1 /* SCTP kernel reference Implementation
2 * Copyright (c) 1999-2000 Cisco, Inc.
3 * Copyright (c) 1999-2001 Motorola, Inc.
4 * Copyright (c) 2002 International Business Machines, Corp.
6 * This file is part of the SCTP kernel reference Implementation
8 * These functions are the methods for accessing the SCTP inqueue.
10 * An SCTP inqueue is a queue into which you push SCTP packets
11 * (which might be bundles or fragments of chunks) and out of which you
12 * pop SCTP whole chunks.
14 * The SCTP reference implementation is free software;
15 * you can redistribute it and/or modify it under the terms of
16 * the GNU General Public License as published by
17 * the Free Software Foundation; either version 2, or (at your option)
20 * The SCTP reference implementation is distributed in the hope that it
21 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
22 * ************************
23 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
24 * See the GNU General Public License for more details.
26 * You should have received a copy of the GNU General Public License
27 * along with GNU CC; see the file COPYING. If not, write to
28 * the Free Software Foundation, 59 Temple Place - Suite 330,
29 * Boston, MA 02111-1307, USA.
31 * Please send any bug reports or fixes you make to the
33 * lksctp developers <lksctp-developers@lists.sourceforge.net>
35 * Or submit a bug report through the following website:
36 * http://www.sf.net/projects/lksctp
38 * Written or modified by:
39 * La Monte H.P. Yarroll <piggy@acm.org>
40 * Karl Knutson <karl@athena.chicago.il.us>
42 * Any bugs reported given to us we will try to fix... any fixes shared will
43 * be incorporated into the next SCTP release.
46 #include <net/sctp/sctp.h>
47 #include <net/sctp/sm.h>
48 #include <linux/interrupt.h>
50 /* Initialize an SCTP inqueue. */
51 void sctp_inq_init(struct sctp_inq *queue)
53 skb_queue_head_init(&queue->in);
54 queue->in_progress = NULL;
56 /* Create a task for delivering data. */
57 INIT_WORK(&queue->immediate, NULL, NULL);
62 /* Create an initialized sctp_inq. */
63 struct sctp_inq *sctp_inq_new(void)
65 struct sctp_inq *retval;
67 retval = t_new(struct sctp_inq, GFP_ATOMIC);
69 sctp_inq_init(retval);
75 /* Release the memory associated with an SCTP inqueue. */
76 void sctp_inq_free(struct sctp_inq *queue)
78 struct sctp_chunk *chunk;
80 /* Empty the queue. */
81 while ((chunk = (struct sctp_chunk *) skb_dequeue(&queue->in)))
82 sctp_chunk_free(chunk);
84 /* If there is a packet which is currently being worked on,
87 if (queue->in_progress)
88 sctp_chunk_free(queue->in_progress);
90 if (queue->malloced) {
91 /* Dump the master memory segment. */
96 /* Put a new packet in an SCTP inqueue.
97 * We assume that packet->sctp_hdr is set and in host byte order.
99 void sctp_inq_push(struct sctp_inq *q, struct sctp_chunk *packet)
101 /* Directly call the packet handling routine. */
103 /* We are now calling this either from the soft interrupt
104 * or from the backlog processing.
105 * Eventually, we should clean up inqueue to not rely
106 * on the BH related data structures.
108 skb_queue_tail(&(q->in), (struct sk_buff *) packet);
109 q->immediate.func(q->immediate.data);
112 /* Extract a chunk from an SCTP inqueue.
114 * WARNING: If you need to put the chunk on another queue, you need to
115 * make a shallow copy (clone) of it.
117 struct sctp_chunk *sctp_inq_pop(struct sctp_inq *queue)
119 struct sctp_chunk *chunk;
120 sctp_chunkhdr_t *ch = NULL;
122 /* The assumption is that we are safe to process the chunks
126 if ((chunk = queue->in_progress)) {
127 /* There is a packet that we have been working on.
128 * Any post processing work to do before we move on?
130 if (chunk->singleton ||
131 chunk->end_of_packet ||
133 sctp_chunk_free(chunk);
134 chunk = queue->in_progress = NULL;
136 /* Nothing to do. Next chunk in the packet, please. */
137 ch = (sctp_chunkhdr_t *) chunk->chunk_end;
139 /* Force chunk->skb->data to chunk->chunk_end. */
141 chunk->chunk_end - chunk->skb->data);
145 /* Do we need to take the next packet out of the queue to process? */
147 /* Is the queue empty? */
148 if (skb_queue_empty(&queue->in))
151 chunk = queue->in_progress =
152 (struct sctp_chunk *) skb_dequeue(&queue->in);
154 /* This is the first chunk in the packet. */
155 chunk->singleton = 1;
156 ch = (sctp_chunkhdr_t *) chunk->skb->data;
159 chunk->chunk_hdr = ch;
160 chunk->chunk_end = ((__u8 *) ch)
161 + WORD_ROUND(ntohs(ch->length));
162 skb_pull(chunk->skb, sizeof(sctp_chunkhdr_t));
163 chunk->subh.v = NULL; /* Subheader is no longer valid. */
165 if (chunk->chunk_end < chunk->skb->tail) {
166 /* This is not a singleton */
167 chunk->singleton = 0;
169 /* We are at the end of the packet, so mark the chunk
170 * in case we need to send a SACK.
172 chunk->end_of_packet = 1;
175 SCTP_DEBUG_PRINTK("+++sctp_inq_pop+++ chunk %p[%s],"
176 " length %d, skb->len %d\n",chunk,
177 sctp_cname(SCTP_ST_CHUNK(chunk->chunk_hdr->type)),
178 ntohs(chunk->chunk_hdr->length), chunk->skb->len);
182 /* Set a top-half handler.
184 * Originally, we the top-half handler was scheduled as a BH. We now
185 * call the handler directly in sctp_inq_push() at a time that
186 * we know we are lock safe.
187 * The intent is that this routine will pull stuff out of the
188 * inqueue and process it.
190 void sctp_inq_set_th_handler(struct sctp_inq *q,
191 void (*callback)(void *), void *arg)
193 INIT_WORK(&q->immediate, callback, arg);