linux/include/net/sock_reuseport.h
Kuniyuki Iwashima 1cd62c2157 tcp: Add reuseport_migrate_sock() to select a new listener.
reuseport_migrate_sock() does the same check done in
reuseport_listen_stop_sock(). If the reuseport group is capable of
migration, reuseport_migrate_sock() selects a new listener by the child
socket hash and increments the listener's sk_refcnt beforehand. Thus, if we
fail in the migration, we have to decrement it later.

We will support migration by eBPF in the later commits.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/bpf/20210612123224.12525-5-kuniyu@amazon.co.jp
2021-06-15 18:01:05 +02:00

64 lines
1.7 KiB
C

/* 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 */
/* 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[]; /* array of sock pointers */
};
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, bool set)
{
struct sock_reuseport *reuse;
bool ret = false;
rcu_read_lock();
reuse = rcu_dereference(sk->sk_reuseport_cb);
if (reuse) {
if (set)
reuse->has_conns = 1;
ret = reuse->has_conns;
}
rcu_read_unlock();
return ret;
}
#endif /* _SOCK_REUSEPORT_H */