xref: /linux/include/net/inet_frag.h (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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 	u16			max_size;
34 };
35 
36 #define INETFRAGS_HASHSZ		64
37 
38 struct inet_frags {
39 	struct hlist_head	hash[INETFRAGS_HASHSZ];
40 	rwlock_t		lock;
41 	u32			rnd;
42 	int			qsize;
43 	int			secret_interval;
44 	struct timer_list	secret_timer;
45 
46 	unsigned int		(*hashfn)(struct inet_frag_queue *);
47 	void			(*constructor)(struct inet_frag_queue *q,
48 						void *arg);
49 	void			(*destructor)(struct inet_frag_queue *);
50 	void			(*skb_free)(struct sk_buff *);
51 	bool			(*match)(struct inet_frag_queue *q, void *arg);
52 	void			(*frag_expire)(unsigned long data);
53 };
54 
55 void inet_frags_init(struct inet_frags *);
56 void inet_frags_fini(struct inet_frags *);
57 
58 void inet_frags_init_net(struct netns_frags *nf);
59 void inet_frags_exit_net(struct netns_frags *nf, struct inet_frags *f);
60 
61 void inet_frag_kill(struct inet_frag_queue *q, struct inet_frags *f);
62 void inet_frag_destroy(struct inet_frag_queue *q,
63 				struct inet_frags *f, int *work);
64 int inet_frag_evictor(struct netns_frags *nf, struct inet_frags *f, bool force);
65 struct inet_frag_queue *inet_frag_find(struct netns_frags *nf,
66 		struct inet_frags *f, void *key, unsigned int hash)
67 	__releases(&f->lock);
68 
69 static inline void inet_frag_put(struct inet_frag_queue *q, struct inet_frags *f)
70 {
71 	if (atomic_dec_and_test(&q->refcnt))
72 		inet_frag_destroy(q, f, NULL);
73 }
74 
75 #endif
76