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/*	$NetBSD: altq_blue.c,v 1.21 2006/11/16 01:32:37 christos Exp $	*/
30/*	$KAME: altq_blue.c,v 1.15 2005/04/13 03:44:24 suz Exp $	*/
31
32/*
33 * Copyright (C) 1997-2002
34 *	Sony Computer Science Laboratories Inc.  All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 *    notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 *    notice, this list of conditions and the following disclaimer in the
43 *    documentation and/or other materials provided with the distribution.
44 *
45 * THIS SOFTWARE IS PROVIDED BY SONY CSL AND CONTRIBUTORS ``AS IS'' AND
46 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
47 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
48 * ARE DISCLAIMED.  IN NO EVENT SHALL SONY CSL OR CONTRIBUTORS BE LIABLE
49 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
50 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
51 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
52 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
53 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
54 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
55 * SUCH DAMAGE.
56 *
57 */
58/*
59 * Copyright (c) 1990-1994 Regents of the University of California.
60 * All rights reserved.
61 *
62 * Redistribution and use in source and binary forms, with or without
63 * modification, are permitted provided that the following conditions
64 * are met:
65 * 1. Redistributions of source code must retain the above copyright
66 *    notice, this list of conditions and the following disclaimer.
67 * 2. Redistributions in binary form must reproduce the above copyright
68 *    notice, this list of conditions and the following disclaimer in the
69 *    documentation and/or other materials provided with the distribution.
70 * 3. All advertising materials mentioning features or use of this software
71 *    must display the following acknowledgement:
72 *	This product includes software developed by the Computer Systems
73 *	Engineering Group at Lawrence Berkeley Laboratory.
74 * 4. Neither the name of the University nor of the Laboratory may be used
75 *    to endorse or promote products derived from this software without
76 *    specific prior written permission.
77 *
78 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
79 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
80 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
81 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
82 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
83 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
84 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
85 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
86 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
87 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
88 * SUCH DAMAGE.
89 */
90
91#include <sys/cdefs.h>
92
93#if CLASSQ_BLUE
94
95#include <sys/param.h>
96#include <sys/malloc.h>
97#include <sys/mbuf.h>
98#include <sys/socket.h>
99#include <sys/sockio.h>
100#include <sys/systm.h>
101#include <sys/proc.h>
102#include <sys/errno.h>
103#include <sys/kernel.h>
104#include <sys/kauth.h>
105
106#include <kern/zalloc.h>
107
108#include <net/if.h>
109#include <net/if_var.h>
110#include <net/if_types.h>
111
112#include <netinet/in.h>
113#include <netinet/in_systm.h>
114#include <netinet/ip.h>
115#if INET6
116#include <netinet/ip6.h>
117#endif
118
119#include <net/classq/classq_blue.h>
120#include <net/net_osdep.h>
121
122/*
123 * Blue is proposed and implemented by Wu-chang Feng <wuchang@eecs.umich.edu>.
124 * more information on Blue is available from
125 * http://www.eecs.umich.edu/~wuchang/blue/
126 */
127
128#define	BLUE_LIMIT	200		/* default max queue lenght */
129
130#define	BLUE_ZONE_MAX	32		/* maximum elements in zone */
131#define	BLUE_ZONE_NAME	"classq_blue"	/* zone name */
132
133static unsigned int blue_size;		/* size of zone element */
134static struct zone *blue_zone;		/* zone for blue */
135
136/* internal function prototypes */
137static struct mbuf *blue_getq_flow(struct blue *, class_queue_t *,
138    u_int32_t, boolean_t);
139static int blue_drop_early(struct blue *);
140
141void
142blue_init(void)
143{
144	_CASSERT(BLUEF_ECN4 == CLASSQF_ECN4);
145	_CASSERT(BLUEF_ECN6 == CLASSQF_ECN6);
146
147	blue_size = sizeof (struct blue);
148	blue_zone = zinit(blue_size, BLUE_ZONE_MAX * blue_size,
149	    0, BLUE_ZONE_NAME);
150	if (blue_zone == NULL) {
151		panic("%s: failed allocating %s", __func__, BLUE_ZONE_NAME);
152		/* NOTREACHED */
153	}
154	zone_change(blue_zone, Z_EXPAND, TRUE);
155	zone_change(blue_zone, Z_CALLERACCT, TRUE);
156}
157
158/*
159 * blue support routines
160 */
161struct blue *
162blue_alloc(struct ifnet *ifp, u_int32_t max_pmark, u_int32_t hold_time,
163    u_int32_t flags)
164{
165	struct blue *bp;
166
167	VERIFY(ifp != NULL);
168
169	bp = zalloc(blue_zone);
170	if (bp == NULL)
171		return (NULL);
172
173	bzero(bp, blue_size);
174	bp->blue_idle = 1;
175	bp->blue_flags = (flags & BLUEF_USERFLAGS);
176	bp->blue_ifp = ifp;
177
178	if (max_pmark == 0)
179		bp->blue_max_pmark = 1000;
180	else
181		bp->blue_max_pmark = max_pmark;
182
183	if (hold_time == 0)
184		bp->blue_hold_time = 50000;
185	else
186		bp->blue_hold_time = hold_time;
187
188	microuptime(&bp->blue_last);
189
190	return (bp);
191}
192
193void
194blue_destroy(struct blue *bp)
195{
196	zfree(blue_zone, bp);
197}
198
199void
200blue_getstats(struct blue *bp, struct blue_stats *sp)
201{
202	sp->q_pmark		= bp->blue_pmark;
203	sp->drop_forced		= bp->blue_stats.drop_forced;
204	sp->drop_unforced	= bp->blue_stats.drop_unforced;
205	sp->marked_packets	= bp->blue_stats.marked_packets;
206}
207
208#define	DTYPE_NODROP	0	/* no drop */
209#define	DTYPE_FORCED	1	/* a "forced" drop */
210#define	DTYPE_EARLY	2	/* an "unforced" (early) drop */
211
212int
213blue_addq(struct blue *bp, class_queue_t *q, struct mbuf *m,
214    struct pf_mtag *tag)
215{
216	int droptype;
217
218	/*
219	 * if we were idle, this is an enqueue onto an empty queue
220	 * and we should decrement marking probability
221	 */
222	if (bp->blue_idle) {
223		struct timeval now;
224		u_int32_t t;
225
226		bp->blue_idle = 0;
227		microuptime(&now);
228		t = (now.tv_sec - bp->blue_last.tv_sec);
229		if (t > 1) {
230			bp->blue_pmark = 1;
231			microuptime(&bp->blue_last);
232		} else {
233			t = t * 1000000 + (now.tv_usec - bp->blue_last.tv_usec);
234			if (t > bp->blue_hold_time) {
235				bp->blue_pmark--;
236				if (bp->blue_pmark < 0)
237					bp->blue_pmark = 0;
238				microuptime(&bp->blue_last);
239			}
240		}
241	}
242
243	/* see if we drop early */
244	droptype = DTYPE_NODROP;
245	if (blue_drop_early(bp) && qlen(q) > 1) {
246		/* mark or drop by blue */
247		if ((bp->blue_flags & BLUEF_ECN) &&
248		    (tag->pftag_flags & PF_TAG_TCP) &&	/* only for TCP */
249		    mark_ecn(m, tag, bp->blue_flags)) {
250			/* successfully marked.  do not drop. */
251			bp->blue_stats.marked_packets++;
252		} else {
253			/* unforced drop by blue */
254			droptype = DTYPE_EARLY;
255		}
256	}
257
258	/* if the queue length hits the hard limit, it's a forced drop */
259	if (droptype == DTYPE_NODROP && qlen(q) >= qlimit(q))
260		droptype = DTYPE_FORCED;
261
262	/* if successful or forced drop, enqueue this packet. */
263	if (droptype != DTYPE_EARLY)
264		_addq(q, m);
265
266	if (droptype != DTYPE_NODROP) {
267		if (droptype == DTYPE_EARLY) {
268			/* drop the incoming packet */
269			bp->blue_stats.drop_unforced++;
270		} else {
271			struct timeval now;
272			u_int32_t t;
273			/* forced drop, select a victim packet in the queue. */
274			m = _getq_random(q);
275			microuptime(&now);
276			t = (now.tv_sec - bp->blue_last.tv_sec);
277			t = t * 1000000 + (now.tv_usec - bp->blue_last.tv_usec);
278			if (t > bp->blue_hold_time) {
279				bp->blue_pmark += bp->blue_max_pmark >> 3;
280				if (bp->blue_pmark > bp->blue_max_pmark)
281					bp->blue_pmark = bp->blue_max_pmark;
282				microuptime(&bp->blue_last);
283			}
284			bp->blue_stats.drop_forced++;
285		}
286		IFCQ_CONVERT_LOCK(&bp->blue_ifp->if_snd);
287		m_freem(m);
288		return (CLASSQEQ_DROPPED);
289	}
290	/* successfully queued */
291	return (CLASSQEQ_SUCCESS);
292}
293
294static struct mbuf *
295blue_getq_flow(struct blue *bp, class_queue_t *q, u_int32_t flow,
296    boolean_t purge)
297{
298#pragma unused(purge)
299	struct mbuf *m;
300
301	/* flow of 0 means head of queue */
302	if ((m = ((flow == 0) ? _getq(q) : _getq_flow(q, flow))) == NULL) {
303		if (bp->blue_idle == 0) {
304			bp->blue_idle = 1;
305			microuptime(&bp->blue_last);
306		}
307		return (NULL);
308	}
309
310	bp->blue_idle = 0;
311	return (m);
312}
313
314struct mbuf *
315blue_getq(struct blue *bp, class_queue_t *q)
316{
317	return (blue_getq_flow(bp, q, 0, FALSE));
318}
319
320void
321blue_purgeq(struct blue *bp, class_queue_t *q, u_int32_t flow,
322    u_int32_t *packets, u_int32_t *bytes)
323{
324	u_int32_t cnt = 0, len = 0;
325	struct mbuf *m;
326
327	IFCQ_CONVERT_LOCK(&bp->blue_ifp->if_snd);
328
329	while ((m = blue_getq_flow(bp, q, flow, TRUE)) != NULL) {
330		cnt++;
331		len += m_pktlen(m);
332		m_freem(m);
333	}
334
335	if (packets != NULL)
336		*packets = cnt;
337	if (bytes != NULL)
338		*bytes = len;
339}
340
341/*
342 * early-drop probability is kept in blue_pmark
343 */
344static int
345blue_drop_early(struct blue *bp)
346{
347	if ((random() % (unsigned)bp->blue_max_pmark) <
348	    (unsigned)bp->blue_pmark) {
349		/* drop or mark */
350		return (1);
351	}
352	/* no drop/mark */
353	return (0);
354}
355
356void
357blue_updateq(struct blue *bp, cqev_t ev)
358{
359#pragma unused(bp, ev)
360	/* nothing for now */
361}
362
363int
364blue_suspendq(struct blue *bp, class_queue_t *q, boolean_t on)
365{
366#pragma unused(bp, q, on)
367	return (ENOTSUP);
368}
369#endif /* CLASSQ_BLUE */
370