[apple/xnu.git] / bsd / netccitt / hd_output.c

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*
 * Copyright (c) University of British Columbia, 1984
 * Copyright (c) 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Laboratory for Computation Vision and the Computer Science Department
 * of the University of British Columbia.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)hd_output.c	8.1 (Berkeley) 6/10/93
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/domain.h>
#include <sys/socket.h>
#include <sys/syslog.h>
#include <sys/protosw.h>
#include <sys/errno.h>
#include <sys/time.h>
#include <sys/kernel.h>

#include <net/if.h>

#include <netccitt/hdlc.h>
#include <netccitt/hd_var.h>
#include <netccitt/x25.h>

/*
 *      HDLC OUTPUT INTERFACE
 *
 *      This routine is called when the X.25 packet layer output routine
 *      has a information frame (iframe)  to write.   It is  also called 
 *      by the input and control routines of the HDLC layer.
 */

hd_output (hdp, m0)
register struct hdcb *hdp;
struct mbuf *m0;
{
	struct x25config *xcp;
	register struct mbuf *m = m0;
	int len;

	if (m == NULL)
		panic ("hd_output");
	if ((m->m_flags & M_PKTHDR) == 0)
		panic ("hd_output 2");

	if (hdp->hd_state != ABM) {
		m_freem (m);
		return;
	}

	/*
	 * Make room for the hdlc header either by prepending
	 * another mbuf, or by adjusting the offset and length
	 * of the first mbuf in the mbuf chain.
	 */

	M_PREPEND(m, HDHEADERLN, M_DONTWAIT);
	if (m == NULL)
		return;
	for (len = 0; m; m = m->m_next)
		len += m->m_len;
	m = m0;
	m->m_pkthdr.len = len;

	hd_append (&hdp->hd_txq, m);
	hd_start (hdp);
}

hd_start (hdp)
register struct hdcb *hdp;
{
	register struct mbuf *m;

	/* 
	 * The iframe is only transmitted if all these conditions are FALSE.
	 * The iframe remains queued (hdp->hd_txq) however and will be
	 * transmitted as soon as these conditions are cleared.
	 */

	while (!(hdp->hd_condition & (TIMER_RECOVERY_CONDITION | REMOTE_RNR_CONDITION | REJ_CONDITION))) {
		if (hdp->hd_vs == (hdp->hd_lastrxnr + hdp->hd_xcp->xc_lwsize) % MODULUS) {

			/* We have now exceeded the  maximum  number  of 
			   outstanding iframes. Therefore,  we must wait 
			   until  at least  one is acknowledged if this 
			   condition  is not  turned off before we are
			   requested to write another iframe. */
			hdp->hd_window_condition++;
			break;
		}

		/* hd_remove top iframe from transmit queue. */
		if ((m = hd_remove (&hdp->hd_txq)) == NULL)
			break;

		hd_send_iframe (hdp, m, POLLOFF);
	}
}

/* 
 *  This procedure is passed a buffer descriptor for an iframe. It builds
 *  the rest of the control part of the frame and then writes it out.  It
 *  also  starts the  acknowledgement  timer and keeps  the iframe in the
 *  Retransmit queue (Retxq) just in case  we have to do this again.
 *
 *  Note: This routine is also called from hd_input.c when retransmission
 *       of old frames is required.
 */

hd_send_iframe (hdp, buf, poll_bit)
register struct hdcb *hdp;
register struct mbuf *buf;
int poll_bit;
{
	register struct Hdlc_iframe *iframe;
	struct mbuf *m;

	KILL_TIMER (hdp);

	if (buf == 0) {
		printf ("hd_send_iframe: zero arg\n");
#ifdef HDLCDEBUG
		hd_status (hdp);
		hd_dumptrace (hdp);
#endif
		hdp->hd_vs = (hdp->hd_vs + 7) % MODULUS;
		return;
	}
	iframe = mtod (buf, struct Hdlc_iframe *);

	iframe -> hdlc_0 = 0;
	iframe -> nr = hdp->hd_vr;
	iframe -> pf = poll_bit;
	iframe -> ns = hdp->hd_vs;
	iframe -> address = ADDRESS_B;
	hdp->hd_lasttxnr = hdp->hd_vr;
	hdp->hd_rrtimer = 0;

	if (hdp->hd_vs == hdp->hd_retxqi) {
		/* Check for retransmissions. */
		/* Put iframe only once in the Retransmission queue. */
		hdp->hd_retxq[hdp->hd_retxqi] = buf;
		hdp->hd_retxqi = (hdp->hd_retxqi + 1) % MODULUS;
		hdp->hd_iframes_out++;
	}

	hdp->hd_vs = (hdp->hd_vs + 1) % MODULUS;

	hd_trace (hdp, TX, (struct Hdlc_frame *)iframe);

	/* Write buffer on device. */
	m = hdp->hd_dontcopy ? buf : m_copy(buf, 0, (int)M_COPYALL);
	if (m == 0) {
		printf("hdlc: out of mbufs\n");
		return;
	}
	(*hdp->hd_output)(hdp, m);
	SET_TIMER (hdp);
}

hd_ifoutput(hdp, m)
register struct mbuf *m;
register struct hdcb *hdp;
{
	/*
	 * Queue message on interface, and start output if interface
	 * not yet active.
	 */
	register struct ifnet *ifp = hdp->hd_ifp;
	int s = splimp();

	if (IF_QFULL(&ifp->if_snd)) {
		IF_DROP(&ifp->if_snd);
	    /* printf("%s%d: HDLC says OK to send but queue full, may hang\n",
			ifp->if_name, ifp->if_unit);*/
		m_freem(m);
	} else {
		IF_ENQUEUE(&ifp->if_snd, m);
		if ((ifp->if_flags & IFF_OACTIVE) == 0)
			(*ifp->if_start)(ifp);
	}
	splx(s);
}


/* 
 *  This routine gets control when the timer expires because we have not
 *  received an acknowledgement for a iframe.
 */

hd_resend_iframe (hdp)
register struct hdcb *hdp;
{

	if (hdp->hd_retxcnt++ < hd_n2) {
		if (!(hdp->hd_condition & TIMER_RECOVERY_CONDITION)) {
			hdp->hd_xx = hdp->hd_vs;
			hdp->hd_condition |= TIMER_RECOVERY_CONDITION;
		}

		hdp->hd_vs = hdp->hd_lastrxnr;
		hd_send_iframe (hdp, hdp->hd_retxq[hdp->hd_vs], POLLON);
	} else {
		/* At this point we have not received a RR even after N2
		   retries - attempt to reset link. */

		hd_initvars (hdp);
		hd_writeinternal (hdp, SABM, POLLOFF);
		hdp->hd_state = WAIT_UA;
		SET_TIMER (hdp);
		hd_message (hdp, "Timer recovery failed: link down");
		(void) pk_ctlinput (PRC_LINKDOWN, hdp->hd_pkp);
	}
}
Commit	Line	Data
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
	11	*
	12	* This Original Code and all software distributed under the License are
	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
	19	*
	20	* @APPLE_LICENSE_HEADER_END@
	21	*/
	22	/*
	23	* Copyright (c) University of British Columbia, 1984
	24	* Copyright (c) 1990, 1993
	25	* The Regents of the University of California. All rights reserved.
	26	*
	27	* This code is derived from software contributed to Berkeley by
	28	* the Laboratory for Computation Vision and the Computer Science Department
	29	* of the University of British Columbia.
	30	*
	31	* Redistribution and use in source and binary forms, with or without
	32	* modification, are permitted provided that the following conditions
	33	* are met:
	34	* 1. Redistributions of source code must retain the above copyright
	35	* notice, this list of conditions and the following disclaimer.
	36	* 2. Redistributions in binary form must reproduce the above copyright
	37	* notice, this list of conditions and the following disclaimer in the
	38	* documentation and/or other materials provided with the distribution.
	39	* 3. All advertising materials mentioning features or use of this software
	40	* must display the following acknowledgement:
	41	* This product includes software developed by the University of
	42	* California, Berkeley and its contributors.
	43	* 4. Neither the name of the University nor the names of its contributors
	44	* may be used to endorse or promote products derived from this software
	45	* without specific prior written permission.
	46	*
	47	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	48	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	49	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	50	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	51	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	52	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	53	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	54	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	55	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	56	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	57	* SUCH DAMAGE.
	58	*
	59	* @(#)hd_output.c 8.1 (Berkeley) 6/10/93
	60	*/
	61
	62	#include <sys/param.h>
	63	#include <sys/systm.h>
	64	#include <sys/mbuf.h>
65	#include <sys/domain.h>
66	#include <sys/socket.h>
67	#include <sys/syslog.h>
68	#include <sys/protosw.h>
69	#include <sys/errno.h>
70	#include <sys/time.h>
71	#include <sys/kernel.h>
72
73	#include <net/if.h>
74
75	#include <netccitt/hdlc.h>
76	#include <netccitt/hd_var.h>
77	#include <netccitt/x25.h>
78
79	/*
80	* HDLC OUTPUT INTERFACE
81	*
82	* This routine is called when the X.25 packet layer output routine
83	* has a information frame (iframe) to write. It is also called
84	* by the input and control routines of the HDLC layer.
85	*/
86
87	hd_output (hdp, m0)
88	register struct hdcb *hdp;
89	struct mbuf *m0;
90	{
91	struct x25config *xcp;
92	register struct mbuf *m = m0;
93	int len;
94
95	if (m == NULL)
96	panic ("hd_output");
97	if ((m->m_flags & M_PKTHDR) == 0)
98	panic ("hd_output 2");
99
100	if (hdp->hd_state != ABM) {
101	m_freem (m);
102	return;
103	}
104
105	/*
106	* Make room for the hdlc header either by prepending
107	* another mbuf, or by adjusting the offset and length
108	* of the first mbuf in the mbuf chain.
109	*/
110
111	M_PREPEND(m, HDHEADERLN, M_DONTWAIT);
112	if (m == NULL)
113	return;
114	for (len = 0; m; m = m->m_next)
115	len += m->m_len;
116	m = m0;
117	m->m_pkthdr.len = len;
118
119	hd_append (&hdp->hd_txq, m);
120	hd_start (hdp);
121	}
122
123	hd_start (hdp)
124	register struct hdcb *hdp;
125	{
126	register struct mbuf *m;
127
128	/*
129	* The iframe is only transmitted if all these conditions are FALSE.
130	* The iframe remains queued (hdp->hd_txq) however and will be
131	* transmitted as soon as these conditions are cleared.
132	*/
133
134	while (!(hdp->hd_condition & (TIMER_RECOVERY_CONDITION \| REMOTE_RNR_CONDITION \| REJ_CONDITION))) {
135	if (hdp->hd_vs == (hdp->hd_lastrxnr + hdp->hd_xcp->xc_lwsize) % MODULUS) {
136
137	/* We have now exceeded the maximum number of
138	outstanding iframes. Therefore, we must wait
139	until at least one is acknowledged if this
140	condition is not turned off before we are
141	requested to write another iframe. */
142	hdp->hd_window_condition++;
143	break;
144	}
145
146	/* hd_remove top iframe from transmit queue. */
147	if ((m = hd_remove (&hdp->hd_txq)) == NULL)
148	break;
149
150	hd_send_iframe (hdp, m, POLLOFF);
151	}
152	}
153
154	/*
155	* This procedure is passed a buffer descriptor for an iframe. It builds
156	* the rest of the control part of the frame and then writes it out. It
157	* also starts the acknowledgement timer and keeps the iframe in the
158	* Retransmit queue (Retxq) just in case we have to do this again.
159	*
160	* Note: This routine is also called from hd_input.c when retransmission
161	* of old frames is required.
162	*/
163
164	hd_send_iframe (hdp, buf, poll_bit)
165	register struct hdcb *hdp;
166	register struct mbuf *buf;
167	int poll_bit;
168	{
169	register struct Hdlc_iframe *iframe;
170	struct mbuf *m;
171
172	KILL_TIMER (hdp);
173
174	if (buf == 0) {
175	printf ("hd_send_iframe: zero arg\n");
176	#ifdef HDLCDEBUG
177	hd_status (hdp);
178	hd_dumptrace (hdp);
179	#endif
180	hdp->hd_vs = (hdp->hd_vs + 7) % MODULUS;
181	return;
182	}
183	iframe = mtod (buf, struct Hdlc_iframe *);
184
185	iframe -> hdlc_0 = 0;
186	iframe -> nr = hdp->hd_vr;
187	iframe -> pf = poll_bit;
188	iframe -> ns = hdp->hd_vs;
189	iframe -> address = ADDRESS_B;
190	hdp->hd_lasttxnr = hdp->hd_vr;
191	hdp->hd_rrtimer = 0;
192
193	if (hdp->hd_vs == hdp->hd_retxqi) {
194	/* Check for retransmissions. */
195	/* Put iframe only once in the Retransmission queue. */
196	hdp->hd_retxq[hdp->hd_retxqi] = buf;
197	hdp->hd_retxqi = (hdp->hd_retxqi + 1) % MODULUS;
198	hdp->hd_iframes_out++;
199	}
200
201	hdp->hd_vs = (hdp->hd_vs + 1) % MODULUS;
202
203	hd_trace (hdp, TX, (struct Hdlc_frame *)iframe);
204
205	/* Write buffer on device. */
206	m = hdp->hd_dontcopy ? buf : m_copy(buf, 0, (int)M_COPYALL);
207	if (m == 0) {
208	printf("hdlc: out of mbufs\n");
209	return;
210	}
211	(*hdp->hd_output)(hdp, m);
212	SET_TIMER (hdp);
213	}
214
215	hd_ifoutput(hdp, m)
216	register struct mbuf *m;
217	register struct hdcb *hdp;
218	{
219	/*
220	* Queue message on interface, and start output if interface
221	* not yet active.
222	*/
223	register struct ifnet *ifp = hdp->hd_ifp;
224	int s = splimp();
225
226	if (IF_QFULL(&ifp->if_snd)) {
227	IF_DROP(&ifp->if_snd);
228	/* printf("%s%d: HDLC says OK to send but queue full, may hang\n",
229	ifp->if_name, ifp->if_unit);*/
230	m_freem(m);
231	} else {
232	IF_ENQUEUE(&ifp->if_snd, m);
233	if ((ifp->if_flags & IFF_OACTIVE) == 0)
234	(*ifp->if_start)(ifp);
235	}
236	splx(s);
237	}
238
239
240	/*
241	* This routine gets control when the timer expires because we have not
242	* received an acknowledgement for a iframe.
243	*/
244
245	hd_resend_iframe (hdp)
246	register struct hdcb *hdp;
247	{
248
249	if (hdp->hd_retxcnt++ < hd_n2) {
250	if (!(hdp->hd_condition & TIMER_RECOVERY_CONDITION)) {
251	hdp->hd_xx = hdp->hd_vs;
252	hdp->hd_condition \|= TIMER_RECOVERY_CONDITION;
253	}
254
255	hdp->hd_vs = hdp->hd_lastrxnr;
256	hd_send_iframe (hdp, hdp->hd_retxq[hdp->hd_vs], POLLON);
257	} else {
258	/* At this point we have not received a RR even after N2
259	retries - attempt to reset link. */
260
261	hd_initvars (hdp);
262	hd_writeinternal (hdp, SABM, POLLOFF);
263	hdp->hd_state = WAIT_UA;
264	SET_TIMER (hdp);
265	hd_message (hdp, "Timer recovery failed: link down");
266	(void) pk_ctlinput (PRC_LINKDOWN, hdp->hd_pkp);
267	}
268	}