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/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef _SOCK_API_EXTRA_H
#define _SOCK_API_EXTRA_H
#include <net/sock_api.h>
/* OOB backlog add */
static inline void __sk_add_backlog(struct sock *sk, struct sk_buff *skb)
{
/* dont let skb dst not refcounted, we are going to leave rcu lock */
skb_dst_force(skb);
if (!sk->sk_backlog.tail)
WRITE_ONCE(sk->sk_backlog.head, skb);
else
sk->sk_backlog.tail->next = skb;
WRITE_ONCE(sk->sk_backlog.tail, skb);
skb->next = NULL;
}
/*
* Take into account size of receive queue and backlog queue
* Do not take into account this skb truesize,
* to allow even a single big packet to come.
*/
static inline bool sk_rcvqueues_full(const struct sock *sk, unsigned int limit)
{
unsigned int qsize = sk->sk_backlog.len + atomic_read(&sk->sk_rmem_alloc);
return qsize > limit;
}
/* The per-socket spinlock must be held here. */
static inline __must_check int sk_add_backlog(struct sock *sk, struct sk_buff *skb,
unsigned int limit)
{
if (sk_rcvqueues_full(sk, limit))
return -ENOBUFS;
/*
* If the skb was allocated from pfmemalloc reserves, only
* allow SOCK_MEMALLOC sockets to use it as this socket is
* helping free memory
*/
if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC))
return -ENOMEM;
__sk_add_backlog(sk, skb);
sk->sk_backlog.len += skb->truesize;
return 0;
}
int __sk_backlog_rcv(struct sock *sk, struct sk_buff *skb);
INDIRECT_CALLABLE_DECLARE(int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb));
INDIRECT_CALLABLE_DECLARE(int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb));
static inline int sk_backlog_rcv(struct sock *sk, struct sk_buff *skb)
{
if (sk_memalloc_socks() && skb_pfmemalloc(skb))
return __sk_backlog_rcv(sk, skb);
return INDIRECT_CALL_INET(sk->sk_backlog_rcv,
tcp_v6_do_rcv,
tcp_v4_do_rcv,
sk, skb);
}
#endif /* _SOCK_API_EXTRA_H */
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