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 | |
William Allen Simpson | e6b4d11 | 2009-12-02 18:07:39 +0000 | [diff] [blame] | 30 | /* empty to "strongly type" an otherwise void parameter. |
| 31 | */ |
| 32 | struct request_values { |
| 33 | }; |
| 34 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 35 | struct request_sock_ops { |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 36 | int family; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 37 | int obj_size; |
Christoph Lameter | e18b890 | 2006-12-06 20:33:20 -0800 | [diff] [blame] | 38 | struct kmem_cache *slab; |
Catalin Marinas | 7e56b5d | 2008-11-21 16:45:22 -0800 | [diff] [blame] | 39 | char *slab_name; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 40 | int (*rtx_syn_ack)(struct sock *sk, |
William Allen Simpson | e6b4d11 | 2009-12-02 18:07:39 +0000 | [diff] [blame] | 41 | struct request_sock *req, |
| 42 | struct request_values *rvp); |
Gui Jianfeng | 6edafaa | 2008-08-06 23:50:04 -0700 | [diff] [blame] | 43 | void (*send_ack)(struct sock *sk, struct sk_buff *skb, |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 44 | struct request_sock *req); |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 45 | void (*send_reset)(struct sock *sk, |
| 46 | struct sk_buff *skb); |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 47 | void (*destructor)(struct request_sock *req); |
Octavian Purdila | 72659ec | 2010-01-17 19:09:39 -0800 | [diff] [blame] | 48 | void (*syn_ack_timeout)(struct sock *sk, |
| 49 | struct request_sock *req); |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 50 | }; |
| 51 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 52 | /* struct request_sock - mini sock to represent a connection request |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 53 | */ |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 54 | struct request_sock { |
| 55 | struct request_sock *dl_next; /* Must be first member! */ |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 56 | u16 mss; |
| 57 | u8 retrans; |
Florian Westphal | 4dfc281 | 2008-04-10 03:12:40 -0700 | [diff] [blame] | 58 | u8 cookie_ts; /* syncookie: encode tcpopts in timestamp */ |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 59 | /* The following two fields can be easily recomputed I think -AK */ |
| 60 | u32 window_clamp; /* window clamp at creation time */ |
| 61 | u32 rcv_wnd; /* rcv_wnd offered first time */ |
| 62 | u32 ts_recent; |
| 63 | unsigned long expires; |
Eric Dumazet | 72a3eff | 2006-11-16 02:30:37 -0800 | [diff] [blame] | 64 | const struct request_sock_ops *rsk_ops; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 65 | struct sock *sk; |
Venkat Yekkirala | 4237c75 | 2006-07-24 23:32:50 -0700 | [diff] [blame] | 66 | u32 secid; |
Venkat Yekkirala | 6b87769 | 2006-11-08 17:04:09 -0600 | [diff] [blame] | 67 | u32 peer_secid; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 68 | }; |
| 69 | |
Eric Dumazet | 72a3eff | 2006-11-16 02:30:37 -0800 | [diff] [blame] | 70 | 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] | 71 | { |
Christoph Lameter | 54e6ecb | 2006-12-06 20:33:16 -0800 | [diff] [blame] | 72 | 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] | 73 | |
| 74 | if (req != NULL) |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 75 | req->rsk_ops = ops; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 76 | |
| 77 | return req; |
| 78 | } |
| 79 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 80 | static inline void __reqsk_free(struct request_sock *req) |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 81 | { |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 82 | kmem_cache_free(req->rsk_ops->slab, req); |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 83 | } |
| 84 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 85 | static inline void reqsk_free(struct request_sock *req) |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 86 | { |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 87 | req->rsk_ops->destructor(req); |
| 88 | __reqsk_free(req); |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 89 | } |
| 90 | |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 91 | extern int sysctl_max_syn_backlog; |
| 92 | |
Arnaldo Carvalho de Melo | 2ad69c5 | 2005-06-18 22:48:55 -0700 | [diff] [blame] | 93 | /** struct listen_sock - listen state |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 94 | * |
| 95 | * @max_qlen_log - log_2 of maximal queued SYNs/REQUESTs |
| 96 | */ |
Arnaldo Carvalho de Melo | 2ad69c5 | 2005-06-18 22:48:55 -0700 | [diff] [blame] | 97 | struct listen_sock { |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 98 | u8 max_qlen_log; |
| 99 | /* 3 bytes hole, try to use */ |
| 100 | int qlen; |
| 101 | int qlen_young; |
| 102 | int clock_hand; |
| 103 | u32 hash_rnd; |
Arnaldo Carvalho de Melo | 83e3609 | 2005-08-09 19:33:31 -0700 | [diff] [blame] | 104 | u32 nr_table_entries; |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 105 | struct request_sock *syn_table[0]; |
| 106 | }; |
| 107 | |
| 108 | /** struct request_sock_queue - queue of request_socks |
| 109 | * |
| 110 | * @rskq_accept_head - FIFO head of established children |
| 111 | * @rskq_accept_tail - FIFO tail of established children |
Arnaldo Carvalho de Melo | 295f732 | 2005-08-09 20:11:56 -0700 | [diff] [blame] | 112 | * @rskq_defer_accept - User waits for some data after accept() |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 113 | * @syn_wait_lock - serializer |
| 114 | * |
| 115 | * %syn_wait_lock is necessary only to avoid proc interface having to grab the main |
| 116 | * lock sock while browsing the listening hash (otherwise it's deadlock prone). |
| 117 | * |
| 118 | * This lock is acquired in read mode only from listening_get_next() seq_file |
| 119 | * op and it's acquired in write mode _only_ from code that is actively |
| 120 | * changing rskq_accept_head. All readers that are holding the master sock lock |
| 121 | * don't need to grab this lock in read mode too as rskq_accept_head. writes |
| 122 | * are always protected from the main sock lock. |
| 123 | */ |
| 124 | struct request_sock_queue { |
| 125 | struct request_sock *rskq_accept_head; |
| 126 | struct request_sock *rskq_accept_tail; |
| 127 | rwlock_t syn_wait_lock; |
David S. Miller | ec0a196 | 2008-06-12 16:31:35 -0700 | [diff] [blame] | 128 | u8 rskq_defer_accept; |
| 129 | /* 3 bytes hole, try to pack */ |
Arnaldo Carvalho de Melo | 2ad69c5 | 2005-06-18 22:48:55 -0700 | [diff] [blame] | 130 | struct listen_sock *listen_opt; |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 131 | }; |
| 132 | |
| 133 | extern int reqsk_queue_alloc(struct request_sock_queue *queue, |
Eric Dumazet | 72a3eff | 2006-11-16 02:30:37 -0800 | [diff] [blame] | 134 | unsigned int nr_table_entries); |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 135 | |
Pavel Emelyanov | dab6ba3 | 2007-11-15 02:57:06 -0800 | [diff] [blame] | 136 | extern void __reqsk_queue_destroy(struct request_sock_queue *queue); |
Arnaldo Carvalho de Melo | 83e3609 | 2005-08-09 19:33:31 -0700 | [diff] [blame] | 137 | extern void reqsk_queue_destroy(struct request_sock_queue *queue); |
| 138 | |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 139 | static 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 | |
Norbert Kiesel | 3eb4801 | 2006-03-26 17:39:55 -0800 | [diff] [blame] | 144 | queue->rskq_accept_head = NULL; |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 145 | return req; |
| 146 | } |
| 147 | |
| 148 | static inline int reqsk_queue_empty(struct request_sock_queue *queue) |
| 149 | { |
| 150 | return queue->rskq_accept_head == NULL; |
| 151 | } |
| 152 | |
| 153 | static 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 | |
| 162 | static 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 | |
| 179 | static inline struct request_sock *reqsk_queue_remove(struct request_sock_queue *queue) |
| 180 | { |
| 181 | struct request_sock *req = queue->rskq_accept_head; |
| 182 | |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 183 | WARN_ON(req == NULL); |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 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 | |
| 192 | static 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 | |
Ilpo Järvinen | 547b792 | 2008-07-25 21:43:18 -0700 | [diff] [blame] | 198 | WARN_ON(child == NULL); |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 199 | |
| 200 | sk_acceptq_removed(parent); |
| 201 | __reqsk_free(req); |
| 202 | return child; |
| 203 | } |
| 204 | |
| 205 | static inline int reqsk_queue_removed(struct request_sock_queue *queue, |
| 206 | struct request_sock *req) |
| 207 | { |
Arnaldo Carvalho de Melo | 2ad69c5 | 2005-06-18 22:48:55 -0700 | [diff] [blame] | 208 | struct listen_sock *lopt = queue->listen_opt; |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 209 | |
| 210 | if (req->retrans == 0) |
| 211 | --lopt->qlen_young; |
| 212 | |
| 213 | return --lopt->qlen; |
| 214 | } |
| 215 | |
| 216 | static inline int reqsk_queue_added(struct request_sock_queue *queue) |
| 217 | { |
Arnaldo Carvalho de Melo | 2ad69c5 | 2005-06-18 22:48:55 -0700 | [diff] [blame] | 218 | struct listen_sock *lopt = queue->listen_opt; |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 219 | const int prev_qlen = lopt->qlen; |
| 220 | |
| 221 | lopt->qlen_young++; |
| 222 | lopt->qlen++; |
| 223 | return prev_qlen; |
| 224 | } |
| 225 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 226 | 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] | 227 | { |
| 228 | return queue->listen_opt != NULL ? queue->listen_opt->qlen : 0; |
| 229 | } |
| 230 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 231 | 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] | 232 | { |
| 233 | return queue->listen_opt->qlen_young; |
| 234 | } |
| 235 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 236 | 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] | 237 | { |
| 238 | return queue->listen_opt->qlen >> queue->listen_opt->max_qlen_log; |
| 239 | } |
| 240 | |
| 241 | static inline void reqsk_queue_hash_req(struct request_sock_queue *queue, |
| 242 | u32 hash, struct request_sock *req, |
Arnaldo Carvalho de Melo | 8129765 | 2005-12-13 23:15:24 -0800 | [diff] [blame] | 243 | unsigned long timeout) |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 244 | { |
Arnaldo Carvalho de Melo | 2ad69c5 | 2005-06-18 22:48:55 -0700 | [diff] [blame] | 245 | struct listen_sock *lopt = queue->listen_opt; |
Arnaldo Carvalho de Melo | 0e87506 | 2005-06-18 22:47:59 -0700 | [diff] [blame] | 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 | |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 257 | #endif /* _REQUEST_SOCK_H */ |