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

#include <linux/filter.h>
#include <linux/skbuff.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <net/sock.h>

extern spinlock_t reuseport_lock;

struct sock_reuseport {
        struct rcu_head         rcu;

        u16                     max_socks;              /* length of socks */
        u16                     num_socks;              /* elements in socks */
        u16                     num_closed_socks;       /* closed elements in socks */
        u16                     incoming_cpu;
        /* The last synq overflow event timestamp of this
         * reuse->socks[] group.
         */
        unsigned int            synq_overflow_ts;
        /* ID stays the same even after the size of socks[] grows. */
        unsigned int            reuseport_id;
        unsigned int            bind_inany:1;
        unsigned int            has_conns:1;
        struct bpf_prog __rcu   *prog;          /* optional BPF sock selector */
        struct sock             *socks[] __counted_by(max_socks);
};

extern int reuseport_alloc(struct sock *sk, bool bind_inany);
extern int reuseport_add_sock(struct sock *sk, struct sock *sk2,
                              bool bind_inany);
extern void reuseport_detach_sock(struct sock *sk);
void reuseport_stop_listen_sock(struct sock *sk);
extern struct sock *reuseport_select_sock(struct sock *sk,
                                          u32 hash,
                                          struct sk_buff *skb,
                                          int hdr_len);
struct sock *reuseport_migrate_sock(struct sock *sk,
                                    struct sock *migrating_sk,
                                    struct sk_buff *skb);
extern int reuseport_attach_prog(struct sock *sk, struct bpf_prog *prog);
extern int reuseport_detach_prog(struct sock *sk);

static inline bool reuseport_has_conns(struct sock *sk)
{
        struct sock_reuseport *reuse;
        bool ret = false;

        rcu_read_lock();
        reuse = rcu_dereference(sk->sk_reuseport_cb);
        if (reuse && reuse->has_conns)
                ret = true;
        rcu_read_unlock();

        return ret;
}

void reuseport_has_conns_set(struct sock *sk);
void reuseport_update_incoming_cpu(struct sock *sk, int val);

#endif  /* _SOCK_REUSEPORT_H */