sfc: add a hashtable for offloaded TC rules

Nothing inserts into this table yet, but we have code to remove rules
 on FLOW_CLS_DESTROY or at driver teardown time, in both cases also
 attempting to remove the corresponding hardware rules.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/sfc/ef100_rep.c b/drivers/net/ethernet/sfc/ef100_rep.c
index 0a631e0..869f806 100644 (file)
--- a/drivers/net/ethernet/sfc/ef100_rep.c
+++ b/drivers/net/ethernet/sfc/ef100_rep.c
@@ -135,7 +135,7 @@ static void efx_ef100_rep_get_stats64(struct net_device *dev,
        stats->tx_errors = atomic64_read(&efv->stats.tx_errors);
 }
 
-static const struct net_device_ops efx_ef100_rep_netdev_ops = {
+const struct net_device_ops efx_ef100_rep_netdev_ops = {
        .ndo_open               = efx_ef100_rep_open,
        .ndo_stop               = efx_ef100_rep_close,
        .ndo_start_xmit         = efx_ef100_rep_xmit,

diff --git a/drivers/net/ethernet/sfc/ef100_rep.h b/drivers/net/ethernet/sfc/ef100_rep.h
index 070f700..c21bc71 100644 (file)
--- a/drivers/net/ethernet/sfc/ef100_rep.h
+++ b/drivers/net/ethernet/sfc/ef100_rep.h
@@ -66,4 +66,5 @@ void efx_ef100_rep_rx_packet(struct efx_rep *efv, struct efx_rx_buffer *rx_buf);
  * Caller must hold rcu_read_lock().
  */
 struct efx_rep *efx_ef100_find_rep_by_mport(struct efx_nic *efx, u16 mport);
+extern const struct net_device_ops efx_ef100_rep_netdev_ops;
 #endif /* EF100_REP_H */

diff --git a/drivers/net/ethernet/sfc/tc.c b/drivers/net/ethernet/sfc/tc.c
index cb7f76c..08e2af6 100644 (file)
--- a/drivers/net/ethernet/sfc/tc.c
+++ b/drivers/net/ethernet/sfc/tc.c
@@ -15,6 +15,39 @@
 #include "ef100_rep.h"
 #include "efx.h"
 
+#define EFX_EFV_PF     NULL
+/* Look up the representor information (efv) for a device.
+ * 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 *efv;
+
+       if (!dev)
+               return ERR_PTR(-EOPNOTSUPP);
+       /* Is it us (the PF)? */
+       if (dev == efx->net_dev)
+               return EFX_EFV_PF;
+       /* Is it an efx vfrep at all? */
+       if (dev->netdev_ops != &efx_ef100_rep_netdev_ops)
+               return ERR_PTR(-EOPNOTSUPP);
+       /* Is it ours?  We don't support TC rules that include another
+        * EF100's netdevices (not even on another port of the same NIC).
+        */
+       efv = netdev_priv(dev);
+       if (efv->parent != efx)
+               return ERR_PTR(-EOPNOTSUPP);
+       return efv;
+}
+
+static const struct rhashtable_params efx_tc_match_action_ht_params = {
+       .key_len        = sizeof(unsigned long),
+       .key_offset     = offsetof(struct efx_tc_flow_rule, cookie),
+       .head_offset    = offsetof(struct efx_tc_flow_rule, linkage),
+};
+
 static void efx_tc_free_action_set(struct efx_nic *efx,
                                   struct efx_tc_action_set *act, bool in_hw)
 {
@@ -59,10 +92,74 @@ static void efx_tc_delete_rule(struct efx_nic *efx, struct efx_tc_flow_rule *rul
        rule->fw_id = MC_CMD_MAE_ACTION_RULE_INSERT_OUT_ACTION_RULE_ID_NULL;
 }
 
+static void efx_tc_flow_free(void *ptr, void *arg)
+{
+       struct efx_tc_flow_rule *rule = ptr;
+       struct efx_nic *efx = arg;
+
+       netif_err(efx, drv, efx->net_dev,
+                 "tc rule %lx still present at teardown, removing\n",
+                 rule->cookie);
+
+       efx_mae_delete_rule(efx, rule->fw_id);
+
+       /* Release entries in subsidiary tables */
+       efx_tc_free_action_set_list(efx, &rule->acts, true);
+
+       kfree(rule);
+}
+
+static int efx_tc_flower_destroy(struct efx_nic *efx,
+                                struct net_device *net_dev,
+                                struct flow_cls_offload *tc)
+{
+       struct netlink_ext_ack *extack = tc->common.extack;
+       struct efx_tc_flow_rule *rule;
+
+       rule = rhashtable_lookup_fast(&efx->tc->match_action_ht, &tc->cookie,
+                                     efx_tc_match_action_ht_params);
+       if (!rule) {
+               /* Only log a message if we're the ingress device.  Otherwise
+                * it's a foreign filter and we might just not have been
+                * interested (e.g. we might not have been the egress device
+                * either).
+                */
+               if (!IS_ERR(efx_tc_flower_lookup_efv(efx, net_dev)))
+                       netif_warn(efx, drv, efx->net_dev,
+                                  "Filter %lx not found to remove\n", tc->cookie);
+               NL_SET_ERR_MSG_MOD(extack, "Flow cookie not found in offloaded rules");
+               return -ENOENT;
+       }
+
+       /* Remove it from HW */
+       efx_tc_delete_rule(efx, rule);
+       /* Delete it from SW */
+       rhashtable_remove_fast(&efx->tc->match_action_ht, &rule->linkage,
+                              efx_tc_match_action_ht_params);
+       netif_dbg(efx, drv, efx->net_dev, "Removed filter %lx\n", rule->cookie);
+       kfree(rule);
+       return 0;
+}
+
 int efx_tc_flower(struct efx_nic *efx, struct net_device *net_dev,
                  struct flow_cls_offload *tc, struct efx_rep *efv)
 {
-       return -EOPNOTSUPP;
+       int rc;
+
+       if (!efx->tc)
+               return -EOPNOTSUPP;
+
+       mutex_lock(&efx->tc->mutex);
+       switch (tc->command) {
+       case FLOW_CLS_DESTROY:
+               rc = efx_tc_flower_destroy(efx, net_dev, tc);
+               break;
+       default:
+               rc = -EOPNOTSUPP;
+               break;
+       }
+       mutex_unlock(&efx->tc->mutex);
+       return rc;
 }
 
 static int efx_tc_configure_default_rule(struct efx_nic *efx, u32 ing_port,
@@ -239,6 +336,8 @@ void efx_fini_tc(struct efx_nic *efx)
 
 int efx_init_struct_tc(struct efx_nic *efx)
 {
+       int rc;
+
        if (efx->type->is_vf)
                return 0;
 
@@ -247,6 +346,10 @@ int efx_init_struct_tc(struct efx_nic *efx)
                return -ENOMEM;
        INIT_LIST_HEAD(&efx->tc->block_list);
 
+       mutex_init(&efx->tc->mutex);
+       rc = rhashtable_init(&efx->tc->match_action_ht, &efx_tc_match_action_ht_params);
+       if (rc < 0)
+               goto fail_match_action_ht;
        efx->tc->reps_filter_uc = -1;
        efx->tc->reps_filter_mc = -1;
        INIT_LIST_HEAD(&efx->tc->dflt.pf.acts.list);
@@ -254,6 +357,11 @@ int efx_init_struct_tc(struct efx_nic *efx)
        INIT_LIST_HEAD(&efx->tc->dflt.wire.acts.list);
        efx->tc->dflt.wire.fw_id = MC_CMD_MAE_ACTION_RULE_INSERT_OUT_ACTION_RULE_ID_NULL;
        return 0;
+fail_match_action_ht:
+       mutex_destroy(&efx->tc->mutex);
+       kfree(efx->tc);
+       efx->tc = NULL;
+       return rc;
 }
 
 void efx_fini_struct_tc(struct efx_nic *efx)
@@ -261,10 +369,15 @@ void efx_fini_struct_tc(struct efx_nic *efx)
        if (!efx->tc)
                return;
 
+       mutex_lock(&efx->tc->mutex);
        EFX_WARN_ON_PARANOID(efx->tc->dflt.pf.fw_id !=
                             MC_CMD_MAE_ACTION_RULE_INSERT_OUT_ACTION_RULE_ID_NULL);
        EFX_WARN_ON_PARANOID(efx->tc->dflt.wire.fw_id !=
                             MC_CMD_MAE_ACTION_RULE_INSERT_OUT_ACTION_RULE_ID_NULL);
+       rhashtable_free_and_destroy(&efx->tc->match_action_ht, efx_tc_flow_free,
+                                   efx);
+       mutex_unlock(&efx->tc->mutex);
+       mutex_destroy(&efx->tc->mutex);
        kfree(efx->tc);
        efx->tc = NULL;
 }

diff --git a/drivers/net/ethernet/sfc/tc.h b/drivers/net/ethernet/sfc/tc.h
index 3e2299c..94a0437 100644 (file)
--- a/drivers/net/ethernet/sfc/tc.h
+++ b/drivers/net/ethernet/sfc/tc.h
@@ -12,6 +12,7 @@
 #ifndef EFX_TC_H
 #define EFX_TC_H
 #include <net/flow_offload.h>
+#include <linux/rhashtable.h>
 #include "net_driver.h"
 
 /* Error reporting: convenience macros.  For indicating why a given filter
@@ -55,6 +56,8 @@ struct efx_tc_action_set_list {
 };
 
 struct efx_tc_flow_rule {
+       unsigned long cookie;
+       struct rhash_head linkage;
        struct efx_tc_match match;
        struct efx_tc_action_set_list acts;
        u32 fw_id;
@@ -69,6 +72,8 @@ enum efx_tc_rule_prios {
  * struct efx_tc_state - control plane data for TC offload
  *
  * @block_list: List of &struct efx_tc_block_binding
+ * @mutex: Used to serialise operations on TC hashtables
+ * @match_action_ht: Hashtable of TC match-action rules
  * @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)
@@ -81,6 +86,8 @@ enum efx_tc_rule_prios {
  */
 struct efx_tc_state {
        struct list_head block_list;
+       struct mutex mutex;
+       struct rhashtable match_action_ht;
        u32 reps_mport_id, reps_mport_vport_id;
        s32 reps_filter_uc, reps_filter_mc;
        struct {