Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 1 | /* |
| 2 | * NET Generic infrastructure for Network protocols. |
| 3 | * |
| 4 | * Definitions for request_sock |
| 5 | * |
| 6 | * Authors: Arnaldo Carvalho de Melo <acme@conectiva.com.br> |
| 7 | * |
| 8 | * From code originally in include/net/tcp.h |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU General Public License |
| 12 | * as published by the Free Software Foundation; either version |
| 13 | * 2 of the License, or (at your option) any later version. |
| 14 | */ |
| 15 | #ifndef _REQUEST_SOCK_H |
| 16 | #define _REQUEST_SOCK_H |
| 17 | |
| 18 | #include <linux/slab.h> |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 19 | #include <linux/spinlock.h> |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 20 | #include <linux/types.h> |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 21 | #include <linux/bug.h> |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 22 | |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 23 | #include <net/sock.h> |
| 24 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 25 | struct request_sock; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 26 | struct sk_buff; |
| 27 | struct dst_entry; |
| 28 | struct proto; |
| 29 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 30 | struct request_sock_ops { |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 31 | int family; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 32 | int obj_size; |
Christoph Lameter | e18b890 | 2006-12-06 20:33:20 -0800 | [diff] [blame] | 33 | struct kmem_cache *slab; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 34 | int (*rtx_syn_ack)(struct sock *sk, |
Denis V. Lunev | fd80eb9 | 2008-02-29 11:43:03 -0800 | [diff] [blame] | 35 | struct request_sock *req); |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 36 | void (*send_ack)(struct sk_buff *skb, |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 37 | struct request_sock *req); |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 38 | void (*send_reset)(struct sock *sk, |
| 39 | struct sk_buff *skb); |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 40 | void (*destructor)(struct request_sock *req); |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 41 | }; |
| 42 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 43 | /* struct request_sock - mini sock to represent a connection request |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 44 | */ |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 45 | struct request_sock { |
| 46 | struct request_sock *dl_next; /* Must be first member! */ |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 47 | u16 mss; |
| 48 | u8 retrans; |
Florian Westphal | 4dfc281 | 2008-04-10 03:12:40 -0700 | [diff] [blame] | 49 | u8 cookie_ts; /* syncookie: encode tcpopts in timestamp */ |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 50 | /* The following two fields can be easily recomputed I think -AK */ |
| 51 | u32 window_clamp; /* window clamp at creation time */ |
| 52 | u32 rcv_wnd; /* rcv_wnd offered first time */ |
| 53 | u32 ts_recent; |
| 54 | unsigned long expires; |
Eric Dumazet | 72a3eff | 2006-11-16 02:30:37 -0800 | [diff] [blame] | 55 | const struct request_sock_ops *rsk_ops; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 56 | struct sock *sk; |
Venkat Yekkirala | 4237c75 | 2006-07-24 23:32:50 -0700 | [diff] [blame] | 57 | u32 secid; |
Venkat Yekkirala | 6b87769 | 2006-11-08 17:04:09 -0600 | [diff] [blame] | 58 | u32 peer_secid; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 59 | }; |
| 60 | |
Eric Dumazet | 72a3eff | 2006-11-16 02:30:37 -0800 | [diff] [blame] | 61 | static inline struct request_sock *reqsk_alloc(const struct request_sock_ops *ops) |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 62 | { |
Christoph Lameter | 54e6ecb | 2006-12-06 20:33:16 -0800 | [diff] [blame] | 63 | struct request_sock *req = kmem_cache_alloc(ops->slab, GFP_ATOMIC); |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 64 | |
| 65 | if (req != NULL) |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 66 | req->rsk_ops = ops; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 67 | |
| 68 | return req; |
| 69 | } |
| 70 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 71 | static inline void __reqsk_free(struct request_sock *req) |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 72 | { |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 73 | kmem_cache_free(req->rsk_ops->slab, req); |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 74 | } |
| 75 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 76 | static inline void reqsk_free(struct request_sock *req) |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 77 | { |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 78 | req->rsk_ops->destructor(req); |
| 79 | __reqsk_free(req); |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 80 | } |
| 81 | |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 82 | extern int sysctl_max_syn_backlog; |
| 83 | |
Arnaldo Carvalho de Melo | 2ad69c5 | 2005-06-18 22:48:55 -0700 | [diff] [blame] | 84 | /** struct listen_sock - listen state |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 85 | * |
| 86 | * @max_qlen_log - log_2 of maximal queued SYNs/REQUESTs |
| 87 | */ |
Arnaldo Carvalho de Melo | 2ad69c5 | 2005-06-18 22:48:55 -0700 | [diff] [blame] | 88 | struct listen_sock { |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 89 | u8 max_qlen_log; |
| 90 | /* 3 bytes hole, try to use */ |
| 91 | int qlen; |
| 92 | int qlen_young; |
| 93 | int clock_hand; |
| 94 | u32 hash_rnd; |
Arnaldo Carvalho de Melo | 83e3609 | 2005-08-09 19:33:31 -0700 | [diff] [blame] | 95 | u32 nr_table_entries; |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 96 | struct request_sock *syn_table[0]; |
| 97 | }; |
| 98 | |
| 99 | /** struct request_sock_queue - queue of request_socks |
| 100 | * |
| 101 | * @rskq_accept_head - FIFO head of established children |
| 102 | * @rskq_accept_tail - FIFO tail of established children |
Arnaldo Carvalho de Melo | 295f732 | 2005-08-09 20:11:56 -0700 | [diff] [blame] | 103 | * @rskq_defer_accept - User waits for some data after accept() |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 104 | * @syn_wait_lock - serializer |
| 105 | * |
| 106 | * %syn_wait_lock is necessary only to avoid proc interface having to grab the main |
| 107 | * lock sock while browsing the listening hash (otherwise it's deadlock prone). |
| 108 | * |
| 109 | * This lock is acquired in read mode only from listening_get_next() seq_file |
| 110 | * op and it's acquired in write mode _only_ from code that is actively |
| 111 | * changing rskq_accept_head. All readers that are holding the master sock lock |
| 112 | * don't need to grab this lock in read mode too as rskq_accept_head. writes |
| 113 | * are always protected from the main sock lock. |
| 114 | */ |
| 115 | struct request_sock_queue { |
| 116 | struct request_sock *rskq_accept_head; |
| 117 | struct request_sock *rskq_accept_tail; |
| 118 | rwlock_t syn_wait_lock; |
David S. Miller | ec0a196 | 2008-06-12 16:31:35 -0700 | [diff] [blame] | 119 | u8 rskq_defer_accept; |
| 120 | /* 3 bytes hole, try to pack */ |
Arnaldo Carvalho de Melo | 2ad69c5 | 2005-06-18 22:48:55 -0700 | [diff] [blame] | 121 | struct listen_sock *listen_opt; |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 122 | }; |
| 123 | |
| 124 | extern int reqsk_queue_alloc(struct request_sock_queue *queue, |
Eric Dumazet | 72a3eff | 2006-11-16 02:30:37 -0800 | [diff] [blame] | 125 | unsigned int nr_table_entries); |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 126 | |
Pavel Emelyanov | dab6ba3 | 2007-11-15 02:57:06 -0800 | [diff] [blame] | 127 | extern void __reqsk_queue_destroy(struct request_sock_queue *queue); |
Arnaldo Carvalho de Melo | 83e3609 | 2005-08-09 19:33:31 -0700 | [diff] [blame] | 128 | extern void reqsk_queue_destroy(struct request_sock_queue *queue); |
| 129 | |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 130 | static inline struct request_sock * |
| 131 | reqsk_queue_yank_acceptq(struct request_sock_queue *queue) |
| 132 | { |
| 133 | struct request_sock *req = queue->rskq_accept_head; |
| 134 | |
Norbert Kiesel | 3eb4801 | 2006-03-26 17:39:55 -0800 | [diff] [blame] | 135 | queue->rskq_accept_head = NULL; |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 136 | return req; |
| 137 | } |
| 138 | |
| 139 | static inline int reqsk_queue_empty(struct request_sock_queue *queue) |
| 140 | { |
| 141 | return queue->rskq_accept_head == NULL; |
| 142 | } |
| 143 | |
| 144 | static inline void reqsk_queue_unlink(struct request_sock_queue *queue, |
| 145 | struct request_sock *req, |
| 146 | struct request_sock **prev_req) |
| 147 | { |
| 148 | write_lock(&queue->syn_wait_lock); |
| 149 | *prev_req = req->dl_next; |
| 150 | write_unlock(&queue->syn_wait_lock); |
| 151 | } |
| 152 | |
| 153 | static inline void reqsk_queue_add(struct request_sock_queue *queue, |
| 154 | struct request_sock *req, |
| 155 | struct sock *parent, |
| 156 | struct sock *child) |
| 157 | { |
| 158 | req->sk = child; |
| 159 | sk_acceptq_added(parent); |
| 160 | |
| 161 | if (queue->rskq_accept_head == NULL) |
| 162 | queue->rskq_accept_head = req; |
| 163 | else |
| 164 | queue->rskq_accept_tail->dl_next = req; |
| 165 | |
| 166 | queue->rskq_accept_tail = req; |
| 167 | req->dl_next = NULL; |
| 168 | } |
| 169 | |
| 170 | static inline struct request_sock *reqsk_queue_remove(struct request_sock_queue *queue) |
| 171 | { |
| 172 | struct request_sock *req = queue->rskq_accept_head; |
| 173 | |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 174 | WARN_ON(req == NULL); |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 175 | |
| 176 | queue->rskq_accept_head = req->dl_next; |
| 177 | if (queue->rskq_accept_head == NULL) |
| 178 | queue->rskq_accept_tail = NULL; |
| 179 | |
| 180 | return req; |
| 181 | } |
| 182 | |
| 183 | static inline struct sock *reqsk_queue_get_child(struct request_sock_queue *queue, |
| 184 | struct sock *parent) |
| 185 | { |
| 186 | struct request_sock *req = reqsk_queue_remove(queue); |
| 187 | struct sock *child = req->sk; |
| 188 | |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 189 | WARN_ON(child == NULL); |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 190 | |
| 191 | sk_acceptq_removed(parent); |
| 192 | __reqsk_free(req); |
| 193 | return child; |
| 194 | } |
| 195 | |
| 196 | static inline int reqsk_queue_removed(struct request_sock_queue *queue, |
| 197 | struct request_sock *req) |
| 198 | { |
Arnaldo Carvalho de Melo | 2ad69c5 | 2005-06-18 22:48:55 -0700 | [diff] [blame] | 199 | struct listen_sock *lopt = queue->listen_opt; |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 200 | |
| 201 | if (req->retrans == 0) |
| 202 | --lopt->qlen_young; |
| 203 | |
| 204 | return --lopt->qlen; |
| 205 | } |
| 206 | |
| 207 | static inline int reqsk_queue_added(struct request_sock_queue *queue) |
| 208 | { |
Arnaldo Carvalho de Melo | 2ad69c5 | 2005-06-18 22:48:55 -0700 | [diff] [blame] | 209 | struct listen_sock *lopt = queue->listen_opt; |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 210 | const int prev_qlen = lopt->qlen; |
| 211 | |
| 212 | lopt->qlen_young++; |
| 213 | lopt->qlen++; |
| 214 | return prev_qlen; |
| 215 | } |
| 216 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 217 | static inline int reqsk_queue_len(const struct request_sock_queue *queue) |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 218 | { |
| 219 | return queue->listen_opt != NULL ? queue->listen_opt->qlen : 0; |
| 220 | } |
| 221 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 222 | static inline int reqsk_queue_len_young(const struct request_sock_queue *queue) |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 223 | { |
| 224 | return queue->listen_opt->qlen_young; |
| 225 | } |
| 226 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 227 | static inline int reqsk_queue_is_full(const struct request_sock_queue *queue) |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 228 | { |
| 229 | return queue->listen_opt->qlen >> queue->listen_opt->max_qlen_log; |
| 230 | } |
| 231 | |
| 232 | static inline void reqsk_queue_hash_req(struct request_sock_queue *queue, |
| 233 | u32 hash, struct request_sock *req, |
Arnaldo Carvalho de Melo | 8129765 | 2005-12-13 23:15:24 -0800 | [diff] [blame] | 234 | unsigned long timeout) |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 235 | { |
Arnaldo Carvalho de Melo | 2ad69c5 | 2005-06-18 22:48:55 -0700 | [diff] [blame] | 236 | struct listen_sock *lopt = queue->listen_opt; |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 237 | |
| 238 | req->expires = jiffies + timeout; |
| 239 | req->retrans = 0; |
| 240 | req->sk = NULL; |
| 241 | req->dl_next = lopt->syn_table[hash]; |
| 242 | |
| 243 | write_lock(&queue->syn_wait_lock); |
| 244 | lopt->syn_table[hash] = req; |
| 245 | write_unlock(&queue->syn_wait_lock); |
| 246 | } |
| 247 | |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 248 | #endif /* _REQUEST_SOCK_H */ |