/* * NET Generic infrastructure for Network protocols. * * Definitions for request_sock * * Authors: Arnaldo Carvalho de Melo * * From code originally in include/net/tcp.h * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #ifndef _REQUEST_SOCK_H #define _REQUEST_SOCK_H #include #include #include #include #include struct request_sock; struct sk_buff; struct dst_entry; struct proto; struct request_sock_ops { int family; int obj_size; struct kmem_cache *slab; char *slab_name; int (*rtx_syn_ack)(const struct sock *sk, struct request_sock *req); void (*send_ack)(const struct sock *sk, struct sk_buff *skb, struct request_sock *req); void (*send_reset)(const struct sock *sk, struct sk_buff *skb); void (*destructor)(struct request_sock *req); void (*syn_ack_timeout)(const struct request_sock *req); }; int inet_rtx_syn_ack(const struct sock *parent, struct request_sock *req); /* struct request_sock - mini sock to represent a connection request */ struct request_sock { struct sock_common __req_common; #define rsk_refcnt __req_common.skc_refcnt #define rsk_hash __req_common.skc_hash #define rsk_listener __req_common.skc_listener #define rsk_window_clamp __req_common.skc_window_clamp #define rsk_rcv_wnd __req_common.skc_rcv_wnd struct request_sock *dl_next; u16 mss; u8 num_retrans; /* number of retransmits */ u8 cookie_ts:1; /* syncookie: encode tcpopts in timestamp */ u8 num_timeout:7; /* number of timeouts */ u32 ts_recent; struct timer_list rsk_timer; const struct request_sock_ops *rsk_ops; struct sock *sk; u32 *saved_syn; u32 secid; u32 peer_secid; }; static inline struct request_sock *inet_reqsk(const struct sock *sk) { return (struct request_sock *)sk; } static inline struct sock *req_to_sk(struct request_sock *req) { return (struct sock *)req; } static inline struct request_sock * reqsk_alloc(const struct request_sock_ops *ops, struct sock *sk_listener, bool attach_listener) { struct request_sock *req; req = kmem_cache_alloc(ops->slab, GFP_ATOMIC | __GFP_NOWARN); if (!req) return NULL; req->rsk_listener = NULL; if (attach_listener) { if (unlikely(!atomic_inc_not_zero(&sk_listener->sk_refcnt))) { kmem_cache_free(ops->slab, req); return NULL; } req->rsk_listener = sk_listener; } req->rsk_ops = ops; req_to_sk(req)->sk_prot = sk_listener->sk_prot; sk_node_init(&req_to_sk(req)->sk_node); sk_tx_queue_clear(req_to_sk(req)); req->saved_syn = NULL; atomic_set(&req->rsk_refcnt, 0); return req; } static inline void reqsk_free(struct request_sock *req) { /* temporary debugging */ WARN_ON_ONCE(atomic_read(&req->rsk_refcnt) != 0); req->rsk_ops->destructor(req); if (req->rsk_listener) sock_put(req->rsk_listener); kfree(req->saved_syn); kmem_cache_free(req->rsk_ops->slab, req); } static inline void reqsk_put(struct request_sock *req) { if (atomic_dec_and_test(&req->rsk_refcnt)) reqsk_free(req); } /* * For a TCP Fast Open listener - * lock - protects the access to all the reqsk, which is co-owned by * the listener and the child socket. * qlen - pending TFO requests (still in TCP_SYN_RECV). * max_qlen - max TFO reqs allowed before TFO is disabled. * * XXX (TFO) - ideally these fields can be made as part of "listen_sock" * structure above. But there is some implementation difficulty due to * listen_sock being part of request_sock_queue hence will be freed when * a listener is stopped. But TFO related fields may continue to be * accessed even after a listener is closed, until its sk_refcnt drops * to 0 implying no more outstanding TFO reqs. One solution is to keep * listen_opt around until sk_refcnt drops to 0. But there is some other * complexity that needs to be resolved. E.g., a listener can be disabled * temporarily through shutdown()->tcp_disconnect(), and re-enabled later. */ struct fastopen_queue { struct request_sock *rskq_rst_head; /* Keep track of past TFO */ struct request_sock *rskq_rst_tail; /* requests that caused RST. * This is part of the defense * against spoofing attack. */ spinlock_t lock; int qlen; /* # of pending (TCP_SYN_RECV) reqs */ int max_qlen; /* != 0 iff TFO is currently enabled */ }; /** struct request_sock_queue - queue of request_socks * * @rskq_accept_head - FIFO head of established children * @rskq_accept_tail - FIFO tail of established children * @rskq_defer_accept - User waits for some data after accept() * */ struct request_sock_queue { spinlock_t rskq_lock; u8 rskq_defer_accept; u32 synflood_warned; atomic_t qlen; atomic_t young; struct request_sock *rskq_accept_head; struct request_sock *rskq_accept_tail; struct fastopen_queue fastopenq; /* Check max_qlen != 0 to determine * if TFO is enabled. */ }; void reqsk_queue_alloc(struct request_sock_queue *queue); void reqsk_fastopen_remove(struct sock *sk, struct request_sock *req, bool reset); static inline bool reqsk_queue_empty(const struct request_sock_queue *queue) { return queue->rskq_accept_head == NULL; } static inline struct request_sock *reqsk_queue_remove(struct request_sock_queue *queue, struct sock *parent) { struct request_sock *req; spin_lock_bh(&queue->rskq_lock); req = queue->rskq_accept_head; if (req) { sk_acceptq_removed(parent); queue->rskq_accept_head = req->dl_next; if (queue->rskq_accept_head == NULL) queue->rskq_accept_tail = NULL; } spin_unlock_bh(&queue->rskq_lock); return req; } static inline void reqsk_queue_removed(struct request_sock_queue *queue, const struct request_sock *req) { if (req->num_timeout == 0) atomic_dec(&queue->young); atomic_dec(&queue->qlen); } static inline void reqsk_queue_added(struct request_sock_queue *queue) { atomic_inc(&queue->young); atomic_inc(&queue->qlen); } static inline int reqsk_queue_len(const struct request_sock_queue *queue) { return atomic_read(&queue->qlen); } static inline int reqsk_queue_len_young(const struct request_sock_queue *queue) { return atomic_read(&queue->young); } #endif /* _REQUEST_SOCK_H */ s='ls-size'>1668logplain -rw-r--r--ak4113.h11112logplain -rw-r--r--ak4114.h10424logplain -rw-r--r--ak4117.h9193logplain -rw-r--r--ak4531_codec.h3173logplain -rw-r--r--ak4641.h622logplain -rw-r--r--ak4xxx-adda.h3416logplain -rw-r--r--alc5623.h497logplain -rw-r--r--asequencer.h3670logplain -rw-r--r--asound.h1285logplain -rw-r--r--asoundef.h17098logplain -rw-r--r--atmel-abdac.h639logplain -rw-r--r--atmel-ac97c.h1342logplain -rw-r--r--compress_driver.h6772logplain -rw-r--r--control.h8704logplain -rw-r--r--core.h14380logplain -rw-r--r--cs35l33.h1034logplain -rw-r--r--cs35l34.h887logplain -rw-r--r--cs4231-regs.h8480logplain -rw-r--r--cs4271.h1417logplain -rw-r--r--cs42l52.h738logplain -rw-r--r--cs42l56.h1192logplain -rw-r--r--cs42l73.h507logplain -rw-r--r--cs8403.h8833logplain -rw-r--r--cs8427.h10649logplain -rw-r--r--da7213.h1178logplain -rw-r--r--da7218.h2681logplain -rw-r--r--da7219-aad.h2476logplain -rw-r--r--da7219.h1064logplain -rw-r--r--da9055.h914logplain -rw-r--r--designware_i2s.h2249logplain -rw-r--r--dmaengine_pcm.h6157logplain -rw-r--r--emu10k1.h91396logplain -rw-r--r--emu10k1_synth.h1382logplain -rw-r--r--emu8000.h4109logplain -rw-r--r--emu8000_reg.h10459logplain -rw-r--r--emux_legacy.h5503logplain -rw-r--r--emux_synth.h7649logplain -rw-r--r--es1688.h3618logplain -rw-r--r--gus.h20691logplain -rw-r--r--hda_chmap.h2621logplain -rw-r--r--hda_hwdep.h1412logplain -rw-r--r--hda_i915.h1645logplain -rw-r--r--hda_register.h9475logplain -rw-r--r--hda_regmap.h6714logplain -rw-r--r--hda_verbs.h17130logplain -rw-r--r--hdaudio.h18455logplain -rw-r--r--hdaudio_ext.h7119logplain -rw-r--r--hdmi-codec.h2290logplain -rw-r--r--hwdep.h2624logplain -rw-r--r--i2c.h3555logplain -rw-r--r--info.h7584logplain