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1#ifndef __NET_FRAG_H__
2#define __NET_FRAG_H__
3
4struct 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
15struct 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
36struct 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 int (*match)(struct inet_frag_queue *q,
50 void *arg);
51 void (*frag_expire)(unsigned long data);
52};
53
54void inet_frags_init(struct inet_frags *);
55void inet_frags_fini(struct inet_frags *);
56
57void inet_frags_init_net(struct netns_frags *nf);
58void inet_frags_exit_net(struct netns_frags *nf, struct inet_frags *f);
59
60void inet_frag_kill(struct inet_frag_queue *q, struct inet_frags *f);
61void inet_frag_destroy(struct inet_frag_queue *q,
62 struct inet_frags *f, int *work);
63int inet_frag_evictor(struct netns_frags *nf, struct inet_frags *f);
64struct inet_frag_queue *inet_frag_find(struct netns_frags *nf,
65 struct inet_frags *f, void *key, unsigned int hash)
66 __releases(&f->lock);
67
68static inline void inet_frag_put(struct inet_frag_queue *q, struct inet_frags *f)
69{
70 if (atomic_dec_and_test(&q->refcnt))
71 inet_frag_destroy(q, f, NULL);
72}
73
74#endif
1#ifndef __NET_FRAG_H__
2#define __NET_FRAG_H__
3
4#include <linux/percpu_counter.h>
5
6struct netns_frags {
7 int nqueues;
8 struct list_head lru_list;
9 spinlock_t lru_lock;
10
11 /* The percpu_counter "mem" need to be cacheline aligned.
12 * mem.count must not share cacheline with other writers
13 */
14 struct percpu_counter mem ____cacheline_aligned_in_smp;
15
16 /* sysctls */
17 int timeout;
18 int high_thresh;
19 int low_thresh;
20};
21
22struct inet_frag_queue {
23 spinlock_t lock;
24 struct timer_list timer; /* when will this queue expire? */
25 struct list_head lru_list; /* lru list member */
26 struct hlist_node list;
27 atomic_t refcnt;
28 struct sk_buff *fragments; /* list of received fragments */
29 struct sk_buff *fragments_tail;
30 ktime_t stamp;
31 int len; /* total length of orig datagram */
32 int meat;
33 __u8 last_in; /* first/last segment arrived? */
34
35#define INET_FRAG_COMPLETE 4
36#define INET_FRAG_FIRST_IN 2
37#define INET_FRAG_LAST_IN 1
38
39 u16 max_size;
40
41 struct netns_frags *net;
42};
43
44#define INETFRAGS_HASHSZ 1024
45
46/* averaged:
47 * max_depth = default ipfrag_high_thresh / INETFRAGS_HASHSZ /
48 * rounded up (SKB_TRUELEN(0) + sizeof(struct ipq or
49 * struct frag_queue))
50 */
51#define INETFRAGS_MAXDEPTH 128
52
53struct inet_frag_bucket {
54 struct hlist_head chain;
55 spinlock_t chain_lock;
56};
57
58struct inet_frags {
59 struct inet_frag_bucket hash[INETFRAGS_HASHSZ];
60 /* This rwlock is a global lock (seperate per IPv4, IPv6 and
61 * netfilter). Important to keep this on a seperate cacheline.
62 * Its primarily a rebuild protection rwlock.
63 */
64 rwlock_t lock ____cacheline_aligned_in_smp;
65 int secret_interval;
66 struct timer_list secret_timer;
67
68 /* The first call to hashfn is responsible to initialize
69 * rnd. This is best done with net_get_random_once.
70 */
71 u32 rnd;
72 int qsize;
73
74 unsigned int (*hashfn)(struct inet_frag_queue *);
75 bool (*match)(struct inet_frag_queue *q, void *arg);
76 void (*constructor)(struct inet_frag_queue *q,
77 void *arg);
78 void (*destructor)(struct inet_frag_queue *);
79 void (*skb_free)(struct sk_buff *);
80 void (*frag_expire)(unsigned long data);
81};
82
83void inet_frags_init(struct inet_frags *);
84void inet_frags_fini(struct inet_frags *);
85
86void inet_frags_init_net(struct netns_frags *nf);
87void inet_frags_exit_net(struct netns_frags *nf, struct inet_frags *f);
88
89void inet_frag_kill(struct inet_frag_queue *q, struct inet_frags *f);
90void inet_frag_destroy(struct inet_frag_queue *q,
91 struct inet_frags *f, int *work);
92int inet_frag_evictor(struct netns_frags *nf, struct inet_frags *f, bool force);
93struct inet_frag_queue *inet_frag_find(struct netns_frags *nf,
94 struct inet_frags *f, void *key, unsigned int hash)
95 __releases(&f->lock);
96void inet_frag_maybe_warn_overflow(struct inet_frag_queue *q,
97 const char *prefix);
98
99static inline void inet_frag_put(struct inet_frag_queue *q, struct inet_frags *f)
100{
101 if (atomic_dec_and_test(&q->refcnt))
102 inet_frag_destroy(q, f, NULL);
103}
104
105/* Memory Tracking Functions. */
106
107/* The default percpu_counter batch size is not big enough to scale to
108 * fragmentation mem acct sizes.
109 * The mem size of a 64K fragment is approx:
110 * (44 fragments * 2944 truesize) + frag_queue struct(200) = 129736 bytes
111 */
112static unsigned int frag_percpu_counter_batch = 130000;
113
114static inline int frag_mem_limit(struct netns_frags *nf)
115{
116 return percpu_counter_read(&nf->mem);
117}
118
119static inline void sub_frag_mem_limit(struct inet_frag_queue *q, int i)
120{
121 __percpu_counter_add(&q->net->mem, -i, frag_percpu_counter_batch);
122}
123
124static inline void add_frag_mem_limit(struct inet_frag_queue *q, int i)
125{
126 __percpu_counter_add(&q->net->mem, i, frag_percpu_counter_batch);
127}
128
129static inline void init_frag_mem_limit(struct netns_frags *nf)
130{
131 percpu_counter_init(&nf->mem, 0);
132}
133
134static inline int sum_frag_mem_limit(struct netns_frags *nf)
135{
136 int res;
137
138 local_bh_disable();
139 res = percpu_counter_sum_positive(&nf->mem);
140 local_bh_enable();
141
142 return res;
143}
144
145static inline void inet_frag_lru_move(struct inet_frag_queue *q)
146{
147 spin_lock(&q->net->lru_lock);
148 if (!list_empty(&q->lru_list))
149 list_move_tail(&q->lru_list, &q->net->lru_list);
150 spin_unlock(&q->net->lru_lock);
151}
152
153static inline void inet_frag_lru_del(struct inet_frag_queue *q)
154{
155 spin_lock(&q->net->lru_lock);
156 list_del_init(&q->lru_list);
157 q->net->nqueues--;
158 spin_unlock(&q->net->lru_lock);
159}
160
161static inline void inet_frag_lru_add(struct netns_frags *nf,
162 struct inet_frag_queue *q)
163{
164 spin_lock(&nf->lru_lock);
165 list_add_tail(&q->lru_list, &nf->lru_list);
166 q->net->nqueues++;
167 spin_unlock(&nf->lru_lock);
168}
169
170/* RFC 3168 support :
171 * We want to check ECN values of all fragments, do detect invalid combinations.
172 * In ipq->ecn, we store the OR value of each ip4_frag_ecn() fragment value.
173 */
174#define IPFRAG_ECN_NOT_ECT 0x01 /* one frag had ECN_NOT_ECT */
175#define IPFRAG_ECN_ECT_1 0x02 /* one frag had ECN_ECT_1 */
176#define IPFRAG_ECN_ECT_0 0x04 /* one frag had ECN_ECT_0 */
177#define IPFRAG_ECN_CE 0x08 /* one frag had ECN_CE */
178
179extern const u8 ip_frag_ecn_table[16];
180
181#endif