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15#ifndef _REQUEST_SOCK_H
16#define _REQUEST_SOCK_H
17
18#include <linux/slab.h>
19#include <linux/spinlock.h>
20#include <linux/types.h>
21#include <linux/bug.h>
22
23#include <net/sock.h>
24
25struct request_sock;
26struct sk_buff;
27struct dst_entry;
28struct proto;
29
30
31
32struct request_values {
33};
34
35struct request_sock_ops {
36 int family;
37 int obj_size;
38 struct kmem_cache *slab;
39 char *slab_name;
40 int (*rtx_syn_ack)(struct sock *sk,
41 struct request_sock *req,
42 struct request_values *rvp);
43 void (*send_ack)(struct sock *sk, struct sk_buff *skb,
44 struct request_sock *req);
45 void (*send_reset)(struct sock *sk,
46 struct sk_buff *skb);
47 void (*destructor)(struct request_sock *req);
48 void (*syn_ack_timeout)(struct sock *sk,
49 struct request_sock *req);
50};
51
52
53
54struct request_sock {
55 struct request_sock *dl_next;
56 u16 mss;
57 u8 retrans;
58 u8 cookie_ts;
59
60 u32 window_clamp;
61 u32 rcv_wnd;
62 u32 ts_recent;
63 unsigned long expires;
64 const struct request_sock_ops *rsk_ops;
65 struct sock *sk;
66 u32 secid;
67 u32 peer_secid;
68};
69
70static inline struct request_sock *reqsk_alloc(const struct request_sock_ops *ops)
71{
72 struct request_sock *req = kmem_cache_alloc(ops->slab, GFP_ATOMIC);
73
74 if (req != NULL)
75 req->rsk_ops = ops;
76
77 return req;
78}
79
80static inline void __reqsk_free(struct request_sock *req)
81{
82 kmem_cache_free(req->rsk_ops->slab, req);
83}
84
85static inline void reqsk_free(struct request_sock *req)
86{
87 req->rsk_ops->destructor(req);
88 __reqsk_free(req);
89}
90
91extern int sysctl_max_syn_backlog;
92
93
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96
97struct listen_sock {
98 u8 max_qlen_log;
99
100 int qlen;
101 int qlen_young;
102 int clock_hand;
103 u32 hash_rnd;
104 u32 nr_table_entries;
105 struct request_sock *syn_table[0];
106};
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123
124struct request_sock_queue {
125 struct request_sock *rskq_accept_head;
126 struct request_sock *rskq_accept_tail;
127 rwlock_t syn_wait_lock;
128 u8 rskq_defer_accept;
129
130 struct listen_sock *listen_opt;
131};
132
133extern int reqsk_queue_alloc(struct request_sock_queue *queue,
134 unsigned int nr_table_entries);
135
136extern void __reqsk_queue_destroy(struct request_sock_queue *queue);
137extern void reqsk_queue_destroy(struct request_sock_queue *queue);
138
139static inline struct request_sock *
140 reqsk_queue_yank_acceptq(struct request_sock_queue *queue)
141{
142 struct request_sock *req = queue->rskq_accept_head;
143
144 queue->rskq_accept_head = NULL;
145 return req;
146}
147
148static inline int reqsk_queue_empty(struct request_sock_queue *queue)
149{
150 return queue->rskq_accept_head == NULL;
151}
152
153static inline void reqsk_queue_unlink(struct request_sock_queue *queue,
154 struct request_sock *req,
155 struct request_sock **prev_req)
156{
157 write_lock(&queue->syn_wait_lock);
158 *prev_req = req->dl_next;
159 write_unlock(&queue->syn_wait_lock);
160}
161
162static inline void reqsk_queue_add(struct request_sock_queue *queue,
163 struct request_sock *req,
164 struct sock *parent,
165 struct sock *child)
166{
167 req->sk = child;
168 sk_acceptq_added(parent);
169
170 if (queue->rskq_accept_head == NULL)
171 queue->rskq_accept_head = req;
172 else
173 queue->rskq_accept_tail->dl_next = req;
174
175 queue->rskq_accept_tail = req;
176 req->dl_next = NULL;
177}
178
179static inline struct request_sock *reqsk_queue_remove(struct request_sock_queue *queue)
180{
181 struct request_sock *req = queue->rskq_accept_head;
182
183 WARN_ON(req == NULL);
184
185 queue->rskq_accept_head = req->dl_next;
186 if (queue->rskq_accept_head == NULL)
187 queue->rskq_accept_tail = NULL;
188
189 return req;
190}
191
192static inline struct sock *reqsk_queue_get_child(struct request_sock_queue *queue,
193 struct sock *parent)
194{
195 struct request_sock *req = reqsk_queue_remove(queue);
196 struct sock *child = req->sk;
197
198 WARN_ON(child == NULL);
199
200 sk_acceptq_removed(parent);
201 __reqsk_free(req);
202 return child;
203}
204
205static inline int reqsk_queue_removed(struct request_sock_queue *queue,
206 struct request_sock *req)
207{
208 struct listen_sock *lopt = queue->listen_opt;
209
210 if (req->retrans == 0)
211 --lopt->qlen_young;
212
213 return --lopt->qlen;
214}
215
216static inline int reqsk_queue_added(struct request_sock_queue *queue)
217{
218 struct listen_sock *lopt = queue->listen_opt;
219 const int prev_qlen = lopt->qlen;
220
221 lopt->qlen_young++;
222 lopt->qlen++;
223 return prev_qlen;
224}
225
226static inline int reqsk_queue_len(const struct request_sock_queue *queue)
227{
228 return queue->listen_opt != NULL ? queue->listen_opt->qlen : 0;
229}
230
231static inline int reqsk_queue_len_young(const struct request_sock_queue *queue)
232{
233 return queue->listen_opt->qlen_young;
234}
235
236static inline int reqsk_queue_is_full(const struct request_sock_queue *queue)
237{
238 return queue->listen_opt->qlen >> queue->listen_opt->max_qlen_log;
239}
240
241static inline void reqsk_queue_hash_req(struct request_sock_queue *queue,
242 u32 hash, struct request_sock *req,
243 unsigned long timeout)
244{
245 struct listen_sock *lopt = queue->listen_opt;
246
247 req->expires = jiffies + timeout;
248 req->retrans = 0;
249 req->sk = NULL;
250 req->dl_next = lopt->syn_table[hash];
251
252 write_lock(&queue->syn_wait_lock);
253 lopt->syn_table[hash] = req;
254 write_unlock(&queue->syn_wait_lock);
255}
256
257#endif
258