+}
+
+void efx_tc_unregister_egdev(struct efx_nic *efx, struct net_device *net_dev)
+{
+       struct efx_neigh_binder *neigh;
+       struct rhashtable_iter walk;
+
+       mutex_lock(&efx->tc->mutex);
+       rhashtable_walk_enter(&efx->tc->neigh_ht, &walk);
+       rhashtable_walk_start(&walk);
+       while ((neigh = rhashtable_walk_next(&walk)) != NULL) {
+               if (IS_ERR(neigh))
+                       continue;
+               if (neigh->egdev != net_dev)
+                       continue;
+               neigh->dying = true;
+               rhashtable_walk_stop(&walk);
+               synchronize_rcu(); /* Make sure any updates see dying flag */
+               efx_tc_remove_neigh_users(efx, neigh); /* might sleep */
+               rhashtable_walk_start(&walk);
+       }
+       rhashtable_walk_stop(&walk);
+       rhashtable_walk_exit(&walk);
+       mutex_unlock(&efx->tc->mutex);
+}
+
+int efx_tc_netevent_event(struct efx_nic *efx, unsigned long event,
+                         void *ptr)
+{
+       if (efx->type->is_vf)
+               return NOTIFY_DONE;
+
+       switch (event) {
+       case NETEVENT_NEIGH_UPDATE:
+               return efx_neigh_event(efx, ptr);
+       default:
+               return NOTIFY_DONE;
+       }
+}
index 1a3679e..4d755fb 100644 (file)
 #include <linux/refcount.h>
 #include <net/tc_act/tc_tunnel_key.h>
 
+/**
+ * struct efx_neigh_binder - driver state for a neighbour entry
+ * @net: the network namespace in which this neigh resides
+ * @dst_ip: the IPv4 destination address resolved by this neigh
+ * @dst_ip6: the IPv6 destination address resolved by this neigh
+ * @ha: the hardware (Ethernet) address of the neighbour
+ * @n_valid: true if the neighbour is in NUD_VALID state
+ * @lock: protects @ha and @n_valid
+ * @ttl: Time To Live associated with the route used
+ * @dying: set when egdev is going away, to skip further updates
+ * @egdev: egress device from the route lookup.  Holds a reference
+ * @dev_tracker: reference tracker entry for @egdev
+ * @ns_tracker: reference tracker entry for @ns
+ * @ref: counts encap actions referencing this entry
+ * @used: jiffies of last time traffic hit any encap action using this.
+ *      When counter reads update this, a new neighbour event is sent to
+ *      indicate that the neighbour entry is still in use.
+ * @users: list of &struct efx_tc_encap_action
+ * @linkage: entry in efx->neigh_ht (keys are @net, @dst_ip, @dst_ip6).
+ * @work: processes neighbour state changes, updates the encap actions
+ * @efx: owning NIC instance.
+ *
+ * Associates a neighbour entry with the encap actions that are
+ * interested in it, allowing the latter to be updated when the
+ * neighbour details change.
+ * Whichever of @dst_ip and @dst_ip6 is not in use will be all-zeroes,
+ * this distinguishes IPv4 from IPv6 entries.
+ */
+struct efx_neigh_binder {
+       struct net *net;
+       __be32 dst_ip;
+       struct in6_addr dst_ip6;
+       char ha[ETH_ALEN];
+       bool n_valid;
+       rwlock_t lock;
+       u8 ttl;
+       bool dying;
+       struct net_device *egdev;
+       netdevice_tracker dev_tracker;
+       netns_tracker ns_tracker;
+       refcount_t ref;
+       unsigned long used;
+       struct list_head users;
+       struct rhash_head linkage;
+       struct work_struct work;
+       struct efx_nic *efx;
+};
+
 /* This limit is arbitrary; current hardware (SN1022) handles encap headers
  * of up to 126 bytes, but that limit is not enshrined in the MCDI protocol.
  */
@@ -24,7 +72,11 @@ struct efx_tc_encap_action {
        struct ip_tunnel_key key; /* 52 bytes */
        u32 dest_mport; /* is copied into struct efx_tc_action_set */
        u8 encap_hdr_len;
+       bool n_valid;
        u8 encap_hdr[EFX_TC_MAX_ENCAP_HDR];
+       struct efx_neigh_binder *neigh;
+       struct list_head list; /* entry on neigh->users list */
+       struct list_head users; /* action sets using this encap_md */
        struct rhash_head linkage; /* efx->tc_encap_ht */
        refcount_t ref;
        u32 fw_id; /* index of this entry in firmware encap table */
@@ -44,4 +96,8 @@ struct efx_tc_encap_action *efx_tc_flower_create_encap_md(
 void efx_tc_flower_release_encap_md(struct efx_nic *efx,
                                    struct efx_tc_encap_action *encap);
 
+void efx_tc_unregister_egdev(struct efx_nic *efx, struct net_device *net_dev);
+int efx_tc_netevent_event(struct efx_nic *efx, unsigned long event,
+                         void *ptr);
+
 #endif /* EFX_TC_ENCAP_ACTIONS_H */