wlan - Rip out all wlan locks part 1/2
[dragonfly.git] / sys / netproto / 802_11 / wlan / ieee80211_ageq.c
CommitLineData
32176cfd
RP
1/*-
2 * Copyright (c) 2009 Sam Leffler, Errno Consulting
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 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 *
25 * $FreeBSD: head/sys/net80211/ieee80211_ageq.c 195527 2009-07-10 02:19:57Z sam $
26 * $DragonFly$
27 */
28
29/*
30 * IEEE 802.11 age queue support.
31 */
32#include "opt_wlan.h"
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#include <sys/kernel.h>
37
38#include <sys/socket.h>
39
40#include <net/if.h>
41#include <net/if_media.h>
42#include <net/ethernet.h>
43#include <net/route.h>
44
45#include <netproto/802_11/ieee80211_var.h>
46
47/*
48 * Initialize an ageq.
49 */
50void
51ieee80211_ageq_init(struct ieee80211_ageq *aq, int maxlen, const char *name)
52{
53 memset(aq, 0, sizeof(aq));
54 aq->aq_maxlen = maxlen;
32176cfd
RP
55}
56
57/*
58 * Cleanup an ageq initialized with ieee80211_ageq_init. Note
59 * the queue is assumed empty; this can be done with ieee80211_ageq_drain.
60 */
61void
62ieee80211_ageq_cleanup(struct ieee80211_ageq *aq)
63{
64 KASSERT(aq->aq_len == 0, ("%d frames on ageq", aq->aq_len));
32176cfd
RP
65}
66
67/*
68 * Free an mbuf according to ageq rules: if marked as holding
69 * and 802.11 frame then also reclaim a node reference from
70 * the packet header; this handles packets q'd in the tx path.
71 */
72static void
73ageq_mfree(struct mbuf *m)
74{
75 if (m->m_flags & M_ENCAP) {
76 struct ieee80211_node *ni = (void *) m->m_pkthdr.rcvif;
77 ieee80211_free_node(ni);
78 }
79 m->m_nextpkt = NULL;
80 m_freem(m);
81}
82
83/*
84 * Free a list of mbufs using ageq rules (see above).
85 */
86void
87ieee80211_ageq_mfree(struct mbuf *m)
88{
89 struct mbuf *next;
90
91 for (; m != NULL; m = next) {
92 next = m->m_nextpkt;
93 ageq_mfree(m);
94 }
95}
96
97/*
98 * Append an mbuf to the ageq and mark it with the specified max age
99 * If the frame is not removed before the age (in seconds) expires
100 * then it is reclaimed (along with any node reference).
101 */
102int
103ieee80211_ageq_append(struct ieee80211_ageq *aq, struct mbuf *m, int age)
104{
32176cfd
RP
105 if (__predict_true(aq->aq_len < aq->aq_maxlen)) {
106 if (aq->aq_tail == NULL) {
107 aq->aq_head = m;
108 } else {
109 aq->aq_tail->m_nextpkt = m;
110 age -= M_AGE_GET(aq->aq_head);
111 }
112 KASSERT(age >= 0, ("age %d", age));
113 M_AGE_SET(m, age);
114 m->m_nextpkt = NULL;
115 aq->aq_tail = m;
116 aq->aq_len++;
32176cfd
RP
117 return 0;
118 } else {
119 /*
120 * No space, drop and cleanup references.
121 */
122 aq->aq_drops++;
32176cfd
RP
123 /* XXX tail drop? */
124 ageq_mfree(m);
125 return ENOSPC;
126 }
127}
128
129/*
130 * Drain/reclaim all frames from an ageq.
131 */
132void
133ieee80211_ageq_drain(struct ieee80211_ageq *aq)
134{
135 ieee80211_ageq_mfree(ieee80211_ageq_remove(aq, NULL));
136}
137
138/*
139 * Drain/reclaim frames associated with a specific node from an ageq.
140 */
141void
142ieee80211_ageq_drain_node(struct ieee80211_ageq *aq,
143 struct ieee80211_node *ni)
144{
145 ieee80211_ageq_mfree(ieee80211_ageq_remove(aq, ni));
146}
147
148/*
149 * Age frames on the age queue. Ages are stored as time
150 * deltas (in seconds) relative to the head so we can check
151 * and/or adjust only the head of the list. If a frame's age
152 * exceeds the time quanta then remove it. The list of removed
153 * frames is is returned to the caller joined by m_nextpkt.
154 */
155struct mbuf *
156ieee80211_ageq_age(struct ieee80211_ageq *aq, int quanta)
157{
158 struct mbuf *head, **phead;
159 struct mbuf *m;
160
161 phead = &head;
162 if (aq->aq_len != 0) {
32176cfd
RP
163 while ((m = aq->aq_head) != NULL && M_AGE_GET(m) < quanta) {
164 if ((aq->aq_head = m->m_nextpkt) == NULL)
165 aq->aq_tail = NULL;
166 KASSERT(aq->aq_len > 0, ("aq len %d", aq->aq_len));
167 aq->aq_len--;
168 /* add to private list for return */
169 *phead = m;
170 phead = &m->m_nextpkt;
171 }
172 if (m != NULL)
173 M_AGE_SUB(m, quanta);
32176cfd
RP
174 }
175 *phead = NULL;
176 return head;
177}
178
179/*
180 * Remove all frames matching the specified node identifier
181 * (NULL matches all). Frames are returned as a list joined
182 * by m_nextpkt.
183 */
184struct mbuf *
185ieee80211_ageq_remove(struct ieee80211_ageq *aq,
186 struct ieee80211_node *match)
187{
188 struct mbuf *m, **prev, *ohead;
189 struct mbuf *head, **phead;
190
32176cfd
RP
191 ohead = aq->aq_head;
192 prev = &aq->aq_head;
193 phead = &head;
194 while ((m = *prev) != NULL) {
195 if (match != NULL && m->m_pkthdr.rcvif != (void *) match) {
196 prev = &m->m_nextpkt;
197 continue;
198 }
199 /*
200 * Adjust q length.
201 */
202 KASSERT(aq->aq_len > 0, ("aq len %d", aq->aq_len));
203 aq->aq_len--;
204 /*
205 * Remove from forward list; tail pointer is harder.
206 */
207 if (aq->aq_tail == m) {
208 KASSERT(m->m_nextpkt == NULL, ("not last"));
209 if (aq->aq_head == m) { /* list empty */
210 KASSERT(aq->aq_len == 0,
211 ("not empty, len %d", aq->aq_len));
212 aq->aq_tail = NULL;
213 } else { /* must be one before */
214 aq->aq_tail = (struct mbuf *)((uintptr_t)prev -
215 offsetof(struct mbuf, m_nextpkt));
216 }
217 }
218 *prev = m->m_nextpkt;
219
220 /* add to private list for return */
221 *phead = m;
222 phead = &m->m_nextpkt;
223 }
224 if (head == ohead && aq->aq_head != NULL) /* correct age */
225 M_AGE_SET(aq->aq_head, M_AGE_GET(head));
32176cfd
RP
226
227 *phead = NULL;
228 return head;
229}