if_ath_alq.c revision 242813 
1/*-
2 * Copyright (c) 2012 Adrian Chadd
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer,
10 *    without modification.
11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
12 *    similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
13 *    redistribution must be conditioned upon including a substantially
14 *    similar Disclaimer requirement for further binary redistribution.
15 *
16 * NO WARRANTY
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
20 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
22 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
25 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
27 * THE POSSIBILITY OF SUCH DAMAGES.
28 *
29 * $FreeBSD: head/sys/dev/ath/if_ath_alq.c 242813 2012-11-09 01:28:11Z adrian $
30 */
31#include "opt_ah.h"
32#include "opt_ath.h"
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#include <sys/kernel.h>
37#include <sys/module.h>
38#include <sys/sysctl.h>
39#include <sys/bus.h>
40#include <sys/malloc.h>
41#include <sys/proc.h>
42#include <sys/pcpu.h>
43#include <sys/lock.h>
44#include <sys/mutex.h>
45#include <sys/alq.h>
46
47#include <dev/ath/if_ath_alq.h>
48
49#ifdef	ATH_DEBUG_ALQ
50static struct ale *
51if_ath_alq_get(struct if_ath_alq *alq, int len)
52{
53	struct ale *ale;
54
55	if (alq->sc_alq_isactive == 0)
56		return (NULL);
57
58	ale = alq_getn(alq->sc_alq_alq, len, ALQ_NOWAIT);
59	if (! ale)
60		alq->sc_alq_numlost++;
61	return (ale);
62}
63
64void
65if_ath_alq_init(struct if_ath_alq *alq, const char *devname)
66{
67
68	bzero(alq, sizeof(*alq));
69
70	strncpy(alq->sc_alq_devname, devname, ATH_ALQ_DEVNAME_LEN);
71	printf("%s (%s): attached\n", __func__, alq->sc_alq_devname);
72	snprintf(alq->sc_alq_filename, ATH_ALQ_FILENAME_LEN,
73	    "/tmp/ath_%s_alq.log", alq->sc_alq_devname);
74
75	/* XXX too conservative, right? */
76	alq->sc_alq_qsize = (64*1024);
77}
78
79void
80if_ath_alq_tidyup(struct if_ath_alq *alq)
81{
82
83	if_ath_alq_stop(alq);
84	printf("%s (%s): detached\n", __func__, alq->sc_alq_devname);
85	bzero(alq, sizeof(*alq));
86}
87
88int
89if_ath_alq_start(struct if_ath_alq *alq)
90{
91	int error;
92
93	if (alq->sc_alq_isactive)
94		return (0);
95
96	/*
97	 * Create a variable-length ALQ.
98	 */
99	error = alq_open(&alq->sc_alq_alq, alq->sc_alq_filename,
100	    curthread->td_ucred, ALQ_DEFAULT_CMODE,
101	    alq->sc_alq_qsize, 0);
102
103	if (error != 0) {
104		printf("%s (%s): failed, err=%d\n", __func__,
105		    alq->sc_alq_devname, error);
106	} else {
107		printf("%s (%s): opened\n", __func__, alq->sc_alq_devname);
108		alq->sc_alq_isactive = 1;
109	}
110	return (error);
111}
112
113int
114if_ath_alq_stop(struct if_ath_alq *alq)
115{
116
117	if (alq->sc_alq_isactive == 0)
118		return (0);
119
120	printf("%s (%s): closed\n", __func__, alq->sc_alq_devname);
121
122	alq->sc_alq_isactive = 0;
123	alq_close(alq->sc_alq_alq);
124	alq->sc_alq_alq = NULL;
125
126	return (0);
127}
128
129/*
130 * Post a debug message to the ALQ.
131 *
132 * "len" is the size of the buf payload in bytes.
133 */
134void
135if_ath_alq_post(struct if_ath_alq *alq, uint16_t op, uint16_t len,
136    const char *buf)
137{
138	struct if_ath_alq_hdr *ap;
139	struct ale *ale;
140
141	if (! if_ath_alq_checkdebug(alq, op))
142		return;
143
144	/*
145	 * Enforce some semblence of sanity on 'len'.
146	 * Although strictly speaking, any length is possible -
147	 * just be conservative so things don't get out of hand.
148	 */
149	if (len > ATH_ALQ_PAYLOAD_LEN)
150		len = ATH_ALQ_PAYLOAD_LEN;
151
152	ale = if_ath_alq_get(alq, len + sizeof(struct if_ath_alq_hdr));
153
154	if (ale == NULL)
155		return;
156
157	ap = (struct if_ath_alq_hdr *) ale->ae_data;
158	ap->threadid = (uint64_t) curthread->td_tid;
159	ap->tstamp = (uint32_t) ticks;
160	ap->op = op;
161	ap->len = len;
162
163	/*
164	 * Copy the payload _after_ the header field.
165	 */
166	memcpy(((char *) ap) + sizeof(struct if_ath_alq_hdr),
167	    buf,
168	    ap->len);
169
170	alq_post(alq->sc_alq_alq, ale);
171}
172#endif	/* ATH_DEBUG */
173