2005-04-17 00:20:36 +02:00
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/*
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* INET An implementation of the TCP/IP protocol suite for the LINUX
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* operating system. INET is implemented using the BSD Socket
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* interface as the means of communication with the user level.
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*
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* Definitions for the TCP module.
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*
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* Version: @(#)tcp.h 1.0.5 05/23/93
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*
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2005-05-06 01:16:16 +02:00
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* Authors: Ross Biro
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2005-04-17 00:20:36 +02:00
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* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#ifndef _TCP_H
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#define _TCP_H
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#define TCP_DEBUG 1
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#define FASTRETRANS_DEBUG 1
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/* Cancel timers, when they are not required. */
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#undef TCP_CLEAR_TIMERS
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#include <linux/config.h>
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#include <linux/list.h>
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#include <linux/tcp.h>
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#include <linux/slab.h>
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#include <linux/cache.h>
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#include <linux/percpu.h>
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#include <net/checksum.h>
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[NET] Generalise TCP's struct open_request minisock infrastructure
Kept this first changeset minimal, without changing existing names to
ease peer review.
Basicaly tcp_openreq_alloc now receives the or_calltable, that in turn
has two new members:
->slab, that replaces tcp_openreq_cachep
->obj_size, to inform the size of the openreq descendant for
a specific protocol
The protocol specific fields in struct open_request were moved to a
class hierarchy, with the things that are common to all connection
oriented PF_INET protocols in struct inet_request_sock, the TCP ones
in tcp_request_sock, that is an inet_request_sock, that is an
open_request.
I.e. this uses the same approach used for the struct sock class
hierarchy, with sk_prot indicating if the protocol wants to use the
open_request infrastructure by filling in sk_prot->rsk_prot with an
or_calltable.
Results? Performance is improved and TCP v4 now uses only 64 bytes per
open request minisock, down from 96 without this patch :-)
Next changeset will rename some of the structs, fields and functions
mentioned above, struct or_calltable is way unclear, better name it
struct request_sock_ops, s/struct open_request/struct request_sock/g,
etc.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-19 07:46:52 +02:00
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#include <net/request_sock.h>
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2005-04-17 00:20:36 +02:00
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#include <net/sock.h>
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#include <net/snmp.h>
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#include <net/ip.h>
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#if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
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#include <linux/ipv6.h>
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#endif
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#include <linux/seq_file.h>
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/* This is for all connections with a full identity, no wildcards.
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* New scheme, half the table is for TIME_WAIT, the other half is
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* for the rest. I'll experiment with dynamic table growth later.
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*/
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struct tcp_ehash_bucket {
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rwlock_t lock;
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struct hlist_head chain;
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} __attribute__((__aligned__(8)));
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/* This is for listening sockets, thus all sockets which possess wildcards. */
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#define TCP_LHTABLE_SIZE 32 /* Yes, really, this is all you need. */
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/* There are a few simple rules, which allow for local port reuse by
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* an application. In essence:
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*
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* 1) Sockets bound to different interfaces may share a local port.
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* Failing that, goto test 2.
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* 2) If all sockets have sk->sk_reuse set, and none of them are in
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* TCP_LISTEN state, the port may be shared.
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* Failing that, goto test 3.
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* 3) If all sockets are bound to a specific inet_sk(sk)->rcv_saddr local
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* address, and none of them are the same, the port may be
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* shared.
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* Failing this, the port cannot be shared.
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*
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* The interesting point, is test #2. This is what an FTP server does
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* all day. To optimize this case we use a specific flag bit defined
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* below. As we add sockets to a bind bucket list, we perform a
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* check of: (newsk->sk_reuse && (newsk->sk_state != TCP_LISTEN))
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* As long as all sockets added to a bind bucket pass this test,
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* the flag bit will be set.
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* The resulting situation is that tcp_v[46]_verify_bind() can just check
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* for this flag bit, if it is set and the socket trying to bind has
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* sk->sk_reuse set, we don't even have to walk the owners list at all,
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* we return that it is ok to bind this socket to the requested local port.
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*
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* Sounds like a lot of work, but it is worth it. In a more naive
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* implementation (ie. current FreeBSD etc.) the entire list of ports
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* must be walked for each data port opened by an ftp server. Needless
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* to say, this does not scale at all. With a couple thousand FTP
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* users logged onto your box, isn't it nice to know that new data
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* ports are created in O(1) time? I thought so. ;-) -DaveM
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*/
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struct tcp_bind_bucket {
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unsigned short port;
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signed short fastreuse;
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struct hlist_node node;
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struct hlist_head owners;
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};
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#define tb_for_each(tb, node, head) hlist_for_each_entry(tb, node, head, node)
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struct tcp_bind_hashbucket {
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spinlock_t lock;
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struct hlist_head chain;
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};
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static inline struct tcp_bind_bucket *__tb_head(struct tcp_bind_hashbucket *head)
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{
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return hlist_entry(head->chain.first, struct tcp_bind_bucket, node);
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}
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static inline struct tcp_bind_bucket *tb_head(struct tcp_bind_hashbucket *head)
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{
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return hlist_empty(&head->chain) ? NULL : __tb_head(head);
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}
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extern struct tcp_hashinfo {
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/* This is for sockets with full identity only. Sockets here will
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* always be without wildcards and will have the following invariant:
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*
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* TCP_ESTABLISHED <= sk->sk_state < TCP_CLOSE
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*
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* First half of the table is for sockets not in TIME_WAIT, second half
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* is for TIME_WAIT sockets only.
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*/
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struct tcp_ehash_bucket *__tcp_ehash;
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/* Ok, let's try this, I give up, we do need a local binding
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* TCP hash as well as the others for fast bind/connect.
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*/
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struct tcp_bind_hashbucket *__tcp_bhash;
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int __tcp_bhash_size;
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int __tcp_ehash_size;
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/* All sockets in TCP_LISTEN state will be in here. This is the only
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* table where wildcard'd TCP sockets can exist. Hash function here
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* is just local port number.
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*/
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struct hlist_head __tcp_listening_hash[TCP_LHTABLE_SIZE];
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/* All the above members are written once at bootup and
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* never written again _or_ are predominantly read-access.
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*
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* Now align to a new cache line as all the following members
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* are often dirty.
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*/
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rwlock_t __tcp_lhash_lock ____cacheline_aligned;
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atomic_t __tcp_lhash_users;
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wait_queue_head_t __tcp_lhash_wait;
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spinlock_t __tcp_portalloc_lock;
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} tcp_hashinfo;
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#define tcp_ehash (tcp_hashinfo.__tcp_ehash)
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#define tcp_bhash (tcp_hashinfo.__tcp_bhash)
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#define tcp_ehash_size (tcp_hashinfo.__tcp_ehash_size)
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#define tcp_bhash_size (tcp_hashinfo.__tcp_bhash_size)
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#define tcp_listening_hash (tcp_hashinfo.__tcp_listening_hash)
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#define tcp_lhash_lock (tcp_hashinfo.__tcp_lhash_lock)
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#define tcp_lhash_users (tcp_hashinfo.__tcp_lhash_users)
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#define tcp_lhash_wait (tcp_hashinfo.__tcp_lhash_wait)
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#define tcp_portalloc_lock (tcp_hashinfo.__tcp_portalloc_lock)
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extern kmem_cache_t *tcp_bucket_cachep;
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extern struct tcp_bind_bucket *tcp_bucket_create(struct tcp_bind_hashbucket *head,
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unsigned short snum);
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extern void tcp_bucket_destroy(struct tcp_bind_bucket *tb);
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extern void tcp_bucket_unlock(struct sock *sk);
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extern int tcp_port_rover;
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/* These are AF independent. */
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static __inline__ int tcp_bhashfn(__u16 lport)
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{
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return (lport & (tcp_bhash_size - 1));
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}
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extern void tcp_bind_hash(struct sock *sk, struct tcp_bind_bucket *tb,
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unsigned short snum);
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#if (BITS_PER_LONG == 64)
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#define TCP_ADDRCMP_ALIGN_BYTES 8
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#else
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#define TCP_ADDRCMP_ALIGN_BYTES 4
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#endif
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/* This is a TIME_WAIT bucket. It works around the memory consumption
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* problems of sockets in such a state on heavily loaded servers, but
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* without violating the protocol specification.
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*/
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struct tcp_tw_bucket {
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/*
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* Now struct sock also uses sock_common, so please just
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* don't add nothing before this first member (__tw_common) --acme
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*/
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struct sock_common __tw_common;
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#define tw_family __tw_common.skc_family
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#define tw_state __tw_common.skc_state
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#define tw_reuse __tw_common.skc_reuse
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#define tw_bound_dev_if __tw_common.skc_bound_dev_if
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#define tw_node __tw_common.skc_node
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#define tw_bind_node __tw_common.skc_bind_node
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#define tw_refcnt __tw_common.skc_refcnt
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volatile unsigned char tw_substate;
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unsigned char tw_rcv_wscale;
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__u16 tw_sport;
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/* Socket demultiplex comparisons on incoming packets. */
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/* these five are in inet_sock */
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__u32 tw_daddr
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__attribute__((aligned(TCP_ADDRCMP_ALIGN_BYTES)));
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__u32 tw_rcv_saddr;
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__u16 tw_dport;
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__u16 tw_num;
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/* And these are ours. */
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int tw_hashent;
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int tw_timeout;
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__u32 tw_rcv_nxt;
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__u32 tw_snd_nxt;
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__u32 tw_rcv_wnd;
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__u32 tw_ts_recent;
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long tw_ts_recent_stamp;
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unsigned long tw_ttd;
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struct tcp_bind_bucket *tw_tb;
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struct hlist_node tw_death_node;
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#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
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struct in6_addr tw_v6_daddr;
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struct in6_addr tw_v6_rcv_saddr;
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int tw_v6_ipv6only;
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#endif
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};
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static __inline__ void tw_add_node(struct tcp_tw_bucket *tw,
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struct hlist_head *list)
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{
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hlist_add_head(&tw->tw_node, list);
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}
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static __inline__ void tw_add_bind_node(struct tcp_tw_bucket *tw,
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struct hlist_head *list)
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{
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hlist_add_head(&tw->tw_bind_node, list);
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}
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static inline int tw_dead_hashed(struct tcp_tw_bucket *tw)
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{
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return tw->tw_death_node.pprev != NULL;
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}
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static __inline__ void tw_dead_node_init(struct tcp_tw_bucket *tw)
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{
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tw->tw_death_node.pprev = NULL;
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}
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static __inline__ void __tw_del_dead_node(struct tcp_tw_bucket *tw)
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{
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__hlist_del(&tw->tw_death_node);
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tw_dead_node_init(tw);
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}
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static __inline__ int tw_del_dead_node(struct tcp_tw_bucket *tw)
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{
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if (tw_dead_hashed(tw)) {
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__tw_del_dead_node(tw);
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return 1;
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}
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return 0;
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}
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#define tw_for_each(tw, node, head) \
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hlist_for_each_entry(tw, node, head, tw_node)
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#define tw_for_each_inmate(tw, node, jail) \
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hlist_for_each_entry(tw, node, jail, tw_death_node)
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#define tw_for_each_inmate_safe(tw, node, safe, jail) \
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hlist_for_each_entry_safe(tw, node, safe, jail, tw_death_node)
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#define tcptw_sk(__sk) ((struct tcp_tw_bucket *)(__sk))
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static inline u32 tcp_v4_rcv_saddr(const struct sock *sk)
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{
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return likely(sk->sk_state != TCP_TIME_WAIT) ?
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inet_sk(sk)->rcv_saddr : tcptw_sk(sk)->tw_rcv_saddr;
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}
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#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
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static inline struct in6_addr *__tcp_v6_rcv_saddr(const struct sock *sk)
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{
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return likely(sk->sk_state != TCP_TIME_WAIT) ?
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&inet6_sk(sk)->rcv_saddr : &tcptw_sk(sk)->tw_v6_rcv_saddr;
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}
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static inline struct in6_addr *tcp_v6_rcv_saddr(const struct sock *sk)
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{
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return sk->sk_family == AF_INET6 ? __tcp_v6_rcv_saddr(sk) : NULL;
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}
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#define tcptw_sk_ipv6only(__sk) (tcptw_sk(__sk)->tw_v6_ipv6only)
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static inline int tcp_v6_ipv6only(const struct sock *sk)
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{
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return likely(sk->sk_state != TCP_TIME_WAIT) ?
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ipv6_only_sock(sk) : tcptw_sk_ipv6only(sk);
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}
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#else
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# define __tcp_v6_rcv_saddr(__sk) NULL
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# define tcp_v6_rcv_saddr(__sk) NULL
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# define tcptw_sk_ipv6only(__sk) 0
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# define tcp_v6_ipv6only(__sk) 0
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#endif
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extern kmem_cache_t *tcp_timewait_cachep;
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static inline void tcp_tw_put(struct tcp_tw_bucket *tw)
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{
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if (atomic_dec_and_test(&tw->tw_refcnt)) {
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#ifdef INET_REFCNT_DEBUG
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printk(KERN_DEBUG "tw_bucket %p released\n", tw);
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#endif
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kmem_cache_free(tcp_timewait_cachep, tw);
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}
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}
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extern atomic_t tcp_orphan_count;
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extern int tcp_tw_count;
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extern void tcp_time_wait(struct sock *sk, int state, int timeo);
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extern void tcp_tw_deschedule(struct tcp_tw_bucket *tw);
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/* Socket demux engine toys. */
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#ifdef __BIG_ENDIAN
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#define TCP_COMBINED_PORTS(__sport, __dport) \
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(((__u32)(__sport)<<16) | (__u32)(__dport))
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|
|
#else /* __LITTLE_ENDIAN */
|
|
|
|
#define TCP_COMBINED_PORTS(__sport, __dport) \
|
|
|
|
(((__u32)(__dport)<<16) | (__u32)(__sport))
|
|
|
|
#endif
|
|
|
|
|
|
|
|
#if (BITS_PER_LONG == 64)
|
|
|
|
#ifdef __BIG_ENDIAN
|
|
|
|
#define TCP_V4_ADDR_COOKIE(__name, __saddr, __daddr) \
|
|
|
|
__u64 __name = (((__u64)(__saddr))<<32)|((__u64)(__daddr));
|
|
|
|
#else /* __LITTLE_ENDIAN */
|
|
|
|
#define TCP_V4_ADDR_COOKIE(__name, __saddr, __daddr) \
|
|
|
|
__u64 __name = (((__u64)(__daddr))<<32)|((__u64)(__saddr));
|
|
|
|
#endif /* __BIG_ENDIAN */
|
|
|
|
#define TCP_IPV4_MATCH(__sk, __cookie, __saddr, __daddr, __ports, __dif)\
|
|
|
|
(((*((__u64 *)&(inet_sk(__sk)->daddr)))== (__cookie)) && \
|
|
|
|
((*((__u32 *)&(inet_sk(__sk)->dport)))== (__ports)) && \
|
|
|
|
(!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
|
|
|
|
#define TCP_IPV4_TW_MATCH(__sk, __cookie, __saddr, __daddr, __ports, __dif)\
|
|
|
|
(((*((__u64 *)&(tcptw_sk(__sk)->tw_daddr))) == (__cookie)) && \
|
|
|
|
((*((__u32 *)&(tcptw_sk(__sk)->tw_dport))) == (__ports)) && \
|
|
|
|
(!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
|
|
|
|
#else /* 32-bit arch */
|
|
|
|
#define TCP_V4_ADDR_COOKIE(__name, __saddr, __daddr)
|
|
|
|
#define TCP_IPV4_MATCH(__sk, __cookie, __saddr, __daddr, __ports, __dif)\
|
|
|
|
((inet_sk(__sk)->daddr == (__saddr)) && \
|
|
|
|
(inet_sk(__sk)->rcv_saddr == (__daddr)) && \
|
|
|
|
((*((__u32 *)&(inet_sk(__sk)->dport)))== (__ports)) && \
|
|
|
|
(!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
|
|
|
|
#define TCP_IPV4_TW_MATCH(__sk, __cookie, __saddr, __daddr, __ports, __dif)\
|
|
|
|
((tcptw_sk(__sk)->tw_daddr == (__saddr)) && \
|
|
|
|
(tcptw_sk(__sk)->tw_rcv_saddr == (__daddr)) && \
|
|
|
|
((*((__u32 *)&(tcptw_sk(__sk)->tw_dport))) == (__ports)) && \
|
|
|
|
(!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
|
|
|
|
#endif /* 64-bit arch */
|
|
|
|
|
|
|
|
#define TCP_IPV6_MATCH(__sk, __saddr, __daddr, __ports, __dif) \
|
|
|
|
(((*((__u32 *)&(inet_sk(__sk)->dport)))== (__ports)) && \
|
|
|
|
((__sk)->sk_family == AF_INET6) && \
|
|
|
|
ipv6_addr_equal(&inet6_sk(__sk)->daddr, (__saddr)) && \
|
|
|
|
ipv6_addr_equal(&inet6_sk(__sk)->rcv_saddr, (__daddr)) && \
|
|
|
|
(!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
|
|
|
|
|
|
|
|
/* These can have wildcards, don't try too hard. */
|
|
|
|
static __inline__ int tcp_lhashfn(unsigned short num)
|
|
|
|
{
|
|
|
|
return num & (TCP_LHTABLE_SIZE - 1);
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ int tcp_sk_listen_hashfn(struct sock *sk)
|
|
|
|
{
|
|
|
|
return tcp_lhashfn(inet_sk(sk)->num);
|
|
|
|
}
|
|
|
|
|
|
|
|
#define MAX_TCP_HEADER (128 + MAX_HEADER)
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Never offer a window over 32767 without using window scaling. Some
|
|
|
|
* poor stacks do signed 16bit maths!
|
|
|
|
*/
|
|
|
|
#define MAX_TCP_WINDOW 32767U
|
|
|
|
|
|
|
|
/* Minimal accepted MSS. It is (60+60+8) - (20+20). */
|
|
|
|
#define TCP_MIN_MSS 88U
|
|
|
|
|
|
|
|
/* Minimal RCV_MSS. */
|
|
|
|
#define TCP_MIN_RCVMSS 536U
|
|
|
|
|
|
|
|
/* After receiving this amount of duplicate ACKs fast retransmit starts. */
|
|
|
|
#define TCP_FASTRETRANS_THRESH 3
|
|
|
|
|
|
|
|
/* Maximal reordering. */
|
|
|
|
#define TCP_MAX_REORDERING 127
|
|
|
|
|
|
|
|
/* Maximal number of ACKs sent quickly to accelerate slow-start. */
|
|
|
|
#define TCP_MAX_QUICKACKS 16U
|
|
|
|
|
|
|
|
/* urg_data states */
|
|
|
|
#define TCP_URG_VALID 0x0100
|
|
|
|
#define TCP_URG_NOTYET 0x0200
|
|
|
|
#define TCP_URG_READ 0x0400
|
|
|
|
|
|
|
|
#define TCP_RETR1 3 /*
|
|
|
|
* This is how many retries it does before it
|
|
|
|
* tries to figure out if the gateway is
|
|
|
|
* down. Minimal RFC value is 3; it corresponds
|
|
|
|
* to ~3sec-8min depending on RTO.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#define TCP_RETR2 15 /*
|
|
|
|
* This should take at least
|
|
|
|
* 90 minutes to time out.
|
|
|
|
* RFC1122 says that the limit is 100 sec.
|
|
|
|
* 15 is ~13-30min depending on RTO.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#define TCP_SYN_RETRIES 5 /* number of times to retry active opening a
|
|
|
|
* connection: ~180sec is RFC minumum */
|
|
|
|
|
|
|
|
#define TCP_SYNACK_RETRIES 5 /* number of times to retry passive opening a
|
|
|
|
* connection: ~180sec is RFC minumum */
|
|
|
|
|
|
|
|
|
|
|
|
#define TCP_ORPHAN_RETRIES 7 /* number of times to retry on an orphaned
|
|
|
|
* socket. 7 is ~50sec-16min.
|
|
|
|
*/
|
|
|
|
|
|
|
|
|
|
|
|
#define TCP_TIMEWAIT_LEN (60*HZ) /* how long to wait to destroy TIME-WAIT
|
|
|
|
* state, about 60 seconds */
|
|
|
|
#define TCP_FIN_TIMEOUT TCP_TIMEWAIT_LEN
|
|
|
|
/* BSD style FIN_WAIT2 deadlock breaker.
|
|
|
|
* It used to be 3min, new value is 60sec,
|
|
|
|
* to combine FIN-WAIT-2 timeout with
|
|
|
|
* TIME-WAIT timer.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#define TCP_DELACK_MAX ((unsigned)(HZ/5)) /* maximal time to delay before sending an ACK */
|
|
|
|
#if HZ >= 100
|
|
|
|
#define TCP_DELACK_MIN ((unsigned)(HZ/25)) /* minimal time to delay before sending an ACK */
|
|
|
|
#define TCP_ATO_MIN ((unsigned)(HZ/25))
|
|
|
|
#else
|
|
|
|
#define TCP_DELACK_MIN 4U
|
|
|
|
#define TCP_ATO_MIN 4U
|
|
|
|
#endif
|
|
|
|
#define TCP_RTO_MAX ((unsigned)(120*HZ))
|
|
|
|
#define TCP_RTO_MIN ((unsigned)(HZ/5))
|
|
|
|
#define TCP_TIMEOUT_INIT ((unsigned)(3*HZ)) /* RFC 1122 initial RTO value */
|
|
|
|
|
|
|
|
#define TCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ/2U)) /* Maximal interval between probes
|
|
|
|
* for local resources.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#define TCP_KEEPALIVE_TIME (120*60*HZ) /* two hours */
|
|
|
|
#define TCP_KEEPALIVE_PROBES 9 /* Max of 9 keepalive probes */
|
|
|
|
#define TCP_KEEPALIVE_INTVL (75*HZ)
|
|
|
|
|
|
|
|
#define MAX_TCP_KEEPIDLE 32767
|
|
|
|
#define MAX_TCP_KEEPINTVL 32767
|
|
|
|
#define MAX_TCP_KEEPCNT 127
|
|
|
|
#define MAX_TCP_SYNCNT 127
|
|
|
|
|
|
|
|
#define TCP_SYNQ_INTERVAL (HZ/5) /* Period of SYNACK timer */
|
|
|
|
#define TCP_SYNQ_HSIZE 512 /* Size of SYNACK hash table */
|
|
|
|
|
|
|
|
#define TCP_PAWS_24DAYS (60 * 60 * 24 * 24)
|
|
|
|
#define TCP_PAWS_MSL 60 /* Per-host timestamps are invalidated
|
|
|
|
* after this time. It should be equal
|
|
|
|
* (or greater than) TCP_TIMEWAIT_LEN
|
|
|
|
* to provide reliability equal to one
|
|
|
|
* provided by timewait state.
|
|
|
|
*/
|
|
|
|
#define TCP_PAWS_WINDOW 1 /* Replay window for per-host
|
|
|
|
* timestamps. It must be less than
|
|
|
|
* minimal timewait lifetime.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#define TCP_TW_RECYCLE_SLOTS_LOG 5
|
|
|
|
#define TCP_TW_RECYCLE_SLOTS (1<<TCP_TW_RECYCLE_SLOTS_LOG)
|
|
|
|
|
|
|
|
/* If time > 4sec, it is "slow" path, no recycling is required,
|
|
|
|
so that we select tick to get range about 4 seconds.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#if HZ <= 16 || HZ > 4096
|
|
|
|
# error Unsupported: HZ <= 16 or HZ > 4096
|
|
|
|
#elif HZ <= 32
|
|
|
|
# define TCP_TW_RECYCLE_TICK (5+2-TCP_TW_RECYCLE_SLOTS_LOG)
|
|
|
|
#elif HZ <= 64
|
|
|
|
# define TCP_TW_RECYCLE_TICK (6+2-TCP_TW_RECYCLE_SLOTS_LOG)
|
|
|
|
#elif HZ <= 128
|
|
|
|
# define TCP_TW_RECYCLE_TICK (7+2-TCP_TW_RECYCLE_SLOTS_LOG)
|
|
|
|
#elif HZ <= 256
|
|
|
|
# define TCP_TW_RECYCLE_TICK (8+2-TCP_TW_RECYCLE_SLOTS_LOG)
|
|
|
|
#elif HZ <= 512
|
|
|
|
# define TCP_TW_RECYCLE_TICK (9+2-TCP_TW_RECYCLE_SLOTS_LOG)
|
|
|
|
#elif HZ <= 1024
|
|
|
|
# define TCP_TW_RECYCLE_TICK (10+2-TCP_TW_RECYCLE_SLOTS_LOG)
|
|
|
|
#elif HZ <= 2048
|
|
|
|
# define TCP_TW_RECYCLE_TICK (11+2-TCP_TW_RECYCLE_SLOTS_LOG)
|
|
|
|
#else
|
|
|
|
# define TCP_TW_RECYCLE_TICK (12+2-TCP_TW_RECYCLE_SLOTS_LOG)
|
|
|
|
#endif
|
|
|
|
/*
|
|
|
|
* TCP option
|
|
|
|
*/
|
|
|
|
|
|
|
|
#define TCPOPT_NOP 1 /* Padding */
|
|
|
|
#define TCPOPT_EOL 0 /* End of options */
|
|
|
|
#define TCPOPT_MSS 2 /* Segment size negotiating */
|
|
|
|
#define TCPOPT_WINDOW 3 /* Window scaling */
|
|
|
|
#define TCPOPT_SACK_PERM 4 /* SACK Permitted */
|
|
|
|
#define TCPOPT_SACK 5 /* SACK Block */
|
|
|
|
#define TCPOPT_TIMESTAMP 8 /* Better RTT estimations/PAWS */
|
|
|
|
|
|
|
|
/*
|
|
|
|
* TCP option lengths
|
|
|
|
*/
|
|
|
|
|
|
|
|
#define TCPOLEN_MSS 4
|
|
|
|
#define TCPOLEN_WINDOW 3
|
|
|
|
#define TCPOLEN_SACK_PERM 2
|
|
|
|
#define TCPOLEN_TIMESTAMP 10
|
|
|
|
|
|
|
|
/* But this is what stacks really send out. */
|
|
|
|
#define TCPOLEN_TSTAMP_ALIGNED 12
|
|
|
|
#define TCPOLEN_WSCALE_ALIGNED 4
|
|
|
|
#define TCPOLEN_SACKPERM_ALIGNED 4
|
|
|
|
#define TCPOLEN_SACK_BASE 2
|
|
|
|
#define TCPOLEN_SACK_BASE_ALIGNED 4
|
|
|
|
#define TCPOLEN_SACK_PERBLOCK 8
|
|
|
|
|
|
|
|
#define TCP_TIME_RETRANS 1 /* Retransmit timer */
|
|
|
|
#define TCP_TIME_DACK 2 /* Delayed ack timer */
|
|
|
|
#define TCP_TIME_PROBE0 3 /* Zero window probe timer */
|
|
|
|
#define TCP_TIME_KEEPOPEN 4 /* Keepalive timer */
|
|
|
|
|
|
|
|
/* Flags in tp->nonagle */
|
|
|
|
#define TCP_NAGLE_OFF 1 /* Nagle's algo is disabled */
|
|
|
|
#define TCP_NAGLE_CORK 2 /* Socket is corked */
|
|
|
|
#define TCP_NAGLE_PUSH 4 /* Cork is overriden for already queued data */
|
|
|
|
|
|
|
|
/* sysctl variables for tcp */
|
|
|
|
extern int sysctl_tcp_timestamps;
|
|
|
|
extern int sysctl_tcp_window_scaling;
|
|
|
|
extern int sysctl_tcp_sack;
|
|
|
|
extern int sysctl_tcp_fin_timeout;
|
|
|
|
extern int sysctl_tcp_tw_recycle;
|
|
|
|
extern int sysctl_tcp_keepalive_time;
|
|
|
|
extern int sysctl_tcp_keepalive_probes;
|
|
|
|
extern int sysctl_tcp_keepalive_intvl;
|
|
|
|
extern int sysctl_tcp_syn_retries;
|
|
|
|
extern int sysctl_tcp_synack_retries;
|
|
|
|
extern int sysctl_tcp_retries1;
|
|
|
|
extern int sysctl_tcp_retries2;
|
|
|
|
extern int sysctl_tcp_orphan_retries;
|
|
|
|
extern int sysctl_tcp_syncookies;
|
|
|
|
extern int sysctl_tcp_retrans_collapse;
|
|
|
|
extern int sysctl_tcp_stdurg;
|
|
|
|
extern int sysctl_tcp_rfc1337;
|
|
|
|
extern int sysctl_tcp_abort_on_overflow;
|
|
|
|
extern int sysctl_tcp_max_orphans;
|
|
|
|
extern int sysctl_tcp_max_tw_buckets;
|
|
|
|
extern int sysctl_tcp_fack;
|
|
|
|
extern int sysctl_tcp_reordering;
|
|
|
|
extern int sysctl_tcp_ecn;
|
|
|
|
extern int sysctl_tcp_dsack;
|
|
|
|
extern int sysctl_tcp_mem[3];
|
|
|
|
extern int sysctl_tcp_wmem[3];
|
|
|
|
extern int sysctl_tcp_rmem[3];
|
|
|
|
extern int sysctl_tcp_app_win;
|
|
|
|
extern int sysctl_tcp_adv_win_scale;
|
|
|
|
extern int sysctl_tcp_tw_reuse;
|
|
|
|
extern int sysctl_tcp_frto;
|
|
|
|
extern int sysctl_tcp_low_latency;
|
|
|
|
extern int sysctl_tcp_nometrics_save;
|
|
|
|
extern int sysctl_tcp_moderate_rcvbuf;
|
|
|
|
extern int sysctl_tcp_tso_win_divisor;
|
|
|
|
|
|
|
|
extern atomic_t tcp_memory_allocated;
|
|
|
|
extern atomic_t tcp_sockets_allocated;
|
|
|
|
extern int tcp_memory_pressure;
|
|
|
|
|
|
|
|
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
|
|
|
|
#define TCP_INET_FAMILY(fam) ((fam) == AF_INET)
|
|
|
|
#else
|
|
|
|
#define TCP_INET_FAMILY(fam) 1
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Pointers to address related TCP functions
|
|
|
|
* (i.e. things that depend on the address family)
|
|
|
|
*/
|
|
|
|
|
|
|
|
struct tcp_func {
|
|
|
|
int (*queue_xmit) (struct sk_buff *skb,
|
|
|
|
int ipfragok);
|
|
|
|
|
|
|
|
void (*send_check) (struct sock *sk,
|
|
|
|
struct tcphdr *th,
|
|
|
|
int len,
|
|
|
|
struct sk_buff *skb);
|
|
|
|
|
|
|
|
int (*rebuild_header) (struct sock *sk);
|
|
|
|
|
|
|
|
int (*conn_request) (struct sock *sk,
|
|
|
|
struct sk_buff *skb);
|
|
|
|
|
|
|
|
struct sock * (*syn_recv_sock) (struct sock *sk,
|
|
|
|
struct sk_buff *skb,
|
2005-06-19 07:47:21 +02:00
|
|
|
struct request_sock *req,
|
2005-04-17 00:20:36 +02:00
|
|
|
struct dst_entry *dst);
|
|
|
|
|
|
|
|
int (*remember_stamp) (struct sock *sk);
|
|
|
|
|
|
|
|
__u16 net_header_len;
|
|
|
|
|
|
|
|
int (*setsockopt) (struct sock *sk,
|
|
|
|
int level,
|
|
|
|
int optname,
|
|
|
|
char __user *optval,
|
|
|
|
int optlen);
|
|
|
|
|
|
|
|
int (*getsockopt) (struct sock *sk,
|
|
|
|
int level,
|
|
|
|
int optname,
|
|
|
|
char __user *optval,
|
|
|
|
int __user *optlen);
|
|
|
|
|
|
|
|
|
|
|
|
void (*addr2sockaddr) (struct sock *sk,
|
|
|
|
struct sockaddr *);
|
|
|
|
|
|
|
|
int sockaddr_len;
|
|
|
|
};
|
|
|
|
|
|
|
|
/*
|
|
|
|
* The next routines deal with comparing 32 bit unsigned ints
|
|
|
|
* and worry about wraparound (automatic with unsigned arithmetic).
|
|
|
|
*/
|
|
|
|
|
|
|
|
static inline int before(__u32 seq1, __u32 seq2)
|
|
|
|
{
|
|
|
|
return (__s32)(seq1-seq2) < 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int after(__u32 seq1, __u32 seq2)
|
|
|
|
{
|
|
|
|
return (__s32)(seq2-seq1) < 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
/* is s2<=s1<=s3 ? */
|
|
|
|
static inline int between(__u32 seq1, __u32 seq2, __u32 seq3)
|
|
|
|
{
|
|
|
|
return seq3 - seq2 >= seq1 - seq2;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
extern struct proto tcp_prot;
|
|
|
|
|
|
|
|
DECLARE_SNMP_STAT(struct tcp_mib, tcp_statistics);
|
|
|
|
#define TCP_INC_STATS(field) SNMP_INC_STATS(tcp_statistics, field)
|
|
|
|
#define TCP_INC_STATS_BH(field) SNMP_INC_STATS_BH(tcp_statistics, field)
|
|
|
|
#define TCP_INC_STATS_USER(field) SNMP_INC_STATS_USER(tcp_statistics, field)
|
|
|
|
#define TCP_DEC_STATS(field) SNMP_DEC_STATS(tcp_statistics, field)
|
|
|
|
#define TCP_ADD_STATS_BH(field, val) SNMP_ADD_STATS_BH(tcp_statistics, field, val)
|
|
|
|
#define TCP_ADD_STATS_USER(field, val) SNMP_ADD_STATS_USER(tcp_statistics, field, val)
|
|
|
|
|
|
|
|
extern void tcp_put_port(struct sock *sk);
|
|
|
|
extern void tcp_inherit_port(struct sock *sk, struct sock *child);
|
|
|
|
|
|
|
|
extern void tcp_v4_err(struct sk_buff *skb, u32);
|
|
|
|
|
|
|
|
extern void tcp_shutdown (struct sock *sk, int how);
|
|
|
|
|
|
|
|
extern int tcp_v4_rcv(struct sk_buff *skb);
|
|
|
|
|
|
|
|
extern int tcp_v4_remember_stamp(struct sock *sk);
|
|
|
|
|
|
|
|
extern int tcp_v4_tw_remember_stamp(struct tcp_tw_bucket *tw);
|
|
|
|
|
|
|
|
extern int tcp_sendmsg(struct kiocb *iocb, struct sock *sk,
|
|
|
|
struct msghdr *msg, size_t size);
|
|
|
|
extern ssize_t tcp_sendpage(struct socket *sock, struct page *page, int offset, size_t size, int flags);
|
|
|
|
|
|
|
|
extern int tcp_ioctl(struct sock *sk,
|
|
|
|
int cmd,
|
|
|
|
unsigned long arg);
|
|
|
|
|
|
|
|
extern int tcp_rcv_state_process(struct sock *sk,
|
|
|
|
struct sk_buff *skb,
|
|
|
|
struct tcphdr *th,
|
|
|
|
unsigned len);
|
|
|
|
|
|
|
|
extern int tcp_rcv_established(struct sock *sk,
|
|
|
|
struct sk_buff *skb,
|
|
|
|
struct tcphdr *th,
|
|
|
|
unsigned len);
|
|
|
|
|
|
|
|
extern void tcp_rcv_space_adjust(struct sock *sk);
|
|
|
|
|
|
|
|
enum tcp_ack_state_t
|
|
|
|
{
|
|
|
|
TCP_ACK_SCHED = 1,
|
|
|
|
TCP_ACK_TIMER = 2,
|
|
|
|
TCP_ACK_PUSHED= 4
|
|
|
|
};
|
|
|
|
|
|
|
|
static inline void tcp_schedule_ack(struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
tp->ack.pending |= TCP_ACK_SCHED;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int tcp_ack_scheduled(struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
return tp->ack.pending&TCP_ACK_SCHED;
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ void tcp_dec_quickack_mode(struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
if (tp->ack.quick && --tp->ack.quick == 0) {
|
|
|
|
/* Leaving quickack mode we deflate ATO. */
|
|
|
|
tp->ack.ato = TCP_ATO_MIN;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
extern void tcp_enter_quickack_mode(struct tcp_sock *tp);
|
|
|
|
|
|
|
|
static __inline__ void tcp_delack_init(struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
memset(&tp->ack, 0, sizeof(tp->ack));
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void tcp_clear_options(struct tcp_options_received *rx_opt)
|
|
|
|
{
|
|
|
|
rx_opt->tstamp_ok = rx_opt->sack_ok = rx_opt->wscale_ok = rx_opt->snd_wscale = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
enum tcp_tw_status
|
|
|
|
{
|
|
|
|
TCP_TW_SUCCESS = 0,
|
|
|
|
TCP_TW_RST = 1,
|
|
|
|
TCP_TW_ACK = 2,
|
|
|
|
TCP_TW_SYN = 3
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
|
|
extern enum tcp_tw_status tcp_timewait_state_process(struct tcp_tw_bucket *tw,
|
|
|
|
struct sk_buff *skb,
|
|
|
|
struct tcphdr *th,
|
|
|
|
unsigned len);
|
|
|
|
|
|
|
|
extern struct sock * tcp_check_req(struct sock *sk,struct sk_buff *skb,
|
2005-06-19 07:47:21 +02:00
|
|
|
struct request_sock *req,
|
|
|
|
struct request_sock **prev);
|
2005-04-17 00:20:36 +02:00
|
|
|
extern int tcp_child_process(struct sock *parent,
|
|
|
|
struct sock *child,
|
|
|
|
struct sk_buff *skb);
|
|
|
|
extern void tcp_enter_frto(struct sock *sk);
|
|
|
|
extern void tcp_enter_loss(struct sock *sk, int how);
|
|
|
|
extern void tcp_clear_retrans(struct tcp_sock *tp);
|
|
|
|
extern void tcp_update_metrics(struct sock *sk);
|
|
|
|
|
|
|
|
extern void tcp_close(struct sock *sk,
|
|
|
|
long timeout);
|
|
|
|
extern struct sock * tcp_accept(struct sock *sk, int flags, int *err);
|
|
|
|
extern unsigned int tcp_poll(struct file * file, struct socket *sock, struct poll_table_struct *wait);
|
|
|
|
|
|
|
|
extern int tcp_getsockopt(struct sock *sk, int level,
|
|
|
|
int optname,
|
|
|
|
char __user *optval,
|
|
|
|
int __user *optlen);
|
|
|
|
extern int tcp_setsockopt(struct sock *sk, int level,
|
|
|
|
int optname, char __user *optval,
|
|
|
|
int optlen);
|
|
|
|
extern void tcp_set_keepalive(struct sock *sk, int val);
|
|
|
|
extern int tcp_recvmsg(struct kiocb *iocb, struct sock *sk,
|
|
|
|
struct msghdr *msg,
|
|
|
|
size_t len, int nonblock,
|
|
|
|
int flags, int *addr_len);
|
|
|
|
|
|
|
|
extern int tcp_listen_start(struct sock *sk);
|
|
|
|
|
|
|
|
extern void tcp_parse_options(struct sk_buff *skb,
|
|
|
|
struct tcp_options_received *opt_rx,
|
|
|
|
int estab);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* TCP v4 functions exported for the inet6 API
|
|
|
|
*/
|
|
|
|
|
|
|
|
extern int tcp_v4_rebuild_header(struct sock *sk);
|
|
|
|
|
|
|
|
extern int tcp_v4_build_header(struct sock *sk,
|
|
|
|
struct sk_buff *skb);
|
|
|
|
|
|
|
|
extern void tcp_v4_send_check(struct sock *sk,
|
|
|
|
struct tcphdr *th, int len,
|
|
|
|
struct sk_buff *skb);
|
|
|
|
|
|
|
|
extern int tcp_v4_conn_request(struct sock *sk,
|
|
|
|
struct sk_buff *skb);
|
|
|
|
|
|
|
|
extern struct sock * tcp_create_openreq_child(struct sock *sk,
|
2005-06-19 07:47:21 +02:00
|
|
|
struct request_sock *req,
|
2005-04-17 00:20:36 +02:00
|
|
|
struct sk_buff *skb);
|
|
|
|
|
|
|
|
extern struct sock * tcp_v4_syn_recv_sock(struct sock *sk,
|
|
|
|
struct sk_buff *skb,
|
2005-06-19 07:47:21 +02:00
|
|
|
struct request_sock *req,
|
2005-04-17 00:20:36 +02:00
|
|
|
struct dst_entry *dst);
|
|
|
|
|
|
|
|
extern int tcp_v4_do_rcv(struct sock *sk,
|
|
|
|
struct sk_buff *skb);
|
|
|
|
|
|
|
|
extern int tcp_v4_connect(struct sock *sk,
|
|
|
|
struct sockaddr *uaddr,
|
|
|
|
int addr_len);
|
|
|
|
|
|
|
|
extern int tcp_connect(struct sock *sk);
|
|
|
|
|
|
|
|
extern struct sk_buff * tcp_make_synack(struct sock *sk,
|
|
|
|
struct dst_entry *dst,
|
2005-06-19 07:47:21 +02:00
|
|
|
struct request_sock *req);
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
extern int tcp_disconnect(struct sock *sk, int flags);
|
|
|
|
|
|
|
|
extern void tcp_unhash(struct sock *sk);
|
|
|
|
|
|
|
|
extern int tcp_v4_hash_connecting(struct sock *sk);
|
|
|
|
|
|
|
|
|
|
|
|
/* From syncookies.c */
|
|
|
|
extern struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb,
|
|
|
|
struct ip_options *opt);
|
|
|
|
extern __u32 cookie_v4_init_sequence(struct sock *sk, struct sk_buff *skb,
|
|
|
|
__u16 *mss);
|
|
|
|
|
|
|
|
/* tcp_output.c */
|
|
|
|
|
|
|
|
extern int tcp_write_xmit(struct sock *, int nonagle);
|
|
|
|
extern int tcp_retransmit_skb(struct sock *, struct sk_buff *);
|
|
|
|
extern void tcp_xmit_retransmit_queue(struct sock *);
|
|
|
|
extern void tcp_simple_retransmit(struct sock *);
|
|
|
|
extern int tcp_trim_head(struct sock *, struct sk_buff *, u32);
|
|
|
|
|
|
|
|
extern void tcp_send_probe0(struct sock *);
|
|
|
|
extern void tcp_send_partial(struct sock *);
|
|
|
|
extern int tcp_write_wakeup(struct sock *);
|
|
|
|
extern void tcp_send_fin(struct sock *sk);
|
|
|
|
extern void tcp_send_active_reset(struct sock *sk, int priority);
|
|
|
|
extern int tcp_send_synack(struct sock *);
|
|
|
|
extern void tcp_push_one(struct sock *, unsigned mss_now);
|
|
|
|
extern void tcp_send_ack(struct sock *sk);
|
|
|
|
extern void tcp_send_delayed_ack(struct sock *sk);
|
|
|
|
|
|
|
|
/* tcp_timer.c */
|
|
|
|
extern void tcp_init_xmit_timers(struct sock *);
|
|
|
|
extern void tcp_clear_xmit_timers(struct sock *);
|
|
|
|
|
|
|
|
extern void tcp_delete_keepalive_timer(struct sock *);
|
|
|
|
extern void tcp_reset_keepalive_timer(struct sock *, unsigned long);
|
|
|
|
extern unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu);
|
|
|
|
extern unsigned int tcp_current_mss(struct sock *sk, int large);
|
|
|
|
|
|
|
|
#ifdef TCP_DEBUG
|
|
|
|
extern const char tcp_timer_bug_msg[];
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/* tcp_diag.c */
|
|
|
|
extern void tcp_get_info(struct sock *, struct tcp_info *);
|
|
|
|
|
|
|
|
/* Read 'sendfile()'-style from a TCP socket */
|
|
|
|
typedef int (*sk_read_actor_t)(read_descriptor_t *, struct sk_buff *,
|
|
|
|
unsigned int, size_t);
|
|
|
|
extern int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
|
|
|
|
sk_read_actor_t recv_actor);
|
|
|
|
|
|
|
|
static inline void tcp_clear_xmit_timer(struct sock *sk, int what)
|
|
|
|
{
|
|
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
|
|
|
|
|
|
switch (what) {
|
|
|
|
case TCP_TIME_RETRANS:
|
|
|
|
case TCP_TIME_PROBE0:
|
|
|
|
tp->pending = 0;
|
|
|
|
|
|
|
|
#ifdef TCP_CLEAR_TIMERS
|
|
|
|
sk_stop_timer(sk, &tp->retransmit_timer);
|
|
|
|
#endif
|
|
|
|
break;
|
|
|
|
case TCP_TIME_DACK:
|
|
|
|
tp->ack.blocked = 0;
|
|
|
|
tp->ack.pending = 0;
|
|
|
|
|
|
|
|
#ifdef TCP_CLEAR_TIMERS
|
|
|
|
sk_stop_timer(sk, &tp->delack_timer);
|
|
|
|
#endif
|
|
|
|
break;
|
|
|
|
default:
|
|
|
|
#ifdef TCP_DEBUG
|
|
|
|
printk(tcp_timer_bug_msg);
|
|
|
|
#endif
|
|
|
|
return;
|
|
|
|
};
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Reset the retransmission timer
|
|
|
|
*/
|
|
|
|
static inline void tcp_reset_xmit_timer(struct sock *sk, int what, unsigned long when)
|
|
|
|
{
|
|
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
|
|
|
|
|
|
if (when > TCP_RTO_MAX) {
|
|
|
|
#ifdef TCP_DEBUG
|
|
|
|
printk(KERN_DEBUG "reset_xmit_timer sk=%p %d when=0x%lx, caller=%p\n", sk, what, when, current_text_addr());
|
|
|
|
#endif
|
|
|
|
when = TCP_RTO_MAX;
|
|
|
|
}
|
|
|
|
|
|
|
|
switch (what) {
|
|
|
|
case TCP_TIME_RETRANS:
|
|
|
|
case TCP_TIME_PROBE0:
|
|
|
|
tp->pending = what;
|
|
|
|
tp->timeout = jiffies+when;
|
|
|
|
sk_reset_timer(sk, &tp->retransmit_timer, tp->timeout);
|
|
|
|
break;
|
|
|
|
|
|
|
|
case TCP_TIME_DACK:
|
|
|
|
tp->ack.pending |= TCP_ACK_TIMER;
|
|
|
|
tp->ack.timeout = jiffies+when;
|
|
|
|
sk_reset_timer(sk, &tp->delack_timer, tp->ack.timeout);
|
|
|
|
break;
|
|
|
|
|
|
|
|
default:
|
|
|
|
#ifdef TCP_DEBUG
|
|
|
|
printk(tcp_timer_bug_msg);
|
|
|
|
#endif
|
|
|
|
return;
|
|
|
|
};
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Initialize RCV_MSS value.
|
|
|
|
* RCV_MSS is an our guess about MSS used by the peer.
|
|
|
|
* We haven't any direct information about the MSS.
|
|
|
|
* It's better to underestimate the RCV_MSS rather than overestimate.
|
|
|
|
* Overestimations make us ACKing less frequently than needed.
|
|
|
|
* Underestimations are more easy to detect and fix by tcp_measure_rcv_mss().
|
|
|
|
*/
|
|
|
|
|
|
|
|
static inline void tcp_initialize_rcv_mss(struct sock *sk)
|
|
|
|
{
|
|
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
|
|
unsigned int hint = min(tp->advmss, tp->mss_cache_std);
|
|
|
|
|
|
|
|
hint = min(hint, tp->rcv_wnd/2);
|
|
|
|
hint = min(hint, TCP_MIN_RCVMSS);
|
|
|
|
hint = max(hint, TCP_MIN_MSS);
|
|
|
|
|
|
|
|
tp->ack.rcv_mss = hint;
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ void __tcp_fast_path_on(struct tcp_sock *tp, u32 snd_wnd)
|
|
|
|
{
|
|
|
|
tp->pred_flags = htonl((tp->tcp_header_len << 26) |
|
|
|
|
ntohl(TCP_FLAG_ACK) |
|
|
|
|
snd_wnd);
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ void tcp_fast_path_on(struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
__tcp_fast_path_on(tp, tp->snd_wnd >> tp->rx_opt.snd_wscale);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void tcp_fast_path_check(struct sock *sk, struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
if (skb_queue_len(&tp->out_of_order_queue) == 0 &&
|
|
|
|
tp->rcv_wnd &&
|
|
|
|
atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf &&
|
|
|
|
!tp->urg_data)
|
|
|
|
tcp_fast_path_on(tp);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Compute the actual receive window we are currently advertising.
|
|
|
|
* Rcv_nxt can be after the window if our peer push more data
|
|
|
|
* than the offered window.
|
|
|
|
*/
|
|
|
|
static __inline__ u32 tcp_receive_window(const struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
s32 win = tp->rcv_wup + tp->rcv_wnd - tp->rcv_nxt;
|
|
|
|
|
|
|
|
if (win < 0)
|
|
|
|
win = 0;
|
|
|
|
return (u32) win;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Choose a new window, without checks for shrinking, and without
|
|
|
|
* scaling applied to the result. The caller does these things
|
|
|
|
* if necessary. This is a "raw" window selection.
|
|
|
|
*/
|
|
|
|
extern u32 __tcp_select_window(struct sock *sk);
|
|
|
|
|
|
|
|
/* TCP timestamps are only 32-bits, this causes a slight
|
|
|
|
* complication on 64-bit systems since we store a snapshot
|
|
|
|
* of jiffies in the buffer control blocks below. We decidely
|
|
|
|
* only use of the low 32-bits of jiffies and hide the ugly
|
|
|
|
* casts with the following macro.
|
|
|
|
*/
|
|
|
|
#define tcp_time_stamp ((__u32)(jiffies))
|
|
|
|
|
|
|
|
/* This is what the send packet queueing engine uses to pass
|
|
|
|
* TCP per-packet control information to the transmission
|
|
|
|
* code. We also store the host-order sequence numbers in
|
|
|
|
* here too. This is 36 bytes on 32-bit architectures,
|
|
|
|
* 40 bytes on 64-bit machines, if this grows please adjust
|
|
|
|
* skbuff.h:skbuff->cb[xxx] size appropriately.
|
|
|
|
*/
|
|
|
|
struct tcp_skb_cb {
|
|
|
|
union {
|
|
|
|
struct inet_skb_parm h4;
|
|
|
|
#if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
|
|
|
|
struct inet6_skb_parm h6;
|
|
|
|
#endif
|
|
|
|
} header; /* For incoming frames */
|
|
|
|
__u32 seq; /* Starting sequence number */
|
|
|
|
__u32 end_seq; /* SEQ + FIN + SYN + datalen */
|
|
|
|
__u32 when; /* used to compute rtt's */
|
|
|
|
__u8 flags; /* TCP header flags. */
|
|
|
|
|
|
|
|
/* NOTE: These must match up to the flags byte in a
|
|
|
|
* real TCP header.
|
|
|
|
*/
|
|
|
|
#define TCPCB_FLAG_FIN 0x01
|
|
|
|
#define TCPCB_FLAG_SYN 0x02
|
|
|
|
#define TCPCB_FLAG_RST 0x04
|
|
|
|
#define TCPCB_FLAG_PSH 0x08
|
|
|
|
#define TCPCB_FLAG_ACK 0x10
|
|
|
|
#define TCPCB_FLAG_URG 0x20
|
|
|
|
#define TCPCB_FLAG_ECE 0x40
|
|
|
|
#define TCPCB_FLAG_CWR 0x80
|
|
|
|
|
|
|
|
__u8 sacked; /* State flags for SACK/FACK. */
|
|
|
|
#define TCPCB_SACKED_ACKED 0x01 /* SKB ACK'd by a SACK block */
|
|
|
|
#define TCPCB_SACKED_RETRANS 0x02 /* SKB retransmitted */
|
|
|
|
#define TCPCB_LOST 0x04 /* SKB is lost */
|
|
|
|
#define TCPCB_TAGBITS 0x07 /* All tag bits */
|
|
|
|
|
|
|
|
#define TCPCB_EVER_RETRANS 0x80 /* Ever retransmitted frame */
|
|
|
|
#define TCPCB_RETRANS (TCPCB_SACKED_RETRANS|TCPCB_EVER_RETRANS)
|
|
|
|
|
|
|
|
#define TCPCB_URG 0x20 /* Urgent pointer advenced here */
|
|
|
|
|
|
|
|
#define TCPCB_AT_TAIL (TCPCB_URG)
|
|
|
|
|
|
|
|
__u16 urg_ptr; /* Valid w/URG flags is set. */
|
|
|
|
__u32 ack_seq; /* Sequence number ACK'd */
|
|
|
|
};
|
|
|
|
|
|
|
|
#define TCP_SKB_CB(__skb) ((struct tcp_skb_cb *)&((__skb)->cb[0]))
|
|
|
|
|
|
|
|
#include <net/tcp_ecn.h>
|
|
|
|
|
|
|
|
/* Due to TSO, an SKB can be composed of multiple actual
|
|
|
|
* packets. To keep these tracked properly, we use this.
|
|
|
|
*/
|
|
|
|
static inline int tcp_skb_pcount(const struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
return skb_shinfo(skb)->tso_segs;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* This is valid iff tcp_skb_pcount() > 1. */
|
|
|
|
static inline int tcp_skb_mss(const struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
return skb_shinfo(skb)->tso_size;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void tcp_dec_pcount_approx(__u32 *count,
|
|
|
|
const struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
if (*count) {
|
|
|
|
*count -= tcp_skb_pcount(skb);
|
|
|
|
if ((int)*count < 0)
|
|
|
|
*count = 0;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void tcp_packets_out_inc(struct sock *sk,
|
|
|
|
struct tcp_sock *tp,
|
|
|
|
const struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
int orig = tp->packets_out;
|
|
|
|
|
|
|
|
tp->packets_out += tcp_skb_pcount(skb);
|
|
|
|
if (!orig)
|
|
|
|
tcp_reset_xmit_timer(sk, TCP_TIME_RETRANS, tp->rto);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void tcp_packets_out_dec(struct tcp_sock *tp,
|
|
|
|
const struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
tp->packets_out -= tcp_skb_pcount(skb);
|
|
|
|
}
|
|
|
|
|
2005-06-23 21:19:55 +02:00
|
|
|
/* Events passed to congestion control interface */
|
|
|
|
enum tcp_ca_event {
|
|
|
|
CA_EVENT_TX_START, /* first transmit when no packets in flight */
|
|
|
|
CA_EVENT_CWND_RESTART, /* congestion window restart */
|
|
|
|
CA_EVENT_COMPLETE_CWR, /* end of congestion recovery */
|
|
|
|
CA_EVENT_FRTO, /* fast recovery timeout */
|
|
|
|
CA_EVENT_LOSS, /* loss timeout */
|
|
|
|
CA_EVENT_FAST_ACK, /* in sequence ack */
|
|
|
|
CA_EVENT_SLOW_ACK, /* other ack */
|
|
|
|
};
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Interface for adding new TCP congestion control handlers
|
|
|
|
*/
|
|
|
|
#define TCP_CA_NAME_MAX 16
|
|
|
|
struct tcp_congestion_ops {
|
|
|
|
struct list_head list;
|
|
|
|
|
|
|
|
/* initialize private data (optional) */
|
|
|
|
void (*init)(struct tcp_sock *tp);
|
|
|
|
/* cleanup private data (optional) */
|
|
|
|
void (*release)(struct tcp_sock *tp);
|
|
|
|
|
|
|
|
/* return slow start threshold (required) */
|
|
|
|
u32 (*ssthresh)(struct tcp_sock *tp);
|
|
|
|
/* lower bound for congestion window (optional) */
|
|
|
|
u32 (*min_cwnd)(struct tcp_sock *tp);
|
|
|
|
/* do new cwnd calculation (required) */
|
|
|
|
void (*cong_avoid)(struct tcp_sock *tp, u32 ack,
|
|
|
|
u32 rtt, u32 in_flight, int good_ack);
|
|
|
|
/* round trip time sample per acked packet (optional) */
|
|
|
|
void (*rtt_sample)(struct tcp_sock *tp, u32 usrtt);
|
|
|
|
/* call before changing ca_state (optional) */
|
|
|
|
void (*set_state)(struct tcp_sock *tp, u8 new_state);
|
|
|
|
/* call when cwnd event occurs (optional) */
|
|
|
|
void (*cwnd_event)(struct tcp_sock *tp, enum tcp_ca_event ev);
|
|
|
|
/* new value of cwnd after loss (optional) */
|
|
|
|
u32 (*undo_cwnd)(struct tcp_sock *tp);
|
|
|
|
/* hook for packet ack accounting (optional) */
|
|
|
|
void (*pkts_acked)(struct tcp_sock *tp, u32 num_acked);
|
|
|
|
/* get info for tcp_diag (optional) */
|
|
|
|
void (*get_info)(struct tcp_sock *tp, u32 ext, struct sk_buff *skb);
|
|
|
|
|
|
|
|
char name[TCP_CA_NAME_MAX];
|
|
|
|
struct module *owner;
|
|
|
|
};
|
|
|
|
|
|
|
|
extern int tcp_register_congestion_control(struct tcp_congestion_ops *type);
|
|
|
|
extern void tcp_unregister_congestion_control(struct tcp_congestion_ops *type);
|
|
|
|
|
|
|
|
extern void tcp_init_congestion_control(struct tcp_sock *tp);
|
|
|
|
extern void tcp_cleanup_congestion_control(struct tcp_sock *tp);
|
|
|
|
extern int tcp_set_default_congestion_control(const char *name);
|
|
|
|
extern void tcp_get_default_congestion_control(char *name);
|
2005-06-24 05:37:36 +02:00
|
|
|
extern int tcp_set_congestion_control(struct tcp_sock *tp, const char *name);
|
2005-06-23 21:19:55 +02:00
|
|
|
|
2005-06-24 05:37:36 +02:00
|
|
|
extern struct tcp_congestion_ops tcp_init_congestion_ops;
|
2005-06-23 21:19:55 +02:00
|
|
|
extern u32 tcp_reno_ssthresh(struct tcp_sock *tp);
|
|
|
|
extern void tcp_reno_cong_avoid(struct tcp_sock *tp, u32 ack,
|
|
|
|
u32 rtt, u32 in_flight, int flag);
|
|
|
|
extern u32 tcp_reno_min_cwnd(struct tcp_sock *tp);
|
2005-06-24 08:45:02 +02:00
|
|
|
extern struct tcp_congestion_ops tcp_reno;
|
2005-06-23 21:19:55 +02:00
|
|
|
|
|
|
|
static inline void tcp_set_ca_state(struct tcp_sock *tp, u8 ca_state)
|
|
|
|
{
|
|
|
|
if (tp->ca_ops->set_state)
|
|
|
|
tp->ca_ops->set_state(tp, ca_state);
|
|
|
|
tp->ca_state = ca_state;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void tcp_ca_event(struct tcp_sock *tp, enum tcp_ca_event event)
|
|
|
|
{
|
|
|
|
if (tp->ca_ops->cwnd_event)
|
|
|
|
tp->ca_ops->cwnd_event(tp, event);
|
|
|
|
}
|
|
|
|
|
2005-04-17 00:20:36 +02:00
|
|
|
/* This determines how many packets are "in the network" to the best
|
|
|
|
* of our knowledge. In many cases it is conservative, but where
|
|
|
|
* detailed information is available from the receiver (via SACK
|
|
|
|
* blocks etc.) we can make more aggressive calculations.
|
|
|
|
*
|
|
|
|
* Use this for decisions involving congestion control, use just
|
|
|
|
* tp->packets_out to determine if the send queue is empty or not.
|
|
|
|
*
|
|
|
|
* Read this equation as:
|
|
|
|
*
|
|
|
|
* "Packets sent once on transmission queue" MINUS
|
|
|
|
* "Packets left network, but not honestly ACKed yet" PLUS
|
|
|
|
* "Packets fast retransmitted"
|
|
|
|
*/
|
|
|
|
static __inline__ unsigned int tcp_packets_in_flight(const struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
return (tp->packets_out - tp->left_out + tp->retrans_out);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* If cwnd > ssthresh, we may raise ssthresh to be half-way to cwnd.
|
|
|
|
* The exception is rate halving phase, when cwnd is decreasing towards
|
|
|
|
* ssthresh.
|
|
|
|
*/
|
|
|
|
static inline __u32 tcp_current_ssthresh(struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
if ((1<<tp->ca_state)&(TCPF_CA_CWR|TCPF_CA_Recovery))
|
|
|
|
return tp->snd_ssthresh;
|
|
|
|
else
|
|
|
|
return max(tp->snd_ssthresh,
|
|
|
|
((tp->snd_cwnd >> 1) +
|
|
|
|
(tp->snd_cwnd >> 2)));
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void tcp_sync_left_out(struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
if (tp->rx_opt.sack_ok &&
|
|
|
|
(tp->sacked_out >= tp->packets_out - tp->lost_out))
|
|
|
|
tp->sacked_out = tp->packets_out - tp->lost_out;
|
|
|
|
tp->left_out = tp->sacked_out + tp->lost_out;
|
|
|
|
}
|
|
|
|
|
|
|
|
extern void tcp_cwnd_application_limited(struct sock *sk);
|
|
|
|
|
|
|
|
/* Congestion window validation. (RFC2861) */
|
|
|
|
|
|
|
|
static inline void tcp_cwnd_validate(struct sock *sk, struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
__u32 packets_out = tp->packets_out;
|
|
|
|
|
|
|
|
if (packets_out >= tp->snd_cwnd) {
|
|
|
|
/* Network is feed fully. */
|
|
|
|
tp->snd_cwnd_used = 0;
|
|
|
|
tp->snd_cwnd_stamp = tcp_time_stamp;
|
|
|
|
} else {
|
|
|
|
/* Network starves. */
|
|
|
|
if (tp->packets_out > tp->snd_cwnd_used)
|
|
|
|
tp->snd_cwnd_used = tp->packets_out;
|
|
|
|
|
|
|
|
if ((s32)(tcp_time_stamp - tp->snd_cwnd_stamp) >= tp->rto)
|
|
|
|
tcp_cwnd_application_limited(sk);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Set slow start threshould and cwnd not falling to slow start */
|
|
|
|
static inline void __tcp_enter_cwr(struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
tp->undo_marker = 0;
|
2005-06-23 21:19:55 +02:00
|
|
|
tp->snd_ssthresh = tp->ca_ops->ssthresh(tp);
|
2005-04-17 00:20:36 +02:00
|
|
|
tp->snd_cwnd = min(tp->snd_cwnd,
|
|
|
|
tcp_packets_in_flight(tp) + 1U);
|
|
|
|
tp->snd_cwnd_cnt = 0;
|
|
|
|
tp->high_seq = tp->snd_nxt;
|
|
|
|
tp->snd_cwnd_stamp = tcp_time_stamp;
|
|
|
|
TCP_ECN_queue_cwr(tp);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void tcp_enter_cwr(struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
tp->prior_ssthresh = 0;
|
|
|
|
if (tp->ca_state < TCP_CA_CWR) {
|
|
|
|
__tcp_enter_cwr(tp);
|
|
|
|
tcp_set_ca_state(tp, TCP_CA_CWR);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
extern __u32 tcp_init_cwnd(struct tcp_sock *tp, struct dst_entry *dst);
|
|
|
|
|
|
|
|
/* Slow start with delack produces 3 packets of burst, so that
|
|
|
|
* it is safe "de facto".
|
|
|
|
*/
|
|
|
|
static __inline__ __u32 tcp_max_burst(const struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
return 3;
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ int tcp_minshall_check(const struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
return after(tp->snd_sml,tp->snd_una) &&
|
|
|
|
!after(tp->snd_sml, tp->snd_nxt);
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ void tcp_minshall_update(struct tcp_sock *tp, int mss,
|
|
|
|
const struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
if (skb->len < mss)
|
|
|
|
tp->snd_sml = TCP_SKB_CB(skb)->end_seq;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Return 0, if packet can be sent now without violation Nagle's rules:
|
|
|
|
1. It is full sized.
|
|
|
|
2. Or it contains FIN.
|
|
|
|
3. Or TCP_NODELAY was set.
|
|
|
|
4. Or TCP_CORK is not set, and all sent packets are ACKed.
|
|
|
|
With Minshall's modification: all sent small packets are ACKed.
|
|
|
|
*/
|
|
|
|
|
|
|
|
static __inline__ int
|
|
|
|
tcp_nagle_check(const struct tcp_sock *tp, const struct sk_buff *skb,
|
|
|
|
unsigned mss_now, int nonagle)
|
|
|
|
{
|
|
|
|
return (skb->len < mss_now &&
|
|
|
|
!(TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN) &&
|
|
|
|
((nonagle&TCP_NAGLE_CORK) ||
|
|
|
|
(!nonagle &&
|
|
|
|
tp->packets_out &&
|
|
|
|
tcp_minshall_check(tp))));
|
|
|
|
}
|
|
|
|
|
2005-04-25 04:12:33 +02:00
|
|
|
extern void tcp_set_skb_tso_segs(struct sock *, struct sk_buff *);
|
2005-04-17 00:20:36 +02:00
|
|
|
|
|
|
|
/* This checks if the data bearing packet SKB (usually sk->sk_send_head)
|
|
|
|
* should be put on the wire right now.
|
|
|
|
*/
|
2005-04-25 04:12:33 +02:00
|
|
|
static __inline__ int tcp_snd_test(struct sock *sk,
|
2005-04-17 00:20:36 +02:00
|
|
|
struct sk_buff *skb,
|
|
|
|
unsigned cur_mss, int nonagle)
|
|
|
|
{
|
2005-04-25 04:12:33 +02:00
|
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
2005-04-17 00:20:36 +02:00
|
|
|
int pkts = tcp_skb_pcount(skb);
|
|
|
|
|
|
|
|
if (!pkts) {
|
2005-04-25 04:12:33 +02:00
|
|
|
tcp_set_skb_tso_segs(sk, skb);
|
2005-04-17 00:20:36 +02:00
|
|
|
pkts = tcp_skb_pcount(skb);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* RFC 1122 - section 4.2.3.4
|
|
|
|
*
|
|
|
|
* We must queue if
|
|
|
|
*
|
|
|
|
* a) The right edge of this frame exceeds the window
|
|
|
|
* b) There are packets in flight and we have a small segment
|
|
|
|
* [SWS avoidance and Nagle algorithm]
|
|
|
|
* (part of SWS is done on packetization)
|
|
|
|
* Minshall version sounds: there are no _small_
|
|
|
|
* segments in flight. (tcp_nagle_check)
|
|
|
|
* c) We have too many packets 'in flight'
|
|
|
|
*
|
|
|
|
* Don't use the nagle rule for urgent data (or
|
|
|
|
* for the final FIN -DaveM).
|
|
|
|
*
|
|
|
|
* Also, Nagle rule does not apply to frames, which
|
|
|
|
* sit in the middle of queue (they have no chances
|
|
|
|
* to get new data) and if room at tail of skb is
|
|
|
|
* not enough to save something seriously (<32 for now).
|
|
|
|
*/
|
|
|
|
|
|
|
|
/* Don't be strict about the congestion window for the
|
|
|
|
* final FIN frame. -DaveM
|
|
|
|
*/
|
|
|
|
return (((nonagle&TCP_NAGLE_PUSH) || tp->urg_mode
|
|
|
|
|| !tcp_nagle_check(tp, skb, cur_mss, nonagle)) &&
|
|
|
|
(((tcp_packets_in_flight(tp) + (pkts-1)) < tp->snd_cwnd) ||
|
|
|
|
(TCP_SKB_CB(skb)->flags & TCPCB_FLAG_FIN)) &&
|
|
|
|
!after(TCP_SKB_CB(skb)->end_seq, tp->snd_una + tp->snd_wnd));
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ void tcp_check_probe_timer(struct sock *sk, struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
if (!tp->packets_out && !tp->pending)
|
|
|
|
tcp_reset_xmit_timer(sk, TCP_TIME_PROBE0, tp->rto);
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ int tcp_skb_is_last(const struct sock *sk,
|
|
|
|
const struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
return skb->next == (struct sk_buff *)&sk->sk_write_queue;
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Push out any pending frames which were held back due to
|
|
|
|
* TCP_CORK or attempt at coalescing tiny packets.
|
|
|
|
* The socket must be locked by the caller.
|
|
|
|
*/
|
|
|
|
static __inline__ void __tcp_push_pending_frames(struct sock *sk,
|
|
|
|
struct tcp_sock *tp,
|
|
|
|
unsigned cur_mss,
|
|
|
|
int nonagle)
|
|
|
|
{
|
|
|
|
struct sk_buff *skb = sk->sk_send_head;
|
|
|
|
|
|
|
|
if (skb) {
|
|
|
|
if (!tcp_skb_is_last(sk, skb))
|
|
|
|
nonagle = TCP_NAGLE_PUSH;
|
2005-04-25 04:12:33 +02:00
|
|
|
if (!tcp_snd_test(sk, skb, cur_mss, nonagle) ||
|
2005-04-17 00:20:36 +02:00
|
|
|
tcp_write_xmit(sk, nonagle))
|
|
|
|
tcp_check_probe_timer(sk, tp);
|
|
|
|
}
|
|
|
|
tcp_cwnd_validate(sk, tp);
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ void tcp_push_pending_frames(struct sock *sk,
|
|
|
|
struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
__tcp_push_pending_frames(sk, tp, tcp_current_mss(sk, 1), tp->nonagle);
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ int tcp_may_send_now(struct sock *sk, struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
struct sk_buff *skb = sk->sk_send_head;
|
|
|
|
|
|
|
|
return (skb &&
|
2005-04-25 04:12:33 +02:00
|
|
|
tcp_snd_test(sk, skb, tcp_current_mss(sk, 1),
|
2005-04-17 00:20:36 +02:00
|
|
|
tcp_skb_is_last(sk, skb) ? TCP_NAGLE_PUSH : tp->nonagle));
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ void tcp_init_wl(struct tcp_sock *tp, u32 ack, u32 seq)
|
|
|
|
{
|
|
|
|
tp->snd_wl1 = seq;
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ void tcp_update_wl(struct tcp_sock *tp, u32 ack, u32 seq)
|
|
|
|
{
|
|
|
|
tp->snd_wl1 = seq;
|
|
|
|
}
|
|
|
|
|
|
|
|
extern void tcp_destroy_sock(struct sock *sk);
|
|
|
|
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Calculate(/check) TCP checksum
|
|
|
|
*/
|
|
|
|
static __inline__ u16 tcp_v4_check(struct tcphdr *th, int len,
|
|
|
|
unsigned long saddr, unsigned long daddr,
|
|
|
|
unsigned long base)
|
|
|
|
{
|
|
|
|
return csum_tcpudp_magic(saddr,daddr,len,IPPROTO_TCP,base);
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ int __tcp_checksum_complete(struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
return (unsigned short)csum_fold(skb_checksum(skb, 0, skb->len, skb->csum));
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ int tcp_checksum_complete(struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
return skb->ip_summed != CHECKSUM_UNNECESSARY &&
|
|
|
|
__tcp_checksum_complete(skb);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Prequeue for VJ style copy to user, combined with checksumming. */
|
|
|
|
|
|
|
|
static __inline__ void tcp_prequeue_init(struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
tp->ucopy.task = NULL;
|
|
|
|
tp->ucopy.len = 0;
|
|
|
|
tp->ucopy.memory = 0;
|
|
|
|
skb_queue_head_init(&tp->ucopy.prequeue);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Packet is added to VJ-style prequeue for processing in process
|
|
|
|
* context, if a reader task is waiting. Apparently, this exciting
|
|
|
|
* idea (VJ's mail "Re: query about TCP header on tcp-ip" of 07 Sep 93)
|
|
|
|
* failed somewhere. Latency? Burstiness? Well, at least now we will
|
|
|
|
* see, why it failed. 8)8) --ANK
|
|
|
|
*
|
|
|
|
* NOTE: is this not too big to inline?
|
|
|
|
*/
|
|
|
|
static __inline__ int tcp_prequeue(struct sock *sk, struct sk_buff *skb)
|
|
|
|
{
|
|
|
|
struct tcp_sock *tp = tcp_sk(sk);
|
|
|
|
|
|
|
|
if (!sysctl_tcp_low_latency && tp->ucopy.task) {
|
|
|
|
__skb_queue_tail(&tp->ucopy.prequeue, skb);
|
|
|
|
tp->ucopy.memory += skb->truesize;
|
|
|
|
if (tp->ucopy.memory > sk->sk_rcvbuf) {
|
|
|
|
struct sk_buff *skb1;
|
|
|
|
|
|
|
|
BUG_ON(sock_owned_by_user(sk));
|
|
|
|
|
|
|
|
while ((skb1 = __skb_dequeue(&tp->ucopy.prequeue)) != NULL) {
|
|
|
|
sk->sk_backlog_rcv(sk, skb1);
|
|
|
|
NET_INC_STATS_BH(LINUX_MIB_TCPPREQUEUEDROPPED);
|
|
|
|
}
|
|
|
|
|
|
|
|
tp->ucopy.memory = 0;
|
|
|
|
} else if (skb_queue_len(&tp->ucopy.prequeue) == 1) {
|
|
|
|
wake_up_interruptible(sk->sk_sleep);
|
|
|
|
if (!tcp_ack_scheduled(tp))
|
|
|
|
tcp_reset_xmit_timer(sk, TCP_TIME_DACK, (3*TCP_RTO_MIN)/4);
|
|
|
|
}
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
#undef STATE_TRACE
|
|
|
|
|
|
|
|
#ifdef STATE_TRACE
|
|
|
|
static const char *statename[]={
|
|
|
|
"Unused","Established","Syn Sent","Syn Recv",
|
|
|
|
"Fin Wait 1","Fin Wait 2","Time Wait", "Close",
|
|
|
|
"Close Wait","Last ACK","Listen","Closing"
|
|
|
|
};
|
|
|
|
#endif
|
|
|
|
|
|
|
|
static __inline__ void tcp_set_state(struct sock *sk, int state)
|
|
|
|
{
|
|
|
|
int oldstate = sk->sk_state;
|
|
|
|
|
|
|
|
switch (state) {
|
|
|
|
case TCP_ESTABLISHED:
|
|
|
|
if (oldstate != TCP_ESTABLISHED)
|
|
|
|
TCP_INC_STATS(TCP_MIB_CURRESTAB);
|
|
|
|
break;
|
|
|
|
|
|
|
|
case TCP_CLOSE:
|
|
|
|
if (oldstate == TCP_CLOSE_WAIT || oldstate == TCP_ESTABLISHED)
|
|
|
|
TCP_INC_STATS(TCP_MIB_ESTABRESETS);
|
|
|
|
|
|
|
|
sk->sk_prot->unhash(sk);
|
|
|
|
if (tcp_sk(sk)->bind_hash &&
|
|
|
|
!(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
|
|
|
|
tcp_put_port(sk);
|
|
|
|
/* fall through */
|
|
|
|
default:
|
|
|
|
if (oldstate==TCP_ESTABLISHED)
|
|
|
|
TCP_DEC_STATS(TCP_MIB_CURRESTAB);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Change state AFTER socket is unhashed to avoid closed
|
|
|
|
* socket sitting in hash tables.
|
|
|
|
*/
|
|
|
|
sk->sk_state = state;
|
|
|
|
|
|
|
|
#ifdef STATE_TRACE
|
|
|
|
SOCK_DEBUG(sk, "TCP sk=%p, State %s -> %s\n",sk, statename[oldstate],statename[state]);
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ void tcp_done(struct sock *sk)
|
|
|
|
{
|
|
|
|
tcp_set_state(sk, TCP_CLOSE);
|
|
|
|
tcp_clear_xmit_timers(sk);
|
|
|
|
|
|
|
|
sk->sk_shutdown = SHUTDOWN_MASK;
|
|
|
|
|
|
|
|
if (!sock_flag(sk, SOCK_DEAD))
|
|
|
|
sk->sk_state_change(sk);
|
|
|
|
else
|
|
|
|
tcp_destroy_sock(sk);
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ void tcp_sack_reset(struct tcp_options_received *rx_opt)
|
|
|
|
{
|
|
|
|
rx_opt->dsack = 0;
|
|
|
|
rx_opt->eff_sacks = 0;
|
|
|
|
rx_opt->num_sacks = 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static __inline__ void tcp_build_and_update_options(__u32 *ptr, struct tcp_sock *tp, __u32 tstamp)
|
|
|
|
{
|
|
|
|
if (tp->rx_opt.tstamp_ok) {
|
|
|
|
*ptr++ = __constant_htonl((TCPOPT_NOP << 24) |
|
|
|
|
(TCPOPT_NOP << 16) |
|
|
|
|
(TCPOPT_TIMESTAMP << 8) |
|
|
|
|
TCPOLEN_TIMESTAMP);
|
|
|
|
*ptr++ = htonl(tstamp);
|
|
|
|
*ptr++ = htonl(tp->rx_opt.ts_recent);
|
|
|
|
}
|
|
|
|
if (tp->rx_opt.eff_sacks) {
|
|
|
|
struct tcp_sack_block *sp = tp->rx_opt.dsack ? tp->duplicate_sack : tp->selective_acks;
|
|
|
|
int this_sack;
|
|
|
|
|
|
|
|
*ptr++ = __constant_htonl((TCPOPT_NOP << 24) |
|
|
|
|
(TCPOPT_NOP << 16) |
|
|
|
|
(TCPOPT_SACK << 8) |
|
|
|
|
(TCPOLEN_SACK_BASE +
|
|
|
|
(tp->rx_opt.eff_sacks * TCPOLEN_SACK_PERBLOCK)));
|
|
|
|
for(this_sack = 0; this_sack < tp->rx_opt.eff_sacks; this_sack++) {
|
|
|
|
*ptr++ = htonl(sp[this_sack].start_seq);
|
|
|
|
*ptr++ = htonl(sp[this_sack].end_seq);
|
|
|
|
}
|
|
|
|
if (tp->rx_opt.dsack) {
|
|
|
|
tp->rx_opt.dsack = 0;
|
|
|
|
tp->rx_opt.eff_sacks--;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Construct a tcp options header for a SYN or SYN_ACK packet.
|
|
|
|
* If this is every changed make sure to change the definition of
|
|
|
|
* MAX_SYN_SIZE to match the new maximum number of options that you
|
|
|
|
* can generate.
|
|
|
|
*/
|
|
|
|
static inline void tcp_syn_build_options(__u32 *ptr, int mss, int ts, int sack,
|
|
|
|
int offer_wscale, int wscale, __u32 tstamp, __u32 ts_recent)
|
|
|
|
{
|
|
|
|
/* We always get an MSS option.
|
|
|
|
* The option bytes which will be seen in normal data
|
|
|
|
* packets should timestamps be used, must be in the MSS
|
|
|
|
* advertised. But we subtract them from tp->mss_cache so
|
|
|
|
* that calculations in tcp_sendmsg are simpler etc.
|
|
|
|
* So account for this fact here if necessary. If we
|
|
|
|
* don't do this correctly, as a receiver we won't
|
|
|
|
* recognize data packets as being full sized when we
|
|
|
|
* should, and thus we won't abide by the delayed ACK
|
|
|
|
* rules correctly.
|
|
|
|
* SACKs don't matter, we never delay an ACK when we
|
|
|
|
* have any of those going out.
|
|
|
|
*/
|
|
|
|
*ptr++ = htonl((TCPOPT_MSS << 24) | (TCPOLEN_MSS << 16) | mss);
|
|
|
|
if (ts) {
|
|
|
|
if(sack)
|
|
|
|
*ptr++ = __constant_htonl((TCPOPT_SACK_PERM << 24) | (TCPOLEN_SACK_PERM << 16) |
|
|
|
|
(TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
|
|
|
|
else
|
|
|
|
*ptr++ = __constant_htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
|
|
|
|
(TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP);
|
|
|
|
*ptr++ = htonl(tstamp); /* TSVAL */
|
|
|
|
*ptr++ = htonl(ts_recent); /* TSECR */
|
|
|
|
} else if(sack)
|
|
|
|
*ptr++ = __constant_htonl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) |
|
|
|
|
(TCPOPT_SACK_PERM << 8) | TCPOLEN_SACK_PERM);
|
|
|
|
if (offer_wscale)
|
|
|
|
*ptr++ = htonl((TCPOPT_NOP << 24) | (TCPOPT_WINDOW << 16) | (TCPOLEN_WINDOW << 8) | (wscale));
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Determine a window scaling and initial window to offer. */
|
|
|
|
extern void tcp_select_initial_window(int __space, __u32 mss,
|
|
|
|
__u32 *rcv_wnd, __u32 *window_clamp,
|
|
|
|
int wscale_ok, __u8 *rcv_wscale);
|
|
|
|
|
|
|
|
static inline int tcp_win_from_space(int space)
|
|
|
|
{
|
|
|
|
return sysctl_tcp_adv_win_scale<=0 ?
|
|
|
|
(space>>(-sysctl_tcp_adv_win_scale)) :
|
|
|
|
space - (space>>sysctl_tcp_adv_win_scale);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* Note: caller must be prepared to deal with negative returns */
|
|
|
|
static inline int tcp_space(const struct sock *sk)
|
|
|
|
{
|
|
|
|
return tcp_win_from_space(sk->sk_rcvbuf -
|
|
|
|
atomic_read(&sk->sk_rmem_alloc));
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int tcp_full_space(const struct sock *sk)
|
|
|
|
{
|
|
|
|
return tcp_win_from_space(sk->sk_rcvbuf);
|
|
|
|
}
|
|
|
|
|
2005-06-19 07:47:21 +02:00
|
|
|
static inline void tcp_acceptq_queue(struct sock *sk, struct request_sock *req,
|
2005-04-17 00:20:36 +02:00
|
|
|
struct sock *child)
|
|
|
|
{
|
2005-06-19 07:47:59 +02:00
|
|
|
reqsk_queue_add(&tcp_sk(sk)->accept_queue, req, sk, child);
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline void
|
2005-06-19 07:47:21 +02:00
|
|
|
tcp_synq_removed(struct sock *sk, struct request_sock *req)
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
2005-06-19 07:47:59 +02:00
|
|
|
if (reqsk_queue_removed(&tcp_sk(sk)->accept_queue, req) == 0)
|
2005-04-17 00:20:36 +02:00
|
|
|
tcp_delete_keepalive_timer(sk);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void tcp_synq_added(struct sock *sk)
|
|
|
|
{
|
2005-06-19 07:47:59 +02:00
|
|
|
if (reqsk_queue_added(&tcp_sk(sk)->accept_queue) == 0)
|
2005-04-17 00:20:36 +02:00
|
|
|
tcp_reset_keepalive_timer(sk, TCP_TIMEOUT_INIT);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int tcp_synq_len(struct sock *sk)
|
|
|
|
{
|
2005-06-19 07:47:59 +02:00
|
|
|
return reqsk_queue_len(&tcp_sk(sk)->accept_queue);
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline int tcp_synq_young(struct sock *sk)
|
|
|
|
{
|
2005-06-19 07:47:59 +02:00
|
|
|
return reqsk_queue_len_young(&tcp_sk(sk)->accept_queue);
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
static inline int tcp_synq_is_full(struct sock *sk)
|
|
|
|
{
|
2005-06-19 07:47:59 +02:00
|
|
|
return reqsk_queue_is_full(&tcp_sk(sk)->accept_queue);
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
|
2005-06-19 07:47:21 +02:00
|
|
|
static inline void tcp_synq_unlink(struct tcp_sock *tp, struct request_sock *req,
|
2005-06-19 07:47:59 +02:00
|
|
|
struct request_sock **prev)
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
2005-06-19 07:47:59 +02:00
|
|
|
reqsk_queue_unlink(&tp->accept_queue, req, prev);
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
|
2005-06-19 07:47:21 +02:00
|
|
|
static inline void tcp_synq_drop(struct sock *sk, struct request_sock *req,
|
|
|
|
struct request_sock **prev)
|
2005-04-17 00:20:36 +02:00
|
|
|
{
|
|
|
|
tcp_synq_unlink(tcp_sk(sk), req, prev);
|
|
|
|
tcp_synq_removed(sk, req);
|
2005-06-19 07:47:21 +02:00
|
|
|
reqsk_free(req);
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
|
2005-06-19 07:47:21 +02:00
|
|
|
static __inline__ void tcp_openreq_init(struct request_sock *req,
|
2005-04-17 00:20:36 +02:00
|
|
|
struct tcp_options_received *rx_opt,
|
|
|
|
struct sk_buff *skb)
|
|
|
|
{
|
[NET] Generalise TCP's struct open_request minisock infrastructure
Kept this first changeset minimal, without changing existing names to
ease peer review.
Basicaly tcp_openreq_alloc now receives the or_calltable, that in turn
has two new members:
->slab, that replaces tcp_openreq_cachep
->obj_size, to inform the size of the openreq descendant for
a specific protocol
The protocol specific fields in struct open_request were moved to a
class hierarchy, with the things that are common to all connection
oriented PF_INET protocols in struct inet_request_sock, the TCP ones
in tcp_request_sock, that is an inet_request_sock, that is an
open_request.
I.e. this uses the same approach used for the struct sock class
hierarchy, with sk_prot indicating if the protocol wants to use the
open_request infrastructure by filling in sk_prot->rsk_prot with an
or_calltable.
Results? Performance is improved and TCP v4 now uses only 64 bytes per
open request minisock, down from 96 without this patch :-)
Next changeset will rename some of the structs, fields and functions
mentioned above, struct or_calltable is way unclear, better name it
struct request_sock_ops, s/struct open_request/struct request_sock/g,
etc.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-19 07:46:52 +02:00
|
|
|
struct inet_request_sock *ireq = inet_rsk(req);
|
|
|
|
|
2005-04-17 00:20:36 +02:00
|
|
|
req->rcv_wnd = 0; /* So that tcp_send_synack() knows! */
|
[NET] Generalise TCP's struct open_request minisock infrastructure
Kept this first changeset minimal, without changing existing names to
ease peer review.
Basicaly tcp_openreq_alloc now receives the or_calltable, that in turn
has two new members:
->slab, that replaces tcp_openreq_cachep
->obj_size, to inform the size of the openreq descendant for
a specific protocol
The protocol specific fields in struct open_request were moved to a
class hierarchy, with the things that are common to all connection
oriented PF_INET protocols in struct inet_request_sock, the TCP ones
in tcp_request_sock, that is an inet_request_sock, that is an
open_request.
I.e. this uses the same approach used for the struct sock class
hierarchy, with sk_prot indicating if the protocol wants to use the
open_request infrastructure by filling in sk_prot->rsk_prot with an
or_calltable.
Results? Performance is improved and TCP v4 now uses only 64 bytes per
open request minisock, down from 96 without this patch :-)
Next changeset will rename some of the structs, fields and functions
mentioned above, struct or_calltable is way unclear, better name it
struct request_sock_ops, s/struct open_request/struct request_sock/g,
etc.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-19 07:46:52 +02:00
|
|
|
tcp_rsk(req)->rcv_isn = TCP_SKB_CB(skb)->seq;
|
2005-04-17 00:20:36 +02:00
|
|
|
req->mss = rx_opt->mss_clamp;
|
|
|
|
req->ts_recent = rx_opt->saw_tstamp ? rx_opt->rcv_tsval : 0;
|
[NET] Generalise TCP's struct open_request minisock infrastructure
Kept this first changeset minimal, without changing existing names to
ease peer review.
Basicaly tcp_openreq_alloc now receives the or_calltable, that in turn
has two new members:
->slab, that replaces tcp_openreq_cachep
->obj_size, to inform the size of the openreq descendant for
a specific protocol
The protocol specific fields in struct open_request were moved to a
class hierarchy, with the things that are common to all connection
oriented PF_INET protocols in struct inet_request_sock, the TCP ones
in tcp_request_sock, that is an inet_request_sock, that is an
open_request.
I.e. this uses the same approach used for the struct sock class
hierarchy, with sk_prot indicating if the protocol wants to use the
open_request infrastructure by filling in sk_prot->rsk_prot with an
or_calltable.
Results? Performance is improved and TCP v4 now uses only 64 bytes per
open request minisock, down from 96 without this patch :-)
Next changeset will rename some of the structs, fields and functions
mentioned above, struct or_calltable is way unclear, better name it
struct request_sock_ops, s/struct open_request/struct request_sock/g,
etc.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-06-19 07:46:52 +02:00
|
|
|
ireq->tstamp_ok = rx_opt->tstamp_ok;
|
|
|
|
ireq->sack_ok = rx_opt->sack_ok;
|
|
|
|
ireq->snd_wscale = rx_opt->snd_wscale;
|
|
|
|
ireq->wscale_ok = rx_opt->wscale_ok;
|
|
|
|
ireq->acked = 0;
|
|
|
|
ireq->ecn_ok = 0;
|
|
|
|
ireq->rmt_port = skb->h.th->source;
|
2005-04-17 00:20:36 +02:00
|
|
|
}
|
|
|
|
|
|
|
|
extern void tcp_enter_memory_pressure(void);
|
|
|
|
|
|
|
|
extern void tcp_listen_wlock(void);
|
|
|
|
|
|
|
|
/* - We may sleep inside this lock.
|
|
|
|
* - If sleeping is not required (or called from BH),
|
|
|
|
* use plain read_(un)lock(&tcp_lhash_lock).
|
|
|
|
*/
|
|
|
|
|
|
|
|
static inline void tcp_listen_lock(void)
|
|
|
|
{
|
|
|
|
/* read_lock synchronizes to candidates to writers */
|
|
|
|
read_lock(&tcp_lhash_lock);
|
|
|
|
atomic_inc(&tcp_lhash_users);
|
|
|
|
read_unlock(&tcp_lhash_lock);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void tcp_listen_unlock(void)
|
|
|
|
{
|
|
|
|
if (atomic_dec_and_test(&tcp_lhash_users))
|
|
|
|
wake_up(&tcp_lhash_wait);
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int keepalive_intvl_when(const struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
return tp->keepalive_intvl ? : sysctl_tcp_keepalive_intvl;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int keepalive_time_when(const struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
return tp->keepalive_time ? : sysctl_tcp_keepalive_time;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int tcp_fin_time(const struct tcp_sock *tp)
|
|
|
|
{
|
|
|
|
int fin_timeout = tp->linger2 ? : sysctl_tcp_fin_timeout;
|
|
|
|
|
|
|
|
if (fin_timeout < (tp->rto<<2) - (tp->rto>>1))
|
|
|
|
fin_timeout = (tp->rto<<2) - (tp->rto>>1);
|
|
|
|
|
|
|
|
return fin_timeout;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int tcp_paws_check(const struct tcp_options_received *rx_opt, int rst)
|
|
|
|
{
|
|
|
|
if ((s32)(rx_opt->rcv_tsval - rx_opt->ts_recent) >= 0)
|
|
|
|
return 0;
|
|
|
|
if (xtime.tv_sec >= rx_opt->ts_recent_stamp + TCP_PAWS_24DAYS)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
/* RST segments are not recommended to carry timestamp,
|
|
|
|
and, if they do, it is recommended to ignore PAWS because
|
|
|
|
"their cleanup function should take precedence over timestamps."
|
|
|
|
Certainly, it is mistake. It is necessary to understand the reasons
|
|
|
|
of this constraint to relax it: if peer reboots, clock may go
|
|
|
|
out-of-sync and half-open connections will not be reset.
|
|
|
|
Actually, the problem would be not existing if all
|
|
|
|
the implementations followed draft about maintaining clock
|
|
|
|
via reboots. Linux-2.2 DOES NOT!
|
|
|
|
|
|
|
|
However, we can relax time bounds for RST segments to MSL.
|
|
|
|
*/
|
|
|
|
if (rst && xtime.tv_sec >= rx_opt->ts_recent_stamp + TCP_PAWS_MSL)
|
|
|
|
return 0;
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void tcp_v4_setup_caps(struct sock *sk, struct dst_entry *dst)
|
|
|
|
{
|
|
|
|
sk->sk_route_caps = dst->dev->features;
|
|
|
|
if (sk->sk_route_caps & NETIF_F_TSO) {
|
|
|
|
if (sock_flag(sk, SOCK_NO_LARGESEND) || dst->header_len)
|
|
|
|
sk->sk_route_caps &= ~NETIF_F_TSO;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#define TCP_CHECK_TIMER(sk) do { } while (0)
|
|
|
|
|
|
|
|
static inline int tcp_use_frto(const struct sock *sk)
|
|
|
|
{
|
|
|
|
const struct tcp_sock *tp = tcp_sk(sk);
|
|
|
|
|
|
|
|
/* F-RTO must be activated in sysctl and there must be some
|
|
|
|
* unsent new data, and the advertised window should allow
|
|
|
|
* sending it.
|
|
|
|
*/
|
|
|
|
return (sysctl_tcp_frto && sk->sk_send_head &&
|
|
|
|
!after(TCP_SKB_CB(sk->sk_send_head)->end_seq,
|
|
|
|
tp->snd_una + tp->snd_wnd));
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline void tcp_mib_init(void)
|
|
|
|
{
|
|
|
|
/* See RFC 2012 */
|
|
|
|
TCP_ADD_STATS_USER(TCP_MIB_RTOALGORITHM, 1);
|
|
|
|
TCP_ADD_STATS_USER(TCP_MIB_RTOMIN, TCP_RTO_MIN*1000/HZ);
|
|
|
|
TCP_ADD_STATS_USER(TCP_MIB_RTOMAX, TCP_RTO_MAX*1000/HZ);
|
|
|
|
TCP_ADD_STATS_USER(TCP_MIB_MAXCONN, -1);
|
|
|
|
}
|
|
|
|
|
|
|
|
/* /proc */
|
|
|
|
enum tcp_seq_states {
|
|
|
|
TCP_SEQ_STATE_LISTENING,
|
|
|
|
TCP_SEQ_STATE_OPENREQ,
|
|
|
|
TCP_SEQ_STATE_ESTABLISHED,
|
|
|
|
TCP_SEQ_STATE_TIME_WAIT,
|
|
|
|
};
|
|
|
|
|
|
|
|
struct tcp_seq_afinfo {
|
|
|
|
struct module *owner;
|
|
|
|
char *name;
|
|
|
|
sa_family_t family;
|
|
|
|
int (*seq_show) (struct seq_file *m, void *v);
|
|
|
|
struct file_operations *seq_fops;
|
|
|
|
};
|
|
|
|
|
|
|
|
struct tcp_iter_state {
|
|
|
|
sa_family_t family;
|
|
|
|
enum tcp_seq_states state;
|
|
|
|
struct sock *syn_wait_sk;
|
|
|
|
int bucket, sbucket, num, uid;
|
|
|
|
struct seq_operations seq_ops;
|
|
|
|
};
|
|
|
|
|
|
|
|
extern int tcp_proc_register(struct tcp_seq_afinfo *afinfo);
|
|
|
|
extern void tcp_proc_unregister(struct tcp_seq_afinfo *afinfo);
|
|
|
|
|
|
|
|
#endif /* _TCP_H */
|