net_sched: move tc_action into tcf_common

struct tc_action is confusing, currently we use it for two purposes:
1) Pass in arguments and carry out results from helper functions
2) A generic representation for tc actions

The first one is error-prone, since we need to make sure we don't
miss anything. This patch aims to get rid of this use, by moving
tc_action into tcf_common, so that they are allocated together
in hashtable and can be cast'ed easily.

And together with the following patch, we could really make
tc_action a generic representation for all tc actions and each
type of action can inherit from it.

Cc: Jamal Hadi Salim <[email protected]>
Signed-off-by: Cong Wang <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: congwang

include/net/act_api.h

@@ -10,7 +10,26 @@
 #include <net/net_namespace.h>
 #include <net/netns/generic.h>
 
+
+struct tcf_hashinfo {
+	struct hlist_head	*htab;
+	unsigned int		hmask;
+	spinlock_t		lock;
+	u32			index;
+};
+
+struct tc_action_ops;
+
+struct tc_action {
+	const struct tc_action_ops	*ops;
+	__u32			type; /* for backward compat(TCA_OLD_COMPAT) */
+	__u32			order;
+	struct list_head	list;
+	struct tcf_hashinfo	*hinfo;
+};
+
 struct tcf_common {
+	struct tc_action		tcfc_act;
 	struct hlist_node		tcfc_head;
 	u32				tcfc_index;
 	int				tcfc_refcnt;
@@ -26,6 +45,7 @@ struct tcf_common {
 	struct gnet_stats_basic_cpu __percpu *cpu_bstats;
 	struct gnet_stats_queue __percpu *cpu_qstats;
 };
+#define tcf_act		common.tcfc_act
 #define tcf_head	common.tcfc_head
 #define tcf_index	common.tcfc_index
 #define tcf_refcnt	common.tcfc_refcnt
@@ -39,13 +59,6 @@ struct tcf_common {
 #define tcf_lock	common.tcfc_lock
 #define tcf_rcu		common.tcfc_rcu
 
-struct tcf_hashinfo {
-	struct hlist_head	*htab;
-	unsigned int		hmask;
-	spinlock_t		lock;
-	u32			index;
-};
-
 static inline unsigned int tcf_hash(u32 index, unsigned int hmask)
 {
 	return index & hmask;
@@ -88,15 +101,6 @@ static inline void tcf_tm_dump(struct tcf_t *dtm, const struct tcf_t *stm)
 	dtm->expires = jiffies_to_clock_t(stm->expires);
 }
 
-struct tc_action {
-	void			*priv;
-	const struct tc_action_ops	*ops;
-	__u32			type; /* for backward compat(TCA_OLD_COMPAT) */
-	__u32			order;
-	struct list_head	list;
-	struct tcf_hashinfo	*hinfo;
-};
-
 #ifdef CONFIG_NET_CLS_ACT
 
 #define ACT_P_CREATED 1
@@ -106,17 +110,18 @@ struct tc_action_ops {
 	struct list_head head;
 	char    kind[IFNAMSIZ];
 	__u32   type; /* TBD to match kind */
+	size_t	size;
 	struct module		*owner;
 	int     (*act)(struct sk_buff *, const struct tc_action *,
 		       struct tcf_result *);
 	int     (*dump)(struct sk_buff *, struct tc_action *, int, int);
 	void	(*cleanup)(struct tc_action *, int bind);
-	int     (*lookup)(struct net *, struct tc_action *, u32);
+	int     (*lookup)(struct net *, struct tc_action **, u32);
 	int     (*init)(struct net *net, struct nlattr *nla,
-			struct nlattr *est, struct tc_action *act, int ovr,
+			struct nlattr *est, struct tc_action **act, int ovr,
 			int bind);
 	int     (*walk)(struct net *, struct sk_buff *,
-			struct netlink_callback *, int, struct tc_action *);
+			struct netlink_callback *, int, const struct tc_action_ops *);
 	void	(*stats_update)(struct tc_action *, u64, u32, u64);
 };
 
@@ -152,13 +157,14 @@ static inline void tc_action_net_exit(struct tc_action_net *tn)
 
 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
 		       struct netlink_callback *cb, int type,
-		       struct tc_action *a);
-int tcf_hash_search(struct tc_action_net *tn, struct tc_action *a, u32 index);
+		       const struct tc_action_ops *ops);
+int tcf_hash_search(struct tc_action_net *tn, struct tc_action **a, u32 index);
 u32 tcf_hash_new_index(struct tc_action_net *tn);
-bool tcf_hash_check(struct tc_action_net *tn, u32 index, struct tc_action *a,
+bool tcf_hash_check(struct tc_action_net *tn, u32 index, struct tc_action **a,
 		    int bind);
 int tcf_hash_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
-		    struct tc_action *a, int size, int bind, bool cpustats);
+		    struct tc_action **a, const struct tc_action_ops *ops, int bind,
+		    bool cpustats);
 void tcf_hash_cleanup(struct tc_action *a, struct nlattr *est);
 void tcf_hash_insert(struct tc_action_net *tn, struct tc_action *a);
 

include/net/tc_act/tc_bpf.h

@@ -23,7 +23,6 @@ struct tcf_bpf {
 	struct sock_filter	*bpf_ops;
 	const char		*bpf_name;
 };
-#define to_bpf(a) \
-	container_of(a->priv, struct tcf_bpf, common)
+#define to_bpf(a) ((struct tcf_bpf *)a)
 
 #endif /* __NET_TC_BPF_H */

include/net/tc_act/tc_connmark.h

@@ -9,7 +9,6 @@ struct tcf_connmark_info {
 	u16 zone;
 };
 
-#define to_connmark(a) \
-	container_of(a->priv, struct tcf_connmark_info, common)
+#define to_connmark(a) ((struct tcf_connmark_info *)a)
 
 #endif /* __NET_TC_CONNMARK_H */

include/net/tc_act/tc_csum.h

@@ -9,7 +9,6 @@ struct tcf_csum {
 
 	u32 update_flags;
 };
-#define to_tcf_csum(a) \
-	container_of(a->priv,struct tcf_csum,common)
+#define to_tcf_csum(a) ((struct tcf_csum *)a)
 
 #endif /* __NET_TC_CSUM_H */

include/net/tc_act/tc_defact.h

@@ -8,7 +8,6 @@ struct tcf_defact {
 	u32		tcfd_datalen;
 	void		*tcfd_defdata;
 };
-#define to_defact(a) \
-	container_of(a->priv, struct tcf_defact, common)
+#define to_defact(a) ((struct tcf_defact *)a)
 
 #endif /* __NET_TC_DEF_H */

include/net/tc_act/tc_gact.h

@@ -13,8 +13,7 @@ struct tcf_gact {
 	atomic_t		packets;
 #endif
 };
-#define to_gact(a) \
-	container_of(a->priv, struct tcf_gact, common)
+#define to_gact(a) ((struct tcf_gact *)a)
 
 static inline bool is_tcf_gact_shot(const struct tc_action *a)
 {
@@ -24,7 +23,7 @@ static inline bool is_tcf_gact_shot(const struct tc_action *a)
 	if (a->ops && a->ops->type != TCA_ACT_GACT)
 		return false;
 
-	gact = a->priv;
+	gact = to_gact(a);
 	if (gact->tcf_action == TC_ACT_SHOT)
 		return true;
 

include/net/tc_act/tc_ife.h

@@ -16,8 +16,7 @@ struct tcf_ife_info {
 	/* list of metaids allowed */
 	struct list_head metalist;
 };
-#define to_ife(a) \
-	container_of(a->priv, struct tcf_ife_info, common)
+#define to_ife(a) ((struct tcf_ife_info *)a)
 
 struct tcf_meta_info {
 	const struct tcf_meta_ops *ops;

include/net/tc_act/tc_ipt.h

@@ -11,7 +11,6 @@ struct tcf_ipt {
 	char			*tcfi_tname;
 	struct xt_entry_target	*tcfi_t;
 };
-#define to_ipt(a) \
-	container_of(a->priv, struct tcf_ipt, common)
+#define to_ipt(a) ((struct tcf_ipt *)a)
 
 #endif /* __NET_TC_IPT_H */

include/net/tc_act/tc_mirred.h

@@ -12,8 +12,7 @@ struct tcf_mirred {
 	struct net_device __rcu	*tcfm_dev;
 	struct list_head	tcfm_list;
 };
-#define to_mirred(a) \
-	container_of(a->priv, struct tcf_mirred, common)
+#define to_mirred(a) ((struct tcf_mirred *)a)
 
 static inline bool is_tcf_mirred_redirect(const struct tc_action *a)
 {

include/net/tc_act/tc_nat.h

@@ -13,9 +13,6 @@ struct tcf_nat {
 	u32 flags;
 };
 
-static inline struct tcf_nat *to_tcf_nat(struct tc_action *a)
-{
-	return container_of(a->priv, struct tcf_nat, common);
-}
+#define to_tcf_nat(a) ((struct tcf_nat *)a)
 
 #endif /* __NET_TC_NAT_H */