net: sched: extend flow_action_entry with destructor

Generalize flow_action_entry cleanup by extending the structure with
pointer to destructor function. Set the destructor in
tc_setup_flow_action(). Refactor tc_cleanup_flow_action() to call
entry->destructor() instead of using switch that dispatches by entry->id
and manually executes cleanup.

This refactoring is necessary for following patches in this series that
require destructor to use tc_action->ops callbacks that can't be easily
obtained in tc_cleanup_flow_action().

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 50 insertions, 33 deletions

diff --git a/include/net/flow_offload.h b/include/net/flow_offload.h
index fc881875f856..86c567f531f3 100644
--- a/include/net/flow_offload.h
+++ b/include/net/flow_offload.h
@@ -154,8 +154,12 @@ enum flow_action_mangle_base {
         FLOW_ACT_MANGLE_HDR_TYPE_UDP,
 };
 
+typedef void (*action_destr)(void *priv);
+
 struct flow_action_entry {
         enum flow_action_id             id;
+        action_destr                    destructor;
+        void                            *destructor_priv;
         union {
                 u32                     chain_index;    /* FLOW_ACTION_GOTO */
                 struct net_device       *dev;           /* FLOW_ACTION_REDIRECT */
@@ -170,7 +174,7 @@ struct flow_action_entry {
                         u32             mask;
                         u32             val;
                 } mangle;
-                const struct ip_tunnel_info *tunnel;    /* FLOW_ACTION_TUNNEL_ENCAP */
+                struct ip_tunnel_info   *tunnel;        /* FLOW_ACTION_TUNNEL_ENCAP */
                 u32                     csum_flags;     /* FLOW_ACTION_CSUM */
                 u32                     mark;           /* FLOW_ACTION_MARK */
                 u16                     ptype;          /* FLOW_ACTION_PTYPE */
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 05c4fe1c3ca2..c668195379bd 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -3282,25 +3282,48 @@ void tc_cleanup_flow_action(struct flow_action *flow_action)
         struct flow_action_entry *entry;
         int i;
 
-        flow_action_for_each(i, entry, flow_action) {
-                switch (entry->id) {
-                case FLOW_ACTION_REDIRECT:
-                case FLOW_ACTION_MIRRED:
-                case FLOW_ACTION_REDIRECT_INGRESS:
-                case FLOW_ACTION_MIRRED_INGRESS:
-                        if (entry->dev)
-                                dev_put(entry->dev);
-                        break;
-                case FLOW_ACTION_TUNNEL_ENCAP:
-                        kfree(entry->tunnel);
-                        break;
-                default:
-                        break;
-                }
-        }
+        flow_action_for_each(i, entry, flow_action)
+                if (entry->destructor)
+                        entry->destructor(entry->destructor_priv);
 }
 EXPORT_SYMBOL(tc_cleanup_flow_action);
 
+static void tcf_mirred_put_dev(void *priv)
+{
+        struct net_device *dev = priv;
+
+        dev_put(dev);
+}
+
+static void tcf_mirred_get_dev(struct flow_action_entry *entry,
+                               const struct tc_action *act)
+{
+        entry->dev = tcf_mirred_dev(act);
+        if (!entry->dev)
+                return;
+        dev_hold(entry->dev);
+        entry->destructor = tcf_mirred_put_dev;
+        entry->destructor_priv = entry->dev;
+}
+
+static void tcf_tunnel_encap_put_tunnel(void *priv)
+{
+        struct ip_tunnel_info *tunnel = priv;
+
+        kfree(tunnel);
+}
+
+static int tcf_tunnel_encap_get_tunnel(struct flow_action_entry *entry,
+                                       const struct tc_action *act)
+{
+        entry->tunnel = tcf_tunnel_info_copy(act);
+        if (!entry->tunnel)
+                return -ENOMEM;
+        entry->destructor = tcf_tunnel_encap_put_tunnel;
+        entry->destructor_priv = entry->tunnel;
+        return 0;
+}
+
 int tc_setup_flow_action(struct flow_action *flow_action,
                          const struct tcf_exts *exts, bool rtnl_held)
 {
@@ -3329,24 +3352,16 @@ int tc_setup_flow_action(struct flow_action *flow_action,
                         entry->chain_index = tcf_gact_goto_chain_index(act);
                 } else if (is_tcf_mirred_egress_redirect(act)) {
                         entry->id = FLOW_ACTION_REDIRECT;
-                        entry->dev = tcf_mirred_dev(act);
-                        if (entry->dev)
-                                dev_hold(entry->dev);
+                        tcf_mirred_get_dev(entry, act);
                 } else if (is_tcf_mirred_egress_mirror(act)) {
                         entry->id = FLOW_ACTION_MIRRED;
-                        entry->dev = tcf_mirred_dev(act);
-                        if (entry->dev)
-                                dev_hold(entry->dev);
+                        tcf_mirred_get_dev(entry, act);
                 } else if (is_tcf_mirred_ingress_redirect(act)) {
                         entry->id = FLOW_ACTION_REDIRECT_INGRESS;
-                        entry->dev = tcf_mirred_dev(act);
-                        if (entry->dev)
-                                dev_hold(entry->dev);
+                        tcf_mirred_get_dev(entry, act);
                 } else if (is_tcf_mirred_ingress_mirror(act)) {
                         entry->id = FLOW_ACTION_MIRRED_INGRESS;
-                        entry->dev = tcf_mirred_dev(act);
-                        if (entry->dev)
-                                dev_hold(entry->dev);
+                        tcf_mirred_get_dev(entry, act);
                 } else if (is_tcf_vlan(act)) {
                         switch (tcf_vlan_action(act)) {
                         case TCA_VLAN_ACT_PUSH:
@@ -3370,11 +3385,9 @@ int tc_setup_flow_action(struct flow_action *flow_action,
                         }
                 } else if (is_tcf_tunnel_set(act)) {
                         entry->id = FLOW_ACTION_TUNNEL_ENCAP;
-                        entry->tunnel = tcf_tunnel_info_copy(act);
-                        if (!entry->tunnel) {
-                                err = -ENOMEM;
+                        err = tcf_tunnel_encap_get_tunnel(entry, act);
+                        if (err)
                                 goto err_out;
-                        }
                 } else if (is_tcf_tunnel_release(act)) {
                         entry->id = FLOW_ACTION_TUNNEL_DECAP;
                 } else if (is_tcf_pedit(act)) {