/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __NET_ACT_API_H
#define __NET_ACT_API_H

/*
 * Public action API for classifiers/qdiscs
*/

#include <linux/refcount.h>
#include <net/flow_offload.h>
#include <net/sch_generic.h>
#include <net/pkt_sched.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>

struct tcf_idrinfo {
        struct mutex    lock;
        struct idr      action_idr;
        struct net      *net;
};

struct tc_action_ops;

struct tc_action {
        const struct tc_action_ops      *ops;
        __u32                           type; /* for backward compat(TCA_OLD_COMPAT) */
        struct tcf_idrinfo              *idrinfo;

        u32                             tcfa_index;
        refcount_t                      tcfa_refcnt;
        atomic_t                        tcfa_bindcnt;
        int                             tcfa_action;
        struct tcf_t                    tcfa_tm;
        struct gnet_stats_basic_sync    tcfa_bstats;
        struct gnet_stats_basic_sync    tcfa_bstats_hw;

        atomic_t                        tcfa_drops;
        atomic_t                        tcfa_overlimits;

        struct net_rate_estimator __rcu *tcfa_rate_est;
        spinlock_t                      tcfa_lock;
        struct gnet_stats_basic_sync __percpu *cpu_bstats;
        struct gnet_stats_basic_sync __percpu *cpu_bstats_hw;
        struct gnet_stats_queue __percpu *cpu_qstats;
        struct tc_cookie        __rcu *user_cookie;
        struct tcf_chain        __rcu *goto_chain;
        u32                     tcfa_flags;
        u8                      hw_stats;
        u8                      used_hw_stats;
        bool                    used_hw_stats_valid;
        u32                     in_hw_count;
};
#define tcf_index       common.tcfa_index
#define tcf_refcnt      common.tcfa_refcnt
#define tcf_bindcnt     common.tcfa_bindcnt
#define tcf_action      common.tcfa_action
#define tcf_tm          common.tcfa_tm
#define tcf_bstats      common.tcfa_bstats
#define tcf_rate_est    common.tcfa_rate_est
#define tcf_lock        common.tcfa_lock

#define TCA_ACT_HW_STATS_ANY (TCA_ACT_HW_STATS_IMMEDIATE | \
                              TCA_ACT_HW_STATS_DELAYED)

/* Reserve 16 bits for user-space. See TCA_ACT_FLAGS_NO_PERCPU_STATS. */
#define TCA_ACT_FLAGS_USER_BITS 16
#define TCA_ACT_FLAGS_USER_MASK 0xffff
#define TCA_ACT_FLAGS_POLICE    (1U << TCA_ACT_FLAGS_USER_BITS)
#define TCA_ACT_FLAGS_BIND      (1U << (TCA_ACT_FLAGS_USER_BITS + 1))
#define TCA_ACT_FLAGS_REPLACE   (1U << (TCA_ACT_FLAGS_USER_BITS + 2))
#define TCA_ACT_FLAGS_NO_RTNL   (1U << (TCA_ACT_FLAGS_USER_BITS + 3))
#define TCA_ACT_FLAGS_AT_INGRESS        (1U << (TCA_ACT_FLAGS_USER_BITS + 4))
#define TCA_ACT_FLAGS_AT_INGRESS_OR_CLSACT      (1U << (TCA_ACT_FLAGS_USER_BITS + 5))

/* Update lastuse only if needed, to avoid dirtying a cache line.
 * We use a temp variable to avoid fetching jiffies twice.
 */
static inline void tcf_lastuse_update(struct tcf_t *tm)
{
        unsigned long now = jiffies;

        if (READ_ONCE(tm->lastuse) != now)
                WRITE_ONCE(tm->lastuse, now);
        if (unlikely(!READ_ONCE(tm->firstuse)))
                WRITE_ONCE(tm->firstuse, now);
}

static inline void tcf_tm_dump(struct tcf_t *dtm, const struct tcf_t *stm)
{
        unsigned long firstuse, now = jiffies;

        dtm->install = jiffies_to_clock_t(now - READ_ONCE(stm->install));
        dtm->lastuse = jiffies_to_clock_t(now - READ_ONCE(stm->lastuse));

        firstuse = READ_ONCE(stm->firstuse);
        dtm->firstuse = firstuse ?
                jiffies_to_clock_t(now - firstuse) : 0;

        dtm->expires = jiffies_to_clock_t(READ_ONCE(stm->expires));
}

static inline enum flow_action_hw_stats tc_act_hw_stats(u8 hw_stats)
{
        if (WARN_ON_ONCE(hw_stats > TCA_ACT_HW_STATS_ANY))
                return FLOW_ACTION_HW_STATS_DONT_CARE;
        else if (!hw_stats)
                return FLOW_ACTION_HW_STATS_DISABLED;

        return hw_stats;
}

typedef void (*tc_action_priv_destructor)(void *priv);

struct tc_action_ops {
        struct list_head head;
        char    kind[IFNAMSIZ];
        enum tca_id  id; /* identifier should match kind */
        unsigned int    net_id;
        size_t  size;
        struct module           *owner;
        int     (*act)(struct sk_buff *, const struct tc_action *,
                       struct tcf_result *); /* called under RCU BH lock*/
        int     (*dump)(struct sk_buff *, struct tc_action *, int, int);
        void    (*cleanup)(struct tc_action *);
        int     (*lookup)(struct net *net, struct tc_action **a, u32 index);
        int     (*init)(struct net *net, struct nlattr *nla,
                        struct nlattr *est, struct tc_action **act,
                        struct tcf_proto *tp,
                        u32 flags, struct netlink_ext_ack *extack);
        int     (*walk)(struct net *, struct sk_buff *,
                        struct netlink_callback *, int,
                        const struct tc_action_ops *,
                        struct netlink_ext_ack *);
        void    (*stats_update)(struct tc_action *, u64, u64, u64, u64, bool);
        size_t  (*get_fill_size)(const struct tc_action *act);
        struct net_device *(*get_dev)(const struct tc_action *a,
                                      tc_action_priv_destructor *destructor);
        struct psample_group *
        (*get_psample_group)(const struct tc_action *a,
                             tc_action_priv_destructor *destructor);
        int     (*offload_act_setup)(struct tc_action *act, void *entry_data,
                                     u32 *index_inc, bool bind,
                                     struct netlink_ext_ack *extack);
};

#ifdef CONFIG_NET_CLS_ACT

#define ACT_P_BOUND 0
#define ACT_P_CREATED 1
#define ACT_P_DELETED 1

struct tc_action_net {
        struct tcf_idrinfo *idrinfo;
        const struct tc_action_ops *ops;
};

static inline
int tc_action_net_init(struct net *net, struct tc_action_net *tn,
                       const struct tc_action_ops *ops)
{
        int err = 0;

        tn->idrinfo = kmalloc_obj(*tn->idrinfo);
        if (!tn->idrinfo)
                return -ENOMEM;
        tn->ops = ops;
        tn->idrinfo->net = net;
        mutex_init(&tn->idrinfo->lock);
        idr_init(&tn->idrinfo->action_idr);
        return err;
}

void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
                         struct tcf_idrinfo *idrinfo);

static inline void tc_action_net_exit(struct list_head *net_list,
                                      unsigned int id)
{
        struct net *net;

        list_for_each_entry(net, net_list, exit_list) {
                struct tc_action_net *tn = net_generic(net, id);

                tcf_idrinfo_destroy(tn->ops, tn->idrinfo);
                kfree(tn->idrinfo);
        }
}

int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
                       struct netlink_callback *cb, int type,
                       const struct tc_action_ops *ops,
                       struct netlink_ext_ack *extack);
int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index);
int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
                   struct tc_action **a, const struct tc_action_ops *ops,
                   int bind, bool cpustats, u32 flags);
int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index,
                              struct nlattr *est, struct tc_action **a,
                              const struct tc_action_ops *ops, int bind,
                              u32 flags);
void tcf_idr_insert_many(struct tc_action *actions[], int init_res[]);
void tcf_idr_cleanup(struct tc_action_net *tn, u32 index);
int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
                        struct tc_action **a, int bind);
int tcf_idr_release(struct tc_action *a, bool bind);

int tcf_register_action(struct tc_action_ops *a, struct pernet_operations *ops);
int tcf_unregister_action(struct tc_action_ops *a,
                          struct pernet_operations *ops);
#define NET_ACT_ALIAS_PREFIX "net-act-"
#define MODULE_ALIAS_NET_ACT(kind)      MODULE_ALIAS(NET_ACT_ALIAS_PREFIX kind)
int tcf_action_destroy(struct tc_action *actions[], int bind);
int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
                    int nr_actions, struct tcf_result *res);
int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
                    struct nlattr *est,
                    struct tc_action *actions[], int init_res[], size_t *attr_size,
                    u32 flags, u32 fl_flags, struct netlink_ext_ack *extack);
struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, u32 flags,
                                         struct netlink_ext_ack *extack);
struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
                                    struct nlattr *nla, struct nlattr *est,
                                    struct tc_action_ops *a_o, int *init_res,
                                    u32 flags, struct netlink_ext_ack *extack);
int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[], int bind,
                    int ref, bool terse);
int tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int, int);

static inline void tcf_action_update_bstats(struct tc_action *a,
                                            struct sk_buff *skb)
{
        if (likely(a->cpu_bstats)) {
                bstats_update(this_cpu_ptr(a->cpu_bstats), skb);
                return;
        }
        spin_lock(&a->tcfa_lock);
        bstats_update(&a->tcfa_bstats, skb);
        spin_unlock(&a->tcfa_lock);
}

static inline void tcf_action_inc_drop_qstats(struct tc_action *a)
{
        if (likely(a->cpu_qstats)) {
                qstats_drop_inc(this_cpu_ptr(a->cpu_qstats));
                return;
        }
        atomic_inc(&a->tcfa_drops);
}

static inline void tcf_action_inc_overlimit_qstats(struct tc_action *a)
{
        if (likely(a->cpu_qstats)) {
                qstats_overlimit_inc(this_cpu_ptr(a->cpu_qstats));
                return;
        }
        atomic_inc(&a->tcfa_overlimits);
}

void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
                             u64 drops, bool hw);
int tcf_action_copy_stats(struct sk_buff *, struct tc_action *, int);

int tcf_action_update_hw_stats(struct tc_action *action);
int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
                            void *cb_priv, bool add);
int tcf_action_check_ctrlact(int action, struct tcf_proto *tp,
                             struct tcf_chain **handle,
                             struct netlink_ext_ack *newchain);
struct tcf_chain *tcf_action_set_ctrlact(struct tc_action *a, int action,
                                         struct tcf_chain *newchain);

#ifdef CONFIG_INET
DECLARE_STATIC_KEY_FALSE(tcf_frag_xmit_count);
#endif

int tcf_dev_queue_xmit(struct sk_buff *skb, int (*xmit)(struct sk_buff *skb));

#else /* !CONFIG_NET_CLS_ACT */

static inline int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
                                          void *cb_priv, bool add) {
        return 0;
}

#endif /* CONFIG_NET_CLS_ACT */

static inline void tcf_action_stats_update(struct tc_action *a, u64 bytes,
                                           u64 packets, u64 drops,
                                           u64 lastuse, bool hw)
{
#ifdef CONFIG_NET_CLS_ACT
        if (!a->ops->stats_update)
                return;

        a->ops->stats_update(a, bytes, packets, drops, lastuse, hw);
#endif
}


#endif