xref: /linux/include/net/inet_frag.h (revision 4413e16d9d21673bb5048a2e542f1aaa00015c2e)
1 #ifndef __NET_FRAG_H__
2 #define __NET_FRAG_H__
3 
4 struct netns_frags {
5 	int			nqueues;
6 	atomic_t		mem;
7 	struct list_head	lru_list;
8 
9 	/* sysctls */
10 	int			timeout;
11 	int			high_thresh;
12 	int			low_thresh;
13 };
14 
15 struct inet_frag_queue {
16 	struct hlist_node	list;
17 	struct netns_frags	*net;
18 	struct list_head	lru_list;   /* lru list member */
19 	spinlock_t		lock;
20 	atomic_t		refcnt;
21 	struct timer_list	timer;      /* when will this queue expire? */
22 	struct sk_buff		*fragments; /* list of received fragments */
23 	struct sk_buff		*fragments_tail;
24 	ktime_t			stamp;
25 	int			len;        /* total length of orig datagram */
26 	int			meat;
27 	__u8			last_in;    /* first/last segment arrived? */
28 
29 #define INET_FRAG_COMPLETE	4
30 #define INET_FRAG_FIRST_IN	2
31 #define INET_FRAG_LAST_IN	1
32 };
33 
34 #define INETFRAGS_HASHSZ		64
35 
36 struct inet_frags {
37 	struct hlist_head	hash[INETFRAGS_HASHSZ];
38 	rwlock_t		lock;
39 	u32			rnd;
40 	int			qsize;
41 	int			secret_interval;
42 	struct timer_list	secret_timer;
43 
44 	unsigned int		(*hashfn)(struct inet_frag_queue *);
45 	void			(*constructor)(struct inet_frag_queue *q,
46 						void *arg);
47 	void			(*destructor)(struct inet_frag_queue *);
48 	void			(*skb_free)(struct sk_buff *);
49 	bool			(*match)(struct inet_frag_queue *q, void *arg);
50 	void			(*frag_expire)(unsigned long data);
51 };
52 
53 void inet_frags_init(struct inet_frags *);
54 void inet_frags_fini(struct inet_frags *);
55 
56 void inet_frags_init_net(struct netns_frags *nf);
57 void inet_frags_exit_net(struct netns_frags *nf, struct inet_frags *f);
58 
59 void inet_frag_kill(struct inet_frag_queue *q, struct inet_frags *f);
60 void inet_frag_destroy(struct inet_frag_queue *q,
61 				struct inet_frags *f, int *work);
62 int inet_frag_evictor(struct netns_frags *nf, struct inet_frags *f);
63 struct inet_frag_queue *inet_frag_find(struct netns_frags *nf,
64 		struct inet_frags *f, void *key, unsigned int hash)
65 	__releases(&f->lock);
66 
67 static inline void inet_frag_put(struct inet_frag_queue *q, struct inet_frags *f)
68 {
69 	if (atomic_dec_and_test(&q->refcnt))
70 		inet_frag_destroy(q, f, NULL);
71 }
72 
73 #endif
74