[apple/xnu.git] / bsd / net / classq / classq.c

/*
 * Copyright (c) 2007-2012 Apple Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 *
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 *
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 *
 * The 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, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */

/*
 * Copyright (c) 1991-1997 Regents of the University of California.
 * All rights reserved.
 *
 * 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 Network Research
 *      Group at Lawrence Berkeley Laboratory.
 * 4. Neither the name of the University nor of the Laboratory 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.
 */

#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/mbuf.h>
#include <sys/errno.h>
#include <sys/random.h>
#include <sys/kernel_types.h>
#include <sys/sysctl.h>

#include <net/if.h>
#include <net/net_osdep.h>
#include <net/classq/classq.h>

#include <libkern/libkern.h>

u_int32_t classq_verbose;	/* more noise if greater than 1 */

SYSCTL_NODE(_net, OID_AUTO, classq, CTLFLAG_RW|CTLFLAG_LOCKED, 0, "classq");

SYSCTL_UINT(_net_classq, OID_AUTO, verbose, CTLFLAG_RW|CTLFLAG_LOCKED,
	&classq_verbose, 0, "Class queue verbosity level");

void
_qinit(class_queue_t *q, int type, int lim)
{
	MBUFQ_INIT(&q->mbufq);
	qlimit(q) = lim;
	qlen(q) = 0;
	qsize(q) = 0;
	qtype(q) = type;
	qstate(q) = QS_RUNNING;
}

/* add a packet at the tail of the queue */
void
_addq(class_queue_t *q, struct mbuf *m)
{
	MBUFQ_ENQUEUE(&q->mbufq, m);
	qlen(q)++;
	VERIFY(qlen(q) != 0);
	qsize(q) += m_length(m);
}

/* add one or more packets at the tail of the queue */
void
_addq_multi(class_queue_t *q, struct mbuf *m_head, struct mbuf *m_tail,
    u_int32_t cnt, u_int32_t size)
{
	MBUFQ_ENQUEUE_MULTI(&q->mbufq, m_head, m_tail);
	qlen(q) += cnt;
	qsize(q) += size;
}

/* get a packet at the head of the queue */
struct mbuf *
_getq(class_queue_t *q)
{
	struct mbuf *m;

	MBUFQ_DEQUEUE(&q->mbufq, m);
	if (m == NULL) {
		VERIFY(qlen(q) == 0);
		if (qsize(q) > 0)
			qsize(q) = 0;
		return (NULL);
	}
	VERIFY(qlen(q) > 0);
	qlen(q)--;

	/* qsize is an approximation, so adjust if necessary */
	if (((int)qsize(q) - m_length(m)) > 0)
		qsize(q) -= m_length(m);
	else if (qsize(q) != 0)
		qsize(q) = 0;

	return (m);
}

/* get a packet of a specific flow beginning from the head of the queue */
struct mbuf *
_getq_flow(class_queue_t *q, u_int32_t flow)
{
	struct mbuf *m, *m_tmp;

	MBUFQ_FOREACH_SAFE(m, &q->mbufq, m_tmp) {
		if (flow == 0 || ((m->m_flags & M_PKTHDR) &&
		    m->m_pkthdr.pkt_flowid == flow)) {
			/* remove it from the class queue */
			MBUFQ_REMOVE(&q->mbufq, m);
			MBUFQ_NEXT(m) = NULL;
			break;
		}
	}

	if (m != NULL) {
		u_int32_t l = m_length(m);

		VERIFY(qlen(q) > 0);
		qlen(q)--;

		/* qsize is an approximation, so adjust if necessary */
		if (((int)qsize(q) - l) > 0)
			qsize(q) -= l;
		else if (qsize(q) != 0)
			qsize(q) = 0;
	}

	return (m);
}

/* get all packets starting from the head of the queue */
struct mbuf *
_getq_all(class_queue_t *q)
{
	struct mbuf *m;

	m = MBUFQ_FIRST(&q->mbufq);
	MBUFQ_INIT(&q->mbufq);
	qlen(q) = 0;
	qsize(q) = 0;

	return (m);
}

/* drop a packet at the tail of the queue */
struct mbuf *
_getq_tail(class_queue_t *q)
{
	struct mq_head *head = &q->mbufq;
	struct mbuf *m = MBUFQ_LAST(head);

	if (m != NULL) {
		struct mbuf *n = MBUFQ_FIRST(head);

		while (n != NULL) {
			struct mbuf *next = MBUFQ_NEXT(n);
			if (next == m) {
				MBUFQ_NEXT(n) = NULL;
				break;
			}
			n = next;
		}
		VERIFY(n != NULL ||
		    (qlen(q) == 1 && m == MBUFQ_FIRST(head)));
		VERIFY(qlen(q) > 0);
		--qlen(q);

		/* qsize is an approximation, so adjust if necessary */
		if (((int)qsize(q) - m_length(m)) > 0)
			qsize(q) -= m_length(m);
		else if (qsize(q) != 0)
			qsize(q) = 0;

		if (qempty(q)) {
			VERIFY(MBUFQ_EMPTY(head));
			MBUFQ_INIT(head);
		} else {
			VERIFY(n != NULL);
			head->mq_last = &MBUFQ_NEXT(n);
		}
	}
	return (m);
}

/* randomly select a packet in the queue */
struct mbuf *
_getq_random(class_queue_t *q)
{
	struct mq_head *head = &q->mbufq;
	struct mbuf *m = NULL;
	unsigned int n;
	u_int32_t rnd;

	n = qlen(q);
	if (n == 0) {
		VERIFY(MBUFQ_EMPTY(head));
		if (qsize(q) > 0)
			qsize(q) = 0;
		return (NULL);
	}

	m = MBUFQ_FIRST(head);
	read_random(&rnd, sizeof (rnd));
	n = (rnd % n) + 1;

	if (n == 1) {
		if ((MBUFQ_FIRST(head) = MBUFQ_NEXT(m)) == NULL)
			(head)->mq_last = &MBUFQ_FIRST(head);
	} else {
		struct mbuf *p = NULL;

		VERIFY(n > 1);
		while (n--) {
			if (MBUFQ_NEXT(m) == NULL)
				break;
			p = m;
			m = MBUFQ_NEXT(m);
		}
		VERIFY(p != NULL && MBUFQ_NEXT(p) == m);

		if ((MBUFQ_NEXT(p) = MBUFQ_NEXT(m)) == NULL)
			(head)->mq_last = &MBUFQ_NEXT(p);
	}

	VERIFY(qlen(q) > 0);
	--qlen(q);

	/* qsize is an approximation, so adjust if necessary */
	if (((int)qsize(q) - m_length(m)) > 0)
		qsize(q) -= m_length(m);
	else if (qsize(q) != 0)
		qsize(q) = 0;

	MBUFQ_NEXT(m) = NULL;

	return (m);
}

/* remove a packet from the queue */
void
_removeq(class_queue_t *q, struct mbuf *m)
{
	struct mq_head *head = &q->mbufq;
	struct mbuf *m0, **mtail;

	m0 = MBUFQ_FIRST(head);
	if (m0 == NULL)
		return;

	if (m0 != m) {
		while (MBUFQ_NEXT(m0) != m) {
			if (m0 == NULL)
				return;
			m0 = MBUFQ_NEXT(m0);
		}
		mtail = &MBUFQ_NEXT(m0);
	} else {
		mtail = &MBUFQ_FIRST(head);
	}

	*mtail = MBUFQ_NEXT(m);
	if (*mtail == NULL)
		head->mq_last = mtail;

	VERIFY(qlen(q) > 0);
	--qlen(q);

	/* qsize is an approximation, so adjust if necessary */
	if (((int)qsize(q) - m_length(m)) > 0)
		qsize(q) -= m_length(m);
	else if (qsize(q) != 0)
		qsize(q) = 0;

	MBUFQ_NEXT(m) = NULL;
}

void
_flushq(class_queue_t *q)
{
	(void) _flushq_flow(q, 0, NULL, NULL);
}

void
_flushq_flow(class_queue_t *q, u_int32_t flow, u_int32_t *cnt, u_int32_t *len)
{
	MBUFQ_HEAD(mq_freeq) freeq;
	struct mbuf *m, *m_tmp;
	u_int32_t c = 0, l = 0;

	MBUFQ_INIT(&freeq);

	MBUFQ_FOREACH_SAFE(m, &q->mbufq, m_tmp) {
		if (flow == 0 || ((m->m_flags & M_PKTHDR) &&
		    m->m_pkthdr.pkt_flowid == flow)) {
			/* remove it from the class queue */
			MBUFQ_REMOVE(&q->mbufq, m);
			MBUFQ_NEXT(m) = NULL;

			/* and add it to the free queue */
			MBUFQ_ENQUEUE(&freeq, m);

			l += m_length(m);
			c++;
		}
	}
	VERIFY(c == 0 || !MBUFQ_EMPTY(&freeq));

	if (c > 0) {
		VERIFY(qlen(q) >= c);
		qlen(q) -= c;

		/* qsize is an approximation, so adjust if necessary */
		if (((int)qsize(q) - l) > 0)
			qsize(q) -= l;
		else if (qsize(q) != 0)
			qsize(q) = 0;
	}

	if (!MBUFQ_EMPTY(&freeq))
		m_freem_list(MBUFQ_FIRST(&freeq));

	if (cnt != NULL)
		*cnt = c;
	if (len != NULL)
		*len = l;
}
Commit	Line	Data
316670eb A	1	/*
	2	* Copyright (c) 2007-2012 Apple Inc. All rights reserved.
	3	*
	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
	5	*
	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
	25	*
	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
	27	*/
	28
	29	/*
	30	* Copyright (c) 1991-1997 Regents of the University of California.
	31	* All rights reserved.
	32	*
	33	* Redistribution and use in source and binary forms, with or without
	34	* modification, are permitted provided that the following conditions
	35	* are met:
	36	* 1. Redistributions of source code must retain the above copyright
	37	* notice, this list of conditions and the following disclaimer.
	38	* 2. Redistributions in binary form must reproduce the above copyright
	39	* notice, this list of conditions and the following disclaimer in the
	40	* documentation and/or other materials provided with the distribution.
	41	* 3. All advertising materials mentioning features or use of this software
	42	* must display the following acknowledgement:
	43	* This product includes software developed by the Network Research
	44	* Group at Lawrence Berkeley Laboratory.
	45	* 4. Neither the name of the University nor of the Laboratory may be used
	46	* to endorse or promote products derived from this software without
	47	* specific prior written permission.
	48	*
	49	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	50	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	51	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	52	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	53	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	54	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	55	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	56	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	57	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	58	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	59	* SUCH DAMAGE.
	60	*/
	61
	62	#include <sys/cdefs.h>
	63	#include <sys/param.h>
	64	#include <sys/mbuf.h>
65	#include <sys/errno.h>
66	#include <sys/random.h>
67	#include <sys/kernel_types.h>
68	#include <sys/sysctl.h>
69
70	#include <net/if.h>
71	#include <net/net_osdep.h>
72	#include <net/classq/classq.h>
73
74	#include <libkern/libkern.h>
75
76	u_int32_t classq_verbose; /* more noise if greater than 1 */
77
78	SYSCTL_NODE(_net, OID_AUTO, classq, CTLFLAG_RW\|CTLFLAG_LOCKED, 0, "classq");
79
80	SYSCTL_UINT(_net_classq, OID_AUTO, verbose, CTLFLAG_RW\|CTLFLAG_LOCKED,
81	&classq_verbose, 0, "Class queue verbosity level");
82
83	void
84	_qinit(class_queue_t *q, int type, int lim)
85	{
86	MBUFQ_INIT(&q->mbufq);
87	qlimit(q) = lim;
88	qlen(q) = 0;
89	qsize(q) = 0;
90	qtype(q) = type;
91	qstate(q) = QS_RUNNING;
92	}
93
94	/* add a packet at the tail of the queue */
95	void
96	_addq(class_queue_t q, struct mbuf m)
97	{
98	MBUFQ_ENQUEUE(&q->mbufq, m);
99	qlen(q)++;
100	VERIFY(qlen(q) != 0);
101	qsize(q) += m_length(m);
102	}
103
104	/* add one or more packets at the tail of the queue */
105	void
106	_addq_multi(class_queue_t q, struct mbuf m_head, struct mbuf *m_tail,
107	u_int32_t cnt, u_int32_t size)
108	{
109	MBUFQ_ENQUEUE_MULTI(&q->mbufq, m_head, m_tail);
110	qlen(q) += cnt;
111	qsize(q) += size;
112	}
113
114	/* get a packet at the head of the queue */
115	struct mbuf *
116	_getq(class_queue_t *q)
117	{
118	struct mbuf *m;
119
120	MBUFQ_DEQUEUE(&q->mbufq, m);
121	if (m == NULL) {
122	VERIFY(qlen(q) == 0);
123	if (qsize(q) > 0)
124	qsize(q) = 0;
125	return (NULL);
126	}
127	VERIFY(qlen(q) > 0);
128	qlen(q)--;
129
130	/* qsize is an approximation, so adjust if necessary */
131	if (((int)qsize(q) - m_length(m)) > 0)
132	qsize(q) -= m_length(m);
133	else if (qsize(q) != 0)
134	qsize(q) = 0;
135
136	return (m);
137	}
138
139	/* get a packet of a specific flow beginning from the head of the queue */
140	struct mbuf *
141	_getq_flow(class_queue_t *q, u_int32_t flow)
142	{
143	struct mbuf m, m_tmp;
144
145	MBUFQ_FOREACH_SAFE(m, &q->mbufq, m_tmp) {
146	if (flow == 0 \|\| ((m->m_flags & M_PKTHDR) &&
39236c6e	147	m->m_pkthdr.pkt_flowid == flow)) {
316670eb A	148	/* remove it from the class queue */
	149	MBUFQ_REMOVE(&q->mbufq, m);
	150	MBUFQ_NEXT(m) = NULL;
	151	break;
	152	}
	153	}
	154
	155	if (m != NULL) {
	156	u_int32_t l = m_length(m);
	157
	158	VERIFY(qlen(q) > 0);
	159	qlen(q)--;
	160
	161	/* qsize is an approximation, so adjust if necessary */
	162	if (((int)qsize(q) - l) > 0)
	163	qsize(q) -= l;
	164	else if (qsize(q) != 0)
	165	qsize(q) = 0;
	166	}
	167
	168	return (m);
	169	}
	170
	171	/* get all packets starting from the head of the queue */
	172	struct mbuf *
	173	_getq_all(class_queue_t *q)
	174	{
	175	struct mbuf *m;
	176
	177	m = MBUFQ_FIRST(&q->mbufq);
	178	MBUFQ_INIT(&q->mbufq);
	179	qlen(q) = 0;
	180	qsize(q) = 0;
	181
	182	return (m);
	183	}
	184
	185	/* drop a packet at the tail of the queue */
	186	struct mbuf *
	187	_getq_tail(class_queue_t *q)
	188	{
	189	struct mq_head *head = &q->mbufq;
	190	struct mbuf *m = MBUFQ_LAST(head);
	191
	192	if (m != NULL) {
	193	struct mbuf *n = MBUFQ_FIRST(head);
	194
	195	while (n != NULL) {
	196	struct mbuf *next = MBUFQ_NEXT(n);
	197	if (next == m) {
	198	MBUFQ_NEXT(n) = NULL;
	199	break;
	200	}
	201	n = next;
	202	}
	203	VERIFY(n != NULL \|\|
	204	(qlen(q) == 1 && m == MBUFQ_FIRST(head)));
	205	VERIFY(qlen(q) > 0);
	206	--qlen(q);
	207
	208	/* qsize is an approximation, so adjust if necessary */
	209	if (((int)qsize(q) - m_length(m)) > 0)
	210	qsize(q) -= m_length(m);
	211	else if (qsize(q) != 0)
212	qsize(q) = 0;
213
214	if (qempty(q)) {
215	VERIFY(MBUFQ_EMPTY(head));
216	MBUFQ_INIT(head);
217	} else {
218	VERIFY(n != NULL);
219	head->mq_last = &MBUFQ_NEXT(n);
220	}
221	}
222	return (m);
223	}
224
225	/* randomly select a packet in the queue */
226	struct mbuf *
227	_getq_random(class_queue_t *q)
228	{
229	struct mq_head *head = &q->mbufq;
230	struct mbuf *m = NULL;
231	unsigned int n;
232	u_int32_t rnd;
233
234	n = qlen(q);
235	if (n == 0) {
236	VERIFY(MBUFQ_EMPTY(head));
237	if (qsize(q) > 0)
238	qsize(q) = 0;
239	return (NULL);
240	}
241
242	m = MBUFQ_FIRST(head);
243	read_random(&rnd, sizeof (rnd));
244	n = (rnd % n) + 1;
245
246	if (n == 1) {
247	if ((MBUFQ_FIRST(head) = MBUFQ_NEXT(m)) == NULL)
248	(head)->mq_last = &MBUFQ_FIRST(head);
249	} else {
250	struct mbuf *p = NULL;
251
252	VERIFY(n > 1);
253	while (n--) {
254	if (MBUFQ_NEXT(m) == NULL)
255	break;
256	p = m;
257	m = MBUFQ_NEXT(m);
258	}
259	VERIFY(p != NULL && MBUFQ_NEXT(p) == m);
260
261	if ((MBUFQ_NEXT(p) = MBUFQ_NEXT(m)) == NULL)
262	(head)->mq_last = &MBUFQ_NEXT(p);
263	}
264
265	VERIFY(qlen(q) > 0);
266	--qlen(q);
267
268	/* qsize is an approximation, so adjust if necessary */
269	if (((int)qsize(q) - m_length(m)) > 0)
270	qsize(q) -= m_length(m);
271	else if (qsize(q) != 0)
272	qsize(q) = 0;
273
274	MBUFQ_NEXT(m) = NULL;
275
276	return (m);
277	}
278
279	/* remove a packet from the queue */
280	void
281	_removeq(class_queue_t q, struct mbuf m)
282	{
283	struct mq_head *head = &q->mbufq;
284	struct mbuf m0, *mtail;
285
286	m0 = MBUFQ_FIRST(head);
287	if (m0 == NULL)
288	return;
289
290	if (m0 != m) {
291	while (MBUFQ_NEXT(m0) != m) {
292	if (m0 == NULL)
293	return;
294	m0 = MBUFQ_NEXT(m0);
295	}
296	mtail = &MBUFQ_NEXT(m0);
297	} else {
298	mtail = &MBUFQ_FIRST(head);
299	}
300
301	*mtail = MBUFQ_NEXT(m);
302	if (*mtail == NULL)
303	head->mq_last = mtail;
304
305	VERIFY(qlen(q) > 0);
306	--qlen(q);
307
308	/* qsize is an approximation, so adjust if necessary */
309	if (((int)qsize(q) - m_length(m)) > 0)
310	qsize(q) -= m_length(m);
311	else if (qsize(q) != 0)
312	qsize(q) = 0;
313
314	MBUFQ_NEXT(m) = NULL;
315	}
316
317	void
318	_flushq(class_queue_t *q)
319	{
320	(void) _flushq_flow(q, 0, NULL, NULL);
321	}
322
323	void
324	_flushq_flow(class_queue_t q, u_int32_t flow, u_int32_t cnt, u_int32_t *len)
325	{
326	MBUFQ_HEAD(mq_freeq) freeq;
327	struct mbuf m, m_tmp;
328	u_int32_t c = 0, l = 0;
329
330	MBUFQ_INIT(&freeq);
331
332	MBUFQ_FOREACH_SAFE(m, &q->mbufq, m_tmp) {
333	if (flow == 0 \|\| ((m->m_flags & M_PKTHDR) &&
39236c6e	334	m->m_pkthdr.pkt_flowid == flow)) {
316670eb A	335	/* remove it from the class queue */
	336	MBUFQ_REMOVE(&q->mbufq, m);
	337	MBUFQ_NEXT(m) = NULL;
	338
	339	/* and add it to the free queue */
	340	MBUFQ_ENQUEUE(&freeq, m);
	341
	342	l += m_length(m);
	343	c++;
	344	}
	345	}
	346	VERIFY(c == 0 \|\| !MBUFQ_EMPTY(&freeq));
	347
	348	if (c > 0) {
	349	VERIFY(qlen(q) >= c);
	350	qlen(q) -= c;
	351
	352	/* qsize is an approximation, so adjust if necessary */
	353	if (((int)qsize(q) - l) > 0)
	354	qsize(q) -= l;
	355	else if (qsize(q) != 0)
	356	qsize(q) = 0;
	357	}
	358
	359	if (!MBUFQ_EMPTY(&freeq))
	360	m_freem_list(MBUFQ_FIRST(&freeq));
	361
	362	if (cnt != NULL)
	363	*cnt = c;
	364	if (len != NULL)
	365	*len = l;
	366	}