cpuacct: reduce one NULL check in fast-path
[linux-2.6/verdex.git] / net / sctp / primitive.c
blob8cb4f060bce68298d2f3d59ff67bf97fab276dbc
1 /* SCTP kernel implementation
2 * Copyright (c) 1999-2000 Cisco, Inc.
3 * Copyright (c) 1999-2001 Motorola, Inc.
5 * This file is part of the SCTP kernel implementation
7 * These functions implement the SCTP primitive functions from Section 10.
9 * Note that the descriptions from the specification are USER level
10 * functions--this file is the functions which populate the struct proto
11 * for SCTP which is the BOTTOM of the sockets interface.
13 * This SCTP implementation is free software;
14 * you can redistribute it and/or modify it under the terms of
15 * the GNU General Public License as published by
16 * the Free Software Foundation; either version 2, or (at your option)
17 * any later version.
19 * This SCTP implementation is distributed in the hope that it
20 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
21 * ************************
22 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
23 * See the GNU General Public License for more details.
25 * You should have received a copy of the GNU General Public License
26 * along with GNU CC; see the file COPYING. If not, write to
27 * the Free Software Foundation, 59 Temple Place - Suite 330,
28 * Boston, MA 02111-1307, USA.
30 * Please send any bug reports or fixes you make to the
31 * email address(es):
32 * lksctp developers <lksctp-developers@lists.sourceforge.net>
34 * Or submit a bug report through the following website:
35 * http://www.sf.net/projects/lksctp
37 * Written or modified by:
38 * La Monte H.P. Yarroll <piggy@acm.org>
39 * Narasimha Budihal <narasimha@refcode.org>
40 * Karl Knutson <karl@athena.chicago.il.us>
41 * Ardelle Fan <ardelle.fan@intel.com>
42 * Kevin Gao <kevin.gao@intel.com>
44 * Any bugs reported given to us we will try to fix... any fixes shared will
45 * be incorporated into the next SCTP release.
48 #include <linux/types.h>
49 #include <linux/list.h> /* For struct list_head */
50 #include <linux/socket.h>
51 #include <linux/ip.h>
52 #include <linux/time.h> /* For struct timeval */
53 #include <net/sock.h>
54 #include <net/sctp/sctp.h>
55 #include <net/sctp/sm.h>
57 #define DECLARE_PRIMITIVE(name) \
58 /* This is called in the code as sctp_primitive_ ## name. */ \
59 int sctp_primitive_ ## name(struct sctp_association *asoc, \
60 void *arg) { \
61 int error = 0; \
62 sctp_event_t event_type; sctp_subtype_t subtype; \
63 sctp_state_t state; \
64 struct sctp_endpoint *ep; \
66 event_type = SCTP_EVENT_T_PRIMITIVE; \
67 subtype = SCTP_ST_PRIMITIVE(SCTP_PRIMITIVE_ ## name); \
68 state = asoc ? asoc->state : SCTP_STATE_CLOSED; \
69 ep = asoc ? asoc->ep : NULL; \
71 error = sctp_do_sm(event_type, subtype, state, ep, asoc, \
72 arg, GFP_KERNEL); \
73 return error; \
76 /* 10.1 ULP-to-SCTP
77 * B) Associate
79 * Format: ASSOCIATE(local SCTP instance name, destination transport addr,
80 * outbound stream count)
81 * -> association id [,destination transport addr list] [,outbound stream
82 * count]
84 * This primitive allows the upper layer to initiate an association to a
85 * specific peer endpoint.
87 * This version assumes that asoc is fully populated with the initial
88 * parameters. We then return a traditional kernel indicator of
89 * success or failure.
92 /* This is called in the code as sctp_primitive_ASSOCIATE. */
94 DECLARE_PRIMITIVE(ASSOCIATE)
96 /* 10.1 ULP-to-SCTP
97 * C) Shutdown
99 * Format: SHUTDOWN(association id)
100 * -> result
102 * Gracefully closes an association. Any locally queued user data
103 * will be delivered to the peer. The association will be terminated only
104 * after the peer acknowledges all the SCTP packets sent. A success code
105 * will be returned on successful termination of the association. If
106 * attempting to terminate the association results in a failure, an error
107 * code shall be returned.
110 DECLARE_PRIMITIVE(SHUTDOWN);
112 /* 10.1 ULP-to-SCTP
113 * C) Abort
115 * Format: Abort(association id [, cause code])
116 * -> result
118 * Ungracefully closes an association. Any locally queued user data
119 * will be discarded and an ABORT chunk is sent to the peer. A success
120 * code will be returned on successful abortion of the association. If
121 * attempting to abort the association results in a failure, an error
122 * code shall be returned.
125 DECLARE_PRIMITIVE(ABORT);
127 /* 10.1 ULP-to-SCTP
128 * E) Send
130 * Format: SEND(association id, buffer address, byte count [,context]
131 * [,stream id] [,life time] [,destination transport address]
132 * [,unorder flag] [,no-bundle flag] [,payload protocol-id] )
133 * -> result
135 * This is the main method to send user data via SCTP.
137 * Mandatory attributes:
139 * o association id - local handle to the SCTP association
141 * o buffer address - the location where the user message to be
142 * transmitted is stored;
144 * o byte count - The size of the user data in number of bytes;
146 * Optional attributes:
148 * o context - an optional 32 bit integer that will be carried in the
149 * sending failure notification to the ULP if the transportation of
150 * this User Message fails.
152 * o stream id - to indicate which stream to send the data on. If not
153 * specified, stream 0 will be used.
155 * o life time - specifies the life time of the user data. The user data
156 * will not be sent by SCTP after the life time expires. This
157 * parameter can be used to avoid efforts to transmit stale
158 * user messages. SCTP notifies the ULP if the data cannot be
159 * initiated to transport (i.e. sent to the destination via SCTP's
160 * send primitive) within the life time variable. However, the
161 * user data will be transmitted if SCTP has attempted to transmit a
162 * chunk before the life time expired.
164 * o destination transport address - specified as one of the destination
165 * transport addresses of the peer endpoint to which this packet
166 * should be sent. Whenever possible, SCTP should use this destination
167 * transport address for sending the packets, instead of the current
168 * primary path.
170 * o unorder flag - this flag, if present, indicates that the user
171 * would like the data delivered in an unordered fashion to the peer
172 * (i.e., the U flag is set to 1 on all DATA chunks carrying this
173 * message).
175 * o no-bundle flag - instructs SCTP not to bundle this user data with
176 * other outbound DATA chunks. SCTP MAY still bundle even when
177 * this flag is present, when faced with network congestion.
179 * o payload protocol-id - A 32 bit unsigned integer that is to be
180 * passed to the peer indicating the type of payload protocol data
181 * being transmitted. This value is passed as opaque data by SCTP.
184 DECLARE_PRIMITIVE(SEND);
186 /* 10.1 ULP-to-SCTP
187 * J) Request Heartbeat
189 * Format: REQUESTHEARTBEAT(association id, destination transport address)
191 * -> result
193 * Instructs the local endpoint to perform a HeartBeat on the specified
194 * destination transport address of the given association. The returned
195 * result should indicate whether the transmission of the HEARTBEAT
196 * chunk to the destination address is successful.
198 * Mandatory attributes:
200 * o association id - local handle to the SCTP association
202 * o destination transport address - the transport address of the
203 * association on which a heartbeat should be issued.
206 DECLARE_PRIMITIVE(REQUESTHEARTBEAT);
208 /* ADDIP
209 * 3.1.1 Address Configuration Change Chunk (ASCONF)
211 * This chunk is used to communicate to the remote endpoint one of the
212 * configuration change requests that MUST be acknowledged. The
213 * information carried in the ASCONF Chunk uses the form of a
214 * Type-Length-Value (TLV), as described in "3.2.1 Optional/
215 * Variable-length Parameter Format" in RFC2960 [5], forall variable
216 * parameters.
219 DECLARE_PRIMITIVE(ASCONF);